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Vibration Suppression for Active Magnetic Bearings Using Adaptive Filter with Iterative Search Algorithm

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 61-71页

作者： Jin-Hui Ye Dan Shi Yue-sheng Qi Jin-Hui Gao jian-xin shen IEEE Department of Electrical Engineering Zhejiang UniversityHangzhou 310027China CES and IEEE

Active Magnetic Bearing(AMB) is a kind of electromagnetic support that makes the rotor movement frictionless and can suppress rotor vibration by controlling the magnetic force. The most common approach to restrain the rotor vibration in AMBs is to adopt a notch filter or adaptive filter in the AMB controller. However, these methods cannot obtain the precise amplitude and phase of the compensation current. Thus, they are not so effective in terms of suppressing the vibrations of the fundamental and other harmonic orders over the whole speed range. To improve the vibration suppression performance of AMBs,an adaptive filter based on Least Mean Square(LMS) is applied to extract the vibration signals from the rotor displacement signal. An Iterative Search Algorithm(ISA) is proposed in this paper to obtain the corresponding relationship between the compensation current and vibration signals. The ISA is responsible for searching the compensating amplitude and shifting phase online for the LMS filter, enabling the AMB controller to generate the corresponding compensation force for vibration suppression. The results of ISA are recorded to suppress vibration using the Look-Up Table(LUT) in variable speed range. Comprehensive simulations and experimental validations are carried out in fixed and variable speed range, and the results demonstrate that by employing the ISA, vibrations of the fundamental and other harmonic orders are suppressed effectively.

关键词： Active Magnetic Bearing(AMB) Adaptive filter Iterative search algorithm Least mean square(LMS) Vibration suppression

Torque characteristics in a large permanent magnet synchronous generator with stator radial ventilating air ducts

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Frontiers of Information Technology & Electronic Engineering 2016年第8期17卷 814-824页

作者： He HAO Wei-zhong FEI Dong-min MIAO Meng-jia JIN jian-xin shen College of Electrical Engineering Zhejiang University Hangzhou 310027 China Power Engineering Centre Cranfield University Cranfield MK43 OAL UK

目的:针对应用于海上风电的大型低速直驱型永磁同步发电机,研究具有径向通风风道定子和分段斜极的转子对于电机转矩特性的影响。创新点:利用二维和三维有限元分析,得到定子通风孔的存在对于电机转矩特性的影响,并且通过对永磁体结构和... 详细信息

目的:针对应用于海上风电的大型低速直驱型永磁同步发电机,研究具有径向通风风道定子和分段斜极的转子对于电机转矩特性的影响。创新点:利用二维和三维有限元分析,得到定子通风孔的存在对于电机转矩特性的影响,并且通过对永磁体结构和转子分段斜极的优化,得到其对电机转矩特性的影响,提高电机转矩性能,降低了对机械齿轮的要求。方法:首先,考虑到大型直驱型永磁同步发电机采用的机械齿轮的机械忍耐性受到限制,因此减少电机的转矩脉动具有非常重要的意义,对于海上工作的风力发电机来说尤为如此。接着,针对现有风力发电机,在具有定子通风孔条件下提出了对于电机永磁体形状的优化,并通过二维和三维的有限云分析,得到了其对电机转矩特性的影响。然后,通过提出对电机转子的分段斜极的优化,同样利用二维和三维的有限元分析得到不同转子结构对电机转矩特性的影响。最后,通过分析比较得到不同结构对电机平均转矩、转矩脉动等的影响。结论:针对大容量永磁同步发电机,我们发现定子通风孔不仅会降低电机的平均转矩,还会增加电机的转矩脉动,且电枢电流和转子分段斜极对减少电机的转矩脉动具有非常大的影响。

关键词：永磁同步发电机转矩特性径向通风通风管道定子二维有限元分析三维有限元分析海上风力发电

Square-Wave Drive for Synchronous Reluctance Machine and its Torque Ripple Analysis

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CES Transactions on Electrical Machines and Systems 2021年第4期5卷 273-283页

作者： jian-xin shen Shun Cai Dong-Min Miao Dan Shi Jacek Gieras Yun-Chong Wang the College of Electrical Engineering Zhejiang UniversityZhejiang Provincial Key Laboratory of Electrical Machine SystemsHangzhou310027China the School of Electrical and Electronic Engineering Nanyang Technological University639798Singapore the Department of Electrical Engineering UTP University of Science and TechnologyBydgoszcz85-796Poland

Synchronous reluctance machine(SynRM)can be perceived as a special type of permanent magnet synchronous machine(PMSM),and shares similar control method,i.***.the sine-wave current drive with sinusoidal phase currents.In this paper,square-wave drive,which is employed for permanent magnet brushless(BLDC)motors,is employed for the SynRM,in order to economically reduce the cost of rotor position sensor.It is revealed that the torque density and efficiency are slightly sacrificed,whereas torque ripple is deteriorated,proving the SynRM with square-wave drive still promising for the cost-sensitive application if torque ripple is not considered as a critical issue.To further investigate the additional pulsating torque under square-wave drive,mathematical model based on a-b-c phase inductance and d-q axis inductance are established,together with the time-stepping FE calculated currents.It is concluded that the harmonics in the currents tend to cause non-sinusoidal variation of the magnetic reluctance,which can be represented as additional inductance harmonics.The harmonics of the current and inductance interact with each other,thus undesirable torque ripple components are produced.

关键词： Synchronous reluctance machine pulsating torque square-wave drive inductance magnetic saturation

Incidence,Risk Factors,and Prognosis of Patients with Hepatocellular Carcinoma and Brain Metastases

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Current Medical Science 2024年第1期44卷 180-186页

作者： Jin-cheng FENG Ying HE Georgios Polychronidis jian xin shen YOU Jun XIONG Department of Liver Transplantation Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China Key Laboratory of Transplant Engineering and Immunology Laboratory of Liver TransplantationFrontiers Science Center for Disease-Related Molecular NetworkWest China HospitalSichuan UniversityChengdu 610041China Department of General Visceral and Transplant SurgeryUniversity of HeidelbergIm Neuenheimer Feld 110Heidelberg 69120Germany Department of Hepatobiliary and Pancreatic Surgery Fujian Provincial HospitalFuzhou 350001China

Objective Brain metastases significantly impact the clinical course of patients with hepatocellular carcinoma(HCC).This study aimed to examine the age-related incidence,demographics,and survival of patients with HCC and brain metastases.Methods Data of HCC patients from 2010 to 2015 in the Surveillance,Epidemiology,and End Results(SEER)Registry were screened for the presence of brain metastases.They were stratified by age and ethnicity.Multivariable logistic and Cox regression analyses were used to identify factors associated with brain metastases and those with overall survival(OS)and liver cancer-specific survival(CSS),respectively.Results A total of 141 HCC patients presenting with brain metastases were identified,accounting for 0.35% of all HCC patients and 2.37% of patients with metastatic disease.Among all HCC patients,the incidence rate was the highest among patients aged 30-49 years old(0.47%).Ethnicity was not associated with the presence of brain metastases at the time of HCC diagnosis.However,African-American patients presented with a significantly lower disease-specific survival[median time:1 month;interquartile range(IQR):0-3.0 months].Initial lung or bone metastasis was independently associated with an increased risk of the presence of brain metastases[odds ratio(OR):12.62,95% confidence interval(CI):8.40-18.97]but was not associated with a worse OS or CSS among those with brain metastases.Conclusion This study identified the age-related incidence and risk factors of brain metastases in HCC patients.These results may contribute to the consideration of brain screening among patients with initial metastatic HCC with lung or bone metastases,and influence the counseling of this patient population regarding their prognosis.

关键词： brain metastases hepatocellular carcinoma age-related incidence cancer-specific survival overall survival

NF-κB in biology and targeted therapy:new insights and translational implications

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1322-1358页

作者： Qing Guo Yizi Jin xinyu Chen Xiaomin Ye xin shen Mingxi Lin Cheng Zeng Teng Zhou jian Zhang Department of Medical Oncology Fudan University Shanghai Cancer CenterNo.270Dong'an RoadShanghai 200032China Department of Oncology Shanghai Medical CollegeFudan UniversityShanghaiChina State Key Laboratory of Oncogenes and Related Genes Renj-Med-X Stem Cell Research CenterShanghai Cancer Institute&Department of UrologyRen Ji HospitalSchool of Medicine and School of Biomedical EngineeringShanghai Jiao Tong UniversityShanghai 200127PR China Department of Cardiology the First Affiliated Hospital of Sun Yat-Sen University58 Zhongshan 2nd RoadGuangzhou 510080China Department of Neurology Rujin HospitalShanghai JiaoTong University Schoolof MedicineShanghaiChina

NF-κB signaling has been discovered for nearly 40 years.Initially,NF-κB signaling was identified as a pivotal pathway in mediating inflammatory responses.However,with extensive and in-depth investigations,researchers have discovered that its role can be expanded to a variety of signaling mechanisms,biological processes,human diseases,and treatment options.In this review,we first scrutinize the research process of NF-κB signaling,and summarize the composition,activation,and regulatory mechanism of NF-κB signaling.We investigate the interaction of NF-κB signaling with other important pathways,including PI3K/AKT,MAPK,JAK-STAT,TGF-β,Wnt,Notch,Hedgehog,and TLR signaling.The physiological and pathological states of NF-κB signaling,as well as its intricate involvement in inflammation,immune regulation,and tumor microenvironment,are also explicated.Additionally,we illustrate how NF-κB signaling is involved in a variety of human diseases,including cancers,inflammatory and autoimmune diseases,cardiovascular diseases,metabolic diseases,neurological diseases,and covID-19.Further,we discuss the therapeutic approaches targeting NF-κB signaling,including IKK inhibitors,monoclonal antibodies,proteasome inhibitors,nuclear translocation inhibitors,DNA binding inhibitors,TKls,non-coding RNAs,immunotherapy,and CAR-T.Finally,we provide an outlook for research in the field of NF-κB signaling.We hope to present a stereoscopic,comprehensive NF-κB signaling that will inform future research and clinical practice.

关键词： PI3K/AKT diseases involvement

Preliminary geological interpretation of long-wavelength magnetic anomalies over China and surrounding regions

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Earth and Planetary Physics 2024年第3期8卷 445-458页

作者： Jie Wang YanYan Yang ZhiMa Zeren jian Wang xin Wang Yuxin Luo XuHui shen National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China Key Laboratory of Compound and Chained Natural Hazards Dynamics Ministry of Emergency Management of ChinaBeijing 100085China School of Emergency Management Science and Engineering University of Chinese Academy of SciencesBeijing 100049China National Space Science Center Chinese Academy of SciencesBeijing 100190China

Long-wavelength(>500 km)magnetic anomalies originating in the lithosphere were first found in satellite magnetic surveys.Compared to the striking magnetic anomalies around the world,the long-wavelength magnetic anomalies in China and surrounding regions are relatively weak.Specialized research on each of these anomalies has been quite inadequate;their geological origins remain unclear,in particular their connection to tectonic activity in the Chinese and surrounding regions.We focus on six magnetic high anomalies over the(1)Tarim Basin,(2)Sichuan Basin(3)Great xing’an Range,(4)Barmer Basin,(5)Central Myanmar Basin,and(6)Sunda and Banda Arcs,and a striking magnetic low anomaly along the southern part of the Himalayan-Tibetan Plateau.We have analyzed their geological origins by reviewing related research and by detailed comparison with geological results.The tectonic backgrounds for these anomalies belong to two cases:either ancient basin basement,or subduction-collision zone.However,the geological origins of large-scale regional magnetic anomalies are always subject to dispute,mainly because of limited surface exposure of sources,later tectonic destruction,and superposition of multi-phase events.

关键词： long-wavelength magnetic anomaly lithospheric magnetic anomaly lithospheric magnetic field model satellite magnetic survey CSES

Optimization of tracheoesophageal fistula model established with Tshaped magnet system based on magnetic compression technique

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World Journal of Gastroenterology 2024年第16期30卷 2272-2280页

作者： Miao-Miao Zhang jian-Qi Mao Lin-xin shen Ai-Hua Shi xin Lyu Jia Ma Yi Lyu Xiao-Peng Yan Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Shaanxi Provincial Key Laboratory of Magnetic Medicine The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Zonglian College Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina National Local Joint Engineering Research Center for Precision Surgery&Regenerative Medicine The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Department of Pulmonary and Critical Care Medicine The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710004Shaanxi ProvinceChina Department of Surgical Oncology Shaanxi Provincial People’s HospitalXi’an 710068Shaanxi ProvinceChina

BACKGROUND The magnetic compression technique has been used to establish an animal model of tracheoesophageal fistula(TEF),but the commonly shaped magnets present limitations of poor homogeneity of TEF and poor model control.We designed a Tshaped magnet system to overcome these problems and verified its effectiveness via animal experiments.AIM To investigate the effectiveness of a T-shaped magnet system for establishing a TEF model in beagle dogs.METHODS Twelve beagles were randomly assigned to groups in which magnets of the Tshaped scheme(study group,n=6)or normal magnets(control group,n=6)were implanted into the trachea and esophagus separately under gastroscopy.Operation time,operation success rate,and accidental injury were recorded.After operation,the presence and timing of cough and the time of magnet shedding were observed.Dogs in the control group were euthanized after X-ray and gastroscopy to confirm establishment of TEFs after coughing,and gross specimens of TEFs were obtained.Dogs in the study group were euthanized after X-ray and gastroscopy 2 wk after surgery,and gross specimens were obtained.Fistula size was measured in all animals,and then harvested fistula specimens were examined by hematoxylin and eosin(HE)and Masson trichrome staining.RESULTS The operation success rate was 100%for both groups.Operation time did not differ between the study group(5.25 min±1.29 min)and the control group(4.75 min±1.70 min;P=0.331).No bleeding,perforation,or unplanned magnet attraction occurred in any animal during the operation.In the early postoperative period,all dogs ate freely and were generally in good condition.Dogs in the control group had severe cough after drinking water at 6-9 d after surgery.X-ray indicated that the magnets had entered the stomach,and gastroscopy showed TEF formation.Gross specimens of TEFs from the control group showed the formation of fistulas with a diameter of 4.94 mm±1.29 mm(range,3.52-6.56 mm).HE and Masson trichrome staining showed scar tissue formation and hierarchical structural

关键词： Magnetic surgery Magnetic compression technique Tracheoesophageal fistula Magnet Animal model Beagles

Thermodynamic property of sandwich cylindrical shell structure with metallic wire mesh:Numerical modeling and experimental analysis

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Chinese Journal of Aeronautics 2024年第1期37卷 138-152页

作者： xin XUE Guojian shen Juan LIAO Institute of Metal Rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou 350116China Fujian Shuikou Power Generation Group Co. LTDFuzhou 350000China

As a new addition to lightweight composite structures,the sandwich cylindrical shell with a metallic wire mesh core has emerged as a promising solution for thermodynamic performance analysis at elevated temperatures.The intricate interwoven cellular formations within the metallic wire mesh pose difficulties for thermo-mechanical modeling and property evaluation.First,the constitutive models employed to characterize hysteresis phenomena were presented,comprising isotropic elasticity,Bergstrom-Boyce model,Ogden hyper-elasticity,and parameter identification through mechanical examinations at varying temperatures.Second,the finite element modeling of cylindrical shell structures was determined for modal and steady-state dynamic analyses.Third,the experimental procedures were carried out,including the preparation of the sandwich cylindrical shell and the dynamic testing platform.The first-order natural frequency of the cylindrical shell structure is close to the resonance frequency of the dynamic test results,with a maximum error of 6.5%,demonstrating the accuracy of the simulation model.When compared to the solid-core cylindrical shell,the average insertion loss of the sandwich cylindrical shell structure within the frequency range of 10–1000 Hz at room temperature is up to 11.09 dB.Furthermore,at elevated temperatures,the average insertion loss of the sandwich cylindrical shell decreases but fluctuates as the temperature changes.

关键词： Energy dissipation Metallic matrix composites Numerical analysis Sandwich structure Thermodynamic properties

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-Lin shen jian-Jun He Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early universe.Among these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent reactions.To date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational precision.In this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium abundance.We found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H uncertainty.Currently,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He rate.From the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method