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An Adaptive Single Neural Control for Variable Step-Size P&O MPPT of Marine Current Turbine System

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China Ocean Engineering 2021年第5期35卷 750-758页

作者： LI Ming-zhu WANG Tian-zhen zhou fu-na SHI Ming Logistics Engineering College Shanghai Maritime UniversityShanghai 201306China Shanghai Investigation Design and Research Institute Co.LtdShanghai 200434China

Marine current energy has been increasingly used because of its predictable higher power potential.Owing to the external disturbances of various flow velocity and the high nonlinear effects on the marine current turbine(MCT)system,the nonlinear controllers which rely on precise mathematical models show poor performance under a high level of parameters’uncertainties.This paper proposes an adaptive single neural control(ASNC)strategy for variable step-size perturb and observe(P&O)maximum power point tracking(MPPT)control.Firstly,to automatically update the neuron weights of SNC for the nonlinear systems,an adaptive mechanism is proposed to adaptively adjust the weighting and learning coefficients.Secondly,aiming to generate the exact reference speed for ASNC to extract the maximum power,a variable step-size law based on speed increment is designed to strike a balance between tracking speed and accuracy of P&O MPPT.The robust stability of the MCT control system is guaranteed by the Lyapunov theorem.Comparative simulation results show that this strategy has favorable adaptive performance under variable velocity conditions,and the MCT system operates at maximum power point steadily.

关键词： marine current turbine system perturb and observe single neural control adaptive mechanism maximum power point tracking

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数据驱动的电气工程因材施教育人模式研究

教育教学论坛 2024年第7期 145-148页

作者：张琴周福娜向阳上海海事大学物流工程学院上海201306

大数据正在成为推动教学创新的关键力量,提出数据驱动的电气工程因材施教育人模式。首先以终为始制定新工科下创新型电气工程师的培养目标;课前采用Kolb学习风格量表建立学生的学习风格模型,开展五阶段混合式教学和分组分层教学,促进学... 详细信息

大数据正在成为推动教学创新的关键力量,提出数据驱动的电气工程因材施教育人模式。首先以终为始制定新工科下创新型电气工程师的培养目标;课前采用Kolb学习风格量表建立学生的学习风格模型,开展五阶段混合式教学和分组分层教学,促进学生全员进步;采用基于关系的迁移学习智能算法,将大数据挖掘的优势领域中的逻辑知识和能力关系迁移到薄弱领域,教师给予个性化指导,最终实现以数据驱动的大规模因材施教。

关键词：数据驱动华盛顿协议因材施教 Kolb学习风格迁移学习

Small Cycles Property of Some Cremer Rational Maps and Polynomials

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Chinese Annals of Mathematics,Series B 2024年第1期45卷 123-136页

作者： Rong fu Ji zhou Faculty of Science Yibin UniversityYibin 644000SichuanChina Department of Mathematical Sciences Sichuan Normal UniversityChengdu 610066China

This paper concerns the linearization problem on rational maps of degree d≥2 and polynomials of degree d>2 from the perspective of non-linearizability.The authors introduce a set l_(∞) of irrational numbers and show that if α∈l_(∞),then any rational map is not linearizable and has infinitely many cycles in every neighborhood of the fixed point with multiplier λ=e^(2πiα),Adding more constraints to cubic polynomials,they discuss the above problems by polynomial-like maps.For the family of polynomials,with the help of Yoccoz's method,they obtain its maximum dimension of the set in which the polynomials are non-linearizable.

关键词： Irrationally indifferent fixed point Linearization problem Small cycles property

Iridoids modulate inflammation in diabetic kidney disease: A review

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Journal of Integrative Medicine 2024年第3期22卷 210-222页

作者： Tong-yi zhou na Tian Liu Li Rong Yu The First Clinical College of Chinese Medicine Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina Hunan Provincial Key Laboratory of Translational Research in Traditional Chinese Medicine Prescriptions and Zheng Changsha 410208Hunan ProvinceChina

In recent years,preclinical research on diabetic kidney disease (DKD) has surged to the forefront of scientific and clinical attention.DKD has become a pervasive complication of type 2 diabetes.Given the complexity of its etiology and pathological mechanisms,current interventions,including drugs,dietary modifications,exercise,hypoglycemic treatments and lipid-lowering methods,often fall short in achieving desired therapeutic outcomes.Iridoids,primarily derived from the potent components of traditional herbs,have been the subject of long-standing research.Preclinical data suggest that iridoids possess notable renal protective properties;however,there has been no summary of the research on their efficacy in the management and treatment of DKD.This article consolidates findings from in vivo and in vitro research on iridoids in the context of DKD and highlights their shared anti-inflammatory activities in treating this condition.Additionally,it explores how certain iridoid components modify their chemical structures through the regulation of intestinal flora,potentially bolstering their therapeutic effects.This review provides a focused examination of the mechanisms through which iridoids may prevent or treat DKD,offering valuable insights for future research endeavors.

关键词： Diabetic kidney disease Iridoids Gut-kidney axis Traditional Chinese medicine monomer Inflammation

Accurate atomic scanning transmission electron microscopy analysis enabled by deep learning

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nano Research 2024年第4期17卷 2971-2980页

作者： Tianshu Chu Lei zhou Bowei Zhang fu-Zhen Xuan Shanghai Key Laboratory of Intelligent Sensing and Detection Technology East China University of Science and TechnologyShanghai 200237China School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Pressure Systems and Safety of Ministry of Education East China University of Science and TechnologyShanghai 200237China

Currently,the machine learning(ML)-based scanning transmission electron microscopy(STEM)analysis is limited in the simulative stage,its application in experimental STEM is needed but challenging.Herein,we built up a universal model to analyze the vacancy defects and single atoms accurately and rapidly in experimental STEM images using a full convolution network.In our model,the unavoidable interference factors of noise,aberration,and carbon contamination were fully considered during the training,which were difficult to be considered in the past.Even toward the simultaneous identification of various vacancy types and low-contrast single atoms in the low-quality STEM images,our model showed rapid process speed(45 images per second)and high accuracy(>95%).This work represents an improvement in experimental STEM image analysis by ML.

关键词： deep learning low-dimensional materials atomic defects single atoms

Data-driven rational design of single-atom materials for hydrogen evolution and sensing

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nano Research 2024年第4期17卷 3352-3358页

作者： Lei zhou Pengfei Tian Bowei Zhang fu-Zhen Xuan Shanghai Key Laboratory of Intelligent Sensing and Detection Technology East China University of Science and TechnologyShanghai 200237China School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Pressure Systems and Safety of Ministry of Education East China University of Science and TechnologyShanghai 200237China

Herein we proposed a data-driven high-throughput principle to screen high-performance single-atom materials for hydrogen evolution reaction(HER)and hydrogen sensing by combing the theoretical computations and a topology-based multi-scale convolution kernel machine learning algorithm.After the rational training by 25 groups of data and prediction of all 168 groups of single-atom materials for HER and sensing,respectively,a high prediction accuracy(>0.931 R^(2) score)was achieved by our model.Results show that the promising HER catalysts include Pt atoms in C_(4) and Sc atoms in C_(1)N_(3) coordination environment.Moreover,Y atoms in C_(4) coordination environment and Cd atoms in C_(2)N_(2)-ortho coordination environment were predicted with great potential as hydrogen sensing materials.This method provides a way to accelerate the discovery of innovative materials by avoiding the time-consuming empirical principles in experiments.

关键词： machine learning single-atom materials sensing hydrogen evolution

Incidence and risk factors of depression in patients with metabolic syndrome

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World Journal of Psychiatry 2024年第2期14卷 245-254页

作者： Li-na zhou Xian-Cang Ma Wei Wang Department of Psychiatry The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina

BACKGROUND Many studies have explored the relationship between depression and metabolic syndrome(MetS),especially in older people.China has entered an aging society.However,there are still few studies on the elderly in Chinese communities.AIM To investigate the incidence and risk factors of depression in MetS patients in China's Mainland and to construct a predictive model.METHODS Data from four waves of the China Health and Retirement Longitudinal Study were selected,and middle-aged and elderly patients with MetS(n=2533)were included based on the first wave.According to the center for epidemiological survey-depression scale(CESD),participants with MetS were divided into depression(n=938)and non-depression groups(n=1595),and factors related to depression were screened out.Subsequently,the 2-,4-,and 7-year follow-up data were analyzed,and a prediction model for depression in MetS patients was constructed.RESULTS The prevalence of depression in middle-aged and elderly patients with MetS was 37.02%.The prevalence of depression at the 2-,4-,and 7-year follow-up was 29.55%,34.53%,and 38.15%,respectively.The prediction model,constructed using baseline CESD and Physical Self-Maintenance Scale scores,average sleep duration,number of chronic diseases,age,and weight had a good predictive effect on the risk of depression in MetS patients at the 2-year follow-up(area under the curve=0.775,95%confidence interval:0.750-0.800,P<0.001),with a sensitivity of 68%and a specificity of 74%.CONCLUSION The prevalence of depression in middle-aged and elderly patients with MetS has increased over time.The early identification of and intervention for depressive symptoms requires greater attention in MetS patients.

关键词： Depression Metabolic syndrome Prevalence Risk factor

Macro-microscopic dynamic characteristics of the ballast bed induced by the variation of moisture content

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Particuology 2024年第7期90卷 118-127页

作者： Shuchen Wang Longlong fu Yongjia Qiu Haonan Xi Shunhua zhou Key Laboratory of Road and Traffic Engineering of the Ministry of Education Tongji UniversityShanghai 201804China Shanghai Key Laboratory of Rail Infrastructure Durability and System Safety Tongji UniversityShanghai 201804China

Due to the excellent drainage performance of the ballast,existing studies mainly focus on the dynamic response of ballast under field capacity or saturation.Attention has rarely been paid to dynamic changes in moisture content and potential influences.In this article,we firstly conduct a model test to determine the variation of ballast moisture content under artificial rainfall.After that,a full-scale model test with cyclic loading is carried out to study the effect of moisture content variation on the macro-microscopic response of the ballast bed,where several wireless particle sensors are installed to obtain ballast motion characteristics at strategic locations.The results show that the moisture content increases gradually and stabilizes at a flat peak under rainfall,despite the excellent drainage performance of ballast bed.After halting rainfall,the moisture content drops back to field capacity,which indicates dynamic flowing surface water on ballast particles under rainfall.Such flowing surface water brings changes to the original dynamic equilibrium of ballast bed:macroscopically,the deformation rate of stabilized ballast bed increases significantly,reaching a local peak under field capacity;microscopically,the x-and z-angular accelerations of the ballast show positive correlation with rainfall intensity.The multiscale responses indicate that field capacity is a critical moisture content.

关键词： Railway ballast Flowing surface water Wireless particle sensor Multidimensional motion full-scale model test

Microwave irradiation-induced alterations in physicochemical properties and methane adsorption capability of coals:An experimental study using carbon molecular sieve

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Chinese Journal of Chemical Engineering 2024年第4期68卷 165-180页

作者： Xuexiang fu Xing Tang Yi Xu Xintao zhou Dengfeng Zhang Faculty of Chemical Engineering Kunming University of Science and TechnologyKunming 650500China

In order to comprehend the applicability of microwave irradiation for recovering coalbed methane,it is necessary to evaluate the microwave irradiation-induced alterations in coals with varying levels of metamorphism.In this work,the carbon molecular sieve combined with KMnO_(4)oxidation was selected to fabricate carbon molecular sieve with diverse oxidation degrees,which can serve as model substances toward coals.Afterwards,the microwave irradiation dependences of pores,functional groups,and highpressure methane adsorption characteristics of model substances were studied.The results indicated that microwave irradiation causes rearrangement of oxygen-containing functional groups,which could block the micropores with a size of 0.40-0.60 nm in carbon molecular sieve;meanwhile,naphthalene and phenanthrene generated by macro-molecular structure pyrolysis due to microwave irradiation could block the micropores with a size of 0.70-0.90 nm.These alterations in micropore structure weaken the saturated methane adsorption capacity of oxidized carbon molecular sieve by 2.91%-23.28%,suggesting that microwave irradiation could promote methane desorption.Moreover,the increased mesopores found for oxidized carbon molecular sieve after microwave irradiation could benefit CH4 diffusion.In summary,the oxidized carbon molecular sieve can act as model substances toward coals with different ranks.Additionally,microwave irradiation is a promising technology to enhance coalbed methane recovery.

关键词： Microwave irradiation Physicochemical property Coal matrix Adsorption Carbon molecular sieve

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