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Rare Metals 2014年第4期33卷 427-432页

作者： yan-liang Yi Yi-Long liang Qi-Bing Tan The Key Laboratory for Mechanical Behavior and Microstructure of Materials School of Materials and MetallurgyGuizhou University

The effect of rare earth （RE） on bainite trans- formation mechanism is not yet unified in the academia. Therefore, further studying the effect of RE on bainite transformation mechanism will have important guiding significance for the development of bainite steels. In this paper, using differential dilatometer （DIL805A/D）, heat treatment was performed and C-curve was drawn. The effect of phase structure factor on bainite transformation under two different fractions of RE in Si-Mn-Mo bainite steels was investigated by the empirical electron theory （EET） of solids, molecules, dilatometry, and metallogra- phy. Experimental results show that RE makes Fe-C- RE segregation structural unit of Si-Mn-Mo bainite steels increase, i.e., the values of phase structure factor （na, FDC） increase, and delay bainite transformation due to the drag effect resulting from the segregation of RE ferrite island interphase and the retardation of RE to carbon diffusion in Si-Mn-Mo bainite steels. Beside this, C-curve is shifted to right and down, and microstructures of bainite ferrite and substructures are finer.

关键词： Phase structure factor C-curve Substructure Rare earths

Environmental factors influencing the distribution of total and fecal coliform bacteria in six water storage reservoirs in the Pearl River Delta Region,China

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Journal of Environmental Sciences 2010年第5期22卷 663-668页

作者： Huachang Hong Jianwen Qiu yan liang College of Geography and Environmental Sciences Zhejiang Norraal University Jinhua 321004 China Croucher Institute for Environmental Sciences and the Department of Biology Hong Kong Baptist University Kowloon Tong Hong Kong China

The Pearl River Delta （PRD） is one of the most developed and densely populated regions in *** the amount of pathogens in the source of drinking water is important for improving water *** collected water samples from six major water storage reservoirs in the PRD region in both wet and dry seasons in *** showed that external environmental factors,such as precipitation,location,as well as the internal environmental factors,i.e.,physicochemical properties of the water,were closely related with the distribution of ***,the coliform bacterial concentrations in wet season were one to two orders of magnitude greater than those in dry ***,coliform bacterial levels in reservoirs near urban and industrial areas were significantly higher （p 〈 0.05） than those in remote *** analyses showed that the levels of coliforms had close relationships with pH,temperature,suspended solid,organic and inorganic nutrients in *** components analysis further demonstrated that total coliforms in the reservoirs were closely related with water physicochemical properties,while fecal coliforms were more associated with external input brought in by seasonal runoff.

关键词： coliform bacteria location rainfall physicochemical parameters reservoir

Optimal Matching Analysis of Net Buoyancy and Pitching Angle for Underwater Gliders

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China Ocean Engineering 2022年第5期36卷 697-706页

作者： yanG Ming liang yan WANG yan-hui yanG Shao-qiong Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education School of Mechanical EngineeringTianjin UniversityTianjin 300350China The Joint Laboratory of Ocean Observing and Detection Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

Control parameter optimization is an efficient way to improve the endurance of underwater gliders(UGs),which influences their gliding efficiency and energy *** paper analyzes the optimal matching between the net buoyancy and the pitching angle and proposes a segmented control strategy of *** optimization of this strategy is established based on the gliding range model of UG,which is solved based on the approximate model,and the variations of the optimal control parameters with the hotel load are *** optimization results indicate that the segmented control strategy can significantly increase the gliding range when the optimal matching between the net buoyancy and the pitching angle is reached,and the increase rate is influenced by the hotel *** gliding range of the underwater glider can be increased by 10.47%at a hotel load of 0.5 *** optimal matching analysis adopted in this study can be applied to other UGs to realize endurance improvement.

关键词： optimal matching analysis underwater glider approximate model technology gliding range model

Advances in the genetic etiology of premature ovarian insufficiency

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Science China(Life Sciences) 2023年第7期66卷 1705-1707页

作者： Qi Guo Xiao-yan liang Center of Reproductive Medicine The Sixth Affiliated HospitalSun Yat-sen UniversityGuangzhou510080China Guangdong Engineering Technology Research Center of Fertility Preservation Guangzhou510080China

Premature ovarian insufficiency(POI),defined as the loss of ovarian function in women before the age of 40 years,is a challenging reproductive issue that affects hundreds of millions of people globally with compromised fertility and a higher risk of cardiovascular *** is highly heterogeneous in etiology,including genetic,infectious,metabolic,environmental,iatrogenic,and immunological factors.

关键词： insufficiency etiology cardiovascular

Folic acid-induced animal model of kidney disease

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Animal Models and Experimental Medicine 2021年第4期4卷 329-342页

作者： liang-Jun yan Department of Pharmaceutical Sciences College of PharmacyUniversity of North Texas Health Science CenterFort WorthTexasUSA

The kidneys are a vital organ that is vulnerable to both acute kidney injury(AKI)and chronic kidney disease(CKD)which can be caused by numerous risk factors such as ischemia,sepsis,drug toxicity and drug overdose,exposure to heavy metals,and *** spite of the advances in our understanding of the pathogenesis of AKI and CKD as well AKI transition to CKD,there is still no available therapeutics that can be used to combat kidney disease effectively,highlighting an urgent need to further study the pathological mechanisms underlying AKI,CKD,and AKI progression to *** this regard,animal models of kidney disease are *** article reviews a widely used animal model of kidney disease,which is induced by folic acid(FA).While a low dose of FA is nutritionally beneficial,a high dose of FA is very toxic to the *** a brief description of the procedure for disease induction by FA,major mechanisms of FA-induced kidney injury are then reviewed,including oxidative stress,mitochondrial abnormalities such as impaired bioenergetics and mitophagy,ferroptosis,pyroptosis,and increased expression of fibroblast growth factor 23(FGF23).Finally,application of this FA-induced kidney disease model as a platform for testing the efficacy of a variety of therapeutic approaches is also *** that this animal model is simple to create and is reproducible,it should remain useful for both studying the pathological mechanisms of kidney disease and identifying therapeutic targets to fight kidney disease.

关键词： acute kidney injury chronic kidney disease ferroptosis fibroblast growth factor 23 folic acid mitochondria mitophagy oxidative stress pyroptosis

Gain-scheduled L-one control for linear parameter-varying systems with parameter-dependent delays

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控制理论与应用（英文版） 2011年第4期9卷 617-623页

作者： yanhui LI yan liang Electrical and Information Engineering College Northeast Petroleum University Daqing Heilongjiang 163318 China

This paper deals with the problem of gain-scheduled L-one control for linear parameter-varying （LPV） systems with parameter-dependent delays. The attention is focused on the design of a gain-scheduled L-one controller that guarantees being an asymptotically stable closed-loop system and satisfying peak-to-peak performance constraints for LPV systems with respect to all amplitude-bounded input signals. In particular, concentrating on the delay-dependent case, we utilize parameter-dependent Lyapunov functions （PDLF） to establish peak-to-peak performance criteria for the first time where there exists a coupling between a Lyapunov function matrix and system matrices. By introducing a slack matrix, the decoupling for the parameter-dependent time-delay LPV system is realized. In this way, the sufficient conditions for the existence of a gain-scheduled L-one controller are proposed in terms of the Lyapunov stability theory and the linear matrix inequality （LMI） method. Based on approximate basis function and the gridding technique, the corresponding controller design is cast into a feasible solution problem of the finite parameter linear matrix inequalities. A numerical example is given to show the effectiveness of the proposed approach.

关键词： Gain-scheduled L-one control LPV systems Parameter-dependent delays Parameter-dependent Lyapunov functions

Threshold-type memristor-based crossbar array design and its application in handwritten digit recognition

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Journal of Systems Engineering and Electronics 2023年第2期34卷 324-334页

作者： LI Qingjian liang yan LU Zhenzhou WANG Guangyi School of Electronic and Information Hangzhou Dianzi UniversityHangzhou 310018China

Neuromorphic computing simulates the operation of biological brain function for information processing and can potentially solve the bottleneck of the Von Neumann *** by the real characteristics of physical memristive devices,we propose a threshold-type nonlinear voltage-controlled memristor mathematical model which is used to design a novel memristor-based crossbar *** presented crossbar array can simulate the synaptic weight in real number field rather than only positive number *** analysis and simulation results of a 2×2 image inversion operation validate the feasibility of the proposed crossbar array and the necessary training and inference ***,the presented crossbar array is used to construct the neural network and then applied in the handwritten digit *** Mixed National Institute of Standards and Technology(MNIST)database is adopted to train this neural network and it achieves a satisfactory accuracy.

关键词： memristor threshold characteristic modelling electrical synapse crossbar array

Trajectory prediction of ballistic missiles using Gaussian process error model

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Chinese Journal of Aeronautics 2022年第1期35卷 458-469页

作者： Ruiping JI yan liang Linfeng XU Zhenwei WEI School of Automation Northwestern Polytcchnical UniversityXi'an 710129China Key Laboratory of Information Fusion Technology Ministry of EducationXi'an 710129China

Ballistic Missile Trajectory Prediction(BMTP)is critical to air defense *** Trajectory Prediction(TP)methods focus on the coast and reentry phases,in which the Ballistic Missile(BM)trajectories are modeled as ellipses or the state components are propagated by the dynamic integral equations on time *** contrast,the boost-phase TP is more challenging because there are many unknown forces acting on the BM in this *** tackle this difficult problem,a novel BMTP method by using Gaussian Processes(GPs)is proposed in this *** particular,the GP is employed to train the prediction error model of the boost-phase trajectory database,in which the error refers to the difference between the true BM state at the prediction moment and the integral extrapolation of the BM *** the final BMTP is a combination of the dynamic equation based numerical integration and the GP-based prediction *** the trained GP aims to capture the relationship between the numerical integration and the unknown error,the modified BM state prediction is closer to the true one compared with the original ***,the GP is able to output the uncertainty information of the TP,which is of great significance for determining the warning range centered on the predicted BM *** results show that the proposed method effectively improves the BMTP accuracy during the boost phase and provides reliable uncertainty estimation boundaries.

关键词： Ballistic missile Boost-phase trajectory State prediction Gaussian processes Uncertainty estimation

Study on time-varying seismic vulnerability and analysis of ECC-RC composite piers using high strength reinforcement bars in offshore environment

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Earthquake Engineering and Engineering Vibration 2022年第4期21卷 1035-1051页

作者： liang yan Zhao Fulin Luo Jun Chen Pei College of Civil Engineering Zhengzhou UniversityZhengzhou 450001China College of Mechanics and Safety Engineering Zhengzhou UniversityZhengzhou 450001China Wuhan Building Material Industry Design&Research Co. LtdWuhan 430000China

As the main seismic component of a bridge,seismic damage to the bridge pier has a greater effect on its subsequent *** the offshore chloride environment,the issues(e.g.,reinforcement bar corrosion and attenuation of concrete strength)of piers caused by chloride ion seriously curtail the normal service life and deteriorate the anti-seismic property of bridge *** engineered cementitious composite(ECC)-reinforced concrete(RC)composite pier with high strength reinforcement bars(HSRB)is expected to solve the above *** study aims to clarify the time-varying seismic vulnerability(SV)of the HSRBECC-RC composite pier during its full life cycle(FLC).Based on OpenSees,the refined finite element analysis models of RC pier,ECC-RC composite pier,and HSRBECC-RC composite pier have been ***,using the nonlinear time-path dynamic analysis method,the influence of chloride ion erosion on the time-dependent seismic vulnerability(SV)of these different piers in different service life and different peak ground acceleration(PGA)were analyzed from a dynamic point of *** research shows that the exceeding probability(EP)of the same damage level increases with the enhancement of service time and PGA and with the increase of destruction,the exceeding probability(EP)of slight damage(DL-1),moderate damage(DL-2),serious damage(DL-3),and complete collapse(DL-4)decreases in turn;the corrosion degree of chloride ion to piers is small during the early service period,the time-varying vulnerability curve of the bridge piers is almost the same as that of a new bridge,and during later service,as the extent of chloride ion corrosion deepens,exceeding probability(EP)under severe damage(DL-3)and complete collapse(DL-4)is increased,and the seismic performance is significantly enhanced.

关键词： bridge piers engineered cementitious composite(ECC) high strength reinforcement bars(HSRB) seismic vulnerability(SV) exceeding probability(EP) full life cycle(FLC)

Dynamic p-y curves for vertical and batter pile groups in liquefied sand

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Earthquake Engineering and Engineering Vibration 2022年第3期21卷 605-616页

作者： Zhang Jian Li Yurun Rong Xian liang yan School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China Campus Construction and Management Hebei University of TechnologyTianjin 300401China

In this study,centrifuge model tests of vertical and batter pile groups in liquefied sand were conducted on a centrifuge shaking *** dynamic p-y curves for these pile groups before and during sand liquefaction were obtained from calculations based on test *** results confirm that liquefaction contributes to a reduction in the energy consumption of pile foundations,with the degradation effect being more pronounced for batter pile *** shallow depths,the difference in the backbone gradients of the p-y curves after liquefaction for vertical and batter pile groups indicates that the lateral stiffness of a batter pile group is greater than that of a vertical pile *** shaking intensity increases,the lateral stiffness of a vertical pile group increases with depth during the late stage of sand ***,the lateral stiffness of a batter pile group during liquefaction does not vary with *** results of this study provide a reference for the seismic design of vertical and batter pile groups in liquefied soil.

关键词： soil liquefaction pile-soil interaction p-y curve centrifuge shaking table