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An Overview of Finite/Fixed-Time Control and Its Application in Engineering Systems

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IEEE/CAA Journal of Automatica Sinica 2022年第12期9卷 2106-2120页

作者： Yang liu Hongyi li Zongyu zuo Xiaodi li Renquan Lu IEEE College of Automation and Electronics Engineering Qingdao University of Science and TechnologyQingdao 266061 School of Automation Guangdong University of TechnologyGuangzhou 510006China School of Automation Guangdong University of Technologyand also with the Guangdong Province Key Laboratory of Intelligent Decision and Cooperative ControlGuangzhou 510006China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100083China School of Mathematics and Statistics Shandong Normal UniversityBeijing 100083China Center for Control and Engineering Computation Shandong Normal UniversityJinan 250014China

The finite/fixed-time stabilization and tracking control is currently a hot field in various systems since the faster convergence can be obtained. By contrast to the asymptotic stability,the finite-time stability possesses the better control performance and disturbance rejection property. Different from the finite-time stability, the fixed-time stability has a faster convergence speed and the upper bound of the settling time can be estimated. Moreover, the convergent time does not rely on the initial *** work aims at presenting an overview of the finite/fixed-time stabilization and tracking control and its applications in engineering systems. Firstly, several fundamental definitions on the finite/fixed-time stability are recalled. Then, the research results on the finite/fixed-time stabilization and tracking control are reviewed in detail and categorized via diverse input signal structures and engineering applications. Finally, some challenging problems needed to be solved are presented.

关键词： Adding a power integrator finite/fixed-time control and application homogeneous theory sliding mode control

Effects of Hydrogen Storage System and Renewable Energy Sources for Optimal Bidding Strategy in Electricity Market

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Energy Engineering 2022年第5期119卷 1879-1903页

作者： Can li Xiaode zuo School of Management Jinan UniversityGuangzhou510632China

This work suggested a novel model for obtaining optimum bidding/offering strategy to improve the benefits in case of big *** this regard,several electrical energy resources including:micro turbines,green power sources(wind turbine and photovoltaic system),power storage unit such as Hydrogen storage system with fuel cell,as well as mutual treaties are taken into account in offered *** various models for uncertain parameters based on their natures such as power demand,electricity market tariffs,solar irradiation,temperature and wind speed is one of the contributions of the proposed *** of power demand is modeled by robust optimal method whereas remain uncertain parameters are incorporated in model by stochastic *** of wind speed cased is made by Weibull ***,normal distribution is utilized for production of cases for electricity market tariffs,solar irradiation and *** order to reduce the bidding error loss,the storage devices are corporate with green energy in power unbalanced ***-integer linear programming method is applied for handling of pricing method profiles that have strength against considered uncertainties on power demand of big *** obtained results confirm,the entire electrical energy supplement expenditure of big user in absence of demand uncertainty is$39.63 whereas it is augmented up to$49.47 to achieve robustness *** ***,using of hydrogen storage system by considering the reliability index is reduced the bidding price of the system.

关键词： Bidding uncertain constrains bilateral contracts renewable energy reliability

Spur Gear Tooth Pitting Propagation Assessment Using Model-based Analysis

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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1369-1382页

作者： Xi-Hui liang Zhi-liang liu Jun Pan Ming jian zuo Department of Mechanical Engineering University of Alberta School of Mechatronics Engineering University of Electronic Science and Technology Key Laboratory of Reliability Technology for Mechanical and Electrical Product of Zhejiang Province Zhejiang Sci-Tech University

Tooth pitting is a common failure mode of a gearbox. Many researchers investigated dynamic properties of a gearbox with localized pitting damage on a single gear tooth. The dynamic properties of a gearbox with pitting distributed over multiple teeth have rarely been investi- gated. In this paper, gear tooth pitting propagation to neighboring teeth is modeled and investigated for a pair of spur gears. Tooth pitting propagation effect on time-vary- ing mesh stiffness, gearbox dynamics and vibration char- acteristics is studied and then fault symptoms are revealed. In addition, the influence of gear mesh damping and environmental noise on gearbox vibration properties is investigated. In the end, 114 statistical features are tested to estimate tooth pitting growth. Statistical features that are insensitive to gear mesh damping and environmental noise are recommended.

关键词： Mesh stiffness Mesh damping Geardynamics Vibration Statistical feature Dynamicsimulation

Digital Twins for Engineering Asset Management:Synthesis,Analytical Framework,and Future Directions

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Engineering 2024年第10期41卷 261-275页

作者： Yongkui li Qinyue Wang Xiyu Pan jian zuo Jinying Xu Yilong Han School of Economics and Management Tongji UniversityShanghai 200092China School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA 30332USA School of Architecture and Civil Engineering The University of AdelaideAdelaideSA 5005Australia Department of Engineering University of CambridgeCambridge CB30FAUK

Effective engineering asset management(EAM)is critical to economic development and improving livability in society,but its complexity often impedes optimal asset *** twins(DTs)could revolutionize the EAM paradigm by bidirectionally linking the physical and digital worlds in real *** is great industrial and academic interest in DTs for ***,previous review studies have predominately focused on technical aspects using limited life-cycle perspectives,failing to holistically synthesize DTs for EAM from the managerial point of *** on a systematic literature review,we introduce an analytical framework for describing DTs for EAM,which encompasses three levels:DT 1.0 for technical EAM,DT 2.0 for technical-human EAM,and DT 3.0 for technical-environmental *** this framework,we identify what is known,what is unknown,and future directions at each *** 1.0 addresses issues of asset quality,progress,and cost management,generating technical *** lacks multi-objective self-adaptive EAM,however,and suffers from high application *** is imperative to enable closed-loop EAM in order to provide various functional services with affordable DT *** 2.0 accommodates issues of human-machine symbiosis,safety,and flexibility management,generating managerial value beyond the technical performance improvement of engineering ***,DT 2.0 currently lacks the automation and security of human-machine interactions and the managerial value related to humans is not prominent *** research needs to align technical and managerial value with highly automated and secure DT *** 3.0 covers issues of participatory governance,organization management,sustainable development,and resilience enhancement,generating macro social *** it suffers from organizational fragmentation and can only address limited social governance *** research opportunities exist to coordinate different ***,future research

关键词： Engineering asset management Digital twin Socio-technical theory Structureprocessoutcome literature review

Safety modeling and protection for lithium-ion batteries based on artificial neural networks method under mechanical abuse

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Science China(Technological Sciences) 2021年第11期64卷 2373-2388页

作者： li YiDing WANG WenWei liN Cheng zuo FengHao National Engineering Laboratory for Electric Vehicles Beijing Institute of TechnologyBeijing 100081China Shenzhen Automotive Research Institute Beijing Institute of TechnologyShenzhen 518118China

The safety of lithium-ion batteries under mechanical abuse has become one of the major obstacles affecting the development of electric vehicles. In this paper, the lithium-ion battery safety model under mechanical abuse conditions is proposed by the Back Propagation Artificial Neural Network(BP-ANN) optimized by the Genetic Algorithm(GA). By experimental and simulation results, the proposed method can effectively predict battery mechanical properties. The corresponding correlation coefficient is greater than 0.99, the failure warning model has more safety margin, and the average security margin is greater than 29%. The multi-source warning weight shows that the mechanical soft short-circuit has the greatest warning margin, followed by that of the soft short-circuit of the electrical signal. The thermal soft short-circuit has the lowest warning margin because of the low thermal conductivity. The qualitative simulation results of the battery module reveal that, when electric vehicles are subjected to mechanical abuse conditions, the rapid reduction in the state-of-charge(SOC) of the rear batteries can effectively increase the reliability of the battery module. The proposed safety model is important to protect the safety and stability of lithium-ion batteries, which is conducive to promoting new energy vehicles and protecting the environment.

关键词： lithium-ion battery GA-BP model failure warning warning weight failure protection

Insulin-induced severe thyrotoxic periodic paralysis:A case report

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World Journal of Clinical Cases 2025年第7期13卷 46-51页

作者： Yan-li Wang jian li Department of Endocrinology and Metabolism Zigong First People's HospitalZigong 643000Sichuan ProvinceChina

BACKGROUND Thyrotoxic periodic paralysis(TPP)is an endocrine emergency caused by thyrotoxicosis,manifesting mainly as periodic myasthenia and hypokalemia,and posing a serious threat to the patient's ***,strenuous exercise,alcohol abuse,high carbohydrate intake and insulin injections are common triggers of *** article reports a case of severe TPP induced by insulin injection,elucidates the characteristics and pathogenesis of the disease,analyses the risk factors for triggering TPP,and hopefully provides more clinical data for TPP *** SUMMARY A 38-year-old Asian man presented to the emergency department with a oneweek history of limb weakness and worsening *** medical history included poorly controlled type 2 diabetes and he had been switched to Aspart50 a week *** was alert and oriented with upper extremity strength grade 3 and lower extremity strength grade *** department tests showed hypokalemia of 1.6 mmol/*** paramedics administered 1.5 g of potassium intravenously,followed by 4.0 g *** in the arms and legs *** was referred to endocrinology where he was diagnosed with Graves'disease,with suboptimal control and insulin injections possibly causing *** stopped his insulin and he was discharged with a potassium level of 4.0 mmol/*** Insulin is a trigger for TPP and should be avoided in patients with *** recognition and treatment of TPP is crucial,especially in patients presenting with hypokalemic periodic paralysis.

关键词： Thyrotoxic periodic paralysis Potassium metabolism disorders Insulin Triggers of paralysis Case report

Fracture Network Volume Fracturing Technology in High-temperature Hard Formation of Hot Dry Rock

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Acta Geologica Sinica(English Edition) 2021年第6期95卷 1828-1834页

作者： CHEN zuo XU Guoqing ZHOU jian liU jiankun SINOPEC Research Institute of Petroleum Engineering Beijing 102206China

It is more difficult for a hot dry rock to form a fracture network system than shale due to its special lithology, physical and mechanical properties under high temperature. The essential characteristics, rock mechanics and in-situ stress characteristics of a hot rock mass have been systematically studied by means of laboratory tests and true tri-axial physical simulation. The fracture initiation and propagation characteristics under different geological and engineering conditions are physically simulated, and the main controlling factors for the formation of a complex fracture network are revealed. The technology of low displacement for enhancing thermal cracking, gel fluid for expanding fracture and variable displacement cyclic injection for increasing a fracture network has been applied in the field, and good results have been achieved. Microseismic monitoring results demonstrate that complex fractures were formed in the field test, and the stimulation volume for heat exchanging reaches more than 3 million cubic meters. The research results play an important role in the stimulation technology of an enhanced geothermal system(EGS) and realize a breakthrough for power generation.

关键词： hot dry rock granite fracture network natural fractures thermal cracking cyclic injection volume stimulation Gonghe Basin

Molecular dissection of complex agronomic traits of rice:a team effort by Chinese scientists in recent years

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National Science Review 2014年第2期1卷 253-276页

作者： jianru zuo Jiayang li State Key Laboratory of Plant Genomics and National Plant Gene Research Center Institute of Genetics and Developmental Biology Chinese Academy of Sciences

Rice is a staple food for more than half of the worldwide population and is also a model species for biological studies on monocotyledons. hrough a team efort, Chinese scientists have made rapid and important progresses in rice biology in recent years. Here, we briely review these advances, emphasizing on the regulatory mechanisms of the complex agronomic traits that afect rice yield and grain quality. Progresses in rice genome biology and genome evolution have also been summarized.

关键词： complex agronomic traits shoot architecture reproductive development panicle and grain domestication rice

Optical sampling system using periodically-poled lithium niobate waveguide and nonlinear polarization rotation mode-locked fiber laser

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Frontiers of Optoelectronics 2012年第2期5卷 208-213页

作者： jian li Aiying YANG lin zuo Junsen LAI Yunan SUN School of Optoelectronics Beijing Institute of TechnologyBeijing 100081China

A novel design of optical sampling system has been developed by using sum-frequency generation （SFG） in a periodically-poled lithium niobate （PPLN） waveguide and using passive mode-locked fiber laser pulses as optical sampling pulses. The system achieved high temporal resolution and high sensitivity using a 30 mm length PPLN with quasi phase match period of 19.3 μm and 151 fs sampling pulses which were generated by passive modelock fiber laser based on nonlinear polarization rotation （NPR）. Clear eye-diagram of 10 Gbit/s non-return-to-zeros （NRZ） pseudorandom binary sequence （PRBS） optical signal were successfully reconstructed by this system.

关键词： periodically-poled lithium niobate (PPLN),optical sampling nonlinear polarization rotation (NPR)fiber laser sum-fi'equency generation (SFG)