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Dynamic event-triggered finite-time control for multiple Euler-Lagrange systems using integral terminal sliding mode

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Science China(Technological Sciences) 2023年第11期66卷 3164-3173页

作者： wang Yan LI Xiao-meng YUAN wang yao DeYin LI HongYi Information Technology Research Institute Shenzhen Institute of Information TechnologyShenzhen 518172China School of Automation Guangdong University of TechnologyGuangzhou 510006China

The tracking control for multiple Euler-Lagrange systems with external disturbances in finite time under undirected topology is investigated in this paper.A dynamic model is established for the multi-EL systems to accurately describe the general mechanical system.Furthermore,an integral terminal sliding mode surface is devised to converge the tracking errors of the system state to a neighborhood of zero within finite time,and the designed finite-time controller ensures fast convergence and high steady-state accuracy.To reduce the controller update frequency and network transmission communication load,a dynamic event-triggered mechanism is introduced between the sensor and controller,and no Zeno behavior was observed.Therefore,the Lyapunov stability theory and finite-time stability criterion prove that all signals in the closed-loop system are uniformly ultimately bounded in finite time.Finally,the simulation results verified the effectiveness of the proposed control method.

关键词： dynamic event-triggered mechanism external disturbances finite-time control integral terminal sliding mode control multiple Euler–Lagrange systems

Mesothelial cyst of uterine corpus misdiagnosed as leiomyoma

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Chinese Medical Journal 2019年第12期132卷 1502-1503页

作者： Shi-Ping Mo Meng-Yao Wang Jin-Ke Li Department of Obstetrics and Gynecology West China Second HospitalSichuan UniversityChengduSichuan 610041China Key Laboratory of Birth Defects and Related Diseases of Women and Children Ministiy of EducationSichuan UniversityChengduSichuan 610041China

A 46-year old woman (gravida 3, para 1) presented at West China Second Hospital with complaints of a space-occupying lesion in the uterus that, 2 years before, had been diagnosed as a uterine cyst at West China Second Hospital. On that previous occasion, B-ultrasonography revealed a cystic mass with a compartmentalized structure (10.3 × 5.4 × 8.8 cm) on the left side of the pelvic cavity, and laparoscopic exploration found a cystic mass on the posterior uterine wall, which was diagnosed as "leiomyoma with cystic degeneration" based on pathology analysis of flash-frozen surgical tissues. Laparoscopic "myomectomy" was performed, and pathology analysis of paraffin-embedded tissue confirmed "leiomyoma with degeneration." Immunohistochemistry showed the lesion to be positive for caldesmon but negative for CD10. Rate of Ki67 positivity was less than 1%, indicating a benign lesion. The woman recovered well after the operation. Follow-up ultrasonography at 3 months after surgery identified a uterine cystic mass of 3.0 × 2.5 × 1.7 cm.

关键词： Mesothelial cyst uterine corpus as leiomyoma

Changes in equilibrium-line altitude and implications for glacier evolution in the Asian high mountains in the 21st century

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Science China Earth Sciences 2022年第7期65卷 1308-1316页

作者： Keqin DUAN Tandong yao Ninglian wang Peihong SHI Yali meng School of Geography and Tourism Shaanxi Normal UniversityXi'an 710062China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China College of Urban and Environmental Sciences Northwest UniversityXi'an 710127China

In the context of global warming,glaciers in the Asian High Mountains(AHMs)are shrinking at an accelerating rate.Projecting their future change is helpful for understanding the hydrological and climatic effects related to glacier retreat.Here,we projected glacier change in the AHMs from 1979 to 2100 under shared socioeconomic pathway(SSP)scenarios from the perspective of temperature,equilibrium-line altitude(ELA),and accumulation area.The annual mean temperature in the AHMs increased by 1.26℃ from 1979 to 2014,corresponding to an increase of 210 m in the mean ELA and a decrease of 1.7×10^(4)km^(2) in the glacier accumulation area.Under the SSP2-4.5(SSP5-8.5)scenario,the annual mean temperature in the AHMs would increase by 2.84℃(3.38℃)in 2040–2060 relative to that in 1850–1900,leading to the mean ELA reaching an elevation of5661 m(5777 m).The accumulation area in the AHMs decreased by 46.3%from 1995 to 2014 and was projected to decrease by60.1%in 2040–2060.Moreover,the annual mean temperature in the AHMs was projected to increase by 3.76℃(6.44℃)in2080–2100 relative to that in 1850–1900,corresponding to the ELA reaching an elevation of 5821 m(6245 m)and the accumulation area decreasing to 1.8×10^(4)km^(2)(0.5×10^(4)km^(2)).These data suggest that the conditions for glacier development will disappear in most of the AHMs,except for extreme high-altitude regions in the Tianshan,Pamir,and Himalaya Mountains.Under the SSP2-4.5(SSP5-8.5)scenario,when the global mean temperature increases 1.5℃(2℃)above pre-industrial levels,the annual mean temperature will increase by 2.12℃(2.86℃)and the accumulation area will decrease by 15%(48%)in the AHMs compared with that in 1995–2015.Therefore,a 1.5℃ increase in global warming would keep 40%more of the glacial accumulation area(1.5×10^(4)km^(2))in the AHMs compared to a 2℃ increase in global warming.

关键词： Asia High Mountains Glacier Equilibrium-line altitude Accumulation area CMIP6

Effect of roughness on the shear behavior of rock joints subjected to impact loading

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第2期15卷 339-349页

作者： Feili wang Shuhong wang Wei yao Xing Li Fanzheng meng Kaiwen Xia College of Science Qingdao University of TechnologyQingdao266033China School of Resource and Civil Engineering Northeastern UniversityShenyang110819China State Key Laboratory of Hydraulic Engineering Simulation and Safety School of Civil EngineeringTianjin UniversityTianjin300072China Department of Civil and Mineral Engineering University of TorontoTorontoOntarioM5S 1A4Canada

The shear behavior is regarded as the dominant property of rock joints and is dramatically affected by the joint surface roughness.To date,the effect of surface roughness on the shear behavior of rock joints under static or cyclic loading conditions has been extensively studied,but such effect under impact loading conditions keeps unclear.To address this issue,a series of impact shear tests was performed using a novel-designed dynamic experimental system combined with the digital image correlation(DIC)technique.The dynamic shear strength,deformability and failure mode of the jointed specimens with various joint roughness coefficients(JRC)are comprehensively analyzed.Results show that the shear strength and shear displacement characteristics of the rock joint under the impact loading keep consistent with those under static loading conditions.However,the temporal variations of shear stress,slip displacement and normal displacement under the impact loading conditions show obviously different behaviors.An elastic rebound of the slip displacement occurs during the impact shearing and its value increases with increasing joint roughness.Two identifiable stages(i.***.compression and dilation)are observed in the normal displacement curves for the rougher rock joints,whereas the joints with small roughness only manifest normal compression displacement.Besides,as the roughness increases,the maximum compression tends to decrease,while the maximum dilation gradually increases.More-over,the microstructural analysis based on scanning electron microscope(SEM)suggests that the roughness significantly affects the characteristics of the shear fractured zone enclosing the joint surface.

关键词： Rock joint Impact loading Joint roughness Shear strength Shear deformability

Enhancing photocatalytic hydrogen peroxide production of Tibased metal-organic frameworks:The leading role of facet engineering

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Nano Research 2022年第7期15卷 6045-6053页

作者： Xue-Yang Ji yao-yao wang Yun Li Ke Sun meng Yu Jun Tao Key Laboratory of Cluster Science of Ministry of Education School of Chemistry and Chemical EngineeringLiangxiang CampusBeijing Institute of TechnologyBeijing 102488China

Rational construction of the facet engineering over metal-organic frameworks is of significant interest for enhancing photocatalytic performance,yet the role of modulator except regulating facet is largely ignored.Herein,facet engineering of NH_(2)-MIL125(aMIL)was achieved through the facile one-pot method by controlling the concentration of acetic acid modulator.The probable domino effects induced with the detectable modulator were extensively investigated,evidencing the multi-position in one mode contained powder X-Ray diffraction(PXRD),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS),and X-ray absorption spectroscopy(XAS),etc.Meanwhile,correlation among the{111}facets engineering,the degree of structural defects,and the performance of photocatalytic hydrogen peroxide(H_(2)O_(2))production was studied in detail,revealing that facet and defect engineering respectively play positive and relatively negative roles in the photocatalytic oxygen reduction reaction(ORR)with a volcano-type trend.aMIL-3 photocatalyst could deliver H_(2)O_(2) production rate of 925.8μmol·h^(−1)·g^(−1)(2.03-fold of aMIL)under visible-light irradiation and a quantum yield of 1.08%at 420 nm.

关键词： metal-organic frameworks facet engineering defects photocatalyst hydrogen peroxide production

The Health Demands of Designated Drivers-Four Cities,China,2019

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China CDC weekly 2022年第20期4卷 426-430页

作者： meng Zhang Qiqi wang Hongyan yao Xiao Qi Shicheng Yu Jianjun Liu Office of Epidemiology Chinese Center for Disease Control and PreventionBeijingChina Chinese Center for Disease Control and Prevention BeijingChina

Summary What is already known about this topic?The health status of designated drivers is largely associated with road safety,which is a major public health issue.However,few studies have focused on the health demands of designated drivers.What is added by this report?This study investigated the health consciousness,first aid knowledge learning,acceptable ways to acquire health knowledge,and willingness to have physical examinations for designated drivers to provide suggestions for improving their health status.What are the implications for public health practice?The industry and platform should provide scientific and reasonable guidance on healthy lifestyles for designated drivers and implement physical examinations to monitor their health status.

关键词： designated knowledge consciousness

Sparse recovery: from vectors to tensors

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National Science Review 2018年第5期5卷 756-767页

作者： yao wang Deyu meng Ming Yuan School of Mathematics and Statistics Xi'an Jiaotong University Shenyang Institute of Automation Chinese Academy of Sciences Ministry of Education Key Lab of Intelligent Networks and Network Security Xi'an Jiaotong University Department of Statistics Columbia University

Recent advances in various fields such as telecommunications, biomedicine and economics, among others, have created enormous amount of data that are often characterized by their huge size and high dimensionality. It has become evident, from research in the past couple of decades, that sparsity is a flexible and powerful notion when dealing with these data, both from empirical and theoretical viewpoints. In this survey, we review some of the most popular techniques to exploit sparsity, for analyzing high-dimensional vectors, matrices and higher-order tensors.

关键词： high-dimensional data sparsity compressive sensing low-rank matrix recovery tensors

Antibody prevalence and immunotherapy response in Chinese patients with epilepsy and encephalopathy scores for patients with different neuronal surface antibodies

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Chinese Medical Journal 2021年第24期134卷 2985-2991页

作者： Yu Jia Hui-Fang wang meng-yao Zhang Yu-Ping wang Department of Neurology Xuanwu HospitalCapital Medical UniversityBeijing 100053China Beijing Key Laboratory of Neuromodulation Beijing 100053China Center of Epilepsy Beijing Institute for Brain DisordersCapital Medical UniversityBeijing 100053China

Background:The scale assessment was helpful in predicting the presence of antibodies to autoimmune encephalitis.This study aimed to evaluate the application of antibody prevalence in Chinese patients with epilepsy and encephalopathy(APE2-CHN)and response to immunotherapy in Chinese patients with epilepsy and encephalopathy(RITE2-CHN)for patients with different neuronal surface antibodies.Methods:A total of 1365 patients with epileptic seizures as the prominent feature in Xuanwu Hospital,Capital Medical University,from June 2016 to June 2020 were enrolled in our study.Of these,915 patients with epilepsy of unknown etiology whose serum and/or cerebrospinal fluid samples were examined for autoimmune antibodies were selected.All patients were scored with antibody prevalence in patients with epilepsy and encephalopathy(APE2),response to immunotherapy with epilepsy and encephalopathy(RITE2),APE2-CHN,and RITE2-CHN scores.Results:Of the 915 patients,191 patients were positive for neural-surface specific antibodies(115 N-methyl-D-aspartate receptor(NMDAR)Ab,47 leucine-rich glioma-inactivated protein 1(LGI1)Ab,8 contactin-associated protein 2(CASPR2)Ab,4 AMPA2RAb,and 11 GABAR-B-Ab;3 CASPR2-Ab and LGI1-Ab,2 NMDAR-Ab and CASPR2-Ab,and 1 NMDAR-Ab and myelinoligodendrocyte glycoprotein[MOG]Ab).The sensitivity and specificity of APE2≥4 in predicting the presence of neural-surface specific antibodies in our study were 74.35%and 81.77%,respectively,and the sensitivity and specificity of APE2-CHN≥4 were 75.92%and 84.53%,respectively.Eight cases had an APE2 score<4 and APE2-CHN score≥5;all these patients had memory decline as the prominent manifestation.We divided the patients into six groups according to the different antibodies.APE2-CHN scores showed higher sensitivity for the prediction of NMDAR-Ab,but lower sensitivity for LGI1-Ab.A total of 187/191(97.91%)patients received immunotherapy and 142/191(74.35%)patients benefited from the treatments.The patients who were positive for LGI1-Ab with RITE2-CHN≥8 responded well to immuno

关键词： APE2-CHN RITE2-CHN APE2 RITE2 Neuronal surface antibody Immunotherapy

Physicochemical and Morphological Variation of Bamboo Cell Wall During Hydrothermal Pretreatment

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Paper And Biomaterials 2022年第1期7卷 1-8页

作者： Xiaojuan Yu Kai Fan Xi yao meng wang Kun wang MOE Engineering Research Center of Forestry Biomass Materials and Bioenergy College of Materials Science and TechnologyBeijing Forestry UniversityBeijing100083China International Centre for Bamboo and Rattan Beijing100102China China National Pulp and Paper Research Institute Co. Ltd.Beijing100102China

Pretreatment is important for achieving high-value utilization of biomass.This study is conducted to evaluate the destruction of the Moso bamboo cell wall via hydrothermal pretreatment at different temperatures and pH values.Compositional and morphological analyses and subsequent enzymatic hydrolysis of the solid fractions indicate that the destruction of the cell wall,instead of the degradation or removal of hemicellulose and lignin,or the configuration transition of the cellulose crystal structure,is the most critical aspect for improving bioconversion efficiency.Although only an 8%-10%weight loss is incurred and similar crystalline indexes are achieved after mild hydrothermal treatments,the recovery of glucose is doubled,whereas the recovery of xylose from pretreated samples is approximately 35%.

关键词： bamboo morphological variation pretreatment enzymatic hydrolysis