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Prescribed-time leader-following consensus of linear multi-agent systems by bounded linear time-varying protocols

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Science China(Information Sciences) 2024年第1期67卷 140-153页

作者： Kai ZHANG bin zhou Xuefei YANG Guangren DUAN Center for Control Theory and Guidance Technology Harbin Institute of Technology

This paper considers the prescribed-time leader-following consensus problem of input-constrained linear multi-agent systems under generally directed communication topology in two cases:the Laplacian matrix related to the entire communication topology between agents is either known or *** particular,the consensus problem for the former case is solved by a novel bounded linear time-varying(LTV) protocol,where the feedback gain is formulated by the parametric Lyapunov equation and the knowledge of the Laplacian ***,by utilizing a distributed observer,a fully bounded LTV protocol is proposed for the latter *** should be noted that,compared with the existing results,the system under consideration is more general,the designed protocols are linear,and the consensus problem is accomplished even in a fully distributed ***,the effectiveness of the proposed approach is verified by a numerical example.

关键词： leader-following consensus time-vary feedback prescribed-time control fully distributed consensus

Prescribed time control based on the periodic delayed sliding mode surface without singularities

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Science China(Information Sciences) 2024年第7期67卷 256-270页

作者： bin zhou Yi DING Kang-Kang ZHANG Guang-Ren DUAN Center for Control Theory and Guidance Technology Harbin Institute of Technology

In this paper, nonsingular prescribed-time control is studied based on periodic delayed sliding mode surfaces. Different from the existing sliding mode control, where either singularity problems may appear or the convergence time depends on the initial state, the proposed sliding mode control approaches can achieve prescribed-time convergence without singularity. The proposed nonsingular sliding mode control approaches can be applied to both second-order and high-order nonlinear systems with prescribed-time convergence. As applications of the proposed sliding mode control approaches, the control of hypersonic vehicle systems is revisited. Numerical simulations on the nonlinear model of the hypersonic vehicle system show the effectiveness of the proposed methods.

关键词： prescribed-time control smooth periodic delayed feedback sliding mode control high-order nonlinear systems hypersonic vehicle systems

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SDH-FCOS:An Efficient Neural Network for Defect Detection in Urban Underground Pipelines

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Computers, Materials & Continua 2024年第1期78卷 633-652页

作者： bin zhou Bo Li Wenfei Lan Congwen Tian Wei Yao College of Computer Science South-Central Minzu UniversityWuhan430074China

Urban underground pipelines are an important infrastructure in cities,and timely investigation of problems in underground pipelines can help ensure the normal operation of *** to the growing demand for defect detection in urban underground pipelines,this study developed an improved defect detection method for urban underground pipelines based on fully convolutional one-stage object detector(FCOS),called spatial pyramid pooling-fast(SPPF)feature fusion and dual detection heads based on FCOS(SDH-FCOS)*** study improved the feature fusion component of the model network based on FCOS,introduced an SPPF network structure behind the last output feature layer of the backbone network,fused the local and global features,added a top-down path to accelerate the circulation of shallowinformation,and enriched the semantic information acquired by shallow *** ability of the model to detect objects with multiple morphologies was strengthened by introducing dual detection *** experimental results using an open dataset of underground pipes show that the proposed SDH-FCOS model can recognize underground pipe defects more accurately;the average accuracy was improved by 2.7% compared with the original FCOS model,reducing the leakage rate to a large extent and achieving real-time ***,our model achieved a good trade-off between accuracy and speed compared with other mainstream *** proved the effectiveness of the proposed model.

关键词： Urban underground pipelines defect detection SDH-FCOS feature fusion SPPF dual detection heads

Structural parameter optimization of a furrow opener based on EDEM software

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INTERNATIONAL JOURNAL OF AGRICULTURAL AND BIOLOGICAL ENGINEERING 2024年第3期17卷 115-120页

作者： Wang, Longjie zhou, bin Wan, Chang zhou, Ling Tarim Univ Coll Mech & Elect Engn Alar 843300 Xinjiang Peoples R China Modern Agr Engn Key Lab Univ Educ Dept Xinjiang Uy Alar 843300 Xinjiang Peoples R China Xinjiang Prod & Construct Corps XPCC Key Lab Utili Alar 843300 Xinjiang Peoples R China

To reduce the ditching resistance of a furrow opener during operation, single-factor and multiple-factor combinations were used to explore the influence of the furrow opener's advance speed, blade opening angle, and width on the ditching resistance based on the discrete element method (DEM). A DEM simulation of the furrow opener was developed. Upon changing these influencing factors, the parameters with the least resistance to operation were identified. Furrow openers were fabricated according to the optimized results, and soil trench tests were carried out. Simulations and soil groove tests showed that the minimum ditching resistance was 58.54 N when the current advance speed was 4.47 m/s, the blade opening angle was 32.02 degrees, and the furrow opener width was 51.45 mm. The error between the simulated value of the ditching resistance and the soil trench test was within 10%, and the trends of resistance change were essentially the same, indicating that it is feasible to optimize the structural parameters of a trench furrow opener using DEM. These research results can provide a reference for the parameter optimization of furrow openers.

关键词： furrow opener discrete element optimization ditching resistance SOIL-TOOL INTERACTION PERFORMANCE DEVICE DESIGN

Process-driven susceptibility assessment of glacial lake outburst debris flow in the Himalayas under climate change

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Advances in Climate Change Research 2024年第3期15卷 500-514页

作者： bin zhou Qiang ZOU Hu JIANG Tao YANG Wen-Tao zhou Si-Yu CHEN Hong-Kun YAO Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China School of Environment and Resource Southwest University of Science and TechnologyMianyang 621010China

Global warming is causing glaciers to retreat and glacial lakes to expand in the Himalayas,which amplifies the risk of glacial lake outburst debris flows(GLODFs)and poses a significant threat to downstream lives and ***,the complex interplay between GLODF occurrences and associated indicators,coupled with the lack of a comprehensive susceptibility indicator system that considers the entire GLODF process,presents a substantial challenge in assessing GLODF susceptibility in the *** study proposes a process-driven GLODF susceptibility assessment indicator system responding to climate change that considers the complete process of GLODF formation,incorporating relevant parameters about upstream,themselves,and downstream of glacial ***,to mitigate subjective factors associated with traditional evaluation methods,we developed three novel hybrid machine-learning models by integrating classic machine-learning algorithms with the whale optimization algorithm(WOA)to delineate the distribution of GLODF susceptibility in the *** the hybrid models effectively predicted the GLODFs occurrence,with the WOA-SVC model demonstrating the highest prediction *** 34%of the catchments exhibit high and very high susceptibility levels,primarily concentrated along the north and south sides of the Himalayan ridge,particularly in the eastern and central *** capturing the physical formation process of hazards,such as topographic potential(highest relative importance value of 40%),can precisely identify GLODF.A total of 128 catchments pose potential transboundary threats,with 24 classified as having a very high susceptibility level and 25 as having a high susceptibility ***,the border region between China and Nepal is a prominent hotspot for transboundary threats of *** findings can provide valuable clues for disaster prevention,mitigation,and cross-border coordination in the Himalayas.

关键词： Glacial lake outburst debris flow Susceptibility assessment Climate change Himalayas

A new portable open-path instrument for ambient NH_(3) and on-road emission measurements

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Journal of Environmental Sciences 2024年第2期136卷 606-614页

作者： Wenhao Dai Shanshan Wang Sanbao Zhang Jian Zhu Chuanqi Gu Zhibin Sun Ruibin Xue bin zhou Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200438China Institute of Eco-Chongming(IEC) Shanghai 202162China Institute of Atmospheric Sciences Fudan UniversityShanghai 200433China

Increased attentions to vehicle emission of NH_(3)have been paid since it is generally regarded as an important source in urban ***,we developed a movable instrument based on Differential Optical Absorption Spectroscopy(DOAS)principle for detecting on-road NH_(3),which can avoid the losses in the sampling process attributed to the non-sampling *** this mobile DOAS,the temporal resolution,detection limit and relative error for NH_(3)were 1 min,2.29 ppbv and 4.57%±2.44%,*** employed to the on-road measurements along the arterial highway in Shanghai,the spatial distributions of NH_(3)and NO were obtained,and their dependence of traffic and road conditions were *** slopes of linear regression between NH_(3)and NO were 0.40,0.02 and 0.07 on the Middle Ring Road,Outer Ring Road and Chongming Island Ring *** indicates that light gasoline vehicles(LGVs)were found to be the main contributor to NH_(3)emissions,while heavy-duty diesel vehicles(HDVs)mainly emitted *** on the measured NH_(3)in the tunnel,the mileagebased NH_(3)emission factor per vehicle was estimated to be 17.9±6.3 mg/*** reported open-path instrument can be broadly used in on-road pollutant monitoring or vehicle emissions,and the measurements can reveal the real situation of emission characteristics,even find the abnormal operations of vehicle catalyst system.

关键词： Ammonia Traffic emissions DOAS Emission factor Mobile measurements

维普期刊数据库

Vitamin D,selenium,and antidiabetic drugs in the treatment of type 2 diabetes mellitus with Hashimoto's thyroiditis

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World Journal of Diabetes 2024年第2期15卷 209-219页

作者： Fen Feng bin zhou Ci-La zhou Ping Huang Gang Wang Kuang Yao School of Pharmacy Shaoyang UniversityShaoyang 422099Hunan ProvinceChina Department of Endocrinology The Central Hospital of ShaoyangShaoyang 422099Hunan ProvinceChina

BACKGROUND Diabetes and thyroiditis are closely *** occur in combination and cause significant damage to the *** is no clear treatment for type-2 diabetes mellitus(T2DM)with Hashimoto's thyroiditis(HT).While single symptomatic drug treatment of the two diseases is less effective,combined drug treatment may improve *** To investigate the effect of a combination of vitamin D,selenium,and hypoglycemic agents in T2DM with *** This retrospective study included 150 patients with T2DM and HT treated at The Central Hospital of Shaoyang from March 2020 to February *** patients were assigned to the control group,test group A,and test group B according to different treatment *** control group received low-iodine diet guidance and hypoglycemic drug *** group A received the control treatment plus vitamin D *** group B received the group A treatment plus *** levels of markers of thyroid function[free T3(FT3),thyroid stimulating hormone(TSH),free T4(FT4)],autoantibodies[thyroid peroxidase antibody(TPOAB)and thyroid globulin antibody(TGAB)],blood lipid index[low-density lipoprotein cholesterol(LDL-C),total cholesterol(TC),triacylglycerol(TG)],blood glucose index[fasting blood glucose(FBG),and hemoglobin A1c(HbA1c)]were measured pre-treatment and 3 and 6 months after *** relationships between serum 25-hydroxyvitamin D3[25(OH)D3]level and each of these indices were *** The levels of 25(OH)D3,FT3,FT4,and LDL-C increased in the order of the control group,test group A,and test group B(all P

关键词： Type-2 diabetes mellitus Hashimoto's thyroiditis Vitamin D Selenium agent Hypoglycemic drugs Curative effect

ROS Balance Autoregulating Core-Shell CeO_(2)@ZIF-8/Au Nanoplatform for Wound Repair

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Nano-Micro Letters 2024年第8期16卷 341-361页

作者： Xi zhou Quan zhou Zhaozhi He Yi Xiao Yan Liu Zhuohang Huang Yaoji Sun Jiawei Wang Zhengdong Zhao Xiaozhou Liu bin zhou Lei Ren Yu Sun Zhiwei Chen Xingcai Zhang The Higher Educational Key Laboratory for Biomedical Engineering of Fujian Province Research Center of Biomedical Engineering of XiamenDepartment of BiomaterialsCollege of MaterialsXiamen UniversityXiamen 361005People’s Republic of China Department of Electronic Science Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance ResearchSchool of Electronic Science and EngineeringXiamen UniversityXiamen 361005People’s Republic of China John A Paulson School of Engineering and Applied Sciences Harvard UniversityCambridgeMA 02138USA Department of Otorhinolaryngology Union Hospital of Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022People’s Republic of China NO.1 Middle School Affiliated to Central China Normal University Wuhan 430223People’s Republic of China

Reactive oxygen species(ROS)plays important roles in living *** ROS is a double-edged sword,which can eliminate drug-resistant bacteria,but excessive levels can cause oxidative damage to cells.A core–shell nanozyme,Ce O_(2)@ZIF-8/Au,has been crafted,spontaneously activating both ROS generating and scavenging functions,achieving the multifaceted functions of eliminating bacteria,reducing inflammation,and promoting wound *** Au Nanoparticles(NPs)on the shell exhibit high-efficiency peroxidase-like activity,producing ROS to kill ***,the encapsulation of Ce O_(2) core within ZIF-8 provides a seal for temporarily limiting the superoxide dismutase and catalase-like activities of Ce O_(2) ***,as the ZIF-8 structure decomposes in the acidic microenvironment,the Ce O_(2) core is gradually released,exerting its ROS scavenging activity to eliminate excess ROS produced by the Au *** two functions automatically and continuously regulate the balance of ROS levels,ultimately achieving the function of killing bacteria,reducing inflammation,and promoting wound *** innovative ROS spontaneous regulators hold immense potential for revolutionizing the field of antibacterial agents and therapies.

关键词： Metal-organic framework(MOF) Reactive oxygen species(ROS) Cerium dioxide Au nanoparticles Wound healing

维普期刊数据库

Aerodynamic Features of High-Speed Maglev Trains with Different Marshaling Lengths Running on a Viaduct under Crosswinds

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 975-996页

作者： Zun-Di Huang Zhen-bin zhou Ning Chang Zheng-Wei Chen Su-Mei Wang School of Rail Transportation Wuyi UniversityJiangmen529020China National Rail Transit Electrification and Automation Engineering Technology Research Center(Hong Kong Branch) The Hong Kong Polytechnic UniversityHong Kong999077China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong999077China

The safety and stability of high-speed maglev trains traveling on viaducts in crosswinds critically depend on their aerodynamic ***,this paper uses an improved delayed detached eddy simulation(IDDES)method to investigate the aerodynamic features of high-speed maglev trains with different marshaling lengths under *** effects of marshaling lengths(varying from 3-car to 8-car groups)on the train’s aerodynamic performance,surface pressure,and the flow field surrounding the train were investigated using the three-dimensional unsteady compressible Navier-Stokes(N-S)*** results showed that the marshaling lengths had minimal influence on the aerodynamic performance of the head and middle ***,the marshaling lengths are negatively correlated with the time-average side force coefficient(CS)and time-average lift force coefficient(Cl)of the tail *** to the tail car of the 3-car groups,the CS and Cl fell by 27.77%and 18.29%,respectively,for the tail car of the 8-car *** is essential to pay more attention to the operational safety of the head car,as it exhibits the highest time average ***,the mean pressure difference between the two sides of the tail car body increased with the marshaling lengths,and the side force direction on the tail car was opposite to that of the head and middle ***,the turbulent kinetic energy of the wake structure on the windward side quickly decreased as marshaling lengths increased.

关键词： High-speed maglev train marshaling lengths crosswinds aerodynamic features