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Active fault-tolerant tracking control of a quadrotor with model uncertainties and actuator faults

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Frontiers of Information Technology & Electronic Engineering 2019年第1期20卷 95-106页

作者： Yu-jiang ZHONG Zhi-xiang LIU You-min ZHANG Wei ZHANG jun-yi zuo School of Aeronautics Northwestern Polytechnical University Department of Mechanical Industrial and Aerospace Engineering Concordia University

This paper presents a reliable active fault-tolerant tracking control system(AFTTCS) for actuator faults in a quadrotor unmanned aerial vehicle(QUAV). The proposed AFTTCS is designed based on a well-known model reference adaptive control(MRAC) framework that guarantees the global asymptotic stability of a QUAV system. To mitigate the negative impacts of model uncertainties and enhance system robustness, a radial basis function neural network is incorporated into the MRAC scheme for adaptively identifying the model uncertainties online and modifying the reference model. Meanwhile, actuator dynamics are considered to avoid undesirable performance degradation. Furthermore, a fault detection and diagnosis estimator is constructed to diagnose lossof-control-effectiveness faults in actuators. Based on the fault information, a fault compensation term is added to the control law to compensate for the adverse effects of actuator faults. Simulation results show that the proposed AFTTCS enables the QUAV to track the desired reference commands in the absence/presence of actuator faults with satisfactory performance.

关键词： Model reference adaptive control Neural network Quadrotor Fault-tolerant control Fault detection and diagnosis

Navigating the safe operation of high-voltage cathodes:Challenges and strategies

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Nano Research 2024年第10期17卷 8694-8705页

作者： Yue Sun Changjian zuo yi-Chun Lu Electrochemical Energy and Interfaces Laboratory Department of Mechanical and Automation EngineeringThe Chinese University of Hong KongHong Kong 999077China

Lithium-ion batteries play a crucial role in storing energy for renewable sources and electric vehicles,yet face challenges related to insufficient energy *** the working-voltage of cathodes is promising to boost the energy density of batteries by increasing both the output voltage and capacity of cathode,which however could compromise life cycle and *** review provides a comprehensive summary of essential factors governing pathways of cathode-induced thermal runaway,including electrolyte decomposition,phase transitions,and crosstalk-induced *** and electrolyte modifications aimed at mitigating parasitic reactions and preventing crosstalk were also *** review concludes with insights into the future application of these strategies,providing a comprehensive perspective on the realization of high-energy and safe batteries.

关键词： battery safety high-voltage cathode lithium-ion battery thermal runaway

A New Test for Large Dimensional Regression Coefficients

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Open Journal of Statistics 2011年第3期1卷 212-216页

作者： june Luo yi-jun zuo 不详

In the article, hypothesis test for coefficients in high dimensional regression models is considered. I develop simultaneous test statistic for the hypothesis test in both linear and partial linear models. The derived test is designed for growing p and fixed n where the conventional F-test is no longer appropriate. The asymptotic distribution of the proposed test statistic under the null hypothesis is obtained.

关键词： High Dimension Ridge Regression Hypothesis Test Partial Linear Model Asymptotic

Selective adsorption of tetracycline by β-CD-immobilized sodium alginate aerogel coupled with ultrafiltration for reclaimed water

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Chinese Journal of Chemical Engineering 2024年第4期68卷 27-34页

作者： Xi Quan jun Zhang Linlin yin Wei zuo Yu Tian State Key Laboratory of Urban Water Resource and Environment(SKLUWRE) School of EnvironmentHarbin Institute of TechnologyHarbin 150090China

In this work,a novel composite material based on β-cyclodextrin-immobilized sodium alginate aerogel(β-CD/NaAlg) was developed utilizing cross-linker of epichlorohydrin and applied as an adsorbent to remove tetracycline antibiotics from reclaimed wastewater.A series of characterizations were utilized to confirm the successful synthesis of the adsorbent and this β-CD/NaAlg presented a three-dimensional network at the nanoscale or *** optimal conditions(pH=4,t=8 h,β-CD:NaAlg=9,adsorbent dosage = 1.5 g·L-1),the maximum removal rate of β-CD/NaAlg to tetracycline was 70%.The adsorption behavior of tetracycline on β-CD/NaAlg conformed to the Freundlich isotherm model(R2=0.9977) and the pseudo-second-order kinetic model(R^(2)=0.9993).Moreover,the adsorbent still removed 55.3% of tetracycline after five ***,the adsorbent was integrated with ultrafiltration to adsorb tetracycline antibiotics from simulated reclaimed wastewater,and the removal rate of tetracycline reached 78.9% within 2 *** existence of Cr(Ⅵ) had a negligible impact on tetracycline removal,while the presence of humic acid exhibited a promoting *** possible adsorption mechanisms were also elucidated through X-ray photoelectron spectroscopy and density functional theory *** summary,β-CD/NaAlg represents an environmentally friendly,efficient,and sustainable adsorbent for removing tetracycline antibiotics from reclaimed water.

关键词： b-CD/NaAlg aerogel Covalent grafting Tetracycline antibiotics Ultrafiltration Selective adsorption Reclaimed water

Some Convergence Properties for Weighted Sums of Martingale Difference Random Vectors

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1127-1142页

作者： yi WU Xue jun WANG School of Big Data and Artificial Intelligence Chizhou UniversityChizhou 247000P.R.China School of Big Data and Statistics Anhui UniversityHefei 230601P.R.China

Let{X_(ni),F_(ni);1≤i≤n,n≥1}be an array of R^(d)martingale difference random vectors and{A_(ni),1≤i≤n,n≥1}be an array of m×d matrices of real *** this paper,the Marcinkiewicz-Zygmund type weak law of large numb... 详细信息

关键词： Martingale difference random vectors weighted sums Marcinkiewicz–Zygmund type weak law of large numbers complete convergence strong law of large numbers multivariate simple linear regression model

Microglia Suppresses Breast Cancer Brain Metastasis via a Pro-inflammatory Response

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Neuroscience Bulletin 2024年第7期40卷 1034-1036页

作者： Shengbo Chen yi-jun Liu Department of Neurobiology of Affiliated Mental Health Center and Hangzhou Seventh People's Hospital and School of Brain Science and Brain Medicine Zhejiang University School of MedicineHangzhou 310058China Liangzhu Laboratory MOE Frontier Science Center for Brain Science and Brain-machine IntegrationState Key Laboratory of Brain-machine IntelligenceZhejiang University1369 West Wenyi RoadHangzhou 311121China NHC and CAMS Key Laboratory of Medical Neurobiology Zhejiang UniversityHangzhou 310058China

Due to the obstacle of the blood-brain barrier(BBB)for drug delivery[1],breast cancer brain metastasis(BCBM)represents a worldwide health challenge with high *** BCBM formation and progression,brain metastases(BrMs)secret various factors,including cytokines and exosomes,and trigger the infiltration of tumours-associated macrophages(TAMs),which in turn become important components of brain tumour microenvironments(TME).

关键词： mortality tumour Breast

Diagenetic evolution and reservoir quality of the Oligocene sandstones in the Baiyun Sag, Pearl River Mouth Basin, South China Sea

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Acta Oceanologica Sinica 2024年第2期43卷 67-82页

作者： Bing Tian Shanshan zuo Youwei Zheng Jie Zhang Jiayu Du jun Tang Institute of Mining and Coal Inner Mongolia University of Science and TechnologyBaotou 014010China Institute of Science Inner Mongolia University of Science and TechnologyBaotou 014010China

The Oligocene Zhuhai sandstones are significant reservoirs for hydrocarbons in the Baiyun Sag, South China *** effective appraisal, exploration and exploitation of such a deep-water hydrocarbon sandstone, samples of five wells from depths of 850 m to 3 000 m were studied. A series of comprehensive petrographic and geochemical analyses were performed to unravel the diagenetic features and their impact on the reservoir ***, the sandstones are dominated by feldspathic litharenites and lithic arenites with fine to medium grain sizes and moderate to good sorting. The reservoir quality varies greatly with a range of porosity from 0.2% to 36.1% and permeability from 0.016 ×10~(–3) μm~2 to 4 301 ×10~(–3) μm~2, which is attributed to complex diagenetic evolution related to sedimentary facies;these include compaction, cementation of calcite, dolomite, siderite and framboidal pyrite in eogenetic stage;further compaction, feldspar dissolution, precipitation of ferrocalcite and ankerite, quartz cements, formation of kaolinite and its illitization, precipitation of albite and nodular pyrite, as well as hydrocarbon charge in mesogenetic stage. The dissolution of feldspar and illitization of kaolinite provide internal sources for the precipitation of quartz cement, while carbonate cements are derived from external sources related to interbedded mudstones and deep fluid. Compaction is the predominant factor in reducing the total porosity, followed by carbonate cementation that leads to strong heterogeneity. Feldspar dissolution and concomitant quartz and clay cementation barely changes the porosity but significantly reduces the *** high-quality reservoirs can be concluded as medium-grained sandstones lying in the central parts of thick underwater distributary channel sandbodies(>2 m) with a high content of detrital quartz but low cement.

关键词： Baiyun Sag Oligocene Zhuhai Formation diagenesis reservoir quality

Oxidation Resistance of In Situ Reaction/Hot Pressing Synthesized Ti_(2)AlC-20%TiB_(2) Composite at 600-900℃in Air

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 739-748页

作者： Wenting Wang Jingjun Xu jun zuo Ke Ma Yang Li Guangqi He Meishuan Li Shengyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China

The oxidation behavior and kinetics of Ti_(2)AlC-20vol.%TiB_(2) composite at 600-900℃ in air were *** results showed that the oxidation kinetics of the composite followed a logarithmic law within the given temperature range,which indicated that the composites had excellent oxidation *** selective oxidation of Al in Ti_(2)AlC was greatly enhanced,which facilitated the formation of a continuous and dense protective layer of Al_(2)O_(3).Meanwhile,the existence of molten B_(2)O_(3) inhibited the outward diffusion of Ti and inward diffusion of oxygen,which prevented the growth of anatase TiO_(2) at 600℃ and rutile TiO_(2) at 700-900℃.Therefore,the incorporation of TiB_(2) completely inhibited the abnormally rapid oxidation of bulk Ti_(2)AlC at 600℃ and improved its oxidation resistance at 700-900℃.

关键词： MAX phase Ti_(2)AlC-TiB_(2)composite Intermediate temperature oxidation Oxidation kinetics

A Stroke-Limitation AMD Control System with Variable Gain and Limited Area for High-Rise Buildings

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工程与科学中的计算机建模(英文) 2024年第1期138卷 865-884页

作者： zuo-Hua Li Qing-Gui Wu jun Teng Chao-jun Chen School of Civil and Environmental Engineering Harbin Institute of Technology(Shenzhen)Shenzhen518055China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong100872China

Collisions between a moving mass and an anti-collision device increase structural responses and threaten structural *** active mass damper(AMD)with stroke limitations is often used to avoid ***,a strokelimited AMD control system with a fixed limited area shortens the available AMD stroke and leads to significant control *** solve this problem,the design approach with variable gain and limited area(VGLA)is proposed in this ***,the boundary of variable-limited areas is calculated based on the real-time status of the moving *** variable gain(VG)expression at the variable limited area is deduced by considering the saturation of AMD ***,numerical simulations of a stroke-limited AMD control system with VGLA are conducted on a high-rise building *** numerical simulations show that the proposed approach has superior strokelimitation performance compared with a stroke-limited AMD control system with a fixed limited ***,the proposed approach is validated through experiments on a four-story steel frame.

关键词： High-rise buildings active control stroke limitations variable gain variable limited area