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Chattering-free sliding mode control with unidirectional auxiliary surfaces for miniature helicopters

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International Journal of Intelligent Computing and Cybernetics 2012年第3期5卷 421-438页

作者： Jian Fu Wen-hua Chen qing-xian wu Department of Automation Nanjing University of Aeronautics and AstronauticsNanjingChina Department of Aeronautical and Automotive Engineering Loughborough UniversityLoughboroughUK

Purpose-This article proposes a chattering-free sliding mode control scheme with unidirectional auxiliary surfaces(UAS-SMC)for small miniature autonomous helicopters(Trex 250).Design/methodology/approach-The proposed UAS-SMC scheme consists of a nested sequence of rotor dynamics,angular rate,Euler angle,velocity and position ***-It is demonstrated that the UAS-SMC strategy can eliminate the chattering phenomenon exhibiting in the convenient SMC method and achieve a better approaching ***/value-The proposed control strategy is implemented on the helicopter and flight tests clearly demonstrate that a much better performance could be achieved,compared with convenient SMC schemes.

关键词： Unmanned aircraft Approaching speed Flight control Sliding mode control Helicopters Chattering

Sensor Fault Diagnosis for a Class of Time Delay Uncertain Nonlinear Systems Using Neural Network

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International Journal of Automation and computing 2008年第4期5卷 401-405页

作者： Mou Chen Chang-Sheng Jiang qing-xian wu College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016PRC

In this paper,a sliding mode observer scheme of sensor fault diagnosis is proposed for a class of time delay nonlinear systems with input uncertainty based on neural *** sensor fault and the system input uncertainty are assumed to be unknown but *** radial basis function (RBF) neural network is used to approximate the sensor *** on the output of the RBF neural network,the sliding mode observer is *** the Lyapunov method,a criterion for stability is given in terms of matrix ***,an example is given for illustrating the availability of the fault diagnosis based on the proposed sliding mode observer.

关键词： Uncertain nonlinear system time delay radial basis function (RBF) neural network sliding mode observer fault diag-nosis.

Plasmonic tandem heterojunctions enable high-efficiency charge transfer for broad spectrum photocatalytic hydrogen production

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Journal of Energy Chemistry 2025年第1期100卷 710-720页

作者： Wenxuan Chen Xiu-qing Qiao Guo Hui Bojing Sun Dongfang Hou Meidi Wang Xueqian wu Tao wu Dong-Sheng Li College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials China Three Gorges University Hubei Three Gorges Laboratory College of Chemistry and Materials Science and Guangdong Provincial Key Laboratory of Supramolecular Coordination Chemistry Jinan University

Rational engineering of semiconductor photocatalysts for efficient hydrogen production is of great significance but still challenging,primarily due to the limitations in charge transfer ***,a fascinating plasmonic tandem heterojunction with the hc-CdS/Mo2C@C heterostructure is aimfully prepared for effectively promoting the charge separation kinetics of the CdS photocatalyst via the synergistic strategy of phase junction,Schottky junction,and photothermal *** difference in atomic configuration between cubic-CdS （c-CdS） and hexagonal-CdS （h-CdS） leads to effective charge separation through a typical Ⅱ charge transfer mechanism,and plasmonic Schottky junction further extracts the electrons in the hc-CdS phase junction to realize gradient charge ***,the photothermal effect of Mo2C@C helps to expand the light absorption,accelerate charge transfer kinetics,and reduce the hydrogen evolution energy *** carbon layer provides a fast channel for charge transfer and protects the photocatalyst from *** a result,the optimized hc-CMC photocatalyst exhibits a significantly high photocatalytic H2production activity of 28.63 mmol/g/h and apparent quantum efficiency of 61.8%,surpassing most of the reported *** study provides a feasible strategy to enhance the charge transfer kinetics and photocatalytic activity of CdS by constructing plasmonic tandem heterogeneous junctions.

关键词： Heterojunctions LSPR Photocatalyst Phase junction Schottky junction Photothermal effect

Insights into spinal muscular atrophy from molecular biomarkers

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Neural Regeneration Research 2025年第7期20卷 1849-1863页

作者： Xiaodong Xing Xinzhu Liu xiandeng Li Mi Li xian wu Xiaohui Huang Ajing Xu Yan Liu Jian Zhang Department of Clinical Pharmacy Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina College of Pharmacy Chongqing Medical UniversityChongqingChina

Spinal muscular atrophy is a devastating motor neuron disease characterized by severe cases of fatal muscle *** is one of the most common genetic causes of mortality among infants aged less than 2 *** research is currently receiving more attention,and new candidate biomarkers are constantly being *** review initially discusses the evaluation methods commonly used in clinical practice while briefly outlining their respective pros and *** also describe recent advancements in research and the clinical significance of molecular biomarkers for spinal muscular atrophy,which are classified as either specific or non-specific *** review provides new insights into the pathogenesis of spinal muscular atrophy,the mechanism of biomarkers in response to drug-modified therapies,the selection of biomarker candidates,and would promote the development of future ***,the successful utilization of biomarkers may facilitate the implementation of gene-targeting treatments for patients with spinal muscular atrophy.

关键词： biomarkers disease progression gene-targeting therapy neurofilaments Nusinersen spinal muscular atrophy(SMA) survival motor neuron therapeutic evaluation treatment outcomes

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提高电场积分方程求解精度的有效方法

系统工程与电子技术 2009年第11期31卷 2553-2555页

作者：宋开宏张庆华吴先良安徽大学计算智能与信号处理教育部重点实验室安徽合肥230039

为了提高矩量法求解电场积分方程的精度和效率,提出了一种改善电场积分方程求解精度的新方法。该方法首先在粗网格剖分下由电场积分方程求出不精确的感应电流,然后由此不精确的感应电流可求得散射体上任意一点处的散射磁场,最后由该点... 详细信息

为了提高矩量法求解电场积分方程的精度和效率,提出了一种改善电场积分方程求解精度的新方法。该方法首先在粗网格剖分下由电场积分方程求出不精确的感应电流,然后由此不精确的感应电流可求得散射体上任意一点处的散射磁场,最后由该点处的总磁场求出该点处的高精度感应电流。将该方法应用于无限长导体圆柱和方柱的散射计算中,数值结果表明了在粗网格剖分下该方法的有效性和高精度性。

关键词：电磁散射矩量法电场积分方程感应电流网格尺寸

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聚乙烯的杨氏模量及力常数的计算

武汉大学学报（理学版） 2004年第5期50卷 551-554页

作者：韦荣斌王小清邹宪武金准智武汉大学物理科学与技术学院湖北武汉430072

用不同于通常的计算力常数的方法,采用适于准一维链的力场,将势能表示为力常数的函数,并用STO 3G基的从头计算方法计算总能,由此求得杨氏模量和力常数.所得结果与实验符合很好,说明这种计算力常数的方法是有效的.所提出的用以拟合聚乙... 详细信息

用不同于通常的计算力常数的方法,采用适于准一维链的力场,将势能表示为力常数的函数,并用STO 3G基的从头计算方法计算总能,由此求得杨氏模量和力常数.所得结果与实验符合很好,说明这种计算力常数的方法是有效的.所提出的用以拟合聚乙烯能量曲面的表达式能达到很高精度(误差在10-5Hartree左右),本文为高分子聚合物势能曲面拟合提供了一个简单而有效的方法.

关键词：聚乙烯杨氏模量力常数从头计算高分子聚合物材料

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干旱荒漠区沙地衬膜樟子松育苗技术研究

水土保持学报 2003年第3期17卷 170-173页

作者：满多清徐先英吴春荣杨自辉刘世增甘肃省治沙研究所甘肃武威733000

沙地衬膜试验结果表明:衬膜沙地栽植的樟子松苗木当年平均成活率高于对照地;不同越冬处理的苗木越冬率从大到小为埋土,衬膜深度90cm露地,衬膜深度70cm露地,不衬膜露地越冬。高生长量显示出第一年、第二年衬膜苗高于对照苗,而第三年衬膜... 详细信息

沙地衬膜试验结果表明:衬膜沙地栽植的樟子松苗木当年平均成活率高于对照地;不同越冬处理的苗木越冬率从大到小为埋土,衬膜深度90cm露地,衬膜深度70cm露地,不衬膜露地越冬。高生长量显示出第一年、第二年衬膜苗高于对照苗,而第三年衬膜苗弱于对照苗。灌水量相同的条件下,衬膜苗在生长季节利于苗木旺盛生长;秋冬春季苗地土壤水分过多,地块低洼处的苗木保存率降低,生长量也较低,对照地苗木则相反。建议通过控制灌水量,积极探索衬膜种植的栽培学技术,创造条件,实行少量多次的定额灌溉,是干旱区进一步提高樟子松育苗成活率、保存率的一种新的有效途径。

关键词：干旱荒漠区樟子松育苗技术沙地衬膜苗木成活率苗木保存率生长量少量多次定额灌溉

Resilient and Safe Platooning Control of Connected Automated Vehicles Against Intermittent Denial-of-Service Attacks

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IEEE/CAA Journal of Automatica Sinica 2023年第5期10卷 1234-1251页

作者： Xiaohua Ge qing-Long Han qing wu xian-Ming Zhang the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia the School of Engineering and Technology Central Queensland UniversityRockhampton QLD 4701Australia

Connected automated vehicles(CAVs)serve as a promising enabler for future intelligent transportation systems because of their capabilities in improving traffic efficiency and driving safety,and reducing fuel consumption and vehicle emissions.A fundamental issue in CAVs is platooning control that empowers a convoy of CAVs to be cooperatively maneuvered with desired longitudinal spacings and identical velocities on *** paper addresses the issue of resilient and safe platooning control of CAVs subject to intermittent denial-of-service(DoS)attacks that disrupt vehicle-to-vehicle ***,a heterogeneous and uncertain vehicle longitudinal dynamic model is presented to accommodate a variety of uncertainties,including diverse vehicle masses and engine inertial delays,unknown and nonlinear resistance forces,and a dynamic platoon ***,a resilient and safe distributed longitudinal platooning control law is constructed with an aim to preserve simultaneous individual vehicle stability,attack resilience,platoon safety and ***,a numerically efficient offline design algorithm for determining the desired platoon control law is developed,under which the platoon resilience against DoS attacks can be maximized but the anticipated stability,safety and scalability requirements remain ***,extensive numerical experiments are provided to substantiate the efficacy of the proposed platooning method.

关键词： Connected automated vehicles(CAVs) cooperative adaptive cruise control denial-of-service(DoS)attacks resilient control vehicle platooning vehicle-to-vehicle communication

Infiltration by monocytes of the central nervous system and its role in multiple sclerosis: reflections on therapeutic strategies

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Neural Regeneration Research 2025年第3期20卷 779-793页

作者： Guangyong Zhang qing Yao Chubing Long Pengcheng Yi Jiali Song Luojia wu Wei Wan Xiuqin Rao Yue Lin Gen Wei Jun Ying Fuzhou Hua Department of Anesthesiology the Second Affiliated Hospital of Nanchang UniversityNanchangJiangxi ProvinceChina Key Laboratory of Anesthesiology of Jiangxi Province NanchangJiangxi ProvinceChina

Mononuclear macrophage infiltration in the central nervous system is a prominent feature of neuroinflammation. Recent studies on the pathogenesis and progression of multiple sclerosis have highlighted the multiple roles of mononuclear macrophages in the neuroinflammatory process. Monocytes play a significant role in neuroinflammation, and managing neuroinflammation by manipulating peripheral monocytes stands out as an effective strategy for the treatment of multiple sclerosis, leading to improved patient outcomes. This review outlines the steps involved in the entry of myeloid monocytes into the central nervous system that are targets for effective intervention: the activation of bone marrow hematopoiesis, migration of monocytes in the blood, and penetration of the blood–brain barrier by monocytes. Finally, we summarize the different monocyte subpopulations and their effects on the central nervous system based on phenotypic differences. As activated microglia resemble monocyte-derived macrophages, it is important to accurately identify the role of monocyte-derived macrophages in disease. Depending on the roles played by monocyte-derived macrophages at different stages of the disease, several of these processes can be interrupted to limit neuroinflammation and improve patient prognosis. Here, we discuss possible strategies to target monocytes in neurological diseases, focusing on three key aspects of monocyte infiltration into the central nervous system, to provide new ideas for the treatment of neurodegenerative diseases.

关键词： blood–brain barrier macrophages monocytes multiple sclerosis neuroinflammation review therapy