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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 649-660页

作者： Meilin li Yue long Tieshan li Hongjing liang C.l.philip Chen the School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731China IEEE the Yangtze Delta Region Institute University of Electronic Science and Technology of ChinaHuzhou 313000 the laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing 100089China the School of Computer Science and Engineering South China University of TechnologyGuangzhou 510006

This paper investigates the consensus control of multi-agent systems(MASs) with constrained input using the dynamic event-triggered mechanism(ETM).Consider the MASs with small-scale networks where a centralized dynamic ETM with global information of the MASs is first ***,a distributed dynamic ETM which only uses local information is developed for the MASs with large-scale *** is shown that the semi-global consensus of the MASs can be achieved by the designed bounded control protocol where the Zeno phenomenon is eliminated by a designable minimum inter-event *** addition,it is easier to find a trade-off between the convergence rate and the minimum inter-event time by an adjustable ***,the results are extended to regional consensus of the MASs with the bounded control *** simulations show the effectiveness of the proposed approach.

关键词： Constrained input designable minimum inter-event time directed communication topology dynamic event-triggered mechanism MASs consensus control

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Adaptive neural network control of a 2-DOF helicopter system considering input constraints and global prescribed performance

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Science China(Information Sciences) 2024年第7期67卷 224-239页

作者： Zhijia ZHAO Jiale WU Zhijie lIU We HE C.l.philip CHEN School of Mechanical and Electrical Engineering Guangzhou University School of Intelligence Science and Technology and Key laboratory of Intelligent Bionic Unmanned Systems of Ministry of Education University of Science and Technology Beijing School of Computer Science and Engineering South China University of Technology Pazhou lab

In this study, an adaptive neural network(NN) control is proposed for nonlinear two-degree-offreedom(2-DOF) helicopter systems considering the input constraints and global prescribed ***, radial basis function NN(RBFNN) is employed to estimate the unknown dynamics of the helicopter system. Second, a smooth nonaffine function is exploited to approximate and address nonlinear constraint functions. Subsequently, a new prescribed function is proposed, and an original constrained error is transformed into an equivalent unconstrained error using the error transformation and barrier function transformation methods. The analysis of the established lyapunov function proves that the controlled system is globally uniformly bounded. Finally, the simulation and experimental results on a constructed Quanser's test platform verify the rationality and feasibility of the proposed control.

关键词： adaptive NN control 2-DOF helicopter global prescribed performance input constraints

A Practical Predefined-Time Stability Criterion and Its Application to Uncertain Nonlinear Systems

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Journal of Systems Science & Complexity 2024年

作者： XU Hao YU Dengxiu SUI Shuai XU Bowen CHEN C.l.philip Unmanned System Research Institute Northwestern Polytechnical University College of Science Liaoning University of Technology School of Artificial Intelligence Optics and Electronics Northwestern Polytechnical University School of Computer Science and Engineering South China University of Technology and Pazhou Lab

In this paper, the singularity-free predefined-time fuzzy adaptive tracking control problem is studied for non-strict feedback(NSF) nonlinear systems considering mismatched external disturbances. An innovative practical predefined-time stability(PPTS) criterion is proposed to provide the theoretical basis for subsequent control design. Compared to the existing predefined-time stability(PTS) criterion, this criterion has a broader application range and can solve the control design issues of nonlinear systems with system uncertainties. Fuzzy logic systems(FlSs) are employed to identify unknown nonlinear functions. Based on the backstepping control technology, a singularity-free predefined-time control(PTC) design method is proposed, in which the hyperbolic tangent function is utilized to avoid the singular problem, and the nature of fuzzy basis function is adopted to resolve the algebraic loop problem. The PPTS of the closed-loop NSF nonlinear system is proven with the lyapunov theory and the proposed PPTS criterion. Ultimately, the efficiency of the presented PTC design method is verified by several sets of simulations on a single link manipulator system.

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Boosting Adaptive Weighted Broad learning System for Multi-label learning

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IEEE/CAA Journal of Automatica Sinica 2024年第11期11卷 2204-2219页

作者： Yuanxin lin Zhiwen Yu Kaixiang Yang Ziwei Fan C.l.philip Chen the School of Computer Science and Engineering in South China University of Technology IEEE the Pengcheng laboratory

Multi-label classification is a challenging problem that has attracted significant attention from researchers, particularly in the domain of image and text attribute annotation. However, multi-label datasets are prone to serious intra-class and inter-class imbalance problems, which can significantly degrade the classification performance. To address the above issues, we propose the multi-label weighted broad learning system(MlW-BlS) from the perspective of label imbalance weighting and label correlation mining. Further, we propose the multi-label adaptive weighted broad learning system(MlAW-BlS) to adaptively adjust the specific weights and values of labels of MlW-BlS and construct an efficient imbalanced classifier set. Extensive experiments are conducted on various datasets to evaluate the effectiveness of the proposed model, and the results demonstrate its superiority over other advanced approaches.

关键词： Broad learning system label correlation mining label imbalance weighting multi-label imbalance

A novel homozygous missense variant in ARSK causes MPS X,a new subtype of mucopolysaccharidosis

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Genes & Diseases 2024年第3期11卷 87-90页

作者： Miao Sun Cornelia K.Kaminsky philip Deppe Mai-Brittllse Frederic M.Vaz Barbara Plecko Torben lubke linda M.Randolph Division of Genomic Medicine Department of Pathology and Laboratory MedicineChildren's Hospital Los Angeles/Keck School of Medicine of USCLos AngelesCA 90027USA Department of Radiology Children's Hospital Los Angeles/Keck School of Medicine of USCLos AngelesCA 90027USA Department of Chemistry BiochemistryBielefeld UniversityBielefeld 33615Germany Amsterdam UMC location University of Amsterdam Department of Clinical Chemistry and PediatricsLaboratory Genetic Metabolic DiseasesEmma Children's HospitalMeibergdreef 9Amsterdam 1100 DEthe Netherlands Amsterdam Gastroenterology Endocrinology Metabolism Inborn Errors of MetabolismAmsterdam 1105 BKthe Netherlands Core Facility Metabolomics Amsterdam UMC Location University of AmsterdamAmsterdam 1100DDthe Netherlands Department of Pediatrics Division of General PediatricsMedical Universityof GrazGraz8036Austria Division of Medical Genetics Department of PediatricsChildren's Hospital Los Angeles/Keck School of Medicine of USCLos AngelesCA 90027USA

Mucopolysaccharidoses(MPS)are a group of rare inborn errors of metabolism caused by defective lysosomal enzymes which prevent cells from degrading and recycling certain carbohydrates and fats,resulting in the storage of glycosaminoglycans in cells throughout the *** leads to multisystem abnormalities involving bone,connective tissues,brain,blood,spinal cord,skin,and other tissues.

关键词： metabolism doses polys

Unveiling a novel metal-to-metal transition in luH_(2):Critically challenging superconductivity claims in lutetium hydrides

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Matter and Radiation at Extremes 2024年第3期9卷 65-73页

作者： Dong Wang Ningning Wang Caoshun Zhang Chunsheng Xia Weicheng Guo Xia Yin Kejun Bu Takeshi Nakagawa Jianbo Zhang Federico Gorelli philip Dalladay-Simpson Thomas Meier Xujie lü liling Sun Jinguang Cheng Qiaoshi Zeng Yang Ding Ho-kwang Mao Center for High-Pressure Science and Technology Advanced Research Beijing 100094China Beijing National laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China Shanghai Key laboratory of Material Frontiers Research in Extreme Environments(MFree) Shanghai Advanced Research in Physical Sciences(SHARPS)Shanghai 201203China

Following the recent report by Dasenbrock-Gammon et al.[Nature 615,244–250(2023)]of near-ambient superconductivity in nitrogendoped lutetium trihydride(luH_(3-δ)N_(ε)),significant debate has emerged surrounding the composition and interpretation of the observed sharp resistance ***,we meticulously revisit these claims through comprehensive characterization and *** definitively identify the reported material as lutetium dihydride(luH_(2)),resolving the ambiguity surrounding its *** similar conditions(270–295 K and 1–2 GPa),we replicate the reported sharp decrease in electrical resistance with a 30%success rate,aligning with the observations by Dasenbrock-Gammon et ***,our extensive investigations reveal this phenomenon to be a novel pressure-induced metal-to-metal transition intrinsic to luH_(2),distinct from ***,nitrogen doping exerts minimal impact on this *** work not only elucidates the fundamental properties of luH_(2)andluH_(3),but also critically challenges the notion of superconductivity in these lutetium hydride *** findings pave the way for future research on lutetium hydride systems,while emphasizing the crucial importance of rigorous verification in claims of ambient-temperature superconductivity.

关键词： resistance hydride superconductivity

Prehospital transdermal glyceryl trinitrate for ultra- acute ischaemic stroke: data from the RIGHT- 2 randomised sham- controlled ambulance trial

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Stroke & Vascular Neurology 2024年第1期9卷 38-49,I0035-I0046页

作者： Jason philip Appleton lisa J Woodhouse Craig S Anderson Sandeep Ankolekar lesley Cala Mark Dixon Timothy J England Kailash Krishnan Grant Mair Keith W Muir John Potter Christopher I Price Marc Randall Thompson G Robinson Christine Roffe Else C Sandset Jeffrey l Saver Angela Shone Aloysius Niroshan Siriwardena Joanna M Wardlaw Nikola Sprigg philip M Bath Stroke University Hospitals Birmingham NHS Foundation TrustBirminghamUK Institute of Applied HealthResearch University of Birmingham College of Medical and Dental SciencesBirminghamUK Stroke Trials Unit Mental Health and Clinical NeurosciencesUniversity of NottinghamNottinghamUK Faculty of Medicine The George Institute for Global HealthSydneyNew South WalesAustralia The George Institute China at Peking University Health Science Center BeijingChina Neurology Royal Prince Alfred HospitalSydney Health PartnersSydneyNew South WalesAustralia Department of Neurology King's College Hospital NHS Foundation TrustLondonUK Faculty of Health and Medical Sciences University of Western AustraliaCrawleyWestern AustraliaAustralia East Midlands Ambulance Service NHS Trust NottinghamUK Stroke Queen's Medical CentreNottingham University Hospitals NHS TrustNottinghamUK Centre for Clinical Brain Sciences Dementia Research InstituteUniveristy of EdinburghEdinburghUK Institute of Neurology and Psychology University of GlasgowGlasgowUK Bob Champion Research and Education Building University of East AngliaNorwichUK Institute of Neuroscience Newcastle UniversityNewcastle upon TyneUK Department of Neurology Leeds Teaching Hospitals NHS TrustLeedsUK Department of Cardiovascular Sciences and NIHR leicester Biomedical Research Centre University of LeicesterLeicesterUK Stroke Research in Stoke Institute for Science and Technology in MedicineKeele UniversityStoke-on TrentUK Department of Neurology Oslo University HospitalOsloNorway Research and Development Norwegian Air Ambulance FoundationOsloNorway Department of Neurology and Comprehensive Stroke Center David Geffen School of MedicineUCLALos AngelesCaliforniaUSA Research and Graduate Services University of NottinghamNottinghamUK Community and Health Research Unit University of LincolnLincolnUK

Background The effect of transdermal glyceryl trinitrate(GTN,a nitrovasodilator)on clinical outcome when administered before hospital admission in suspected stroke patients is ***,we assess the safety and efficacy of GTN in the prespecified subgroup of patients who had an ischaemic stroke within the Rapid Intervention with Glyceryl trinitrate in Hypertensive stroke Trial-2(RIGHT-2).Methods RIGHT-2 was an ambulance-based multicentre sham-controlled blinded-endpoint study with patients randomised within 4hours of *** primary outcome was a shift in scores on the modified Rankin scale(mRS)at day *** outcomes included death;a global analysis(Wei-lachin test)containing Barthel Index,EuroQol-5D,mRS,telephone interview for cognitive status-modified and Zung depression scale;and neuroimaging-determined‘brain frailty’*** were reported as n(%),mean(SD),median[IQR],adjusted common OR(acOR),mean difference or Mann-Whitney difference(MWD)with 95%*** 597 of 1149(52%)patients had a final diagnosis of ischaemic stroke;age 75(12)years,premorbid mRS>2107(18%),Glasgow Coma Scale 14(2)and time from onset to randomisation 67[45,108]***‘brain frailty’was common:median score 2[2,3](range 0–3).At day 90,GTN did not influence the primary outcome(acOR for increased disability 1.15,95%CI 0.85 to 1.54),death or global analysis(MWD 0.00,95%CI-0.10 to 0.09).In subgroup analyses,there were non-significant interactions suggesting GTN may be associated with more death and dependency in participants randomised within 1hour of symptom onset and in those with more severe *** In patients who had an ischaemic stroke,ultra-acute administration of transdermal GTN in the ambulance did not improve clinical outcomes in a population with more clinical and radiological frailty than seen in previous in-hospital *** IS AlREADY KNOWN ON THIS TOPIC⇒Transdermal glyceryl trinitrate(GTN)was associat-ed with less death and dependency in those w

关键词： Glasgow nitrate random

地质和卫生科学联合评估尼日利亚手工掘金所致的儿童铅中毒

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环境与职业医学 2013年第9期30卷 689-689页

作者： Geoffrey S.Plumlee James T.Durant Suzette A.Morman Antonio Neri Ruth E.Wolf Carrie A.Dooyema philip l.hageman Heather A.lowers Gregory l.Fernette Gregory P.Meeker William M.Benzel Rhonda l.Driscoll Cyrus J.Berry James G.Crock Harland l.Goldstein Monique Adams Casey l.Bartrem Simba Tirima Behrooz Behbod Ian von lindern Mary Jean Brown

[背景]2010年,无国界医生组织发现尼日利亚西北部爆发与手工黄金加工相关的铅中毒。疫情已造成约400名幼儿死亡,数千人受影响。[目的]旨在进行一项跨地质和卫生科学的评估,以明确铅的来源和暴露途径,确定更多相关毒物和高危人群,并探讨... 详细信息

[背景]2010年,无国界医生组织发现尼日利亚西北部爆发与手工黄金加工相关的铅中毒。疫情已造成约400名幼儿死亡,数千人受影响。[目的]旨在进行一项跨地质和卫生科学的评估,以明确铅的来源和暴露途径,确定更多相关毒物和高危人群,并探讨全球类似的铅中毒发生的可能性。[方法]采用不同的方法,对矿石样品、来自村庄和家庭化合物中的土壤和清扫样品、植物性食物样品进行分析。[结果]富铅金矿石在开采前的自然风化形成大量、高度胃-生物可及性的碳酸铅。在所有类型的样品中发现相同的铅矿指纹,从而确定矿石处理过程造成了极大的污染,土壤/清扫样品中的铅高达185000×10-7,植物性食品中高达145×10-7。意外摄食经过手口传播的土壤和从呼吸道排出的灰尘是主要暴露途径。食用受到加工过程污染的水和食品可能铅摄入量较小,但这些仍然是重要的暴露途径。虽然幼儿遭受了最直接和最严重的后果,但研究结果表明,年龄较大的儿童、成年工人、孕妇和哺乳期婴儿也处于铅中毒的风险之中。汞、砷、锰、锑、二氧化硅结晶暴露对健康造成额外的威胁。[结论]研究结果为尼日利亚正在进行的工作提供了信息,以评估铅污染和铅中毒、治疗受害者、减少暴露以及治理污染。矿床地质、开采前风化以及新兴的手工采矿几种因素可能会综合导致全球其他地方类似的铅中毒灾难。

关键词：儿童铅中毒尼日利亚卫生科学手工地质无国界医生组织食物样品高危人群

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Advancing Evaluation of Microplastics Thresholds to Inform Water Treatment Needs and Risks

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Environment & Health 2024年第7期2卷 441-452页

作者： Omar S.Chowdhury philip J.Schmidt William B.Anderson Monica B.Emelko Department of Civil and Environmental Engineering University of Waterloo200 University Avenue WestWaterlooON N2L 3G1Canada

Although human health impacts of microplastics are not well understood,concern regarding chemical contaminants retained on or within them is *** water providers are increasingly asked about these risks,but strategies for evaluating them and the extent of treatment needed to manage them are currently *** can potentially induce health effects if the concentration of contaminants adsorbed to them exceeds predetermined drinking water guidelines(e.g.,Maximum Contaminant levels).The risk posed by microplastics due to adsorbed contaminants is difficult to determine,but a worst-case scenario can be evaluated by using adsorption ***,a“Threshold Microplastics Concentration”(TMC)framework is developed to evaluate whether waterborne microplastic concentrations can potentially result in the intake of regulated contaminants on/in microplastics at levels of human health concern and identify treatment targets for managing associated health *** the TMC does not indicate an immediate health risk;it informs the need for detailed risk assessment or further treatment evaluation to ensure particle removal targets are ***,the TMC concept and framework provide an updateable,science-based screening tool to determine if there is a need for detailed risk assessment or treatment modification due to waterborne microplastics in supplies used for potable water production.

关键词： drinking water treatment chemical contaminants adsorption capacity risk management maximum contaminant level

Effect of Dietary Components on the Shear Bond Strength of Orthodontics Brackets after Thermal Aging

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Open Journal of Stomatology 2024年第6期14卷 309-315页

作者： philip Punzalan Tanya Al Talib Anthony Fusco Neamat Hassan Abubakr School of Dental Medicine University of Nevada Las Vegas Nevada USA

Introduction: The stability of orthodontic brackets throughout orthodontic treatment plays a critical role in the treatment’s effectiveness. The present in vitro study was designed to assess the impact of various dietary components on the performance of orthodontic brackets. Methods: Metal orthodontic brackets were bonded to 66 extracted anterior teeth divided into groups based on the solution type: Milk, Gatorade, Cold Coffee, and a control group using water. Each group consisted of 20 teeth except for the control group, which included six teeth. The bracketed teeth were submerged in their respective solutions for 15 minutes three times daily at different intervals to mimic an in vivo environment and were stored in artificial saliva at room temperature (23?C). The specimens underwent artificial aging through 10,000 cycles of thermocycling (representing one clinical year) between 5?C and 55?C. Shade measurements were taken using a VITA Easy Shade device, capturing the classic shade and l*, a*, and b* values. Delta E values were calculated immediately post-bonding and after 7 days, 1 month, 1, and 2 clinical years. The shear bond strength of each bracket was measured using an ultra-tester machine. Results: After two clinical years, significant differences in ΔE color values were observed across all groups, with the most substantial change noted in teeth immersed in cold coffee. Brackets submerged in milk demonstrated lower shear bond strength than other solutions, whereas the control group exhibited the highest shear bond strength (P = 0.01). Conclusion: The study indicates that dietary components significantly influence tooth color stability and the shear bond strength of orthodontic brackets, underscoring the importance of considering these factors in orthodontic treatment planning.

关键词： Shear Bond Orthodontic Brackets Color Stability Thermal Aging