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Error-based adaptive optimal tracking control of nonlinear discrete-time systems

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Science China(Information Sciences) 2024年第1期67卷 154-167页

作者： Chun LI Jinliang dING Frank L.lewis Tianyou CHAI State Key Laboratory of Synthetical Automation for Process Industries Northeastern University UTA Research Institute The University of Texas at Arlington

In this paper,for the output tracking problem of nonlinear discrete-time systems,a performance index is newly defined using the adaptive dynamic programming(AdP) technique to completely eliminate tracking errors in *** contrast to traditional definitions of performance indices in other AdP-based methods,the proposed performance index is not only designed from the perspective of output tracking errors but also introduced errors of system states and control inputs at adjacent stages,which is suitable for practical situations in many industrial applications,such as the alumina production,the flotation process,and the mineral grinding *** proved that the obtained controller can make the system output fully track the given reference trajectory by applying the iterative criteria of the AdP *** addition,the proposed algorithm was implemented using a data-driven technique and neural networks to avoid analyzing and deducing the complicated dynamics of actual industrial ***,using historical data for a forced-circulation evaporation system in the alumina production process,the effect of the proposed approach was verified through a numerical simulation and compared with that of the proportional-integral controller.

关键词： adaptive dynamic programming iterative criteria performance index tracking errors tracking problem

Recent Progress in Reinforcement Learning and Adaptive dynamic Programming for Advanced Control Applications

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 18-36页

作者： ding Wang Ning Gao derong Liu Jinna Li Frank L.lewis IEEE the Faculty of Information Technology Beijing Key Laboratory of Computational Intelligence and Intelligent SystemBeijing Laboratory of Smart Environmental Protectionand Beijing Institute of Artificial IntelligenceBeijing University of TechnologyBeijing 100124China the School of System design and Intelligent Manufacturing Southern University of Science and TechnologyShenzhen 518055China the department of Electrical and Computer Engineering University of Illinois at ChicagoChicago IL 60607 USA the School of Information and Control Engineering Liaoning Petrochemical UniversityFushun 113001China the UTA Research Institute the University of Texas at ArlingtonArlington TX 76118 USA

Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(AdP) within the control community. This paper reviews recent developments in AdP along with RL and its applications to various advanced control fields. First, the background of the development of AdP is described, emphasizing the significance of regulation and tracking control problems. Some effective offline and online algorithms for AdP/adaptive critic control are displayed, where the main results towards discrete-time systems and continuous-time systems are surveyed, ***, the research progress on adaptive critic control based on the event-triggered framework and under uncertain environment is discussed, respectively, where event-based design, robust stabilization, and game design are reviewed. Moreover, the extensions of AdP for addressing control problems under complex environment attract enormous attention. The AdP architecture is revisited under the perspective of data-driven and RL frameworks,showing how they promote AdP formulation ***, several typical control applications with respect to RL and AdP are summarized, particularly in the fields of wastewater treatment processes and power systems, followed by some general prospects for future research. Overall, the comprehensive survey on AdP and RL for advanced control applications has d emonstrated its remarkable potential within the artificial intelligence era. In addition, it also plays a vital role in promoting environmental protection and industrial intelligence.

关键词： Adaptive dynamic programming(AdP) advanced control complex environment data-driven control event-triggered design intelligent control neural networks nonlinear systems optimal control reinforcement learning(RL)

Understanding the catalysis of chromium trioxide added magnesium hydride for hydrogen storage and Li ion battery applications

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Journal of Magnesium and Alloys 2024年第3期12卷 1117-1130页

作者： d.Pukazhselvan IhsanÇaha Catarina de Lemos Sergey M.Mikhalev Francis Leonard deepak duncan paul Fagg department of Mechanical Engineering TEMA-Centre for Mechanical Technology and AutomationUniversity of AveiroAveiro 3810-193Portugal LASI-Intelligent Systems Associate Laboratory Guimarães 4800-058Portugal Nanostructured Materials Group International Iberian Nanotechnology Laboratory(INL)Avenida Mestre Jose VeigaBraga 4715-330Portugal

This study explores how the chemical interaction between magnesium hydride(MgH_(2))and the additive CrO_(3) influences the hydrogen/lithium storage characteristics of MgH_(2).We have observed that a 5 wt.%CrO_(3) additive reduces the dehydrogenation activation energy of MgH_(2) by 68 kJ/mol and lowers the required dehydrogenation temperature by 80℃.CrO_(3) added MgH_(2) was also tested as an anode in an Li ion battery,and it is possible to deliver over 90%of the total theoretical capacity(2038 mAh/g).Evidence for improved reversibility in the battery reaction is found only after the incorporation of additives with MgH_(2).In depth characterization study by X-ray diffraction(XRd)technique provides convincing evidence that the CrO_(3) additive interacts with MgH_(2) and produces Cr/MgO *** free energy analyses confirm the thermodynamic feasibility of conversion from MgH_(2)/CrO_(3) to MgO/Cr,which is well supported by the identification of Cr(0)in the powder by X ray photoelectron spectroscopy(XPS)*** high resolution transmission electron microscopy(HRTEM)and energy dispersive spectroscopy(EdS)we found evidence for the presence of 5 nm size Cr nanocrystals on the surface of MgO rock salt *** is also convincing ground to consider that MgO rock salt accommodates Cr in the *** observations support the argument that creation of active metal–metal dissolved rock salt oxide interface may be vital for improving the reactivity of MgH_(2),both for the improved storage of hydrogen and lithium.

关键词： Hydrogen storage Rechargeable batteries Binary hydrides Metal oxides Catalytic mechanism.

Advanced strategies for marine antifouling based on nanomaterial-enhanced functional PdMS coatings

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Nano Materials Science 2024年第4期6卷 375-395页

作者： Xiaohui Shi Hao Wei Wenjun Zhou paul E.d.Soto Rodriguez Cunguo Lin Lei Wang Zhijia Zhang School of Materials Science and Chemical Engineering Harbin Engineering University Qingdao Innovation and development Center of Harbin Engineering University State Key Laboratory for Marin Corrosion and Protection Luoyang Ship Material Research Institute (LSMRI) Instituto de Estudios Avanzados IUdEA Departamento de Física Universidad de La Laguna C/Astrofísico Francisco Sanchez School of Chemistry and Chemical Engineering Harbin Institute of Technology

Marine biofouling seriously affects human marine exploitation and transportation activities, to which marine antifouling(AF) coatings are considered to be the most cost-effective solution. Since the mid-20th century, human beings have dedicated their efforts on developing AF coatings with long cycle and high performance, leading to a large number of non-target organisms? distortion, death and marine environmental pollution. Polydimethylsiloxane(PdMS), is considered as one of the representative environment-friendly AF materials thanks to its non-toxic, hydrophobic, low surface energy and AF properties. However, PdMS AF coatings are prone to mechanical damage, weak adhesion strength to substrate, and poor static AF effect, which seriously restrict their use in the ocean. The rapid development of various nanomaterials provides an opportunity to enhance and improve the mechanical properties and antifouling properties of PdMS coating by embedding *** on our research background and the problems faced in our laboratory, this article presents an overview of the current progress in the fields of PdMS composite coatings enhanced by different nanomaterials, with the discussion focused on the advantages and main bottlenecks currently encountered in this field. Finally, we propose an outlook, hoping to provide fundamental guidance for the development of marine AF field.

关键词： Nanomaterials Antifouling PdMS composites Environment-friendly Marine biofouling

Inpatient management of iron deficiency anemia in pediatric patients with inflammatory bowel disease: A single center experience

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World Journal of Clinical Pediatrics 2024年第1期13卷 107-117页

作者： Krishanth Manokaran Jonathan Spaan Giulio Cataldo Christopher Lyons paul d Mitchell Tatyana Sare LoriA Zimmerman paul A Rufo Center for Inflammatory Bowel disease Boston Children's HospitalBostonMA 02115United States Institutional Centers for Clinical and Translational Research Boston Children's HospitalBostonMA 02115United States

BACKGROUNd Screening for iron deficiency anemia(IdA)is important in managing pediatric patients with inflammatory bowel disease(IBd).Concerns related to adverse reactions may contribute to a reluctance to prescribe intravenous(IV)iron to treat IdA in this *** To track the efficacy and safety of IV iron therapy in treating IdA in pediatric IBd patients admitted to our *** A longitudinal observational cohort study was performed on 236 consecutive pediatric patients admitted to our tertiary IBd care center between September 2017 and december 2019.92 patients met study criteria for IdA,of which 57 received IV iron,17 received oral iron,and 18 were discharged prior to receiving iron *** Patients treated with IV iron during their hospitalization experienced a significant increase of 1.9(±0.2)g/dL in mean(±SE)hemoglobin(Hb)concentration by the first ambulatory follow-up,compared to patients who received oral iron 0.8(±0.3)g/dL or no iron 0.8(±0.3)g/dL(P=0.03).One out of 57(1.8%)patients that received IV iron therapy experienced an adverse *** Our findings demonstrate that treatment with IV iron therapy is safe and efficacious in improving Hb and iron levels in pediatric patients with IdA and active IBd.

关键词： Iron deficiency anemia Pediatric inflammatory bowel disease Intravenous iron therapy Inflammatory bowel disease

Bimetallic reduced graphene oxide/zeolitic imidazolate framework hybrid aerogels for efficient heavy metals removal

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Frontiers of Chemical Science and Engineering 2024年第8期18卷 49-66页

作者： Nurul A.Mazlan Allana lewis Fraz Saeed Butt Rajakumari Krishnamoorthi Siyu Chen Yi Huang School of Engineering Institute for Materials&ProcessesThe University of EdinburghEdinburgh EH93FBUK

Graphene oxide is a promising adsorption ***,it has been difficult to recycle and separate graphene oxide in the *** alleviate this problem,graphene oxide was thermally reduced to produce porous hydrogel which was then functionalized with *** functional groups act as not only adsorption sites but also nucleation sites for in situ crystallization of cobalt-doped zeolitic-imidazolate-framework-8 *** effects of cobalt-doping contents on the physicochemical and adsorption properties of the resulting aerogel were also evaluated by varying the cobalt *** instance,the reduced graphene oxide-polydopamine/50cobalt-zeolitic-imidazolate-framework-8 aerogel exhibited a high surface area of 900 m^(2)·g^(-1)and maintained the structure in water after ten *** as-synthesized aerogels showed an ultrahigh adsorption capacity of 1217±24.35 mg·g^(-1)with a removal efficiency of>99%of lead,as well as excellent adsorption performance toward other heavy metals,such as copper and cadmium with adsorption capacity of 1163±34.91 and 1059±31.77 mg·g^(-1),*** importantly,the lead adsorption stabilized at 1023±20.5 mg·g^(-1)with a removal efficiency of>80%after seven cycles,indicating their potential in heavy metal removal from industrial wastewater.

关键词： rGO Co-doped ZIF-8 heavy metals adsorption aerogel

Plant-available water capacity of soils at a regional scale:Analysis of fixed and dynamic field capacities

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Pedosphere 2024年第3期34卷 590-605页

作者： Vinod PHOGAT paul RPETRIE Casandra COLLINS Marcos BONAdA South Australian Research and development Institute GPO Box 397Adelaide SA 5001(Australia) School of Agriculture Food and WineWaite Research InstituteUniversity of AdelaideWaite CampusPMB1Glen Osmond SA 5064(Australia) College of Science and Engineering Flinders UniversityBedford Park SA 5042(Australia) The University of New South Wales Sydney NSW 2052(Australia) ARC Training Centre for Innovative Wine Production University of AdelaidePMB1Glen Osmond SA 5064(Australia)

Estimation of the plant-available water capacity(PAWC)of soils at a regional scale helps in adopting better land use planning,developing suitable irrigation schedules for crops,and optimizing the use of scarce water *** the current study,72 soil profiles were sampled from the Barossa region of South Australia to estimate pedo-transfer functions deduced from easily estimated soil *** functions were then used to estimate the fixed(10 and 33 kPa)and dynamic pressure head(h_(fc))water contents at field capacity(FC)for minimum drainage flux(0.01 and 0.001 cm d^(-1)),which serves as the upper boundary for plant-available water in *** estimated residual water content was corrected for subsoil constraints,especially the exchangeable sodium percentage(ESP).The results showed that the mean values of h_(fc)in sand-dominated light and medium textured soils(i.e.,sand,loamy sand,sandy loam,and loam)varied in a narrow range(15.8-18.2 kPa),whereas those in the clay-dominated heavy textured soils(i.e.,clay loam)showed a wide range(11.3-49.3 kPa).There were large differences in PAWC for dynamic FC(PAWC_(fc))and fixed FC at 10 kPa(PAWC10),33 kPa(PAWC33),and a mix of 10and 33 kPa(PAWC_(10,33))pressure heads depending on soil ***,the difference between PAWC at 10 kPa and h_(fc)(ΔPAWC_(10))was positive,whereas that between 33 kPa and h_(fc)(ΔPAWC_(33))was negative across all ***,the estimation of PAWC assuming a fixed FC at 10 and 33 kPa pressures(i.e.,PAWC_(10,33))for sandy,clay,and silty soils reduced the difference between fixed and dynamic pressure PAWCs tod by incorporating the impact of subsoil constraints,such as high ESP,which was more pronounced for clay and silty *** findings demonstrate the inherent inconsistencies between static pressure and flux-based dynamic FC estimations in *** heterogeneity,intra-texture variability,subsoil constraints,and swell

关键词： crop lower limit drained upper limit pedo-transfer function soil hydraulic parameter soil texture

Major,trace element and Sr-Nd isotope evidence for a sublithospheric mantle source for the Umkondo large igneous province

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Geoscience Frontiers 2024年第1期15卷 263-285页

作者： Ben Hayes lewis d.Ashwal Khulekani B.Khumalo Linda M.Iaccheri School of Geosciences University of the WitwatersrandJohannesburg2050South Africa

The Mesoproterozoic(1.11 Ga)Umkondo large igneous province(LIP)in southern Africa and Antarctica was emplaced in<5 Myr and is dominated by low-Ti tholeiitic doleritic-gabbroic *** is of particular interest because it ... 详细信息

The Mesoproterozoic(1.11 Ga)Umkondo large igneous province(LIP)in southern Africa and Antarctica was emplaced ind is dominated by low-Ti tholeiitic doleritic-gabbroic *** is of particular interest because it is the least studied LIP in southern Africa with both sublithospheric and lithospheric mantle sources proposed and it coincides with the early assembly of Rodinia,so it has importance in understanding the nature of magmatism and tectonics in and around the Kalahari craton during the *** this study,we compiled a large database of existing(~750)and new(~100)major and trace element data for the Umkondo province,as well as 42 new Sr-Nd isotopic measurements,to provide constraints on its magma sources and geochemical *** element compositional variations in the low-Ti tholeiites are explained by low-pressure(1 kbar)three-phase fractional crystallisation(olivine,clinopyroxene and plagioclase)of a parent magma with~10 wt.%MgO in oxidising conditions(QFM+1).Inverse models show that the low-Ti tholeiitic magmas were derived as residual melts after the crystallization of 12%-33%olivine from primary komatiitic-basaltic magmas(up to~20 wt.%MgO)in equilibrium with mantle olivine(Fo90).Low Sm/Yb and TiO2/Yb-Nb/Yb indicate that the primary magmas were derived by 2%-20%shallow(40-50 km)partial melting of spinel *** Sm/Yb is restricted to dyke swarms and may imply limited magma production from deeper(up to~70 km)garnet lherzolite-like *** low-Ti tholeiites of the Umkondo province are enriched in large ion lithophile elements(Rb-Sr-Cs-K)and depleted in high-field strength elements(Zr-Hf-Nb-Ta),indicating the involvement of crustal material and/or the subcontinental lithospheric *** is supported by covariations in Th/Nb,Nb/Yb,Nb/La and Ce/Sm with generally negativeΔ***-Nd isotopes lend support to the notion that the Umkondo magmas were derived from depleted and/or enriched sublithospheric mantle sources and subs

关键词： Umkondo large igneous province Low-Ti magma Continental tholeiites Sublithospheric mantle sources Kalahari craton Rodinia

Quasi-static and dynamic compressive behaviour of additively manufactured Menger fractal cube structures

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defence Technology（防务技术） 2024年第7期37卷 39-49页

作者： damith Mohotti dakshitha Weerasinghe Madhusha Bogahawaththa Hongxu Wang Kasun Wijesooriya paul JHazell School of Engineering and Technology UNSWCanberraACT2600Australia School of Civil Mining and Environmental EngineeringFaculty of Engineering and Information SciencesUniversity of WollongongWollongongNSWAustralia

This paper presents the first-ever investigation of Menger fractal cubes'quasi-static compression and impact *** cubes with different void ratios were 3d printed using polylactic acid(PLA)with dimensions of 40 mm×40 mm×40 *** different orders of Menger cubes with different void ratios were considered,namely M1 with a void ratio of 0.26,M2 with a void ratio of 0.45,and M3with a void ratio of ***-static Compression tests were conducted using a universal testing machine,while the drop hammer was used to observe the behaviour under impact *** fracture mechanism,energy efficiency and force-time histories were *** the structured nature of the void formation and predictability of the failure modes,the Menger geometry showed some promise compared to other alternatives,such as foams and *** the increasing void ratio,the Menger geometries show force-displacement behaviour similar to hyper-elastic materials such as rubber and *** third-order Menger cubes showed the highest energy absorption efficiency compared to the other two geometries in this *** findings of the present work reveal the possibility of using additively manufactured Menger geometries as an energy-efficient system capable of reducing the transmitting force in applications such as crash barriers.

关键词： Additive manufacturing Fractal geometries Menger cube Energy absorption Quasi-static