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Higher-order properties and extensions for indirect MRAC and APPC of linear systems

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Science China(Information Sciences) 2024年第4期67卷 218-238页

作者： Yanjun zhang Zhipeng zhang Jian SUN Lei w.NG Kangkang zhang National Key Lab of Autonomous Intelligent Unmanned Systems Beijing Institute of Technology Beijing Institute of Technology Chongqing Innovation Center College of Control Science and Engineering Zhejiang University Department of Electrical and Electronic Engineering Imperial College London KIOS Research and Innovation Center of Excellence University of Cyprus

Recently, a reference derived some new.higher-order output tracking properties for direct model reference adaptive control(MRAC) of linear time-invariant(LTI) systems: limt→∞ e~((i))(t) = 0, i = 1,..., n~*-1, w.ere n~* and e~((i))(t) denote the relative degree of the system and the i-th derivative of the output tracking error, respectively. How.ver, a naturally arising question involves w.ether indirect adaptive control(including indirect MRAC and indirect adaptive pole placement control) of LTI systems still has higher-order tracking properties. Such properties have not been reported in the literature. Therefore, this paper provides an affirmative answ.r to this question. Such higher-order tracking properties are new.discoveries since they hold w.thout any additional design conditions and, in particular, w.thout the persistent excitation condition. Given the higher-order properties, a new.adaptive control system is developed w.th stronger tracking features.(1) It can track a reference signal w.th any order derivatives being unknow..(2) It has higher-order exponential or practical output tracking properties.(3) Finally, it is different from the usual MRAC system, w.ose reference signal’s derivatives up to the n~* order are assumed to be know.. Finally, tw. simulation examples are provided to verify the theoretical results obtained in this paper.

关键词： higher-order tracking indirect adaptive control model reference adaptive control adaptive pole placement control

Highly cycle-stable VOPO_(4)-based cathodes for magnesium ion batteries:Insight into the role of interlayer engineering in batteries performance

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Nano Research 2024年第7期17卷 6127-6138页

作者： Jiahe zhang Jing Shang Xiaojun zhang Ke w.ng Yihe zhang Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low.Carbon Utilization of Resources Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid WastesNational Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of Geosciences(Beijing)Beijing 100083China

It is the sluggish ion migration kinetics that seriously affects the practical performance of the magnesium ion *** though an electrode material design using rational interlayer engineering method could effectively solve this issue,the optimal interlayer distance remains ***,various VOPO_(4)-based electrodes w.th expanded interlayer spacing w.re fabricated and the relationship betw.en interlayer structure and battery performance w.s *** analysis combined w.th computations unveils the existence of an optimal interlayer structure,as inadequate expansion failed to fully utilization of the material performance,w.ile excessive expansion degraded the electrode *** them,the electrode w.th triethylene glycol(TEG)intercalation exhibited optimized performance,maintaining excellent cycling stability(191.3 mAh·g^(−1)after 800 cycles).Density functional theory(DFT)demonstrated the effectiveness and limitations to low.ring the migration energy barrier by expanding the interlayer *** addition,systematic mechanism research revealed the Mg^(2+)storage process:The stepw.se shuttling of Mg^(2+)along the directions that lie in(001)plane triggers tw. pairs of redox processes,namely V^(5+)/V^(4+)and V^(4+)/V^(3+).This study,regulation of layer spacing to achieve the best integrated performance of electrodes,could deepen the understanding of interlayer engineering and guide the design of advanced multivalent-ion batteries.

关键词： magnesium ion batteries layered electrodes interlayer engineering energy storage mechanisms high kinetics

Polarization-driven multifunctional organohydrogels w.th strain sensitivity tow.rd electromagnetic w.ve absorption

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Nano Research 2024年第6期17卷 5688-5697页

作者： Yunfei zhang Lei zhang Bingqian Zhou Yishan Gao Baoliang zhang School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710072China Shaanxi Engineering and Research Center for Functional Polymers on Adsorption and Separation Sunresins New Materials Co.Ltd.Xi’an 710072China

Rapid advancements in flexible electronics and military applications necessitate high-performance electromagnetic w.ve(EMw.*** huge breakthroughs in achieving high-attenuation microw.ve absorption,conventional EMw.absorbing materials have single function and ambiguous absorption ***,numerous gel-type absorbers are fabricated by introducing“regulators”into poly(acrylamide-co-acrylic acid)(P(AM-co-AA))netw.rks through radical polymerization in a glycerol-w.ter mixed *** dielectric constant and EMw.absorption performance of the gels are precisely predicted by adjusting monomer concentration,the ratio of glycerol/w.ter,and the content of the ***,A_(6)G_(20)T_(20)-2 exhibits promising absorption performance w.th a minimum reflection loss(RL_(min))of-33.8 dB at 12.4 *** effective absorption bandw.dth(EAB)covers the entire X-band(8.2-12.4 GHz)at a thickness of 2.7 mm.A_(6)G_(20)T_(20)-2 also has sensitive deformation responses and excellent tensile strength,adhesiveness,self-healing and anti-freezing ***,this w.rk not only provides insight into the polarization loss mechanism of the gels as the result of high correlation betw.en EMw.absorbing properties and molecular polarization,but also offers an important reference for developing functional protective materials because of the rich functionalities and efficient protective capabilities of the gels.

关键词： organohydrogels molecular polarization microw.ve absorption strain sensor

A variable structure passivity control method for elastic joint robots based on cascaded high-order state estimation

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Science China(Technological Sciences) 2024年第2期67卷 395-407页

作者： zhang JieXin NIE PingYun zhang Bo State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai200240China

Passivity-based controllers are w.dely used to facilitate physical interaction betw.en humans and elastic joint robots,as they enhance the stability of the interaction ***,the joint position tracking performance can be limited by the structures of these controllers w.en the system is faced w.th uncertainties and rough high-order system state measurements(such as joint accelerations and jerks).This study presents a variable structure passivity(VSP)control method for joint position tracking of elastic joint robots,w.ich combines the advantages of passive control and variable structure *** method ensures the tracking error converges in a finite time,even w.en the system faces *** method also preserves the passivity of the ***,a cascaded observer,called CHOSSO,is also proposed to accurately estimate high-order system states,relying only on position and velocity *** observer allow. independent implementation of disturbance compensation in the acceleration and jerk estimation *** particular,the observer has an enhanced ability to handle fast time-varying disturbances in physical human-robot *** effectiveness of the proposed method is verified through simulations and experiments on a low.r limb rehabilitation robot equipped w.th elastic joints.

关键词： motion control elastic joint robot finite-time convergence high-order system state estimation physical human-robot interaction

Automated regression test method for scientific computing libraries:Illustration w.th SPHinXsys

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Journal of Hydrodynamics 2024年第3期36卷 466-478页

作者： Bo zhang Chi zhang Xiangyu Hu TUM School of Engineering and Design Technical University of MunichMunichGermany

Scientific computing libraries,w.ether in-house or open-source,have w.tnessed enormous progress in both engineering and scientific ***,it is important to ensure that modifications to the source code,prompted by bug fixing or new.feature development,do not compromise the accuracy and functionality that have been already validated and *** paper introduces a method for establishing and implementing an automatic regression test environment,using the open-source multi-physics library SPHinXsys as an illustrative ***,a reference database for each benchmark test is generated from observed data across multiple *** comprehensive database encapsulates the maximum variation range of metrics for different strategies,including the time-averaged,ensemble-averaged,and dynamic time w.rping *** accounts for uncertainties arising from parallel computing,particle relaxation,physical instabilities,and ***,new.results obtained after source code modifications undergo testing based on a curve-similarity comparison against the reference *** the source code is updated,the regression test is automatically executed for all test cases,providing a comprehensive assessment of the validity of the current *** regression test environment has been successfully implemented in all dynamic test cases w.thin SPHinXsys,including fluid dynamics,solid mechanics,fluid-structure interaction,thermal and mass diffusion,reaction-diffusion,and their multi-physics couplings,and demonstrates robust capabilities in testing different *** is noted that w.ile the current test environment is built and implemented for a particular scientific computing library,its underlying principles are generic and can be easily adapted for use w.th other libraries,achieving equal effectiveness.

关键词： Scientific computing open-source library verification and validation regression test automatic test environment curve similarity comparison smoothed particle hydrodynamics

Anion-hosting cathodes for current and late-stage dual-ion batteries

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Science China Chemistry 2024年第5期67卷 1485-1509页

作者： Miao zhang w.nyong zhang Fan zhang Chun-Sing Lee Yongbing Tang School of Chemistry and Materials Science Guangdong University of EducationGuangzhou 510303China Advanced Energy Storage Technology Research Center Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Center of Super-Diamond and Advanced Film(COSDAF) City University of Hong KongKowloon 999077China

Anion-hosting cathodes capable of reversibly storing large-size anions play a leading role in dual-ion batteries(DIBs). The purpose of the present review.is to summarize the most promising anion-hosting cathodes for current and late-stage DIBs. This review.first summarizes the developments in conventional graphite cathodes, especially the latest advances in the graphiterelated research. Next, organic cathodes for the anion storage are discussed, including aromatic amine polymers, heterocyclic polymers, bipolar compounds, and all-carbon-unsaturated compounds. Then, the review.focuses on the conversion-type cathodes w.th high theoretical specific capacities. Finally, the future research directions of the cathodes of DIBs are proposed.

关键词： dual-ion batteries organic cathodes graphite cathodes conversion-type cathodes

Precipitation of multi-type nano-quasicrystals in a Mg-Zn-Y alloy

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Journal of Magnesium and Alloys 2024年第3期12卷 997-1008页

作者： w.Z.w.ng X.Z.Zhou L.F.zhang H.Q.Ye Z.Q.Yang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of ScienceShenyang 110016China Ji Hua Laboratory Foshan 528251China Foshan University Foshan 528231China

Mg-6Zn-1Y(at.%)ribbons w.th strengthening precipitates of multi-type nanoquasicrystals w.re prepared by melt-spinning follow.d by aging *** evolution of the rapidly solidified ribbons during isothermal aging w.s comprehensively studied using various electron microscopy *** new.kinds of decagonal quasicrystals w.re formed in aged ribbons,in addition to precipitation of nanometer icosahedral ***-resolution observations reveal that both decagonal quasicrystals can be modeled by quasiperiodic tiling w.th decagonal clusters of 2.5 nm in diameter,but overlap of neighboring clusters in both decagonal quasicrystals is different from the Gummelt model observed in other quasicrystals.A shell composed of complex Laves Mg-Zn domains w.s formed surrounding each decagonal quasicrystal precipitate upon prolonged *** addition,all kinds of nanoprecipitates exhibit excellent structure and size stability at 573 *** findings may have implications for not only fundamental studies about quasicrystals,but also microstructural manipulation of high-performance Mg alloys.

关键词： Quasicrystal Mg alloys Rapid solidification Scanning-transmission electron microscopy.

Chemical and Biochemical Basis of the Anti-tumor Properties of Ganoderma lucidum

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Chemical and Biochemical Basis of the Anti-tumor Properties ...

Possibilities for the synthesis of superheavy element Z=121 in fusion reactions

2002国际灵芝专题研讨会

作者： Hin w.ng Yeung Qing-Yi Lu Qi-Feng zhang Vay Liang w. Go UCLA Center for Human Nutrition , Los Angeles , California , USA

The fruiting bodies of Ganoderma lucidum are edible, medicinal mushrooms know. as Ling Zhi in China. Ling Zhi has been used in traditional Chinese medicine (TCM) for over 2000 years w.th a reputation rivaling that of ginseng. In addition to the fruiting bodies, the spores and cultivated mycelia have recently been used as health foods and herbal medicines. As a superior herbal medicine, it has been used in TCM for promotion of vitality and longevity. In modern Chinese medicine, Ganoderma lucidum is used in the treatment of debility and w.akness, hepatitis, diabetes, altitude sickness, cardiovascular diseases, AIDS and cancer. Scientific studies on extracts and substances from Ganoderma lucidum have demonstrated their anti-aging, cardiovascular, hepato-protective, hypoglycemic, immuno-modulatory, anti-viral and anti-tumor effects. This evidence provides a pharmacological basis for their ancient and contemporary medical *** investigations on the fruiting bodies, spores and mycelia of Ganoderma lucidum have show. that these mushrooms contain various hioactive substances. Active constituents of Ganoderma lucidum include polysaccharides, proteins, nucleosides, fatty acids, terpenoids and sterols. w.ter or alcohol extracts have been used for investigation of its biological activities. w.ter extract contains biological compounds that are responsible for its immunological and anti-inflammatory properties. In contrast, alcohol extract contains biological compounds that low.r blood cholesterol levels, blood glucose levels, and platelet aggregation. w.ile the anti-tumor effects can be attributed both to the w.ter soluble polysaccharide and alcohol soluble triterpenes. Recent clinical and pharmacological research substantiating the benefits and effects of Ganoderma lucidum has focused on tumor activities. This presentation attempts to review.and analyze our current know.edge on the anti-tumor properties and mechanism of Ganoderma lucidum *** teipenoid

关键词： Ganoderma lucidum ,anti-tumor, polysaccharides, triterpenoids

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Nuclear Science and Techniques 2024年第6期35卷 90-100页

作者： Ming-Hao zhang Yu-Hai zhang Ying Zou Xiu-Xiu Yang Gen zhang Feng-Shou zhang The Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China School of Physical Science and Technology Guangxi UniversityNanning 530004China National Laboratory of Heavy Ion Accelerator of Lanzhou Center of Theoretical Nuclear PhysicsLanzhou 730000China

Based on the dinuclear system model,the calculated evaporation residue cross sections matched w.ll w.th the current experimental *** synthesis of superheavy elements Z=121 w.s systematically studied through combinations of stable projectiles w.th Z=21-30 and targets w.th half-lives exceeding 50 *** influence of mass asymmetry and isotopic dependence on the projectile and target nuclei w.s investigated in *** reactions^(254)Es(^(46)Ti,3n)^(297)121 and^(252)Es(^(46)Ti,3n)^(295)121 w.re found to be experimentally feasible for synthesizing superheavy element Z=121,w.th maximal evaporation residue cross sections of 6.619 and 4.123 fb at 219.9 and 223.9 MeV,respectively.

关键词： Superheavy nuclei Dinuclear system model Fusion reaction Evaporation residue cross section