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压电与声光 1988年第5期 68-71+87页

作者： c.e.lewis 钟川美·材料工程杂志社

用普通的技术,很难制备超高质量的陶瓷,而用化学法能非常好地控制陶瓷的组成、纯度和微观结构。

关键词：溶胶-凝胶法纤维微观结构孔隙凝胶铸件缺陷胶体材料制备

Guaranteed cost Attitude Tracking control for Uncertain Quadrotor Unmanned Aerial Vehicle Under Safety constraints

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Ieee/cAA Journal of Automatica Sinica 2024年第6期11卷 1447-1457页

作者： Qian Ma Peng Jin Frank L.lewis School of Automation Nanjing University of Science and TechnologyNanjing 210094China UTA Research Institute University of Texas at ArlingtonFort WorthTexas 76118 USA Ieee

In this paper,guaranteed cost attitude tracking con-trol for uncertain quadrotor unmanned aerial vehicle(QUAV)under safety constraints is ***,an augmented system is constructed by the tracking error system and reference *** transformation aims to convert the tracking control prob-lem into a stabilization control ***,control barrier function and disturbance attenuation function are designed to characterize the violations of safety constraints and tolerance of uncertain disturbances,and they are incorporated into the reward function as penalty *** on the modified reward function,the problem is simplified as the optimal regulation problem of the nominal augmented system,and a new Hamilton-Jacobi-Bellman equation is ***,critic-only rein-forcement learning algorithm with a concurrent learning tech-nique is employed to solve the Hamilton-Jacobi-Bellman equa-tion and obtain the optimal *** proposed algorithm can not only ensure the reward function within an upper bound in the presence of uncertain disturbances,but also enforce safety *** performance of the algorithm is evaluated by the numerical simulation.

关键词： Attitude tracking control quadrotor unmanned aerial vehicle(QUAV) reinforcement learning safety constraints uncertain disturbances.

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

control Policy Learning Design for Vehicle Urban Positioning via BeiDou Navigation

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Journal of Systems Science & complexity 2024年第1期37卷 114-135页

作者： QIN Yahang ZHANG chengye cHeN ci XIe Shengli lewis Frank L School of Automation Guangdong University of TechnologyGuangzhou 510006China Guangdong Key Laboratory of IoT Information Technology Guangzhou 510006China. center for Intelligent Batch Manufacturing Based on IoT Technology Key Laboratory of Intelligent Detection and The Internet of Things in Manufacturing Ministry of EducationGuangzhou 510006China Guangdong-HongKong-Macao Joint Laboratory for Smart Discrete Manufacturing Guangzhou 510006China Key Laboratory of Intelligent Information Processing and System Integration of IoT Ministry of EducationGuangzhou 510006China. UTA Research Institute The University of Texas at ArlingtonFort WorthTX 76019USA

This paper presents a learning-based control policy design for point-to-point vehicle positioning in the urban environment via BeiDou *** navigating in urban canyons,the multipath effect is a kind of interference that causes the navigation signal to drift and thus imposes severe impacts on vehicle localization due to the reflection and diffraction of the BeiDou ***,the authors formulated the navigation control system with unknown vehicle dynamics into an optimal control-seeking problem through a linear discrete-time system,and the point-to-point localization control is modeled and handled by leveraging off-policy reinforcement learning for feedback *** proposed learning-based design guarantees optimality with prescribed performance and also stabilizes the closed-loop navigation system,without the full knowledge of the vehicle *** is seen that the proposed method can withstand the impact of the multipath effect while satisfying the prescribed convergence rate.A case study demonstrates that the proposed algorithms effectively drive the vehicle to a desired setpoint under the multipath effect introduced by actual experiments of BeiDou navigation in the urban environment.

关键词： BeiDou navigation multipath effect prescribed convergence rate reinforcement learning urban localization.

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)

Performance of evolutionary optimized machine learning for modeling total organic carbon in core samples of shale gas fields

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Petroleum 2024年第1期10卷 150-164页

作者： Leonardo Goliatt c.M.Saporetti L.c.Oliveira e.Pereira Department of computational and Applied Mechanics Federal University of Juiz de Fora Department of computational Modeling Polytechnic Institute Rio de Janeiro State University Petrobras Department of Stratigraphy and Paleontology Rio de Janeiro State University

Rock samples' TOc content is the best indicator of the organic matter in source rocks. The origin rock samples' analysis is used to calculate it manually by specialists. This method requires time and resources because it relies on samples from many well intervals in source rocks. Therefore, research has been done to aid this effort. Machine learning algorithms can estimate total organic carbon instead of well logs and stratigraphic studies. In light of these efforts, the current work present a study on automating the total organic carbon estimation using machine learning approaches improved by an evolutionary methodology to give the model flexibility and precision. Genetic algorithms, differential evolution, particle swarm optimization, grey wolf optimization, artificial bee colony, and evolution strategies were used to improve machine learning models to predict TOc. The six metaheuristics were integrated into four machine learning methods: extreme learning machine, elastic net linear model, linear support vector regression, and multivariate adaptive regression splines. core samples from the YuDong-Nan shale gas field, located in the Sichuan basin, were used to evaluate the hybrid strategy. The findings show that combining machine learning models with an evolutionary algorithms in a hybrid fashion produce flexible models that accurately predict TOc. The results show that, independent of the metaheuristic used to guide the model selection, optimized extreme learning machines attained the best performance scores according to six metrics. Such hybrid models can be used in exploratory geological research,particularly for unconventional oil and gas resources.

关键词： Total organic carbon Hybrid models Automated machine learning evolutionary algorithms Geology

All-electron basis sets for H to Xe specific for ZORA calculations:Applications in atoms and molecules

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chinese Physics B 2024年第8期33卷 238-246页

作者： c.S.Gomes F.e.Jorge A.canal Neto Departamento de Fisica Universidade Federal do Espirito Santo29075-910 VitoriaESBrazil Departamento de Fisica Instituto de Ciencias Exatas e BiologicasUniversidade Federal de Ouro Preto Campus Universitario Morro do Cruzeiro35402-136 Ouro PretoMGBrazil

A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to be used in conjunction with the ZORA *** set was augmented with diffuse functions to describe electrons farther away from the nuclei *** the ZORA-ccSD(T)/QZP-ZORA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational frequencies,and atomization energies of some molecules were *** addition of core-valence corrections has been shown to improve the agreement between theoretical and experimental results for molecular *** atomization energies,a similar observation emerges when considering spin-orbit *** the augmented QZP-ZORA set,static mean dipole polarizabilities of a set of atoms were calculated and compared with previously published recommended and experimental *** evaluations of the ZORA and Douglas–Kroll–Hess Hamiltonians were made for each property studied.

关键词： QZP-ZORA and AQZP-ZORA basis sets elements from H to Xe ccSD(T)method atomic and molecular properties

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

Out-of-equilibrium Assembly Based on Host-Guest Interactions

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ccS chemistry 2024年第1期6卷 27-40页

作者： Guotai Li Reece W.lewis Rienk eelkema School of Rehabilitation Sciences and engineering University of Health and Rehabilitation SciencesQingdao 266071 Department of chemical engineering Delft University of Technology2629 HZ Delft

The field of supramolecular chemistry is rapidly progressing,transitioning from the creation of thermodynamically stable systems found in local or global minima on the free energy landscape to the development of out-of-equilibrium systems that rely on chemical reactions to establish and maintain their *** the past decade,numerous artificial out-of-equilibrium systems have been devised in various domains of supramolecular chemistry,many of which have been extensively ***,one area that has received limited attention thus far is the use of out-of-equilibrium processes to regulate host-guest *** minireview aims to address this gap by exploring the construction of out-ofequilibrium systems based on host-guest complexation,which likely employs similar strategies to those employed in analogous noncovalent *** review begins with a summary of these shared ***,it discusses representative publications that exemplify these strategies and classifies thembased onwhich component is being modulated-host,guest,or competitive *** this examination,our objective is to shed light on the design of out-of-equilibrium systems relying on host-guest interactions and provide valuable insights into the preparation strategies for various transient materials.

关键词： out-of-equilibrium host-guest chemistry self-assembly supramolecular materials chemical fuel

efficacy of nonsolvent flower pollen extracts in healthy women with urinary incontinence:A randomized,double-blind,placebo-controlled,parallel study

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current Urology 2024年第3期18卷 203-211页

作者： Marc Moulin erin D.lewis David c.crowley colleen e.May Malkanthi evans KGK Science Inc. LondonOntarioCanada Graminex L.L.C.SaginawMIUSA

Background Urinary incontinence(UI)is a debilitating and common condition that adversely affects quality of *** and surgical approaches for managing UI symptoms may result in undesirable risks and *** randomized,double-blind,placebo-controlled,parallel study investigated the efficacy of 2 nonsolvent flower pollen extracts on UI in healthy *** and methods One-hundred and fourteen women aged 40–75 years who scored≥5 on the International consultation on Incontinence Questionnaire-Urinary Incontinence Short Form(IcIQ-SF)were randomized to receive either Graminex®RcT Fem™UI,Graminex®PollenBerry®,or placebo for 24 *** primary outcome was the change in the IcIQ-SF score between the trial and placebo groups after 24 weeks of *** secondary outcomes included changes in the frequency of nocturia(recorded in 3-day void diaries)and 24-hour leakage volume(assessed via pad weight)after 6,12,18,and 24 weeks of supplementation and changes in stress-induced urinary leakage volume(after completion of a provocative maneuver challenge)after 24 weeks of *** All the groups demonstrated improvement in IcIQ-SF scores at week 24(pe RcT Fem™UI group had the greatest improvement in IcIQ-SF scores(−4.07±3.4),followed by the PollenBerry®group(−3.34±2.87)and placebo group(−2.61±3.52).The RcT Fem™UI group had corresponding improvements in 24-hour leakage volume(−17.68±39.84 g)and frequency of nocturia(−0.52±1.26)(p≤0.05).PollenBerry®supplementation significantly improved stress-induced urinary leakage volume(−7.12±15.64 g)at week *** study products demonstrated safe hematological and chemical *** RcT Fem™UI supplementation resulted in significant and clinically meaningful reductions in UI severity,with corresponding improvements in daily urinary leakage volume and frequency of ***®significantly improved stress-induced urinary leakage volume,suggesting that it may be eff

关键词： Urinary incontinence Pollen extract Healthy women Dietary supplement IcIQ-SF Urinary leakage