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A Learning-based Control Framework for Fast and Accurate Manipulation of a Flexible Object

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Journal of Bionic Engineering 2024年第4期21卷 1761-1774页

作者： Junyi Wang Xiaofeng Xiong silvia Tolu stanislav N.Gorb Department of Electrical and Photonics Engineering Technical University of DenmarkAnker Engelunds Vej 101Kongens LyngbyZealand2800Denmark sDU Biorobotics Mærsk Mc-Kinney Møller InstituteUniversity of Southern Denmark(SDU)Campusvej 55Odense MFunen5230Denmark Department Functional Morphology and Biomechanics Zoological InstituteUniversity of KielAm Botanischen Garten 1–9D-24118KielSchleswig-HolsteinGermany

This paper presents a learning-based control framework for fast(3 times of others).Besides,motion tracking errors are greatly reduced to 13.29 and 22.36 of constant impedance control by the OIAC of the proposed *** ad... 详细信息

This paper presents a learning-based control framework for fast(s)and accurate manipulation of a flexible object,i.e.,whip *** framework consists of a motion planner learned or optimized by an algorithm,Online Impedance Adaptation Control(OIAC),a sim2real mechanism,and a visual feedback *** experimental results show that a soft actor-critic algorithm outperforms three Deep Reinforcement Learning(DRL),a nonlinear optimization,and a genetic algorithm in learning generalization of motion *** can greatly reduce average learning trials(tos)and maximize average rewards(to>3 times of others).Besides,motion tracking errors are greatly reduced to 13.29 and 22.36 of constant impedance control by the OIAC of the proposed *** addition,the trajectory similarity between simulated and physical whips is *** presented framework provides a new method integrating data-driven and physics-based algorithms for controlling fast and accurate arm manipulation of a flexible object.

关键词： Deep reinforcement learning Deformable object manipulation Variable impedance control sim2real Visual tracking

Corrosion Behavior of Ψ and β Quasicrystalline Al–Cu–Fe Alloy

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Acta Metallurgica sinica(English Letters) 2015年第9期28卷 1117-1122页

作者： Alvaro torres sergio serna Cristobal Patio Gerardo Rosas Facultad de Ciencias Químicas e Ingeniería P.A. Ing.Mecnica UAEM Av. Universidad 1001 Col. Chamilpa62210 Cuernavaca Mor. Mexico Centro de Investigación en Ingeniería y Ciencias Aplicadas UAEM Av. Universidad 1001 Col. Chamilpa62210 Cuernavaca Mor. Mexico Facultad de Ingeniería Universidad Autónoma del CarmenCampus Ⅲ Avenida Central S/N Esq. con Fracc. MundoMaya C.P. 24115 Ciudad del Carmen Campeche Mexico Instituto de Investigaciones Metalurgicas UMSNH Edificio U. Ciudad Universitaria Morelia Mich. 58000 Mexico

Two nanostructured A1-Cu-Fe alloys, A164Cu24Fe12 and A162.5Cu25.2Fe12.3, have been studied. Icosahedral quasicrystalline （ψ） A164CH24FeI2 and crystalline cubic （ β） ***25.2Fe12.3 cylindrical ingots were first produced using normal casting techniques. High-energy mechanical milling was then conducted to obtain β icosahedral and β intermetallic nanostructured powders. Electrochemical impedance spectroscopy, linear polarization resistance, and potentiodynamic polarization were used to investigate the electrochemical corrosion characteristics of the powders in solutions with different pH values. Current density （icorr）, polarization resistance （Rp）, and impedance modulus （121） were determined. The results showed that regardless of pH value, increasing the solution temperature enhanced the corrosion resistance of the both phases. However, the electrochemical behavior of the phase indicated that its stability depends on the submerged exposure time in neutral and alkaline environments. This behavior was related to the type of corrosion products present on the surfaces of the particles along with the diffusion and charge-transfer mechanisms of the corrosion process.

关键词： Nano-quasicrystalline AI-Cu-Fe alloy Mechanical alloying Corrosion

Late Miocene/Early Pliocene vertebrate fauna from Mallorca(Balearic Islands,Western Mediterranean):an update

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Integrative Zoology 2014年第2期9卷 183-196页

作者： Pere BOVER Juan ROFEs salvador BAILON Jordi AGUsTÍ Gloria CUENCA-BEsCÓs Enric torres Josep Antoni ALCOVER IMEDEA(CsIC-UIB) Mediterranean Institute for Advanced StudiesDepartment of Biodiversity and ConservationBalearic IslandsSpain Research Associate Division of Vertebrate Zoology/Mammalogy Department American Museum of Natural HistoryNew YorkNYUSA Department of stratigraphy and Paleontology University of the Basque CountryLeioaSpain Grupo Aragosaurus-IUCA Area of PaleontologíaEarth Sciences DepartmentUniversity of ZaragozaZaragozaSpain UMR 7209-7194 of CNRs Department of Ecology and Biodiversity ManagementNational Museum of Natural HistoryParisFrance ICREA Institut Catalàde Paleoecologia Humana i EvolucióSocial(IPHES)Universitat Rovira i VirgiliTarragonaSpain

The vertebrate fossil record from the Balearic Islands(western Mediterranean)has improved considerably over the past decade,especially in Mallorca and *** Menorca,the Pliocene terrestrial fauna was updated by the discovery and description of the large-sized leporid Nuralagus,several reptiles and an *** Mal-lorca,paleontological exploration yielded 2 deposits with a Late Miocene/Early Pliocene chronology,Calóden Rafelino(CdR)and Na Burguesa-1(NB-1).so far,4 new mammalian taxa and 2 new reptiles have been iden-tified for the CdR deposit,whereas the faunal assemblage from the recently discovered deposit(Apr 2012)of NB-1 is currently composed of,at least,6 terrestrial mammals,8 reptiles and an *** faunal composi-tion and some primitive characteristics of the obtained taxa suggest that the chronology of this deposit is slight-ly earlier than the *** terrestrial vertebrates recorded in these 2 Mallorcan deposits are changing the view of the paleofaunal assemblage previously known for the Plio-Pleistocene of the *** charac-teristics displayed by some of the taxa suggest that these faunas would be at the beginning of an isolated *** this paper we present a preliminary report on the fossils recovered from the NB-1 deposit,as well as some unpublished data from CdR,and we analyze the whole fauna from both Mallorcan deposits,focusing on taxonomical and paleobiogeographical aspects.

关键词： Early Pliocene Late Miocene Mallorca new fauna paleobiogeography

Variational Calculus With Conformable Fractional Derivatives

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IEEE/CAA Journal of Automatica sinica 2017年第2期4卷 340-352页

作者： Matheus J.Lazo Delfim F.M.torres Instituto de Matemática Estatística e Física-FURG Center for Research and Development in Mathematics and Applications (CIDMA) Department of MathematicsUniversity of Aveiro

Invariant conditions for conformable fractional problems of the calculus of variations under the presence of external forces in the dynamics are studied. Depending on the type of transformations considered, different necessary conditions of invariance are obtained. As particular cases, we prove fractional versions of Noether's symmetry theorem. Invariant conditions for fractional optimal control problems, using the Hamiltonian formalism, are also investigated. As an example of potential application in Physics, we show that with conformable derivatives it is possible to formulate an Action Principle for particles under frictional forces that is far simpler than the one obtained with classical fractional derivatives.

关键词： Conformable fractional derivative fractional calculus of variations fractional optimal control invariant variational conditions Noether’s theorem

A model-based approximate λ-policy iteration approach to online evasive path planning and the video game ***-Man

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控制理论与应用（英文版） 2011年第3期9卷 391-399页

作者： Greg FODERARO Vikram RAJU silvia FERRARI Department of Mechanical Engineering and Materials science Duke University

This paper presents a model-based approximate λ-policy iteration approach using temporal differences for optimizing paths online for a pursuit-evasion problem,where an agent must visit several target positions within a region of interest while simultaneously avoiding one or more actively pursuing *** method is relevant to applications,such as robotic path planning,mobile-sensor applications,and path *** methodology described utilizes cell decomposition to construct a decision tree and implements a temporal difference-based approximate λ-policy iteration to combine online learning with prior knowledge through modeling to achieve the objectives of minimizing the risk of being caught by an adversary and maximizing a reward associated with visiting target *** learning and frequent decision tree updates allow the algorithm to quickly adapt to unexpected movements by the adversaries or dynamic *** approach is illustrated through a modified version of the video game ***-Man,which is shown to be a benchmark example of the pursuit-evasion *** results show that the approach presented in this paper outperforms several other methods as well as most human players.

关键词： Approximate dynamic programming Reinforcement learning Path planning Pursuit evasion games

Clear cell hepatocellular carcinoma: origin,metabolic traits and fate of glycogenotic clear and ground glass cells

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Hepatobiliary & Pancreatic Diseases International 2017年第6期16卷 570-594页

作者： Peter Bannasch silvia Ribback Qin su Doris Mayer German Cancer Research Center HeidelbergGermany Institut fur Pathologie Universitatsmedizin Greifswald Greifswald Germany Cell Marque Millipore-Sigma Rocklin USA

Clear cell hepatocellular carcinoma(CCHCC)has hitherto been considered an uncommon, highly differentiated variant of hepatocellular carcinoma(HCC) with a relatively favorable prognosis. CCHCC is composed of mixtures of clear and/or acidophilic ground glass hepatocytes with excessive glycogen and/or fat and shares histology, clinical features and etiology with common HCCs. studies in animal models of chemical, hormonal and viral hepatocarcinogenesis and observations in patients with chronic liver diseases prone to develop HCC have shown that the majority of HCCs are preceded by, or associated with, focal or diffuse excessive storage of glycogen(glycogenosis) which later may be replaced by fat(lipidosis/steatosis). In ground glass cells, the glycogenosis is accompanied by proliferation of the smooth endoplasmic reticulum, which is closely related to glycogen particles and frequently harbors the hepatitis B surface antigen(HBs Ag).From the findings in animal models a sequence of changes has been established, commencing with preneoplastic glycogenotic liver lesions, often containing ground glass cells, and progressing to glycogen-poor neoplasms via various intermediate stages, including glycogenotic/lipidotic clear cell foci, clear cell hepatocellular adenomas(CCHCA) rich in glycogen and/or fat, and CCHCC. A similar process seems to take place in humans, with clear cells frequently persisting in CCHCC and steatohepatitic HCC, which presumably represent intermediate stages in the development rather than particular variants of HCC. During the progression of the preneoplastic lesions,the clear and ground glass cells transform into cells characteristic of common HCC. The sequential cellular changes are associated with metabolic aberrations, which start with an activation of the insulin signaling cascade resulting in preneoplastic hepatic glycogenosis. The molecular and metabolic changes underlying the glycogenosis/lipidosis are apparently responsible for the dramatic metabo

关键词： clear cell hepatocellular carcinoma phenotypic heterogeneity glycogenosis lipidosis preneoplastic glycogenosis progression metabolic aberrations

spleen:A new role ffoorr an old player?

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World Journal of Gastroenterology 2011年第33期17卷 3776-3784页

作者： Giovanni Tarantino silvia savastano Domenico Capone Annamaria Colao Department of Clinical and Experimental Medicine Federico Ⅱ University Medical School of NaplesVia S.Pansini 580131 NaplesItaly Department of Molecular and Clinical Endocrinology and Oncology Division of EndocrinologyFederico Ⅱ University Medical School of NaplesVia S.Pansini 580131 NaplesItaly Department of Neurosciences Unit of Clinical PharmacologyFederico Ⅱ University Medical School of Naples80131 NaplesItaly

The spleen could be considered a neglected *** date,it has been deemed an ancillary organ in portal hypertension or an organ localization in lymphoproliferative diseases,even though it has had significant attention in infectious diseases for some ***,it is thought to be central in regulating the immune system,a metabolic asset and involved in endocrine function with regard to nonalcoholic fatty liver *** main mechanisms involved in this complex network will be critically discussed in this article.

关键词： Endocrine function Immune system Metabolic asset Nonalcoholic fatty liver disease spleen

OsDMI3,a Ca^(2+)/calmodulin kinase,integrates and amplifies H_(2)O_(2) and Ca^(2+) signaling in ABA-mediated responses

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Molecular Plant 2023年第6期16卷 968-970页

作者： Miguel-Angel torres Diego Jose Berlanga Centro de Biotecnologia y Genomica de Plantas Universidad Politecnica de Madrid(UPM)-Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria(INIA/CSIC)Campus de Montegancedo UPM28223 Pozuelo de AlarconMadridSpain Departamento de Biotecnologia-Biologia Vegetal Escuela Técnica Superior de Ingenieria AgronomicaAlimentaria y de BiosistemasUPM28040 MadridSpain

Abscisic acid(ABA)is an important hormone that regulates both plant development and stress responses(Chen et al.,2020).In the absence of ABA,group A PROTEIN PHOsPHATAsE 2Cs(PP2Cs)interact with and inhibit sUCROsE-NON-FERMENTING 1-RELATED KINAsEs 2(snRK2s).When ABA is present,ABA receptor PYRABACTIN REsIsTANCE 1 and PYRABACTIN REsIsTANCE 1-LIKE PROTEINs bind to and inhibit PP2Cs,allowing phosphorylation and activation of snRK2s that,in turn,phosphorylate downstream targets,such as transcription factors,ion channels,and transporters(Figure 1).

关键词： snRK2 Figure

Diversity-oriented synthesis of blue emissive nitrogen heterocycles and their conjugation with carbon nano-onions

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Frontiers of Chemical science and Engineering 2020年第1期14卷 76-89页

作者： Viviana Maffeis Lisa Moni Daniele Di stefano silvia Giordani Renata Riva Nano Carbon Materials Istituto Italiano di Tecnologia(IIT)10144 TorinoItaly Department of Chemistry and Industrial Chemistry University of Genova16146 GenovaItaly school of Chemical sciences Dublin City UniversityDublin 9Ireland Department of Pharmacy University of Genova16147 GenovaItaly

The search for new fluorescent molecules for possible applications as functional p-electron systems and their conjugation with different nanomaterials is nowadays of paramount importance to broaden the availability of materials with different *** we present a diversity-oriented approach to heterocyclic luminophores based on a multicomponent Ugi reaction followed by a Pd-mediated cascade *** new molecules are coupled to carbon nano-onions,and hybrid systems represent the first example of blue emitters conjugated with these carbon nanoparticles.

关键词： carbon nano-onions multicomponent reactions blue emitters fluorescence isoquinolines