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Design of a Novel Exoskeleton with Passive Magnetic Spring Self-locking and Spine Lateral Balancing

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Journal of Bionic Engineering 2024年第1期21卷 236-255页

作者： Jhon F.Rodríguez-León Betsy D.M.Chaparro-rico Daniele Cafolla Francesco Lago Eduardo Castillo-Castañeda Giuseppe Carbone Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada Unidad Querétaro MecatronicaInstituto Politécnico NacionalCerro Blanco 14176090 Colinas del CimatarioQuerétaroMexico Department of Mechanical Energy and Management EngineeringUniversity of CalabriaVia P.Bucci Cubo 46 C87036 RendeItaly Faculty of Science and Engineering Department of Computer ScienceSwansea UniversitySwanseaUK CESTER University of Cluj-NapocaCluj-NapocaRomania

This paper proposes a new upper-limb exoskeleton to reduce worker physical *** proposed design is based on a novel PRRRP(P-Prismatic;R-Revolute)kinematic chain with 5 passive Degrees of Freedom(DoF).Utilizing a magnetic spring,the proposed mechanism includes a specially designed locking mechanism that maintains any desired task *** proposed exoskeleton incorporates a balancing mechanism to alleviate discomfort and spinal torsional effects also helping in limb weight *** paper reports specific models and simulations to demonstrate the feasibility and effectiveness of the proposed *** experimental characterization is performed to validate the performance of the mechanism in terms of forces and physical strain during a specific application consisting of ceiling-surface drilling *** obtained results preliminarily validate the engineering feasibility and effectiveness of the proposed exoskeleton in the intended operation task thereby requiring the user to exert significantly less force than when not wearing it.

关键词： Assistive mechanism Exoskeleton Locking mechanism Bionic robot

Clinicopathological alterations in wild mammals from the reservoir system of Trypanosoma cruzi:a scoping review

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Animal Diseases 2024年第1期4卷 48-58页

作者： Ricardo Sanchez Pérez JoséManuel Aranda-Coello JoséAntonio De Fuentes Vicente Oscar rico Chavez Facultad de Estudios Superiores Cuautitlan Universidad Nacional Autonoma deMexicoCuautitlan lzcalliEstadodeMexicoMexico El Colegio de la Frontera Sur-Unidad Campeche CampecheCampecheMexico Instituto de Ciencias Biologicas-Universidad de Ciencias y Artes de Chiapas Tuxtla GutierrezChiapasMexico Facultad de Medicina Veterinaria y Zootecnia-Universidad Nacional Autonoma deMexico Ciudad deMexicoMexico

Trypanosoma cruzi is the etiologic agent of Chagas *** flagellated protozoan is transmitted to humans as well as different species of domestic and wild animals via vectors from the Reduviidae family(known as"kissing bugs").Despite the fact that hundreds of species of wild mammals are part of the reservoir system,the morphologi-cal changes and clinical manifestations resulting from the pathogenesis of the infection have been largely *** aim of this review is to systematically compile the available information regarding clinicopathological altera-tions in wild mammals due to natural infection by *** was obtained from six online bibliographic data search platforms,resulting in the identification of 29 publications that met the inclusion *** was the most common clinical manifestation,cardiac damage was the main finding at necropsy,and lymphoplas-macytic inflammation was the most frequent microscopic ***,regardless of its role as a reservoir,*** has the potential to affect the health status of wild mammals,a situation that highlights the need for further research to analyze,measure,and compare its effects at both the individual and population levels.

关键词： Trypanosoma cruzi Chagas disease American trypanosomiasis Clinicopathological alterations Natural infection Wild mammals

Unravelling COVID-19 waves in Rio de Janeiro city:Qualitative insights from nonlinear dynamic analysis

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Infectious Disease Modelling 2024年第2期9卷 314-328页

作者： Adriane S.Reis Laurita dos Santos Américo Cunha Jr Thaís C.R.O.Konstantyner Elbert E.N.Macao Institute of Science and Technology Federal University of São PauloSão Josédos CamposSPBrazil Physics Institute University of São PauloSão PauloSPBrazil Scientific and Technological Institute Universidade BrasilSão PauloSPBrazil Department of Applied Mathematics Rio de Janeiro State UniversityRio de JaneiroRJBrazil Paulista School of Medicine Federal University of São PauloSão PauloSPBrazil

Since the COVID-19 pandemic was first reported in 2019,it has rapidly spread around the *** countries implemented several measures to try to control the virus *** healthcare system and consequently the general quality of life population in the cities have all been significantly impacted by the Coronavirus *** different waves of contagious were responsible for the increase in the number of cases that,unfortunately,many times lead to *** this paper,we aim to characterize the dynamics of the six waves of cases and deaths caused by COVID-19 in Rio de Janeiro city using techniques such as the Poincaréplot,approximate entropy,second-order difference plot,and central tendency *** results reveal that by examining the structure and patterns of the time series,using a set of non-linear techniques we can gain a better understanding of the role of multiple waves of COVID-19,also,we can identify underlying dynamics of disease spreading and extract meaningful information about the dynamical behavior of epidemiological time *** findings can help to closely approximate the dynamics of virus spread and obtain a correlation between the different stages of the disease,allowing us to identify and categorize the stages due to different virus variants that are reflected in the time series.

关键词： COVID-19 Nonlinear analysis Poincaréplot Central tendency measure

Process Design for Hybrid Sheet Metal Components

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Acta Metallurgica Sinica(English Letters) 2015年第12期28卷 1518-1524页

作者： rico Haase Roland Müller Dirk Landgrebe Peter Scholz Matthias Riemer Fraunhofer Institute for Machine Tools and Forming Technology IWU

The global trends towards improving fuel efficiency and reducing CO;emissions are the key drivers for lightweight solutions. In sheet metal processing, this can be achieved by the use of materials with a supreme strength-toweight and stiffness-to-weight ratio. Besides monolithic materials such as high-strength or light metals, in particular metal–plastic composite sheets are able to provide outstanding mechanical properties. Thus, the adaption of conventional, wellestablished forming methods for the processing of hybrid sheet metals is a current challenge for the sheet metal working industry. In this work, the planning phase for a conventional sheet metal forming process is studied aiming at the forming of metal–plastic composite sheets. The single process steps like material characterization, FE analysis, tool design and development of robust process parameters are studied in detail and adapted to the specific properties of metal–plastic composites. In material characterization, the model of the hybrid laminate needs to represent not only the mechanical properties of the individual combined materials, but also needs to reflect the behaviour of the interface zone between *** on experience, there is a strong dependency on temperature as well as strain rate. While monolithic materials show a moderate anisotropic behaviour, loads on laminates in different directions generate different strain states and completely different failure modes. During the FE analysis, thermo-mechanic and thermo-dynamic effects influence the temperature distribution within tool and work pieces and subsequently the forming behaviour. During try out and production phase,those additional influencing factors are limiting the process window even more and therefore need to be considered for the design of a robust forming process. A roadmap for sheet metal forming adjusted to metal–plastic composites is presented in this paper.

关键词： Characterization Hybrids Interface Layered structures Processing Sheet forming

To supervise or to self‑supervise:a machine learning based comparison on credit supervision

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Financial Innovation 2021年第1期7卷 562-582页

作者： JoséAmérico Pereira Antunes Central Bank of Brazil Av Presidente Vargas730Rio de Janeiro 20231‑044Brazil

This study investigates the need for credit supervision as conducted by on-site banking *** builds on a real bank on-site credit examination to compare the performance of a hypothetical self-supervision approach,in which banks themselves assess their loan portfolios without external intervention,with the on-site banking supervision approach of the Central Bank of *** experiment develops two machine learning classification models:the first model is based on good and bad ratings informed by banks,and the second model is based on past on-site credit portfolio examinations conducted by banking *** findings show that the overall performance of the on-site supervision approach is consistently higher than the performance of the self-supervision approach,justifying the need for on-site credit portfolio examination as conducted by the Central Bank.

关键词： Bank supervision Machine learning Loan loss provisions On-site credit supervision

The carbon fluxes in different successional stages:modelling the dynamics of tropical montane forests in South Ecuador

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Forest Ecosystems 2017年第2期4卷 143-153页

作者： sebastian paulick claudia dislich jürgen homeier rico fischer andreas huth Department of Ecological Modelling Helmholtz Centre for Environmental Research-UFZPermoserstr1504318 LeipzigGermany Georg-August-University Gottingen Plant EcologyUntere KarspOle 237073 GottingenGermany University of Osnabriick Institute of Environmental Systems ResearchBarbarastr1249076 OsnabruckGermany iDiv German Centre for Integrative Biodiversity Research(iDiv)Halle-Jena-LeipzigDeutscher Platz 5e04103 LeipzigGermany

Background： Tropical forests play an important role in the global carbon（C） ***, tropical montane forests have been studied less than tropical lowland forests, and their role in carbon storage is not well *** forests are highly endangered due to logging, land-use and climate *** objective was to analyse how the carbon balance changes during forest ***： In this study, we used a method to estimate local carbon balances that combined forest inventory data with process-based forest *** utilised such a forest model to study the carbon balance of a tropical montane forest in South Ecuador, comparing two topographical slope positions（ravines and lower slopes vs upper slopes and ridges）.Results： The simulation results showed that the forest acts as a carbon sink with a maximum net ecosystem exchange（NEE） of 9.3 Mg C？（ha？yr）-1during its early successional stage（0–100 years）.In the late successional stage, the simulated NEE fluctuated around zero and had a variation of 0.77 Mg C？（ha？yr）–*** simulated variability of the NEE was within the range of the field *** discovered several forest attributes（e.g., basal area or the relative amount of pioneer trees） that can serve as predictors for NEE for young forest stands（0–100 years） but not for those in the late successional stage（500–1,000 years）.In case of young forest stands these correlations are high, especially between stand basal area and ***： In this study, we used an Ecuadorian study site as an example of how to successfully link a forest model with forest inventory data, for estimating stem-diameter distributions, biomass and aboveground net primary *** conclude, this study shows that process-based forest models can be used to investigate the carbon balance of tropical montane *** this model it is possible to find hidden relationships between forest attributes and forest carbon *** relationships promote a better understandin

关键词： Forest model Tropical montane forest Forest succession Carbon balance Forest productivity FORMIND

Multi-objective Optimization of Production Scheduling Using Particle Swarm Optimization Algorithm for Hybrid Renewable Power Plants with Battery Energy Storage System

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Journal of Modern Power Systems and Clean Energy 2021年第2期9卷 285-294页

作者： Jon Martinez-rico Ekaitz Zulueta Ismael Ruiz de Argandona Unai Femandez-Gamiz Mikel Armendia The Automation and Control Unit Fundacion TeknikerBasque Research and Technology Alliance(BRTA)Ifiaki Goenaga520600 the University of the Basque Country Ing.Torres Quevedo148013 BilbaoSpain the Department of Systems Engineering and Control College of Engineering at Vitoria-GasteizUniversity of the Basque CountryNieves Cano1201006 Vitoria-GasteizSpain the Department of Nuclear and Fluid Mechanics College of Engineering at Vitoria-GasteizUniversity of the Basque CountryNieves Cano1201006 Vitoria-GasteizSpain

Considering the increasing integration of renewable energies into the power grid,batteries are expected to play a key role in the challenge of compensating the stochastic and intermittent nature of these energy ***,the deployment of batteries can increase the benefits of a renewable power *** way to increase the profits with batteries studied in this paper is performing energy *** strategy is based on storing energy at low electricity price moments and selling it when electricity price is *** this paper,a hybrid renewable energy system consisting of wind and solar power with batteries is studied,and an optimization process is conducted in order to maximize the benefits regarding the dayahead production scheduling of the plant.A multi-objective cost function is proposed,which,on the one hand,maximizes the obtained profit,and,on the other hand,reduces the loss of value of the battery.A particle swarm optimization algorithm is developed and fitted in order to solve this non-linear multi-objective *** the aim of analyzing the importance of considering both the energy efficiency of the battery and its loss of value,two more simplified cost functions are *** show the importance of including the energy efficiency in the cost function to ***,it is proven that the battery lifetime increases substantially by using the multi-objective cost function,whereas the profitability is similar to the one obtained in case the loss of value is not ***,due to the small difference in price among hours in the analyzed Iberian electricity market,it is observed that low profits can be provided to the plant by using batteries just for arbitrage purposes in the day-ahead market.

关键词： Battery energy storage system energy arbitrage hybrid renewable energy system particle swarm optimization

Zwitterionic and mesoionic liquids:Molecular aggregation in 3-methylsydnone

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Science China Chemistry 2010年第9期53卷 2063-2069页

作者： CASSEL Stéphanie rico-LATTES Isabelle LATTES Armand Laboratoire des IMRCP UMR 5623Université Paul Sabatier

Ionic liquids are green solvents with interesting properties:displaying low melting points and high boiling *** offer a new approach applicable in many ***,the presence of free ions can be a matter in some cases,*** the study of nucleophilic reactions,in electrochemistry,and in each situation where there is a competition between counter ions,as in micellization of ionic *** compounds having formal unit electrical charges of opposite sign,and the same physical properties than ionic liquids would be a nice alternative to these latter *** are two classes of chemical compounds having these characteristics:zwitterionic liquids(with no uncharged canonical representation) and mesoionic liquids(in which the negative and the positive charges are delocalized).In that last class we have chosen to work with 3-methylsydnone in order to examine,in this aprotic solvent,if it was possible to observe aggregation of surfactants in the same manner as in *** all kinds of surfactants studied(ionic,zwitterionic and mesoionic) we have been able to demonstrate the formation of direct micelles:hydrogen bonding is thus not mandatory for molecular *** of the behavior in water and in formamide showed that solvophobic interactions were qualitatively comparable but with a lower intensity.

关键词： ionic liquids zwitterionic liquids mesoionic liquids 3-methylsydnone molecular aggregation micellization solvophobicity

Descentralization and Citizens Participation

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技术经济与管理研究 2000年第5期 11-14页

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