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Robust Disturbance Rejection Based Control with Extended-state Resonant Observer for Sway Reduction in Uncertain Tower-cranes

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International Journal of Automation and computing 2019年第6期16卷 812-827页

作者： Horacio Coral-Enriquez Santiago Pulido-Guerrero John Cortés-Romero Programa de ingeniería mecatrónica Facultad de IngenieríaUniversidad de San Buenaventura sede BogotáCra.8H No 172-20 Edif.DBBogotáOf204Colombia departamento de ingeniería eléctrica y electrónica Facultad de IngenieríaUniversidad Nacional de Colombia sede BogotáCra.30 No 45-03 Edif.453BogotáOf222Colombia

In this paper, the problem of load transportation and robust mitigation of payload oscillations in uncertain tower-cranes is addressed. This problem is tackled through a control scheme based on the philosophy of active-disturbance-rejection. Here, a general disturbance model built with two dominant components: polynomial and harmonic, is stated. Then, a disturbance observer is formulated through state-vector augmentation of the tower-crane model. Thus, better performance of estimations for system states and disturbances is achieved. The control law is then formulated to actively reject the disturbances but also to accommodate the closed-loop system dynamics even under system uncertainty. The proposed control schema is validated via experimentation using a small-scale tower-crane,and compared with other relevant active disturbance rejection control(ADRC)-based techniques. The experimental results show that the proposed control scheme is robust under parametric uncertainty of the system, and provides improved attenuation of payload oscillations even under system uncertainty.

关键词： Active disturbance rejection control(ADRC) extended state observer(ESO) tower-crane control resonant observer disturbance observer linear matrix inequality

Fabrication of paper-based devices for in vitro tissue modeling

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Bio-design and Manufacturing 2020年第3期3卷 252-265页

作者： Hongbin Li Feng Cheng Juan A.Robledo-Lara Junlong Liao Zixuan Wang yu Shrike Zhang Division of Engineering in Medicine Department of MedicineBrigham and Women’s HospitalHarvard Medical SchoolCambridgeMA 02139USA College of Light Industry and Textile Qiqihar UniversityQiqihar 161000HeilongjiangPeople’s Republic of China departamento de ingeniería mecatrónica y eléctrica Escuela de Ingeniería y CienciasTecnológico de MonterreyCP 78211 San Luis PotosíSan Luis PotosíMexico

Paper devices have recently attracted considerable attention as a class of cost-effective cell culture substrates for various biomedical *** paper biomaterial can be used to partially mimic the in vivo cell microenvironments mainly due to its natural three-dimensional *** paper-based devices provide precise control over their structures as well as cell distributions,allowing recapitulation of certain interactions between the cells and the extracellular *** features have shown great potential for the development of normal and diseased human tissue *** this review,we discuss the fabrication of paper-based devices for in vitro tissue modeling,as well as the applications of these devices toward drug screening and personalized *** is believed that paper as a biomaterial will play an essential role in the field of tissue model engineering due to its unique performances,such as good biocompatibility,eco-friendliness,cost-effectiveness,and amenability to various biodesign and manufacturing needs.

关键词： Paper-based devices In vitro Tissue modeling Disease modeling Drug screening Personalized medicine

Erosion problem in tool steel using cold box core-making process

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China Foundry 2019年第3期16卷 204-210页

作者： Eduardo Rodríguez Alberto Pérez Rafael David Mercado-Solis Velasco-Téllez Abraham Omar Jimenez Martin Flores Marco Aurelio Gonzalez Jesus Ibarra Universidad de Guadalajara Departamento de Ingeniería de Proyectos/CUCEI CONACyT México Facultad de ingeniería Mecánica y eléctrica UANL México Nemak México S.A. García México Instituto Tecnológico José Mario Molina Pasquel y Henríquez Unidad Zapopan México

This paper presents the erosion results of the AISI H13 steel impinged by resin-bonded silica sand, using a testing rig that closely simulates the real blowing conditions during industrial core-making. Steel specimens were heat treated to obtain hardness of 294, 445 and 595 HV200 (29, 45 and 55 HRC). Erosion tests were carried out at impingement angles from 20° to 90° and air drag pressures of 1.38, 2.07 and 2.76 bar (20, 30 and 40 psi). The main results are summarized as follows:(i) The harder material, the lower erosion;(ii) the maximum erosion rate is at 30°;(iii) Little difference in erosion rate at impact angle of 60° and 90° for a constant pressure tested regardless of the hardness level;(iv) As the pressure increases, so does the erosion rate, being more sensitive for low impact angles. Finally, a differential form of the general erosion equation is applied on a practical core-making case to evaluate the erosion rate of the H13 steel at 30° and 90° impingement angles.

关键词： erosion cold box core-making H13 tool steel resin coated silica sand

detection of DC series arc in more electric aircraft power system based on optical spectrometry

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High Voltage 2020年第1期5卷 24-29页

作者： Jun Jiang Mingxin Zhao Zhe Wen Chaohai Zhang Ricardo Albarracín Center for More electric Aircraft Power System Nanjing University of Aeronautics and AstronauticsNanjing 211106People's Republic of China departamento de ingeniería eléctrica ElectrónicaAutomática y Física AplicadaEscuela Técnica Superior de Ingeniería y Diseño IndustrialUniversidad Politécnica de MadridRonda de Valencia 328012 MadridSpain

Series arcing faults have been recognised as a hazardous phenomenon in the power system of more electric aircraft(MEA),especially with the increasing voltage level and power *** of the electrical method,the optical method can be used as an approach to detect arc fault with the advantages of fast response and immunity to electromagnetic *** is the basis of optical arc detection to determine the distribution spectrum range of direct current(DC)arc *** at series arc optical detection in the MEA DC system,a DC series arc test platform was established to measure the series arc *** spectrum was disassembled though empirical mode decomposition to extract characteristic wavelengths of arc light and denoised by means of wavelet decomposition and reconstruction(wavelet transformation)to reduce equipment *** resolve the baseline drift,the baseline of the arc spectrum measured was calculated and corrected based on Savitzky−*** experimental results indicate that there are several series arc characteristic spectra of the MEA DC system,including 309.3 and 324.5 nm in the ultraviolet ***,the arc spectrum with different metals,copper and aluminium,were contrasted,indicating the arc spectral behaviour is related to the melting/boiling point and chemical properties of the anode *** measurement of the series arc spectrum makes it more effective to apply optical detection in the MEA discharging faults diagnosis.

关键词： power system series

Dynamics of mediterranean pine forests reforested after fires

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Journal of Forestry Research 2023年第2期34卷 345-354页

作者： Álvaro Enríquez-de-Salamanca departamento de Biodiversidad Ecología y EvoluciónFacultad de Ciencias BiológicasUniversidad Complutense de MadridMadridSpain Draba ingeniería y Consultoría Medioambiental San Lorenzo de El EscorialSpain

Forest fires are frequent under a Mediterranean climate and have shaped the landscape of the region but are currently altered by human action and climate *** have historically conditioned the presence of pine forests,depending on severity and forest *** of Mediterranean pine forests is not always successful,and a transition to shrublands or stands of resprouting species can occur,even after *** study analyses vegetation changes in two Mediterranean pine forests after severe fires and both *** pines had difficulty to regenerate,even despite post-fire *** problem is the difficulty of young seedlings to survive,possibly due to increased summer *** are greater in pine species at the limit of their ecological tolerance:Pinus pinea had a much better recovery success while *** and *** virtually *** pinaster had intermediate results but recovery was generally poor.A transition has taken place in many burnt areas to scrubland or to thickets of the resprouting Quercus rotundifolia,although it is not possible to know whether they will evolve into forests or remain in a sub climatic *** species may increase fire severity but facilitates post-fire ***-fire recovery difficulties are closely linked to issues of natural *** could initiate the disappearance of pine forests,but even in the absence of fire they may disappear in the long-term due to the lack of *** is needed to increase the resilience of these forests,ensuring natural regeneration,and incorporating resprouting species in the understorey.

关键词： Mediterranean region Pine forests Post-fi re recovery Vegetation dynamics Wildfi re transitions

Temporal decay of the catalytic oxidation of methane over palladium supported on silica

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Science China Chemistry 2013年第11期56卷 1601-1607页

作者： CORTS Joaquín VALENCIA eliana PINEDA Marcelo ARAyA Paulo departamento de ingeniería Química y Biotecnología Universidad de Chile departamento de Ciencia de Materiales Universidad de Chile

The temporal decay of the oxidation of methane(CH4-O2reaction)over palladium supported on silica is determined experimentally at different temperatures,comparing the results with those of various classical models which show the behavior of the adsorbed phase as the cause of the *** effect is visualized through Monte Carlo simulations of the CH4-O2reaction on a mixed lattice whose partial poisoning,due to the configuration of the OH groups on the surface of the adsorbate,is translated into a gradual decay of the reaction’s activity.

关键词： catalytic CH4-O2 reaction surface heterogeneity in superficial reaction Monte Carlo simulation superficial catalyticreaction CH4-O2 reaction over palladium

Power Grounding Optimization

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American Journal of Computational Mathematics 2015年第3期5卷 243-252页

作者： Eduardo A. Cano-Plata Oscar J. Soto-Marín Guillermo Jiménez-Lozano Jorge H. Estrada-Estrada departamento de ingenierí a elé ctrica Electr&oacute nica y Computació n Universidad Nacional de Colombia Manizales Colombia

In this paper we discuss the finite element models (FEM) using electromagnetic theory—Maxwell’s equations. Next we developed a new procedure for optimization with the idea to be implemented in the standard IEEE-80 (... 详细信息

关键词： Finite element Method Grounding Systems Circuit Model ETAP Model Engineering design

Palm oil biodiesel:An assessment of PAH emissions,oxidative potential and ecotoxicity of particulate matter

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Journal of Environmental Sciences 2021年第3期33卷 326-338页

作者： Silvana Arias Francisco Molina John R.Agudelo Grupo de Investigación en Gestión y Modelación Ambiental-GAIA Escuela AmbientalFacultad de IngenieríaUniversidad de Antioquia UdeACalle 70 No.52-21MedellínColombia departamento de ingeniería Mecánica Universidad de Antioquia UdeA

This work assessed the impact of fuelling an automotive engine with palm biodiesel(pure,and two blends of 10%and 20%with diesel,B100,B10 and B20,respectively)operating under representative urban driving conditions on 17 priority polycyclic aromatic hydrocarbon(PAH)compounds,oxidative potential of ascorbic acid(OP^(AA)),and ecotoxicity through D aphnia pulex mortality *** diluted with filtered fresh air(WD)gathered in a minitunel,and particulate matter(PM)collected directly from the exhaust gas stream(W/oD)were used for *** showed that PM collecting method significantly impact PAH *** all PAH appeared in both,WD and W/oD,higher concentrations were obtained in the last *** biodiesel concentration in the fuel blend decreased all PAH compounds,and those with 3 and 5 aromatic rings were the most *** biodiesel affected both OP^(AA)and *** B10 and B20 exhibited the same rate of ascorbic acid(AA)depletion,B100 showed significant faster oxidation rate during the first four minutes and oxidized 10%more AA at the end of the test.B100 and B20 were significantly more ecotoxic than *** lethal concentration LC50 for B10 was 6.13 mg/*** was concluded that palm biodiesel decreased PAH compounds,but increased the oxidative potential and ecotoxicity.

关键词： Biodiesel Particulate matter P emissions Oxidative stress Ecotoxicity Daphnia pulex

Biomaterials and additive manufacturing:osteochondral scaffold innovation applied to osteoarthritis(BAMOS project)

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2018年第4期19卷 329-330页

作者： Mario MONZóN departamento de ingeniería Mecánica Universidad de Las Palmas de Gran CanariaEdificio de Fabricación Integrada

Osteoarthritis(OA)is a degenerative joint disease,typified by a loss of quality of cartilage and changes in bone at the interface of a joint,resulting in pain,stiffness,and reduced mobility."According to the World Hea... 详细信息

关键词：骨关节炎添加剂 ma 革新支架工程活动性疾病