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Force Compensation Control for electro-Hydraulic servo system with Pump-Valve Compound Drive via QFT-DTOC

Chinese Journal of Mechanical engineering 2024年第2期37卷 228-246页

作者： Kaixian ba Yuan Wang Xiaolong He Chunyu Wang Bin Yu Yaliang Liu Xiangdong Kong Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Qinhuangdao 066004China school of Mechanical engineering Yanshan UniversityQinhuangdao 066004China National engineering Research Center for Local Joint of Advanced Manufacturing Technology and equipment Yanshan UniversityQinhuangdao 066004China

each joint of a hydraulic-driven legged robot adopts a highly integrated hydraulic drive unit(HDU),which features a high power-weight ***,most HDUs are throttling-valve-controlled cylinder systems,which exhibit high energy *** contrast,pump control systems offer a high ***,their response ability is *** fully utilize the advantages of pump and valve control systems,in this study,a new type of pump-valve compound drive system(PCDs)is designed,which can not only effectively reduce the energy loss,but can also ensure the response speed and response accuracy of the HDUs in robot joints to satisfy the performance requirements of ***,considering the force control requirements of energy conservation,high precision,and fast response of the robot joint HDU,a nonlinear mathematical model of the PCDs force control system is first *** addition,pressure-flow nonlinearity,friction nonlinearity,load complexity and variability,and other factors affecting the system are considered,and a novel force control method based on quantitative feedback theory(QFT)and a disturbance torque observer(DTO)is designed,which is denoted as QFT-DTOC *** method improves the control accuracy and robustness of the force control system,reduces the effect of the disturbance torque on the control performance of the servo motor,and improves the overall force control performance of the ***,experimental verification is performed using the PCDs performance test *** experimental results and quantitative data show that the QFT-DTOC proposed herein can significantly improve the force control performance of the *** relevant force control method can be used as a bottom-control method for the hydraulic servo system to provide a foundation for implementing the top-level trajectory planning of the robot.

关键词： Legged robot Pump-valve compound drive system(PCDs) Force compensation control Quantitative feedback theory(QFT) Disturbance torque observer(DTO)

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Aggregation of CeAlO_(3) inclusions in heavy ingot of a steel containing 0.007% aluminum

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Journal of Iron and steel Research International 2024年第8期31卷 1960-1972页

作者： Qiu-yue Zhou Jun-tao ba Lun Zhang Wei Chen Ying Ren Li-feng Zhang school of Metallurgical and ecological engineering University of Science and Technology BeijingBeijing 100083China school of Mechanical engineering Yanshan UniversityQinhuangdao 066004HebeiChina school of Mechanical and Materials engineering North China University of TechnologyBeijing 100144China

The distribution of inclusions at the bottom of a Ce-treated heavy steel ingot was detected and *** three-dimensional morphology and spatial distribution of CeAlOs clusters were characterized using the electrolytic extraction and Micro-CT detection.A model of inclusion collision to predict the aggregation of CeAlO_(3) inclusions in the ingot was established and validated by measured *** were mainly CeAlO_(3) and a small amount of Ce_(2)O_(2)s in the tundish after cerium *** collision and aggregation of inclusions led to the formation of large clusters in the ingot during the solidification *** slag entrainment inclusions,large CeAO_(3) clusters and small CeAlO_(3) particles were observed from the center to the edge of the ingot *** inclusions were mainly concentrated at the *** number density of inclusions larger than 200μm was 0.21 mm^(-3).The maximum diameter of CeA1O_(3) clusters was 1340μ*** the edge to the radial center and from the bottom to the top,the average diameter of inclusions gradually increased due to the longer solidification time of the ingot.

关键词： Inclusion Heavy ingot Cerium treatment Collision

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Consequences of early life stress on the structure and function of the adult mouse retina

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Neural Regeneration Research 2024年第1期19卷 150-151页

作者： Juan s.Calanni Ruth e.Rosenstein Laboratory of Retinal Neurochemistry and experimental Ophthalmology Department of Human BiochemistrySchool of Medicine/CEFyBOUniversity of Buenos Aires/CONICETBuenos AiresArgentina

early-life stress(eLs)refers to a period of environmental/social deprivation,physica l,sexual or emotional abuse,neglect,severe and/or chronic trauma in the prenatal/early postnatal stage,which is closely related to many adverse psychiatric disorders later in life,such as depressive disorder,substance abuse,dysthymia,panic,anxiety,and suicidal behavior in adulthood(Waters and Gould,2022).

关键词： stress life Gould

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Carbon dots-derived three-dimensional-ordered macroporous host with high penetrability and catalytic activity for LsBs under lean electrolyte

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Rare Metals 2024年第6期43卷 2560-2573页

作者： Jiao-Zi Duan Hua-Yu Pei Quan Yang Xue Li Xin ba Xue Yong Jun-Ling Guo si-Yu Lu Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhou 450001China Country state Center for International Cooperation On Designer Low-Carbon&environmental Materials School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China Hubei Institute of Quality supervision Inspection Wuhan 430061China Department of Chemistry University of SheffieldSheffeld S37HFUK

The practical energy density of lithium-sulfur batteries(LsBs)is seriously limited by the high electrolyte-to-sulfur ratios(e/s).The e/s can be reduced by employing hosts with easy-to-infiltrate structure that ensures the uniform distribution of a lean electrolyte and high catalytic activity that can suppress"shuttle effect"via accelerating the slow conversion of soluble poly sulfides to insoluble *** the easy-to-infiltrate structures,the three-dimensional-ordered macroporous(3doM)structure is easier to scale preparation and more suitable for the existing industrial ***,it is difficult to obtain the 3doM with(1)high penetrability due to the high viscosity of frequently-used organic polymer precursors and(2)high catalytic activity due to the low confinement effect,meaning that uniformly dispersed small-sized catalytic materials are difficult to load on ***,using carbon dots(CDs)with both organic and inorganic properties as a precursor and aggregation limiting agent,a 3doM host with high penetrability and homodispersed Ni particles of small sizes(Ni-CDs-3doM)was *** this host:(1)CDs precursor with suitable viscosity can improve the penetrability.(2)CDs can effectively inhibit the agglomeration of Ni particles.(3)Uniformly dispersed small-size Ni particles offer high-efficiency catalytic activity toward sulfur ***,the Ni-CDs-3doM/sulfur cathode exhibits high sulfur utilization and stable cycling performance even under high sulfur loading(5.5 mg·cm^(-2))and low e/s(6.5μl·mg^(-1)).This work indicates the usefulness of CDs in constructing hosts for LsBs with high energy density.

关键词： Lithium-sulfur batteries Carbon dots Catalytic action easy-to-infiltrate structure Lean electrolyte

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Why sustainable Porous Carbon should be Further explored as Radar-Absorbing Material? A Comparative study with Different Nanostructured Carbons

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Journal of Renewable Materials 2024年第10期12卷 1639-1659页

作者： Alan F.N.Boss Manuella G.C.Munhoz Gisele Amaral-Labat Rodrigo G.A.Lima leonardo I.Medeiros Nila C.F.L.Medeiros Beatriz C.s.Fonseca Flavia L.Braghiroli Guilherme F.B.Lenz e silva Department of Metallurgical and Materials engineering University of de São PauloAvenida Mello MoraesCidade UniversitáriaSão PauloSP 05508-030Brazil Coordination of Applied Research and Technological Development National Institute for Space ResearchAvenida dos AstronautasJardim da GranjaSão Josédos CamposSP 12227-010Brazil Department of exact and Technological sciences Santa Cruz State UniversityRodovia Jorge Amadokm16IlhéusBA 45662900Brazil Institut de recherche sur les forêts Universitédu Québec en Abitibi-TémiscamingueRouyn-Noranda445 Bd de l’UniversitéRouyn-NorandaQC J9X 5E4Canada

Radar Absorbing Materials(RAM)are a class of composites that can attenuate incident electromagnetic waves to avoid radar *** carbon allotropes that have the potential to be used as RAM are either carbon nano-tubes(CNTs),graphene,carbon black(CB)and ultimately,sustainable porous carbon(sPC).Here,black wattle bark waste(following tannin extraction)was used as a sustainable source to produce sPC made from biomass *** was characterized and used as aﬁller for a silicone rubber matrix to produce aﬂexible *** elec-tromagnetic performance of this composite was compared with composites made with commercial CB and CNT through reﬂection loss(RL),where-10 dB is equivalent to 90%of *** composites were evaluated in single-layer,double-layer,and as radar absorbing structures(RAs)with the aim of improving their effective absorption bandwidth(eAB)performances and a reduction in *** CNT composite presented a RL of-26.85 dB at 10.89 GHz and an eAB of 2.6 GHz with a 1.9 mm thickness,while the double-layer structures using CNT and sPC provided a RL of-19.74 dB at 10.75 GHz and an eAB of 2.51 ***,the double-layer structures are~42%cheaper than the composite using only CNT since less material is ***,the largest eAB was achieved with a RAs using sPC,reaching~2.8 GHz and a RL of-49.09 dB at 10.4 ***,sPC made of black wattle bark waste can be a competitive,alternative material for use as RAM and RAs since it is cheaper,sustainable,and suitable for daily life uses such as absorbers for anechoic chambers,sensors,and elec-tromagnetic interference shields for electronics,wallets,vehicles,and others.

关键词： Microwave absorption material tannin waste dielectric constant carbon composite reﬂectivity

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The Role of Renewable Protocatechol Acid in epoxy Coating Modification: significantly Improved Antibacterial and Adhesive Properties

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Chinese Journal of Polymer science 2024年第1期42卷 63-72,I0008页

作者： Ming-Xuan Chen Jin-Yue dai Li-Yue Zhang shuai-Peng Wang Jing-Kai Liu Yong-Gang Wu Xin-Wu ba Xiao-Qing Liu school of Chemistry and Materials science Hebei UniversityBaoding 071000China Ningbo Institute of Materials Technology and engineering Chinese Academy of SciencesNingbo 315201China Key Laboratory of Marine Materials and Related Technologies Chinese Academy of SciencesNingbo 315201China

It is of great significance to design epoxy coatings with superior antibacterial properties and high adhesive properties, as well as excellent processing, superior durability, and high transparency. However, it is still a challenge because of the common complex design and synthesis. Herein, the bio-based monomer protocatechuic acid(PCA) was used as raw material, the catechol structure with high bonding and antibacterial properties was introduced into the flexible alkane segment of ethylene glycol diglycidyl ether(eGDe) through an efficient, and green method, and it was cured with isophorone diamine(IPda) to prepare corresponding thermosets. The cured resins exhibited excellent allaround qualities, particularly in bonding and antibacterial. When 30% PCA was added to pure epoxy resin, the adhesion between substrate and coating increased from 4.40 MPa to 13.60 MPa and the antibacterial rate of coating against e. coli and s. aureus could approach 100%. All of this is due to the fact that the catechol structure present in PCA has the ability to interact with various substrates and alter the permeability of bacterial cell membranes. The architecture of this method offers a fresh approach to dealing with the issues of challenging raw material selection and complex synthesis techniques.

关键词： epoxy coatings Thermosets Catechol structure Antibacterial High adhesion

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spatial analysis of Dengue through the reproduction numbers relating to socioeconomic features:Case studies on two Brazilian urban centers

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Infectious Disease Modelling 2024年第1期9卷 142-157页

作者： Ana T.C.silva Rejane C.dorn Lívia R.Tomás leonardo B.L.santos Lacita M.skalinski suani T.R.Pinho Departamento de Física Universidade Estadual de Feira de SantanaAv.Transnordestinas/n.Novo HorizonteFeira de Santana44036-900BABrazil Instituto de Física Universidade Federal da BahiaRua Barão de Jeremoabo s/nCampus Universitário de OndinaSalvador40170-115BABrazil Centro Nacional de Monitoramento e Alertas de Desastres Naturais(CeMADeN) Estrada Dr.Altino Bondensan500São Josédos Campos12247-016SPBrazil Universidade estadual de santa Cruz Campus Soane Nazaréde AndradeRodovia Jorge AmadoKm 16SalobrinhoIlhéus45662-900BABrazil Instituto de saúde Coletiva Universidade Federal da BahiaR.Basílio da Gamas/n-CanelaSalvador40110-140BABrazil Instituto Nacional de Ciência e Tecnologia-sistemas Complexos Virtual InstitutionBrazil

The study of the propagation of infectious diseases in urban centers finds a close connection with their population's social characteristics and *** work performs a spatial analysis of dengue cases in urban centers based on the basic reproduction numbers,R0,and incidence by planning areas(PAs),as well as their correlations with the Human Development Index(HDI)and the number of *** analyzed dengue epidemics in 2002 at two Brazilian urban centers,Belo Horizonte(BH)and Rio de Janeiro(RJ),using PAs as spatial *** results reveal heterogeneous spatial scenarios for both cities,with very weak correlations between R0 and both the number of trips and the HDI;in BH,the values of R0 show a less spatial heterogeneous pattern than in *** BH,there are moderate correlations between incidence and both the number of trips and the HDI;meanwhile,they weakly correlate for ***,the absence of strong correlations between the considered measures indicates that the transmission process should be treated considering the city as a whole.

关键词： Dengue Mathematical mode lbasic reproduction number Urban mobility Urban indices

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selective butyric acid production from CO_(2)and its upgrade to butanol in microbial electrosynthesis cells

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environmental science and ecotechnology 2024年第1期17卷 119-127页

作者： Meritxell Romans-Casas Laura Feliu-Paradeda Michele Tedesco Hubertus V.M.Hamelers Lluis bañeras M.dolors balaguer sebastiàPuig Paolo Dessì Institute of the environment University of Girona.Campus MontiliviCarrer Maria Aurélia Capmany 69E-17003GironaSpain Molecular Microbial ecology Group Institute of Aquatic EcologyUniversity of GironaMaria Aurelia Capmany 4017003GironaSpain Wetsus European Centre of Excellence for Sustainable Water TechnologyOostergoweg 98911MALeeuwardenthe Netherlands

Microbial electrosynthesis(Mes)is a promising carbon utilization technology,but the low-value products(i.e.,acetate or methane)and the high electric power demand hinder its industrial *** this study,electrically efficient Mes cells with a low ohmic resistance of 15.7 mU m^(2)were operated galvanostatically in fed-batch mode,alternating periods of high CO_(2)and H2 *** promoted acetic acid and ethanol production,ultimately triggering selective(78%on a carbon basis)butyric acid production via chain *** average production rate of 14.5 g m^(-2)d^(-1)was obtained at an applied current of 1.0 or 1.5 mA cm^(-2),being Megasphaera *** key chain elongating *** a second cell with the catholyte containing the enriched community resulted in butyric acid production at the same rate as the previous cell,but the lag phase was reduced by 82%.Furthermore,interrupting the CO_(2)feeding and setting a constant pH2 of 1.7e1.8 atm in the cathode compartment triggered solventogenic butanol production at a pH below *** efficient cell design resulted in average cell voltages of 2.6e2.8 V and a remarkably low electric energy requirement of 34.6 kWhel kg1 of butyric acid produced,despite coulombic efficiencies being restricted to 45%due to the cross-over of O_(2)and H2 through the *** conclusion,this study revealed the optimal operating conditions to achieve energy-efficient butyric acid production from CO_(2)and suggested a strategy to further upgrade it to valuable butanol.

关键词： Biocathode Bioelectrochemical system Chain elongation Hydrogen partial pressure Megasphaera

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effect of Mushroom extract Hericium erinaceus on spatial Memory and Morphology of Neurons in the CA1 and CA3 Regions of the Hippocampus in Ovariectomized Rats

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Open Journal of Veterinary Medicine 2024年第7期14卷 163-179页

作者： Lucia Garcia-Delgado Mariana Monserrath Verdía-Venegas Jacinto bañuelos-Pineda esther Albarrán-Rodríguez Guillermo Nolasco-Rodriguez José Ricardo Cuellar-Pérez sergio Fausto-Guerra Manuel Rosales-Cortés Master in Behavioral sciences Institute of Neurosciences University of Guadalajara Zapopan Mexico Department of Veterinary Medicine Division of Veterinary Sciences CUCBA University of Guadalajara Zapopan Mexico Botany and Zoology Laboratory CUCBA University of Guadalajara Zapopan Mexico

Various studies indicate that low levels of estradiol negatively impact cognitive abilities. extracts from the fungus Hericium erinaceus (He) contain bioactive components that promote the proper functioning of the nervous system and potential effects on protection against neurodegenerative diseases, including dementia and motor dysfunctions. The objective was to evaluate the effects of the administration of the He mushroom extract on visuospatial memory and morphology of neurons in the CA1 and CA3 regions of the hippocampus in ovariectomized rats. 40 young Wistar rats weighing 90 ± 10 g BW were used, which were distributed into four groups of 10 animals;Control Group, non-ovariectomized and untreated rats;Group e2, ovariectomized rats treated with estradiol (2 μg/kg/body weight);Group He, ovariectomized rats treated with the extract of the fungus Hericium erinaceus (0.5 mg/kg body weight) and Group Ovx/sT, ovariectomized rats, without treatment. The animals were tested in the barnes and Open Field maze, then they were sacrificed, and their brains were obtained to perform a histological analysis of neuronal morphology in the CA1 and CA3 areas of the hippocampus. The most outstanding results showed that the Ovx/sT group recorded the longest time to arrive at the escape box and stay in the barnes maze. A correlation was observed between neuronal damage and function;in the groups that did not present satisfactory performance in the maze tests, morphological alterations were identified such as the presence of some neuronal somata with degeneration characteristics such as pyknosis, nuclear basophilia and shrinkage of the cells. Its soma, as well as a decrease in the nuclear area of CA1 and CA3 neurons. It is concluded that the fungus Hericium erinaceus exerted a neuroprotective effect on the neuronal bodies of the hippocampus, associated with better performance in the visuospatial recognition memory test.

关键词： Ovariectomized Rats Ovarian Hypofunction estradiol Hericium erinaceus barnes Circular Labyrinth Open Field Labyrinth

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Optimized CUda Implementation to Improve the Performance of Bundle Adjustment Algorithm on GPUs

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Journal of software engineering and Applications 2024年第4期17卷 172-201页

作者： Pranay R. Kommera suresh s. Muknahallipatna John e. McInroy Department of electrical engineering and Computer science University of Wyoming Laramie Wyoming USA

The 3D reconstruction pipeline uses the Bundle Adjustment algorithm to refine the camera and point parameters. The Bundle Adjustment algorithm is a compute-intensive algorithm, and many researchers have improved its performance by implementing the algorithm on GPUs. In the previous research work, “Improving Accuracy and Computational Burden of Bundle Adjustment Algorithm using GPUs,” the authors demonstrated first the Bundle Adjustment algorithmic performance improvement by reducing the mean square error using an additional radial distorting parameter and explicitly computed analytical derivatives and reducing the computational burden of the Bundle Adjustment algorithm using GPUs. The naïve implementation of the CUda code, a speedup of 10× for the largest dataset of 13,678 cameras, 4,455,747 points, and 28,975,571 projections was achieved. In this paper, we present the optimization of the Bundle Adjustment algorithm CUda code on GPUs to achieve higher speedup. We propose a new data memory layout for the parameters in the Bundle Adjustment algorithm, resulting in contiguous memory access. We demonstrate that it improves the memory throughput on the GPUs, thereby improving the overall performance. We also demonstrate an increase in the computational throughput of the algorithm by optimizing the CUda kernels to utilize the GPU resources effectively. A comparative performance study of explicitly computing an algorithm parameter versus using the Jacobians instead is presented. In the previous work, the Bundle Adjustment algorithm failed to converge for certain datasets due to several block matrices of the cameras in the augmented normal equation, resulting in rank-deficient matrices. In this work, we identify the cameras that cause rank-deficient matrices and preprocess the datasets to ensure the convergence of the ba algorithm. Our optimized CUda implementation achieves convergence of the Bundle Adjustment algorithm in around 22 seconds for the largest dataset compared

关键词： scene Reconstruction Bundle Adjustment Levenberg-Marquardt Non-Linear Least squares Memory Throughput Computational Throughput Contiguous Memory Access CUda Optimization

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