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Journal of Rock Mechanics and Geotechnical Engineering 2018年第4期10卷 653-660页

作者： Libin Gong ana Heitor Buddhima Indraratna School of Civil Mining and Environmental Engineering University of Wollongong

Rock joints infilled with sediments can strongly influence the strength of rock mass. As infilled joints often exist under unsaturated condition, this study investigated the influence of matric suction of infill on the overall joint shear strength. A novel technique that allows direct measurement of matric suction of infill using high capacity tensiometers(HCTs) during direct shear of infilled joints under constant normal stiffness(CNS) is described. The CNS apparatus was modified to accommodate the HCT and the procedure is explained in detail. Joint specimens were simulated by gypsum plaster using threedimensional(3D) printed surface moulds, and filled with kaolin and sand mixture prepared at different water contents. Shear behaviours of both planar infilled joints and rough joints having joint roughness coefficients(JRCs) of 8-10 and 18-20 with the ratios of infill thickness to asperity height(t/a)equal to 0.5 were investigated. Matric suction shows predominantly unimodal behaviour during shearing of both planar and rough joints, which is closely associated with the variation of unloading rate and volumetric changes of the infill material. As expected, two-peak behaviour was observed for the rough joints and both peaks increased with the increase of infill matric suction. The results suggest that the contribution of matric suction of infill on the joint peak normalised shear stress is relatively independent of the joint roughness.

关键词： Infilled rock joints Matric suction High capacity tensiometer (HCT) Three-dimensional (3D) printing Normalised shear stress Unloading rate

analysis of the Most Likely Regions of Stability of an NCS and Design of the Corresponding Event-driven Controller

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International Journal of Automation and computing 2018年第1期15卷 39-51页

作者： ana Paula Batista Fabio Goncalves Jota Centre for Intelligent Energy Research Federal Centre of Technological Education of Minas Gerais Belo Horizonte Brazil Graduate Program in Electrical Engineering Federal University of Minas Gerais Belo Horizonte Brazil

In this paper, some issues related to design and analysis of real networked control systems （NCS） under the focus of the most likely region of stability are addressed. Such a system is cumbersome due to its inherent variable time delays, ranging from microseconds to hours. To show the influence of such huge variations in the control performance, a laboratory-scale luminosity system has been setup using the Internet as part of the control loop with dominant time constant in the order of milliseconds. Proportional and integral （PI） control strategies with and without explicit compensation for the time-delay variations were implemented using an event-driven controller. Using the well-known Monte Carlo method and subsequent analyses of time responses, it has been possible to identify the most likely region of stability. Some experimental results show the influence of the statistical parameters of the delays on the determination of the most likely regions of stability of the NCS and how these can be used in assessment and redesign of the control system. The experiments show that much larger delays than one sample period can be supported by real NCSs without becoming unstable.

关键词： Networked control systems real NCS delay compensation most likely regions of stability delay statistics.

Abscisic acid, a promising therapeutic molecule to prevent Alzheimer’s and neurodegenerative diseases

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Neural Regeneration Research 2020年第6期15卷 1035-1036页

作者： ana María Sánchez-Pérez Department of Medicine Universitat Jaume I

Neuroinflammatory processes induce neuronal damage and underlie the onset of neurodegenerative pathologies,including Alzheimer’s disease(AD)(Calsolaro and Edison,2016).Several conditions,ranging from emotional stress to metabolic syndrome,including traumatic brain injury,chronic infections or gut microbiota disruption can cause or aggravate ***,aging is the major factor associated with neurodegenerative diseases.

关键词： degenerative Alzheimer diseases

Effect of arsenic on tolerance mechanisms of two plant growth-promoting bacteria used as biological inoculants

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Journal of Environmental Sciences 2015年第7期27卷 203-210页

作者： ana L.Armendariz Melina A.Talano ana L.Wevar Oller María I.Medina Elizabeth Agostini Departamento de Biología Molecular FCEFQy N Universidad Nacional de Río Cuarto

Bacterial ability to colonize the rhizosphere of plants in arsenic（As） contaminated soils is highly important for symbiotic and free-living plant growth-promoting rhizobacteria（PGPR）used as inoculants, since they can contribute to enhance plant As tolerance and limit metalloid uptake by plants. The aim of this work was to study the effect of As on growth,exopolysaccharide（EPS） production, biofilm formation and motility of two strains used as soybean inoculants, Bradyrhizobium japonicum E109 and Azospirillum brasilense Az39. The metabolism of arsenate（As（V）） and arsenite（As（III）） and their removal and/or possible accumulation were also evaluated. The behavior of both bacteria under As treatment was compared and discussed in relation to their potential for colonizing plant rhizosphere with high content of the metalloid. B. japonicum E109 growth was reduced with As（III）concentration from 10 μM while A. brasilense Az39 showed a reduction of growth with As（III） from 500 μM. EPS and biofilm production increased significantly under 25 μM As（III）for both strains. Moreover, this was more notorious for Azospirillum under 500 μM As（III）,where motility was seriously affected. Both bacterial strains showed a similar ability to reduce As（V）. However, Azospirillum was able to oxidize more As（III）（around 53%） than Bradyrhizobium（17%）. In addition, both strains accumulated As in cell biomass. The behavior of Azospirillum under As treatments suggests that this strain would be able to colonize efficiently As contaminated soils. In this way, inoculation with A. brasilense Az39 would positively contribute to promoting growth of different plant species under As treatment.

关键词： Accumulation Arsenic Biofilm Colonization Exopolysaccharides Plant growth-promoting rhizobacteria

Dietary supplementation with branchedchain amino acids enhances milk production by lactating sows and the growth of suckling piglets

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Journal of Animal Science and Biotechnology 2022年第6期13卷 1857-1870页

作者： Reza Rezaei ana San Gabriel Guoyao Wu Department of Animal Science Texas A&M UniversityCollege StationTX 77843USA Ajinomoto Co. Inc1-15-1 KyobashiChuokuTokyo 104-8315Japan

Background:Under current dietary regimens,milk production by lactating sows is insufficient to sustain the maximal growth of their *** precursors of glutamate and glutamine as well as substrates and activators of protein synthesis,branched-chain amino acids(BCAAs)have great potential for enhancing milk production by ***:Thirty multiparous sows were assigned randomly into one of three groups:control(a corn-and soybean meal-based diet),the basal diet+1.535%BCAAs;and the basal diet+3.07%*** ratio(g/g)among the supplemental L-isoleucine,L-leucine and L-valine was 1.00:2.56:*** were made isonitrogenous by the addition of appropriate amounts of *** sows had free access to drinking water and their respective *** number of live-born piglets was standardized to 9 per sow at d 0 of lactation(the day of parturition).On d 3,15 and 29 of lactation,body weights and milk consumption of piglets were measured,and blood samples were obtained from sows and piglets 2 h and 1 h after feeding and nursing,***:Feed intake did not differ among the three groups of *** of asparagine,glutamate,glutamine,citrulline,arginine,proline,BCAAs,and many other amino acids were greater(P<0.05)in the plasma of BCAA-supplemented sows and their piglets than those in the control *** with the control,dietary supplementation with 1.535%and 3.07%BCAAs increased(P<0.05)concentrations of free and protein-bound BCAAs,glutamate plus glutamine,aspartate plus asparagine,and many other amino acids in milk;milk production by 14%and 21%,respectively;daily weight gains of piglets by 19%and 28%,respectively,while reducing preweaning mortality rates by 50%and 70%,***:Dietary supplementation with up to 3.07%BCAAs enhanced milk production by lactating sows,and the growth and survival of their piglets.

关键词： Branched-chain amino acids Lactation Milk synthesis Milk yield Neonatal growth Sow

Bendable tube-shaped supercapacitor based on reduced graphene oxide and Prussian blue coated carbon fiber yarns for energy storage

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Journal of Energy Chemistry 2018年第3期27卷 866-873页

作者： Mohd.Khalid ana M.B.Honorato Department of Macromolecular Science and Engineering Case Western Reserve University

Carbon fiber yarns（CFY） are promising as a new type of flexible building blocks for the construction of flexible architectures for the energy storage applications. The main hurdle with CFY is how to make them high energy and power capable by using economically and environmentally viable materials. Here,we report reduced graphene oxide（r GO） and Prussian blue（PB） coated CFY, derived from a facile electrochemical process at room temperature for supercapacitor electrodes. The PB coated CFY and r GO coated CFY electrodes exhibit the excellent gravimetric capacitance of 339 F/g and 160.2 F/g, respectively, in aqueous KCl electrolyte in three-electrode cell configuration. When we coupled these electrodes inside the flexible plastic tube and separated by the electrolyte wet filter paper in order to construct flexible architecture, the resulting device delivers excellent specific energy of 52.1 Wh/kg and 26.5 Wh/kg with offering specific power of 3100 W/kg and 14400 W/kg respectively, under a wide operating potential of1.8 V with excellent rate capability. The device shows high tolerance towards bending, and retained its efficiency to the capacitance after being bent at an angle of 360° for 200 bending cycles.

关键词： Carbon fiber yarns Bendable supercapacitor Energy density Power density

A geomechanics classification for the rating of railroad subgrade performance

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Railway Engineering Science 2022年第3期30卷 323-359页

作者： Antonio Gomes Correia ana Ramos Department of Civil Engineering ISISEUniversity of MinhoGuimara˜esPortugal

The type of subgrade of a railroad foundation is vital to the overall performance of the track *** the train speed and tonnage increase,as well as environmental changes,the evaluation and influence of subgrade are even more paramount in the railroad track structure performance.A geomechanics classification for subgrade is proposed coupling the stiffness(resilient modulus)and permanent deformation behaviour evaluated by means of repeated triaxial loading *** classification covers from fine-to coarse-grained soils,grouped by UIC and *** this achievement,we first summarize the main models for estimating resilient modulus and permanent deformation,including the evaluation of their robustness and their sensitivity to mechanical and environmental *** is followed by the procedure required to arrive at the geomechanical classification and rating,as well as a discussion of the influence of environmental *** work is the first attempt to obtain a new geomechanical classification that can be a useful tool in the evaluation and modelling of the foundation of railway structures.

关键词： Subgrade Resilient modulus Permanent deformation Geomechanical classification

Landslide risk perception and communication for disaster risk management in mountain areas of developing countries：a Mexican foretaste

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Journal of Mountain Science 2016年第12期13卷 2079-2093页

作者： Irasema ALCáNTARA-AYALA ana Rosa MORENO Institute of Geography National Autonomous University of Mexico(UNAM)Ciudad UniversitariaCoyoaedn04510Mexico CityMexico Faculty of Medicine Department of Public HealthNational Autonormous University of Mexico(UNAM)Ciudad UniversitariaCoyoacan04510Mexico CityMexico

The increasing impact of disasters at local,national,regional and global scales in recent decades has provided enough evidence to urgently direct attention towards the necessity of disaster risk reduction and management,and this requires *** without communication is barren,and to communicate the risk of disaster it is necessary to understand the perception of the people at *** particular,this paper deals with the necessity to delineate strategies of risk communication in pursuance of risk knowledge as a core of disaster risk reduction and management,especially in mountain areas of developing *** portray this issue,an analysis of landslide risk perception in terms of experience,landslide risk awareness,exposure,preparedness,and risk communication and trust was undertaken in the municipality of Teziutlán,Puebla,Mexico,an area that has been affected for several decades by episodes of mass *** of the responses to a risk perception questionnaire has offered valuable insights in terms of the information and knowledge most required by the people living in the area of interest,in order to devise a realistic and functional strategy to communicate the risk of a landslide *** includes better understanding of controlling factorsand drivers of this risk,and the establishment of potential trusted sources of risk *** considering practical matters of risk assessment and management,risk perception and communication can increase the resilience of vulnerable people,and can enhance capacity building for present and future generations.

关键词： Risk perception Risk communication Landslides Disaster risk Mountain areas

Extracting Natech Reports from Large Databases: Development of a Semi-Intelligent Natech Identification Framework

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International Journal of Disaster Risk Science 2020年第6期11卷 735-750页

作者： Xiaolong Luo ana Maria Cruz Dimitrios Tzioutzios Department of Urban Management Graduate School of EngineeringKyoto UniversityKyoto 615-8540Japan Disaster Prevention Research Institute Kyoto UniversityKyoto 611-0011Japan

Natural hazard-triggered technological accidents(Natechs)refer to accidents involving releases of hazardous materials(hazmat)triggered by natural *** economic losses,as well as human health and environmental problems are caused by *** this regard,learning from previous Natechs is critical for risk ***,due to data scarcity and high uncertainty concerning such hazards,it becomes a serious challenge for risk managers to detect Natechs from large databases,such as the National Response Center(NRC)*** the largest database of hazmat release incidents,the NRC database receives hazmat release reports from citizens in the United ***,callers often have incomplete details about the incidents they are *** results in many records having incomplete ***,it is quite difficult to identify and extract Natechs accurately and *** this study,we introduce machine learning theory into the Natech retrieving research,and a Semi-Intelligent Natech Identification Framework(SINIF)is proposed in order to solve the *** tested the suitability of two supervised machine learning algorithms,namely the Long ShortTerm Memory(LSTM)and the Convolutional Neural Network(CNN),and selected the former for the development of the *** to the results,the SINIF is efficient(a total number of 826,078 records were analyzed)and accurate(the accuracy is over 0.90),while 32,841 Natech reports between 1990 and 2017 were extracted from the NRC ***,the majority of those Natech reports(97.85%)were related to meteorological phenomena,with hurricanes(24.41%),heavy rains(19.27%),and storms(18.29%)as the main causes of these reported ***,this study suggests that risk managers can benefit immensely from SINIF in analyzing Natech data from large databases efficiently.

关键词： Data extraction method Machine learning Natechs Natural hazards NRC database

Thermal properties and high-temperature ablation of high-entropy (Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) coating on graphite substrate

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Journal of Advanced Ceramics 2024年第8期13卷 1268-1281页

作者： ana C.Feltrin Daniel Hedman Farid Akhtar Division of Materials Science Lulea University of TechnologyLulea 97187Sweden Center for Multidimensional Carbon Materials(CMCM) Institute for Basic Science(IBS)Ulsan 44919Republic of Korea

An entropy-stabilized multicomponent ultrahigh-temperature ceramic(UHTC)coating,(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2),on a graphite substrate was in-situ sintered by spark plasma sintering(SPs)from constituent transition metal diboride ***(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) coating had a hardness of 31.2±2.1 GPa and resisted 36.9 GPa of stress before delamination,as observed at the *** temperature-dependent thermal properties of the multicomponent diboride(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) were obtained by molecular dynamics(MD)simulations driven by a machine learning force field(MLFF)trained on density functional theory(DFT)*** thermal conductivity,density,heat capacity,and coefficient of thermal expansion obtained by the MD simulations were used in time-dependent thermal stress finite element model(FEM)*** low thermal conductivity(<6.52 W·m^(-1)·K^(-1))of the multicomponent diboride coupled with its similar coefficient of thermal expansion to that of graphite indicated that stresses of less than 10 GPa were generated at the interface at high temperatures,and therefore,the coating was mechanically resistant to the thermal stress induced during *** experiments at 220℃ showed that the multicomponent diboride coating was resistant to thermal stresses with no visible cracking or *** ablation mechanisms were mechanical denudation and evaporation of B_(2)O_(5) and light V-Ti oxides,which caused a decrease in the mass and thickness of the coating and resulted in mass and linear ablation rates of-0.51 mg·s^(-1) and -1.38μm·s^(-1),respectively,after 60 *** findings demonstrated the thermal and mechanical stability of multicomponent entropy-stabilized diborides as coatings for carbon materials in engineering components under extreme environments.

关键词： entropy-stabilized diborides ultrahigh temperature ceramics molecular dynamics(MD)simulations density functional theory(DFT) ablation properties