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Seismic analysis of long tunnels:A review of simplified and unified methods

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Underground Space 2017年第2期2卷 73-87页

作者： Haitao Yu Yong Yuan antonio Bobet Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China State Key Laboratory for GeoMechanics and Deep Underground Engineering China University of Mining and TechnologyBeijing 100083China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China High-End Foreign Expert at Tongji University Shanghai 200092China Lyles School of Civil Engineering Purdue UniversityWest LafayetteIN 47907USA

Seismic analysis of long tunnels is important for safety evaluation of the tunnel structure during *** models of long tunnels are commonly adopted in seismic design by practitioners,in which the tunnel is usually assumed as a beam supported by the *** models can be conveniently used to obtain the overall response of the tunnel structure subjected to seismic ***,simplified methods are limited due to the assumptions that need to be made to reach the solution,*** tunnels are assembled with segments and bolts to form a lining ring and such structural details may not be included in the simplified *** most cases,the design will require a numerical method that does not have the shortcomings of the analytical solutions,as it can consider the structural details,non-linear behavior,***,long tunnels have significant length and pass through different *** of these would require large-scale seismic analysis of long tunnels with three-dimensional models,which is difficult due to the lack of available computing *** paper introduces two types of methods for seismic analysis of long tunnels,namely simplified and unified *** models,including the mass-spring-beam model,and the beam-spring model and its analytical solution are presented as examples of the simplified *** unified method is based on a multiscale framework for long tunnels,with coarse and refined finite element meshes,or with the discrete element method and the finite difference method to compute the overall seismic response of the tunnel while including detailed dynamic response at positions of potential damage or of interest.A bridging scale term is introduced in the framework so that compatibility of dynamic behavior between the macro-and meso-scale subdomains is *** are presented to demonstrate the applicability of the simplified and the unified methods.

关键词： Earthquake engineering Tunnel structure Seismic analysis Simplified method Multiscale method

Hydrological Processes and Climate Change in Hydrographic Regions of Brazil

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Journal of Water Resource and Protection 2016年第12期8卷 1103-1127页

作者： Alfredo ribeiro Neto Adriano Rolim da Paz José antonio Marengo Sin Chan Chou Civil and Environmental Engineering Department Federal University of Pernambuco Recife Brazil Civil and Environmental Engineering Department Federal University of Paraíba Joao Pessoa Brazil National Center for Monitoring and Early Warning of Natural Disasters S&#227o José dos Campos Brazil Center for Weather Forecasts and Climate Studies National Institute for Space Research Cachoeira Paulista Brazil

The objective of this work is to assess the impacts of IPCC AR5 climate change scenarios on water resources and hydrological processes across the entire Brazilian territory. Hydrological simulations are carried out in total drainage area of about 11,535,645 km2 and average stream flow of about 272,460 m3/s. The study area consists of different climates and land covers such as the Amazon Forest, Northeast Semiarid, Brazilian Savannah, Pantanal wetlands and temperate climate in the South. The atmospheric forcing to drive the large-scale hydrological model MGB-IPH is derived from the downscaling of two global climate models, HadGEM2-ES and MIROC5, by the Eta Regional Climate Model, at 20 km resolution. The Eta model provided the downscaling of the baseline (1961-1990) and three time-slices (2011-2040, 2041-2070 and 2071-2099). These projections adopted two emission scenarios, the RCP 4.5 and RCP 8.5. The change in the average and extremes of precipitation, evapotranspiration, rates of river discharge and soil moisture were assessed. The simulations showed the response of the hydrographic regions due to change of precipitation and potential evapotranspiration in the scenarios. Water availability decreases in almost the entire study area (exception for the South) and the major basins for hydroelectric power generation are affected. The Northwest, Amazon and a small area along the Northeast Atlantic coast exhibited intensification of the extremes discharges, where the anomaly is positive for high-flow (Q10) and negative for low-flow (Q95). The results highlight the most climatic sensitive regions in Brazil in terms of hydrological variables and water resources.

关键词： Hydrological Modelling IPCC Scenarios Climate Change Impacts

Rhynchophorus ferrugineus attack affects a group of compounds rather than rearranging Phoenix canariensis metabolic pathways

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Journal of Integrative Plant Biology 2016年第4期58卷 388-396页

作者： antonio Giovino Federico Martinelli Sergio Saia Consiglio per la Ricerca in Agricoltura e l'analisi dell'economia agraria(CREA) Unita di ricerca per il recupero e la valorizzazione delle Specie Floricole Mediterranee(CREA-SFM)90011 Bagheria(PA)Italy Dipartimento di Scienze Agrarie e Forestali(SAF) University of PalermoViale delle ScienzeEdif.490128 PalermoItaly Istituto Euromediterraneo di Scienza e Tecnologia(IEMEST) Via E.Amari 12390139 PalermoItaly

The red palm weevil（RPW; Rhynchophorus ferrugineus） is spreading worldwide and severely harming many palm species. However, most studies on RPW focused on insect biology, and little information is available about the plant response to the attack. In the present experiment, we used metabolomics to study the alteration of the leaf metabolome of Phoenix canariensis at initial（1^（st） stage） or advanced（2^（nd） stage）attack by RPW compared with healthy（unattacked） *** leaf metabolome significantly varied among treatments. At the 1^（st） stage of attack, plants showed a reprogramming of carbohydrate and organic acid metabolism; in contrast, peptides and lipid metabolic pathways underwent more changes during the 2^（nd） than 1^（st） stage of attack. Enrichment metabolomics analysis indicated that RPW attack mostly affected a particular group of compounds rather than rearranging plant metabolic pathways. Some compounds selectively affected during the 1^（st） rather than 2^（nd） stage（e.g. phenylalanine; tryptophan; cellobiose;xylose; quinate; xylonite; idonate; and iso-threonate; cellobiotol and arbutine） are upstream events in the phenylpropanoid,terpenoid and alkaloid biosynthesis. These compounds could be designated as potential markers of initial RPW attack. However,further investigation is needed to determine efficient early screening methods of RPW attack based on the concentrations of these molecules.

关键词： Early detection Mediterranean environment metabolomics palms plant borer

Using electricity options to hedge against financial risks of power producers

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Journal of Modern Power Systems and Clean Energy 2013年第2期1卷 101-109页

作者： Salvador PINEDA antonio J.CONEJO Center for Electric Technology Department of Electrical EngineeringTechnical University of DenmarkKgs.LyngbyDenmark University of Castilla-La Mancha Ciudad RealSpain

As a consequence of competition in electricity markets,a wide variety of financial derivatives have emerged to allow market agents to hedge against *** options and forward contracts constitute adequate instruments to manage the financial risks pertaining to price volatility or unexpected unit failures faced by power producers.A multi-stage stochastic model is described in this tutorial paper to determine the optimal forward and option contracting decisions for a risk-averse power *** key features of electricity options to reduce both price and availability risks are illustrated by using two examples.

关键词： Price risk Availability risk Stochastic programming Forward contracts Electricity options

Glial regenerative response in the imaginal discs of Drosophila melanogaster

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Neural Regeneration Research 2023年第1期18卷 109-110页

作者： Sergio B.Velarde antonio Baonza Centro de Biología Molecular“Severo Ochoa” CSIC/UAMMadridSpain

Glial cells play a key role during nervous system development and actively participate in all the cellular processes involved in maintaining its structural robustness and functional *** response to neuronal damage,glial cells proliferate,migrate to the injured region and change their morphology,function,and behavior(Gallo and Deneen,2014;Kato et al.,2018).This glial regenerative response is associated with the repairing function of these cells and is found across species,suggesting that it may reflect a common underlying genetic mechanism(Kato et al.,2018).

关键词： damage migrate

A solution to Tingley's problem for isometries between the unit spheres of compact C~*-algebras and JB~*-triples

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Science China Mathematics 2019年第3期62卷 553-568页

作者： antonio M.Peralta Ryotaro Tanaka Departamento de Ana'lisis Matem'atico Facultad de Ciencias Universidad de Granada Faculty of Mathematics Kyushu University

Let f : S(E) → S(B) be a surjective isometry between the unit spheres of two weakly compact JB*-triples not containing direct summands of rank less than or equal to 3. Suppose E has rank greater than or equal to 5. Applying techniques developed in JB*-triple theory, we prove that f admits an extension to a surjective real linear isometry T : E → B. Among the consequences, we show that every surjective isometry between the unit spheres of two compact C*-algebras A and B, without assuming any restriction on the rank of their direct summands(and in particular when A = K(H) and B = K(H′)), extends to a surjective real linear isometry from A into B. These results provide new examples of infinite-dimensional Banach spaces where Tingley's problem admits a positive answer.

关键词： Tingley’s problem extension of isometries JB*-triples compact operators

Automorphism Groups of Pseudo-real Riemann Surfaces of Low Genus

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Acta Mathematica Sinica,English Series 2014年第1期30卷 11-22页

作者： Emilio BUJALANCE antonio F.COSTA Departamento de Matemáticas Fundamentales Facultad de CienciasUNEDSenda del rey928040 MadridSpain

A pseudo-real Riemann surface admits anticonformal automorphisms but no anticonformal *** obtain the classifcation of actions and groups of automorphisms of pseudo-real Riemann surfaces of genera 2,3 and *** instance the automorphism group of a pseudo-real Riemann surface of genus 4 is eitherC4orC8or the Fro¨benius group of order 20,and in the case ofC4there are exactly two possible topological *** MK P R,g be the set of surfaces in the moduli space MK g corresponding to pseudo-real Riemann *** obtain the equisymmetric stratifcation of MK P R,g for generag=2,3,4,and as a consequence we have that MK P R,gis connected forg=2,3 but MK P R,4has three connected components.

关键词： Riemann surface automorphism anticonformal automorphism moduli space

Hyperglycemia in acute ischemic stroke: physiopathological and therapeutic complexity

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Neural Regeneration Research 2022年第2期17卷 292-299页

作者： Federica Ferrari antonio Moretti Roberto Federico Villa Department of Biology and Biotechnology Laboratory of Pharmacology and Molecular Medicine of Central Nervous SystemUniversity of PaviaVia FerrataPaviaItaly

Diabetes mellitus and associated chronic hyperglycemia enhance the risk of acute ischemic stroke and lead to worsened clinical outcome and increased mortality. However, post-stroke hyperglycemia is also present in a number of non-diabetic patients after acute ischemic stroke, presumably as a stress response. The aim of this review is to summarize the main effects of hyperglycemia when associated to ischemic injury in acute stroke patients, highlighting the clinical and neurological outcomes in these conditions and after the administration of the currently approved pharmacological treatment, i.e. insulin. The disappointing results of the clinical trials on insulin(including the hypoglycemic events) demand a change of strategy based on more focused therapies. Starting from the comprehensive evaluation of the physiopathological alterations occurring in the ischemic brain during hyperglycemic conditions, the effects of various classes of glucose-lowering drugs are reviewed, such as glucose-like peptide-1 receptor agonists, DPP-4 inhibitors and sodium glucose cotransporter 2 inhibitors, in the perspective of overcoming the up-to-date limitations and of evaluating the effectiveness of new potential therapeutic strategies.

关键词： acute ischemic stroke diabetes mellitus DPP-4 inhibitor glucose-like peptide-1 receptor agonist hyperglycemia hypoglycemia insulin physiopathology sodium glucose cotransporter 2 inhibitor

Robust and fault-tolerant spacecraft attitude control based on an extended-observer design

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Control Theory and Technology 2022年第3期20卷 323-337页

作者： Alessandro Giuseppi Francesco Delli Priscoli antonio Pietrabissa Department of Computer Control and Management EngineeringLa SapienzaUniversity of RomeVia Ariosto 25Rome00185Italy

The aim of this work is to develop a robust control strategy able to drive the attitude of a spacecraft to a reference value,despite the presence of unknown but bounded uncertainties in the system parameters and external *** to the use of an extended observer design,the proposed control law is robust against all the uncertainties that affect the high-frequency gain matrix,which is shown to capture a broad spectrum of modelling issues,some of which are often neglected by traditional *** proposed controller then provides robustness against parametric uncertainties,as moment of inertia estimation,payload deformations,actuator faults and external disturbances,while maintaining its asymptotic properties.

关键词： Extended observer Spacecraft control Attitude stabilization