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International Journal of Mining Science and Technology 2019年第3期29卷 399-408页

作者： Shahriyar Heidarzadeh Ali Saeidi alain Rouleau Department of Applied Sciences University of Quebec at Chicoutimi

Stress-induced failure is among the most common causes of instability in Canadian deep underground *** stoping is the most widely practiced underground excavation method in these mines,and creates large stopes which are subjected to stress-induced *** probability of failure(POF)depends on many factors,of which the geometry of an open stope is especially *** this study,a methodology is proposed to assess the effect of stope geometrical parameters on the POF,using numerical *** ranges for each input parameter are defined according to previous surveys on open stope geometry in a number of Canadian underground mines.A Monte-Carlo simulation technique is combined with the finite difference code FLAC3D,to generate model realizations containing stopes with different geometrical *** probability of failure(POF)for different categories of stope geometry,is calculated by considering two modes of failure;relaxation-related gravity driven(tensile)failure and rock mass brittle *** individual and interactive effects of stope geometrical parameters on the POF,are analyzed using a general multi-level factorial ***,mathematical optimization techniques are employed to estimate the most stable stope conditions,by determining the optimal ranges for each stope’s geometrical parameter.

关键词： Stope stability Stope geometrical parameters Probability of failure General factorial design Numerical modeling Sublevel open stoping

Quantitative assessment on basin-scale hydrological services of wetlands

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Science China Earth Sciences 2020年第2期63卷 279-291页

作者： Yanfeng WU Guangxin ZHANG alain NROUSSEAU Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China University of Chinese Academy of Sciences Beijing 100049China INRS-ETE/Institut National de la Recherche Scientifique-Eau Terre Environnement Quebec G1K 9A9Canada

Despite recognizing the importance of hydrological function of wetlands, basin-scale wetlands services have rarely been investigated. The PHYSITEL/HYDROTEL modelling platform was used to quantitatively assess the impact of wetlands on quickflow and baseflow with paired simulation scenarios in Duobukuli River Basin, namely with wetlands and without *** results showed that wetlands exert significant impact on basin hydrological processes by decreasing streamflow and altering streamflow regime(magnitude, frequency, duration and time of flow events). The intensity(significant or not) of wetlands influences on quickflow had daily, monthly and annual variation. Wetlands significantly attenuated quickflow during flood season while slightly support daily, monthly and annual baseflow. The average quickflow attenuation and baseflow support of wetlands were 5.89% and 0.83%, respectively. Although the intensity and effect(mitigation or augment) of wetlands on streamflow temporally varied at daily, monthly, seasonal and annual scales, wetland overall mitigated quickflow and augment baseflow in Duobukuli River Basin. Our results could provide insights for future decision-making for rehabilitation and conservation of wetlands as well as integrated basin water resources management.

关键词： Wetlands modules Hydrological processes simulation Baseflow support Quickflow mitigation Hydrological function

ON A SECOND ORDER DISSIPATIVE ODE IN HILBERT SPACE WITH AN INTEGRABLE SOURCE TERM

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Acta Mathematica Scientia 2012年第1期32卷 155-163页

作者： alain Haraux Mohamed Ali Jendoubi UPMC Univ Paris 06 UMR 7598Laboratoire Jacques-Louis Lions CNRS UMR 7598Laboratoire Jacques-Louis Lions Facult des Sciences de Bizerte Dpartement de Mathmatiques

Asymptotic behaviour of solutions is studied for some second order equations including the model casex（t）＋γx（t）＋ ↓△φb（x（t）） = h（t） with γ 〉 0 and h ∈ L1（O, ＋∞; H）, φ being continuouly differentiable with locally Lipschitz continuous gradient and bounded from below. In particular when φ is convex, all solutions tend to minimize the potential φ as time tends to infinity and the existence of one bounded trajectory implies the weak convergence of all solutions to equilibrium points.

关键词： dissipative dynamical system asymptotic behaviour gradient system heavyball with friction

Pile end bearing capacity in rock mass using cavity expansion theory

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第5期12卷 1103-1111页

作者： Haythem Gharsallaoui Mustafa Jafari alain Holeyman Department of Civil and Environmental Engineering(GCE) Institute of MechanicsMaterials and Civil engineering(iMMC)UniversitéCatholique de Louvain(UCLouvain)Louvain-la-NeuveBelgium

Much empiricism is involved in design of rock-socketed piles in rock *** light of this,an analytical solution based on the cavity expansion theory is proposed for calculating the ultimate bearing capacity at the tip of a pile embedded in rock masses obeying the Hoek-Brown failure *** ultimate end bearing capacity is evaluated by assuming that the pressure exerted at the boundaries of a pressure bulb immediately beneath the pile tip is equal to the limit pressure required to expand a spherical *** addition,a relationship is derived to predict the pile load-settlement *** demonstrate the applicability of the presented solution,the results of this study were compared to those of 91 field tests from technical *** the limitations,it is found that the end bearing resistance computed by the present work is in good agreement with the field test results.

关键词： Hoek-Brown failure criterion Spherical cavity Limit pressure End bearing capacity

Bellman Systems with Mean Field Dependent Dynamics

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Chinese Annals of Mathematics,Series B 2018年第3期39卷 461-486页

作者： alain BENSOUSSAN Miroslav BULICEK Jens FREHSE Jindal School of Management International Center for Decision and Risk Analysis University of Texas at Dallas800 W.Campbell RdSM 30 RichardsonTX 75080-3021USA Department SEEM City University of Hong Kong Hung HomKowloonHong KongChina Mathematical Institute Faculty of Mathematics and PhysicsCharles UniversitySokolovska 83186 75 Praha 8Czech Republic Institute for Applied Mathematics Department of Applied AnalysisEndenicher Allee 6053115 BonnGermany

The authors deal with nonlinear elliptic and parabolic systems that are the Bellman like systems associated to stochastic differential games with mean field dependent dynamics. The key novelty of the paper is that they allow heavily mean field dependent dynamics. This in particular leads to a system of PDE's with critical growth,for which it is rare to have an existence and/or regularity result. In the paper,they introduce a structural assumptions that cover many cases in stochastic differential games with mean field dependent dynamics for which they are able to establish the existence of a weak solution. In addition,the authors present here a completely new method for obtaining the maximum/minimum principles for systems with critical growths,which is a starting point for further existence and also qualitative analysis.

关键词：动力学系统贝尔椭圆形非线性统一样 PDE 微分

Fulminant myocarditis in adults: a narrative review

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Journal of Geriatric Cardiology 2022年第2期19卷 137-151页

作者： Santiago Montero Darryl Abrams Enrico Ammirati Florent Huang Dirk WDonker Guillaume Hekimian Cosme García-García Antoni Bayes-Genis alain Combes Matthieu Schmidt Acute Cardiovascular Care Unit Heart InstituteHospital Germans Trias i PujolDepartament de MedicinaUniversitat Autònoma de BarcelonaCIBERCVSpain Assistance Publique-Hôpitaux de Paris Pitié-Salpêtrière HospitalMedical Intensive Care UnitParisFrance Columbia University Vagelos College of Physicians&Surgeons/NewYork-Presbyterian Hospital New YorkUSA Center for Acute Respiratory Failure Columbia University Irving Medical CenterNew YorkUSA De Gasperis Cardio Center and Transplant Center Niguarda HospitalMilanoItaly Cardiology Hôpital FochSuresnesParisFrance Intensive Care Center University Medical Center UtrechtUtrechtthe Netherlands Cardiovascular and Respiratory Physiology TechMed CenterUniversity of TwenteEnschedethe Netherlands Sorbonne Université INSERM UMRS_1166-iCANInstitute of Cardiometabolism and NutritionParisFrance

Fulminant myocarditis(FM)is an uncommon syndrome characterized by sudden and severe hemodynamic compromise secondary to acute myocardial inflammation,often presenting as profound cardiogenic shock,life-threatening ventricular arrhythmias and/or electrical *** may be refractory to conventional therapies and require mechanical circulatory support(MCS).The immune system has been recognized as playing a pivotal role in the pathophysiology of myocarditis,leading to an increased focus on immunosuppressive treatment *** data have highlighted not only the fact that FM has significantly worse outcomes than non-FM,but that prognosis and management strategies of FM are heavily dependent on histological subtype,placing greater emphasis on the role of endomyocardial biopsy in *** impact of subtype on severity and prognosis will likewise influence how aggressively the myocarditis is managed,including whether MCS is *** patients with refractory cardiogenic shock secondary to FM end up requiring MCS,with venoarterial extracorporeal membrane oxygenation demonstrating favorable survival rates,particularly when initiated prior to the development of multiorgan *** the challenges facing the field are the need to more precisely identify immunopathophysiological pathways in order to develop targeted therapies,and the need to better optimize the timing and management of MCS to minimize complications and maximize outcomes.

关键词： myocarditis initiated storm

High Order Compact Schemes in Projection Methods for Incompressible Viscous Flows

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Communications in Computational Physics 2011年第4期9卷 994-1019页

作者： Michel Fournie alain Rigal Institut de Mathematiques de Toulouse Universite de Toulouse et CNRS(UMR 5219)France

Within the projection schemes for the incompressible Navier-Stokes equations(namely"pressure-correction"method),we consider the simplest method(of order one in time)which takes into account the pressure in both steps of the splitting *** this scheme,we construct,analyze and implement a new high order compact spatial approximation on nonstaggered *** approach yields a fourth order accuracy in space with an optimal treatment of the boundary conditions(without error on the velocity)which could be extended to more general *** prove the unconditional stability of the associated Cauchy problem via von Neumann *** we carry out a normal mode analysis so as to obtain more precise results about the behavior of the numerical *** we present detailed numerical tests for the Stokes and the Navier-Stokes equations(including the driven cavity benchmark)to illustrate the theoretical results.

关键词： Incompressible Navier-Stokes fractional step method high order compact scheme boundary conditions

AUTONOMY AND CONTROL OF ADAPTIVE SYSTEMS OF SYSTEMS

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International Journal of Modeling, Simulation, and Scientific Computing 2012年第1期3卷 116-136页

作者： MHAMED ITMI alain CARDON Computer Science Information Processing and Systems Laboratory National Institute of Applied Sciences of Rouen(LITIS-INSA-Rouen)BP:8avenue de l’Universit´e 76801 St-Etienne du Rouvray CedexFrance

We propose a unified approach for systems integration and behavior regulation expressing the autonomy of Systems of Systems. For this, we precise the notion of autonomyas a transposition of the living organisms case and we develop the notion of artificial tendencies and behavioral intentions. We present a multi-agent model allowing theimplementation with a new multi-scale control.

关键词： Autonomy coactivity multi-agent systems multi-scale control proactivity

On the effectiveness of dry drainage in soil salinity control

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Science China(Technological Sciences) 2009年第11期52卷 3328-3334页

作者： VINCENT Bernard BOUARFA Sami VIDAL alain Cemagref BP 44 92163 Antony Cedex France Cemagref 361 rue Jean-Franois Breton BP 5095 34196 Montpellier Cedex 5 France

Dry drainage is thought to be a potential approach to control soil salinity. This study took the Hetao Irrigation District as an example and evaluated the effectiveness of dry drainage by using remote sensing, a conceptual model and a field experiment. Archived remote sensing images from 1973―2006 were used to delineate the temporal and spatial change of soil salinity. The conceptual water and salt balance model was used to evaluate the role of dry drainage in removing excess salt from the irrigated land. The field experiment was performed to get field validation and give more accurate estimation. The results show that dry drainage did contribute to remove excess salt from the irrigated land and succeed in controlling soil salinity in the Hetao Irrigation District. It can be taken as an alternative approach in (semi-)arid area where artificial drainage is not applicable.

关键词： soil salinity dry drainage remote sensing conceptual model field experiment

Seed wasp invasions promoted by unregulated seed trade affect vegetal and animal biodiversity

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Integrative Zoology 2012年第3期7卷 228-246页

作者： Marie-Anne AUGER-ROZENBERG alain ROQUES French National Institute for Agricultural Research(INRA) Forest Ecology(UR633)OrleansFrance

Cone and seed insects are considered the most important predators of tree seeds during the pre-dispersal phase of *** them,exotic seed chalcids in the genus Megastigmus invaded Europe as a result of the rapidly-increasing and mostly unregulated seed trade for afforestation and ornamental *** their economic impact in seed orchards,until recently,little attention was paid to the ecological impact of these *** the present study,selected case studies of alien Megastigmus *** considered to assess their specific impact on the potential of natural regeneration of native woody plants and on the native entomofauna competing for seed *** re-analyzed data from former studies that did not focus on these ecological interactions and,here,present previously unpublished *** of Douglas-fir,true cedars,true firs and wild roses were sampled all over Europe,and the relative importance of the native and invasive chalcid species was assessed as well as their specific impact on seed *** most cases,the recent arrival of alien chalcids resulted in a significant decrease in the regeneration potential of the host *** the absence of competitors,alien chalcids occupied the entire seed niche in Douglas-fir,but their impact tended to decrease after the arrival of invasive seed *** firs,alien chalcids tended to displace the native chalcids,but not in wild roses and cedars,where their damage was *** biological traits that might explain invasive success of alien chalcids are ***,no general invasive patterns seem to exist.

关键词： ecological impact invasion Megastigmus seed trade