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Accelerating GW calculations through machine-learned dielectric matrices

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npj Computational Materials 2023年第1期9卷 437-445页

作者： mario G.Zauchner Andrew Horsfield Johannes Lischner Department of Materials Thomas Young CentreImperial College LondonSouth Kensington CampusLondon SW72AZUK

The GW approach produces highly accurate quasiparticle energies,but its application to large systems is computationally challenging due to the difficulty in computing the inverse dielectric *** address this challenge,we develop a machine learning approach to efficiently predict density–density response functions(DDRF)in *** atomic decomposition of the DDRF is introduced,as well as the neighborhood density–matrix descriptor,both of which transform in the same way under *** resulting DDRFs are then used to evaluate quasiparticle energies via the GW *** assess the accuracy of this method,we apply it to hydrogenated silicon clusters and find that it reliably reproduces HOMO–LUMO gaps and quasiparticle energy *** accuracy of the predictions deteriorates when the approach is applied to larger clusters than those in the training *** advances pave the way for GW calculations of complex systems,such as disordered materials,liquids,interfaces,and nanoparticles.

关键词： materials dielectric quasi

Fast Solvers of Fredholm Optimal Control Problems

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Numerical Mathematics(Theory,Methods and Applications) 2010年第4期3卷 431-448页

作者： mario Annunziato Alfio Borzi Universita degli Studi di Salerno Dipartimento di Matematica e InformaticaVia Ponte Don Melillo84084 Fisciano(SA)Italia Universita degli Studi del Sannio Dipartimento e Facolta di IngegneriaPalazzo Dell'Aquila Bosco LucarelliCorso Garibaldi 10782100 BeneventoItalia Institutfr Mathematik und Wissenschaftliches Rechnen Karl-Franzens-Universitt GrazHeinrichstr.368010 GrazAustria.

The formulation of optimal control problems governed by Fredholm integral equations of second kind and an efficient computational framework for solving these control problems is presented. Existence and uniqueness of optimal solutions is proved.A collective Gauss-Seidel scheme and a multigrid scheme are discussed. Optimal computational performance of these iterative schemes is proved by local Fourier analysis and demonstrated by results of numerical experiments.

关键词： Control Problems control problems Fredholm integral equations Existence and uniqueness optimal solutions Fourier analysis performance framework results kind

Simulation of temperature distribution and discharge crater of SiC_(p)/Al composites in a single-pulsed arc discharge

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Chinese Journal of Aeronautics 2021年第9期34卷 37-46页

作者： Jipeng CHEN Lin GU Wansheng ZHAO mario GUAGLIANO School of Mechanical and Electronic Engineering Nanjing Forestry UniversityNanjing 210037China State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Mechanical Engineering Politecnico Di MilanoPiazza Leonardo da Vinci32Italy

SiC_(p)/Al composites are difficult-to-cut *** recent years,electrical arc discharge machining has been developed to improve the machinability of these ***,there is a big challenge to build a satisfactory heat transfer model of SiC_(p)/Al composites in the arc *** is not only because of the material property difference between the reinforcement and matrix material but also because of the micro-dimension Si C *** paper established a new heat conduction simulation model considering the Si C particle-Al matrix interface and the phase change effects in a single-pulsed arc discharge of SiC_(p)/Al composites.A novel Si C particle-Al matrix cell geometric model was designed ***,the temperature distribution at a different depth from the workpiece surface was analyzed,the influence of sic volume fraction on temperature field was studied,and the contribution of the interface thermal resistance and latent heat were *** demonstrate the validity of the new numerical model,comparisons and verifications were ***,the method of improving the model was proposed and the machining mechanism of arc discharge of SiC_(p)/Al matrix materials was *** was found that high temperature is prone to concentrate on the surface layers of the workpiece especially when the Si C fraction is high,also,the temperature fluctuates respectively at the evaporation point of aluminum and Si C,and the Si C-Al resistance has less influence on temperature distribution compared to latent heat,*** model build in this work improves the simulation accuracy observably compared to the previous model,and the simulation work will help to acquire a detailed mechanism of material removal of SiC_(p)/Al composites in the arc discharge machining.

关键词： Arc discharge Discharge crater SiC_(p)/Al composites Single-pulsed Temperature distribution

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海事能源转型:未来燃料和未来排放

哈尔滨工程大学学报（英文版） 2023年第4期22卷 681-692页

作者： William Ramsay Erik Fridell mario Michan Daphne Technology SA Chemin de la Venoge 7 CH-1025 Saint-Sulpice Switzerland IVL Swedish Environmental Research Institute Valhallavägen 8111428 Stockholm Sweden

The lifecycle greenhouse gas(GHG)emissions(Well-to-Wake)from maritime transport must be reduced by at least 50%in absolute values by 2050 to contribute to the ambitions of the Paris Agreement(2015).A transition from conventional fuels to alternative fuels with zero or lower GHG emissions is viewed as the most promising avenue to reach the GHG *** GHG and toxic pollutants emitted from the use of fossil fuels(heavy fuel oil(HFO)and marine gas/diesel oil(MGO/MDO))are generally well understood,the emissions associated with the new fuel options are only now being measured and *** review provides an outlook on fuels that could help shipping respond to the decarbonization effort including Liquefied Petroleum Gas(LPG),Liquefied Natural Gas(LNG),methanol,ammonia,and hydrogen.A quantification of the pollutants associated from the use of these fuels is provided and challenges and barriers to their uptake are discussed.

关键词： Greenhouse gas Emissions Maritime transport Future fuels Future emissions Life-cycle assessment Energy transition

Artificial Neural Network(ANN)Approach for Predicting Concrete Compressive Strength by SonReb

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Structural Durability & Health Monitoring 2021年第2期15卷 125-137页

作者： mario Bonagura Lucio Nobile LADS Laboratory University of BolognaVia dell’Università50Cesena47521Italy

The compressive strength of concrete is one of most important mechanical parameters in the performance assessment of existing reinforced concrete *** to various international codes,core samples are drilled and tested to obtain the concrete compressive ***-destructive testing is an important alternative when destructive testing is not feasible without damaging the *** commonly used non-destructive testing(NDT)methods to estimate the in-situ values include the Rebound hammer test and the Ultrasonic Pulse Velocity *** poor reliability of these tests due to different aspects could be partially contrasted by using both methods together,as *** the SonReb *** are three techniques that are commonly used to predict the compressive strength of concrete based on the SonReb measurements:computational modeling,artificial intelligence,and parametric multi-variable regression *** a previous study the accuracy of the correlation formulas deduced from the last technique has been investigated in comparison with the effective compressive strengths based on destructive test results on core drilled in adjacent *** aim of this study is to verify the accuracy of Artificial Neural Approach comparing the estimated compressive strengths based on NDT measured parameters with the same effective compressive *** comparisons show the best performance of ANN approach.

关键词： Compressive concrete strength destructive tests non-destructive test ultrasonic pulse velocity rebound index SonReb method artificial neural network approach

THE AHP:A MULTICRITERIA DECISION MAKING METHODOLOGY FOR SHIFTWORK PRIORITIZING

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Journal of Systems Science and Systems Engineering 2006年第2期15卷 189-200页

作者： Claudio GARUTI mario SANDOVAL FULCRUM Engineering Ltd.A Decision Making Engineering Firm

The objective of this paper is to show that the Analytic Hierarchy Process （AHP） is a very powerful methodology for designing shiftwork schedules. Manufacturing, mining and other large industrial operations often run around the clock and their employees report for work in shifts. The huge number of variables and the amount of knowledge that needs to be structured, integrated and synthesized forces the need for a system analysis process that is able to deal with such complexity. Work flexibility is a very important issue in Chile and in the rest of the world. One of the main problems of a flexible work process is handling shiftwork systems with their economic, health, social, family and environmental consequences.

关键词： Shiftwork scheduling shifts AHR integration multidisciplinary group decision making

Niche segregation, competition, and urbanization

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Current Zoology 2018年第2期64卷 145-152页

作者： Anders PAPE MФLLER mario DiAz Ecologie Systematique Evolution CNRS Universite Paris-Sud AgroParisTech Universite Pari-Saclay OrsayCedex F-91400 France Department of Biogeography and Global Change (BGC-MNCN-CSIC) NationalMuseum of Natural Sciences CSIC c/Serrano 155bis Madrid E-28006 Spain

Urbanization of species is an ongoing process where successful urban colonizers usually obtain large fitness benefits. Mechanisms proposed to explain associations between urbanization and life-history traits are based on behavioral flexibility in food and habitat use and reduced fear responses. We test the novel hypothesis that interspecific competition for proximity to humans is driving urbanization. We recorded the distance during the breeding season to human habitation for 50 pairs of closely related bird species, where one was closely associated with humans while the other species was not. The degree of urbanization was larger as was range size and abundance in the species more closely associated to humans. Flight initiation distance was shorter, and species closely associated with humans were more abundant in ancestral rural habitats. Likewise, species more closely associated with humans reproduced earlier and during longer periods. These results are consistent with the hypothesis that urbanization is promoted by interspecific competition. Resulting isolation by urban habitat may further facilitate contemporary adaptation to urban environments.

关键词：都市化竞争分离壁龛基于行为繁殖季节种类城市

Changing Energy Consumption Behaviour: Individuals' Responsibility and Government Role

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Journal of Electronic Science and Technology 2015年第4期13卷 343-348页

作者： Mohamad Aldabas mario Gstrein Stephanie Teufel International Institute of Management in Technology (iimt) University of Fribourg

Renewable energy is clearly a very important topic nowadays. The risk and the damage that could be caused by conventional energy resources cannot be hidden. There is an enormous need that people start formulating a better attitude towards renewable energy and change their consumption behaviour. Otherwise, the future of environment and the coming generations is defiantly not going to be promising. This paper will discuss the importance of sustainable energy and how the energy related behaviour is created. It will present a framework to influence the current behaviour and push it to be more green oriented. It is also important to know till what limit are governments responsible in this change, and what are the tools that they have to push towards green direction.

关键词： Breaking bad habits green andrenewable energy energy consumption behavior.

Liver transplantation is beneficial regardless of cirrhosis stage or acute-on-chronic liver failure grade:A single-center experience

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World Journal of Gastroenterology 2022年第40期28卷 5881-5892页

作者： Eduardo Cervantes-Alvarez mario Vilatoba Nathaly Limon-de la Rosa Osvely Mendez-Guerrero David Kershenobich Aldo Torre Nalu Navarro-Alvarez PECEM Facultad de MedicinaUniversidad Nacional Autónoma de MéxicoMexico City 14080Mexico Department of Gastroenterology Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico City 14080Mexico Department of Trasplant Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico City 14080Mexico Department of Molecular Biology Universidad Panamericana School of MedicineMexico City 03920Mexico Department of Surgery University of Colorado Anschutz Medical CampusDenverCO 80045United States

BACKGROUND Liver transplantation for the most critically ill remains controversial;however,it is currently the only curative treatment *** To assess immediate posttransplant outcomes and compare the short(1 year)and long-term(6 years)posttransplant survival among cirrhotic patients stratified by disease *** We included cirrhotic patients undergoing liver transplantation between 2015 and 2019 and categorized them into compensated cirrhosis(CC),decompensated cirrhosis(DC),and acute-on-chronic liver failure(ACLF).ACLF was further divided into severity *** primary outcomes of interest were total days of intensive care unit(ICU)and hospital stay,development of complications and posttransplant survival at 1 and 6 *** 235 patients underwent liver transplantation(CC=11,DC=129 and ACLF=95).Patients with ACLF had a significantly longer hospital stay[8.0(6.0-13.0)vs CC,6.0(3.0-7.0),and DC 7.0(4.5-10.0);P=0.01]and developed more infection-related complications[47(49.5%),vs CC,1(9.1%)and DC,38(29.5%);P<0.01].Posttransplant survival at 1-and 6-years was similar among groups(P=0.60 and P=0.90,respectively).ACLF patients stratified according to ACLF grade[ACLF-1 n=40(42.1%),ACLF-2 n=33(34.7%)and ACLF-3 n=22(23.2%)],had similar ICU and hospital stay length(P=0.68,P=0.54),as well as comparable frequencies of overall and infectious posttransplant complications(P=0.58,P=0.80).There was no survival difference between ACLF grades at 1 year and 6 years(P=0.40 and P=0.15).CONCLUSION Patients may benefit from liver transplantation regardless of the cirrhosis *** patients have a longer hospital stay and frequency of infectious complications;however,excellent,and comparable 1 and 6-year survival rates support their enlisting and transplantation including those with ACLF-3.

关键词： Liver transplantation Acute-on-chronic liver failure Prognosis Survival analysis Critical care