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Light Front Fermion Model Propagation

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Communications in Theoretical Physics 2013年第7期60卷 55-68页

作者： jorge Henrique Sales Alfredo Takashi Suzukil Universidade Estadual de Santa Cruz km 16 Rodovia Jorge Amado-45662-900-Ilhéus BA Brazi Physics and Engineering Department Southern Adventist University 4881 Taylor Circle-Collegedale TN 37315 USA Instituto de Física Terica UNESP-Universidade Estadual Paulista Rua Dr. Bento Teobaldo Ferraz 271-Bloco II Barra Funda 01140-070 So Paulo So Paulo Brazil

In this work we consider the propagation of two fermion fields interacting with each other by the exchange of intermediate scalar bosons in the light front. We obtain the corrections up to fourth order in the coupling... 详细信息

关键词： light front Fermions propagations

Key innovations in ruminant evolution: a paleontological perspective

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Integrative Zoology 2014年第4期9卷 412-433页

作者： Daniel DeMIGUEL Beatriz AZANZA jorge MORALES Catalan Institute of Paleontology Miquel Crusafont Autonomus University of BarcelonaBarcelonaSpain Department of Earth Sciences University of ZaragozaUniversity Research Institute in Environmental SciencesZaragozaSpain Department of Paleobiology National Museum of Natural SciencesMadridSpain

Key innovations are newly acquired structures that permit the performance of a new function and open new adaptive zones,and are,therefore,of paramount significance for understanding the history of the Ruminantia,particularly its diversification through the *** we review and discuss what is known about these evolutionary novelties,with special emphasis on the appearance and evolution of cranial appendages and high-crowned(or hypsodont)*** appendages probably favored the diversification of pecorans by being structures strongly related to sexual selection,whereas the acquisition of hypsodont teeth could have expanded potential dietary breadth and allowed species to extend diets into the grazing range without eliminating browsing as a potential *** analyzed in conjunction with patterns of faunal diversity and in the context of climatic changes,it seems that the overall view that ruminant cranial appendages and hypsodonty may have started responding to increased patterns of seasonality and the opening-up of ecosystems is roughly ***stead,they occurred through several distinct pulses and varied widely among *** review is,to our knowledge,the first to highlight that the evolution of these innovations has been far from constant and uniform through ***,we identify that both a first attempt to increase hypsodonty starting in the early Miocene and a first evolution of antlers and pronghorns were interrupted as a consequence of wide climatic fluctuations in the early-middle Miocene transition.

关键词： Artiodactyla climate change cranial appendages diversity hypsodonty

Effect of an electron gas on a neutron-rich nuclear pasta

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Nuclear Science and Techniques 2015年第2期26卷 75-82页

作者： jorge Alberto Lopez Enrique Ramirez-Homs Department of Physics University of Texas at El Paso

We studied the role that electron gas has on the formation of nuclear structures at subsaturation densities and low temperatures(T<1 Me V).Using a classical molecular dynamics model we studied isospin symmetric and asymmetric matter at subsaturation densities and low temperatures varying the Coulomb interaction *** effect of such variation was quantified on the fragment size multiplicity,the inter-particle distance,the isospin content of the clusters,the nucleon mobility and cluster persistence,and on the nuclear structure *** found that the presence of an electron gas distributes matter more evenly,disrupts the formation of larger objects,reduces the isospin content,and modifies the nucleon average displacement,but does not affect the inter-nucleon distance in *** nuclear structures are also found to change shapes by different degrees depending on their isospin content,temperature and density.

关键词：电子气体分子动力学模型面食中子相互作用强度核结构同位旋平均位移

Calculations of Optical Rotation from Density Functional Theory

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Chinese Physics Letters 2007年第5期24卷 1207-1209页

作者： Antǒnio Canal Neto Francisco Elias jorge Departamento de Fisica Universidade Federal do Espírito Santo 29060-900 Vitória ES Brazil

Density function theory calculations of frequency-dependent optical rotations [α]ω for three rigid chiral molecules are reported. Calculations have been carried out at the sodium D line frequency, using the ADZP basis set and a wide variety of functionals. Gauge-invariant atomic orbitals are used to guarantee origin-independent values of [ω]D. In addition, study of geometry dependence of [ω]D is reported. Using the geometries optimized at the B3LYP/ADZP level, the mean absolute deviation of B3LYP/ADZP and experimental laiD values yields 60.1°/（dm g/cm^3）. According to our knowledge, this value has not been achieved until now with any other model.

关键词： MOLECULAR WAVE-FUNCTIONS BASIS-SETS MP2 HF

Marriage Market with Indifferences: A Linear Programming Approach

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Journal of the Operations Research Society of China 2023年第1期11卷 219-242页

作者： Noelia Juarez Pablo A.Neme jorge Oviedo Instituto de Matemática Aplicada San Luis IMASLRedNIEUniversidad Nacional de San Luis and CONICETD5700HHWSan LuisRepublica Argentina

We study stable and strongly stable matchings in the marriage market with indifference in their *** characterize the stable matchings as integer extreme points of a convex *** give an alternative proof for the integrity of the strongly stable matching ***,we compute men-optimal(women-optimal)stable and strongly stable matchings using linear *** preferences are strict,we find the men-optimal(women-optimal)stable matching.

关键词： Matching markets The marriage market with indifferences Optimal stable matchings Linear programming

Design and Manufacturing Strategies for Fused Deposition Modelling in Additive Manufacturing:A Review

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Chinese Journal of Mechanical Engineering 2019年第3期32卷 1-16页

作者： Hugo I.Medellin-Castillo jorge Zaragoza-Siqueiros Advanced Design and Manufacturing Laboratory Facultad de IngenieríaUniversidad Autónoma de San Luis Potosí

Although several research works in the literature have focused on studying the capabilities of additive manufacturing(AM) systems, few works have addressed the development of Design for Additive Manufacturing(DfAM) knowledge,tools, rules, and methodologies, which has limited the penetration and impact of AM in industry. In this paper a comprehensive review of design and manufacturing strategies for Fused Deposition Modelling(FDM) is ***, several DfAM strategies are proposed and analysed based on existing research works and the operation principles, materials, capabilities and limitations of the FDM process. These strategies have been divided into four main groups: geometry, quality, materials and sustainability. The implementation and practicality of the proposed DfAM is illustrated by three case studies. The new proposed DfAM strategies are intended to assist designers and manufacturers when making decisions to satisfy functional needs, while ensuring manufacturability in FDM ***, many of these strategies can be applied or extended to other AM processes besides FDM.

关键词： Additive manufacturing(AM) Design for additive manufacturing(DfAM) Fused Deposition Modelling(FDM) Design and manufacturing strategies

Novel experimental techniques to assess the time-dependent deformations of geosynthetics under soil confinement

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第2期13卷 410-419页

作者： Carina Maia Lins Costa jorge Gabriel Zornberg Department of Civil Engineering Federal University of Rio Grande do NorteAv.Senador Salgado Filho 3000NatalRio Grande do Norte59078-970Brazil Department of Civil Architectural and Environmental Engineering The University of Texas at Austin301 E.Dean KeetonAustinTX78712-0280USA

A new experimental approach to assess the impact of soil confinement on the long-term behavior of geosynthetics is presented in this *** experimental technique described herein includes a novel laboratory apparatus and the use of different types of tests that allow generation of experimental data suitable for evaluation of the time-dependent behavior of geosynthetics under soil *** soil-geosynthetic interaction equipment involves a rigid box capable of accommodating a cubic soil mass under plane strain conditions.A geosynthetic specimen placed horizontally at the mid-height of the soil mass is subjected to sustained vertical pressures that,in turn,induce reinforcement axial loads applied from the soil to the *** previously reported studies on geosynthetic behavior under soil confinement,the equipment was found to be particularly *** minor setup modifications,not only interaction tests but also in-isolation geosynthetic stress relaxation tests and soil-only tests under a constant strain rate can be conducted using the same ***,the time histories of the reinforcement loads and corresponding strains are generated throughout the *** from typical tests conducted using sand and a polypropylene woven geotextile are presented to illustrate the proposed experimental *** testing procedure was found to provide adequate measurements during tests,including good repeatability of test *** soilegeosynthetic interaction tests were found to lead to increasing geotextile strains with time and decreasing reinforcement tension with *** test results highlighted the importance of measuring not only the time history of displacements but also that of reinforcement loads during *** approach of using different types of tests to analyze the soilegeosynthetic interaction behavior is an innovation that provides relevant insight into the impact of soil confinement on the time-dependent deformations of geos

关键词： Geosynthetics Geotextile Creep Stress relaxation Reinforced soil Long-term deformation

Dipole (hyper)polarizabilities of neutral silver clusters

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Chinese Physics B 2016年第12期25卷 217-222页

作者： Francisco E jorge Luiz G M de Macedo Departarnento de Fisica Universidade Fedoral do Espirito Santo 29060-900 Vitoria Brazil Unidade Academica de Fisica Universidade Federal de Campina Grande 58429-900 Campina Grande Brazil Faculdade de Biotecnologia ICB Universidade Federal do Para 66075-110 Belem Brazil

At the Douglas-Kroll-Hess （DKI4） level, the B3PW91 functional along with the all-eleclron relativistic basis sets of valence triple and quadruple zeta qualities are used to determine the structure, stability, and electronic properties of the small silver clusters （Agn, n ≤ 7）. The results presented in this study are in good agreement with the experimental data and theoretical values obtained at a higher level of theory from the literature. Static polarizability and hyperpolarizability are also reported. It is verified that the mean dipole polarizability per atom exhibits an odd-even oscillation and that the polarizability anisotropy is directly related to the cluster shape. In this article, the first study of hyperpolarizabilities of small silver clusters is presented. Except for the monomer, the second hyperpolarizabilities of the silver clusters are significantly larger than those of the copper clusters.

关键词： B3PW91 functional all-electron basis sets non-relativistic and DKH2 calculations silver clusters,dipole (hyper)polarizabilities

On the possibility that PbZrO_(3) not be antiferroelectric

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npj Computational Materials 2021年第1期7卷 1812-1821页

作者： Hugo Aramberri Claudio Cazorla Massimiliano Stengel jorge Íñiguez Materials Research and Technology Department Luxembourg Institute of Science and Technology5 Avenue des Hauts-FourneauxL-4362 Esch/AlzetteLuxembourg Departament de Física Universitat Politècnica de CatalunyaCampus Nord B4-B5Barcelona 08034Spain Institut de Ciència de Materials de Barcelona(ICMAB-CSIC) Campus UAB08193 BellaterraSpain ICREA-InstitucióCatalana de Recerca i Estudis Avançats 08010 BarcelonaSpain Department of Physics and Materials Science University of Luxembourg41 Rue du BrillBelvaux L-4422Luxembourg

Lead zirconate(PbZrO_(3))is considered the prototypical antiferroelectric material with an antipolar ground ***,several experimental and theoretical works hint at a partially polar behaviour in this compound,indicating that the polarization may not be completely *** this work,we propose a simple ferrielectric structure for lead ***-principles calculations reveal this state to be more stable than the commonly accepted antiferroelectric phase at low temperatures,possibly up to room temperature,suggesting that PbZrO_(3)may not be antiferroelectric at ambient *** discuss the implications of our discovery,how it can be reconciled with experimental observations and how the ferrielectric phase could be obtained in practice.

关键词： ferroelectric ambient phase