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miniSCIDOM: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

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High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino M.Reimold E.Beyreuther F.-E.Brack F.Kroll j.Pawelke j.D.Schilz M.Schneider U.Schramm M.E.P.Umlandt K.Zeil T.Ziegler j.Metzkes-Ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany Technische Universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum Freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIDOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

Large eddy simulation of free-surface flows

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journal of Hydrodynamics 2017年第1期29卷 1-12页

作者： Richard j.McSherry Ken v.Chua Thorsten Stoesser School of Engineering Cardiff UniversityCardiffCF24 3AAUK

This paper introduces and discusses numerical methods for flee-surface flow simulations and applies a large eddy simula- tion （LES） based flee-surface-resolved CFD method to a couple of flows of hydraulic engineering interest. The advantages, dis- advantages and limitations of the various methods are discussed. The review prioritises interface capturing methods over interface tracking methods, as these have shown themselves to be more generally applicable to viscous flows of practical engineering interest, particularly when complex and rapidly changing surface topologies are encountered. Then, a LES solver that employs the level set method to capture flee-surface deformation in 3-D flows is presented, as are results from two example calculations that concern com- plex low submergence turbulent flows over idealised roughness elements and bluff bodies. The results show that the method is capable of predicting very complex flows that are characterised by strong interactions between the bulk flow and the free-surface, and permits the identification of turbulent events and structures that would be very difficult to measure experimentally.

关键词： Large eddy simulation free-surface level set method volume of fluid

Analysis of the geometrical dependence of auxetic behavior in reentrant structures by finite elements

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Acta Mechanica Sinica 2016年第2期32卷 295-300页

作者： v.H.Carneiro H.Puga j.Meireles Department of Mechanical Engineering University of Minho

Materials with a negative Poisson＇s ratio（PR）are called auxetics;they are characterized by expansion/contraction when tensioned/*** this counterintuitive behavior,they present very particular characteristics and mechanical *** models have been developed to justify and artificiall reproduce such materials＇ auxetic *** focus of this study is the exploration of a reentrant model by analyzing the variation in the PR of reentrant structures as a function of geometrical and base material *** is shown that,even in the presence of protruding ribs,there may not be auxetic behavior,and this depends on the geometry of each reentrant *** determined for these parameters can be helpful as approximate reference data in the design and fabrication of auxetic lattices using reentrant geometries.

关键词： Auxetic Poisson’s ratio Reentrant Finite element analysis Elasticity

Using emotions for the development of human-agent societies

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Frontiers of Information Technology & Electronic Engineering 2016年第4期17卷 325-337页

作者： j.A.RINCON j.BAjO A.FERNANDEZ v.jULIAN C.CARRASCOSA Department of Computer Systems and Computation Universitat Politecnica de Valencia Departamento de Inteligencia Artificial Universidad Politecnica de Madrid Centre for Intelligent Information Technologies Universidad Rey Juan Carlos

Human-agent societies refer to applications where virtual agents and humans coexist and interact transparently into a fully integrated environment. One of the most important aspects in this kind of applications is including emotional states of the agents(humans or not) in the decision-making process. In this sense, this paper presents the applicability of the jaCalIvE(jason Cartago implemented intelligent virtual environment) framework for developing this kind of society. Specifically, the paper presents an ambient intelligence application where humans are immersed into a system that extracts and analyzes the emotional state of a human group. A social emotional model is employed to try to maximize the welfare of those humans by playing the most appropriate music in every moment.

关键词： Multi-agent systems virtual environments Emotional agents

Numerical studies towards practical large-eddy simulation

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journal of Thermal Science 2007年第4期16卷 328-336页

作者： j.Boudet j.Caro L.Shao E.Lév(?)que LMFA Laboratoire

Large-eddy simulation developments and validations are presented for an improved simulation of turbulent internal flows. Numerical methods are proposed according to two competing criteria： numerical qualities （precision and spectral characteristics）, and adaptability to complex configurations. First, methods are tested on academic test-cases, in order to abridge with fundamental studies. Consistent results are obtained using adaptable finite volume method, with higher order advection fluxes, implicit grid filtering and ＂low-cost＂ shear-improved Smagorinsky model. This analysis particularly focuses on mean flow, fluctuations, two-point correlations and spectra. Moreover, it is shown that exponential averaging is a promising tool for LES implementation in complex geometry with deterministic unsteadiness. Finally, adaptability of the method is demonstrated by application to a configuration representative of blade-tip clearance flow in a turbomachine.

关键词： LES adaptable methods validation

Modeling limit force capacities of high force to volume lead extrusion dampers

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Frontiers of Structural and Civil Engineering 2021年第3期15卷 609-622页

作者： v.vISHNUPRIYA Geoffrey.W.RODGERS j.Geoffrey CHASE Department of Mechanical Engineering University of CanterburyChristchurch8140New Zealand QuakeCoRE NZ Centre for Earthquake Resilience Christchurch8041New Zealand

Lead extrusion dampers are supplemental energy-dissipation devices that are used to mitigate seismic structural *** volumetric sizes and high force capacities define high-force-to-volume(HF2v)devices,which can absorb significant response energy without sacrificial ***,the design of such devices for specific force capacities has proven difficult based on the complexities of their internal reaction mechanisms,leading to the adoption of empirical *** study developed upper-and lower-bound force capacity estimates from analytical mechanics based on direct and indirect metal extrusion for guiding *** derived equations are strictly functions of HF2v device geometric parameters,lead material properties,and extrusion *** upper-bound estimates from direct and indirect extrusion are denoted as(F_(UB,1),F_(UB,2))and(F_(UB,3),F_(UB,4)),respectively,and the lower-bound estimates are denoted as(F_(LB),F_(LB,1))based on the combination of extrusion and friction *** proposed models were validated by comparing the predicted bounds to experimental force capacity data from 15 experimental HF2v device *** experimental device forces all lie above the lower-bound estimates(F_(LB),F_(LB,1))and below the upper-bound estimates(F_(UB,1),F_(UB,2),F_(UB,4)).Overall,the(F_(LB),F_(UB,2))pair provides wider bounds and the(F_(LB,1),F_(UB,4)/F_(UB,1))pair provides narrower ***(F_(LB,1),F_(UB,1))pair has a mean lower-bound gap of 36%,meaning the lower bound was 74%of the actual device force on *** mean upper-bound gap was 33%.The bulge area and cylinder diameter of HF2v devices are key parameters affecting device *** relatively tight bounds provide useful mechanics-based predictive design guides for ensuring that device forces are within the targeted design range after manufacturing.

关键词： extrusion lead dampers upper and lower bound analytical modelling limit force

Tuning electronic properties of cobalt phthalocyanines for oxygen reduction and evolution reactions

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Science China Chemistry 2024年第1期67卷 398-407页

作者： jianlin jiang Zhen Liu Shuaijun Pan Xinnian Xia Bing Qin Yang Hu Xuxu Wang jiamin Lan Yu Gu Encai Ou Weijian Xu joseph j.Richardson Rui Guo SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082China College of Chemistry and Materials Science Hunan Agricultural UniversityChangsha 410128China Department of Chemical Engineering The University of MelbourneParkville 3010Australia College of Environmental Science and Engineering Hunan UniversityChangsha 410082China School of Engineering RMIT UniversityMelbourneVictoria 3001Australia

Metal–phthalocyanines are a class of catalytically active materials promising in energy conversion and storage fields(e.g.,electrocatalysis).However,understanding and controlling the electrochemical properties in metal-phthalocyanine systems is ***,we elucidate the electrocatalytic origins of a series of cobalt-phthalocyanine molecular catalysts and finetune their electronic properties at the atomic level,both experimentally and *** interactions between the cobalt center and the local coordination environment are regulated by introducing either electron-donating or electron-withdrawing groups on the phthalocyanine ligand,and the spin-orbit splitting of cobalt is increased by~0.15 ev compared with the nonsubstituted ***,the aminated cobalt phthalocyanine-based electrocatalysts exhibit low free energies in the ratedetermining steps of the oxygen reduction(-1.68 ev)and oxygen evolution reactions(0.37 ev).This contributes to the high electrocatalytic activity(e.g.,a halfwave potential of 0.84 v and an overpotential of 0.30 v at 10 mAcm^(-2)),featuring a high selectivity of a four-electron pathway(i.e.,a negligible by-product of hydrogen peroxide).These catalysts also exhibit exceptional kinetic current density(Tafel slope of 100 mv dec^(-1))in oxygen reduction reactions,in addition to a superior power density(158 mWcm^(-2))and a high cycling stability(>1,300 cycles)in Zn-air batteries,outperforming the commercial Pt/C and/or RuO2counterparts.

关键词： interfacial wettability molecular catalysts carbon nanotubes density functional theory electrochemistry

Analysis of regular and chaotic dynamics of the Euler-Bernoulli beams using finite difference and finite element methods

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Acta Mechanica Sinica 2011年第1期27卷 36-43页

作者： j.Awrejcewicz A.v.Krysko j.Mrozowski O.A.Saltykova M.v.Zhigalov Department Automation and Biomechanics Technical University of Lódz Department of Mathematics and Modeling Saratov State University

Chaotic vibrations of flexible non-linear Euler-Bernoulli beams subjected to harmonic load and with various boundary conditions（symmetric and non-symmetric）are studied in this *** of the obtained results is verified by the finite difference method（FDM）and the finite element method（FEM）with the Bubnov-Galerkin approximation for various boundary conditions and various dynamic regimes（regular and non-regular）.The influence of boundary conditions on the Euler-Bernoulli beams dynamics is studied mainly,dynamic behavior *** parameters { ωp,q0 } is reported,and scenarios of the system transition into chaos are illustrated.

关键词： Euler-Bernoulli beams · Chaos · Finite differ-ence method · Finite element method

Clinical and Demographic Profile of Women with Uterine Fibroids Living in Puerto Rico

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Open journal of Obstetrics and Gynecology 2024年第9期14卷 1347-1362页

作者： Edwin Y. Soto-velázquez Alexander j. jaramillo-Cañas Shania N. Aponte-Paris Gabriela v. Martínez-Marrero Irazu S. Guinan Gabrielle A. Rivera-Maldonado Alexandra Novas Pedro L. Cruz-Rosa Idhaliz Flores-Caldera Maricarmen Colón-Diaz Department of Physiology and Pathology San Juan Bautista School of Medicine Caguas Puerto Rico United States Ponce Research Institute Ponce Health Sciences University Ponce Puerto Rico United States

Introduction: Uterine leiomyomas, or fibroids, are prevalent benign tumors affecting up to 70% of reproductive-age women in the United States, significantly impacting productivity and quality of life. Despite their commonality, the epidemiology and clinical patterns of leiomyomas in Puerto Rico remain inadequately researched. Methods: This study conducted a secondary data analysis using clinical, menstrual cycle characteristics, and demographic data from self-administered questionnaires of women undergoing diagnostic laparoscopy for endometriosis in Puerto Rico. Chi-square tests and t-tests analyzed categorical and continuous variables, respectively (p Results: Among 1,610 endometriosis cases, 312 included uterine fibroids. Prevalence estimates were 10.3% (40 years). Primiparous women averaged 22.14 years, with 40.71% having 2 - 3 pregnancies and 26.28% experiencing miscarriages. Symptoms included infertility (29.5%), dyspareunia (40.7%), severe pain (50%), and dysmenorrhea (75.6%). Comorbidities included ovarian cysts (52.2%) and abnormal uterine bleeding (37.8%). Conclusions: Advanced age, parity, and comorbidities like diabetes and hypertension were prevalent in our cohort. Understanding the epidemiological profile of women living in Puerto Rico with uterine fibroids is crucial for improving diagnostic awareness and enhancing patient care.

关键词： Uterine Fibroids Puerto Rico Epidemiology Dysmenorrhea Abnormal Uterine Bleeding