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Three-Dimensional Fluid-Structure Interaction Case Study on Cubical Fluid Cavity with Flexible Bottom

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Journal of Marine Science and Application 2017年第4期16卷 382-394页

作者： Stefano Ghelardi Cesare Rizzo diego villa DITEN - Polo Navale Università degli Studi di Genova via Montallegro Genova 1 I-16145 Italy

In this paper, we report our study on a numerical fluid-structure interaction problem originally presented by Mok et al.(2001) in two dimensions and later studied in three dimensions by Valdés Vazquez(2007), Lombardi(2012), and Trimarchi(2012). We focus on a 3D test case in which we evaluated the sensitivity of several input parameters on the fluid and structural results. In particular, this analysis provides a starting point from which we can look deeper into specific aspects of these simulations and analyze more realistic cases, e.g., in sails design. In this study, using the commercial software ADINATM, we addressed a well-known unsteadiness problem comprising a square box representing the fluid domain with a flexible bottom modeled with structural shell elements. We compared data from previously published work whose authors used the same numerical approach, i.e., a partitioned approach coupling a finite volume solver(for the fluid domain) and a finite element solver(for the solid domain). Specifically, we established several benchmarks and made comparisons with respect to fluid and solid meshes, structural element types, and structural damping, as well as solution algorithms. Moreover, we compared our method with a monolithic finite element solution method. Our comparisons of new and old results provide an outline of best practices for such simulations.

关键词： fluid-structure interaction benchmark finite volume method finite element method partitioned monolithic ADINA^(TM)

Numerical Evaluation of Rudder Performance Behind a Propeller in Bollard Pull Condition

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Journal of Marine Science and Application 2018年第2期17卷 153-164页

作者： diego villa Michele Viviani Giorgio Tani Stefano Gaggero Dario Bruzzone Carlo Bonvino Podenzana Department of Electrical Electronics and Telecommunication Engineering and Naval Architecture– DITENUniversity of Genova16145 GenoaItaly

Correct evaluation of rudder performance is a key issue in assessing ship *** paper presents a simplified approach based on a viscous flow solver to address propeller and rudder *** flow solvers have been applied to this type of problems,but the large computational requests limit(or even prevent)their application at a preliminary ship design *** on this idea,a simplified approach to include the propeller effect in front of the rudder is considered to speed up the *** on the concept of body forces,this approach enables sufficiently fast computation for a preliminary ship design stage,therebymaintaining its *** define the limitations of the proposed procedure,an extensive analysis of the simplified method is performed and the results are compared with experimental data presented in the ***,the reported results show the capability of the body-force approach to represent the inflow field to the rudder without the full description of the propeller,also with regard to the complex bollard pull ***,the rudder forces are satisfactorily predicted at least with regard to the lift ***,the drag force evaluation ismore problematic and causes higher ***,these discrepancies may be accepted due to their lower influence on the overall ship maneuverability performance.

关键词： Rudder-propeller interaction RANS Body forces Actuator disk Bollard pull

Diplomatic Relations and Investment Location of Chinese Multinationals:An International Political Economy Perspective

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China & World Economy 2024年第5期32卷 87-112页

作者： diego Quer Department of Management University of AlicanteSpain

Past research has suggested that diplomacy can play a significant role as a mechanism to pave the way for multinational enterprises(MNEs)in foreign *** on the international political economy perspective,this article analyzes the influence of the diplomatic activities of the Chinese government on the location of Chinese *** develops several hypotheses regarding the influence of three essential tools in the Chinese government's current diplomatic agenda:high-level visits by the Chinese President,the establishment of Confucius Institutes,and the Belt and Road Initiative(BRI).The empirical analysis is based on a sample of 972 country-year observations from 2013 to *** results show that high-level government visits and Confucius Institutes positively impacted the location of China's outward foreign direct investments,with the effect being lower in BRI *** impact of Confucius Institutes was higher for state-owned enterprises.

关键词： diplomacy international political economy location decisions multinational enterprises

A Rapid Parameter of Enzyme-Treated Cellulosic Material Revealed by Reducing Sugar Release

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Journal of Renewable Materials 2024年第3期12卷 539-551页

作者： Verônica Távilla Ferreira Silva Adriane Maria Ferreira Milagres Departamento de Biotecnologia Escola de Engenharia de LorenaUniversidade de São PauloLorenaSP12602-810Brazil

This study was conducted to evaluate the effectiveness of enzymes in purifying and reducing the degree of polymerization of cellulose for the production of dissolving *** goal was to determine the contributions of xylanase(X)and endoglucanase(EG)in the treatment of pulp,specifically by quantifying the formation of soluble and insoluble reducing sugars using the dinitrosalycilic acid(DNS)***,the release of soluble reducing sugars(RSSol)was enhanced after xylanase treatment,while endoglucanase(EG)treatment led to changes in insoluble reducing sugars(RSIns).The maximum synergism was observed for RSIns when a high ratio of endoglucanase to xylanase(320EG:5X/g pulp)was *** relative contribution of endoglucanase to RSins was determined to be 15.6%of the total reducing *** viscosity of pulps treated with xylanase decreased only by 7%,whereas endoglucanase treatment significantly reduced viscosity by 45%.Modifications in the particle size were observed after pulp treatment with the combination of endoglucanase and *** summary,the DNS test is a rapid and effective method for evaluating the efficiency of enzyme treatments on *** measurement of RSIns correlates with changes in pulp viscosity to different extents,providing valuable insights into the effectiveness of enzyme treatments.

关键词： Endoglucanase xylanase cellulose fiber pulp synergism

ChatGPT and exercise prescription:Human *** or human plus machine?

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Journal of Sport and Health Science 2024年第5期13卷 661-662页

作者： Timothy Gustavo Cavazzotto diego Bessa Dantas Marcos Roberto Queiroga Department of Physical Education Midwestern Parana State UniversityParana 85040-167Brazil Postgraduate Program in Physical Education UEM-UEL State University of LondrinaParana 86057-970Brazil

The power of artificial intelligence(AI)to create stories,music,art,and other creative projects has been demonstrated and criticized over recent decades in media,mainly because of the idea that AI will replace human *** recently,in November 2022,reactions to Chat Generative Pre-training Transformer(ChatGPT)release for public use reverberated in news and social media headlines,while its users exceeded100 million in just a few *** is a natural language processing program created by AI non-profit OpenAI Inc.

关键词： prescription replace Human

Laser-induced plasma formation in water with up to 400 mJ double-pulse LIBS

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Plasma Science and Technology 2024年第1期26卷 93-100页

作者： Marion HENKEL Michelle SIEMENS Ralf METHLING Benjamin EMDE Jörg HERMSDORF Steffen FRANKE diego GONZALEZ Leibniz Institute for Plasma Science and Technology(INP) Felix-Hausdorff-Straße 2Greifswald 17489Germany Laser Zentrum Hannover e.V.(LZH) Hollerithallee 8Hannover 30419Germany

Double-pulse LIBS is a promising technique for deep-sea *** measurements in shallow water with up to 400 mJ each pulse were done to select laser parameters which promote optimized spectral line emission from plasma even at elevated pressures,where line broadening until loss of most of the spectral information can *** emission spectroscopy,using a Czerny-Turner spectrometer,has been applied to investigate the dependence of the emitted radiation on laser parameters and hydrostatic *** has been found,that higher laser pulse energies,especially with short pulse delay as required in high water pressure,can also have an adverse effect on the measured spectrum.

关键词： double-pulse LIBS underwater plasma formation emission spectrosocpy

Evolution, divergence, and convergence in the mandibles of opossums (Didelphidae, Didelphimorphia)

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Current Zoology 2024年第4期70卷 488-504页

作者： Franciscodas Chagas Silva-Neto Silvia E.Pavan diego Astua Laboratorio de Mastozoologia Departamento de ZoologiaUniversidade Federal de Pernambuco.Av.Prof.Moraes Regos.n.Cidade Universitaria.50670-901RecifePEBrazil Department of Biological Sciences California State Polytechnic UniversityHumboldt1Harpst StreetArcataCA95521USA

Didelphid marsupials are considered a morphologically unspecialized group with a generalist diet that includes vertebrates,invertebrates,and plant *** cranium and scapula variation has alreadybeen examined within Didelphidae,variation inmandible shape,usually associated with diet or phylogeny in other mammalian groups,has not yet been properly assessed in the *** evaluated the variation in mandible shape and size of didelphids(2470 specimens belonging to 94 species)using 2D geometric *** classified the diet of the didel-phids into four broad categories to assess whether morphospace ordination relates to dietary *** also provided the most comprehensive phylogeny for the family(i23 out of the 126 living species)using 10 nuclear and mitochondrial *** then mapped mandible size and shape onto that phylogeny for 93 selected taxa and ancestral size and shapes were reconstructed by *** found phylogenetically structured variation in mandible morphology between didelphid groups,and our results indicate that they have a significant phylogenetic *** main axis of shape variation is poorly related to size,but the second is strongly allometric,indicating that allometry is not the main factor in shaping morphological diversity on their *** results indicate that the shape and size of the ancestral mandible of didelphids would be similar to that of the current species of the genus Marmosa.

关键词： mandible Didelphimorphia morphological evolution allometry phylogeny diet.

Exploring the size of Andean condor foraging groups along an altitudinal and latitudinal gradient in the Tropical Andes: Ecological and conservation implications

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Current Zoology 2024年第2期70卷 225-232页

作者： diego Mendez Felix Hernan Vargas JoséHernan Sarasola Pedro P.Oleaa Departamento de Ecologia Universidad Autonoma de MadridCalle Darwin 228049MadridSpain Museo Nacional de Historia Natural Calle 26 s/nCota CotaLa PazBolivia The Peregrine Fund 5668 West Flying Hawk LaneBoiseID 83709USA Centro para el Estudio y Conservacion de Aves Rapaces en Argentina(CECARA) Universidad Nacional de La PampaAvda Uruguay 1516300 Santa RosaLa PampaArgentina Instituto de las Ciencias Ambientales y de la Tierra de La Pampa(INCITAP-CONICET) Avda.Uruguay 1516300 Santa RosaLa PampaArgentina Centro de Investigacion en Biodiversidad y Cambio Global(CIBC-UAM) Universidad Autonoma de MadridMadridCalle Darwin 228049Madrid Snain

Patterns of variation in the size of vulture foraging groups,and their ecological causes and consequences,remain litle explored despite strong links with the carrion recycling service that this key functional group *** documented the group size-frequency pattern of Andean con-dors Vultur gryphus gathered to feed on 42 equine carcasses experimentally placed in Bolivia,between 2012 and 2019,along an elevation range of 1,300-4,500 m *** on the location(altitude and latitude)of the foraging groups,we examined the relationship between their size and species'population parameters(size and trend),habitat conditions,and livestock carcass availability and *** utilized a high frequency(93%)of carcasses forming groups that ranged from 1 to 80 individuals(mean=25,median=18)and shaped a"lazy-J curve"typical pattern of size-frequency distribution whereby few groups(5,12%)were large(>55 individuals)and most(21,50%)were relatively small(<19 individuals).Group size related to altitude in that most larger groups formed at lower sites(below c.3,000 m asl),likely following an altitudinal gradient whereby larger groups are more likely to form around larger carcasses(i.e.,cattle),which are more likely to occur at lower *** of population size,group size could be an adaptive response of condors via local enhancement for improving individual scavenging *** information gaps on this topic still exist,thus we provide a set of questions to address them,especially amidst the unrestricted impacts of human activities that condition vulture survival globally.

关键词： condor andino fusion-fission dynamics group size scavenger social foraging vultures.

Efficient fidelity estimation: alternative derivation and related applications

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Communications in Theoretical Physics 2024年第9期76卷 18-22页

作者： diego S Starke Marcos L W Basso Jonas Maziero Physics Department Center for Natural and Exact Sciences Federal University of Santa Maria Center for Natural and Human Sciences Federal University of ABC Avenue of the States

In[***.A 107 012427 (2023)],Baldwin and Jones prove that Uhlmann–Jozsa’s fidelity between two quantum statesρandσ,i.e.,■,can be written in a simplified form as ■.In this article,we give an alternative proof of this result,using a function power series expansion and the properties of the trace *** approach not only reinforces the validity of the simplified expression but also facilitates the exploration of novel dissimilarity functions for quantum states and more complex trace functions of density operators.

关键词： Chebyshev polynomials efficient fidelity estimation Rényi entropy Ulhmann-Jozsa fidelity