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Maneuvering Modeling and simulation of AUV Dynamic systems with Euler-Rodriguez Quaternion Method

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China Ocean Engineering 2013年第3期27卷 403-416页

作者： C.W.Chen j.s.Kouh j.f.Tsai Department of science Engineering and Ocean Engineering National Taiwan University

The purpose of this study is to develop maneuvering models and systems of a simulator to improve the motion performance of autonomous underwater vehicles （AUVs） at the preliminary design stages in advance. The AUVs simulation systems based on the standard submarine equations of motion in six-degree-of-freedom （6-DOf） integrated with the Euler-Rodriguez quaternion method for representing singularity-free AUV attitude and time-saving calculation, and with a nonlinear control model for maneuvering and depth control simulations, time-marching in the fourth-order Runge-Kutta scheme. for validation of the simulation codes, results of the IsiMI AUV open-loop tests including turning test and zigzag test as well as an AUV simulator on the basis of Euler-angle method were used to compare with the quaternion-based AUV simulator. The computational results from the proposed simulator agree well with those from both the IsiMI AUV experiments and the Euler-angle based simulations. Additionally, a new maneuvering procedure, namely ＂put-out＂ was implemented to test directional stability for a large-scale AUV in the proposed AUV simulator that can be considered for vehicles in space as well as in constrained planes.

关键词： autonomous underwater vehicle (.4 UV) Euler-Rodriguez quaternion hydrodynamics maneuvering systemdynamics

Accuracy details in realistic CfD modeling of an industrial centrifugal pump in direct and reverse modes

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journal of Thermal science 2010年第6期19卷 491-499页

作者： j.C. Páscoa f. j. silva j.s. Pinheiro D.j. Martins Department of Electromechanical Engineering Center for Aerospace Sciences and Technology University of Beira Interior EfAfLU Bombas e Ventiladores s.A. R. S. Brás 269 Apartado 23 4494-909 Póvoa do Varzim Portugal

Numerical computation of the flowfield inside a pump is herein used as a numerical laboratory, subject to the limitations of modeling assumptions and to experimental verification. A numerical computation of the flow inside a real industrial centrifugal pump is performed that includes a very sophisticated geometry. Conversely to other computations, in this test case no simplification of the geometry was introduced. Numerical computations are obtained using spalart-Allmaras turbulence model. A detailed analysis of the turbulent flowstructure is performed for the design point and two off design conditions. Additional computations were performed in order to compare the numerical and experimental pump characteristics; these were obtained under normalized testing conditions. further computations are presented for the pump working in reverse turbine mode (PAT). Detailed analyses of the flow allow a comparison of the internal flow losses when the pump is operating in direct and reverse mode. This is also useful to help in the selection of an adequate pump geometry that can work in both modes with best efficiency.

关键词： centrifugal pump impeller turbulence modeling spalart-Allmaras PAT

Performance and calibration of quark/gluon-jet taggers using 140 fb^(-1) of pp collisions at √s=13 TeV with the ATLAs detector

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Chinese Physics C 2024年第2期48卷 1-25页

作者： G. Aad B. Abbott K. Abeling N.j. Abicht s.H. Abidi A. Aboulhorma H. Abramowicz H. Abreu Y. Abulaiti B.s. Acharya C. Adam Bourdarios L. Adamczyk s.V. Addepalli M.j. Addison j. Adelman A. Adiguzel T. Adye A.A. Affolder Y. Afik M.N. Agaras j. Agarwala A. Aggarwal C. Agheorghiesei A. Ahmad f. Ahmadov W.s. Ahmed s. Ahuja X. Ai G. Aielli A. Aikot M. Ait Tamlihat B. Aitbenchikh I. Aizenberg M. Akbiyik T.P.A. Åkesson A.V. Akimov D. Akiyama N.N. Akolkar K. Al Khoury G.L. Alberghi j. Albert P. Albicocco G.L. Albouy s. Alderweireldt M. Aleksa I.N. Aleksandrov C. Alexa T. Alexopoulos f. Alfonsi M. Algren M. Alhroob B. Ali H.M.j. Ali s. Ali s.W. Alibocus M. Aliev G. Alimonti W. Alkakhi C. Allaire B.M.M. Allbrooke j.f. Allen C.A. Allendes flores P.P. Allport A. Aloisio f. Alonso C. Alpigiani M. Alvarez Estevez A. Alvarez fernandez M. Alves Cardoso M.G. Alviggi M. Aly Y. Amaral Coutinho A. Ambler C. Amelung M. Amerl C.G. Ames D. Amidei s.P. Amor Dos santos K.R. Amos V. Ananiev C. Anastopoulos T. Andeen j.K. Anders s.Y. Andrean A. Andreazza s. Angelidakis A. Angerami A.V. Anisenkov A. Annovi C. Antel M.T. Anthony E. Antipov M. Antonelli f. Anulli M. Aoki T. Aoki j.A. Aparisi Pozo M.A. Aparo L. Aperio Bella C. Appelt A. Apyan N. Aranzabal s.j. Arbiol Val C. Arcangeletti A.T.H. Arce E. Arena j-f. Arguin s. Argyropoulos j.-H. Arling O. Arnaez H. Arnold G. Artoni H. Asada K. Asai s. Asai N.A. Asbah j. Assahsah K. Assamagan R. Astalos s. Atashi R.j. Atkin M. Atkinson H. Atmani P.A. Atmasiddha K. Augsten s. Auricchio A.D. Auriol V.A. Austrup G. Avolio K. Axiotis G. Azuelos D. Babal H. Bachacou K. Bachas A. Bachiu f. Backman A. Badea P. Bagnaia M. Bahmani A.j. Bailey V.R. Bailey j.T. Baines L. Baines O.K. Baker E. Bakos D. Bakshi Gupta V. Balakrishnan R. Balasubramanian E.M. Baldin P. Balek E. Ballabene f. Balli L.M. Baltes W.K. Balunas j. Balz E. Banas M. Bandieramonte A. Bandyopadhyay s. Bansal L. Barak M. Barakat E.L. Barberio D. Barberis M. Barbero M.Z. Barel K.N. Barends T. Barillari M-s. Barisits T. Barklow P. Baron D.A. Baron Mo The ATLAs Collaboration

The identification of jets originating from quarks and gluons,often referred to as quark/gluon tagging,plays an important role in various analyses performed at the Large Hadron Collider,as standard Model measurements and searches for new particles decaying to quarks often rely on suppressing a large gluon-induced *** paper describes the measurement of the efficiencies of quark/gluon taggers developed within the ATLAs Collaboration,using √s=13 TeV proton–proton collision data with an integrated luminosity of 140 fb^(-1) collected by the ATLAs *** taggers with high performances in rejecting jets from gluon over jets from quarks are studied:one tagger is based on requirements on the number of inner-detector tracks associated with the jet,and the other combines several jet substructure observables using a boosted decision tree.A method is established to determine the quark/gluon fraction in data,by using quark/gluon-enriched subsamples defined by the jet *** in tagging efficiency between data and simulation are provided for jets with transverse momentum between 500 GeV and 2 TeV and for multiple tagger working points.

关键词： ATLAs jET QUARK GLUON TAGGING

Tubular Heat Enhancement Using Twisted Tape Inserts with Large Holes

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Energy Engineering 2024年第2期121卷 273-290页

作者： Ali jaber Abdulhamed Aws Al-Akam Wisam j.Khudhayer Ali sabri Allw faculty of Engineering-Al-Mussayib University of BabylonHillaBabylon15001Iraq

Heat augmentation techniques play a vital role in the heating and cooling processes in industries,including solar collectors and many applications that utilize heat *** studies are based on inserting fillers inside the tubes to enhance heat *** investigation considered the effects of twisted tapes with large holes on a tubular heat exchanger’s(HX)heat transmission,pressure drop,and thermal boosting *** the experimental section,counter-swirl flow generators used twisted tapes with pairs of 1.0 cm-diameter holes and changes in porosity(Rp)at 1.30%and 2.70%.In the experiments,air was utilized as a working fluid in a tube with a circular *** turbulent flow was considered,with Reynolds numbers(Re)domain from 4800 to 9500,and a boundary condition with a uniform wall heat flux was *** findings expound that when the number of holes rose,the Nusselt number(Nu),the factor of friction(f),and the thermal enhancement factor(η)all increased as ***,as the friction factor increased,the Nusselt number of the tape-equipped tube was noticeably ***,it was discovered that the friction factor was between 70%and 94%lower than the values of the tube without tape,while the(Nu)was between 87%and 97%higher than the conventional tube *** maximum value ofηis 89%.According to the experimental results,empirical correlations for Nu,f,andηwere also generated.

关键词： Tubular heat exchanger tape inserts twisted tape

支架特异性脂肪衰减指数与PCI术后靶血管血运重建相关

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国际医学放射学杂志 2024年第2期 251-252页

作者： f.Xu C.C.Wang Q.Tao j.Zhang M.M.Zhao s.W.shi 潘红利

摘要目的探讨支架特异性血管周围脂肪衰减指数（fAI）在支架植入病人中的临床相关性。方法回顾性纳入162例在支架植入后接受连续冠状动脉CT血管成像

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Impact of payment source, referral site, and place of residence on outcomes after allogeneic transplantation in Mexico

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World journal of Transplantation 2024年第2期14卷 76-87页

作者： Andrés Gómez-De León Yesica A López-Mora Valeria García-Zárate Ana Varela-Constantino sergio U Villegas-De Leon Xitlaly j González-Leal Raúl del Toro-Mijares Anna C Rodríguez-Zúñiga juan f Barrios-Ruiz Victor Mingura-Ledezma Perla R Colunga-Pedraza Olga G Cantú-Rodríguez César H Gutiérrez-Aguirre Luz Tarín-Arzaga Elías E González-López David Gómez-Almaguer Hematology service Universidad Autónoma de Nuevo LeónFacultad de Medicina y Hospital Universitario Dr.JoséEleuterio GonzálezMonterrey 64460Nuevo LeónMexico Hemato-logy service Clínica Gómez AlmaguerMonterrey 64710Nuevo LeónMexico Hematology service Instituto Tecnológico de Estudios Superiores de MonterreyTec SaludEscuela de Medicina Ignacio SantosMonterrey 64710Nuevo LeónMexico

BACKGROUND The impact of social determinants of health in allogeneic transplant recipients in low-and middle-income countries is poorly *** observational study analyzes the impact of place of residence,referring institution,and transplant cost coverage(out-of-pocket vs government-funded vs private insurance)on outcomes after allogeneic hematopoietic stem cell transplantation(alloHsCT)in two of Mexico's largest public and private *** To evaluate the impact of social determinants of health and their relationship with outcomes among allogeneic transplant recipients in *** In this retrospective cohort study,we included adolescents and adults≥16 years who received a matched sibling or haploidentical transplant from *** were selected without regard to their diagnosis and were sourced from both a private clinic and a public University Hospital in *** payment groups were compared:Out-of-pocket(OOP),private insurance,and a federal Universal healthcare program“seguro Popular”.Outcomes were compared between referred and institution-diagnosed patients,and between residents of Nuevo Leon and *** outcomes included overall survival(Os),categorized by residence,referral,and payment *** outcomes encompassed early mortality,event-free-survival,graft-versus-host-relapse-free survival,and non-relapse-mortality(NRM).statistical analyses employed appropriate tests,Kaplan-Meier method,and Cox proportional hazard regression *** software included sPss and R with tidycmprsk *** Our primary outcome was overall *** included 287 patients,n=164 who lived out of state(57.1%),and n=129 referred from another institution(44.9%).The most frequent payment source was OOP(n=139,48.4%),followed by private insurance(n=75,26.1%)and universal coverage(n=73,25.4%).No differences in Os,event-free-survival,NRM,or graft-versus-host-relapse-free survival were observed for patients dia

关键词： Hematopoietic cell transplant social determinants of health Geography Haploidentical Out-of-pocket financial toxicity survival Health services and outcomes Hematopoietic malignancy Aplastic anemia

A Preconditioned 3-DMulti-Region fast Multipole solver for seismic Wave Propagation in Complex Geometries

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Communications in Computational Physics 2012年第2期11卷 594-609页

作者： s.Chaillat j.f.semblat *** Georgia Tech College of ComputingAtlantaUSA Universite Paris Est IFSTTARParisFrance POems(CNRs-ENsTA-INRIA) Appl.Math.Dept.ENSTAParisFrance

The analysis of seismic wave propagation and amplification in complex geological structures requires efficient numerical *** this article,following up on recent studies devoted to the formulation,implementation and evaluation of 3-D single-and multi-region elastodynamic fast multipole boundary element methods(fM-BEMs),a simple preconditioning strategy is *** efficiency is demonstrated on both the single-andmulti-region versions using benchmark examples(scattering of plane waves by canyons and basins).finally,the preconditioned fM-BEM is applied to the scattering of plane seismic waves in an actual configuration(alpine basin of Grenoble,france),for which the high velocity contrast is seen to significantly affect the overall efficiency of the multi-region fM-BEM.

关键词： fast multipole method preconditioning strategy 3-D elastodynamics seismic wave propagation

Temperature and structure measurements of heavy-ion-heated diamond using in situ X-ray diagnostics

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Matter and Radiation at Extremes 2024年第4期9卷 80-89页

作者： j.Lutgert P.Hesselbach M.schorner V.Bagnoud R.Belikov P.Drechsel B.Heuser O.sHumphries P.Katrik B.Lindqvist C.Qu R.Redmer D.Riley G.schaumann s.schumacher A.Tauschwitz D.Varentsov K.Weyrich X.Yu B.Zielbauer Zs.Major P.Neumayer D.Kraus Institut fur Physik Universitat RostockAlbert-Einstein-Str.2318059 RostockGermany GsI Helmholtzzentrum fur schwerionenforschung Planckstr.164291 DarmstadtGermany Institut für Angewandte Physik Goethe-Universität Frankfurt am MainMax-von-Laue-Str.160438 Frankfurt am MainGermany Institut fur Geowissenschaften Goethe-Universitat Frankfurt am MainAltenhoferallee 160438 Frankfurt am MainGermany Helmholtz-Zentrum Dresden-Rossendorf Bautzner Landstr.40001328 DresdenGermany European XfEL GmbH Holzkoppel 422869 SchenefeldGermany Centre for Plasma Physics School of Mathematics and PhysicsQueen’s University BelfastUniversity RoadBelfast BT71NNUnited Kingdom Institut für Kernphysik Technische Universität DarmstadtSchlossgartenstr.964289 DarmstadtGermany state Key Laboratory of Nuclear Physics and Technology Institute of Heavy Ion PhysicsPeking UniversityBeijing 100871China Helmholtz Institut jena Frobelstieg 307743 JenaGermany

We present in situ measurements of spectrally resolved X-ray scattering and X-ray diffraction from monocrystalline diamond samples heatedwith an intense pulse of heavy *** this way,we determine the samples’heating dynamics and their microscopic and macroscopic structuralintegrity over a timespan of several *** the ratio of elastic to inelastic scattering with state-of-the-art density functionaltheory molecular dynamics simulations allows the inference of average temperatures around 1300 K,in agreement with predictions fromstopping power *** simultaneous diffraction measurements show no hints of any volumetric graphitization of the material,butdo indicate the onset of fracture in the diamond *** experiments pave the way for future studies at the facility for Antiproton andIon Research,where a substantially increased intensity of the heavy ion beam will be available.

关键词： heated intense structure

Assessing reservoir connectivity with pressure/rate surveillance data

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Petroleum science 2023年第2期20卷 1077-1086页

作者： G.f.j.Al-Khmaysawee Z.Reza C.s.Kabir Missouri University of sci.&Tech. RollaMOUSA University of Oklahoma NormanOKUSA Incendium Technologies Round RockTXUSA

Estimating reservoir connectivity is critical for assessing infill-drilling prospects and initiating fluid injection in enhanced oil recovery operations. several methods have appeared in the literature over decades to meet these business needs, given that all tools, including seismic imaging, have limitations. Besides imaging, geochemical fingerprinting constitutes a powerful tool to gauge the compartmentalization question. However, real-time pressure/rate surveillance data allows assessing interwell connectivity vis-à-vis the overall drainage *** study presents a simplified approach to using the reciprocal-productivity index (RPI) vs. the total-material-balance time (tTMB) plot. This tool exhibits the same slope for those wells in the same compartment beyond the start of the boundary-dominated flow (BDf) period. The wells showing different slopes imply that they are in separate drainage volumes. The early-time transient period remains muted to minimize confusion on this Cartesian plot. We validated the proposed tool's efficacy with 2D and 3D models with increased degrees of reservoir complexity, followed by the verification phase with four field examples. The use of other analytical tools complemented our findings.

关键词： Reservoir compartmentalization Reciprocal-productivity index Total material-balance time Analysis of boundary-dominated flow period