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Journal of Computational mathematics 2009年第2期27卷 338-347页

作者： erich Carelli Andrcas Prohl mathematisches Institut Universitt TübingenAuf der Morgenstelle 10D-72076 Tübingen

Projection methods are efficient operator-splitting schemes to approximate solutions of the incompressible Navier-Stokes equations. As a major drawback, they introduce spurious layers, both in space and time. In this work, we survey convergence results for higher order projection methods, in the presence of only strong solutions of the limiting problem; in particular, we highlight concomitant difficulties in the construction process of accurate higher order schemes, such as limited regularities of the limiting solution, and a lack of accurate initial data for the pressure. Computational experiments are included to compare the presented schemes, and illustrate the difficulties mentioned.

关键词： Incompressible Navier-Stokes equation Time discretization Projection method

Giant cavernous hemangioma of the liver with satellite nodules:Aspects on tumour/tissue interface:A case report

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World Journal of Hepatology 2023年第5期15卷 707-714页

作者： Anne Kristin Fischer Karl Tobias erich Beckurts Reinhard Büttner Uta Drebber Institute of Pathology University of CologneKöln 50937North Rhine WestphaliaGermany Visceral Surgery Severinsklösterchen Hospital CologneCologne 50678North Rhine WestphaliaGermany Institute of Pathology University Hospital of CologneCologne 50937North Rhine WestphaliaGermany

BACKGROUND Giant hepatic cavernous hemangioma with multiple satellite nodules is a rare subtype of hepatic cavernous hemangioma,the most common vascular liver *** report on a tumor with unusual histologic features:(1)Finger-like infiltration pattern;(2)lack of encapsulation;(3)blurred tumor/liver interface;and(4)massive satellitosis-referring to the article“Hepatic cavernous hemangioma:underrecognized associated histologic features”.CASE SUmmARY A 60-year-old man presented with increasing uncharacteristic abdominal discomfort and mildly elevated blood parameters of acute *** revealed an unclear,giant liver tumor of the left liver lobe.A massive vascular tumor with extensive satellitosis broadly infiltrating the adjacent liver parenchyma was resected via hemihepatectomy of segmentsⅡ/Ⅲ.Histopathological diagnosis was giant hepatic cavernous hemangioma with multiple satellite nodules,featuring unusual characteristics hardly portrayed in the ***,this particular morphology can explain the difficult pre-and perioperative diagnosis of a vascular liver tumor that is usually readily identifiable by modern imaging *** This case emphasizes the exact histological workup of tumor and tumor-induced parenchyma changes in radiologically unclassifiable liver tumors.

关键词： diagnosis hemangioma elevated

A combined method to model grain crushing with DEm

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Geoscience Frontiers 2020年第2期11卷 451-459页

作者： Jia Lin erich Bauer WeiWu Institute of Geotechnical Engineering University of Natural Resources and Life SciencesViennaAustria Institute of Applied mechanics Graz University of TechnologyGrazAustria

This paper presents a combined method to model grain crushing effects with discrete element *** method combines the two most commonly used concepts to model grain crushing in DEm,*** replacement method and the agglomerate method,so that it is both accurate and *** method can be easily *** performance is shown by several DEm simulations of biaxial *** with different crush-abilities are *** simulation results with and without grain crushing are compared and *** change of grain size distribution due to grain crushing is also investigated.

关键词： Grain crushing Discrete element method Granular material

Damage due to rolling in total knee replacement-The influence of tractive force

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Friction 2013年第2期1卷 178-185页

作者： markus AWImmER Lars BIRKEN Kay SELLENSCHLOH erich SCHNEIDER Section of Tribology Rush University Medical CenterChicagoIL 60612USA Section of Biomechanics Hamburg University of TechnologyHamburg21071Germany

The femoral condyles of a knee prosthesis articulate with a combination of rolling and sliding on the tibial polyethylene *** is known about potential polyethylene damage due to rolling *** rolling does not exclude the presence of tangential surface loads,this study sought to investigate the influence of tractive rolling on the wear of polyethylene.A“wheel-on-flat”apparatus,consisting of a metal wheel and a polyethylene flat,mimicked contact conditions present in total knee *** increasingly tractive force under conditions of pure rolling was *** was found that under rolling kinematics a tangential surface load of up to 17%of the normal load could be transferred through the *** damage was dependent on the amount of tractive force and appeared more severe with higher *** the region of highest tractive force,wear features were identified that resembled perpendicular ridges on surfaces of retrieved tibial polyethylene *** suggests that tractive rolling may be a relevant wear mode in total knee replacement.

关键词： polyethylene wear knee prosthesis tractive rolling

Immunotherapeutic approach on triple negative breast cancer: recent progress and predictors of response

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中华乳腺病杂志（电子版） 2022年第4期16卷 199-203页

作者： Louis Wing-Cheong Chow erich Ferdiansyah Lie UNImED medical Institute Hong KongChina Organisation for Oncology and Translational Research Hong KongChina

Clinical trials utilizing the immune checkpoint inhibitors,particularly the Impassion and KEYNOTE trials,have made it possible to understand how the immune checkpoint inhibitors can be used to treat patients with triple negative breast cancer(TNBC).Patient stratification based on simply PD-L1 positivity has now been shown to be insufficient and inaccurate as a predictor of response to the immune checkpoint inhibitors,and the role of the tumor microenvironment has become more *** article serves as a brief overview of the latest progress on the clinical trials as well as the potential predictors of response to immune checkpoint blockade.

关键词： Triple negative breast cancer Immunotherapy microenvironment

Training load characteristics and injury and illness risk identification in elite youth ski racing:A prospective study

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Journal of Sport and Health Science 2021年第2期10卷 230-236页

作者： Carolin Hildebrandt Renate Oberhoffer Christian Raschner erich muller Christian Fink Lisa Steidl-muller Department of Sport Science University of InnsbruckInnsbruck 6020Austria Department of Sport and Health Science Preventative PediatricsTechnical University of MunichMunich 80992Germany Department of Sport Science and Kinesiology University of SalzburgSalzburg 5400Austria GelenkpunktSports and Joint Surgery Innsbruck 6020Austria

Purpose:The study aimed to investigate the role of training load characteristics and injury and illness risk in youth ski ***:The training load characteristics as well as traumatic injuries,overuse injuries,and illnesses of 91 elite youth ski racers(age=12.1±1.3 years,mean±SD)were prospectively recorded over a period of 1 season by using a sport-specific online *** linear regression analyses were performed to monitor the influence of training load on injuries and *** in mean training load characteristics between preseason,in-season,and post-season were calculated using multivariate analyses of ***:Differences were discovered in the number of weekly training sessions(p=0.005)between pre-season(4.97±1.57)and post-season(3.24±0.71),in the mean training volume(p=0.022)between in-season(865.8±197.8 min)and post-season(497.0±225.5 min)and in the mean weekly training intensity(Index)(p=0.012)between in-season(11.7±1.8)and post-season(8.9±1.7).A total of 185 medical problems were reported(41 traumatic injuries,12 overuse injuries,and 132 illnesses).The weekly training volume and training intensity was not a significant risk factor for injuries(p>0.05).Training intensity was found to be a significant risk factor for illnesses in the same week(β=0.348;p=0.044;R^(2)=0.121)and training volume represents a risk factor for illnesses in the following week(β=0.397;p=0.027;R^(2)=0.157).Conclusion:A higher training intensity and volume were associated with increased illnesses,but not with a higher risk of *** training and ensuring appropriate progression of training load between weeks may decrease incidents of illness in-season.

关键词： Health problems Injury and illness prevention Training load Youth ski racing

Nonlinear silicon photonics on CmOS-compatible tellurium oxide

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Photonics Research 2020年第12期8卷 1904-1909页

作者： NEETESH SINGH HAmIDU m.mBONDE HENRY C.FRANKIS erich IPPEN JONATHAN D.B.BRADLEY FRANZ X.KÄRTNER Centre for Free Electron Laser Science(CFEL)-DESY and University of Hamburg 22607 HamburgGermany Research Laboratory of Electronics Massachusetts Institute of TechnologyCambridgeMassachusetts 02139USA Department of Engineering Physics McMaster UniversityHamiltonOntario L8S 4L7Canada

Silicon photonics is coming of age;however,it is still lacking a monolithic platform for optical sources and nonlinear functionalities prompting heterogeneous integration of different materials tailored to different *** we demonstrate tellurium oxide as a complementary metal oxide semiconductor silicon photonics platform for nonlinear functionalities,which is already becoming an established platform for sources and *** show broadband supercontinuum generation covering the entire telecom window and show for the first time to our knowledge third-harmonic generation in its integrated *** with the nowavailable lasers and amplifiers on integrated Te O_(2) this work paves the way for a monolithic TeO_(2)-based nonlinear silicon photonics platform.

关键词： oxide Together prompt

Numerical stress-deformation analysis of cut-off wall in clay-core rockfill dam on thick overburden

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Water Science and Engineering 2016年第3期9卷 219-226页

作者： Si-hong Liu Liu-jiang Wang Zi-jian Wang erich Bauer College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China Zhejiang Design Institute of Conservancy and Hydroelectric Power Hangzhou 310002China Institute of Applied mechanics Graz University of TechnologyGraz 8010Austria

The cut-off wall in a clay-core rockfill dam built on a thick overburden layer is subjected to a large compressive pressure under the action of the loads such as the dead weight of both the dam and the overburden layer, the frictional force induced by the differential settlement between the cut-off wall and surrounding soils, and the water pressure. Thus, reduction of the stress of the cut-off wall has become one of the main problems for consideration in engineering design. In this paper, numerical analysis of a core rockfill dam built on a thick overburden layer was conducted and some factors influencing the stress-strain behaviors of the cut-off wall were investigated. The factors include the improvement of the overburden layer, the modeling approach for interfacial contact between the cut-off wall and surrounding soils, the modulus of the cut-off wall concrete, and the connected pattern between the cut-off wall and the clay core. The result shows that improving the overburden layer,selecting plastic concrete with a low modulus and high strength, and optimizing the connection between the cut-off wall and the clay core of the dam are effective measures of reducing the deformations and compressive stresses of the cut-off wall. In addition, both the Goodman element and the mud-layer element are suitable for simulating the interfacial contact between the cut-off wall and surrounding soils.

关键词： Overburden layer Core rockfill dam Cut-off wall Numerical analysis Stress and deformation analysis

Calibration and performance of two different constitutive models for rockfill materials

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Water Science and Engineering 2016年第3期9卷 227-239页

作者： Lin-ke Li Zhan-jun Wang Si-hong Liu erich Bauer Institute of Applied mechanics Graz University of Technology Changjiang Institute of Survey PlanningDesign and Research College of Water Conservancy and Hydropower Engineering Hohai University

In this paper, two different concepts for the constitutive modeling of the mechanical behavior of creep-sensitive rockfill materials are presented. Specifically, the performance of an extended generalized plasticity model proposed by Wang is compared with a simplified version of the hypoplastic constitutive model for weathered rockfill materials proposed by Bauer. Both models can reflect the influence of the mean stress on the incremental stiffness, the peak friction angle, and the dilatancy angle. The so-called solid hardness defined for a continuum description and originally introduced by Bauer is embedded in both models. Hydrochemical, thermal, and mechanical weathering are usually caused by environmental changes and are taken into account in a phenomenological description with an irreversible and time-dependent degradation of the solid hardness. A degradation of the solid hardness is usually accompanied by creep deformation of the stressed rockfill material. It is shown that appropriate modeling of creep deformation requires at least a unified description of the interaction between the time-dependent process of degradation of the solid hardness and the stress state. In this context, the solid hardness can be understood as a key parameter for describing the evolution of the state of weathering of the rockfill material. Particular attention is also paid to the necessary procedure for determining the constitutive constants of the two different constitutive models. Finally, the performance of the two different constitutive models is demonstrated by comparing the results obtained from numerical simulations with experimental data from the creep-sensitive rockfill material.

关键词： Rockfill material Creep Generalized plasticity Hypoplasticity Constitutive model

Hypoplastic constitutive modeling of wetting deformation of weathered rockfill materials

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Frontiers of Structural and Civil Engineering 2010年第1期4卷 78-91页

作者： erich BAUER Zhongzhi FU Sihong LIU Institute of Applied mechanics Graz University of TechnologyGrazAustria Institute of Hydraulic Structures Hohai UniversityNanjing 210098China

The wetting deformation of weathered rockfill materials has been attracting growing attention from both engineers and *** importance of realistic predictions of wetting deformations for high earth and rockfill dams is a strong motivation to establish a suitable constitutive ***,the hypoplastic constitutive model by Gudehus and Bauer was extended by introducing solid hardness depending on the state of *** extended model takes into account the influence of the current density,the effective stress state,the rate of deformation,and the time dependent process of degradation of the solid *** the present paper,the performance of this model is evaluated by comparing numerical simulations with experiments obtained from a water sensitive rockfill *** particular,triaxial compression paths and creep deformation under deviatoric stress states are ***,the constitutive model proposed is used to study the influence of a degradation of the solid hardness on the long term behavior of a hypothetical fill dam.

关键词： rockfill dams weathered granular materials hypoplasticity solid hardness creep stress relaxation