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Comprehensive Euler/Lagrange modelling including particle erosion for confined gas-solid flows

Particuology 2024年第1期84卷 209-235页

作者： Guiherme A.novelletto Ricardo martin Sommerfeld Multiphase Flow Systems Institute of Process EngineeringOtto-von-Guericke-University MagdeburgHoher Weg 7b06120Halle(Saale)Germany

The present research aims to assess the capability of a comprehensive Euler/Lagrange approach for predicting gas-solid flows and the associated solid particle *** open-source code OpenFOAM®4.1 was used to carry out the numerical simulations,where the standard Lagrangian libraries were substantially extended to account for all necessary *** are tracked considering both translational and rotational motion as well as all relevant forces,such as gravity/buoyancy,drag and transverse lift due to shear and particle *** tracking time step was dynamically adapted ac-cording to the locally relevant time scales,which drastically reduces computational *** approaches are adopted to model particle turbulent dispersion,particle collisions with rough walls and particle-particle *** solid particle erosion models,available in the literature,were considered to estimate pipe bend *** study cases are provided to validate the adopted nu-merical approach and erosion models *** first case intends to evaluate the ability of the extended CFD code to predict the behaviour of gas-solid flows in pneumatic conveying *** goal is achieved by comparing the numerical results with the experimental data obtained by Huber(1997)and Huber and Sommerfeld(1994,1998)in a pneumatic conveying ***,the importance of considering inter-particle collisions and surface roughness for predicting particle velocity,mass flux and mean diameter distributions in gas-solid flows is *** second and third case intend to evaluate the ability of the erosion models in estimating bend erosion in diluted gas-solid *** erosion data obtained experimentally by Mazumder et al.(2008)and Solnordal et al.(2015)in very dilut pneumatic conveying systems is used for validating the numerical results,neglecting now inter-particle collisions and two-way *** a comprehensive analysis of the different influential properti

关键词： Pneumatic conveying Pipe bend numerical calculation(CFD) Euler/Lagrange approach Erosion models Wall roughness

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Physics-constrained graph modeling for building thermal dynamics

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Energy and AI 2024年第2期16卷 150-157页

作者： Ziyao Yang Amol D.Gaidhane Ján Drgoňa Vikas Chandan Mahantesh M.Halappanavar frank Liu Yu Cao School of Electrical Computer and Energy EngineeringArizona State UniversityTempeAZ 85287USA Pacific northwest national Laboratory RichlandWA 99354USA Oak Ridge national Laboratory Oak RidgeTN 37830USA

In this paper,we propose a graph model embedded with compact physical equations for modeling the thermal dynamics of *** principles of heat flow across various components in the building,such as walls and doors,fit the message-passing strategy used by Graph neural networks(Gnns).The proposed method is to represent the multi-zone building as a graph,in which only zones are considered as nodes,and any heat flow between zones is modeled as an edge based on prior knowledge of the building ***,the thermal dynamics of these components are described by compact models in the *** are further employed to train model parameters from collected *** model training,our proposed method enforces physical constraints(e.g.,zone sizes and connections)on model parameters and propagates the penalty in the loss function of *** constraints are essential to ensure model robustness and *** evaluate the effectiveness of the proposed modeling approach on a realistic dataset with multiple *** results demonstrate a satisfactory accuracy in the prediction of multi-zone ***,we illustrate that the new model can reliably learn hidden physical parameters with incomplete data.

关键词： Physics-constrained learning Graph neural networks Compact model Building thermal dynamics

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Standards and methods for dent assessment and failure prediction of pipelines:A critical review

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Petroleum Science 2022年第6期19卷 3029-3045页

作者： Jian Zhao Yun-Rong Lv Y.frank Cheng Dept.of Mechanical&Manufacturing Engineering University of CalgaryAlbertaT2N 1N4Canada Guangdong Provincial Engineering Technology Research Center of Petrochemical Corrosion and Safety Guangdong University of Petrochemical TechnologyMaomingGuangdongChina

Dent,a common mechanical damage on pipelines,is associated with a significant local plastic *** can cause pipeline failures,especially when they are combined with other types of defects such as gouges,fatigue,corrosion,and *** this work,a systematic review of various assessment methods and standards for pipeline dents,including the combination of a dent with other defects,is ***,the methods available today are not sufficiently accurate and reliable to assess pipeline dents,especially the dent-defect *** plain dents on pipelines,both the depthbased criterion and the strain-based criterion are commonly used in *** main problems include inaccuracy and *** a dent combined with other defects,the existing assessment techniques are not mature enough to give reliable *** experimental testing and numerical modeling through finite element(FE)analysis are capable of investigating the influence of dents and dent-defect combinations on burst failure pressure of the pipelines,although an approximation to the reality is still the main difficulty existing in the experimental testing and FE ***,relevant studies on assessment techniques for plain dents,a dent with fatigue and a dent with a single gouge have been common in *** combinations of a dent with corrosion or cracks have been rarely assessed due to complicated mechanisms involving a multi-physics coupling *** of novel assessment methods by integrating mechanical stress and strain,electrochemical reactions and steel metallurgy will be a key topic to accurately assess the dent-defect combinations for improved pipeline integrity.

关键词： Dents Pipelines Assessment techniques Burst failure pressure Dent-defect combinations

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Hybrid 2D–3D optical devices for integrated optics by direct laser writing

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Light(Science & Applications) 2014年第1期3卷 173-181页

作者： martin Schumann Tiemo Buckmann nico Gruhler martin Wegener Wolfram Pernice Institute of Applied Physics and DFG-Center for Functional nanostructures(CFn) Karlsruhe Institute of Technology(KIT)76131 KarlsruheGermany Institute of nanotechnology(InT) 76344 Eggenstein-LeopoldshafenGermany

Integrated optical chips have already been established for application in optical *** also offer interesting future perspectives for integrated quantum optics on a *** present,however,they are mostly fabricated using essentially planar fabrication approaches like electron-beam lithography or UV optical *** further design options would arise if one had complete fabrication freedom in regard to the third dimension normal to the chip without having to give up the virtues and the know-how of existing planar fabrication *** a step in this direction,we here use three-dimensional dip-in direct-laser-writing optical lithography to fabricate three-dimensional polymeric functional devices on pre-fabricated planar optical chips containing Si3n4 waveguides as well as grating couplers made by standard electron-beam *** first example is a polymeric dielectric rectangular-shaped waveguide which is connected to Si3n4 waveguides and that is adiabatically twisted along its axis to achieve geometrical rotation of linear polarization on the *** rotator’s broadband performance at around 1550 nm wavelength is verified by polarization-dependent grating *** polarization rotation on the optical chip cannot easily be achieved by other *** second example is a whispering-gallery-mode optical resonator connected to Si_(3)n_(4) waveguides on the chip via polymeric *** mechanically connecting the latter to the disk,we can control the coupling to the resonator and,at the same time,guarantee mechanical stability of the three-dimensional architecture on the chip.

关键词： direct laser writing integrated optics nanophotonic circuits polarization conversion

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The multi--intersection number of a graph

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西安电子科技大学学报 1990年第4期17卷 22-25页

作者： frank Harary Department of Computer Scicnce New Mexico State University USA

The intersection number, in (G), has been defined as the minimumcardinality of a set S which has n different subsets S_i such that each S_i can beassigned to the node v_i of G and nodes v_i, v_j are adjacent if and onlyif S_i∩S_j ≠0. We introduce the multiset intersection number min (G), defined similarly exceptthat multisets with elements in S may now be assigned to the nodes of G. Weprove that min (G) equals the smallest number ofcliques of G whose union is G.

关键词： Intersection graph number

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Spontaneous liver rupture following SARS-CoV-2 infection in late pregnancy:A case report

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World Journal of Clinical Cases 2022年第15期10卷 5042-5050页

作者： Radek Ambroz martin Stasek Ján Molnár Petr Spicka Dusan Klos Jozef Hambálek Daniela Skanderová Department of Surgery I University Hospital Olomouc and Faculty of Medicine and DentistryPalacky UniversityOlomouc 77900Czech Republic Department of Obstetrics and Gynecology University Hospital Olomouc and Faculty of Medicine and DentistryPalacky UniversityOlomouc 77900Czech Republic Department of Pathology University Hospital Olomouc and Faculty of Medicine and DentistryPalackýUniversityOlomouc 77900Czech Republic

BACKGROUnD Coronavirus disease-2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is characterized by systemic inflammatory response syndrome and ***-CoV-2 associated mortality ranges from 2%to 6%.Liver dysfunction was observed in 14%-53%of COVID-19 cases,especially in moderate severe ***,no cases of spontaneous hepatic rupture in pregnant women with SARS-CoV-2 have been *** SUMMARY A 32-year-old pregnant patient(gestational age:32 wk+4 d)without any remarkable medical history or long-term medication presented with ***,non-infectious,and pregnancy-related hepatopathies were *** onset of right subcostal pain with D-dimer and liver enzyme elevation was followed by shock with *** performing an emergency cesarean section,hemoperitoneum was observed,and the patient delivered a stillbirth.A 6-cm liver rupture at the edges of segments V and VI had occurred,which was sutured and ***-CoV-2 positivity on reverse transcriptionpolymerase chain reaction was *** revisions for intrahepatic hematoma with hemorrhagic shock and abdominal compartment syndrome were ***,the patient developed hemoptysis,which was treated using bronchoscopic therapy and non-invasive *** tissue biopsy revealed hemorrhagic foci and necrosis with an irregular centrilobular *** syndrome and autoimmune hepatitis were also ruled *** death was caused by acute intrauterine *** This case reveals that pregnant women with SARS-CoV-2 infection may be predisposed to liver parenchyma disease with liver rupture.

关键词： Liver rupture SARS-CoV-2 Pregnancy Abortion HELLP Case report

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Periodic surface functional group density on graphene via laserinduced substrate patterning at Si/SiO2 interface

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nano Research 2020年第9期13卷 2332-2339页

作者： Karolina A.Drogowska-Horna Inam Mirza Alvaro Rodriguez Petr Kovaricek Juraj Sladek Thibault J.-Y.Derrien Mindaugas Gedvilas Gediminas Raciukaitis Otakar frank nadezhda M.Bulgakova martin Kalbac J.Heyrovsky Institute of Physical Chemistry of the Czech Academy of Sciences Dolejskova 2155/318223 PragueCzech Republic HiLASE Centre Institute of Physics of the Czech Academy of SciencesZa Radnict 82825241 Dolni BrezanyCzech Republic Faculty of nuclear Sciences and Physical Engineering Czech Technical University in PragueBrehova 78/711519Czech Republic Center for Physical Sciences and Technology Savanoriu Ave.231LT-023000VilniusLithuania

Controlling the spatial distribution of functional groups on two-dimensional(2D)materials on a micrometer scale and below represents a fascinating opportunity to achieve anisotropic(opto)electronic properties of these *** patterns of covalent functionalization can lead to pericxJic potentials in the monolayer;however,creating such superstructures is very ***,we describe an original approach to the periodic functionalization of graphene induced by substrate patterning using a pulsed ***-induced periodic surface structures(LIPSS)are produced on silicon wafers with thermally-grown oxide *** irradiation conditions for the formation of UPSS confined at the SiO2/Si interface have been *** imprint their periodicity to the reactivity of the monolayer graphene placed on the substrate via modulation of its local doping *** method is clean,straightforward and scalable with high spatial resolution.

关键词： two-dimensional(2D)materials graphene functionalization laser-induced periodic surface structures(LIPSS) periodic patterns Raman spectroscopy atomic force microscopy(AFM)

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Impact of age on transcatheter aortic valve implantation outcomes：a comparison of patients aged≤ 80 years versus patients ＆gt; 80 years

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Journal of Geriatric Cardiology 2016年第1期13卷 31-36页

作者： frank van der Kley Philippe J van Rosendael Spyridon Katsanos Vasileios Kamperidis nina A Marsan Ioannis Karalis Arend de Weger Meindert Palmen Jeroen J Bax martin J Schalij Victoria Delgado Heart Lung Center Leiden University Medical Center Leiden the Netherlands

ObjectiveTo investigate the procedural outcomes and the long-term survival of patients undergoing transcatheter aortic valve implantation （TAVI） and compare study results of patients≤ 80 years and patients ＆gt; 80 years *** total of 240 patients treated with TAVI were divided into two groups according to age≤ 80 years （n = 105; 43.8%） and ＆gt; 80 years （n= 135; 56.2%）. The baseline characteristics and the pro-cedural outcomes were compared between these two groups of *** the exception of peripheral artery disease and hypercho-lesterolemia, which were more frequently observed in the older age group, baseline characteristics were comparable between groups. Complica-tion rates did not differ significantly between patients≤ 80 years and patients ＆gt; 80 years. There were no differences in 30-day mortality rates be-tween patients aged≤ 80 years and patients ＆gt; 80 years old （9.5%vs. 7.4%, respectively;P = 0.557）. After a median follow-up of 28 months （in-terquartile range： 16-42 months）, 50 （47.6%） patients aged≤ 80 years died compared to 57 （42%） deaths in the group of patients ＆gt; 80 years old （P= 0.404）.ConclusionThe results of the present single center study showed that age did not significantly impact the outcomes of TAVI.

关键词： Age Survival rate Transcatheter aortic valve implantation

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EXISTEnCE OF AREA MInIMIZInG TAnGEnT COnES OF InTEGRAL CURREnTS WITH PRESCRIBED MEAn CURVATURE

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Acta Mathematica Scientia 1995年第1期15卷 95-102页

作者： frank Duzaar(Institut fur Augewandte Mathematik der Universitat Bonn,Beringstr.4.D-53115 Bonn.martin Fuchs(Universitat des Saarlandes,Fachbereich Mathematik,D-66123 Saarbrucken) Institut für Angewandte Mathematik der Universität Bonn Beringstr. 4 D–53115 Bonn Universität des Saarlandes Fachbereich Mathematik D–66123 Saarbrücken

Given an integral M-currrent To in Rm+k and a tensor H of type(m.l)on Rn+k with values orthogonal to each of its arguments we proved in a previous peper[3]the sxistence of anintegral m-current T =γ(M,θ.ζ)with boundary T0 and mean curvature vector H by minimizing an appropriate functional on suitable subclasses of the set of all integral *** thes paperwe discuss the existence and structure of oriented tangent cones C of T at points x∈spt(T) spt(T),especially we show that C is locally mass minimizing.

关键词： integral currents,generalized mean curvature tangent cones

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Predicting the clothing insulation through machine learning algorithms:A comparative analysis and a practical approach

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Building Simulation 2024年第5期17卷 839-855页

作者： Pablo Aparicio-Ruiz Elena Barbadilla-martin Jose Guadix Jesus Munuzuri Grupo de Ingenieria de Organizacion Escuela Tecnica Superior de IngenieriaUniversidad de SevillaCamino de los Descubrimientos S/N41092SevilleSpain

Since indoor clothing insulation is a key element in thermal comfort models,the aim of the present study is proposing an approach for predicting it,which could assist the occupants of a building in terms of recommendations regarding their *** that,a systematic analysis of input variables is exposed,and 13 regression and 12 classification machine learning algorithms were developed and *** results are based on data from 3352 questionnaires and 21 input variables from a field study in mixed-mode office buildings in *** temperature at 6 a.m.,indoor air temperature,indoor relative humidity,comfort temperature and gender were the most relevant features for predicting clothing *** comparing machine learning algorithms,decision tree-based algorithms with Boosting techniques achieved the best *** proposed model provides an efficient method for forecasting the clothing insulation level and its application would entail optimising thermal comfort and energy efficiency.

关键词： clothing insulation simulation adaptive thermal comfort behavioural adaptive actions machine learning

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