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Journal of Systems Science and Systems Engineering 2016年第2期25卷 254-268页

作者： A. Ertas M.w. Smith D. tate w.D. Lawson t.B. Baturalp Department of Mechanical Engineering Texas Tech University Lubbock TX USA 79410 Department of Industrial Design Xi 'an Jiaotong-Liverpool University Suzhou 215123 Jiangsu China Department of Civil Engineering Texas Tech University Lubbock TX USA 79410

this paper outlines a diagnostic approach to quantify the maintainability of a Commercial off-the-Shelf （COtS）-based system by analyzing the complexity of the deployment of the system components. Interpretive Structural Modeling （ISM） is used to demonstrate how ISM supports in identifying and understanding interdependencies among COtS components and how they affect the complexity of the maintenance of the COtS Based System （CBS）. through ISM analysis we have determined which components in the CBS contribute most significantly to the complexity of the system. with the ISM, architects, system integrators, and system maintainers can isolate the COtS products that cause the most complexity, and therefore cause the most effort to maintain, and take precautions to only change those products when necessary or during major maintenance efforts. the analysis also clearly shows the components that can be easily replaced or upgraded with very little impact on the rest of the system.

关键词： COtS Based System maintainability complexity Interpretive Structural Modeling

Achieving superior strength-ductility synergy in a heterostructured magnesium alloy via low-temperature extrusion and low-temperature annealing

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Journal of Materials Science & technology 2023年第32期163卷 32-44页

作者： H.wang D.t.Zhang C.Qiu w.w.Zhang D.L.Chen Guangdong Key Laboratory for Advanced Metallic Materials Processing and Forming National Engineering Research Center of Near-net-shape Forming for Metallic MaterialsSouth China University of TechnologyGuangzhou 510640China Department of Mechanical and Industrial Engineering Toronto Metropolitan University(formerly Ryerson University)350 Victoria StreetTorontoON M5B 2K3Canada

A low-alloyed Mg-1.2Zn-0.1Ca(wt.%)alloy was fabricated via low-temperature extrusion and annealing at 250℃for different times(10,30,and 90 min)to attain heterostructures with different fine-grained fractions,focusing on the effect of heterostructure on the mechanical *** dynamic recrystallization(RX)occurred during extrusion at 150℃,and a lamellar structure consisting of fine RX grains and coarse unRX grains was *** subsequent annealing promoted static RX in the as-extruded alloy,leading to an increased fine-grained fraction from 67%to 95%.Meanwhile,the co-segregation of Zn and Ca atoms impeded the migration of grain boundaries,thus achieving a fine grain size of 0.8–1.6μ*** sample annealed for 10 min with a fine-grained fraction of 73%and an average RX grain size of 0.9μm exhibited a superior combination of high yield strength(305 MPa)and good ductility(20%).In comparison,an excellent elongation of 30%was achieved in the alloy with a nearly fully-RXed microstructure and an average grain size of 1.6μm after 90 min annealing,despite a lower yield strength of 228 *** unRX grains,the hard orientation with(01–10)parallel to the extrusion direction and high-density dislocations made it more difficult to deform compared with the RX grains,thus producing hetero-deformation induced(HDI)*** fine grains and high-density dislocations,HDI strengthening is the key to achieving the superior mechanical properties of the low-alloyed Mg alloy.

关键词： Low-alloyed magnesium alloy Low-temperature extrusion Annealing Heterostructure Mechanical properties

A Review on the Management of Biliary Complications after Orthotopic Liver transplantation

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Journal of Clinical and translational Hepatology 2019年第1期7卷 61-71页

作者： Brian t.Moy John w.Birk Department of Medicine Division of Gastroenterology-HepatologyUniversity of Connecticut Health CenterFarmingtonCTUSA

Orthotopic liver transplantation is the definitive treatment for end-stage liver disease and hepatocellular *** complications are the most common complications seen after transplantation,with an incidence of 10-25%.these complications are seen both in deceased donor liver transplant and living donor liver *** treatment of biliary complications with endoscopic retrograde cholangiopancreatography(commonly known as ERCP)has become a mainstay in the management *** success rate has reached 80%in an experienced endoscopist's *** unsuccessful with ERCP,percutaneous transhepatic cholangiography can be an alternative *** recognition and treatment has been shown to improve morbidity and mortality in post-liver transplant *** focus of this review will be a learned discussion on the types,diagnosis,and treatment of biliary complications post-orthotopic liver transplantation.

关键词： Biliary tract complication Orthotropic liver transplantation Stricture Bile leak

Laser-induced fluorescence of macerals in relation to its hydrogen richness

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Chinese Science Bulletin 2000年第10期45卷 946-952页

作者： N.Sherwood R.w.t.wilkins CSIRO Division of Petroleum P.O.Box 136North Ryde 1670Australia

On the basis of results from conventional elemental analyses and a unique technique (FAMM? fluorescence alteration of multiple macerals), using a laser fluorescence microprobe, the fluorescence characteristics of various macerals are systematically related to hydrogen content. the amount of fluorescence from inertinite and vitrinite exponentially increases with H/C values. Although liptinite has high fluorescence and high H/C values, the relationship does not follow the same trend as defined for the other maceral groups. Because petroleum yields of a maceral mainly depend upon hydrogen richness, a correlation also exists between fluorescence, and gas to oil ratios from pyrolysis. Because individual organic entities are measured, the laser fluorescence microprobe has the benefit of accommodating heterogeneous organic matter in source rocks and enables determination of oil and gas yields of specific macerals.

关键词： laser fluorescence microprobe individual maceral fluorescence hydrogen richness oil and gas yields source rock assessment.

Metal-organic frameworks (MOFs) in aqueous batteries (ABs):unlocking potential through innovative materials design

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Science China Chemistry 2025年

作者： Bo Han Erhai Hu Bei-Er Jia Ziyang Liu Shuen tso Afriyanti Sumboja Ivandini t.Anggraningrum Anne Zulfia Syahrial Qingyu Yan SCARCE Laboratory Energy Research Institute NTU (ERIN) Nanyang Technological University School of Materials Science and Engineering Nanyang Technological University Material Science and Engineering Research Group Faculty of Mechanical and Aerospace Engineering Institut Teknologi Bandung Department of Chemistry University of Indonesia Metallurgical & Materials Engineering Department Fakultas Teknik Universitas Indonesia

Metal-organic frameworks (MOFs) represent a revolutionary class of materials in the field of energy storage,particularly for aqueous batteries (ABs).Distinguished by their large surface area,tuneable porosity,and adaptable chemical activity,MOFs offer significant advantages over conventional materials in battery *** article provides a thorough analysis of the crucial role that MOFs play in improving the efficiency of *** includes a concise review of the current research progress,emphasizing the fundamental processes by which MOFs enhance electrochemical ***,the review examines the synthesis and design strategies for the structure of MOFs to maximize ion transport,improve conductivity,and enhance *** structural advantages,chemical versatility,stability,durability and functionalization potential of MOFs are comprehensively ***,we explore the distinct advantages of MOFs in overcoming common challenges encountered in ABs,such as declining capacity,inadequate cycling stability,and limited energy *** paper also highlights the future research directions needed to fully harness their *** goal is to develop a fundamental understanding and stimulate further progress in the use of MOFs for advanced energy storage solutions.

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Influences of residual stress and micro-deformation on microstructures and mechanical properties for ti-6.5Al-3.5Mo-1.5Zr-0.3Si alloy produced by laser powder bed fusion

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Journal of Materials Science & technology 2021年第16期75卷 174-183页

作者： C.C.Zhang H.L.wei t.t.Liu L.Y.Jiang t.Yang w.H.Liao National Joint Engineering Research Center of NC Forming technology and Equipment School of Mechanical EngineeringNanjing University of Science and TechnologyNanjing 210094China

Laser powder bed fusion(LPBF)yields unique advantages during the fabrication of titanium *** the present work,ti-6.5 Al-3.5 Mo-1.5 Zr-0.3 Si alloy specimens with excellent mechanical performances were fabricated by *** as-built specimens displayed relatively high strength and ductility under modest volume energy densities(VEDs),whereas they manifested high strength with low ductility under high *** investigate the key reason of this phenomenon,the specimens were designed with two VEDs ranges of 60 J/mm^(3) and 85 J/mm^(3).Special attention was paid to the influences of residual stress and micro-deformation on microstructures and mechanical properties for the first *** results indicated that the residual stresses and relative density of the 60 J/mm^(3) range specimens were higher than that of the 85 J/mm3 range *** multiplication and dislocation movement promoted by the residual stress were hindered by the initialα’phase grain boundary(prior-α’GB),leading to the formation ofα’metastable *** mean tensile strength and elongation of the 60 J/mm^(3) range specimens were 1248.1 MPa and 12.3%,respectively,whereas the corresponding values for the 85 J/mm^(3) range specimens were 1405.3 MPa,5.0%,*** deformation,the strength and ductility of the specimens were first improved by lamellar structures generated from prior-α’phases,and then effectively enhanced by the interaction between the{10–12}twins and ***,pores significantly reduced the ductility;hence,high VED specimens with large twins and numerous large pores increased the strength and reduce the ductility.

关键词： Laser powder bed fusion ti-6.5Al-3.5Mo-1.5Zr-0.3Si alloy Residual stress twin Mechanical properties

tRANSIENt FLOwS AND PRESSURE wAVES IN PIPES

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Journal of Hydrodynamics 1995年第2期7卷 51-59页

作者： wang, Xiuqing Sun, J.G. Sha, w.t. Nuclear Industry Management Inst Beijing China

transient laminar flows and pressure-wave propagation in pipes, commonly called as water hammer, have been analyzed. A pressure-wave equation and a linearized velocity equation were derived from the equations of mass and momentum conservation. the waveform distortion due to viscous dissipation and elastic expansion of pipe wall was characterized by a dimensionless transmission number. the damping coefficients of pressure waves were found to be related to the roots of Bessel function. An exact solution of pressure-wave equation was obtained numerically. the relationship between the distortion of a traveling wave and transmission number was studied. the problem was also calculated with a general-purpose computer code, COMMIX, which solves exact mass conservation equation and Navier-Stokes equations. the computational results of the COMMIX code agreed well with the analytical solutions.

关键词： Computer simulation Differential equations Pipe flow water wave effects

Elastic-plastic behavior of a semicircular frame being pressed against a rigid plane

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Acta Mechanica Sinica 2008年第4期24卷 419-432页

作者： X.w.Zhang J.L.Yang t.X.Yu Institute of Solid Mechanics Beihang University Beijing 100083 China Department of Mechanical Engineering Hong Kong University of Science and Technology Kowloon Hong Kong China

As a simplified structural model, a semicircular frame is used to study the crashworthiness behavior of an aircraft fuselage. the quasi-static large elastic-plastic deformation of a semicircular frame in the process of its being pressed against a rigid ground is analyzed. First, based on the linear elastic assumption, the quasi-static large deformation contact process of the frame can be divided into three phases, i.e., point contact, line contact and post-buckling. By means of a shooting method, the relations between the displacement and contact force as well as the distribution of bending moment in the three phases are obtained. then, by assuming an elastic, perfectly-plastic moment-curvature relationship for the semi-circular frame, the contact process is analyzed in detail to reveal the plastic collapse mechanism, the traveling of plastic hinge and the force-displacement relationship. In order to verify the analysis, a preliminary experiment was conducted, in which two types of half rings with clamped ends were pressed by a rigid plate. In addition, a numerical simulation is also conducted by employing ABAQUS to analyze both rectangular cross-sectional beam and I-beam. Finally, the theoretical predictions are compared with the experimental results and numerical solutions, showing that the elastic-plastic analysis can predict the contact process very well.

关键词： Elastic-plastic·Large deformation ·Semicircular frame Contact ·traveling hinge

Scanning tunneling microscopy of buried dopants in silicon:images and their uncertainties

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npj Computational Materials 2022年第1期8卷 1727-1735页

作者： Piotr t.Różański Garnett w.Bryant MichałZieliński Institute of Physics Faculty of PhysicsAstronomy and InformaticsNicolaus Copernicus University in ToruńToruńPoland Nanoscale Device Characterization Division National Institute of Standards and TechnologyGaithersburgMD20899-8423USA

the ability to determine the locations of phosphorous dopants in silicon is crucial for the design,modelling,and analysis of atom-based nanoscale devices for future quantum computing ***,several papers showed that a metrology of scanning tunnelling microscopy(StM)imaging combined with atomistic tight-binding simulations could be used to determine coordinates of a dopant buried close to a Si *** identify effects which play a crucial role in the simulation of StM images and have to be precisely modelled for StM imaging of buried dopants and multi-dopant clusters to provide reliable position *** contrast to previous work,we demonstrate that a metrology combining StM imaging with tight-binding simulations may lead to pronounced uncertainty due to tip orbital model,effects of dangling bonds and choice of local atomic basis for the tight-binding *** work is still needed to obtain a reliable StM metrology of buried dopant position.

关键词： dopant buried metrology

ROBUStNESS OF EQUILIBRIA IN tHE GRAPH MODEL FOR CONFLICt RESOLUtION

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Journal of Systems Science and Systems Engineering 2015年第4期24卷 450-465页

作者： Yasser t.Matbouli D.Marc Kilgour Keith w.Hipel Department of Industrial Engineering King Abdulaziz University Department of Systems Design Engineering University of Waterloo Department of Mathematics Wilfrid Laurier University Centre for International Governance Innovation(CIGI)

A novel approach for assessing the robustness of an equilibrium in conflict resolution is presented. Roughly, an equilibrium is robust if it is resilient, or resistant to deviation. Robustness assessment is based on a new concept called Level of Freedom, which evaluates the relative freedom of a decision maker to escape an equilibrium. Resolutions of a conflict can be affected by changes in decision makers＇ preferences, which may destabilize an equilibrium, causing the conflict to evolve. Hence, a conflict may become long-term and thereby continue to evolve, even after reaching an equilibrium. the new robustness measure is used to rank equilibria based on robustness, to facilitate distinguishing equiiibria that are relatively sustainable. An absolutely robust equilibrium is a special case in which the level of freedom is at an absolute minimum for each individual stability definition.

关键词： Robustness equilibria level of freedom conflict evolution graph model