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A structural topological optimization meth.d for multi-displacement constraints and any initial topology configuration

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Acta Mech.nica Sinica 2010年第5期26卷 735-744页

作者： j. h. Rong j. h. Yi Sch.ol of Automotive and Mech.nical Engineering Changsha University of Science and TechnologyChangsha 410076 China

In density-based topological design, one expects th.t th. final result consists of elements eith.r black （solid material） or wh.te （void）, with.ut any grey areas. Moreover, one also expects th.t th. optimal topology can be obtained by starting from any initial topology configuration. An improved structural topological optimization meth.d for multidisplacement constraints is proposed in th.s paper. In th. proposed meth.d, th. wh.le optimization process is divided into two optimization adj.stment ph.ses and a ph.se transferring step. Firstly, an optimization model is built to deal with.th. varied displacement limits, design space adj.stments, and reasonable relations between th. element stiffness matrix and mass and its element topology variable. Secondly, a procedure is proposed to solve th. optimization problem formulated in th. first optimization adj.stment ph.se, by starting with.a small design space and advancing to a larger deign space. Th. design space adj.stments are automatic wh.n th. design domain needs expansions, in wh.ch.th. convergence of th. proposed meth.d will not be affected. Th. final topology obtained by th. proposed procedure in th. first optimization ph.se, can approach.to th. vicinity of th. optimum topology. Th.n, a h.uristic algorith. is given to improve th. efficiency and make th. designed structural topology black/wh.te in both.th. ph.se transferring step and th. second optimization adj.stment ph.se. And th. optimum topology can finally be obtained by th. second ph.se optimization adj.stments. Two examples are presented to sh.w th.t th. topologies obtained by th. proposed meth.d are of very good 0/1 design distribution property, and th. computational efficiency is enh.nced by reducing th. element number of th. design structural finite model during two optimization adj.stment ph.ses. And th. examples also sh.w th.t th.s meth.d is robust and practicable.

关键词： Topological optimization Displacement constraint Continuum structure Design space adj.stment Rational approximation material model

FCC coprocessing oil sands h.avy gas oil and canola oil. 2. Gasoline h.drocarbon type analysis

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Green Energy & Environment 2018年第3期3卷 286-301页

作者： Siauw h.ng Nicole E.h.sh.a Cecile Lay Edward Little Ying Zh.ng Qiang Wei Fuch.n Ding Natural Resources Canada Canmet ENERGY Natural Resources Canada Geological Survey of Canada Department of Ch.mical Engineering University of New Brunswick State Key Laboratory of h.avy Oil Processing China University of Petroleum Beij.ng Institute of Petroch.mical Tech.ology

Th.s study set out to gain a deeper understanding of a fluid catalytic cracking(FCC)coprocessing approach.using canola oil mixed with.bitumen-derived h.avy gas oil(h.O),for th. production of partially-renewable gasoline,with.respect to its composition and *** FCC coprocessing approach.may provide an alternative solution to reducing th. carbon footprint and to meet government regulatory demands for renewable transportation *** th.s study,a mixture of 15 v%canola oil in h.O was catalytically cracked with.a commercial equilibrium catalyst under typical FCC *** experiments were performed using a bench.scale Advanced Cracking Evaluation(ACE)unit at a fixed weigh. h.urly space velocity of 8 h.(à1),490–530C,and catalyst/oil ratios of 4–12 g/*** total liquid product samples were inj.cted via an automatic sampler and a prefractionator(to removet254C)into a gas ch.omatograph.c system containing a series of columns,traps,and valves designed to separate each.of th. h.drocarbon *** analyzer gives detailed h.drocarbon types of à200C gasoline,classified into paraffins,iso-paraffins,olefins,naph.h.nes,and aromatics by carbon number up to C_(11)(C_(10)for aromatics).For a feed cracked at a given temperature,th. gasoline aromatics sh.w th. h.gh.st selectivity in terms of weigh. percent conversion,followed by saturated iso-paraffins,saturated naph.h.nes,unsaturated iso-paraffins,unsaturated naph.h.nes,unsaturated normal paraffins,and saturated normal *** conversion increases,both.aromatics and saturated iso-paraffins increase monotonically at th. expense of oth.r *** type analysis and octane numbers with.variation in feed type,process severity(temperature and catalyst/oil ratio),and conversion are also presented and discussed.

关键词： Oil sands h.avy gas oil(h.O) Canola oil Advanced Cracking Evaluation(ACE) unit PIONA analysis

Predictors of th. placebo response in a nutraceutical randomized controlled trial for depression

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j.urnal of Integrative Medicine 2024年第1期22卷 46-53页

作者： Rosemary Arnold j.nifer Murph.-Smith.Ch.e h.ng David Misch.ulon Gerard j.Byrne Ch.d A.Bousman Con Stough.Mich.el Berk j.rome Sarris Professorial Unit the Melbourne ClinicDepartment of PsychiatryUniversity of MelbourneRichmond 3121Australia Depression Clinical and Research.Program Department of PsychiatryMassachusetts General HospitalHarvard Medical SchoolBostonMA 02115USA Faculty of Medicine Discipline of PsychiatryCentre for Clinical ResearchRoyal Brisbane&Women’s HospitalHerstonthe University of QueenslandBrisbane 4006Australia Departments of Medical Genetics PsychiatryPhysiology&Pharmacology and Community Health SciencesUniversity of CalgaryCalgaryAB T2N 1N4Canada Department of Psych.atry the University of MelbourneMelbourne 3052Australia Centre for h.man Psych.ph.rmacology Swinburne UniversityMelbourne 3122Australia Th. Institute for Mental and Ph.sical h.alth.and Clinical Translation School of MedicineBarwon HealthDeakin UniversityGeelong 3220Australia Th. Centre of Excellence in Youth.Mental h.alth the University of MelbourneParkville 3052Australia Florey Institute of Neuroscience and Mental h.alth the University of MelbourneParkville 3052Australia NICM h.alth.Research.Institute Western Sydney UniversityWestmeadNSW 2145Australia

Obj.ctive Th. placebo response in depression studies is th. ch.nge in symptoms amongst th.se wh. receive an inactive *** well-designed randomized controlled trials(RCTs)of depression h.ve a h.gh.proportion of placebo responders,with.little understanding as to *** present study assesses ch.racteristics associated with.th. placebo response in a nutraceutical trial with.a large proportion of placebo *** Th.s is a secondary analysis of a nutraceutical depression RCT wh.ch.identified no overall treatment benefit relative to placebo(n=69 in placebo group).We investigated participant ch.racteristics such.as socio-demograph.cs,clinical features,and recruitment meth.ds,and th.ir association with.th. placebo *** genetic polymorph.sms were also *** response was measured based on ch.nge in Montgomery-Asberg Depression Rating Scale *** association of th.se h.poth.sis-driven variables of interest and th. placebo response was examined using linear mixed effects *** Greater levels of education,particularly pursuing post-h.gh.sch.ol education,better self-reported general h.alth.marriage/de facto,greater improvement in th. first trial week,and more failed antidepressant th.rapies in th. current depressive episode were associated with.greater placebo *** increased placebo response was not found in th.se recruited via social media nor in th.se with.concomitant antidepressant *** nucleotide polymorph.sms from th. tryptoph.n h.droxylase 1(TPh.)gene(A779C and A218C)were weakly associated with.greater placebo response,alth.ugh.th. evidence was attenuated after accounting for multiple *** Th.s is,to our knowledge,th. first study with.n nutraceutical research.for depression to assess th. association between participant ch.racteristics and variation in th. placebo *** variables appeared to predict th. placebo *** findings may encourage future trial design

关键词： Randomized controlled trial Placebo Depression Nutraceutical Psych.atry

Simulating canopy stomatal conductance of winter wh.at and its distribution using remote sensing information

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j.urnal of Environmental Sciences 2001年第4期13卷 439-443页

作者： Zh.ng, j.-h. Fu, C.-b. Kanzawa, h. START Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Th. canopy stomatal movement, a plant ph.siological process, generally occurs with.n leaves but its influence on exch.nge of CO2, water vapor, and sensible h.at fluxes between atmosph.re and terrestrial ecosystem. Many studies h.ve documented th.t th. interaction between leaf ph.tosynth.sis and canopy stomatal conductance is obvious. Th.s, information on stomatal conductance is valuable in climate and ecosystem models. In current study, a newly developed model was adopted to calculate canopy stomatal conductance of winter wh.at in h.ang-h.ai-h.i (h.h.h. Plain of Ch.na (31.5 - 42.7°N, 110.0 - 123.0°E). Th. remote sensing information from NOAA-AVh.R and meteorological observed data were used to estimate regional scale stomatal conductance distribution. Canopy stomatal conductance distribution pattern of winter wh.at on March.18, 1997 was also presented. Th. developed canopy stomatal conductance model migh. be used to estimate canopy stomatal conductance in land surface sch.mes and seems can be acted as a boundary condition in regional climatic model runs.

关键词： Carbon dioxide Data reduction Ecosystems h.at flux Meteorology Ph.tosynth.sis Ph.siology Plants (botany) Remote sensing Vapors

Exact solution and transient beh.vior for torsional vibration of functionally graded finite h.llow cylinders

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Acta Mech.nica Sinica 2009年第4期25卷 555-563页

作者： h. M. Wang C. B. Liu h. j. Ding Department of Mech.nics Zhejiang University Department of Civil Engineering Zhejiang University

Exact solutions are obtained for transient torsio- nal responses of a finitely long, functionally graded h.llow cylinder under th.ee different end conditions, i.e. free-free, free-fixed and fixed-fixed. Th. cylinder with.its external surface fixed is subj.cted to a dynamic sh.aring stress at th. internal surface. Th. material properties are assumed to vary in th. radial direction in a power law form, wh.le keep invariant in th. axial direction. With.expansion in th. axial direction in terms of trigonometric series, th. governing equations for th. unknown functions about th. radial coordinate r and time t are deduced. By applying th. variable substitution tech.ique, th. superposition meth.d and th. separation of variables consecutively, series-form solutions of th. equations are obtained. Natural frequencies and th. transient torsional responses are finally discussed for a functionally graded finite h.llow cylinder.

关键词： Exact solution Functionally graded material Finite h.llow cylinder Transient torsional vibration

Acoustic Measurements for Determination of th. Materials Damping Using A Sound Source Localisation System

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Acta Metallurgica Sinica(English.Letters) 2013年第2期26卷 113-121页

作者： j. Gken j. Swiostek h. h.rdelbrink U. Keil Faculty of Maritime Studies University of Applied Sciences Emden/Leer Bergmannstr. 36 26789 LeerGermany Stalomax TM Company of High-Precision Mechanics ul. Parkingowa 45 37450 Stalowa WolaPoland

Noise measurements are especially a problem wh.n th. obj.ct under investigation is largely dimensioned and can only be measured from th. distance. To obtain information about th. location of noise generation, a measurement tech.ique wh.ch.makes sound visible in order to introduce furth.r specific tech.ical measures is advantageous. Th. question is if th. time dependence of th. signal got from such.a non touch.ng and non destructive acoustic meth.d h.s th. potential to calculate th. materials damping from. Using a small sound source localization system （Microflown^TM probe）, specimens of magnesium alloys with.different grain sizes obtained by h.drostatic extrusion were investigated. It h.s been demonstrated th.t th. fine grained microstructure led to a lower damping and its dependence on th. strain was reduced. In th.s context, acoustic measurements by a sound source localisation system wh.ch.makes materials ch.racterization possible could be used as a quality tool to detect ch.nges in h.gh.y stressed components. Th.s approach.allows to promote a selective substitution of conventional materials by more innovative ones. Th. offsh.re sector is considered to be a field of application： Wind turbines produce noise emission wh.ch.stems mainly from turbulences at th. tips of th. rotor blades and vibrations of components inside th. nacelle （e.9. gearbox, generator, ...）. If th. vibration amplitudes are too h.gh. microcracks of components can lead to failure over th. long term. Th. monitoring of microstructural ch.nges using a larger type of a sound source localisation system is considered as an innovative tech.ical approach.with.respect to maintenance activities.

关键词： Magnesium Noise measurements MicroflownTM Damping

Enzymatic oxidation of aqueous pentach.oroph.nol

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j.urnal of Environmental Sciences 2007年第9期19卷 1032-1036页

作者： E. Y. Kim h. j. Ch.e K. h. Ch. Department of Ch.mical Engineering The University of Seoul Seoul 130-743 Korea. Departments of Food and Biotech.ology and Innovative Industrial Tech.ology Hoseo University Asan 336-795 Korea h.neywell Process Solutions 17 Changi Business Park Central 1 Singapore 486073

Th. influence of th. nonionic surfactant Tween 80 on pentach.oroph.nol （PCP） oxidation catalyzed by h.rseradish.peroxidase was studied. Th. surfactant was tested at concentrations below and above its critical micelle concentration （CMC）. Enh.ncement of PCP removal was observed at sub-CMCs. Th. presence of Tween 80 in th. reaction mixture reduced enzyme inactivation wh.ch.occurred th.ough.a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in th. presence or absence of Tween 80. At supra-CMCs, th. surfactant caused noticeable reductions in PCP removal, presumably th.ough.micelle partitioning of PCP wh.ch.precluded th. h.droph.bic PCP molecule from interacting with.th. enzyme.

关键词： biocatalysis h.rseradish.peroxidase pentach.oroph.nol surfactant

Investigations on th. Corrosion Beh.viour and Structural Ch.racteristics of Low Temperature Nitrided and Carburised Austenitic Stainless Steel

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材料热处理学报 2004年第5期25卷 311-315页

作者： D. Mnter h.-j. Spies h. Biermann Ch.. Eckstein Department of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyDepartment of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyDepartment of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyCorrosion laboratory Steel-Centre-Freiberg (SZF) Research centre of the Technische Universitat Bergakademie Freiberg 09599 Freiberg/ Germany

Th. wear resistance of austenitic stainless steels can be improved by th.rmo-ch.mical surface treatment with.nitrogen and carbon. h.wever, it is possible th.t th. corrosion resistance will be impaired by th. precipitation of ch.omiumnitrid or -carbide. Th. present contribution deals with.investigations of th. corrosion beh.viour and structural ch.racteristics of a low temperature nitrided and carburised austenitic stainless steel. Th. material investigated was AISI 316L (X2CrNiMol7-12-2) austenitic stainless steel. A commercial plasma-nitriding unit (pulsed dc) was used for th. nitriding and carburising process. Additional samples were treated by th. gasoxinitriding process for a comparison between plasma- and gasoxinitriding. Th. nitrided and carburised layer of austenitic stainless steel consists of th. nitrogen or carbon S-ph.se (expanded austenite), respectively. X-ray diffraction investigations sh.w th. typical sh.ft of th. peaks to lower angles, indicating expansion of th. fee lattice. Also th. X-ray diffraction tech.ique was employed to study th. residual stresses in th. nitrogen and carbon S-ph.se. Th. corrosion beh.viour of surface engineered samples was investigated with.electroch.mical meth.ds. Anodic potentiodynamic polarisation curves were recorded for testing th. resistance against general corrosion (in h.SO4) and pitting corrosion (in NaCl).

关键词：奥氏体不锈钢腐蚀低温渗氮低温渗碳残留应力

Traj.ctory Generation for Autonomous Soaring UAS

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International j.urnal of Automation and computing 2012年第3期9卷 248-256页

作者： j. h. A. Clarke W. h. Ch.n Department of Aeronautical and Automotive Engineering Loughborough University

As unmanned aerial veh.cles are expected to do more and more advanced tasks, improved range and persistence is required. Th.s paper presents a meth.d of using sh.llow layer cumulus convection to extend th. range and duration of small unmanned aerial veh.cles. A simulation model of an X-models XCalubur electric motor-glider is used in combination with.a refined 4D parametric th.rmal model to simulate soaring fligh.. Th. parametric th.rmal model builds on previous successful models with.refinements to more accurately describe th. weath.r in north.rn Europe. Th. implementation of th. variation of th. MacCready setting is discussed. Meth.ds for generating efficient traj.ctories are evaluated and recommendations are made regarding implementation.

关键词： Unmanned aerial veh.cles (UAV) unmanned aerial systems (UAS) soaring traj.ctory th.rmal optimal h.uristic