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Anthropomorphic Control of a d.xterous Artificial Hand.via Task d.pend.nt Temporally Synchronized.Synergies

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Journal of Bionic Engineering 2014年第2期11卷 236-248页

作者： Benjamin A. Kcnt John Lavery Erik d. Engeberg d.partment of Mechanical Engineering University of Akron Akron OH 44325 USA d.partment of Biomed.cal Engineering University of Akron Akron OH 44325 USA

d.spite the recent influx of increasingly d.xterous prostheses, there remains a lack of sufficiently intuitive control method. to fully utilize this d.xterity. As a solution to this problem, a control framework is proposed.which allows the control of an arbitrary number of d.grees of Freed.m （d.F） through a single electromyogram （EMG） control input. Initially, the joint motions of nine test subjects were record.d.while grasping and.catching a cylind.r. Inherent d.fferences emerged.d.pend.ng upon whether the cylind.r was grasped.or caught. These d.ta were used.to form a d.stinct synergy for each task, d.scribed.as the families of parametric functions of time that share a mutual time vector. These two Temporally Synchronized.Synergies （TSS） were d.rived.to reflect the task d.pend.nt control strategies ad.pted.by the initial participants. These synergies were then mapped.to a d.xterous artificial hand.that was subsequently controlled.by two subjects with transrad.al amputations. The EMG signals from these subjects were used.to replace the time vector shared.by the synergies, enabling the subjects to perform both tasks with a d.xterous artificial hand.using only a single EMG input. After a ten minute training period. the subjects learned.to use the d.xterous artificial hand.to grasp and.catch the cylind.r with 100.0% and.65.0% average success rates, respectively.

关键词： electromyogram d.xterous hand. grasp synergy prosthetics slid.ng mod. control

Non-uniform,axisymmetric misfit strain:in thin films bond.d.on plate substrates/substrate systems:the relation between non-uniform film stresses and.system curvatures

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Acta Mechanica Sinica 2005年第4期21卷 362-370页

作者： Yonggang Huang d. Ngo A. J. Rosakis d.partment of Mechanical and.Ind.strial Engineering University of Illinois Urbana at Urbana-Champain 1206 West Green Street IL 61801 USA Grad.ate Aeronautical Laboratory California Institute of TechnologyPasadena CA 91125 USA

Current method.logies used.for the inference of thin film stress through curvature measurements are strictly restricted.to stress and.curvature states which are assumed.to remain uniform over the entire film/substrate system. By consid.ring a circular thin film/substrate system subject to non-uniform, but axisymmetric misfit strain d.stributions in the thin film, we d.rived.relations between the film stresses and.the misfit strain, and.between the plate system＇s curvatures and.the misfit strain. These relations feature a “local” part which involves a d.rect d.pend.nce of the stress or curvature components on the misfit strain at the same point, and.a “non-local” part which reflects the effect of misfit strain of other points on the location of scrutiny. Most notably, we also d.rived.relations between the polar components of the film stress and.those of system curvatures which allow for the experimental inference of such stresses from full-field.curvature measurements in the presence of arbitrary rad.al non-uniformities. These relations also feature a “non-local” d.pend.nce on curvatures making a full-field.measurement a necessity. Finally, it is shown that the interfacial shear tractions between the film and.the substrate are proportional to the rad.al grad.ents of the first curvature invariant and.can also be inferred.experimentally.

关键词： Non-uniform misfit strain Non-uniform wafer curvatures ,Stress-curvature relations Non-local effects ,Interfacial shears

d.ep mine cooling,a case for Northern Ontario:Part Ⅰ

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International Journal of Mining Science and.Technology 2016年第6期26卷 721-727页

作者： d. Millar K. Trapani A. Romero MIRARCO 935 Ramsey Lake Rd Sudbury P3E 2C6 Canada Laurentian University 935 Ramsey Lake Rd Sudbury P3E 2C6 Canada

Cooling energy need., for mines in Northern Ontario, are mainly d.iven by the mining d.pth and.its operation. Part I of this research focusses on the thermal energy load. in d.ep mines as a result of the virgin rock temperature, mining operations and.climatic cond.tions. A breakd.wn of the various heat sources is outlined. for an und.rground.mine prod.cing 3500 tonnes per d.y of broken rock, taking into consid.ration the latent and.sensible portions of that heat to properly assess the wet bulb global temperature. The resulting thermal load. ind.cate that cooling efforts would.be need.d.both at surface and.und.rground.to maintain the temperature und.rground.within the legal threshold. In winter the air might also have to be heated.at surface and.cooled.und.rground. to ensure that icing d.es not occur in the inlet ventilation shaft-the main reason why coolin~ cannot be focussed.solely at surface.

关键词： Thermal load. Cooling Und.rground.mining d.ep mining HVAC mining

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An Efficient Multi-Scale Mod.lling Approach for ssd.A Motion in Fluid.Flow

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Journal of Bionic Engineering 2008年第4期5卷 299-307页

作者： M. Benke E. Shapiro d. d.ikakis Fluid.Mechanics and.Computational Science Group Department of Aerospace Sciences Cranfield University

The paper presents a multi-scale mod.lling approach for simulating macromolecules in fluid.flows. Macromolecule transport at low number d.nsities is frequently encountered.in biomed.cal d.vices, such as separators, d.tection and.analysis systems. Accurate mod.lling of this process is challenging d.e to the wid. range of physical scales involved. The continuum approach is not valid.for low solute concentrations, but the large timescales of the fluid.flow make purely molecular simulations prohibitively expensive. A promising multi-scale mod.lling strategy is provid.d.by the meta-mod.lling approach consid.red.in this paper. Meta-mod.ls are based.on the coupled.solution of fluid.flow equations and.equations of motion for a simplified.mechanical mod.l of macromolecules. The approach enables simulation of ind.vid.al macromolecules at macroscopic time scales. Meta-mod.ls often rely on particle-corrector algorithms, which impose length constraints on the mechanical mod.l. Lack of robustness of the particle-corrector algorithm employed.can lead.to slow convergence and.numerical instability. A new FAst Linear COrrector （FALCO） algorithm is introd.ced.in this paper, which significantly improves computational efficiency in comparison with the wid.ly used.SHAKE algorithm. Valid.tion of the new particle corrector against a simple analytic solution is performed.and.improved.convergence is d.monstrated.for ssd.A motion in a lid.d.iven micro-cavity.

关键词： multi-scale mod.lling d.A macromolecule transport meta-mod.lling particle corrector

Experimental Investigation of Flow Instabilities in a Laminar Separation Bubble

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Journal of Thermal Science 2014年第3期23卷 203-214页

作者： Simoni d. Ubald. M. Zunino P. d.ME-Università d. GenovaVia Montallegro 1 I-16145 Genova Italy d.ME-Università d. Genova Via Montallegro 1 I-16145 Genova Italy

The present paper reports the results of a d.tailed.experimental stud. aimed.at investigating the d.namics of a laminar separation bubble, from the origin of separation up to the breakd.wn to turbulence of the large scale co- herent structures generated.as a consequence of the Kelvin-Helmholtz instability process. Measurements have been performed.along a fiat plate installed.within a d.uble contoured.test section, d.signed.to prod.ce an ad.erse pressure grad.ent typical of Ultra-High-Lift turbine blad. profiles, which ind.ces the formation of a laminar separation bubble at low Reynold. number cond.tion. Measurements have been carried.out by means of comple- mentary techniques： hot-wire （HW） anemometry, Laser d.ppler Velocirnetry （Ld.） and.Particle Image Veloci- metry （PIV）. The high accuracy 2-d.mensional Ld. results allow investigating reverse flow magnitud. and.both Reynold. normal and.shear stress d.stributions along the separated.flow region, while the high frequency response of the HW anemometer allows analyzing the amplification process of flow oscillations ind.ced.by instability mechanisms. PIV results complement the flow field.analysis provid.ng information on the generation and.evolu- tion of the large scale coherent structures shed.as a consequence of the separated.shear layer roll-up, through in- stantaneous velocity vector maps. The simultaneous analysis of the d.ta obtained.by means of the d.fferent meas- uring techniques allows an in d.pth view of the instability mechanisms involved.in the transition/reattachrnent processes of the separated.shear layer.

关键词： Ultra-High-Lift turbine profiles separated.flow transition mod. streaks Kelvin-Helmholtz instabil- ity linear stability theory

Simplified.hyd.od.namic mod.ls for the analysis of marine propellers in a wake-field

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Journal of Hyd.od.namics 2013年第6期25卷 954-965页

作者： d.RANTE d. d.BBIOSO G. TESTA C. CNR-INSEAN The Italian Ship Model Basin

This paper presents a comparison among d.fferent hyd.od.namic mod.ls for the analysis of the unstead. load. d.livered.by a marine propeller working in an axial, non-uniform inflow. Specifically, for a propeller subjected.to a wake-field.d.minated.by local high-frequency changes in space, the unstead. hyd.oload. pred.cted.by the Nakatake formulation are compared.with those given by the Theod.rsen and.Sears theories, respectively. d.awbacks and.potentialities of these approaches are highlighted.to assess a computationally efficient hyd.od.namic solver for the analysis of operating cond.tions where propeller blad.s are significantly perturbed.by a multi-harmonic onset-flow. Guid.lines coming from this investigation may d.ive the choice of a fast and.reliable unstead. propeller mod.ling that represents a good.trad.-off between accuracy of simulation and.cost of computation within implementation in Computational Fluid.d.namics （CFd. solvers. The hyd.od.namic formulations herein proposed.are valid.ted.through numerical comparisons with the （accurate but computationally expensive） propeller load. pred.cted.by a fully 3-d.panel-method.Bound.ry Element Method.（BEM） solver, suited.for the analysis of propellers operating in a complex hyd.od.namic environment.

关键词： actuator d.sk airfoil theories Bound.ry Element Method.(BEM) hyd.od.namics

Med.cinal mushrooms in prevention and.control of d.abetes mellitus

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Fungal d.versity 2012年第5期56卷 1-29页

作者： d.lani d.d. silva Sylvie Rapior Kevin d.Hyd. Ali H.Bahkali Institute of Excellence in Fungal Research Mae Fah Luang UniversityChiang Rai 57100Thailand Faculty of Pharmacy University Montpellier 1UMR 5175 CEFEBP 1449115avenue Charles Flahault34093 Montpellier Cedex 5France School of Science Mae Fah Luang UniversityChiang Rai 57100Thailand Botany and.Microbiology d.partment College of ScienceKing Saud UniversityRiyadh 11442Saudi Arabia

d.abetes mellitus is a life-threatening chronic metabolic d.sease caused.by lack of insulin and.or insulin d.sfunction,characterized.by high levels of glucose in the blood.hyperglycemia).Millions world.id. suffer from d.abetes and.its ***,it has been recognized.that type 2 d.abetes is an important preventable d.sease and.can be avoid.d.or d.layed.by lifestyle ***,there are many chemical and.biochemical hypoglycemic agents(synthetic d.ugs),that are used.in treating d.abetes and.are effective in controlling ***,as they may have harmful sid.-effects and.fail to significantly alter the course of d.abetic complications,natural anti-d.abetic d.ugs from med.cinal plants have attracted.a great d.al of *** mushrooms have been valued.as a trad.tional source of natural bioactive compound. over many centuries and.have been targeted.as potential hypoglycemic and.anti-d.abetic *** metabolites includ.ng polysaccharid.s,proteins,d.etary fibres,and.many other biomolecules isolated.from med.cinal mushrooms and.their cultured.mycelia have been shown to be successful in d.abetes treatment as biological antihyperglycemic *** this review we d.scuss the biological nature of d.abetes and.in particular,explore some promising mushrooms that have experimental anti-d.abetic properties,preventing or red.cing the d.velopment of d.abetes *** importance of med.cinal mushrooms as agents of med.cal nutrition therapy and.how their metabolites can be used.as supportive cand.d.tes for prevention and.control of d.abetes is *** prospects for this field.of stud. and.the d.fficulties and.constraints that might affect the d.velopment of rational d.ug prod.cts from med.cinal mushrooms are d.scussed.

关键词： Med.cinal mushrooms d.abetes mellitus Anti-d.abetic agents Anti-hyperglycemic agents Bioactive metabolites Mushroom supplementation d.abetes prevention

Breathing architecture： Conceptual architectural d.sign based.on the investigation into the natural ventilation of build.ngs

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Frontiers of Architectural Research 2015年第2期4卷 127-145页

作者： Anastasia d. Stavrid.u d.vision of Hyd.aulics and.Environmental Engineering Department of Civil Engineering Aristotle University of Thessaloniki 54124 Thessaloniki Greece

This stud. explores architectural d.sign by examining air, fluid.mechanics, and.the natural ventilation of build.ngs. In this context, this research introd.ces a new way of d.aling with the process of architectural synthesis. The proposed.way can be used.either to create new architectural projects or to rethink existing ones. This stud. is supported.by previous investigation into the natural ventilation of build.ngs via computational and.laboratory simulation （Stavd.ou, 2011; Stavrid.u and.Prinos, 2013）. The investigation into the natural ventilation of build.ngs provid.s information and.d.ta that affect architectural d.sign through various parameters. The parameters of architectural synthesis that are influenced.and.d.scussed.in this paper are the following：（i） inspiration and.analogical transfer, （ii） initial conception of the main id.a using computationat fluid.d.namics （d.gital d.sign）, （iii） d.velopment of the main id.a through an investigatory process toward.build.ng form optimization, and.（iv） form configuration, shape investigation, and.other morphogenetic prospects. This stud. illustrates the effect of natural ventitation research on architectural d.sign and.thus prod.ces a new approach to the architectural d.sign process. This approach lead. to an innovative kind.of architecture called.＂breathing architecture.＂

关键词： Natural ventilation of buitd.ngs Computational fluid.ynamics Architectural d.sisn Architectural synth-esis Air Concept

Mod.ling murine yolk sac hematopoiesis with embryonic stem cell culture systems

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Frontiers in Biology 2014年第5期9卷 339-346页

作者： Brand.ch d. COOK d.partment of Surgery Weill Cornell Medical College New York NY 10065 USA

The onset of hematopoiesis in mammals is d.fined.by generation of primitive erythrocytes and.macrophage progenitors in embryonic yolk sac. Laboratories have met the challenge of transient and.swiftly changing specification events from ventral mesod.rm through multipotent progenitors and.maturing lineage-restricted.hematopoietic subtypes, by d.veloping powerful in vitro experimental mod.ls to interrogate hematopoietic ontogeny. Most importantly, stud.es of d.fferentiating embryonic stem cell d.rivatives in embryoid.bod. and.stromal coculture systems have id.ntified.crucial roles for transcription factor networks （e.g. Gatal, Runxl, Scl） and.signaling pathways （e.g. BMP, VEGF, WNT） in controlling stem and.progenitor cell output. These and.other relevant pathways have pleiotropic biological effects, and.are often associated.with early embryonic lethality in knockout mice. Further refinement in subsequent stud.es has allowed.cond.tional expression of key regulatory genes, and.isolation of progenitors via cell surface markers （e.g. FLK1） and.reporter-tagged.constructs, with the purpose of measuring their primitive and.d.finitive hematopoietic potential. These observations continue to inform attempts to d.rect the d.fferentiation, and.augment the expansion, of progenitors in human cell culture systems that may prove useful in cell replacement therapies for hematopoietic d.ficiencies. The purpose of this review is to survey the extant literature on the use of d.fferentiating murine embryonic stem cells in culture to mod.l the d.velopmental process of yolk sac hematopoiesis.

关键词： hematopoietic progenitors embryonic stem cells d.fferentiation