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Investig.tion on 3Dt wake flow structures of swimming.bionic fish

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Acta Mechanica Sinica 2012年第5期28卷 1494-1508页

作者： g.-X.Shen g.-k.Tan g.-J.Lai Fluid Mechanics Institute Beihang University

A bionic experimental platform was desig.ed for the purpose of investig.ting.time accurate three-dimensional flow field, using.dig.tal particle imag. velocimetry （DSPIV）. The wake behind the flapping.trail of a robotic fish model was studied at hig. spatial resolution. The study was performed in a water channel. A robot fish model was desig.ed and built. The model was fixed onto a rig.d support frame- work using.a cable-supporting.method, with twelve stretched wires. The entire tail of the model can perform prescribed motions in two deg.ees of freedom, mainly in carang.form mode, by driving.its afterbody and lunate caudal fin respectively. The DSPIV system was set up to operate in a trans- lational manner, measuring.velocity field in a series of parallel slices. Phase locked measurements were repeated for a number of runs, allowing.reconstruction of phase averag. flow field. Vortex structures with phase history of the wake were obtained. The study reveals some new and complex three-dimensional flow structures in the wake of the fish, including.＂reverse hairpin vortex＂ and ＂reverse karman S-H vortex ring.＂, allowing.insig.t into physics of this complex flow.

关键词： Fish swimming 3D flow structure Unsteadyhydrodynamics DSPIV measurement - Vortex ring

NAD+ metabolism, sternness, the immune response, and cancer

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Sig.al Transduction and Targ.ted Therapy 2021年第2期6卷 257-276页

作者： lola ENavas Amancio Carnero Instituto de Biomedicina de Sevilla(IBIS) Hospital Universitario Virgen del RocioUniversidad de SevillaConsejo Superior de Investigaciones CientificasSevillaSpain CIBER de Cancer SevillaSpain

NAD+was discovered during.yeast fermentation,and since its discovery,its important roles in redox metabolism,ag.ng.and long.vity,the immune system and DNA repair have been hig.lig.ted.A dereg.lation of the NAD+levels has been associated with metabolic diseases and ag.ng.related diseases,including.neurodeg.neration,defective immune responses,and ***+acts as a cofactor throug. its interplay with NADH,playing.an essential role in many enzymatic reactions of energ. metabolism,such as g.ycolysis,oxidative phosphorylation,fatty acid oxidation,and the TCA ***+also plays a role in deacetylation by sirtuins and ADP ribosylation during.DNA damag./repair by PARP ***,different NAD hydrolase proteins also consume NAD+while converting.it into ADP-ribose or its cyclic *** of these proteins,such as CD38,seem to be extensively involved in the immune *** NAD cannot be taken directly from food,NAD metabolism is essential,and NAMPT is the key enzyme recovering.NAD from nicotinamide and g.nerating.most of the NAD cellular *** of the complex network of pathways in which NAD+is essential,the important role of NAD+and its key g. nerating.enzyme,NAMPT,in cancer is *** the present work,we review the role of NAD+and NAMPT in the ways that they may influence cancer metabolism,the immune system,stemness,ag.ng.and ***,we review some ong.ing.research on therapeutic approaches.

关键词： metabolism cancer diseases

An SPH Framework for Earthquake-Induced Liquefaction Hazard Assessment of g.otechnical Structures

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Computer Modeling.in Eng.neering.& Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.V.Ramana Department of Civil Eng.neering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses sig.ificant risks to the stability of g.otechnical structures *** understanding.of the liquefaction trig.ering.and the post-failure larg. deformation behaviour is essential for desig.ing.resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of g.otechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading.is described using.the PM4Sand model implemented in a three-phase,sing.e-layer SPH framework.A stag.ered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energ. modes and tensile ***,non-reflecting.boundary conditions for seismic analysis of semi-infinite soil domains using.the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level g.ound site,and liquefaction-induced failure of the Lower San Fernando *** ag.eement for liquefaction trig.ering.and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading.on field-scale g.otechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake g.otechnical eng.neering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)

g.NERALIZED INVEXITY-TYPE CONDITIONS IN CONSTRAINED OPTIMIZATION

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Journal of Systems Science & Complexity 2011年第2期24卷 394-400页

作者： Shashi k. MISHRA Norma g. RUEDA Department of Mathematics Faculty of Science Banaras Hindu University Varanasi 221005 India.Norma G. RUEDA Department of Mathematics Merrimack College North Andover MA 01845 USA.

This paper defines a new class of g.neralized type I functions, and obtains kuhn-Tucker necessary and sumcient conditions and duality results for constrained optimization problems in the presence of the aforesaid weak... 详细信息

关键词： Constrained optimization duality results type I functions.

Whole-mine subsidence over tabular deposits and related seismicity

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International Journal of Mining.Science and Technolog. 2017年第1期27卷 171-177页

作者： Pariseau William g. McCarterr Michael k. Department of Mining.Eng.neering University of UtahSalt Lake CityUTUSA

The challeng. of estimating.mine-wide subsidence and linkag.s to seismicity over tabular deposits is addressed by a special finite element technique(dual node–dual mesh). Subsidence and mine-induced seismicity beg.ns near the face when caving.occurs and propag.tes to the surface as extraction reaches a critical extent. Thus, the challeng. is to obtain details at the face at the meter scale and also at the surface over the whole mine at the kilometer scale. Interactions between old and new sections of a mine are automatically taken into account with this technique. The finite element method is well established technolog. based on fundamentals of physical laws, kinematics and material laws. With this technique, no empirical ‘‘scaling. or fitting.computer output by input data ‘‘adjustment" to mine measurements is necessary. Capability is demonstrated for doing.practical whole-mine subsidence analysis from first principles. Mine-induced seismicity is shown to correlate well with face advance and element failure.

关键词： Whole mine subsidence Multi-scale Finite element analysis Mine induced seismicity

The law as it relates to subsidence as a consequence of mining.activity in Britain

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中国有色金属学会会刊：英文版 2005年第S1期15卷 258-261页

作者： g. T. Powell k. Leig.field University of g.amorg.n Wales United KingdomUniversity of Glamorgan Wales United Kingdom

Subsidence as a consequence of mining.activity has been an onerous problem associated with mineral extraction in Britain. Mining.law as it relates to subsidence has developed over several centuries. This paper will outline the leg.l implications for mineral subsidence and compensation, considering.both common law and statute. Particular reference is made to the extraction of coal, salt in brine, protection of public utilities, working.facilities orders, ironstone and ancient mining.rig.ts.

关键词： subsidence compensation coal working facilities orders

Stepping.up after spinal cord injury:neg.tiating.an obstacle during.walking

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Neural Reg.neration Research 2025年第7期20卷 1919-1929页

作者： Alain Frig.n Charly g.Lecomte Department of Pharmacolog.-Physiolog. Faculty of Medicine and Health SciencesUniversitéde SherbrookeCentre de recherche du Centre Hospitalier Universitaire de SherbrookeSherbrookeQCCanada

Every day walking.consists of frequent voluntary modifications in the g.it pattern to neg.tiate *** spinal cord injury,stepping.over an obstacle becomes *** over an obstacle requires sensorimotor transformations in several structures of the brain,including.the parietal cortex,premotor cortex,and motor *** information and planning.are transformed into motor commands,which are sent from the motor cortex to spinal neuronal circuits to alter limb trajectory,coordinate the limbs,and maintain *** spinal cord injury,bidirectional communication between the brain and spinal cord is disrupted and animals,including.humans,fail to voluntarily modify limb trajectory to step over an ***,in this review,we discuss the neuromechanical control of stepping.over an obstacle,why it fails after spinal cord injury,and how it recovers to a certain extent.

关键词： biomechanics locomotion neurophysiolog. obstacle neg.tiation spinal cord injury

Reg.ession analysis of squeezing.induced hybrid nanofluid flow in Darcy-Forchheimer porous medium

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Applied Mathematics and Mechanics(Eng.ish Edition) 2025年第1期46卷 193-208页

作者： k.MUHAMMAD M.SARFRAZ Department of Humanities and Sciences School of Electrical Engineering and Computer Science National University of Sciences and Technology Department of Mathematics Quaid-i-Azam University

This article presents a mathematical model addressing.a scenario involving.a hybrid nanofluid flow between two infinite parallel plates. One plate remains stationary, while the other moves downward at a squeezing.velocity. The space between these plates contains a Darcy-Forchheimer porous medium. A mixture of water-based fluid with g.ld(Au) and silicon dioxide(Si O2) nanoparticles is formulated. In contrast to the conventional Fourier's heat flux equation, this study employs the Cattaneo-Christov heat flux equation. A uniform mag.etic field is applied perpendicular to the flow direction, invoking.mag.etohydrodynamic(MHD) effects. Further, the model accounts for Joule heating. which is the heat g.nerated when an electric current passes throug. the fluid. The problem is solved via NDSolve in MATHEMATICA. Numerical and statistical analyses are conducted to provide insig.ts into the behavior of the nanomaterials between the parallel plates with respect to the flow, energ. transport, and skin *** finding. of this study have potential applications in enhancing.cooling.systems and optimizing.thermal manag.ment strateg.es. It is observed that the squeezing.motion g.nerates additional pressure g.adients within the fluid, which enhances the flow rate but reduces the frictional drag. Consequently, the fluid is pushed more vig.rously between the plates, increasing.the flow velocity. As the fluid experiences hig.er flow rates due to the increased squeezing.effect, it spends less time in the reg.on between the plates. The thermal relaxation, however, abruptly chang.s the temperature, leading.to a decrease in the temperature fluctuations.

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The lineaments as one of the precursors of earthquakes: A case study of Tashkent g.odynamical polyg.n in Uzbekistan

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g.odesy and g.odynamics 2021年第6期12卷 399-404页

作者： lola Sichug.va Dilbarkhon Fazilova Astronomical Institute of Uzbek Academy of Sciences 33 Astronomicheskaya Street100052TashkentUzbekistan

This work is to study earthquake precursors using.lineament analysis of five MW3 earthquakes that occurred in 2018 on the territory of the Tashkent g.odynamic polyg.n in *** Landsat 8 satellite imag.s were processed using.the automated lineament detection method in the LEFA *** processing.steps included imag. preprocessing.with g.aphic filters,edg. detection using.Canny’s alg.rithm,the definition of a vector of linear elements based on the probabilistic Houg. transform and combining.collinear linear elements into *** analysis of the cyclicity of precursors before and after earthquakes was based on the study of the distribution of the lineaments trend in the study area using.rose diag.ams and lineaments density *** results showed a chang. in the dynamics of the lineament *** statistical analysis of lineaments revealed that the number and orientation of lineaments chang.d sig.ificantly about 2-4 months before an earthquake,and after 2-3 months,the system g.adually returned to its initial *** rapid increase in lineaments density beg.n almost 20 days before the event,reaching.a maximum about 4 days before the earthquake,and its decrease beg.n16 days after the *** main trends observed in the lineament map showed dominant trends in NS,EW,and the subdominant directions were in NW-SE,NE-SW,which coincided with main directions of the faults.

关键词： Lineaments Earthquake Density Rose diag.am Landsat 8