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PREDICTION OF PODDED PROPELLER CAVITATION USING AN UNSTEADY SURFACE PANEL METHOD

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Journal of Hydrodynamics 2008年第6期20卷 790-796页

作者： ye Jin-ming xiong Ying College of Naval Architecture and Power Naval University of Engineering Wuhan 430033 China

The unsteady sheet cavitation of podded propeller was predicted by using a surface panel method. The interaction between propeller and pod was treated with the iterative calculation of induced velocity potential, and the method of induced velocity potential can save a great deal of storage and computation time compared to the method of induced velocity. The induced velocity potential of unit singularity on every pod panel to every key blade panel and of unit singularity on every key blade panel and its wake panel to every pod panel were calculated when the key blade is at every angle position. Based on the wake model of the conventional single propeller, a new wake model of podded propeller was constructed. The propeller is analyzed only on the key blade in order to save computation time and memory space. The method can be used to calculate the hydrodynamics performance and cavitation of propeller in uniform and non-uniform inflows. It can give the unsteady force and cavitation shape of propeller. The propeller cavitation range determined by the present method agrees with the observation results of cavity image given in cavitation tunnel well, and this proves the practicability of the method.

关键词： pod propeller unsteady performance cavitation surface panel method

Enhancing optomechanical force sensing via precooling and quantum noise cancellation

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Science China(Physics,Mechanics & Astronomy) 2020年第1期63卷 44-54页

作者： Tesfay Gebremariam ye-xiong Zeng Mojtaba Mazaheri Chong Li Department of Physics Ar ba Minch UniversityAr ba Minch 21Ethiopia School of Physics Dalian University of TechnologyDalian 116024China Department of Basic Science Hamedan University of TechnologyHamedan 65169-1-3733Iran

We theoretically investigate optomechanical force sensing via precooling and quantum noise cancellation in two coupled cavity optomechanical systems. We show that force sensing based on the reduction of noise can be used to dramatically enhance the force sensing and that the precooling process can effectively improve the quantum noise cancellation. Specifically, we examine the effect of optomechanical cooling and noise reduction on the spectral density of the noise of the force measurement; these processes can significantly enhance the performance of optomechanical force sensing, and setting up the system in the resolved sideband regime can lead to an optimization of the cooling processes in a hybrid system. Such a scheme serves as a promising platform for quantum back-action-evading measurements of the motion and a framework for an optomechanical force sensor.

关键词： hybrid optomechanical system coherent quantum noise cancellation force sensing

Remodeling dendritic spines for treatment of traumatic brain injury

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Neural Regeneration Research 2019年第9期14卷 1477-1480页

作者： ye xiong Asim Mahmood Michael Chopp Department of Neurosurgery Henry Ford HospitalDetroitMIUSA Department of Neurology Henry Ford HospitalDetroitMIUSA Department of Physics Oakland UniversityRochesterMIUSA

Traumatic brain injury is an important global public health *** brain injury not only causes neural cell death,but also induces dendritic spine *** neurons from cell death in the injured brain may exhibit dendrite damage,dendritic spine degeneration,mature spine loss,synapse loss,and impairment of *** degeneration and synapse loss may significantly contribute to functional impairments and neurological disorders following traumatic brain *** function of the nervous system depends on maintenance of the functionally intact synaptic connections between the presynaptic and postsynaptic spines from neurons and their target *** synaptic plasticity,the numbers and shapes of dendritic spines undergo dynamic *** of spine heads and the formation and stabilization of new spines are associated with long-term potentiation,while spine shrinkage and retraction are associated with long-term *** of memory is associated with remodeling and growth of preexisting synapses and the formation of new *** date,there is no effective treatment to prevent dendritic degeneration and synapse *** review outlines the current data related to treatments targeting dendritic spines that propose to enhance spine remodeling and improve functional recovery after traumatic brain *** mechanisms underlying proposed beneficial effects of therapy targeting dendritic spines remain elusive,possibly including blocking activation of Cofilin induced by beta amyloid,Ras activation,and inhibition of GSK-3 signaling *** understanding of the molecular and cellular mechanisms underlying synaptic degeneration/loss following traumatic brain injury will advance the understanding of the pathophysiology induced by traumatic brain injury and may lead to the development of novel treatments for traumatic brain injury.

关键词： traumatic brain injury dendritic spines synaptic plasticity spinogenic agents treatment spine remodeling memory functional recovery

Mesenchymal stem cell-derived extracellular vesicles as a cell-free therapy for traumatic brain injury via neuroprotection and neurorestoration

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Neural Regeneration Research 2024年第1期19卷 49-54页

Traumatic brain injury is a serious and complex neurological condition that affects millions of people *** significant advancements in the field of medicine,effective treatments for traumatic brain injury remain ***,extracellular vesicles released from mesenchymal stem/stromal cells have emerged as a promising novel therapy for traumatic brain *** vesicles are small membrane-bound vesicles that are naturally released by cells,including those in the brain,and can be engineered to contain therapeutic cargo,such as anti-inflammatory molecules,growth factors,and *** administered intravenously,extra cellular vesicles can cross the blood-brain barrier and deliver their cargos to the site of injury,where they can be taken up by recipient cells and modulate the inflammatory response,promote neuroregeneration,and improve functional *** preclinical studies,extracellular vesicle-based therapies have shown promising results in promoting recove ry after traumatic brain injury,including reducing neuronal damage,improving cognitive function,and enhancing motor *** further research is needed to establish the safety and efficacy of extra cellular vesicle-based therapies in humans,extra cellular vesicles represent a promising novel approach for the treatment of traumatic brain *** this review,we summarize mesenchymal ste m/stromal cell-de rived extracellular vesicles as a cell-free therapy for traumatic brain injury via neuroprotection and neurorestoration and brainderived extracellular vesicles as potential biofluid biomarkers in small and large animal models of traumatic brain injury.

关键词： biomarkers extracellular vesicles functional outcome mesenchymal stem/stromal cells neuroinflammation neuroplasticity neuroprotection traumatic brain injury

Emerging potential of exosomes for treatment of traumatic brain injury

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Neural Regeneration Research 2017年第1期12卷 19-22页

Traumatic brain injury（TBI） is one of the major causes of death and disability *** effective treatment has been identified from clinical *** evidence exists that treatment with mesenchymal stem cells（MSCs） exerts a substantial therapeutic effect after experimental brain *** addition to their soluble factors,therapeutic effects of MSCs may be attributed to their generation and release of *** are endosomal origin small-membrane nano-sized vesicles generated by almost all cell *** play a pivotal role in intercellular *** delivery of MSC-derived exosomes improves functional recovery and promotes neuroplasticity in rats after *** effects of exosomes derive from the exosome content,especially micro RNAs（mi RNAs）.mi RNAs are small non-coding regulatory RNAs and play an important role in posttranscriptional regulation of *** with their parent cells,exosomes are more stable and can cross the blood-brain *** have reduced the safety risks inherent in administering viable cells such as the risk of occlusion in microvasculature or unregulated growth of transplanted *** a cell-free exosome-based therapy may open up a novel approach to enhancing multifaceted aspects of neuroplasticity and to amplifying neurological recovery,potentially for a variety of neural injuries and neurodegenerative *** review discusses the most recent knowledge of exosome therapies for TBI,their associated challenges and opportunities.

关键词： traumatic brain injury exosomes microRNAs mesenchymal stem cells treatment neuroplasticity cell therapy

Mechanical properties and microstructure of an α+β titanium alloy with high strength and fracture toughness

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Rare Metals 2009年第4期28卷 346-349页

作者： YU Yang HUI Songxiao ye Wenjun xiong Baiqing State Key Laboratory for Fabrication and Processing of Nonferrous Metals General Research Institute for Nonferrous Metals Beijing 100088 China

The Ti-Al-Sn-Zr-Cr-Mo-V-Si （Ti-62A） alloy, an alpha-beta alloy with high strength and fracture toughness, is currently used as an advanced structural material in aerospace and non-aerospace applications. Thermo-mechanical processes can be used to optimize the relationship between its strength and fracture toughness. A Ti-62A alloy bar can be machined through a transus β-forged plus α＋β solution treated and aged specimen with a lamellar alpha microstructure. The effects of heat treatment on the mechanical properties were discussed. Heat treatment provided a practical balance of strength, fracture toughness, and fatigue crack growth resistance. A comparison of the Ti-62A alloy with the Ti-62222S alloy under the same thermo-mechanical processing conditions showed that their properties are at the same level.

关键词： titanium alloys mechanical properties strength toughness fatigue crack growth rate

Fabrication and analysis of nano-structured thermal spraying feeds

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 83-87页

作者： ye xiong-lin MA Shi-ning LI Chang-qing National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China

A kind of thermal spray nanostructured Al2O3 and TiO2 feeds fabricating technology was *** nanogranules prepared by spray drying were heat treated in order to be dense, and there were two sintering technologies used, i.e. high temperature electric furnace sintering and high velocity flame sintering, respectively. The results indicate feeds phase components using high temperature electric furnace sintering at 1 200 ℃,1 300 ℃ and 1 400 ℃ do not change, and grain sizes of nano-Al2O3 and TiO2 grow little at 1 200 ℃ and 1 300 ℃,while grain sizes of nano-Al2O3 and TiO2 grow obviously, and the grain size of nano-TiO2 is larger than 100 nm at 1400 ℃. Phase components of the feeds using high velocity flame sintering change, where α-Al2O3 changes to γ-Al2O3 and rutile TiO2 changes to brookite TiO2, though grain size of nano-Al2O3 does not grow and is less than 100 nm because cooling velocity is too quick. Compared with these two heat treatment technology, the technology using electric furnace to treat nanostructured Al2O3 and TiO2 feeds is more suitable.

关键词： nanostructured feeds thermal spray heat treatment

NUMERICAL PREDICTION OF BLADE FREQUENCY NOISE OF CAVITATING PROPELLER

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Journal of Hydrodynamics 2012年第3期24卷 371-377页

作者： ye Jin-ming xiong Ying LI Fang WANG Zhan-zhi College of Naval Architecture and Power Naval University of Engineering Wuhan 430033 China

The blade frequency noise of a cavitating propeller in a uniform flow is analyzed in the time domain. The unsteady loading （of a dipole source） and the sheet cavity volume （of a monopole source） on the propeller surface are calculated by a potential-based surface panel method. Then the time-dependent pressure and the cavity volume data are used as the input for the Fowcs Williams-Hawkings formulation to predict the acoustics pressure. The integration of the noise source is performed over the true blade surface rather than the ideal blade surface without thickness. The noise characteristics of the cavitating propeller are discussed. With the sheet cavitation, the thickness （cavitation） noise is larger than the loading noise and is the dominant noise source. The noise directivity is not as clear as that of the noise under a non-cavitation condition. The cavitation noise is attenuated more slowly than the non-cavitation noise.

关键词： propeller surface panel method cavitation noise time domain

Big data analytics and business analytics

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Journal of Management Analytics 2015年第1期2卷 1-21页

作者： Lian Duan ye xiong College of Computing Sciences New Jersey Institute of TechnologyNewarkNJ 07102USA

Over the past few decades,with the development of automatic identification,data capture and storage technologies,people generate data much faster and collect data much bigger than ever before in business,science,engineering,education and other *** data has emerged as an important area of study for both practitioners and *** has huge impacts on data-related *** this paper,we identify the key issues related to big data analytics and then investigate its applications specifically related to business problems.

关键词： big data analytics business analytics management analytics business intelligence marketing analytics