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Exploring the mechanism of neural-function reconstruction by reinnervated nerves in targeted muscles

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第10期15卷 813-820页

作者： hui ZHOU Lin yang Feng-xia WU jian-ping HUANG Liang-qing ZHANG Ying-jian yang Guang-lin LI Institute of Biomedical and Health Engineering Shenzhen Institutes of Advanced TechnologyChinese Academy of Sciences Department of Rehabilitation Medicine Nanshan Hospital Affiliated to Guangdong Medical College Sino-Dutch Biomedical and Information Engineering School of Northeastern University

A lack of myoelectric sources after limb amputation is a critical challenge in the control of multifunctional motorized prostheses. To reconstruct myoelectric sources physiologically related to lost limbs, a newly proposed neural-function construc- tion method, targeted muscle reinnervation （TMR）, appears promising. Recent advances in the TMR technique suggest that TMR could provide additional motor command information for the control of multifimctional myoelectric prostheses. However, little is known about the nature of the physiological functional recovery of the reinnervated muscles. More understanding of the under- lying mechanism of TMR could help us fine tune the technique to maximize its capability to achieve a much higher performance in the control of multifunctional prostheses. In this study, rats were used as an animal model for TMR surgery involving transferring a median nerve into the pectoralis major, which served as the target muscle. Intramuscular myoelectric signals reconstructed following TMR were recorded by implanted wire electrodes and analyzed to explore the nature of the neural-fimction recon- struction achieved by reinnervation of targeted muscles. Our results showed that the active myoelectric signal reconstructed in the targeted muscle was acquired one week after TMR surgery, and its amplitude gradually became stronger over time. These pre- liminary results from rats may serve as a basis for exploring the mechanism of neural-function reconstruction by the TMR tech- nique in human subjects.

关键词： Neural function reconstruction Targeted muscle reinnervation Intramuscular myoelectric signal Myoelectri^prostheses /

Hierarchical porous carbon derived from animal bone as matric to encapsulated selenium for high performance Li-Se battery

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Rare Metals 2017年第5期36卷 434-441页

作者： Li-Sheng Xie Sheng-Xue Yu hui-Jun yang Jun yang jian-Lan Ni Jiu-Lin Wang Shanghai Electrochemical Energy Devices Research Center Department of Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China College of Environment and Chemistry Engineering Yanshan UniversityQinhuangdao 066004China Shanghai Using Yuan Environmental Engineering Co. LtdShanghai 201801China

Animal bone was employed as raw material to prepare hierarchical porous carbon by KOH activation. Rare metal selenium（Se） was encapsulated into hierarchical porous carbon successfully for the cathode material of Li–Se battery, achieving the transformation of waste into energy,protecting environment and reducing the spread of the disease. Animal bone porous carbon（ABPC） acquires a specific surface area of 1244.7903 m^2·g^-1 and a pore volume of 0.594184 cm^3·g^-1. The composite Se/ABPC with 51 wt%Se was tested as a novel cathode for Li–Se batteries. The results show that Se/ABPC exhibits high specific capacity,good cycling stability and current-rate performance; at 0.1C,the composite Se/ABPC delivers a high reversible capacity of 705 mAh·g^-1 in the second cycle and 591 mAh·g^-1 after 98 cycles. Even at the current density of 2.0C, it can still maintain at a reversible capacity of 485 mAh·g^-1. The excellent electrochemical properties benefit from the high electron conductivity and the carbon with unique hierarchical porous structure. ABPC can be a promising carbon matrix for Li–Se batteries.

关键词： Se/ABPC Animal bones High rate capability Li–Se battery Hierarchical porous structure

Temporal variations of CO_2 concentration near land surface and its response to meteorological variables in Heihe River Basin, northwest China

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Journal of Environmental Sciences 2006年第4期18卷 708-715页

作者： CHEN Ren-sheng KANG Er-si JI Xi-bin yang jian-ping ZHANG Zhi-hui yang Yong Laboratory of Watershed Hydrology and Ecology Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy ofSciences Lanzhou 730000 China

Atmospheric CO2 concentration （CC） near land surface and meteorological variables have been measured at four sites, named Yeniugou （alpine meadow and permafrost）, Xishui （mountainous forest）, Linze （oasis edge） and Ejina （lower desert）, respectively, in Heihe River Basin, northwest China. The results showed that, the half hourly CC at night was larger than in daytime, and the daily averaged CC was the largest in winter. The averaged CC of 932 d at the Linze was about 418 ppm, was about 366 ppm in the 762 d at the Ejina. In the same period from September 23 to November 9, 2004, the averaged CC was about 625,334, 436 and 353 ppm, at Yeniugou, Xishui, Linze and Ejina, respectively. The linear relationship between daily averaged CC and air temperature T was negative, between CC and relative humidity （RH） was positive. The linear CC-atmospheric pressure （A P） relationship was negative at the Linze and Yeniugou, was positive at the Ejina. The relationship between CC and global radiation R was exponent, and soil temperature Ts was negative linear, and soil water content was complex. The correlation between CC and wind speed was not existent. Using meteorological variables together to simulate CC, could give good results.

关键词： CO2 concentration meteorological variables Heihe River Basin

A joint optimization algorithm for focused energy delivery in precision electronic warfare

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Defence Technology（防务技术） 2022年第4期18卷 709-721页

作者： Zhong-ping yang Shu-ning yang Qing-song Zhou jian-yun Zhang Zhi-hui Li Zhong-rui Huang College of Electronic Engineering National University of Defense TechnologyHe FeiChina

Focused energy delivery(FED) is a technique that can precisely bring energy to the specific region,which arouses wide attention in precision electronic warfare(PREW).This paper first proposes a joint optimization model with respect to the locations of the array and the transmitted signals to improve the performance of *** the problem is nonconvex and NP-hard,particle swarm optimization(PSO) is adopted to solve the locations of the array,while designing the transmitted signals under a feasible array is considered as a unimodular quadratic program(UQP) subproblem to calculate the fitness criterion of *** the PSO-UQP framework established,two methods are presented for the UQP subproblem,which are more efficient and more accurate respectively than previous ***,a threshold value is set in the framework to determine which method to adopt to take full advantages of the methods ***,we obtain the maximum localization error that FED can tolerate,which is significant for implementing FED in *** results are provided to demonstrate the effectiveness of the joint optimization algorithm,and the correctness of the maximum localization error derived.

关键词： Focused energy delivery Localization error Particle swarm optimization Precision electronic warfare Unimodular quadratic program

The Synchrotron Emission of Jets with Transverse Velocity Discrepancy

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Chinese Journal of Astronomy and Astrophysics 2004年第4期4卷 311-319页

作者： hui-QuanLi jian-ChengWang LiXue NationalAstronomicalObservatories YunnanObservatoryChineseAcademyofSciencesKunming650011 UnitedLaboratoryforOpticalAstronomy ChineseAcademyofSciences GraduateSchooloftheChineseAcademyofSciences

It has been commonly accepted that the bulk velocity of extragalactic jets varies in all directions. We examined the synchrotron radiation of a jet with velocity structure in the direction perpendicular to its axis and found that the spectral energy distribution (SED) is not strongly influenced by this circumstance, that there is only a small increase in the emission intensity and almost no shift in the peak frequency. For objects with smaller inclined angles θ0 between the jet axis and the line of our sight, such as Blazars, the effect is more important. When θ0 exceeds a critical value there is no longer any change in the SED. To compare the bulk speed with different velocity structure, an equivalent speed β is defined which would reproduce the same spectral profile. There possibly exists a stress fμ(y) between layers of the outflow when the velocity is not the same in the jet.

关键词： galaxies: jets radiation mechanisms: non-thermal methods: numerical

A consistent projection-based SUPG/PSPG XFEM for incompressible two-phase flows

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Acta Mechanica Sinica 2012年第5期28卷 1309-1322页

作者： jian-hui Liao Zhuo Zhuang School of Aerospace Tsinghua University

In this paper, a consistent projection-based streamline upwind/pressure stabilizing Petrov-Galerkin （SUPG/PSPG） extended finite element method （XFEM） is presented to model incompressible immiscible two-phase flows. As the application of linear elements in SUPG/PSPG schemes gives rise to inconsistency in stabilization terms due to the inability to regenerate the diffusive term from viscous stresses, the numerical accuracy would deteriorate dramatically. To address this issue, projections of convection and pressure gradient terms are constructed and incorporated into the stabilization formulation in our method. This would substantially recover the consistency and free the practitioner from burdensome computations of most items in the residual. Moreover, the XFEM is employed to consider in a convenient way the fluid properties that have interfacial jumps leading to discontinuities in the velocity and pressure fields as well as the projections. A number of numerical examples are analyzed to demonstrate the complete recovery of consistency, the reproduction of interfacial discontinuities and the ability of the proposed projection-based SUPG/PSPG XFEM to model two-phase flows with open and closed interfaces.

关键词： Two-phase flow XFEM SUPG/PSPG algorithm Consistency Discontinuous projection

Fabrication of AI foam without thickening process through melt-foaming method

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Journal of Iron and Steel Research International 2018年第1期25卷 90-98页

作者： Dong-hui yang jian-qing Chen Lei Wang Jing-hua jiang Ai-bin Ma College of Mechanics and Materials Hohai UniversityNanjing 210098 Jiangsu China Suqian Research Institute of Hohai University Suqian 223814 Jiangsu China

By using calcium carbonate （CaCO3） powder as the blowing agent, Al foams with porosities of - 60 to 85% and pore size of - 1.5 mm were fabricated via melt-foaming method. Instead of adding a thickening agent to increase Al melt viscosity, a small amount of Mg ingot （5.0 wt%） was added first, and then A1 melt was foamed by adding calcium carbonate via the impellor stirring. The effect of Mg addition on the gas release behavior of calcium carbonate in the Al melt was investigated. The compression behavior of fabricated Al foams was examined. The results show that the blowing gas is possibly from the reaction between Mg and calcium carbonate, and this reaction can produce solid oxides with micrometer level size, which leads to increasing the Al melt viscosity and is beneficial for inhibiting pores coarsening. Besides, the micrometer level cracks in the cell walls make the strength of Al foam decrease.

关键词： Al foam Thickening agent Calcium carbonate Blowing gas Compression

Ductile fracture behavior of TA15 titanium alloy at elevated temperatures

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International Journal of Minerals,Metallurgy and Materials 2015年第10期22卷 1082-1091页

作者： Lei yang Bao-yu Wang jian-guo Lin hui-jun Zhao Wen-yu Ma School of Mechanical Engineering University of Science and Technology Beijing Department of Mechanical Engineering Imperial College LondonLondon SW7 2AZUK

To better understand the fracture behavior of TA15 titanium alloy during hot forming, three groups of experiments were conducted to investigate the influence of deformation temperature, strain rate, initial microstructure, and stress triaxiality on the fracture behavior of TA15 titanium alloy. The microstructure and fracture surface of the alloy were observed by scanning electronic microscopy to analyze the potential fracture mechanisms under the experimental deformation conditions. The experimental results indicate that the fracture strain increases with increasing deformation temperature, decreasing strain rate, and decreasing stress triaxiality. Fracture is mainly caused by the nucleation, growth, and coalescence of microvoids because of the breakdown of compatibility requirements at the α/β interface. In the equiaxed microstructure, the fracture strain decreases with decreasing volume fraction of the primary α-phase(αp) and increasing α/β-interface length. In the bimodal microstructure, the fracture strain is mainly affected by α-lamella width.

关键词： titanium alloys ductile fracture elevated temperat

Effect of Zr on undissolved phases and carbide precipitation in Ti microalloyed low-carbon steel

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Journal of Iron and Steel Research International 2019年第7期26卷 720-732页

作者： Peng-cheng Liu jian-chun Cao Shu-biao Yin Yin-hui yang Peng Gao Faculty of Materials Science and Engineering Kunming University of Science and Technology Kunming 650093 Yunnan China Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology Kunming 650093 Yunnan China

The undissolved phases and carbide precipitation in Ti and Ti-Zr microalloyed low-carbon steels were investigated by scanning electron microscopy, transmission electron microscopy and energy-dispersive X-ray spectrometry. At 1225℃, the replacement of Ti by Zr formed Zr2CS and (Zr, Ti)N (the Ti/Zr atomic ratio is 0.11) and reduced the consumption of Ti. At 925℃, it was identified that TiC phases were precipitated at first and Zr was incorporated into the TiC lattice in the subsequent precipitation process, which promoted the precipitation of titanium carbide. The calculation of the interaction coefficient between Ti, C, N and Zr showed that Zr reduced the activity of Ti and C and increased the activity of N in the iron matrix. Therefore, with the addition of Zr, the solubility of Ti was increased, and the consumption of Ti was reduced at high temperature in Ti microalloyed low-carbon steel. The thermodynamic calculation of carbide precipitation transformation showed that the replacement of Ti by Zr increased the nucleation driving force and the nucleation rate of titanium carbide, while the critical core size and the critical nuclear energy were reduced. As the holding time was extended, the Zr/ Ti atomic ratio increased and the size of the precipitates also increased. When the Zr/Ti atomic ratio reached a certain level, the size of the precipitates did not increase with further increase in atomic ratio. When the Zr/Ti atomic ratio in (Ti, Zr)C was 0.05-0.17,(Ti, Zr)C was the most stable carbide and the easiest to nucleate at 925℃. There was more of the (Ti, Zr)C phase than TiC at 925 ℃ after 50 and 100 s, and the time to complete the coarsening behavior of (Ti, Zr)C was shorter than that of TiC.

关键词： Ti-Zr microalloyed steel Undissolved phase Carbide precipitation Zirconium Thermodynamics