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On hp refinements of independent cover numerical manifold method——some strategies and observations

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Science China(Technological Sciences) 2023年第5期66卷 1335-1351页

作者： ZHAng ning ZHEng Hong LI Xu wu WenAn School of Civil Engineering Qinghai UniversityQinghai810016China Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing100081China Key Laboratory of Urban Underground Engineering of Ministry of Education Beijing Jiaotong UniversityBeijing100091China

In this paper,strategies are provided for a powerful numerical manifold method(NMM)with h and p refinement in analyses of elasticity and *** new NMM is based on the concept of the independent cover,which gets rid of NMM's important defect of rank deficiency when using higher-order local approximation *** techniques are *** terms of mesh generation,a relationship between the quadtree structure and the mathematical mesh is established to allow a robust *** to the condition number,a scaling based on the physical patch is much better than the classical scaling based on the mathematical patch;an overlapping width of 1%–10%can ensure a good condition number for 2nd,3rd,and 4th order local approximation functions;the small element issue can be overcome after the local approximation on small patch is replaced by that on a regular *** numerical accuracy,local approximation using complete polynomials is necessary for the optimal convergence *** issues that may damage the convergence rate should be *** first is to approximate the curved boundary of a higher-order element by overly few straight lines,and the second is excessive overlapping ***,several refinement strategies are verified by numerical examples.

关键词： independent cover numerical manifold method hp refinement partition of unity higher order element condition number

Modeling and analysis of magnetic spring enhanced lever-type electromagnetic energy harvesters

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Applied Mathematics and Mechanics(English Edition) 2022年第5期43卷 743-760页

作者： ning yU Xiangyi FEI Chuanyu wu Bo yAN School of Mechanical Engineering&Automation Zhejiang Sci-Tech UniversityHangzhou 310018China

This study presents a novel enhanced monostable lever-type electromagnetic energy harvester(L-EEH).According to the positions of the coil and the lever pivot,four configurations are discussed to realize a better harvesting performance of the *** the basis of establishing the theoretical model of the L-EEH,the corresponding analytical solutions can be obtained by apply.ng the harmonic balance *** effects of the nonlinear coefficient,the lever ratio,the mass ratio,and the circuit parameters on the energy harvesting performance of L-EEHs are analyzed and *** numerical and experimental efforts are carried out to verify the theoretical model and the energy harvesting *** results demonstrate that the maximum output voltage can be achieved with an appropriate lever ***,the L-EEH possesses a considerable energy harvesting performance under a smaller lever ratio compared with the other three *** output power can also be improved by adjusting the tip mass of the *** proposed L-EEH has a considerable operating bandwidth and an output power,which can reach 146.6 mW under the excitation amplitude of 0.3 g.

关键词： electromagnetic energy harvesting monostable nonlinear vibration lever harvester

Fabrication of Carbon Nanotubes and Rare Earth Pr Reinforced AZ91 Composites by Powder Metallurgy

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Chinese Journal of Mechanical Engineering 2021年第2期34卷 213-222页

作者： ning Li Hong yan Qingjie wu Zeyu Cao School of Mechanical Electrical Engineering Nanchang UniversityNanchang 330031China School of Aviation Manufacturing Engineering Nanchang Hangkong UniversityNanchang 330069China

It can be known from a large number of research results that improving the dispersibility of CNTs can effectively optimize the mechanical properties of the corresponding metal matrix ***,the crucial issue of increasing the bonding of CNTs and the matrix is still *** this paper,a novel method was developed to increase interfacial bonding strength by coating titanium oxide(TiO2)on the surface of *** rare earth Pr and TiO2@CNTs-reinforced AZ91matrix composites were successfully fabricated by powder *** press sintering and hot extrusion of the milled powder was *** hot extrusion,the influence of TiO2@CNTs on the microstruc-ture and mechanical properties of the composites were *** results showed that the coating process can improve the distribution of CNTs in Mg *** CNTs refined the grains of the matrix,and the CNTs were presented throughout the extrusion *** the TiO2@CNTs content was 1.0 wt.%,the yield strength(yS),ultimate ten-sile strength(UTS),and elongation of the alloy attained maximum *** values were improved by 23.5%,82.1%,and 40.0%,respectively,when compared with the AZ91 *** interfacial bonding was achieved,which resulted in an effective tensile loading transfer at the *** carried the tensile stress and were observed on the tensile fracture.

关键词： Carbon nanotubes Titanium oxide AZ91 Coating Rare earth

Determination of Gravitomagnetic Field Through GRBs or X-ray Pulsars

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Communications in Theoretical Physics 2006年第5期45卷 858-860页

作者： wu ning ZHAng Da-Hua Institute of High Energy Physics P.O. Box 918-1 the Chinese AcademY of Sciences Beijing 100039 China

In gauge theory of gravity, there is direct coupling between the spin of a particle and gravitomagnetic field, which will affect Landau level. In the surface of a neutron star or near a black hole, the coupling energy between spin and gravitomagnetic field can be large and detectable. Precise measurement of the position of spectrum lines of the corresponding emission or absorption can help us to determine the gravitomagnetic field and electromagnetic field simultaneously. The ratio △ Ee/△Ep can be served as a quantitative criteria of black hole. In GRBs or X-ray pulsar, absorption spectral lines of electron were observed. If the absorption spectral lines of electron, neutron and proton can be observed simultaneously, using the method given in this paper, we can determine the gravitomagnetic field in the surface of the star, and discriminate black hole from neutron star.

关键词： gamma ray burst black holes gravitomagnetic field quantum effects of gravity

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一种低功耗可级联拓展的电刺激IC

半导体技术 2025年第1期50卷 64-70页

作者：吴黎霞张轩薛宁姚镭刘春秀中国科学院空天信息创新研究院传感器技术国家重点实验室北京100094 中国科学院大学电子电气与通信工程学院北京100094 上海矩智科技有限公司上海201899 临港实验室上海200031

设计了一种低功耗可级联拓展的电刺激芯片,该芯片主要由16个独立电刺激通道、一个全局数字控制器(GDC)及电流偏置模块组成。每个独立电刺激通道包含一个8 bit数模转换器(DAC)、一个高压刺激前端(SFE)电路以及通道本地数字控制器(LDC),... 详细信息

设计了一种低功耗可级联拓展的电刺激芯片,该芯片主要由16个独立电刺激通道、一个全局数字控制器(GDC)及电流偏置模块组成。每个独立电刺激通道包含一个8 bit数模转换器(DAC)、一个高压刺激前端(SFE)电路以及通道本地数字控制器(LDC),能够输出脉冲幅度/宽度/相位间隔时间可独立配置的单极性双相脉冲刺激电流。GDC控制16个通道的配置和刺激使能,并有一个可进行多芯片级联拓展的控制接口。LDC和GDC共用同一组时钟/数据控制信号,节省了端口资源。提出的电路采用GF 0.18μm CMOS BCD高压工艺进行设计和制备,总面积为1.5 mm×3.1 mm。测试结果表明,在5 V/15 V/-15 V供电下,该电路的静态功耗为2.14μW,最大输出电流为1 mA,输出200μA恒定电流时顺从电压为13.5 V。

关键词：电刺激集成电路(IC) 低功耗可拓展性多通道电刺激器

Seismic Imaging of Complex Structures in the Tarim Basin

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Journal of Earth Science 2015年第4期26卷 586-591页

作者： ning Guo Chao wu Stuart Fagin Geo Tech Groups LLC Institute of Exploration and Development CPNCKorla Geo Image Resources LLC

Conventional time imaging techniques are not capable of producing accurate seismic imaging of the subsurface in the mountain front of the Tarim Basin, China. Their imaged structures have led to some major drilling failures before, bearing a disrepute that ＂their structural closures have wheels and their structural highs have springs＂. This article first lists the imaging challenges, and explains in a schematic why the time imaging techniques fail in this area. Then through a series of real data examples, it demonstrates that when there exist lateral velocity variations, depth imaging is the only solution to tackle the imaging challenges in this area. Depth imaging accounts for the complexity of the wavefield, therefore produces superior and geological plausible images. The core task in properly performing depth imaging is building the velocity model. This article stresses some the main aspects in this regard.

关键词： time migration depth migration seismic image quality velocity model building anisotropy.

DTMC-based Modeling and Analysis of Obstacle Ad hoc Networks

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China Communications 2010年第5期7卷 83-92页

作者： Tong ning wu Di Wang Xiukun Department of Computer Science and Engineering Dalian University of Technology Dalian 116024 P. R. China Sheny.ng Aircraft Design ＆ Research Institute China Aviation Industry Corporation I Shenyang 110035 P. R. China

One of the main characteristics of Ad hoc networks is node mobility, which results in constantly changing in network topologies. Consequently, the ability to forecast the future status of mobility nodes plays a key role in QOS routing. We propose a random mobility model based on discretetime Markov chain, called ODM. ODM provides a mathematical framework for calculating some parameters to show the future status of mobility nodes, for instance, the state transition probability matrix of nodes, the probability that an edge is valid, the average number of valid-edges and the probability of a request packet found a valid route. Furthermore, ODM can account for obstacle environment. The state transition probability matrix of nodes can quantify the impact of obstacles. Several theorems are given and proved by using the ODM. Simulation results show that the calculated value can forecast the future status of mobility nodes.

关键词： Ad hoc network discrete time markov chain mobility model obstacle

An FTIR Study of Kyanite in the Maobei Kyanite-Bearing Eclogites from the Sulu Orogenic Belt, Eastern China

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Journal of Earth Science 2018年第1期29卷 21-29页

作者： yi-ning wu y.ng-Feng Wang School of Earth Sciences China University of Geosciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Global Tectonic Center School of Earth Sciences China University of Geosciences

As a minor phase, kyanite has been repeatedly shown to have experienced ultrahigh pressure （UHP） metamorphism together with its host eclogites. Thus, it could play some role in trans- porting water into the deep earth. Here we present a detailed investigation of water concentrations of kyanite, and for reference, of garnet and omphacite from four Maobei eclogites in the Sulu orogenic belt, eastern China. Fourier transform infrared （FTIR） measurements show that kyanites, garnets, and omphacites all have distinct hydroxyl absorption bands due to OH groups bound in their crystal struc- ture. The FTIR profile analyses on ten grains from different samples reveal a homogeneous distribution of water across kyanite, suggesting insignificant water loss during exhumation. The calculated water concentrations in kyanite （21 wt ppm-41 wt ppm） are comparable to those reported previously for kyanite from various geological occurrences when using the most recent calibration. They are however much lower compared with those in garnet （46 wt ppm-83 wt ppm） and omphacite （302 wt ppm-548 wt ppm） from the Maobei eclogites. This implies that kyanite is not a major water carrier in eclogites con- sidering its low volume fraction and contributes negligibly to transport water into the deep mantle ac- company.ng subducted oceanic crust until its possible transformation to AISiO3OH.

关键词： kyanite water contents eclogite Sulu orogenic belt.

Plasma membrane lipid scrambling causing phosphatidylserine exposure negatively regulates NK cell activation

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Cellular & Molecular Immunology 2021年第3期18卷 686-697页

作者： ning wu Hua Song Andre Veillette Laboratory of Molecular Oncology Institut de recherches cliniques de Montreal(IRCM)MontrealQC H2W1R7Canada Department of Immunology School of Basic MedicineTongji Medical CollegeHuazhong University of Science and Technology(HUST)WuhanChina Department of Medicine University of MontrealMontrealQC H3C3J7Canada Department of Medicine McGill UniversityMontrealQC H3G 1Y6f Canada

One of the hallmarks of live cells is the asymmetric distribution of lipids across their plasma *** in this asymmetry due to lipid"scrambling"result in phosphatidylserine exposure at the cell surface that is detected by annexin V *** alteration is observed during cell death processes such as apoptosis,and during physiological responses such as platelet degranulation and membrane *** studies have shown that activation of NK cells is accompanied by exposure of phosphatidylserine at the cell *** this response was thought to be indicative of ongoing NK cell death,it may also reflect the regulation of NK cell activation in the absence of cell ***,we found that NK cell activation was accompanied by rapid phosphatidylserine exposure to an extent proportional to the degree of NK cell *** enforced expression of a lipid scramblase,we provided evidence that activation-induced lipid scrambling in NK cells is reversible and does not lead to cell *** contrast,lipid scrambling attenuates NKcell *** response was accompanied by reduced cell surface expression of activating receptors such as 2B4,and by loss of binding of Src family protein tyrosine kinases Fyn and Lck to the inner leaflet of the plasma ***,lipid scrambling during NK cell activation is,at least in part,a physiological response that reduces the NK cell activation *** effect is due to the ability of lipid scrambling to alter the distribution of membrane-associated receptors and kinases required for NK cell activation.

关键词： NK cell activation Phosphatidylserine exposure Lipid scrambling TMEM16F Signaling