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“动+个+形”的认知探析——构式语法与认知语法的互动 被引量:2
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作者 张媛 《西安外国语大学学报》 2012年第3期29-32,共4页
从不可预测性和使用频率两个方面来看,"动+个+形"具有构式地位,作为语言单位具有整体压制作用,但也离不开组成部分在概念层次上的组合。"个"在该构式中仍是量词,形容词被"个"的原型意义名词化,整个构式... 从不可预测性和使用频率两个方面来看,"动+个+形"具有构式地位,作为语言单位具有整体压制作用,但也离不开组成部分在概念层次上的组合。"个"在该构式中仍是量词,形容词被"个"的原型意义名词化,整个构式表达动作实施所达到的非正常或极端状态,同时附加了说话者的主观期待值。此外,在语义形成过程中,转喻链机制发挥了促动作用。总之,对这一构式进行分析,需要取构式语法和认知语法各自的方法优势。 展开更多
关键词 “动+个+形” 构式 构式语法 认知语法
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现代汉语形容词的分布与认知研究——形容词作宾语的现象分析 被引量:3
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作者 王卫振 《忻州师范学院学报》 2011年第4期59-61,共3页
形容词是现代汉语语法研究中非常重要的一个词类,也是我们需要重点研究的内容之一,但是这些年来,我们对它的研究却不是那么深入,很多问题还有待于继续挖掘与思索。文章在这样大的时代研究背景下,试图通过对现代汉语"动+形"结... 形容词是现代汉语语法研究中非常重要的一个词类,也是我们需要重点研究的内容之一,但是这些年来,我们对它的研究却不是那么深入,很多问题还有待于继续挖掘与思索。文章在这样大的时代研究背景下,试图通过对现代汉语"动+形"结构的分析,力求找出动词与形容词的一般分布规律并利用认知语言学的理论来阐释与描写形容词作宾语的一般规律。希望通对这一问题的研究与阐述能激起更多的同行去深究与探索。形容词作宾语不是汉语语法复杂无规律的表现,这一点也正说明了汉语表达方式的灵活与丰富。 展开更多
关键词 “动+形” 宾语 分布 认知
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Sn nucleation and growth from Sn(II)dissolved in ethylene glycol:Electrochemical behavior and temperature effect
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作者 Kiem Van DO Hieu Van NGUYEN Tu Manh LE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2714-2732,共19页
Thermodynamic and kinetic aspects of Sn nucleation and growth processes onto a glassy carbon electrode from SnCl2·2H2O dissolved in ethylene glycol solutions were studied.Typical reduction and oxidation peaks obs... Thermodynamic and kinetic aspects of Sn nucleation and growth processes onto a glassy carbon electrode from SnCl2·2H2O dissolved in ethylene glycol solutions were studied.Typical reduction and oxidation peaks observed in voltammograms have demonstrated the capability of ethylene glycol solutions to electrodeposit Sn.The temperature-dependence of diffusion coefficient values derived from potentiodynamic and potentiostatic studies helped to determine and validate estimations of the activation energy for Sn(II)bulk diffusion.Chronoamperometric results have identified that,the suitable model to describe the early stage of Sn electrodeposition could be composed of Sn three-dimensional nucleation and diffusion-controlled growth and water reduction contributions,which was duly validated by theoretical and experimental approaches.From the model,typical kinetic parameters such as the nucleation frequency of Sn(A),number density of Sn nuclei(N_(0)),and diffusion coefficient of Sn(II)ions(D),were determined.The presence of Sn nuclei with excellent quality and their structures were verified using SEM,EDX,and XRD techniques. 展开更多
关键词 SN NUCLEATION growth ethylene glycol nucleation kinetics ELECTRODEPOSITION
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Support design method for deep soft-rock tunnels in non-hydrostatic high in-situ stress field
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作者 ZHENG Ke-yue SHI Cheng-hua +3 位作者 ZHAO Qian-jin LEI Ming-feng JIA Chao-jun PENG Zhu 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2431-2445,共15页
Due to the long-term plate tectonic movements in southwestern China,the in-situ stress field in deep formations is complex.When passing through deep soft-rock mass under non-hydrostatic high in-situ stress field,tunne... Due to the long-term plate tectonic movements in southwestern China,the in-situ stress field in deep formations is complex.When passing through deep soft-rock mass under non-hydrostatic high in-situ stress field,tunnels will suffer serious asymmetric deformation.There is no available support design method for tunnels under such a situation in existing studies to clarify the support time and support stiffness.This study first analyzed the mechanical behavior of tunnels in non-hydrostatic in-situ stress field and derived the theoretical equations of the ground squeezing curve(GSC)and ground loosening curve(GLC).Then,based on the convergence confinement theory,the support design method of deep soft-rock tunnels under non-hydrostatic high in-situ stress field was established considering both squeezing and loosening pressures.In addition,this method can provide the clear support time and support stiffness of the second layer of initial support.The proposed design method was applied to the Wanhe tunnel of the China-Laos railway in China.Monitoring data indicated that the optimal support scheme had a good effect on controlling the tunnel deformation in non-hydrostatic high in-situ stress field.Field applications showed that the secondary lining could be constructed properly. 展开更多
关键词 non-hydrostatic stress field high in-situ stress deep soft-rock tunnel squeezing pressure loosening pressure support design method
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Flow softening behavior and microstructure evolution of Al-5Zn-2Mg aluminum alloy during dynamic recovery 被引量:13
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作者 李落星 王冠 +1 位作者 刘杰 姚再起 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第1期42-48,共7页
The flow stress behavior and microstructure development of Al-5Zn-2Mg (7005) aluminum alloy were studied by hot compression tests at deformation temperatures between 300-500 &#176;C and strain rates between 0.05-50... The flow stress behavior and microstructure development of Al-5Zn-2Mg (7005) aluminum alloy were studied by hot compression tests at deformation temperatures between 300-500 &#176;C and strain rates between 0.05-50 s-1. The deformed structures of the samples were observed by optical microscopy (OM), transmission electron microscopy (TEM) and electron backscattering diffraction (EBSD) analysis. The calculated activation energy is 147 kJ/mol, which is very close to the activation energy for lattice self-diffusion in aluminum (142 kJ/mol). Dynamic recovery is the dominant restoration mechanism during the deformation. At high strain rate of 50 s-1, temperature rise due to deformation heating leads to a significant flow softening. Microstructure observations indicated that the remaining softening after deformation heating correction at high strain rate and the softening observed at high temperature are associated with grain coarsening induced by grain boundary migration during dynamic recovery process. 展开更多
关键词 7005 aluminum alloy DEFORMATION dynamic recovery flow softening microstructure evolution
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LOCALIZATION OF OBJECT (SPINE) IN MEDICAL IMAGE USING ACTIVE SHAPE MODELS 被引量:2
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作者 徐涛 蔡宇新 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第2期211-217,共7页
Active shape models (ASM), consisting of a shape model and a local gray-level appearance model, can be used to locate the objects in images. In original ASM scheme, the model of object′s gray-level variations is base... Active shape models (ASM), consisting of a shape model and a local gray-level appearance model, can be used to locate the objects in images. In original ASM scheme, the model of object′s gray-level variations is based on the assumption of one-dimensional sampling and searching method. In this work a new way to model the gray-level appearance of the objects is explored, using a two-dimensional sampling and searching technique in a rectangular area around each landmark of object shape. The ASM based on this improvement is compared with the original ASM on an identical medical image set for task of spine localization. Experiments demonstrate that the method produces significantly fast, effective, accurate results for spine localization in medical images. 展开更多
关键词 object localization active shape models (ASM) gray-level appearance model principal component analysis SPINE
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浅谈中国养生体育的基本特征 被引量:7
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作者 王志祥 《医学与哲学》 2002年第3期51-52,共2页
关键词 中国 养生体育 “清静养神” “动以养形” 神俱养”
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Numerical simulation of dynamic surface deformation based on DInSAR monitoring 被引量:2
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作者 阎跃观 戴华阳 +3 位作者 葛林林 郭俊廷 AlexHay-ManNG 李晓静 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1248-1254,共7页
Differential interferometric synthetic aperture radar (DInSAR) technology is a new method to monitor the dynamic surface subsidence. It can monitor the large scope of dynamic deformation process of surface subsidenc... Differential interferometric synthetic aperture radar (DInSAR) technology is a new method to monitor the dynamic surface subsidence. It can monitor the large scope of dynamic deformation process of surface subsidence basin and better reflect the surface subsidence form in different stages. But under the influence of factors such as noise and other factors, the tilt and horizontal deformation curves regularity calculated by DInSAR data are poorer and the actual deviation is larger. The tilt and horizontal deformations are the important indices for the safety of surface objects protection. Numerical simulation method was used to study the dynamic deformation of LW32 of West Cliff colliery in Australia based on the DInSAR monitoring data. The result indicates that the subsidence curves of two methods fit well and the correlation coefficient is more than 95%. The other deformations calculated by numerical simulation results are close to the theory form. Therefore, considering the influence, the surface and its subsidiary structures and buildings due to mining, the numerical simulation method based on the DInSAR data can reveal the distribution rules of the surface dynamic deformation values and supply the shortcomings of DInSAR technology. The research shows that the method has good applicability and can provide reference for similar situation. 展开更多
关键词 DInSAR monitoring numerical simulation dynamic surface deformation SUPPLEMENT
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Review on the proceeding of automatic seedlings classification by computer vision 被引量:1
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作者 杨延竹 赵学增 +1 位作者 王伟杰 吴羡 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第3期245-249,252,共5页
The classification of seedlings is important to ensure the viability of seedlings after transplantation and is acknowledged as a key factor in forestation and environmental improvement. Based on numerous papers on aut... The classification of seedlings is important to ensure the viability of seedlings after transplantation and is acknowledged as a key factor in forestation and environmental improvement. Based on numerous papers on automatic seedling classification (ASC), the seedling grading theory, traditional grading methods, the background and the proceeding of ASC techniques are described. The automation of the measurement of seedling morphological characteristics by photoelectric meters and computer vision is studied, and the automatic methods of the current grading systems are described respectively. And the further researches on ASC by computer vision are proposed. 展开更多
关键词 Seedlings classification AUTOMATION Morphological characteristic Computer vision
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Rate controlling mechanisms in hot deformation of 7A55 aluminum alloy 被引量:4
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作者 冯迪 张新明 +2 位作者 刘胜胆 吴泽政 谈琦 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第1期28-35,共8页
The hot deformation behavior of 7A55 aluminum alloy was investigated at the temperature ranging from 300 ℃ to 450 ℃ and strain rate ranging from 0.01 s-1 to 1 s-1 on a Gleeble-3500 simulator. Processing maps were es... The hot deformation behavior of 7A55 aluminum alloy was investigated at the temperature ranging from 300 ℃ to 450 ℃ and strain rate ranging from 0.01 s-1 to 1 s-1 on a Gleeble-3500 simulator. Processing maps were established in order to apprehend the kinetics of hot deformation and the rate controlling mechanism was interpreted by the kinetic rate analysis obeying power-law relation. The results indicated that one significant domain representing dynamic recrystallization (DRX) existed on the processing maps and lying in 410-450 &#176;C and 0.05-1 s-1. The conclusions of kinetic analysis correlated well with those obtained from processing maps. The apparent activation energy values calculated in the dynamic recrystallization (DRX) domain and the stability regions except dynamic recrystallization (DRX) domain were 91.2 kJ/mol and 128.8 kJ/mol, respectively, which suggested that grain boundary self-diffusion and cross-slip were the rate controlling mechanisms. 展开更多
关键词 7A55 aluminum alloy processing maps hot deformation kinetic analysis dynamic recrystallization
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Hot deformation behavior and processing map of Cu-Ni-Si-P alloy 被引量:6
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作者 张毅 刘平 +3 位作者 田保红 刘勇 李瑞卿 许倩倩 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第8期2341-2347,共7页
The high-temperature deformation behavior of Cu-Ni-Si-P alloy was investigated by using the hot compression test in the temperature range of 600-800 ℃ and strain rate of 0.01-5 s-1. The hot deformation activation ene... The high-temperature deformation behavior of Cu-Ni-Si-P alloy was investigated by using the hot compression test in the temperature range of 600-800 ℃ and strain rate of 0.01-5 s-1. The hot deformation activation energy, Q, was calculated and the hot compression constitutive equation was established. The processing maps of the alloy were constructed based on the experiment data and the forging process parameters were then optimized based on the generated maps for forging process determination. The flow behavior and the microstructural mechanism of the alloy were studied. The flow stress of the Cu-Ni-Si-P alloy increases with increasing strain rate and decreasing deformation temperature, and the dynamic recrystallization temperature of alloy is around 700 ℃. The hot deformation activation energy for dynamic recrystallization is determined as 485.6 kJ/mol. The processing maps for the alloy obtained at strains of 0.3 and 0.5 were used to predict the instability regimes occurring at the strain rate more than 1 s-1 and low temperature (〈650 ℃). The optimum range for the alloy hot deformation processing in the safe domain obtained from the processing map is 750-800 ℃ at the strain rate of 0.01-0.1 s i The characteristic microstructures predicted from the processing map agree well with the results of microstructural observations. 展开更多
关键词 Cu-Ni-Si-P alloy hot compression deformation dynamic recrystallization constitutive equation processing maps
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Hot deformation behavior of high Ti 6061 Al alloy 被引量:3
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作者 陈微 官英平 王振华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第2期369-377,共9页
The hot deformation behavior of a high Ti 6061 aluminum alloy in the temperature range from 350 to 510 ℃ and strain rate range from 0.001 to 10 s^-1 was investigated using stress-strain curve analysis, processing map... The hot deformation behavior of a high Ti 6061 aluminum alloy in the temperature range from 350 to 510 ℃ and strain rate range from 0.001 to 10 s^-1 was investigated using stress-strain curve analysis, processing map, transmission electron microscopy and electron backscatter diffraction analysis. The results show that the peak stress decreases with increasing deformation temperatures and decreasing strain rate. The average deformation activation energy is 185 kJ/mol in the parameter range investigated. The flow stress model was constructed. The main softening mechanism is dynamic recovery. The processing map was obtained using dynamic material model, and the suggested processing window is 400-440℃ and 0.001-0.1 s^-1. 展开更多
关键词 6061 A1 alloy hot deformation dynamic recovery hot processing map DISLOCATION
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Hot deformation behavior and microstructural evolution of beta C titanium alloy in β phase field 被引量:12
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作者 许鑫 董利民 +2 位作者 巴宏波 张志强 杨锐 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第11期2874-2882,共9页
The hot deformation behavior of beta C titanium alloy in β phase field was investigated by isothermal compression testson a Gleeble?3800 thermomechanical simulator. The constitutive equation describing the hot defor... The hot deformation behavior of beta C titanium alloy in β phase field was investigated by isothermal compression testson a Gleeble?3800 thermomechanical simulator. The constitutive equation describing the hot deformation behavior was obtained anda processing map was established at the true strain of 0.7. The microstructure was characterized by optical microscopy (OM),scanning electron microscopy (SEM) and electron back-scattered diffraction (EBSD) technique. The results show that the flow stressincreases with increasing strain rates, and decreases with increasing experimental temperatures. The calculated apparent activationenergy (167 kJ/mol) is close to that of self-diffusion in β titanium. The processing map and microstructure observation exhibit adynamic recrystallization domain in the temperature range of 900-1000 ℃ and strain rate range of 0.1-1 s^-1. An instability regionexists when the strain rate is higher than 1.7 s^-1. The microstructure of beta C titanium alloy can be optimized by proper heattreatments after the deformation in the dynamic recrystallization domain. 展开更多
关键词 titanium alloy hot deformation dynamic recrystallization processing map
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Dynamic recovery and dynamic recrystallization of NiTi shape memory alloy under hot compression deformation 被引量:12
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作者 江树勇 张艳秋 赵亚楠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第1期140-147,共8页
Mechanical behavior of nickel?titanium shape memory alloy(NiTi SMA) under hot deformation was investigated according to the true stress—strain curves of NiTi samples under compression at the strain rates of 0.001-... Mechanical behavior of nickel?titanium shape memory alloy(NiTi SMA) under hot deformation was investigated according to the true stress—strain curves of NiTi samples under compression at the strain rates of 0.001-1 s-1 and at the temperatures of 600?1000℃.Dynamic recovery and dynamic recrystallization of NiTi SMA were systematically investigated by microstructural evolution.The influence of the strain rates,the deformation temperatures and the deformation degree on the dynamic recovery and dynamic recrystallization of NiTi SMA was obtained as well.NiTi SMA was characterized by the combination of dynamic recovery and dynamic recrystallization at 600℃ and 700℃,but the complete dynamic recrystallization occurred at other deformation temperatures.Increasing the deformation temperatures or decreasing the stain rates leads to larger equiaxed grains.The deformation degree has an important influence on the dynamic recrystallization of NiTi SMA.There exists the critical deformation degree during the dynamic recrystallization of NiTi SMA,beyond which the larger deformation degree contributes to obtaining the finer equiaxed grains. 展开更多
关键词 NiTi alloy shape memory alloy dynamic recovery dynamic recrystallization hot deformation
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Dynamic caustics experimental study on interaction between propagating crack and deformity inclusions in primary structure 被引量:2
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作者 岳中文 韩瑞杰 +1 位作者 张旺 刘伟 《Journal of Southeast University(English Edition)》 EI CAS 2016年第1期73-77,共5页
The approach combining the dynamic caustics method with high-speed photography technology is used to study the interaction between propagating cracks and three kinds of deformity inclusions( cylinder inclusion, quadr... The approach combining the dynamic caustics method with high-speed photography technology is used to study the interaction between propagating cracks and three kinds of deformity inclusions( cylinder inclusion, quadruple inclusion and triangular inclusion) under lowvelocity impact loading. By recording the caustic spots of crack tips at different moments during the crack propagation, the variation regulations of dynamic stress intensity factors( DSIF) and crack growth velocity with respect to time are obtained. The experimental results showthat the resistance effects to crack growth are varied with different shapes of inclusions in specimens, and the quadruple inclusion's effect is more apparent. The distortion degree of caustic spots is affected by the shapes of inclusions as well, and the situation is more serious for cylinder and quadruple inclusions. The overall values of DSIFs of triangular inclusion specimen are greater than the others, and the crack growth velocities, characteristic sizes and DSIFs showprocesses of fluctuations because of the disturbance of reflection waves in specimens. The results provide an experimental basis for the analysis of strength and impact-resistance ability in structures with deformity inclusions. 展开更多
关键词 dynamic caustics deformity inclusion dynamic stress intensity factor(DSIF) crack propagation velocity
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New seismic attribute:Fractal scaling exponent based on gray detrended fluctuation analysis 被引量:1
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作者 黄亚平 耿建华 郭彤楼 《Applied Geophysics》 SCIE CSCD 2015年第3期343-352,467,共11页
Seismic attributes have been widely used in oil and gas exploration and development. However, owing to the complexity of seismic wave propagation in subsurface media, the limitations of the seismic data acquisition sy... Seismic attributes have been widely used in oil and gas exploration and development. However, owing to the complexity of seismic wave propagation in subsurface media, the limitations of the seismic data acquisition system, and noise interference, seismic attributes for seismic data interpretation have uncertainties. Especially, the antinoise ability of seismic attributes directly affects the reliability of seismic interpretations. Gray system theory is used in time series to minimize data randomness and increase data regularity. Detrended fluctuation analysis (DFA) can effectively reduce extrinsic data tendencies. In this study, by combining gray system theory and DFA, we propose a new method called gray detrended fluctuation analysis (GDFA) for calculating the fractal scaling exponent. We consider nonlinear time series generated by the Weierstrass function and add random noise to actual seismic data. Moreover, we discuss the antinoise ability of the fractal scaling exponent based on GDFA. The results suggest that the fractal scaling exponent calculated using the proposed method has good antinoise ability. We apply the proposed method to 3D poststack migration seismic data from southern China and compare fractal scaling exponents calculated using DFA and GDFA. The results suggest that the use of the GDFA-calculated fractal scaling exponent as a seismic attribute can match the known distribution of sedimentary facies. 展开更多
关键词 Seismic attribute gray system theory detrended fluctuation analysis fractal scaling exponent
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Structure design and simulation of MEMS vibrating ring gyroscope 被引量:2
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作者 寇志伟 曹慧亮 +2 位作者 石云波 刘俊 唐军 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第1期78-83,共6页
MEMS gyroscope is a new inertial navigation sensor,which can measure the input angular rate of sensitive axis using Coriolis effect.Compared to the conventional gyroscope,it owns many unique advantages.A novel structu... MEMS gyroscope is a new inertial navigation sensor,which can measure the input angular rate of sensitive axis using Coriolis effect.Compared to the conventional gyroscope,it owns many unique advantages.A novel structure of vibrating ring gyroscope is proposed and the finite element model of the oscillator is established based on MEMS technology.Through the modal analysis,the natural frequency and mode shapes of the oscillator are obtained.By analyzing the effects of the structural parameters on the mode shapes and frequency of the harmonic oscillator,the optimal design parameters are got.The frequency difference between the operating mode and the other modes is greater than 1kHz after optimization,which can avoid the frequency coupling of the operating mode and other vibrating modes of the oscillator.The simulation results show that the performance parameters of the ring structure meet the design requirements and have obvious advantages. 展开更多
关键词 MEMS vibrating ring gyroscope inertial sensor angular rate solid wave gyroscope
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Enhancement of nucleation of diamond films deposited on copper substrate by nickel modification layer 被引量:3
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作者 刘学璋 魏秋平 +1 位作者 翟豪 余志明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第3期667-673,共7页
A Ni layer with a thickness of about 100 nm was sputtered on Cu substrates,followed by an ultrasonic seeding with nanodiamond suspension.High-quality diamond film with its crystalline grains close to thermal equilibri... A Ni layer with a thickness of about 100 nm was sputtered on Cu substrates,followed by an ultrasonic seeding with nanodiamond suspension.High-quality diamond film with its crystalline grains close to thermal equilibrium shape was deposited on Cu substrates by hot-filament chemical vapor deposition(HF-CVD),and the sp2 carbon content was less than 5.56%.The nucleation and growth of diamond film were investigated by micro-Raman spectroscopy,scanning electron microscopy,and X-ray diffraction.The results show that the nucleation density of diamond on the Ni-modified Cu substrates is 10 times higher than that on blank Cu substrates.The enhancement mechanism of the nucleation kinetics by Ni modification layer results from two effects:namely,the nanometer rough Ni-modified surface shows an improved absorption of nanodiamond particles that act as starting points for the diamond nucleation during HF-CVD process;the strong catalytic effect of the Ni-modified surface causes the formation of graphite layer that acts as an intermediate to facilitate diamond nucleation quickly. 展开更多
关键词 diamond film nickel interlayer Cu substrate chemical vapor deposition nucleation kinetics surface modification
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MODELING OF SCG ROTOR DRIFT AND MEASURING SCHEME 被引量:1
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作者 汤继强 房建成 张延顺 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第1期17-24,共8页
Based on micro-displacement measurement principles of the spherical differential capacitance sensor, the relationship between the capacitance variation and the micro-displacement of each pair of detecting electrodes f... Based on micro-displacement measurement principles of the spherical differential capacitance sensor, the relationship between the capacitance variation and the micro-displacement of each pair of detecting electrodes for the superconducting gyroscope (SCG) with eight detecting electrodes is analyzed. The model of the SCG rotor drift is established through dimensionless processing, linearization within micro-displacement and the least-square approach. Both the measurement scheme of the SCG rotor drift based on the model and its parameter relationship are presented. To guarantee the potential of the suspension rotor to be zero, the distributing scheme of four pairs of detecting electrodes is presented. The scheme can measure the magnitude and the direction of the rotor drift. The negative factors for affecting the measurement precision of .the SCG rotor drift and simulation results of the total effects are given. Simulation results show that the distributing capacitance of these differential capacitance sensors, the zero potential of the rotor and the model error are the major negative factors. The methods for eliminating those negative factors and the application range of the model are given. The model ensures the relationship between the output voltage and the rotor drift be linear. 展开更多
关键词 superconducting gyroscope suspension rotor DRIFT spherical differential capacitance MICRO-DISPLACEMENT
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Microstructures and mechanical properties of Mg-Al-Sm series heat-resistant magnesium alloys 被引量:7
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作者 黄正华 戚文军 +1 位作者 徐静 蔡畅 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第1期22-29,共8页
The microstructures and phase compositions of the as-cast and die-cast Mg-6.02Al-1.03 Sm, Mg-6.05Al-0.98Sm-0.56 Bi and Mg-5.95Al-1.01Sm-0.57 Zn alloys were investigated. Meanwhile, the tensile mechanical and flow prop... The microstructures and phase compositions of the as-cast and die-cast Mg-6.02Al-1.03 Sm, Mg-6.05Al-0.98Sm-0.56 Bi and Mg-5.95Al-1.01Sm-0.57 Zn alloys were investigated. Meanwhile, the tensile mechanical and flow properties were tested. The results show that the as-cast microstructure of Mg-6.02Al-1.03 Sm alloy is composed of δ-Mg matrix, discontinuous δ-Mg17Al12 phase and small block Al2 Sm phase with high thermal stability. Rod Mg3Bi2 phase precipitates when Bi is added, while the added metal Zn dissolves into δ-Mg matrix and δ-Mg17Al12 phase. The as-cast alloys exhibit the excellent tensile mechanical property. The tensile strength(δb) and elongation(δ) can reach 205-235 MPa and 8.5%-16.0% at ambient temperature, respectively. Meanwhile, they can also exceed 160 MPa and 14.0% at 423 K, respectively. The die-cast microstructures are refined obviously, and meanwhile the broken second phases distribute dispersedly. The die-cast alloys exhibit better tensile mechanical properties with the values of δb and δ of 240-285 MPa and 8.5%-16.5% at ambient temperature, respectively, and excellent flow property with the flow length of 1870-2420 mm. The die-cast tensile fractures at ambient temperature exhibit a typical character of ductile fracture. 展开更多
关键词 heat-resistant magnesium alloy Mg-Al-Sm alloy MICROSTRUCTURE mechanical property flow property fracture morphology
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