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Six million Q factor micro fused silica shell resonator with teeth-like tines released by femtosecond laser-assisted chemical etching

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Science China(Technological Sciences) 2024年第6期67卷 1923-1932页

作者： ZHAO Tao SHI Yan LU Kun XI Xiang wu xuezhong XIAO DingBang College of Intelligence Science and Engineering National University of Defense TechnologyChangsha410073China

The quality factor(Q factor)is a crucial performance parameter for *** this paper,a novel release method for highquality micro fused silica shell resonators with teeth-like tines with good surface morphology is *** method is based on femtosecond laser-assisted chemical ***,the optimal energy range of femtosecond laser modification is obtained through mechanism ***,the optimal parameters for a straight line and arc pattern are determined by optimizing the average output power,processing speed,and processing *** results demonstrate why edge breakage in rounded corners is easy under different ***,according to these conclusions,the processing is performed on a micro fused silica shell resonator with a Q factor exceeding 6 *** addition,subsurface damage is rare throughout the fabrication process,and the surface roughness of the released cross section reaches the nanometer *** improved Q factor helps suppress mechanical thermal noise and reduce zero bias and zero bias drift,constituting the primary method for enhancing the performance of the resonant gyroscope.

关键词： micro hemispherical resonator fused silica laser-assisted chemical etching quality factor

Modeling and Analysis of Mechanical Quality Factor of the Resonator for Cylinder Vibratory Gyroscope

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Chinese Journal of Mechanical Engineering 2017年第1期30卷 180-189页

作者： XI Xiang wu xuezhong wu Yulie ZHANG Yongmeng College of Mechatronics Engineering and Automation National University of Defense TechnologyChangsha 410073China

Mechanical Quality factor（Q factor） of the resonator is an important parameter for the cylinder vibratory gyroscope（CVG）. Traditional analytical methods mainly focus on a partial energy loss during the vibration process of the CVG resonator, thus are not accurate for the mechanical Q factor prediction. Therefore an integrated model including air damping loss, surface defect loss, support loss, thermoelastic damping loss and internal friction loss is proposed to obtain the mechanical Q factor of the CVG resonator. Based on structural dynamics and energy dissipation analysis, the contribution of each energy loss to the total mechanical Q factor is quantificationally analyzed. For the resonator with radius ranging from 10 mm to 20 mm, its mechanical Q factor is mainly related to the support loss, thermoelastic damping loss and internal friction loss, which are fundamentally determined by the geometric sizes and material properties of the resonator. In addition, resonators made of alloy 3J53 （Ni42CrTiA1）, with different sizes, were experimentally fabricated to test the mechanical Q factor. The theoretical model is well verified by the experimental data, thus provides an effective theoretical method to design and predict the mechanical Q factor of the CVG resonator.

关键词： mechanical Quality factor cylinder vibratory gyroscope energy loss

Design and Characterization of a Novel Z-axis Quartz Cross-fork Micromachined Gyroscope

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Chinese Journal of Mechanical Engineering 2011年第1期24卷 50-57页

作者： XIE Liqiang wu xuezhong LI Shengyi WANG Haoxu TAO Yi DONG Peitao College of Mechatronics Engineering andAutomation National University of Defense Technology Changsha 410073 China Engineering Institute of Engineering Corps PLA University of Science and Technology Nanjing 210007 China wuhan Ordnance N. C. O. Academy Wuhan 430075 China

The existing researches on quartz gyroscope mainly focus on the structure design of the tuning fork, which aim at obtaining a better vibration characterization. However, the fabrication of complicated structure is a challenge for present processes, and the imperfect fabrication process seriously affects the performances of the sensors. In this paper, a novel quartz cross-fork structure micromachined gyroscope is proposed. The sensor has a simple structure in x-y plane of quartz crystal. Unlike other quartz gyroscopes, the proposed gyroscope is based on shear stress detection to sense Coriolis’ force rather than normal stress detection. This feature can simplify the sensing electrode patterns and miniaturize the structure easily. Then the mechanical analysis of the structure is discussed. In order to obtain high sensitivities and uniform characteristics between different structures, the sensing beam is designed to be tapered, and the taper should be appreciably greater than 1°. This scheme is validated by finite element analysis software. The dynamic characteristic of the structure is analyzed by lumped parameter model. The dynamic stress in the beam and the detection sensitivity are deduced to optimize the structure parameter of gyroscope. Finally, the gyroscope is fabricated by quartz anisotropic wet etching. The prototype is characterized as follows. The drive mode frequency is 13.38 kHz, and the quality factor is about 900 in air. The scale factor is 1.45 mV/（（°） s –1 ） and the nonlinearity is 3.6% in the dynamic range of ±200°/s. Process and test results show that the proposed quartz gyroscope can achieve a high performance at atmosphere pressure. The research can simplify the fabrication of the quartz gyroscope, and is taken as a novel method for the design of quartz gyroscope.

关键词： quartz gyroscope cross-fork dynamic analysis Coriolis’ force

Precision Balance Method for Cupped Wave Gyro Based on Cup-bottom Trimming

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Chinese Journal of Mechanical Engineering 2012年第1期25卷 63-70页

作者： TAO Yi XI Xiang XIAO Dingbang TAN Yingqi CUI Hongjuan wu xuezhong College of Mecha tronics Engineering and Automation National University of Defense TechnologyChangsha 410073China wuhan Ordnance N.C.O.Academy Wuhan 430075China Department of Mechatronics Engineering Zhuhai CollegeJilin UniversityZhuhai 519041China

The mechanical balance process is the key process to eliminate the quadrature error and improve the performance of the cupped wave gyro. The conventional mechanical balance method for cupped wave gyro based on cup-wall trimming requires high control accuracy of trimming quantity, which increases the production cost and decreases the fabrication efficiency in large extent. However, it is hard to reach the high balance accuracy with the natural frequency split of mHz grade by using the conventional method. In this paper, the lumped mass dynamic model of the cupped wave gyro is built by discretization method, and the effects of different position trimming on the natural frequency are analyzed. It is pointed out that trimming off a tiny quantity of material from cup-wall causes large variation of the natural frequency is the main reason for the low accuracy of the conventional mechanical balance method. Then, a precision balance method for cupped wave gyro based on cup-bottom trimming is presented and the entire procedures of this method are given. The static balance process and dynamic balance process of the precision balance method are simulated by the finite element software. The simulation result shows that the precision balance method based on cup-bottom trimming brings less additional natural frequency split in the static balance process, minimizes the natural frequency split to mHz grade and rectify the angle of mode offset to 0.1° grade in the dynamic balance process, furthermore, the method decreases the requirement for control accuracy of trimming quantity evidently. The research work provides references for structure optimization design and balance process plan of the cupped wave gyro.

关键词： cupped wave gyro precision balance trimming modal analysis natural frequency split

Removal of the rate table:MEMS gyrocompass with virtual maytagging

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Microsystems & Nanoengineering 2023年第6期9卷 175-184页

作者： Tongqiao Miao Qingsong Li Liangqian Chen Junjian Li Xiaoping Hu xuezhong wu Wenqi wu Dingbang Xiao College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China

High-performance micro-electro-mechanical system(MEMS)gyrocompasses for north-finding systems have been very popular for *** this paper,a MEMS north-finding system(NFS)based on virtual maytagging(VM)is presented for the first *** stark contrast to previous schemes of MEMS-based NFSs(e.g.,carouseling,maytagging)and the abandoning rate table,we developed a honeycomb disk resonator gyroscope(HDRG)and two commercial accelerometers for azimuth *** of the physical rotation of the integrated turntable in traditional NFSs,the vibratory working modes of the HDRG are rotated periodically with electronic control to reduce the uncertainty in the *** systematically analyzing the principle of NFSs with VM,we designed tests to verify the practicability at the sensor level.A bias instability of 0.0078°/h can be obtained during one day with VM in an *** also implemented comparative north-finding experiments to further check our strategy at the system *** accuracy in the azimuth can reach 0.204°for 5 min at 28.2°latitude with VM and 0.172°with *** results show that without any mechanical turning parts,VM technology makes it possible to develop high-precision handheld MEMS NFSs.

关键词： NFS virtual system

Model of NBTI combined with mobility degradation

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Journal of Semiconductors 2018年第12期39卷 141-146页

作者： xuezhong wu Chenyue Ma Shucheng Gao Xiangbin Li Fu Sun Lining Zhang Xinnan Lin The Shenzhen Key Lab of Advanced Electron Device and Integration ECE PKUSZ College of Electronic Science and Technology Shenzhen University

The mobility degradation induced by negative bias temperature instability(NBTI) is usually ignored in traditional NBTI modeling and simulation, resulting in overestimation of the circuit lifetime, especially after longterm operation. In this paper, the mobility degradation is modeled in combination with the universal NBTI *** coulomb scattering induced by interface states is revealed to be the dominant component responsible for mobility degradation. The proposed mobility degradation model fits the measured data well and provides an accurate solution for evaluating coupling of NBTI with HCI(hot carrier injection) and SHE(self-heating effect), which indicates that mobility degradation should be considered in long-term circuit aging simulation.

关键词： NBTI mobility degradation aging simulation algorithm hot carrier injection self-heating effect coupling

Spatial dynamics of a reaction-diffusion SIS epidemic model with mass-action-type nonlinearity

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International Journal of Biomathematics 2024年第4期17卷 75-104页

作者： Renhu Wang xuezhong Wang School of Mathematics and Statistics Lanzhou University LanzhouGansu 730000P.R.China School of Mathematics and Statistics Heci University Zhangye 734000P.R.China

This work is devoted to investigate the global asymptotic stability of equilibriums for a reaction-diffusion susceptible-infected-susceptible(SIS)epidemic model with spatial heterogeneity and mass-action-type *** discretizing the spatial variables of the model,first,Lyapunov functions are constructed for the corresponding ordinary differential equations(ODEs)model of the original SIS PDEs model,and then the construction method is generalized to the PDEs model in which either the susceptible or the infectious individuals are spreading in spatial heterogeneity *** both the cases,we obtained the standard threshold dynamics results.

关键词： Discretization basic reproduction number Lyapunov functional global stability spatial heterogeneity

Identification of TNFRSF1A as a novel regulator of carfilzomib resistance in multiple myeloma

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Oncology Research 2024年第2期32卷 325-337页

作者： JIE ZHAO XUANTAO YANG HAIXI ZHANG xuezhong GU Department of Hematology The First People’s Hospital of Yunnan ProvinceYunnan Province Clinical Research Center for Hematologic DiseaseYunnan Province Clinical Center for Hematologic DiseaseKunming650032China Department of Pathology The First People’s Hospital of Yunnan ProvinceKunming650032China

Multiple myeloma(MM)is a hematological tumor with high mortality and recurrence *** is a new-generation proteasome inhibitor that is used as the first-line therapy for ***,the development of drug resistance is a pervasive obstacle to treating ***,elucidating the drug resistance mechanisms is conducive to the formulation of novel therapeutic *** elucidate the mechanisms of carfilzomib resistance,we retrieved the GSE78069 microarray dataset containing carfilzomib-resistant LP-1 MM cells and parental MM *** gene expression analyses revealed major alterations in the major histocompatibility complex(MHC)and cell adhesion *** upregulation of the tumor necrosis factor(TNF)receptor superfamily member 1A(TNFRSF1A)gene was accompanied by the downregulation of MHC genes and cell adhesion ***,to investigate the roles of these genes,we established a carfilzomib-resistant cell model and observed that carfilzomib resistance induced TNFRSF1A overexpression and TNFRSF1A silencing reversed carfilzomib resistance and reactivated the expression of cell adhesion ***,TNFRSF1A silencing suppressed the tumorigenesis of MM cells in immunocompetent mice,indicating that TNFRSF1A may lead to carfilzomib resistance by dampening antitumor ***,our results indicated that TNFRSF1A overexpression conferred carfilzomib resistance in MM cells and suppressed the expression of MHC genes and cell adhesion *** suppression of MHC genes and cell adhesion molecules may impair the interaction between immune cells and cancer cells to impair antitumor *** studies are warranted to further investigate the signaling pathway underlying the regulatory role of TNFRSF1A in MM cells.

关键词： Multiple myeloma Carfilzomib Drug resistance Major histocompatibility complex TNFRSF1A

0.79 ppm scale-factor nonlinearity whole-angle microshell gyroscope realized by real-time calibration of capacitive displacement detection

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Microsystems & Nanoengineering 2021年第5期7卷 129-139页

作者： Jiangkun Sun Sheng Yu Yongmeng Zhang Qingsong Li Xiang Xi Kun Lu xuezhong wu Dingbang Xiao National University of Defense Technology Changsha 410073China

Whole-angle gyroscopes have broad prospects for development with inherent advantages of excellent scale factor,wide bandwidth and measurement range,which are restrictions on rate *** studies on the whole-angle mode are based mostly on the linear model of Lynch,and the essential nonlinearity of capacitive displacement detection is always neglected,which has significant negative effects on the *** this paper,a novel realtime calibration method of capacitive displacement detection is proposed to eliminate these nonlinear *** novel method innovatively takes advantage of the relationship between the first and third harmonic components of detective signals for *** on this method,the real-time calibration of capacitive displacement detection is achieved and solves the problems of traditional methods,which are usually related to the vibration amplitude,environmental variations and other ***,this novel calibration method is embedded into a whole-angle control system to restore the linear capacitive response in real time and then combined with a microshell resonator for the first time to exploit the enormous potential of an ultrahigh Q factor and symmetric *** effectiveness is proven because the angle drift is reduced significantly to improve the scale-factor nonlinearity by 14 times to 0.79 ppm with 0.0673/h bias instability and a 0.0017s rate threshold,which is the best reported performance of the MEMS whole-angle gyroscope thus *** importantly,this novel calibration method can be applied for all kinds of resonators with the requirement of a linear capacitive response even under a large resonant amplitude.

关键词： structure nonlinearity displacement