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Design and Fabrication of MEMS Gyroscopes on the Silicon-on-insulator Substrate with Decoupled Oscillation Modes

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Chinese Journal of Mechanical Engineering 2010年第1期23卷 16-20页

作者： XIE Jianbing yuan Weizheng chang Honglong Micro and Nano Electromechanical Systems Laboratory Northwestern Polytechnical University Xi ＇an 710072 China

The mode coupling is a major factor to affect the precision of the micro electromechanical systems（MEMS） gyroscope. Currently, many MEMS gyroscopes with separate oscillation modes for drive and detection have been developed to decrease the mode coupling, but the gyroscope accuracy can not satisfy the high-precision demand well. Therefore, high performance decoupled MEMS gyroscopes is still a hot topic at present. An innovative design scheme for a MEMS gyroscope is designed, and in this design, the inertial mass is divided into three parts including the inner mass, the outer mass and the main frame mass. The masses are supported and separated by a set of mutually orthogonal beams to decouple their movements. Moreover, the design is modelled by multi-port-element network（MuPEN） method and the simulation results show that the mode coupling of the gyroscope between driving and sensing mode was eliminated effectively. Furthermore, we proposed a new silicon-on-insulator（SOI） process to fabricate the gyroscope. The scale factor of the fabricated gyroscope is 8.9 mV/（（~）os） and the quality factor（Q-factor） is as high as 600 at atmosphere pressure, and then, the resonant frequency, scale factor and bias drift has been test. Process and test results show that the proposed MEMS gyroscope are effective for decrease mode coupling, furthermore, it can achieve a high performance at atmosphere pressure. Furthermore, the MEMS gyroscope can achieve a high performance at atmosphere pressure. The research can be taken as good advice for the design and fabrication of MEMS gyroscope, meanwhile, it also provides technical support for speeding up of MEMS gyroscope industrialization.

关键词： micro electromechanical systems(MEMS) gyroscope silicon-on-insulator decoupled oscillation modes

Homography-guided stereo matching for wide-baseline image interpolation

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Computational Visual Media 2022年第1期8卷 119-133页

作者： yuan chang Congyi Zhang Yisong Chen Guoping Wang Peking University Beijing 100871China Beijiing Engineering Technology Research Center of Virtual Simulation and Visualization Peking UniversityBeijing 100871China The University of Hong Kong Hong KongChina

Image interpolation has a wide range of applications such as frame rate-up conversion and free viewpoint *** significant progresses,it remains an open challenge especially for image pairs with large *** this paper,we first propose a novel optimization algorithm for motion estimation,which combines the advantages of both global optimization and a local parametric transformation *** perform optimization over dynamic label sets,which are modified after each iteration using the prior of piecewise consistency to avoid local *** we apply it to an image interpolation framework including occlusion handling and intermediate image *** validate the performance of our algorithm experimentally,and show that our approach achieves state-of-the-art performance.

关键词： image interpolation view synthesis homo-graphy propagation belief propagation

A review on image-based rendering

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Virtual Reality & Intelligent Hardware 2019年第1期1卷 39-54页

作者： yuan chang Guo-Ping WANG School of Electronics Engineering and Computer Science Peking UniversityBeijing 100871China Beijing Engineering Research Center for Virtual Simulation and Visualization Beijing 100871China

Image-based rendering is important both in the field of computer graphics and computer vision,and it is also widely used in virtual reality *** more than two decades,people have done a lot of work on the research of image-based rendering,and these methods can be divided into two categories according to whether the geometric information of the scene is *** to this classification,we introduce some classical methods and representative methods proposed in recent *** also compare and analyze the basic principles,advantages and disadvantages of different ***,some suggestions are given for research directions on image-based rendering techniques in the future.

关键词： Image-based rendering Virtual reality Image interpolation Panorama

Qian Mu's Guoshi dagang: Reflections on a Modern Chinese Conservative

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Frontiers of History in China 2019年第3期14卷 385-426页

作者： yuan chang The Chinese Programme Nanyang Technological University48 Nanyang Drive639818Singapore

This paper examines the predicament of modem Chinese conservatism.I use the eminent historian Qian Mu(1895—1990)as an example to show that under the influence of modernity and in an effort to preserve tradition,a prominent conservative like Qian needed to“modernize”Chinese tradition so that it could be saved.I will examine Qian’s reconstruction of Chinese history,which was not just a reiteration of China’s past,but a new type of understanding of Chinese tradition influenced by modem Western *** focusing on Qian’s most prominent work,Guoshi dagang,we can get a sense of the struggle of modem Chinese conservatives as they tried to fend off the detractors of Chinese tradition.

关键词： Qian Mu Guoshi dagang tradition conservatism Chineseintellectual history

A review of microwave-induced thermoacoustic imaging:Excitation source,data acquisition system and biomedical applications

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Journal of Innovative Optical Health Sciences 2017年第4期10卷 52-69页

作者： Yongsheng Cui chang yuan Zhong Ji MOE Key Laboratory of Laser Life Science and Institute of Laser Life Science College of Biophotonics South China Normal University Guangzhou 510631P.R.China

Microwave-induced thermoacoustic imaging(TAI)is a noninvasive modality based on the differences in microwave absorption of various biological *** has been extensively researched in recent years,and several studies have revealed that TAI possesses advantages such as high resolution,high contrast,high imaging depth and fast imaging *** this paper,we reviewed the development of the TAI technique,its excitation source,data acquisition system and biomedical *** is believed that TAI has great potential applications in biomedical research and clinical study.

关键词： Thermoacoustic imaging microwave biomedical applications

Curcumin Inhibits Proliferation of Renal Cell Carcinoma in vitro and in vivo by Regulating miR-148/ADAMTS18 through Suppressing Autophagy

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Chinese Journal of Integrative Medicine 2023年第8期29卷 699-706页

作者： XU Ben yuan chang-wei ZHANG Jia-en Depatment of Urology Peking University First HospitalBeijing(100034)China

Objective: To explore the effect of curcumin on the proliferation of renal cell carcinoma and analyze its regulation mechanism. Methods: In RCC cell lines of A498 and 786-O, the effects of curcumin(2.5, 5, 10 μmo/L) on the proliferation were analyzed by Annexin V+PI staining. Besides, A498 was inoculated into nude mice to establish tumorigenic models, and the model mice were treated with different concentrations of curcumin(100, 200, and 400 mg/kg), once daily for 30 days. Then the tumor diameter was measured, the tumor cells were observed by hematoxylin-eosin staining, and the protein expressions of miR-148 and ADAMTS18were detected by immunohistochemistry. In vitro, after transfection of miR-148 mimics, miR-148 inhibitor or si-ADAMTS18 in cell lines, the expression of ADAMTS18 was examined by Western blotting and the cell survival rate was analyzed using MTT. Subsequently, Western blot analysis was again used to examine the autophagy phenomenon by measuring the relative expression level of LC3-Ⅱ/LC3-Ⅰ;autophagy-associated genes,including those of Beclin-1 and ATG5, were also examined when miR-148 was silenced in both cell lines with curcumin treatment. Results: Curcumin could inhibit the proliferation of RCC in cell lines and nude mice. The expressions of miR-148 and ADAMTS18 were upregulated after curcumin treatment both in vitro and in vivo(P<0.05). The cell survival rate was dramatically declined upon miR-148 or ADAMTS18 upregulated. However,si-ADAMTS18 treatment or miR-148 inhibitor reversed these results, that is, both of them promoted the cell survival rate. Conclusion: Curcumin can inhibit the proliferation of renal cell carcinoma by regulating the miR-148/ADAMTS18 axis through the suppression of autophagy in vitro and in vivo. There may exist a positive feedback loop between mi R-148 and ADAMTS18 gene in RCC.

关键词： curcumin renal cell carcinoma MiR-148 ADAMTS18 gene autophagy

Parameter Dependence of Stable Manifolds for Nonuniform (μ, ν)-dichotomies

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Acta Mathematica Sinica,English Series 2013年第6期29卷 1111-1130页

作者： Ji Min ZHANG Meng FAN Xiao yuan chang College of Mathematics Jilin University School of Mathematical Sciences Heilongjiang University School of Mathematics and Statistics Northeast Normal University School of Applied Sciences Harbin University of Science and Technology

We construct stable invariant manifolds for semiflows generated by the nonlinear impulsive differential equation with parameters x＇= A（t）x ＋ f（t, x, λ）, t≠τi and x（τ＋i） = Bix（τi）＋ gi（x（τi）, λ）, i ∈ N in Banach spaces, assuming that the linear impulsive differential equation x＇= A（t）x, t≠τi and x（τ＋i） = Bix（τi）, i ∈ N admits a nonuniform （μ, ν）-dichotomy. It is shown that the stable invariant manifolds are Lipschitz continuous in the parameter λ and the initial values provided that the nonlinear perturbations f, g are sufficiently small Lipschitz perturbations.

关键词： Stable invariant manifolds nonuniform ( μ ν )-dichotomies impulsive differential equations

Plantation transformation alternatives determine carbon sequestration capacity – a case study with Pinus massoniana in southern China

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Journal of Mountain Science 2020年第4期17卷 919-930页

作者： RUAN Lu-ping LU yuan-chang MENG Jing-hui Research Center of Forest Management Engineering of National Forestry and Grassland Administration Beijing Forestry UniversityBeijing 100083China Institute of Forest Resource and Information Techniques Chinese Academy of ForestryBeijing 100091China

It is widely accepted that global warming, which results from the increase of carbon dioxide(CO2) in the atmosphere, has a negative impact on human beings. Forests are the largest terrestrial ecosystem and play an important role in carbon sequestration. Many studies have documented that a mixed-species forest can sequester more carbon than single species forests, depending on the site conditions. Therefore, uneven-aged mixed-species forest management has been receiving more and more attention. In 2008, an experiment with five silvicultural models for Pinus massoniana(Chinese red pine) plantation, i.e., four transformation treatments(A1-A4) and one control treatment(A5) was conducted in the Experimental Center of Tropical Forestry of Chinese Academy of Forestry in Pingxiang City, in southwestern Guangxi Zhuang Autonomous Region, southern China. The four transformation treatments(A1-A4) enriched Castanopsis hystrix, Manglietia glance, Erythrophleum fordii and Quercus griffithii with differed richness and composition after thinning(removed 70% of trees), while no silvicultural treatment was used in the control treatment A5. In this study, we compared the carbon sequestration capacity of these five silvicultural models based on periodic annual increment and growth rate. Our results indicated that all the transformation treatments performed significantly better in carbon sequestration than the control treatment. A significant difference was also observed amongst the transformation treatments. Moreover, the transformation treatment A1 with enrichment species Castanopsis hystrix(350 trees·ha^-1) and Manglietia glance(350 trees·ha^-1) was determined to be the optimal model for maximum carbon sequestration because of its high tree-level growth rate and high economic value of enriched plantings, which could be popularized in other places. Our results further confirmed that management using mixed-species forests is a better approach to combat climate change than using monocult

关键词： Global warming Carbon sequestration Mixed-species forest Silvicultural model Singlespecies(monoculture)forest

Two new prenylflavonoids from Epimedium sutchuenense

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Chinese Chemical Letters 2009年第7期20卷 842-844页

作者： chang yuan Yu Li Na Song Guang Chen College of Life Science and Technology Beijing University of Chemical Technology Beijing 100029 China

Two new prenylflavonoids, named sutchuenmedin A （1） and sutchuenmedin B （2）, were isolated from the 70% EtOH extract of Epimedium sutchuenense. Their structures were determined from spectral analysis. C 2009 Guang... 详细信息

关键词： Epimedium sutchuenense Flavonoids Sutchuenmedin A Sutchuenmedin B