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Chinese Journal of Structural Chemistry 2018年第7期37卷 1037-1044页

作者： Fuzhou 350007 China） College of Chemistry and Materials Science Fujian Normal University College of Electronics and Information Science Fujian Jiangxia University State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Using density functional theory（DFT） combined with nonequilibrium Green＇s function investigates the electron-transport properties of several molecular junctions based on the PBTDT-CH=NH molecule, which is modified by one to four alkyl groups forming PBTDT-（CH2）nCH=NH. The electronic structures of the isolated molecules（thiol-ended PBTDT-（CH2）nCH=N） have been investigated before the electron-transport calculations are performed. The asymmetric current-voltage characteristics have been obtained for the molecular junctions. Rectifying performance of Au/S-PBTDT-CH=N-S/Au molecular junction can be regulated by introducing alkyl chain. The N3 molecular junction exhibits the best rectifying effect. Its maximum rectifying ratio is 878, which is 80 times more than that of the molecular junction based on the original N molecular junction. The current-voltage（I-V） curves of all the sandwich systems in this work are illustrated by transmission spectra and molecular projection density analysis.

关键词： the first principle phenyl benzothiophene alkyl chain rectification

Sliding mode robust controller for automatic rectification of shield machine

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Journal of Central South University 2011年第2期18卷 536-541页

作者：岳明孙伟魏建 School of Automotive Engineering Dalian University of Technology School of Mechanical Engineering Dalian University of Technology

According to the actual engineering problem that the precise load model of shield machine is difficult to achieve,a design method of sliding mode robust controller oriented to the automatic rectification of shield machine was proposed. Firstly,the nominal load model of shield machine and the ranges of model parameters were obtained by the soil mechanics parameters of certain geological conditions and the messages of the self-learning of shield machine by tunneling for previous segments. Based on this rectification mechanism model with known ranges of parameters,a sliding mode robust controller was proposed. Finally,the simulation analysis was developed to verify the effectiveness of the proposed controller. The simulation results show that the sliding mode robust controller can be implemented in the attitude rectification process of the shield machine and it has stronger robustness to overcome the soil disturbance.

关键词： shield machine rectification sliding mode robust upper bound

A valveless piezoelectric pump with novel flow path design of function of rectification to improve energy efficiency

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Frontiers of Mechanical Engineering 2022年第3期17卷 177-193页

作者： Jianhui ZHANG Xiaosheng CHEN Zhenlin CHEN Jietao DAI Fan ZHANG Mingdong MA Yuxuan HUO Zhenzhen GUI School of Mechanical and Electrical Engineering Guangzhou UniversityGuangzhou510006China

Existing valveless piezoelectric pumps are mostly based on the flow resistance mechanism to generate unidirectional fluid pumping,resulting in inefficient energy conversion because the majority of mechanical energy is consumed in terms of parasitic *** this paper,a novel tube structure composed of a Y-shaped tube and aȹ-shaped tube was proposed considering theory of jet inertia and vortex dissipation for the first time to improve energy *** verifying its feasibility through the flow field simulation,the proposed tubes were integrated into a piezo-driven chamber,and a novel valveless piezoelectric pump with the function of rectification(NVPPFR)was *** previous pumps,the reported pump directed the reflux fluid to another flow channel different from the pumping fluid,thus improving pumping ***,mathematical modeling was established,including the kinetic analysis of vibrator,flow loss analysis of fluid,and pumping ***,experiments were designed,and results showed that NVPPFR had the function of rectification and net pumping *** maximum flow rate reached 6.89 mL/min,and the pumping efficiency was up to 27%.The development of NVPPFR compensated for the inefficiency of traditional valveless piezoelectric pumps,broadening the application prospect in biomedicine and biology fields.

关键词： composite tube valveless piezoelectric pump rectification energy efficiency

First Principle Study on the rectification of Molecular Junctions Based on the Thiol-ended Oligosilane

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Chinese Journal of Structural Chemistry 2015年第6期34卷 813-821页

作者： ZHANG Rong-Fang YANG E LI Yi LIN Li-Xiang LING Qi-Dana College of Materials Science & Engineering Fujian Normal University College of Chemistry Fuzhou University

The electron transport properties of various molecular junctions based on the thiol-ended oligosilane are investigated through density functional theory combined with non-equilibrium Green＇s function formalism. Our calculations show that oligosilanes doped by the phenyl and -C10H6 groups demonstrate better rectifying effect and their rectification ratios are up to 15.41 and 65.13 for their molecular junctions. The current-voltage （I-V） curves of all the Au/ modified oligosilane/Au systems in this work are illustrated by frontier molecular orbitals, transmission spectra and density of states under zero bias. And their rectifying behaviors are analyzed through transmission spectra.

关键词： first principle thiol-ended oligosilane rectification

Modeling and rectification of Rolling Shutter Effect in CMOS Aerial Cameras

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Journal of Harbin Institute of Technology(New Series) 2017年第4期24卷 71-77页

作者： Lei Wan Ye Zhang Ping Jia Jiajia Xu Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Science Graduate School of the Chinese Academy of Science Key Laboratory of Airborne Optical Imaging and Measurement Chinese Academy of Science

Due to the electronic rolling shutter, high-speed Complementary Metal-Oxide Semiconductor( CMOS) aerial cameras are generally subject to geometric distortions,which cannot be perfectly corrected by conventional vision-based algorithms. In this paper we propose a novel approach to address the problem of rolling shutter distortion in aerial imaging. A mathematical model is established by the coordinate transformation method. It can directly calculate the pixel distortion when an aerial camera is imaging at arbitrary gesture *** all pixel distortions form a distortion map over the whole CMOS array and the map is exploited in the image rectification process incorporating reverse projection. The error analysis indicates that within the margin of measuring errors,the final calculation error of our model is less than 1/2 pixel. The experimental results show that our approach yields good rectification performance in a series of images with different distortions. We demonstrate that our method outperforms other vision-based algorithms in terms of the computational complexity,which makes it more suitable for aerial real-time imaging.

关键词： aerial camera CMOS sensor rolling shutter effect coordinate transformation image rectification

A simple rectification method for linear multi-baseline stereovision system

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Journal of Zhejiang University Science 2004年第5期5卷 567-571页

作者：杜歆李宏东顾伟康 DepartmentofInformationandElectronics ZhejiangUniversityHangzhou310027China DepartmentofInformationandElectronics ZhejiangUniversityHangzhou310027China

The linear multi-baseline stereo system introduced by the CMU-RI group has been proven to be a very effective and robust stereovision system. However, most traditional stereo rectification algorithms are all designed for binocular stereovision system, and so, cannot be applied to a linear multi-baseline system. This paper presents a simple and intuitional method that can simultaneously rectify all the cameras in a linear multi-baseline system. Instead of using the general 8-parameter homography transform, a two-step virtual rotation method is applied for rectification, which results in a more specific transform that has only 3 parameters, and more stability. Experimental results for real stereo images showed the presented method is efficient.

关键词： rectification Multi-baseline Stereovision

Photoacoustic imaging with attenuation rectification of different frequent components of photoacoustic signal

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Photoacoustic imaging with attenuation rectification of diff...

Selective Image Matting with Scalable Variance and Model rectification

Photonics Asia 2004;Sensors and Imaging

作者： Yi Tan, Da Xing*, Yi Wang and Diwu Yang Institute of Laser Life Science, South China Normal University, Guangzhou 510631, China

Photoacoustic tomography is a potential and noninvasive medical imaging technology. It combines the advantages of pure optic imaging and pure ultrasound imaging. Photoacoustic signals induced by a sho

关键词： photoacoustic imaging photoacoustic signal attenuation rectification

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国际计算机前沿大会会议论文集 2017年第1期 134-138页

作者： Xiao Chen Fazhi He Yiteng Pan Haojun Ai School of Computer Science Wuhan UniversityWuhan 430072China

Bayesian Matting has four ***,Bayesian matting makes strong assumption that the texture distribution of nature image satisfies Gaussian distribution with fixed *** assumption will fail for complex texture *** order to extract the nature images with complex texture distribution,we design an information entropy approach to estimate the scalable ***,when the opacity is near the boundary of the value range,Bayesian matting method may be failure because of the error computation of ***,a rectification approach is proposed to adjust the computation model and keep the opacity within the valid value ***,Bayesian matting is a local sample method which may miss some valid samples of *** propose a selection function to integrate valid global sample matting result into above matting framework as a supplement to the local sample matting *** proposed function is compose of three criteria,that is,the similarity of results,the overlapping degree of samples,and the similarity of ***,in order to obtain a smooth and vivid matte,the result is further refined by considering correlation between neighbouring ***,We use online benchmark for image matting to evaluate the proposed method with both qualitative observation and quantitative *** experiments show that our method achieves a competitive advantages over other methods.

关键词： Image matting Information entropy Model rectification Constraint optimization Global sample Selection function

The First Principle Study on the rectification of Molecular Junctions Based on the Alkyl-chain-modified Phenyl Benzothiophene Derivative

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基于室温铁磁性的(Fe,Al)共掺杂SiGe铁磁pn二极管的可调整流和磁阻特性

结构化学 2018年第7期 1037-1044页

作者： CHENZhi-Peng ZHANGYa-Mei GUOZhen-Gang LINLi-Xiang YANGE LINGQi-Dan College of Chemistry and Materials Science，Fujian Normal University College of Electronics and Information Science，Fujian Jiangxia University State Key Laboratory of Structural Chemistry，Fujian Institute of Research on the Structure of Matter，Chinese Academy of Sciences

Using density functional theory（DFT） combined with nonequilibrium Green’s function investigates the electron-transport properties of several molecular junctions based on the PBTDT-CH=NH molecule, which is modified by one to four alkyl groups forming PBTDT-（CH2）nCH=NH. The electronic structures of the isolated molecules（thiol-ended PBTDT-（CH2）nCH=N） have been investigated before the electron-transport calculations are performed. The asymmetric current-voltage characteristics have been obtained for the molecular junctions. Rectifying performance of Au/S-PBTDT-CH=N-S/Au molecular junction can be regulated by introducing alkyl chain. The N3 molecular junction exhibits the best rectifying effect. Its maximum rectifying ratio is 878, which is 80 times more than that of the molecular junction based on the original N molecular junction. The current-voltage（I-V） curves of all the sandwich systems in this work are illustrated by transmission spectra and molecular projection density analysis.

关键词： the first principle phenyl benzothiophene alkyl chain rectification

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Science China Materials 2024年第2期67卷 573-579页

作者：李加飞张析向钢 College of Physics Sichuan UniversityChengdu 610064China

Ⅳ族稀磁半导体因其优异的磁电性能,以及在与当前主流半导体集成技术兼容的自旋电子器件中具有广阔的应用前景而受到越来越多的关注.事实上,具有室温铁磁性的Ⅳ族稀磁半导体及其衍生器件更有望在实际中得以应用.本工作设计并制备了基于p... 详细信息

Ⅳ族稀磁半导体因其优异的磁电性能,以及在与当前主流半导体集成技术兼容的自旋电子器件中具有广阔的应用前景而受到越来越多的关注.事实上,具有室温铁磁性的Ⅳ族稀磁半导体及其衍生器件更有望在实际中得以应用.本工作设计并制备了基于p型(Fe,Al)共掺杂SiGe薄膜和n型Ge衬底的磁性pn二极管.磁性测量以及磁阻和反常霍尔效应测试揭示了p型(Fe,Al)共掺杂SiGe薄膜的室温铁磁性.有趣的是,磁性pn异质结表现出磁场可调的整流和磁阻行为.我们的研究结果为制备具有室温铁磁性的Ⅳ族稀磁半导体提供了一种可选策略,并为Ⅳ族稀磁半导体的实际自旋电子应用提供了范例.

关键词： diluted magnetic semiconductor SiGe pn junction rectification magnetoresistance