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Combination Effect of Cation Vacancies and O2 Adsorption on Ferromagnetism of Na0.5Bi0.5TiO3（100） Surface:ab initio Study

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Chinese Journal of Chemical Physics 2018年第2期31卷 177-183,245页

作者： Lin Ju Ying Dai Tong-shuai Xu Yong-jia Zhang Li Sun School of Physics and Electric Engineering Anyang Normal University Anyang 455000 China School of Physics State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of Technology Taiyuan 030024 China

The combination effect of cation vacancies and O2 adsorption on ferromagnetism of Na0.5Bi0.5TiO3（100） surface is studied by using density functional theory. An ideal Na0.5Bi0.5TiO3（100） surface is non-magnetic and the cation vacancy could induce the magnetism. By comparing the formation energies for Na, Bi and Ti vacancy, the Na vacancy is more stable than the others. Therefore, we focus on the configuration and electric structure for the system of O2 molecule adsorption on the Na0.5Bi0.5TiO3（100） surface with a Na vacancy. Among the five physisorption configurations we considered, the most likely adsorption position is Na vacancy. The O2 adsorption enhances the magnetism of the system. The contribution of spin polarization is mainly from the O 2p orbitals. The characteristics of exchange coupling are also calculated, which show that the ferromagnetic coupling is favorable. Compared with the previous calculation results, our calculations could explain the room-temperature ferromagnetism of Na0.5Bi0.5TiO3 nanocrytalline powders more reasonably, because of taking into account adsorbed oxygen and cation vacancies. Moreover, our results also show that adsorption of O2 molecule as well as introduction of cation vacancies may be a promising approach to improve multiferroic materials.

关键词： O2 adsorption Cation vacancies Ferromagnetism First-principles calculation

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Reliability Analysis of Manufacturing Machine with Degradation and Low-quality Feedstocks

Reliability Analysis of Manufacturing Machine with Degradati...

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Advanced Reliability and Maintenance Modeling (APARM), Asia-Pacific International Symposium on

作者： Zhenggeng Ye Zhiqiang Cai Hui Yang Department of Industrial Engineering Northwestern Polytechnical University Xi’an China School of Mechanical Engineering Northwestern Polytechnical University Xi’an P.R. China Ministry of Industry and Information Technology Key Laboratory of Industrial Engineering and Intelligent Manufacturing Northwestern Polytechnical University Xi’an P.R. China Complex Systems Monitoring Modeling and Control Laboratory in the Harold Pennsylvania State University (University Park) State College PA USA The Harold and Inge Marcus Department of Industrial and Manufacturing Engineering The Pennsylvania State University (University Park) State College USA Department of Industrial and Manufacturing Engineering Pennsylvania State University (University Park) State College PA USA

ISBN: (数字)9781728171029

ISBN: (纸本)9781728171036

Machine reliability is one major concern in manufacturing industries, which is affected by interior degradation and outside shocks simultaneously. Low-quality feedstocks, as one typical kind of shocks, may arrive randomly during the operation of a machine. However, due to the instability of environment and manufacturing factors, low-quality feedstocks may arrive in clusters in some specific batches. In this paper, we first proposed a reliability evaluation model for the repairable machine, accounting for machine degradation and shocks caused by low-quality feedstocks. Then, the cluster arrival of low-quality feedstocks is modeled by the Hawkes point process with the properties of self-exciting and history dependent. Moreover, considering the degradation and shocks, the mixture failure rate of a machine is modeled. Further, the expectation of remaining lifetime is derived. Finally, the simulation experiment is implemented to compare the performance between the machine when the arrival intervals of low-quality feedstocks follow the Poisson point process and the Hawkes point process. Experimental results show the effectiveness of the proposed model for machine reliability analysis.

关键词： Electric shock Degradation Maintenance engineering Mathematical model Manufacturing Reliability engineering

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Cooperative Lane Change Motion Planning of Connected and Automated Vehicles: A Stepwise Computational Framework

Cooperative Lane Change Motion Planning of Connected and Aut...

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2018 IEEE intelligent Vehicles Symposium, IV 2018

作者： Zhang, Youmin Li, Bai Zhang, Yue Jia, Ning Shaanxi Key Laboratory of Complex System Control and Intelligent Information Processing Xi'An University of Technology Xi'an710048 China Division of Systems Engineering Center for Information and Systems Engineering Boston University Boston United States Department of Mechanical Industrial and Aerospace Engineering Concordia Institute of Aerospace Design and Innovation Concordia University Montreal Canada Institute of Systems Engineering Tianjin University Tianjin China

ISBN: (纸本)9781538644522

This paper focuses on the scheme of cooperative lane change motion planning of multiple connected and automated vehicles, so as to minimize the time for lane change while penalizing large steering angles subject to hard collision avoidance constraints. Nominally this scheme should be formulated in a centralized way with the constraints of all the vehicles considered simultaneously. In order to facilitate the numerical solving process of this centralized optimization problem, we propose a stepwise computation framework. Starting with a sub-problem with all of the collision avoidance constraints removed, a sequence of sub-problems are defined by adding back the removed collision avoidance constraints gradually until the original problem takes shape in the end. The optimum of one sub-problem is always used as the initial guess when solving the next sub-problem. This iterative process continues until the optimum of the original problem is obtained. In this way, the difficulties in the original centralized problem are divided into multiple parts, and every progress made to address the partial difficulties is 'solidified' by the initial guess. © 2018 IEEE.

关键词： Collision avoidance

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A 3D Display Parallel system: Light Field Re-rendering and Depth Sense Optimization

A 3D Display Parallel System: Light Field Re-rendering and D...

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International Conference on Display Technology, ICDT 2018

作者： Pei, Renjing Ma, Kui Wang, Feiyue State Key Laboratory of Management and Control for Complex Systems Institute of Automation Chinese Academy of Sciences East Zhongguanchun Road No. 95 Haidian District Beijing China School of Computer and Control Engineering University of Chinese Academy of Sciences Beijing China Parallel Optics Technology Innovation Center Qingdao Academy of Intelligent Industries Qingdao China

ISBN: (纸本)9781510867659

The main benefit of 3D display over 2D display is the obvious ability to create a more lifelike character with high depth sense. However, the limitation of human eye’s visual mechanism, unartful 3D scene structure design, or bad viewing condition always emerges poor depth perception experience or even physiological discomfort during the watching time, which is often sub-optimal for mass high-quality 3D display productions. To solve this problem, we propose a novel 3D display parallel system for depth sense optimization and it empirically guides how the light field should be re-rendered. Structurally, the parallel system consists of an artificial perception measurement system, a display evaluation model and a light field display rendering system, which includes the display calibration, scene capture, light field data processing and display. Particularly, the system can systematically analyze and model various factors affecting the depth sense which learned through the measurement system, like scene structure, objects’ speeds in 3D video and so on. And those sense factors can be personally modified or increased according to the viewer’s demands or technical improvement. Moreover, the light field could be real-time re-rendered, based on some image processing technology, optical flow analysis and object segmentation (or tracking) (especially the one-shot video segmentation). Theory and algorithms are developed and experimental validation results show a superior performance. © 2018 SID.

关键词： Three dimensional displays

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A high-precision vision-based mobile robot slope detection method in unknown environment

A high-precision vision-based mobile robot slope detection m...

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Chinese Automation Congress

作者： Kenan Du Jing Xin Yaqian Shi Ding Liu Youmin Zhang CETC 20 Shaanxi key Laboratory of Integrated and Intelligent Navigation Xi'an P.R. China Shaanxi Key Laboratory of Complex System Control and Intelligent Information Processing Xi‘an University of Technology Xi'an P.R. China Department of Mechanical and Industrial Engineering Concordia University Quebec Canada

Aiming at satisfying the demand of slope perception accuracy for mobile robots in the unknown environment, a high-precision vision-based mobile robot slope detection method in unknown environment is proposed in this paper. Firstly, the RGB images of slopesin the unknown environment arecaptured by the Kinect sensor installed on the mobile robot, and edge sharpening is performed on the images of slopes. Then, the coordinates of the slope edge pixel in the image coordinate system are transformed into the camera coordinate system to obtain the real length of the slope. Finally, the single image depth estimation method based on convolution neural network (CNN) is used to estimate the depth of theslope image toobtain the projection length of the slope only using a single slope image, and the slope angle is obtained by the inverse cosine function. The experimental results show that the slope detection method proposed in this paper has higher detection accuracy and can satisfy the demand of slope sensing accuracy of mobile robot in unknown environment.

关键词： Slope detection Coordinate transformation Single image Depth estimation Convolutional neural network (CNN)

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Synchronization of fractional-order gene regulatory network with delay 36

Synchronization of fractional-order gene regulatory network ...

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第36届中国控制会议

作者： Feng Liu Zhe Zhang Ren Jie Sun Fenglan School of Automation China University of Geosciences Hubei key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Research Center of System Theory & Application Chongqing University of Posts and Telecommunications

ISBN: (纸本)9781538629185

This paper investigates the problem of Synchronous control of Fractional gene regulatory *** on the Lyapunov stability judgment method,we apply two kinds of control method,adaptive projection control and adaptive sliding mode control,for making system ***,a numerical simulation example is provided to verify the effectiveness and the benefit of the proposed synchronicity criterion.

关键词： Fractional-order synchronization adaptive projection control adaptive sliding mode control

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Noninvasive super-resolution imaging through scattering media

arXiv

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arXiv 2019年

作者： Wang, Dong Sahoo, Sujit Kumar Dang, Cuong Nanyang Technological University Singapore 50 Nanyang Avenue 639798 Singapore Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education Shanxi Province College of Physics and Optoelectronics Taiyuan University of Technology Taiyuan030024 China School of Electrical Sciences Indian Institute of Technology Goa Goa 403401 India

Super-resolution imaging with advanced optical systems has been revolutionizing technical analysis in various fields from biological to physical sciences. However, many objects are hidden by strongly scattering media such as rough wall corners or biological tissues that scramble light paths, create speckle patterns and hinder object’s visualization, let alone super-resolution imaging. Here, we realize a method to do non-invasive super-resolution imaging through scattering media based on stochastic optical scattering localization imaging (SOSLI) technique. Simply by capturing multiple speckle patterns of photo-switchable emitters in our demonstration, the stochastic approach utilizes the speckle correlation properties of scattering media to retrieve an image with more than five-fold resolution enhancement compared to the diffraction limit, while posing no fundamental limit in achieving higher spatial resolution. More importantly, we demonstrate our SOSLI to do non-invasive super-resolution imaging through not only optical diffusers, i.e. static scattering media, but also biological tissues, i.e. dynamic scattering media with decorrelation of up to 80%. Our approach paves the way to non-invasively visualize various samples behind scattering media at unprecedented levels of detail. Copyright © 2019, The Authors. All rights reserved.

关键词： Stochastic systems

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Design and Application of a Web-based Comprehensive Evaluation and Decision Support system for Tobacco Cultivation Process

Design and Application of a Web-based Comprehensive Evaluati...

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第37届中国控制会议

作者： Gong Chen Yonghua Xiong Wei Chen Hao Zhou School of Automation China University of Geoscience Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Guizhou Tobacco Science Institute

The evaluation and decision support system are widely used in agriculture with the development of information technology. In this paper, a Web-based comprehensive evaluation and decision support system（WCEDSS） is designed for flue-cured tobacco cultivation process. Using the artificial neural networks and some image processing methods, WCEDSS can predict various indicators of tobacco such as yield and flue-cured score, or give decisions at different stages of tobacco cultivation. As the system is developed by the Browser/Server（B/S） architecture, it is possible to make full use of the Internet resources and to facilitate users at any place with access to the Internet. Test results indicates that WCEDSS can achieve good performance. With other auxiliary functions, the system shows potential and extensive practicality in agricultural information management and guidance.

关键词： tobacco Browser/Server architecture evaluate decision support

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Damage evaluation model and simulation study on functional systems of ultra low altitude aircraft 32

Damage evaluation model and simulation study on functional s...

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32nd Youth Academic Annual Conference of Chinese Association of Automation, YAC 2017

作者： Xiaochen, Wu Chen, Chen School of Automation Beijing Institute of Technology Beijing100081 China Key Laboratory of Complex System Intelligent Control and Decision Ministry of Education Beijing100081 China

ISBN: (纸本)9781538629017

The assessment of aircraft damage is a key technology in modern flight missions. For a kind of ultra low altitude aircraft, simulation study of the damage caused by the prefabricated fragments is carried out, which is based on the functional systems contained in the different components of the aircraft. In addition, the corresponding aircraft damage assessment simulation system is developed, which can complete the real-time damage calculation and quantify and classify the damage degree of the functional system. A new modeling idea and important research platform is provided for vulnerability assessment and damage assessment of specific targets. © 2017 IEEE.

关键词： Aircraft

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Design of High-Gain-Observer-Based State Feedback controller for Positive Time-Delay system

Design of High-Gain-Observer-Based State Feedback Controller...

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Chinese control Conference

作者： Mingyuan Xie Jinhua She Zhentao Liu Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Wuhan China School of Engineering Tokyo University of Technology Tokyo Japan

This paper investigates the stabilizability of positive time-delay system. The nonnegative constraint makes the design of a control law different from a general system. Firstly, a method to calculate the L_1 gain of a positive time-delay system is presented. Then, the design of a state feedback controller and a high-gain observer is presented by taking full advantage of the characteristics of the positiveness of the system. Finally, the observer and feedback controller are combined to stabilize the system and improve dynamic performance. A numerical example illustrates the provided method is effective.

关键词： Observers State feedback Delays Closed loop systems Adaptive control Delay effects

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