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Infrared Indoor Wireless MIMO Communication System Using 1.2GHz OOK Modulation

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China Communications 2019年第5期16卷 62-69页

作者： hao du Guoning Xu Academy of Opto-Electronics Chinese Academy of Sciences

The multiple input multiple output(MIMO) systems using serial infrared(SIR),return to zero-inverted(RZI) and on off keying(OOK) modulation were studied. Also, by analyzing experimental results, curve fitting models were established. Three infrared MIMO systems with 2X2, 2X4 and 4X4 MIMO channels using RZI and OOK modulation were designed and tested. Based on the experimental results, evaluations between BER, distance and displacement were discussed.

关键词： infrared communication MIMO system line of sight(LOS) RZI OOK modulation

Doped-TiO_2 Photocatalysts and Synthesis Methods to Prepare TiO_2 Films

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Journal of Materials Science & Technology 2008年第5期24卷 675-689页

作者： Ying GUI hao du Lishi WEN Division of Surface Engineering of Materials Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Graduate School of Chinese Academy of Sciences： Beijing 100039 China

TiO2 is a promising photocatalyst. However, the low photocatalytic efficiency calls for the modification of TiO2. Metal- and nonmetal-doping of TiO2 have been proved to be effective ways to enhance photocatalytic properties. This review provides a deep insight into the understanding of the metal- and nonmetal-doped TiO2 photocatalysts. This article begins with the introduction of the crystal structures of TiO2 and applications of TiO2 materials. We then reviewed the doped-TiO2 system in two categories：（1） metal-doped TiO2 photocatalysts system, and （2） nonmetal-doped TiO2 photocatalysts system. Both experimental results and theoretical analyses are elaborated in this section. In the following part, for the advantages of TiO2 thin films over particles, various preparation methods to obtain TiO2 thin films are briefly discussed. Finally, this review ends with a concise conclusion and outlook of new trends in the development of TiO2-based photocatalysts.

关键词： TiO2 films Photocatalysis Metal-doping Nonmetal-doping DFT

Autonomous landing scene recognition based on transfer learning for drones

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Journal of Systems Engineering and Electronics 2023年第1期34卷 28-35页

作者： du hao WANG Wei WANG Xuerao WANG Yuanda School of Automation Southeast UniversityNanjing 210096China Autonomous Control Robot Laboratory Jiangsu Zhongke Institute of Applied Research on Intelligent Science and TechnologyChangzhou 213164China Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing University of Information Science and TechnologyNanjing 210044China

In this paper, we study autonomous landing scene recognition with knowledge transfer for drones. Considering the difficulties in aerial remote sensing, especially that some scenes are extremely similar, or the same scene has different representations in different altitudes, we employ a deep convolutional neural network(CNN) based on knowledge transfer and fine-tuning to solve the problem. Then, LandingScenes-7 dataset is established and divided into seven classes. Moreover, there is still a novelty detection problem in the classifier, and we address this by excluding other landing scenes using the approach of thresholding in the prediction stage. We employ the transfer learning method based on ResNeXt-50 backbone with the adaptive momentum(ADAM) optimization algorithm. We also compare ResNet-50 backbone and the momentum stochastic gradient descent(SGD) optimizer. Experiment results show that ResNeXt-50 based on the ADAM optimization algorithm has better performance. With a pre-trained model and fine-tuning, it can achieve 97.845 0% top-1 accuracy on the LandingScenes-7dataset, paving the way for drones to autonomously learn landing scenes.

关键词： landing scene recognition convolutional neural network(CNN) transfer learning remote sensing image

Effects of Power Density and Post Annealing Process on the Microstructure and Wettability of TiO_2 Films Deposited by Mid-frequency Magnetron Reactive Sputtering

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Journal of Materials Science & Technology 2008年第2期24卷 172-178页

作者： Ying CUI hao du Jinquan XIAO Lishi WEN Division of Surface Engineering of Materials Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

The relationship of ＂preparation parameters-microstructures-wettability＂ of TiO2 films was reported. In this work, TiO2 films were deposited onto glass and silicon substrates by using mid-frequency dual magnetron sputtering technique at ambient temperature with various power densities and deposition time. After deposition, the films were heat treated at different annealing temperatures. X-ray diffraction （XRD）, Raman spectroscopy, and field-emission scanning electron microscopy （FE-SEM） were utilized to characterize TiO2 films. The wettability of the films was evaluated by water contact angle measurement. The phase transition temperature of TiO2 films depended on the power density. It was demonstrated that wettability was strongly structure dependent and the film with the thickness of 610 nm （the power density was 2.22 W/cm^2） showed the lowest contact angle （8°）. It can be concluded that smaller crystallite size, the rutile phase with （110） face being parallel to the surface, and tensile stress favored the hydrophilicity of the TiO2 films.

关键词： Titanium dioxide Reactive magnetron sputtering Phase composition Microstructure Hydrophilicity

Evolution Behaviors of Oxides in Severely Plastic Deformed Region of AISI 52100 Steel during Dry Sliding Wear

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Journal of Materials Science & Technology 2017年第4期33卷 330-337页

作者： Yuanxia Lao hao du Tianying Xiong Yuan Wang Key Laboratory of Radiation Physics and Technology Ministry of EducationInstitute of Nuclear Science and TechnologySichuan University Division of Surface Engineering of Materials Institute of Metal ResearchChinese Academy of Sciences

Under dry sliding wear, the evolution of oxides in severely plastic deformed（SPD） regions of metals has a great impact on the wear behaviors. To study the evolution behaviors of oxides in the SPD region, an SPD region was prefabricated on the surface of AISI 52100 steel by supersonic fine particle bombarding（SFPB） treatment. Dry sliding wear tests were carried out on both of the SFPB-treated and original *** volume loss of the SPBF-treated samples were compared with those of the original samples at different loads. Microstructure, element composition and oxides distribution in the SPD region were characterized by scanning electron microscopy（SEM）, transmission electron microscopy（TEM） and an electron probe microanalysis（EPMA）. The results show that the evolution behaviors of the oxides in the SPD region change significantly with the load. Under low loads, oxides are usually formed on the contact surface. It inhibits adhesive wear on the steel. However, under high loads, oxides are apt to distribute along the cracks in the subsurface layer. The internal oxidation along the cracks can accelerate the cracks propagation, resulting in severe delamination wear on the steel.

关键词： Sliding wear Plastic deformation Oxides Defects Steel

Cleaner production of 3.5 valent vanadium electrolyte from ammonium metavanadate by ammonia reduction-sulfuric acid dissolution method

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Tungsten 2024年第3期6卷 555-560页

作者： Cheng Wang Lan-Jie Li hao du College of Chemical Engineering University of Chinese Academyof SciencesBeijing100049China Institute of Process Engineering National Engineering Research Center of Green Recycling for Strategic Metal ResourcesChinese Academy of SciencesBeijing 100190China Hesteel Group Company Limited Shijiazhuang 050023China

The vanadium redox flow battery(VRFB)has been widely used in large-scale energy storage areas due to the advantages of long lifespan and high ***,the high preparation cost of vanadium electrolyte limits the largescale... 详细信息

关键词： vanadium electrolyte Clean

Low-frequency damping behavior of closed-cell Mg alloy foams reinforced with SiC particles

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International Journal of Minerals,Metallurgy and Materials 2017年第6期24卷 701-707页

作者： Wen-zhan Huang Hong-jie Luo Yong-liang Mu hao Lin hao du School of Metallurgy Northeastern University Shenyang 110819 China Engineering Research Center of the Ministry of Education for Advanced Materials Preparation Technology Shenyang 110819 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The damping properties of an Mg alloy foam and its composite foams were investigated using a dynamic mechanical thermal analyzer. The results show that the loss factors of both the Mg alloy and its composite foams are insensitive to temperature and loading frequency when the temperature is less than a critical temperature Tcrit. However, it increases when the temperature exceeds the Tcrit values, which are 200 and 250°C for the Mg alloy foam and the Mg alloy/SiCp composite foams, respectively. The Mg alloy/SiCp composite foams exhibit a higher damping capacity than the Mg alloy foam when the temperature is below 200°C. By contrast, the Mg alloy foam exhibits a better damping capacity when the temperature exceeds 250°C. The variation in the damping capacity is attributed to differences in the internal friction sources, such as the characteristics of the matrix material, abundant interfaces, and interfacial slipping caused by SiC particles, as well as to macrodefects in the Mg alloy and its composite foams.

关键词： magnesium alloys foams silicon carbide damping

Improvement on compressive properties of lotus-type porous copper by a nickel coating on pore walls

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Journal of Materials Science & Technology 2020年第2期37卷 114-122页

作者： hao du Chuanyu Cui Housheng Liu Guihong Song Tianying Xiong Division of Surface Engineering of Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China School of Materials Science and Technology Shenyang University of TechnologyShenyang110870China

The aim of this work is to understand the effect of a thin coating on the compressive properties of the porous *** our work,the uniaxial compressive behavior and the energy absorption properties of the lotus-type porous copper deposited with Ni coatings with thickness from 3.9 to 4.8μm on pore walls were *** is found that the Ni coating on pore walls shows a clear enhancement effect on compressive properties of the lotus-type porous copper,in which the specific yield strength and the energy absorption per unit mass at densification strain increase from 5.27 to 7.31 MPa cm3 g-1 and from 11.50 to 18.21 J g-1 with the Ni coating,***,the enhancement appears to be insensitive to the coating *** is considered that the resistance of the interface between the nickel coating and the pore walls to the dislocation slip plays an important role in the improvement on compressive properties of the lotus-type porous copper.

关键词： Lotus-type porous copper Coating Pore walls Compressive properties

Scene image recognition with knowledge transfer for drone navigation

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Journal of Systems Engineering and Electronics 2023年第5期34卷 1309-1318页

作者： du hao WANG Wei WANG Xuerao ZUO Jingqiu WANG Yuanda School of Automation Southeast UniversityNanjing 210096China Autonomous Control Robot Laboratory Jiangsu Zhongke Institute of Applied Research on Intelligent Science and TechnologyChangzhou 213164China Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing University of Information Science and TechnologyNanjing 210044China

In this paper,we study scene image recognition with knowledge transfer for drone *** divide navigation scenes into three macro-classes,namely outdoor special scenes(OSSs),the space from indoors to outdoors or from outdoors to indoors transitional scenes(TSs),and ***,there are difficulties in how to recognize the TSs,to this end,we employ deep convolutional neural network(CNN)based on knowledge transfer,techniques for image augmentation,and fine tuning to solve the ***,there is still a novelty detection prob-lem in the classifier,and we use global navigation satellite sys-tems(GNSS)to solve it in the prediction *** results show our method,with a pre-trained model and fine tun-ing,can achieve 91.3196%top-1 accuracy on Scenes21 dataset,paving the way for drones to learn to understand the scenes around them autonomously.

关键词： scene recognition convolutional neural network knowledge transfer global navigation satellite systems(GNSS)-aided