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Fabrication of triangular Cu_(3)P nanorods on Cu nanosheets as electrocatalyst for boosted electrocatalytic water splitting

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Journal of Central South University 2022年第12期29卷 3870-3883页

作者： DANG Rui XU Xiu-feng XIE Meng-meng Northwest Institute For Nonferrous Metal Research Xi’an 710016China The Faculty of Printing Packaging Engineering and Digital Media TechnologyXi’an University of TechnologyXi’an 710054China

Non-precious electro catalysts with high-efficiency, cheapness and stablility are of great significance to replace noble metal electro catalysts in the hydrogen evolution reaction(HER) and oxygen evolution reaction(OER). In this work, triangular Cu@CuO nanorods on Cu nanosheets were fabricated by a novel in-situ oxidation approach using Cu nanosheets as self-template and conductive nano-substrate in an aqueous solution of NaOH/H2O2, and then by lowtemperature phosphorization treatments. The experimental results show that the phosphating temperature has a significant effect on the morphology, composition and number of active sites of Cu@Cu_(3)P nanorods. The Cu@Cu_(3)P-280 electrode exhibits a good HER catalytic activity of achieving a current density of 10 mA/cm^(2) at 252 mV in acid electrolyte. After catalysis for 14 h, the current density can still reach 72% of the initial value. Moreover, the Cu@Cu_(3)P-280 electrode also shows an excellent OER catalytic activity in basic electrolyte, reaching a current density of 10 mA/cm^(2) at the overpotential value of 200 mV. After catalysis for 12 h, the current density remained more than 93% of the initial value. This work provides a theoretical basis for the directional design and preparation of sustainable, low-cost, bifunctional electrocatalytic materials.

关键词： Cu@Cu_(3)P electrocatalysis oxygen evolution reaction hydrogen evolution reaction

Accelerating the HS-type Richardson Iteration Method with Anderson Mixing

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Acta Mathematica Sinica,English Series 2022年第11期38卷 2069-2089页

作者： Zhi Zhi LI Huai ZHANG Le OU-YANG Key laboratory of Computational Geodynamics University of Chinese Academy of SciencesBeijing 100049P.R.China Guangdong Key laboratory of Intelligent Information Processing Shenzhen Key Laboratory of Media Securityand Guangdong Laboratory of Artificial Intelligence and Digital Economy(SZ)College of Electronics and Information EngineeringShenzhen UniversityShenzhen 518060P.R.China

The Accelerated Hermitian/skew-Hermitian type Richardson(AHSR)iteration methods are presented for solving non-Hermitian positive definite linear systems with three schemes,by using Anderson *** upper bounds of spectral radii of iteration matrices are studied,and then the convergence theories of the AHSR iteration methods are ***,the optimal iteration parameters are provided,which can be computed *** addition,the application to the model convection-diffusion equation is depicted and numerical experiments are conducted to exhibit the effectiveness and confirm the theoretical analysis of the AHSR iteration methods.

关键词： Anderson mixing Hermitian/skew-Hermitian splitting the Richardson iteration convergence analyses optimal parameters the model convection-diffusion equation

Enhancement of the mechanical properties of polylactic acid/basalt fiber composites via in-situ assembling silica nanospheres on the interface

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Journal of Materials Science & Technology 2021年第25期84卷 182-190页

作者： Xianliang Hou Shun Yao Zhen Wang Changqing Fang Tiehu Li School of Materials Science and Engineering Northwestern Polytechnical UniversityXi'an710072China Faculty of Printing Packaging and Digital Media TechnologyXi’an University of TechnologyXi'an710048China

A valid strategy to tailor the properties of polylactic acid for more extensive applications was introducing *** this work,basalt fiber assembled with in-situ SiO_(2) nanoparticles on the surface was successfully prepared via hydrothermal method and it was further treated with coupling agent KH-550 to improve interfacial interaction between polylactic acid(PLA)and basalt fibers(BF).It was demonstrated that the introduction of BFS could increase the crystallization of PLA and resulted in forming trans-crystallization based on TG and DSC *** tensile strength of PLA/BF composites raised from 39 MPa to 62.5 MPa with increasing the fiber loading from 1 wt%to 10 wt%.Furthermore,the interfacial interaction could be effectively improved by assembling SiO_(2)(especially with 250 nm in diameter)on BF surface to build mechanical locking,which could keep the PLA matrix in place during the mechanical deformation with the tensile strength value raised from 62.5 MPa to 74.0 *** is noticeable that the impact and flexural properties were effectively increased with the incorporation of in-situ SiO_(2) *** further KH-550 treatment made a positive impact as *** instance,the impact strength and flexural strength of the sample with SiO_(2) and KH-550 modification were improved to 22.49 k J/m^(2) and 146.83 MPa and it enhanced about 42.16%and 41.04%than those of neat PLA,***,an efficient enhancement of mechanical performance was achieved and this concept of assembling in-situ SiO_(2) on silica-based fiber as a modifier was a novel and simple path to design the interfacial construction and properties of the polymer composites.

关键词： Poly(lactic acid) Basalt fiber Silica nanoparticles In-situ assembled Interface interaction

Quasi-Developable B-Spline Surface Design with Control Rulings

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Journal of Computer Science & Technology 2022年第5期37卷 1221-1238页

作者： Zi-Xuan Hu Peng-Bo Bo Cai-Ming Zhang School of Computer Science and Technology Harbin Institute of TechnologyWeihai 264209China Shandong Co-Innovation Center of Future Intelligent Computing Yantai 264005China Shandong Province Key laboratory of digital media Technology Shandong University of Finance and EconomicsJinan 250061China

We propose a method for generating a ruled B-spline surface fitting to a sequence of pre-defined ruling lines and the generated surface is required to be ***,the terminal ruling lines are treated as hard *** from existing methods that compute a quasi-developable surface from two boundary curves and cannot achieve explicit ruling control,our method controls ruling lines in an intuitive way and serves as an effective tool for computing quasi-developable surfaces from freely-designed *** treat this problem from the point of view of numerical optimization and solve for surfaces meeting the distance error tolerance allowed in *** performance and the efficacy of the proposed method are demonstrated by the experiments on a variety of models including an application of the method for path planning in 5-axis computer numerical control(CNC)flank milling.

关键词： developable surface surface modeling B-spline surface numerical optimization

Improved fuzzy clustering for image segmentation based on a low-rank prior

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Computational Visual media 2021年第4期7卷 513-528页

作者： Xiaofeng Zhang Hua Wang Yan Zhang Xin Gao Gang Wang Caiming Zhang School of Information and Electrical Engineering Ludong UniversityYantai 264025China Shandong Province Key Lab of digital media Technology Shandong University of Finance and EconomicsJinan 250061China

Image segmentation is a basic problem in medical image analysis and useful for disease ***,the complexity of medical images makes image segmentation *** recent decades,fuzzy clustering algorithms have been preferred due to their simplicity and ***,they are sensitive to *** solve this problem,many algorithms using non-local information have been proposed,which perform well but are *** paper proposes an improved fuzzy clustering algorithm utilizing nonlocal self-similarity and a low-rank prior for image ***,cluster centers are initialized based on peak ***,a pixel correlation model between corresponding pixels is constructed,and similar pixel sets are *** improve efficiency and robustness,the proposed algorithm uses a novel objective function combining non-local information and a low-rank *** on synthetic images and medical images illustrate that the algorithm can improve efficiency greatly while achieving satisfactory results.

关键词： image segmentation fuzzy clustering nonlocal information low-rank prior medical images

Asymmetric multilayered MXene-Ag NWs/cellulose nanofiber composite films with antibacterial properties for high-efficiency electromagnetic interference shielding

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Journal of Materials Science & Technology 2022年第34期129卷 181-189页

作者： Fudong Zhang Penggang Ren Zhengzheng Guo Jin Wang Zhengyan Chen Ze Zong Jie Hu Yanling Jin Fang Ren The Faculty of Printing Packaging Engineering and Digital Media TechnologyXi’an University of TechnologyXi’an 710048China School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China

Flexible, lightweight, robust and versatile properties are essential for the next generation of wearable as well as intelligent electromagnetic interference(EMI) shielding materials. In this work, multilayered films containing cellulose nanofiber(CNF) layers, CNF/MXene layers, and CNF/silver nanowires(CNF/Ag NWs)layers were fabricated by an efficient and easy-to-use vacuum filtration method. Compared with a uniformly mixed film, the resultant layered composite films that loaded with a low MXene and AgNWs content exhibit superior mechanical properties with a tensile strength of 137 MPa, a strain at break of 5.7%, excellent EMI shielding effectiveness(EMI SE) of 61.9 d B, and higher EMI SE/t of 20,653 d B cm^(-1).This is attributed to the high-performance CNF substrate, the highly efficient layered structures, and extensive hydrogen-bonding interactions. In particular, a high degree of ohmic loss of multiple interfaces and polarization relaxation of local defects, as well as an abundance of terminal groups, favor the loss of electromagnetic waves(EMW) within the material. In addition, the prepared multifunctional layered composite films also show good antibacterial properties. As a result, the obtained new kind of flexible layered structure EMI shielding composite films with excellent EMI shielding performance, and mechanical properties present promising application prospects in the fields of EMI shielding and protection for aerospace, portable, and wearable flexible electronic devices.

关键词： MXene AgNWs Laminar structure Electromagnetic interference shielding Flexibility

An Improved Frame-Layer Bit Allocation Scheme for H.264/AVC Rate Control

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Journal of Shanghai Jiaotong university(Science) 2009年第2期14卷 143-148页

作者：林贵旭郑世宝朱良家 Institute of Image Communication & Information Processing Department of Electronic EngineeringShanghai Jiaotong University Shanghai Key laboratory of digital media Processing and Transmissions Shanghai Jiaotong University Department of Automatic Control National University of Defense Technology

In this paper,we aim at improving the video quality degradation due to high motions or scene changes. An improved frame-layer bit allocation scheme for H.264/AVC rate control is ***,current frame is pre-encoded in 16×16 modes with a fixed quantization parameter(QP).The frame coding complexity is then measured based on the resulting bits and peak signal-to-ratio(PSNR) in the pre-coding ***,a bit budget is calculated for current frame according to its coding complexity and inter-frame PSNR fluctuation,combined with the buffer *** results show that,in comparison with the H.264 adopted rate control scheme, our method is more efficient to suppress the sharp PSNR drops caused by high motions and scene *** visual quality variations in a sequence are also relieved.

关键词： H.264/AVC rate control bit allocation quality degradation

Saliency detection based on superpixels clustering and stereo disparity

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Applied Mathematics(A Journal of Chinese Universities) 2016年第1期31卷 68-80页

作者： GAO Shan-shan CHI Jing LI Li ZOU Ji-biao ZHANG Cai-ming School of Computer Science and Technology Shandong University of Finance and Economics Jinan 250014 China School of Computer Science and Technology Shandong University Jinan 250100 China. Shandong Provincial Key laboratory of digital media Technology Jinan 250014 China.

Reliable saliency detection can be used to quickly and effectively locate objects in images. In this paper, a novel algorithm for saliency detection based on superpixels clustering and stereo disparity （SDC） is proposed. Firstly, we use an improved superpixels clustering method to decompose the given image. Then, the disparity of each superpixel is computed by a modified stereo correspondence algorithm. Finally, a new measure which combines stereo disparity with color contrast and spatial coherence is defined to evaluate the saliency of each superpixel. From the experiments we can see that regions with high disparity can get higher saliency value, and the saliency maps have the same resolution with the source images, objects in the map have clear boundaries. Due to the use of superpixel and stereo disparity information, the proposed method is computationally efficient and outperforms some state-of-the-art color- based saliency detection methods.

关键词： Saliency detection superpixels stereo disparity spatial coherence.

CAN:Effective Cross Features by Global Attention Mechanism and Neural Network for Ad Click Prediction

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Tsinghua Science and Technology 2022年第1期27卷 186-195页

作者： Wenjie Cai Yufeng Wang Jianhua Ma Qun Jin Nanjing University of Posts and Telecommunications(NJUPT) Nanjing210003China digital media Department in the Faculty of Computer and Information Sciences Hosei UniversityTokyo 163-8001Japan Networked Information Systems laboratory Department of Human Informatics and Cognitive SciencesWaseda UniversityTokyo 163-8001Japan

Online advertising click-through rate(CTR) prediction is aimed at predicting the probability of a user clicking an ad,and it has undergone considerable development in recent *** of the hot topics in this area is the construction of feature interactions to facilitate accurate *** machine provides second-order feature interactions by linearly multiplying hidden feature ***,real-world data present a complex and nonlinear ***,second-order feature interactions are unable to represent cross information *** drawback has been addressed using deep neural networks(DNNs),which enable high-order nonlinear feature ***,DNN-based feature interactions cannot easily optimize deep structures because of the absence of cross information in the original *** this study,we propose an effective CTR prediction algorithm called CAN,which explicitly exploits the benefits of attention mechanisms and DNN *** attention mechanism is used to provide rich and expressive low-order feature interactions and facilitate the optimization of DNN-based predictors that implicitly incorporate high-order nonlinear feature *** experiments using two real datasets demonstrate that our proposed CAN model performs better than other cross feature-and DNN-based predictors.

关键词： click-through rate prediction global attention mechanism feature interaction neural network