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Dark Solitary-Wave Solutions in Bulk linear Media with Group Velocity Dispersion

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Chinese Physics Letters 1995年第7期12卷 396-399页

作者： li zhonghao ZHOU Guosheng Department of Electronics and Information Science Shanxi UniversityTaiyuan 030006

A dark envelope solitary-wave solution in bulk dispersive linear media is obtained from the (3+1)-dimensional time-space coupled linear wave equation by taking account of the interplay between physical effects of transverse confinement and group velocity dispersion (GVD) effect under certain appropriate *** characteristics of the solution are discussed in both normal and anomalous GVD regions.

关键词： conditions. Dispersion wave

预热处理对GH4698合金微观组织及性能的影响

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精密成形工程 2025年第2期17卷 141-149页

作者：江权安黄亮李中豪班宜杰高首磊华中科技大学材料科学与工程学院材料成形与模具技术全国重点实验室武汉430074 大冶特殊钢有限公司湖北黄石435001

目的针对锻后GH4698合金组织分布不均匀造成综合力学性能难以平衡的问题,提出通过预热处理来对合金的组织和性能进行优化,并深入探究不同预热处理制度对GH4698合金组织演化和性能的影响。方法在标准四段式热处理之前增加预热处理实验(11... 详细信息

目的针对锻后GH4698合金组织分布不均匀造成综合力学性能难以平衡的问题,提出通过预热处理来对合金的组织和性能进行优化,并深入探究不同预热处理制度对GH4698合金组织演化和性能的影响。方法在标准四段式热处理之前增加预热处理实验(1173~1273 K,2~8 h),观察不同预热处理条件下GH4698合金析出相尺寸和形貌,采用拉伸实验机与维氏硬度计获得不同预热处理条件下GH4698合金的力学性能,结合拉伸试样断口形貌,分析GH4698合金的断裂机制。结果当预热处理温度为1223 K时,合金内部大γ′相分布均匀,且小γ′相析出量达到峰值,尺寸为15~25 nm;在所研究的预热处理温度和时间范围内,GH4698合金的屈服强度、抗拉强度、延伸率和维氏硬度均呈现先上升后下降的趋势。GH4698合金的断裂形式为沿晶断裂+韧窝的混合断裂模式。结论预热处理温度和时间对γ′相的形貌、尺寸及数量有着显著的影响,相较于未经预热处理的试样,最优的预热处理参数(1223 K/4 h)下的合金屈服强度、抗拉强度、延伸率和维氏硬度分别提升了5.06%、5.48%、3.29%和10.30%。

关键词： GH4698 预热处理微观组织力学性能

Deep eutectic solvent strategy enables an octahedral Ni–Co precursor for creating high-performance NiCo_(2)O_(4) catalyst toward oxygen evolution reaction

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Green Energy & Environment 2022年第6期7卷 1217-1227页

作者： Chenyun Zhang Bingwei Xin Tingting Chen Hao Ying zhonghao li Jingcheng Hao Key Laboratory of Colloid and Interface Chemistry Ministry of EducationShandong UniversityJinan250100China College of Chemistry and Chemical Engineering Dezhou UniversityDezhou253023China

Deep eutectic solvents(DESs)have gained much attention in the fabrication of advanced nanoelectrocatalysts due to their amazing template ***,their stabilizing function for easily hydrolyzed inorganic nanomaterials is rarely ***,a DES-mediated strategy was reported to synthesize octahedral Ni–Co precursor(NiCo–NH_(3) complex),which could be directly transformed into NiCo_(2)O_(4) nanooctahedrons after thermal *** NiCo–NH_(3) precursor in octahedral shape was achieved with the DES-mediated crystallization in the choline chloride(ChCl)/*** ChCl/glycerol DES not only tailored the morphology of the as-prepared precursor by template effect but also inhibited its hydrolysis,ensuring the successful fabrication of octahedral NiCo–NH_(3) complex precursor with high *** NiCo–NH_(3) complex precursor was converted to well-defined NiCo_(2)O_(4) nanooctahedrons,where the calcination temperature and time were explored in *** revealed that DES could participate in the conversion process to control the morphology of calcination *** resultant NiCo_(2)O_(4) nanooctahedrons demonstrated excellent electroactivity and remarkable durability for oxygen evolution reaction(OER).The present strategy not only offers an efficient OER electrocatalyst but also enriches the approaches of DESs in designing advanced nanocatalysts.

关键词： Deep eutectic solvents Choline chloride Glycerol Oxygen evolution reaction

A HEVC Video Steganalysis Algorithm Based on PU Partition Modes

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Computers, Materials & Continua 2019年第5期59卷 563-574页

作者： zhonghao li Laijing Meng Shutong Xu Zhaohong li Yunqing Shi Yuanchang liang School of Electronic and Information Engineering Beijing JiaoTong UniversityBeijing100044China Guangdong Provincial Key Laboratory of Information Security Technology Guangzhou510000China Department of Electrical and Computer Engineering New Jersey Institute of TechnologyNewark07102USA

Steganalysis is a technique used for detecting the existence of secret information embedded into cover media such as images and ***,with the higher speed of the Internet,videos have become a kind of main methods for transferring *** latest video coding standard High Efficiency Video Coding(HEVC)shows better coding performance compared with the H.264/AVC standard published in the previous ***,since the HEVC was published,HEVC videos have been widely used as carriers of hidden *** this paper,a steganalysis algorithm is proposed to detect the latest HEVC video steganography method which is based on the modification of Prediction Units(PU)partition *** detect the embedded data,All the PU partition modes are extracted from P pictures,and the probability of each PU partition mode in cover videos and stego videos is adopted as the classification ***,feature optimization is applied,that the 25-dimensional steganalysis feature has been reduced to the 3-dimensional *** the Support Vector Machine(SVM)is used to identify stego *** is demonstrated in experimental results that the proposed steganalysis algorithm can effectively detect the stego videos,and much higher classification accuracy has been achieved compared with state-of-the-art work.

关键词： Video steganalysis PU partition modes data hiding HEVC videos

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基于步态特征的性别识别方法研究

中国民航飞行学院学报 2025年第1期36卷 59-64页

作者：李忠浩罗文田陈乾覃华懋中国民用航空飞行学院四川广汉618307

本文基于步态特征设计了一套人物性别识别模型。以能量图的形式作为该模型的输入,模型采用串联式的网络结构并利用Softmax函数进行最终的人物性别识别。然后将CASIA-B数据库中的步态轮廓图裁剪合成能量图输入模型测试性别识别得到91%以... 详细信息

本文基于步态特征设计了一套人物性别识别模型。以能量图的形式作为该模型的输入,模型采用串联式的网络结构并利用Softmax函数进行最终的人物性别识别。然后将CASIA-B数据库中的步态轮廓图裁剪合成能量图输入模型测试性别识别得到91%以上的整体识别准确率。最后设计实验对比本文模型和VGG、ResNet识别模型,实验结果表明该模型针对人物性别识别有着更好的泛化性能和效率。

关键词：神经网络步态特征能量图性别识别

Measurement and model of density,viscosity,and hydrogen sulfide solubility in ferric chloride/trioctylmethylammonium chloride ionic liquid

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Chinese Journal of Chemical Engineering 2023年第7期59卷 210-221页

作者： zhonghao li Yuanyuan Yang Huanong Cheng Yun Teng Chao li Kangkang li Zhou Feng Hongwei Jin Xinshun Tan Shiqing Zheng College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China

The density and viscosity of ferric chloride/trioctylmethylammonium chloride ionic liquid(rFeCl_(3)/[A336]Cl)with different molar ratios(r=0.1-0.8)of FeCl_(3) to[A336]Cl were measured at temperatures from 313.15 to 358.15 K and atmospheric *** density and viscosity data were fitted by the relevant temperature variation equations,*** variation of density and viscosity with temperature and r was *** solubility of rFeCl_(3)/[A336]Cl to H_2S was measured at temperatures from 318.15 to 348.15 K and pressures from 0 to 150 *** effects of temperature,pressure,and r on the solubility of H_(2)S were *** reaction equilibrium thermodynamic model(RETM)was used to fit the H_(2)S solubility data,and the average relative error was less than 1.3%,indicating that the model can relate the solubility data *** Henry's constant and chemical reaction equilibrium constant were obtained by the RETM *** relationships of Henry's constant and chemical reaction equilibrium constant with temperature and r were analyzed.

关键词： Ionic liquids Hydrogen sulfide Solubility Henry's constant Chemical reaction equilibrium constant Model

A Spark Scheduling Strategy for Heterogeneous Cluster

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Computers, Materials & Continua 2018年第6期55卷 405-417页

作者： Xuewen Zhang zhonghao li Gongshen liu Jiajun Xu Tiankai Xie Jan Pan Nees School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai200240P.R.C. Eberly College of Science Pennsylvania State UniversityOld MainState CollegePA 16801U.S.A.

As a main distributed computing system,Spark has been used to solve problems with more and more complex ***,the native scheduling strategy of Spark assumes it works on a homogenized cluster,which is not so effective when it comes to heterogeneous *** aim of this study is looking for a more effective strategy to schedule tasks and adding it to the source code of *** investigating Spark scheduling principles and mechanisms,we developed a stratifying algorithm and a node scheduling algorithm is proposed in this paper to optimize the native scheduling strategy of *** this new strategy,the static level of nodes is calculated,the dynamic factors such as the length of running tasks,and CPU usage of work nodes are considered *** through a series of comparative experiments in alienation cluster,the new strategy costs less running time and lower CPU usage rate than the original Spark strategy,which verifies that the new schedule strategy is more effective one.

关键词： Spark optimize scheduling stratifying algorithm performance optimization

A Novel Method for Determining the Void Fraction in Gas-liquid Multi-Phase Systems Using a Dynamic Conductivity Probe

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Fluid Dynamics & Materials Processing 2024年第6期20卷 1233-1249页

作者： Xiaochu Luo Xiaobing Qi Zhao Luo zhonghao li Ruiquan liao Xingkai Zhang Hubei Key Laboratory of Oil and Gas Drilling and Production Engineering Yangtze UniversityWuhan434000China Oil and Gas Engineering Research Institute PetroChina Tarim Oilfield CompanyKorla84100China Xinjiang Kunlun Engineering Consulting Co. Ltd.Karamay834000China Petrochina Dagang Oilfield Company Production Technology Research Institute Tianjin300000China

Conventional conductivity methods for measuring the void fraction in gas-liquid multiphase systems are typically affected by accuracy problems due to the presence of fluid flow and *** study presents a novel approach for determining the void fraction based on a reciprocating dynamic conductivity probe used to measure the liquid film thickness under forced annular-flow *** measurement system comprises a cyclone,a conductivity probe,a probe reciprocating device,and a data acquisition and processing *** method ensures that the flow pattern is adjusted to a forced annular flow,thereby minimizing the influence of complex and variable gas-liquid flow patterns on the measurement results;Moreover,it determines the liquid film thickness solely according to circuit connectivity rather than specific conductivity values,thereby mitigating the impact of *** reliability of the measurement system is demonstrated through laboratory *** experimental results indicate that,in a range of gas phase superficial velocities 5–20 m/s and liquid phase superficial velocities 0.079–0.48 m/s,the maximum measurement deviation for the void fraction is 4.23%.

关键词： Forced annular flow dynamic conductivity probe void fraction gas-liquid flow liquid film thickness

Absorption characteristics,model,and molecular mechanism of hydrogen sulfide in morpholine acetate aqueous solution

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Chinese Journal of Chemical Engineering 2024年第2期66卷 125-135页

作者： Hongwei Jin Yun Teng Kangkang li Zhou Feng zhonghao li Shiqi Qu Hongzhi Xia Huanong Cheng Yugang li Xinshun Tan Shiqing Zheng College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China

The solubility of H_(2)S was measured in solutions of N-butyl-N-methylmorpholine acetate([Bmmorp][Ac])containing 20%-40%(mass)water at experimental temperatures ranged from 298.15 to 328.15 K and pressures up to 320 k *** total solubility of H_(2)S increased with higher temperatures,lower pressures,and reduced water *** reaction equilibrium thermodynamic model was used to correlate the solubility *** results indicate that the chemical reaction equilibrium constant decrease with increasing water content and temperature,whereas Henry constant increase with increasing water content and *** with other ionic liquids,H_(2)S exhibits a higher physical absorption enthalpy and a lower chemical absorption enthalpy in[Bmmorp][Ac]aqueous *** suggests that[Bmmorp][Ac]has a strong physical affinity for H_(2)S and low energy requirement for *** chemical methods were used to investigate the molecular mechanism of H_(2)S absorption in ionic *** interaction energy analysis revealed that the binding of H_(2)S with the ionic liquid in a1:2 ratio is more *** analyses by the methods of the interaction region indicator and the atoms in molecules were conducted to the interactions between H_(2)S and the ionic liquid.

关键词： Ionic liquid Hydrogen sulfide Model Solubility Molecular mechanism