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两步烧结氧化钪掺杂氧化锌非线性电阻的制备及性能研究

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电瓷避雷器 2024年第1期 46-50页

作者：石梦阳姜明徐东安徽工业大学材料科学与工程学院安徽马鞍山243002

采用两步烧结法制备稀土掺杂的氧化锌基非线性电阻,通过对其显微组织、相结构和电性能的分析,探讨不同含量的Sc_(2)O_(3)对氧化锌非线性电阻的影响。结果表明,两部烧结制备出的样品的致密度均高于97%。当Sc_(2)O_(3)掺杂量掺杂浓度为0.1... 详细信息

采用两步烧结法制备稀土掺杂的氧化锌基非线性电阻,通过对其显微组织、相结构和电性能的分析,探讨不同含量的Sc_(2)O_(3)对氧化锌非线性电阻的影响。结果表明,两部烧结制备出的样品的致密度均高于97%。当Sc_(2)O_(3)掺杂量掺杂浓度为0.1%时ZnO非线性电阻的综合电性能最好,电位梯度为958 V/mm,非线性系数为61.2。因此,通过两步法烧结掺杂Sc_(2)O_(3)的ZnO非线性电阻可以获得均匀的显微结构和优异的电学性能。

关键词：非线性电阻 ZnO Sc_(2)O_(3) 两步烧结电性能

Helium extraction from natural gas using DD3R zeolite membranes

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Chinese Journal of Chemical Engineering 2022年第9期35卷 122-129页

作者： Ping Zhang Chao Gong Tao Zhou Peng Du Jieyu Song mengyang shi Xuerui Wang Xuehong Gu State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringJiangsu National Synergetic Innovation Center for Advanced MaterialsNanjing Tech UniversityNanjing 211816China

Helium(He)is commercially produced from natural gas by low-temperature *** process is energy extensive because of the extremely low He concentration(<0.3%)and the operation at cryogenic *** we demonstrated DD3R zeolite membrane was efficient to extract He from natural gas at atmosphere *** membrane performance was evaluated in terms of temperature,pressure and molar *** overall membrane performance was dominated by the diffusivity *** single He permeance and ideal He/CH_(4) selectivity were 5.8×10^(-9)mol·m^(-2)·s^(-1)·Pa^(-1)and 79 under a feed pressure of 1.3 *** though He concentration was as low as 0.22%,the He permeance and He/CH_(4) mixture selectivity were 3.0×10^(-9)mol·m^(-2)·s^(-1)·Pa^(-1)and 44 at 0.7 *** the longterm operation(~130 h)the membrane performance was stable even the feed mixture containing3.6%ethane as *** results approved the feasibility of DD3R zeolite membranes for He extraction from natural gas.

关键词： He extraction Zeolite Membranes He/CH_(4)separation Natural gas

Anti-aging performance improvement and enhanced combustion efficiency of boron via the coating of PDA

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Defence Technology（防务技术） 2024年第3期33卷 399-410页

作者： Shuai Ma Qinghai Shu mengyang Zhang Hongyu Huang Yansong shi Xijuan Lv Shuai Zhao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China Key Lab of Advanced Optoelectronic Quantum Architecture and Measurement(MOE) Beijing Key Lab of Nanophotonics&Ultrafine Optoelectronic SystemsSchool of PhysicsBeijing Institute of TechnologyBeijing100081China Tangshan Research Institute of Beijing Institute of Technology Tangshan063000HebeiChina

Boron is an ambitious fuel in energetic materials since its high heat release values,but its application is prohibited by low combustion efficiency and oxidization during *** polydopamine(PDA)was introduced into boron particles,investigating the impact of PDA content on the energetic behavior of *** results indicated that the PDA coating formed a fishing net structure on the surface of boron *** heat release results showed that the combustion calorific value of B@PDA was higher than that of the raw ***,the actual combustion heat of boron powder in B@10%PDA increased by 38.08%.Meanwhile,the DSC peak temperature decreased by 100.65℃under similar oxidation rate compared to raw ***,the B@PDA@AP and B@AP composites were prepared,and their combustion properties were *** was demonstrated that B@10%PDA@AP exhibited superior performance in terms of peak pressure and burning time,*** peak pressure is 12.43 kPa more than B@AP and burning time is 2.22 times higher than B@***,the coating of PDA effectively inhibits the oxidization of boron during storage and enhances the energetic behavior of boron and corresponding composites.

关键词： Boron particles Polydopamine Anti-aging performance improvement Heat release

Multifunctional solar-blind ultraviolet photodetectors based on p-PCDTBT/n-Ga_(2)O_(3)heterojunction with high photoresponse

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InfoMat 2024年第2期6卷 118-130页

作者： Yifei Wang Zhenhua Lin Jingli Ma Yongyi Wu Haidong Yuan Dongsheng Cui mengyang Kang XingGuo Jie Su Jinshui Miao Zhifeng shi Tao Li Jincheng Zhang Yue Hao Jingjing Chang State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology School of MicroelectronicsXidian UniversityXi'anthe People's Republic of China School of Physics and Microelectronics Key Laboratory of Material PhysicsMinistry of EducationZhengzhou UniversityZhengzhouthe People's Republic of China Center for Spintronics and Quantum Systems State Key Laboratory for Mechanical Behavior of MaterialsDepartment of Materials Science and EngineeringXi'an Jiaotong UniversityXi'anthe People's Republic of China Advanced Interdisciplinary Research Center for Flexible Electronics Xidian UniversityXi'anthe People's Republic of China State Key Laboratory of Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghaithe People's Republic of China

Solar-blind ultraviolet(UV)photodetectors based on p-organic/n-Ga_(2)O_(3) hybrid heterojunctions have attracted extensive attention ***,the multifunctional solar-blind photodetector based on p-type poly[N-90-heptadecanyl-2,7-carbazole-alt-5,5-(40,70-di-2-thienyl-20,10,30-benzothiadiazole)](PCDTBT)/n-type amorphous Ga_(2)O_(3)(a-Ga_(2)O_(3))is fabricated and investigated,which can work in the phototransistor mode coupling with self-powered *** the introduction of PCDTBT,the dark current of such the a-Ga_(2)O_(3)-based photodetector is decreased to 0.48 ***,the photoresponse parameters of the a-Ga_(2)O_(3)-based photodetector in the phototransistor mode to solar-blind UV light are further increased,that is,responsivity(R),photo-detectivity(D*),and external quantum efficiency(EQE)enhanced to 187 A W^(-1),1.3×10^(16) Jones and 9.1×10^(4)% under the weak light intensity of 11μW cm^(-2),*** to the formation of the built-in field in the p-PCDTBT/n-Ga_(2)O_(3) type-Ⅱ heterojunction,the PCDTBT/Ga_(2)O_(3) multifunctional photodetector shows self-powered *** responsivity of p-PCDTBT/n-Ga_(2)O_(3) multifunctional photodetector is 57.5 mA W^(-1) at zero *** multifunctional p-n hybrid heterojunction-based photodetectors set the stage for realizing high-performance amorphous Ga_(2)O_(3) heterojunction-based photodetectors.

关键词： amorphous Ga_(2)O_(3) heterojunction multifunctional PCDTBT solar-blind photodetectors

基于有向线段误匹配剔除的煤矿巷道复杂场景图像拼接方法

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煤炭科学技术 2022年第9期50卷 179-191页

作者：程健闫鹏鹏郁华森史梦阳肖洪飞煤炭科学研究总院矿山大数据研究院北京100013 煤炭资源高效开采与洁净利用国家重点实验室北京100013 中国矿业大学信息与控制工程学院江苏徐州221116 首都医科大学生物医学工程学院北京100069

为解决煤矿巷道复杂场景图像特征点误匹配较多和图像拼接过程中易出现的投影失真问题,提出了一种基于有向线段误匹配剔除的煤矿巷道图像拼接方法。首先,使用SIFT(Scale Invariant Feature Transform)算法进行图像特征提取与匹配,得到粗... 详细信息

为解决煤矿巷道复杂场景图像特征点误匹配较多和图像拼接过程中易出现的投影失真问题,提出了一种基于有向线段误匹配剔除的煤矿巷道图像拼接方法。首先,使用SIFT(Scale Invariant Feature Transform)算法进行图像特征提取与匹配,得到粗匹配点对;然后构造相邻图像粗匹配点对有向线段模型,利用线段的方向和长度属性对误匹配点对进行一次剔除;接下来建立各自图像之内的特征点有向线段模型及其方向标签,再对相邻图像对应有向线段进行方向匹配,并通过概率统计模型对误匹配点对进行二次剔除,得到最终的精匹配点对;最后,建立图像网格模型,利用AANAP(Adaptive As-Natural-As-Possible)算法对齐拼接图像,并使用加权平均法融合图像,完成图像拼接。在煤矿巷道图像和4组公共数据集上进行特征匹配和图像拼接试验,该算法较RANSAC(RANdom SAmple Consensus)算法实时性更好,匹配点精度更高;并且对应的煤矿巷道图像拼接的配准精度更高,得到的全景拼接图观感自然度更好。试验结果表明,该算法对于煤矿巷道复杂场景具有较高拼接精度和较好的拼接效果,同时具有较好的鲁棒性和有效性。

关键词：误匹配剔除有向线段 AANAP 图像拼接煤矿巷道

Adaptive Space Expansion for Fast Motion Planning

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1499-1514页

作者： Shenglei shi Jiankui Chen State Key Laboratory of Digital Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The sampling process is very inefficient for sam-pling-based motion planning algorithms that excess random sam-ples are generated in the planning *** this paper,we pro-pose an adaptive space expansion(ASE)approach which belongs to the informed sampling category to improve the sampling effi-ciency for quickly finding a feasible *** ASE method enlarges the search space gradually and restrains the sampling process in a sequence of small hyper-ellipsoid ring subsets to avoid exploring the unnecessary ***,for a con-structed small hyper-ellipsoid ring subset,if the algorithm cannot find a feasible path in it,then the subset is ***,the ASE method successively does space exploring and space expan-sion until the final path has been ***,we present a particular construction method of the hyper-ellipsoid ring that uniform random samples can be directly generated in *** last,we present a feasible motion planner BiASE and an asymptoti-cally optimal motion planner BiASE*using the bidirectional exploring method and the ASE *** demon-strate that the computation speed is much faster than that of the state-of-the-art *** source codes are available at https://***/shshlei/ompl.

关键词： Adaptive space expansion(ASE) hyper-ellipsoid ring informed sampling motion planning.

Quantization and Event-Triggered Policy Design for Encrypted Networked Control

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 946-955页

作者： Yongxia shi Ehsan Nekouei the Department of Electrical Engineering City University of Hong KongHong KongChina

This paper proposes a novel event-driven encrypted control framework for linear networked control systems(NCSs),which relies on two modified uniform quantization policies,the Paillier cryptosystem,and an event-triggered *** to the fact that only integers can work in the Pailler cryptosystem,both the real-valued control gain and system state need to be first quantized before *** is dramatically different from the existing quantized control methods,where only the quantization of a single value,e.g.,the control input or the system state,is *** handle this issue,static and dynamic quantization policies are presented,which achieve the desired integer conversions and guarantee asymptotic convergence of the quantized system state to the ***,the quantized system state is encrypted and sent to the controller when the triggering condition,specified by a state-based event-triggered strategy,is *** doing so,not only the security and confidentiality of data transmitted over the communication network are protected,but also the ciphertext expansion phenomenon can be ***,by tactfully designing the quantization sensitivities and triggering error,the proposed event-driven encrypted control framework ensures the asymptotic stability of the overall closedloop ***,a simulation example of the secure motion control for an inverted pendulum cart system is presented to evaluate the effectiveness of the theoretical results.

关键词： Cyber-security encrypted control event-triggered control(ETC) networked control systems(NCSs) semi-homomorphic encryption

An uncertainty investigation for liner impedance eduction methods

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Chinese Journal of Aeronautics 2024年第3期37卷 49-59页

作者： Weihao shi Xiaodong JING School of Energy and Power Engineering Beihang UniversityBeijing 100191China

Impedance eduction methods have been developed for decades to meet the increasing need for high-quality impedance data in the design and optimization of acoustic *** this end,it is important to fully investigate the uncertainty problem,to which only limited attention has been devoted so *** paper considers the possibility of acoustically-induced structural vibration as a nonnegligible uncertainty or error source in impedance eduction *** the frequency moves away from the resonant frequency,with the increase in the value of cavity reactance,the acoustic particle velocity inside liner orifices possibly decreases to the extent comparable to the vibration velocity of liner facing ***,the acoustically-induced vibration,although generally being weak except at the inherent structural frequencies,may considerably affect the impedance eduction results near the anti-resonant frequency where the liner has poor *** demonstrate the effect of structural vibration,the vibration velocity of liner facing sheet is estimated from the experimentally educed admittance of the liner samples whose orifices are sealed with ***,a three-dimensional numerical model is set up,in which normal particle velocity is introduced over the solid portion of liner facing sheet to imitate structural vibration,rather than directly solving the acoustic-structural coupling *** shown by the results,the vibration of liner facing sheet,whose velocity is as small as estimated by the experiment,can result in anomalous deviation of the educed impedance from the impedance model near the anti-resonant *** trend that the anomalous deviation varies with frequency is numerically captured.

关键词： Impedance eduction Uncertainty analysis Acoustically-induced structural vibration Anti-resonant frequency Perforated liner

No Reference Image Sharpness Assessment Based on Global Color Difference Variation

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Chinese Journal of Electronics 2024年第1期33卷 293-302页

作者： Chenyang shi Yandan LIN School of Artificial Intelligence Anhui Polytechnic University School of Mechanical Engineering Anhui Polytechnic University Department of Light Sources and Illuminating Engineering Fudan University Academy for Engineering & Technology Fudan University

Image quality assessment(IQA) model is designed to measure the image quality in consistent with subjective ratings by computational models. In this research, a valid no reference IQA(NR-IQA) model for color image sharpness assessment is proposed based on local color difference map in a color space. In the proposed model, the absolute color difference variation and relative color difference variation are combined to evaluate sharpness in YIQ color space(a color coordinate system for the development of the United States color television system). The difference between sharpest and blurriest spot of an image is represented by the absolute color difference variation, and relative color difference variation expresses the variation in the image content. Extensive experiments are performed on five publicly available benchmark synthetic blur databases and two real blur databases, and the results prove that the proposed model work better than the other state-of-the-art and latest NR-IQA models for the prediction accuracy on blurry images. Besides, the model maintains the lowest computational complexity.

关键词： Image quality TV Image color analysis Databases Computational modeling Color Predictive models

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