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基于GRU神经网络的恒温晶振频率漂移预测

电子器件 2024年第2期47卷 502-508页

作者：王彬晏学成张海利刘岳巍石家庄铁道大学电气与电子工程学院河北石家庄050043 河北远东通信系统工程有限公司河北石家庄050200

恒温晶振作为新时代5G通信系统的重要器件,其频率稳定性相当重要,准确预测恒温晶振频率漂移可以提高系统工作状态的安全性与可靠性。为进一步提高频率漂移预测精度,满足5G通信系统需求,提出了一种基于门控循环单元(GRU)神经网络的晶振... 详细信息

恒温晶振作为新时代5G通信系统的重要器件,其频率稳定性相当重要,准确预测恒温晶振频率漂移可以提高系统工作状态的安全性与可靠性。为进一步提高频率漂移预测精度,满足5G通信系统需求,提出了一种基于门控循环单元(GRU)神经网络的晶振频率预测模型。该模型同时考虑温度、老化两种因素,并利用神经网络具有出色的自适应性与非线性泛化能力,学习恒温晶振频率漂移变化规律。最后以14 d实测数据为例进行研究分析,并与循环神经网络、长短时记忆神经网络做对比实验,以均方根误差、平均绝对误差、算法运行时间作为评价指标,结果表明GRU网络具有更高的预测精度、更快的运算速度。

关键词：恒温晶振频率漂移预测温度老化 GRU神经网络

Tuning oxygen vacancies in two-dimensional iron-cobalt oxide nanosheets through hydrogenation for enhanced oxygen evolution activity

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Nano Research 2018年第6期11卷 3509-3518页

作者： Linzhou Zhuang Yi Jia Tianwei He Aijun Du xuecheng yan Lei Ge Zhonghua Zhu Xiangdong Yao School of Chemical Engineering The University of Queensland Brisbane 4072 Australia School of Environment and Science and Queensland Micro- and Nanotechnology Centre Griffith University Nathan Campus Brisbane 4111 Australia School of Chemistry Physics and Mechanical Engineering Queensland University of Technology Gardens Point Campus Brisbane 4001 Australia

The oxygen evolution reaction （OER） represents the rate-determining step of electrocatalytic water splitting into hydrogen and oxygen. Creating oxygen vacancies and adjusting their density has proven to be an effective strategy to design high-performance OER catalysts. Herein, a hydrogenation method is applied to treat a two-dimensional （2D） iron-cobalt oxide （Fe1Co1Ox-origin）, with the purpose of tuning its oxygen vacancy density. Notably, compared with Fe1Co1Ox-origin, the iron-cobalt oxide hydrogenated at 200℃ and 2.0 MPa optimized conditions exhibits a markedly improved OER activity in 1.0 M KOH （with an overpotential 17 of 225 mV at a current density of 10 ***^-2） and a rapid reaction kinetics （with a Tafel slope of 36.0 mV·dec^-1）. Moreover, the OER mass activity of the hydrogenated oxide is 1.9 times that of Fe1Co1Ox-origin at an overpotential of 350 mV. The experimental results, combined with density functional theory （DFT） calculations, reveal that the optimal control of oxygen vacancies in 2D Fe1Co1Ox via hydrogenation can improve the electronic conductivity and promote OH- adsorption onto nearby low-coordinated Co^3＋ sites, resulting in a significantly enhanced OER activity.

关键词： hydrogenation tuning oxygen vacancy oxygen evolution reaction

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高气液比水平井临界携液流量预测新模型

断块油气田 2024年第5期31卷 843-850页

作者：黄全华黄智程杨亚涛刘书炳王定峰颜学成刘磊西南石油大学四川成都610500 中国石油长庆油田长北作业分公司陕西西安710018

明确气井积液机理和携液规律对于掌握井下流体的流动状态至关重要。目前现场应用的临界携液流量模型较多,但是不同模型计算结果差异较大,Turner等模型计算的长北区块气井携液流量偏大,不利于指导生产。通过开展水平井流动模拟正交实验,... 详细信息

明确气井积液机理和携液规律对于掌握井下流体的流动状态至关重要。目前现场应用的临界携液流量模型较多,但是不同模型计算结果差异较大,Turner等模型计算的长北区块气井携液流量偏大,不利于指导生产。通过开展水平井流动模拟正交实验,捕捉典型流态,发现管斜角在45°~60°出现过渡流,通过编制流态识别程序进一步确定管斜角为46°时开始出现过渡流,此时携液最困难。基于液滴理论,引入井斜修正系数,建立了新的临界携液流量模型,新模型在长北区块气井中具有良好的适用性。新模型敏感性分析结果表明,由强到弱影响气井携液能力的因素依次为油管内径、井底流压、井斜角、井底温度。绘制的临界携液流量图版为后期开展停喷井治理措施的时机提供了依据。

关键词：高气液比水平井积液机理液滴模型流态实验临界携液流量

Network Intrusion Traffic Detection Based on Feature Extraction

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Computers, Materials & Continua 2024年第1期78卷 473-492页

作者： xuecheng Yu yan Huang Yu Zhang Mingyang Song Zhenhong Jia College of Information Science and Engineering Xinjiang UniversityUrumqi830046China Network Department China Mobile Communications Group Xinjiang CoLtd.UrumqiUrumqi830011China Xinjiang Signal Detection and Processing Key Laboratory Xinjiang UniversityUrumqi830000China

With the increasing dimensionality of network traffic,extracting effective traffic features and improving the identification accuracy of different intrusion traffic have become critical in intrusion detection systems(IDS).However,both unsupervised and semisupervised anomalous traffic detection methods suffer from the drawback of ignoring potential correlations between features,resulting in an analysis that is not an optimal ***,in order to extract more representative traffic features as well as to improve the accuracy of traffic identification,this paper proposes a feature dimensionality reduction method combining principal component analysis and Hotelling’s T^(2) and a multilayer convolutional bidirectional long short-term memory(MSC_BiLSTM)classifier model for network traffic intrusion *** method reduces the parameters and redundancy of the model by feature extraction and extracts the dependent features between the data by a bidirectional long short-term memory(BiLSTM)network,which fully considers the influence between the before and after *** network traffic is first characteristically downscaled by principal component analysis(PCA),and then the downscaled principal components are used as input to Hotelling’s T^(2) to compare the differences between *** datasets with outliers,Hotelling’s T^(2) can help identify the groups where the outliers are located and quantitatively measure the extent of the ***,a multilayer convolutional neural network and a BiLSTM network are used to extract the spatial and temporal features of network traffic *** empirical consequences exhibit that the suggested approach in this manuscript attains superior outcomes in precision,recall and F1-score juxtaposed with the prevailing *** results show that the intrusion detection accuracy,precision,and F1-score of the proposed MSC_BiLSTM model for the CIC-IDS 2017 dataset are 98.71%,95.97%,and 90.22%.

关键词： Network intrusion traffic detection PCA Hotelling’s T^(2) BiLSTM

Platinum stabilized by defective activated carbon with excellent oxygen reduction performance in alkaline media

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Chinese Journal of Catalysis 2017年第6期38卷 1011-1020页

作者： xuecheng yan Yi Jia Longzhou Zhang Xiangdong Yao School of Natural Sciences and Queensland Micro‐ and Nanotechnology Centre Griffith University Nathan Campus QLD 4111 Australia

The exploration of highly active and durable cathodic oxygen reduction reaction(ORR)catalysts with economical production cost is still the bottleneck to realize the large‐scale commercialization of fuel cells and metal‐air *** that carbon support is crucial to the electrocatalysts,and Pt is the best‐known ORR catalyst so far,in this work,we employed a simple impregnation method for synthesizing a kind of defective activated carbon(D‐AC)supported low Pt content electrocatalysts for the *** reduction conditions of the Pt‐containing precursor were firstly optimized,and the influence of the Pt loading amount on the ORR was investigated as *** results show that the obtained D‐AC@5.0%Pt sample(contains5wt%Pt)has surpassed the commercial Pt/C with20wt%Pt for the ORR in an alkaline *** the meantime,it is more stable than the commercial Pt/*** outstanding ORR performance of the D‐AC@5.0%Pt confirms that both the unique defects in the D‐AC and the introduced Pt particles are indispensable to the ***,m the ORR activity of the synthesized catalysts is superior to most of the reported counterparts,but with much easier preparation methods and lower production cost,making them more advantageous in practical fuel cell applications.

关键词： Activated carbon Defect Platinum Oxygen reduction reaction Fuel cell

Controllable synthesis of Fe–N4 species for acidic oxygen reduction

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Carbon Energy 2020年第3期2卷 452-460页

作者： xuecheng yan Yi Jia Kang Wang Zhao Jin Chung-Li Dong Yu-Cheng Huang Jun Chen Xiangdong Yao Queensland Micro-and Nanotechnology Centre Griffith UniversityNathan CampusQueenslandAustralia Department of Chemistry University of Science and Technology BeijingBeijingChina Laboratory of Advanced Power Sources Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchunChina Department of Physics Tamkang UniversityNew Taipei CityTaiwan Intelligent Polymer Research Institute ARC Centre of Excellence for Electromaterials ScienceAIIM FacilityUniversity of WollongongInnovation CampusWollongongNew South WalesAustralia

Controllable design and synthesis of catalysts with the target active sites are extremely important for their applications such as for the oxygen reduction reaction(ORR)in fuel ***,the controllably synthesizing electrocatalysts with a single type of active site still remains a grand *** this study,we developed a facile and scalable method for fabricating highly efficient ORR electrocatalysts with sole atomic Fe-N4 species as the active ***,the use of cost-effective highly porous carbon as the support not only could avoid the aggregation of the atomic Fe species but also a feasible approach to reduce the catalyst *** obtained atomic Fe-N4 in activated carbon(aFe@AC)shows excellent ORR *** half-wave potential is 59 mV more negative but 47 mV more positive than that of the commercial Pt/C in acidic and alkaline electrolytes,*** full cell performance test results show that the aFe@AC sample is a promising candidate for direct methanol fuel *** study provides a general method to prepare catalysts with a certain type of active site and definite numbers.

关键词： atomic Fe-N4 site controllable synthesis fuel cells oxygen reduction reaction

One-step In-situ Synthesis of Vacancy-rich CoFe2O4@Defective Graphene Hybrids as Bifunctional Oxygen Electrocatalysts for Rechargeable Zn-Air Batteries

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Chemical Research in Chinese Universities 2020年第3期36卷 479-487页

作者： WANG X in ZHUANG Linzhou JIA Yi ZHANG Lijie yanG Qin XU Wenjia yanG Dongjiang yan xuecheng ZHANG Longzhou ZHU Zhonghua BROWN Christopher L YUAN Pei YAO Xiangdong School of Environment and Science ami Queensland Micro-and Nanotechnology CentreGriffith UniversityNathan CampusQueensland 4111Australia School of Chemistry Physics and Mechanical EngineeringQueensland University of TechnologyBrisbaneQueensland 4000Australia Collaborative Innovation Center for Mahne Biomass Fibers Materials ami Textiles of Shandong ProvinceInstitute of Marine Biobased MaterialsCollege of Environmental Science and EngineeringQingdao UniversityQingdao 266071P.R.China National Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou 350002P.R.China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun 130012P.R.China

Developing efficient catalysts toward both oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is the core task for rechargeable metal-air *** integration of two active components should be an effective method to produce the bifunctional catalysts in principle,traditional techniques still can not attain fine tunable surface structure during material-hybridization ***,we present a facile short-time in-situ argon(Ar)plasma strategy to fabricate a high-performance bifunctional hybrid catalyst of vacancy-rich CoFe2O4 synergized with defective graphence(r-CoFe2O4@DG).Reflected by the low voltage gap of 0.79V in two half-reaction measurements,the striking capability to catalyze ORR/OER endows it excellent and durable performance in rechargeable Zn-air batteries,with a maximum power density of 155.2mW/cm^2 and robust stablility(up to 60h).Further experimental and theoretical studies validate its remarkable bifunctional energetics root from plasma-induced surface vacancy defects and interfacial charge polarization between DG and CoFe2O4.

关键词： Defect CoFe2O4 Oxygen reduction Oxygen evolution Zn-air battery

鱼腥草添加对人工感染维氏气单胞菌锦鲤鳃部部分免疫指标的影响

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天津农学院学报 2024年第1期31卷 61-65页

作者：吕兆君尤禄涵仇钧仪李建胜闫学成陈成勋天津农学院水产学院天津市水产生态及养殖重点实验室天津300392 Indian Springs School Alabama 35124 宁河区农村社会事业发展服务中心天津301500

为探讨鱼腥草对人工感染维氏气单胞菌锦鲤鳃部部分免疫指标的影响,选取锦鲤96尾随机分两组,C组锦鲤投喂添加6‰鱼腥草的饲料,K组投喂基础日粮作为对照。分别饲养14 d后空腹24 h,通过腹腔进行人工感染维氏气单胞菌,于0、1、2、4 d进行采... 详细信息

为探讨鱼腥草对人工感染维氏气单胞菌锦鲤鳃部部分免疫指标的影响,选取锦鲤96尾随机分两组,C组锦鲤投喂添加6‰鱼腥草的饲料,K组投喂基础日粮作为对照。分别饲养14 d后空腹24 h,通过腹腔进行人工感染维氏气单胞菌,于0、1、2、4 d进行采样,检测鳃部的炎性因子(Il-4,Il-10)和免疫球蛋白(Ig T)。结果表明:K组四个时间段IL-4、IL-10和IgT含量差异均不显著(P>0.05);C组IL-4含量1 d和2 d时显著高于0 d、4 d(P<0.05),且高于K组;IL-10含量1,2,4 d时显著高于0 d(P<0.05),且均高于K组;IgT含量1 d与2 d高于4 d且显著高于0 d(P<0.05),且1 d与2 d时C组高于K组。说明前期鱼腥草饲养对细菌感染锦鲤鳃部免疫具有一定的提升作用。

关键词：鱼腥草锦鲤 IL-4 IL-10 IgT

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浅谈对铝压铸件表面的抛丸清理

特种铸造及有色合金 1998年第1期18卷 32-34页

作者：阎学成青岛华青铸造机械股份有限公司

针对铝合金压铸件表面的清理要求，分析抛丸清理的特点、所用设备的种类，对所选用的弹丸作了分析与推荐。

关键词：铝压铸件抛丸清理弹丸