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Quantitative estimation of bubble volume fraction of submarine seep plumes by modeling seismic oceanography data

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Journal of Oceanology and Limnology 2023年第2期41卷 673-686页

作者： Tonggang HAN Jiangxin CHEN Leonardo AZEVEDO Bingshou HE Huaning XU Rui YANG key Lab of Submarine Geosciences and Prospecting Techniques Ministry of EducationOcean University of ChinaQingdao 266100China key laboratory of Gas Hydrate Ministry of Natural ResourcesQingdao Institute of Marine GeologyQingdao 266071China laboratory for Marine Mineral Resources Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China CERENA DECivilInstituto Superior TécnicoUniversidade de LisboaAv.Rovisco PaisLisbon 1049-001Portugal

Submarine seep plumes are a natural phenomenon in which different types of gases migrate through deep or shallow subsurface sediments and leak into seawater in pressure *** detected using acoustic data,the leaked gases frequently exhibit a flame-like *** numerically modelled the relationship between the seismic response characteristic and bubble volume fraction to establish the bubble volume fraction in the submarine seep *** show that our models are able to invert and predict the bubble volume fraction from field seismic oceanography data,by which synthetic seismic sections in different dominant frequencies could be numerically simulated,seismic attribute sections(e.g.,instantaneous amplitude,instantaneous frequency,and instantaneous phase)extracted,and the correlation between the seismic attributes and bubble volume fraction be quantitatively determined with functional *** instantaneous amplitude is positively correlated with bubble volume fraction,while the instantaneous frequency and bubble volume fraction are negatively *** addition,information entropy is introduced as a proxy to quantify the relationship between the instantaneous phase and bubble volume *** the bubble volume fraction increases,the information entropy of the instantaneous phase increases rapidly at the beginning,followed by a slight upward trend,and finally ***,under optimal noise conditions,the bubble volume fraction of submarine seep plumes can be inverted and predicted based on seismic response characteristics in terms of seismic attributes.

关键词： seismic oceanography submarine seep plumes bubble volume fraction seismic response characteristics seismic attribute analysis quantitative analysis

Tracking performance limitations of MIMO discrete-time networked control systems with multiple constraints

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science China(Information sciences) 2023年第8期66卷 267-268页

作者： Xiaowei JIANG Bin ZHANG Xiangyong CHEN Huaicheng YAN School of Automation China University of Geosciences key laboratory of Industrial Internet of Things & networked Control Ministry of Education Hubei key laboratory of Advanced Control and Intelligent Automation for Complex Systems Engineering Research Center of Intelligent technology for Geo-Exploration Ministry of Education School of Automation and Electrical Engineering Linyi University key laboratory of Smart Manufacturing in Energy Chemical Process of the Ministry of Education

Dear editor,networked control systems(NCSs) have attracted widespread attention in some fields because they offer the advantages of reduced cabling, greater resource sharing,and ease of installation and maintenance [1]. However, in an unreliable network environment, network constraints can significantly limit the performance of NCSs.

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DFE-GCN: Dual Feature Enhanced Graph Convolutional network for Controversy Detection

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Computers, Materials & Continua 2023年第10期77卷 893-909页

作者： Chengfei Hua Wenzhong Yang Liejun Wang Fuyuan Wei KeZiErBieKe HaiLaTi Yuanyuan Liao College of Software Xinjiang UniversityUrumqi830000China key laboratory of Signal Detection and Processing in Xinjiang Uygur Autonomous Region Xinjiang UniversityUrumqi830000China key laboratory of Multilingual Information technology in Xinjiang Uygur Autonomous Region Xinjiang UniversityUrumqi830000China

With the development of social media and the prevalence of mobile devices,an increasing number of people tend to use social media platforms to express their opinions and attitudes,leading to many online *** online controversies can severely threaten social stability,making automatic detection of controversies particularly *** controversy detection methods currently focus on mining features from text semantics and propagation ***,these methods have two drawbacks:1)limited ability to capture structural features and failure to learn deeper structural features,and 2)neglecting the influence of topic information and ineffective utilization of topic *** light of these phenomena,this paper proposes a social media controversy detection method called Dual Feature Enhanced Graph Convolutional network(DFE-GCN).This method explores structural information at different scales from global and local perspectives to capture deeper structural features,enhancing the expressive power of structural ***,to strengthen the influence of topic information,this paper utilizes attention mechanisms to enhance topic features after each graph convolutional layer,effectively using topic *** validated our method on two different public datasets,and the experimental results demonstrate that our method achieves state-of-the-art performance compared to baseline *** the Weibo and Reddit datasets,the accuracy is improved by 5.92%and 3.32%,respectively,and the F1 score is improved by 1.99%and 2.17%,demonstrating the positive impact of enhanced structural features and topic features on controversy detection.

关键词： Controversy detection graph convolutional network feature enhancement social media

Hydrologic implications of the isotopic kinetic fractionation of open-water evaporation

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science China Earth sciences 2018年第10期61卷 1523-1532页

作者： Wei XIAO Yufei QIAN Xuhui LEE Wei WANG Mi ZHANG Xuefa WEN Shoudong LIU Yongbo HU Chengyu XIE Zhen ZHANG Xuesong ZHANG Xiaoyan ZHAO Fucun ZHANG Yale-NUIST Center on Atmospheric Environment & Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment technology(CICAEET) Nanjing University of Information Science & Technology School of Forestry and Environmental Studies Yale University Jiangsu key laboratory of Agricultural Meteorology Nanjing University of Information Science & Technology key laboratory of Ecosystem network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences

The kinetic fractionation of open-water evaporation against the stable water isotope H_2 ^(18)O is an important mechanism underlying many hydrologic studies that use ^(18)O as an isotopic tracer. A recent in-situ measurement of the isotopic water vapor flux over a lake indicates that the kinetic effect is much weaker(kinetic factor 6.2‰) than assumed previously(kinetic factor14.2‰) by lake isotopic budget studies. This study investigates the implications of the weak kinetic effect for studies of deuterium excess-humidity relationships, regional moisture recycling, and global evapotranspiration partitioning. The results indicate that the low kinetic factor is consistent with the deuterium excess-humidity relationships observed over open *** moisture recycling rate in the Great Lakes region derived from the isotopic tracer method with the low kinetic factor is a much better agreement with those from atmospheric modeling studies than if the default kinetic factor of 14.2‰ is used. The ratio of transpiration to evapotranspiration at global scale decreases from 84±9%(with the default kinetic factor) to 76±19%(with the low kinetic factor), the latter of which is in slightly better agreement with other non-isotopic partitioning results.

关键词：土壤水分蒸发蒸腾损失总量运动效果非同位素开水蒸汽流动地区性再循环循环率

Detonation Shock Dynamics Relations for RDX-TNT Based Cast Explosives

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Journal of Beijing Institute of technology 2008年第2期17卷 138-142页

作者： SHAKEEL Abbas Rofi 黄风雷 State key laboratory of Explosion science and technology Beijing Institute of Technology

RDX and TNT based explosives are very useful in performing research and development works especially when complex shaping of an assembly is required due to their molding capability and the range of ratios in which they can be mixed. In this paper, for these compositions, detonation shock dynamics （DSD） relations between normal detonation velocity D. and detonation wave curvature κ are determined for RDX： TNT explosives in weight ratios 40：60, 50：50 and 60：40. Experiments are performed with 50 mm diameter rate sticks of approximately 200 mm length using high speed rotating mirror camera and time measurement probes. The results show that first order DSD relation is indeed representative of these explosives. The slope of this relation increases by increasing TNT contents in these explosives. Going from 40% to 60% TNT, the data show an increase of more than 100% in negative slope of Dn-κ relation.

关键词： DSD curvature high-speed photography diverging/converging wave fronts

Low contact resistivity and long-term thermal stability of Nb0.8Ti0.2FeSb/Ti thermoelectric junction

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Journal of Materials science & technology 2020年第5期40卷 113-118页

作者： Zhijie Huang Li Yin Chaoliang Hu Jiajun Shen Tiejun Zhu Qian Zhang Kaiyang Xia Jiazhan Xin Xinbing Zhao State key laboratory of Silicon Materials and School of Materials science and Engineering Zhejiang UniversityHangzhou 310027China Department of Materials science and Engineering Institute of Materials Genome&Big DataHarbin Institute of TechnologyShenzhen 518055China

Although half-Heusler compounds are quite promising for thermoelectric power generation,there is only limited research on the interfacial structure between metal electrode and half-Heusler compounds for device *** work reports on the characteristics of Nb0.8Ti0.2Fe Sb/Ti junction and its evolution behavior during 973 *** Nb0.8Ti0.2Fe Sb/Ti interface consists of one Ti0.9Fe0.1 layer and one Fe-poor *** is an Ohmic contact and a low contact resistivity(0.15μΩcm^-2)in this junction,on account of the matching of working functions between Nb0.8Ti0.2Fe Sb and Ti0.9Fe0.1 *** high doping of Ti high carrier concentration in Nb Fe Sb matrix leads to a high carrier concentration,which results in inducing a large tunneling current at this *** aging treatment at 973 K,the Fe-poor layer and the Ti0.9 Fe0.1 layer continues to expand,resulting in the increase of the thickness of the interfacial layer and the contact *** interfacial electrical is only 1.9μcm^-2 after 25 days’*** thickness of the interface layer has a good linear relation with the square root of aging time,which firmly indicates that the growth of the layer is determined by mutual diffusion of Fe and Ti atoms across the *** low contract resistivity and long-time thermal stability demonstrate the great potential of Nb0.8Ti0.2Fe Sb/Ti thermoelectric junction in high efficiency half-Heusler TE devices.

关键词： Thermoelectric materials Half-Heusler alloys Electrode Contact resistivity Thermal stability

Numerical Simulation and Analysis on Velocity Profiles of Jet Projectile Charge

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Journal of Beijing Institute of technology 2009年第4期18卷 379-383页

作者：黄风雷 Shakeel Abbas Rofi State key laboratory of Explosion science and technology Beijing Institute of Technology

Jet projectile charge （JPC） is a relatively new type of perforating jet mainly used for defeating concrete targets. Velocity profile is an important parameter to investigate the penetration and performance of JPC. Since limited information such as X-ray radiographs and penetration depth can be obtained through the JPC experiment, the numerical simulation and further methodology are needed to depict the mechanism of JPC. This paper describes a mathematical approach based on Matlab to determine JPC velocity profile at various stand offs using three sets of jet data from numerical simulations. X-ray radiographs experimental results have been obtained at two time instants for two selected JPC design to verify the numerical accuracy. The velocity profiles by mathematical approach and simulation show good accordance. The number of experiments can be reduced by numerical simulation and analysis of velocity profiles. This approach can be generalized to any such system where explosive-metal interaction results in formation of jets.

关键词： jet projectile charge jet velocity profile stand off X-ray measurement Matlab

Adaptive price adjustment method for used mobile phone based on dual deep fuzzy networks

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science China(Technological sciences) 2022年第6期65卷 1330-1337页

作者： HAN HongGui LI Ying DU YongPing Faculty of Information technology Beijing University of TechnologyBeijing 100124China Beijing key laboratory of Computational Intelligence and Intelligent System Beijing 100124China Engineering Research Center of Digital Community Ministry of EducationBeijing 100124China

Aiming at solving the problem that it is challenging to choose the appropriate price adjustment strategy according to the market fluctuations,an adaptive price adjustment method based on dual deep fuzzy networks(DDFN)is ***,a price adjustment model based on DDFN is *** interactively learning the recycling market environment,the description of the mapping relationship between the market environment information and the price adjustment action is ***,based on a greedy strategy to calculate the optimal price adjustment action,it is possible to make small adjustments based on the preliminary estimated value of the waste mobile phone,and complete the judgment of the mobile phone recycling ***,based on the market feedback,the gradient descent algorithm is used to update parameters of the model to improve the *** proposed adaptive price adjustment method based on DDFN is applied to the actual transaction process,and the results show that the proposed method can ensure the accuracy and reliability of the adjustment results of the mobile phone recycling price.

关键词： used mobile phones recycle adaptive price adjustment dual deep fuzzy network

Multivariable identification of membrane fouling based on compacted cascade neural network

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Chinese Journal of Chemical Engineering 2023年第1期53卷 37-45页

作者： Kun Ren Zheng Jiao Xiaolong Wu Honggui Han Faculty of Information technology Beijing University of TechnologyBeijing 100124China Engineering Research Center of Digital Community Ministry of EducationBeijing 100124China Beijing key laboratory of Computational Intelligence and Intelligent System Beijing 100124China

The membrane fouling phenomenon,reflected with various fouling characterization in the membrane bioreactor(MBR)process,is so complicated to *** paper proposes a multivariable identification model(MIM)based on a compacted cascade neural network to identify membrane fouling ***,a multivariable model is proposed to calculate multiple indicators of membrane fouling using a cascade neural network,which could avoid the interference of the overlap ***,an unsupervised pretraining algorithm was developed with periodic information of membrane fouling to obtain the compact structure of ***,a hierarchical learning algorithm was proposed to update the parameters of MIM for improving the identification accuracy ***,the proposed model was tested in real plants to evaluate its efficiency and *** results have verified the benefits of the proposed method.

关键词： Membrane fouling Permeability Cascade neural networks Model Prediction