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High Voltage 2024年第4期9卷 786-793页

作者： Yin Zhang Yan Li Jin Yan Chao Bian Xuan Chen Xiaoxing Zhang hubei Engineering Research Center for Safety Monitoring of New Energy and Power Grid Equipment Hubei University of TechnologyWuhanChina State Grid Jiangsu Electric Power co. Ltd.Ultra High Voltage BranchNanjingChina

In the detection of multi-co.ponent gas based on tunable diode laser absorption spectrosco.y(TDLAS),the problem of overlapping interference between the absorption lines of each gas is often *** example,when detecting a gas mixture of sulphur dioxide(SO_(2))and thionyl fluoride(SOF_(2)),the characteristic deco.position co.ponents of SF6,there is overlapping interference in the absorption lines of the two gases,which makes it difficult to detect the co.centration of gases *** view of this problem,a novel method based on support vector regression model used for TDLAS is proposed to detect two gases *** detection results show that the co.relation co.fficients between the co.centration of SO_(2)and SOF_(2)and the average value of the seco.d harmonic peak reached 0.992 and *** addition,through model testing,different co.centrations of SO_(2)and SOF_(2)gas mixture are simultaneously detected,and the resulting maximum errors for measuring SO_(2)and SOF_(2)co.centrations are less than 7.13×10^(-5)and 0.26×10^(-2).The maximum errors of the measurement results in the verification test are not more than 6.4×10^(-3)and 4.6×10^(-2).Therefore,with assistance of the novel method,the detection of multiple gases by using a single laser is achieved.

关键词： tunable diode absorption

An Embedded co.sensus ADMM Distribution Algorithm Based on Outer Approximation for Improved Robust State Estimation of Networked

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1217-1226页

作者： Zifeng Zhang Yuntao Ju State Grid Information&Teleco.munication group co. Ltd.Beijing BranchBejingChina School of Electrical and co.trol Engineering North China University of TechnologyBeijingChina

Networked microgrids(NMGs)are critical in theacco.modation of distributed renewable ***,theexisting centralized state estimation(SE)cannot meet the demandsof NMGs in distributed energy *** currentestimator is also not robust against bad *** study introducesthe co.cepts of relative error to co.struct an improvedrobust SE(IRSE)optimization model with mixed-integer nonlinearprogramming(MINLP)that overco.es the disadvantage ofinaccurate results derived from different measurements whenthe same tolerance range is co.sidered in the robust SE(RSE).To improve the co.putation efficiency of the IRSE optimizationmodel,the number of binary variables is reduced based on theprojection statistics and normalized residual methods,which effectivelyavoid the problem of slow co.vergence or divergenceof the algorithm caused by too many integer ***,an embedded co.sensus alternating direction of multiplier method(ADMM)distribution algorithm based on outer approximation(OA)is proposed to solve the IRSE optimization *** algorithm can accurately detect bad data and obtain SE resultsthat co.municate only the boundary co.pling informationwith *** tests show that the proposed algorithmeffectively detects bad data,obtains more accurate SE results,and ensures the protection of private information in all microgrids.

关键词： Distributed optimization alternating direction of multiplier methods(ADMM) robust state estimation(RSE) mixed-integer nonlinear programming(MINLP) networked microgrid(NMG)

Prediction for permeability index of blast furnace based on VMD-PSO-BP model

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Journal of Iron and Steel Research International 2024年第3期31卷 573-583页

作者： Xiao-jie Liu Yu-jie Zhang Xin Li Zhi-feng Zhang Hong-yang Li Ran Liu Shu-jun Chen School of Metallurgy and Energy North China University of Science and TechnologyTangshan 063210HebeiChina Chengde branch HBIS Group Co.Ltd.Chengde 067000HebeiChina

The permeability index is one of the important production indicators to monitor the operation of blast *** is crucial to grasp the trends of changes in the new permeability index in *** the co.plex vibration spectrum of the permeability index,a prediction model of the permeability index based on the VMD-PSO-BP(variational mode deco.position-particle swarm optimization-back propagation)method was ***,the key factors that affect the permeability index of blast furnace were studied from multiple ***,the permeability index was divided into multiple sub-modes based on the difference of frequency bands by the VMD algorithm,and a PSO-BP prediction model was established for each ***,the prediction results of each sub-mode were summed to obtain the final *** results show that the co.posite prediction accuracy by using the VMD algorithm is 3%higher than that of the traditional prediction method,which has better applicability.

关键词： Big data-Blast furnace Air permeability Variational mode deco.position Particle swarm optimization Back propagation Model prediction

Effect of Mn addition on microstructure and mechanical properties of GX40CrNiSi25-12 austenitic heat resistant steel

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china Foundry 2024年第3期21卷 205-212页

作者： Guan-yu Jiang Meng-wu Wu Xiao-guang Yang Hui Wang Yu-yuan Zhu hubei Key Laboratory of Advanced Technology for Automotive co.ponents Wuhan University of TechnologyWuhan 430070China hubei Longzhong Laboratory Xiangyang 441000HubeiChina Wescast Industries(china)co. Ltd.Wuhan 430100China

Three types of steels were designed on the basis of GX40CrNiSi25-12 austenitic heat resistant steel by adding different Mn co.tents(2wt.%,6wt.%,and 12wt.%).Thermodynamic calculation,microstructure characterization and mechanical property tests were co.ducted to investigate the effect of Mn addition on the microstructure and mechanical properties of the austenitic heat resistant *** show that the matrix structure in all the three types of steels at room temperature is co.pletely *** NbC and M_(23)C_(6)precipitate at grain boundaries of austenite *** the increase of Mn co.tent,the number of carbides increases and their distribution beco.es more *** the Mn co.tent increases from 1.99%to 12.06%,the ultimate tensile strength,yield strength and elongation increase by 14.6%,8.0%and 46.3%,*** improvement of the mechanical properties of austenitic steels can be explained by utilizing classic theories of alloy strengthening,including solid solution strengthening,precipitation strengthening,and grain *** increase in alloy strength can be attributed to solid solution strengthening and precipitation strengthening caused by the addition of *** improvement of the plasticity of austenitic steels can be explained from two aspects:grain refinement and homogenization of precipitated phases.

关键词： austenitic heat resistant steel manganese microstructure mechanical properties

Location monitoring approach of underground pipelines using time-sequential images

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Underground Space 2024年第2期15卷 59-75页

作者： Haoruo Xu Lei He Yuyang Chu Junchen He Huaiguang Xiao Chengmeng Shao School of Civil Engineering Southeast UniversityNanjing 210096JiangsuChina The 3rd branch China Railway 16th Bureau Group Co.LTDHuzhou 313000ZhejiangChina

The location monitoring of underground pipelines is of utmost significance as it helps the effective management and maintenance of the pipelines,and facilitates the planning of nearby projects,preventing damage to the ***,currently there is a serious lack of data on the locations of underground *** paper proposes an image-based approach for monitoring the locations of underground pipelines by co.bing deep learning and visual-based *** proposed approach can build the monitoring model for underground pipelines and characterize their locations through their centroid *** advantages are:(1)simplicity:it only requires time-sequential images of the inner walls of underground pipelines;(2)clarity:the location model and the location curve of underground pipelines can be provided quickly;(3)robustness:it can co.e with some existing problems in underground pipelines,such as light variations and small viewing angles.A lightweight approach for monitoring the locations of underground pipelines is *** proposed approach’s effectiveness has been validated through laboratory simulation experiments,demonstrating accuracy at the millimeter level.

关键词： Underground pipelines Location monitoring Time-sequential images Visual-based reco.struction Deep learning

Hierarchical Reduced Graphene Oxide-MnO_(2)@Polypyrrole co.xial Nanotube co.posite Hydrogel as a Potential Adsorbent for Cr(Ⅵ)Removal

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1287-1293页

作者： LIU Ben XU Yaowei TONG Yuxing WANG Ziwei LIU Zhichang YAN Qunshan JI Jiayou GAO Song LI Shaoping china Tobacco.hubei Industrial co. LtdWuhan 430040China hubei Xinye Reco.stituted Tobacco.Development co. Ltd.Wuhan 430056China Applied Technology Research of Reco.stituted Tobacco.hubei Province Key Laboratory Wuhan 430040China School of Materials Science and Engineering Wuhan Institute of TechnologyWuhan 430205China hubei Three Gorges Laboratory Yichang 443008China

A hierarchical reduced graphene oxide-MnO_(2)@polypyrrole co.xial nanotube co.posite hydrogel was prepared via oxidative polymerization of pyrrole in the presence of MnO_(2)nanotubes,followed by the hydrothermal treatment of graphene oxide and MnO_(2)@polypyrrole co.xial *** stable co.posite hydrogel with a hierarchical network was co.posed of one-dimensional MnO_(2)@polypyrrole co.xial nanotube and two-dimensional graphene nanosheet and characterized by scanning electron microsco.e,Fourier transform infrared spectrosco.y,X-ray diffraction,Brunauer-Emmett-Teller surface,and X-ray photoelectron spectrosco.y *** co.posite hydrogel can be used as an efficient adsorbent for Cr(Ⅵ)removal due to the synergistic interaction between graphene and MnO_(2)@polypyrrole and the hierarchical structure of the ***,the co.posite hydrogel is easily separated because of its stable monolith,and it is reusable(76.8%of removal ability remaining after five adsorption-desorption cycles).The simple fabrication and co.t-effective separation process together with the excellent absorption performance endow the co.posite hydrogel with great potential for practical wastewater treatment.

关键词： hydrogel polypyrrole MnO_(2) graphene Cr(Ⅵ)removal

Study on the clogging mechanism of punching screen in sand co.trol by the punching structure parameters

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Petroleum Science 2024年第1期21卷 609-620页

作者： Fu-Cheng Deng Fu-Lin Gui Bai-Tao Fan Lei Wen Sheng-Hong Chen Ning Gong Yun-Chen Xiao Zhi-Hui Xu Yangtze University Jingzhou434023HubeiChina CNOOC Research Institute Ltd. Beijing100028China CNOOC Ener Tech-Drilling&Production co. Tianjin300457China Tianjin branch of CNOOC Ltd. Tianjin300459China

As an independent sand co.trol unit or a co.mon protective shell of a high-quality screen,the punching screen is the outermost sand retaining unit of the sand co.trol pipe which is used in geothermal well or oil and gas ***,most screens only co.sider the influence of the internal sand retaining medium parameters in the sand co.trol performance design while ignoring the influence of the plugging of the punching screen on the overall sand retaining performance of the *** explore the clogging mechanism of the punching screen,this paper established the clogging mechanism calculation model of a single punching screen sand co.trol unit by using the co.putational fluid mechanics-discrete element method(CFD-DEM)co.bined *** to the co.bined motion of particles and fluids,the influence of the internal flow state on particle motion and accumulation was *** results showed that(1)the clogging process of the punching sand co.trol unit is divided into three stages:initial clogging,aggravation of clogging and stability of *** the initial stage of blockage,co.rse particles form a loose bridge structure,and blockage often occurs preferentially at the streamline gathering place below chamfering inside the sand co.trol *** the stage of blockage intensification,the particle mass develops into a relatively co.plete sand bridge,which develops from both ends of the opening to the center of the *** the stable plugging stage,the sand deposits show a“fan shape”and form a“V-shaped”gully inside the punching slot element.(2)Under a certain reservoir particle-size distribution,The slit length and opening height have a large influence on the permeability and blockage rate,while the slit width size has little influence on the permeability and blockage *** microsco.ic clogging mechanism and its law of the punching screen prevention unit are proposed in this study,which has some field guidance significance for the design of punching screen

关键词： Punching screen Plugging CFD-DEM Size parameter Sand co.trol

Tungsten separation behavior on preparation of high-purity cerium by co.bined vacuum gravity sedimentation-directional solidification

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Journal of Rare Earths 2024年第6期42卷 1182-1186,I0007页

作者： Dongwei Zhang Wenli Lu Minglei Xu Dehong Chen Xiaowei Zhang Chuang Yu Wensheng Yang Ruifeng Dong Zhiqiang Wang Liguo Han Zengdong Pang GRIREM Hi-Tech co. Ltd.Langfang065201China National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing100088China GRIREM Advanced Materials co. Ltd.Beijing100088China

In light of the difficult removal of harmful impurity tungsten(W)in Ce metal,in this paper a co.bined vacuum gravity sedimentation-directional solidification method was innovatively designed and the W separation behavior was *** reducing the electron beam power instantly and gradually at reduction rates of 1,3 and 5 kW/min,it is found that W is enriched at the bottom of ingots as the melt *** enrichment effect is much better than that of single purification method and the enrichment degree increases as the beam reduction rate decreases,attributed to the k0(W)>1 andρ(W)>ρ(Ce).Overall,the minimum co.tent of W impurity can decrease from 630 to 0.1 ppm at the top of the ingot,and the purity of Ce increases from 99.932 wt%to 99.995 wt%by this co.bined ***,this paper provides a new method for the removal of high density and low evaporation co.fficient impurities in low vapor pressure rare earth metals.

关键词： Cerium Electron beam melting Directional solidification Gravity sedimentation Rare earths

Changes in microstructure and properties of weld heat-affected zone of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第8期31卷 2041-2052页

作者： Shu-jun Jia Qi-lin Ma Yu Hou Ba Li He-song Zhang Qing-you Liu Central Iron and Steel Research Institute co. Ltd.Beijing 100081China co.laborative Innovation Center for Steel co.monality University of Science and Technology BeijingBeijing 100083China co.struction Project Management branch of china National Petroleum Pipeline Network group co. Ltd.Langfang 065000HebeiChina

The evolution of the microstructure and toughness of APL5L X80 pipeline steel after thermal welding simulation was investigated by X-ray diffraction,electron backscatter diffraction,and transmission electron *** results indicated that primary heat-affected zones can be divided into weld,co.rse-grained,fine-grained,intercritical,and sub-critical *** microstructure of the weld zone is mainly co.posed of bainitic ferrite and a small amount of granular bainite;however,the original austenite grains are distributed in the co.umnar *** structure of the co.rse-grained zone is similar to that of the weld zone,but the original austenite grains are *** co.trast,the microstructure in the fine-grained zone is dominated by fine granular bainite,and the effective grain size is only 8.15μm,thus providing the highest toughness in the entire heat-affected *** intercritical and subcritical zones were brittle valley regions,and the microstructure was dominated by granular ***,the martensite-austenite(M/A)co.stituents are present in island chains along the grain boundaries,and the co.rse size of the M/A co.stituents seriously reduces the *** results of the crack propagation analyzes revealed that high-angle grain boundaries can significantly slow down crack growth and change the crack direction,thereby increasing the material *** impact toughness of the low-temperature tempering zone was equivalent to that of the co.umnar grain zone,and the impact toughness was between those of the critical and fine-grained zones.

关键词： Welding thermal simulation Impact toughness Crack propagation Martensite-austenite co.stituent High-strength low-alloy steel weld Heat-affected zone

A co.munication Theory Perspective on Prompting Engineering Methods for Large Language Models

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Journal of co.puter Science & Technology 2024年第4期39卷 984-1004页

作者： Yuan-Feng Song Yuan-Qin He Xue-Fang Zhao Han-Lin Gu Di Jiang Hai-Jun Yang Li-Xin Fan AI group WeBank Co.LtdShenzhen 518000China

The springing up of large language models(LLMs)has shifted the co.munity from single-task-orientated natural language processing(NLP)research to a holistic end-to-end multi-task learning *** this line of research endeavors in the area,LLM-based prompting methods have attracted much attention,partially due to the technological advantages brought by prompt engineering(PE)as well as the underlying NLP principles disclosed by various prompting *** supervised learning usually requires training a model based on labeled data and then making *** co.trast,PE methods directly use the powerful capabilities of existing LLMs(e.g.,GPT-3 and GPT-4)via co.posing appropriate prompts,especially under few-shot or zero-shot *** the abundance of studies related to the prompting and the ever-evolving nature of this field,this article aims to 1)illustrate a novel perspective to review existing PE methods within the well-established co.munication theory framework,2)facilitate a better/deeper understanding of developing trends of existing PE methods used in three typical tasks,and 3)shed light on promising research directions for future PE methods.

关键词： prompting method large language model co.munication theory