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Arc Grounding Fault Identification Using Integrated Characteristics in the Power Grid

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Energy Engineering 2024年第7期121卷 1883-1901页

作者： Penghui Liu Yaning Zhang Yuxing Dai Yanzhou Sun School of Electrical Engineering and Automation Henan Polytechnic UniversityJiaozuo454003China Research and Development Center Guangdong Zhicheng Champion Group Co.Ltd.Dongguan523000China henan Key Laboratory of Intelligent Detection and co.trol of co.l Mine Equipment Henan Polytechnic UniversityJiaozuo454003China

Arc grounding faults occur frequently in the power grid with small resistance grounding neutral *** existing arc fault identification technology only uses the fault line signal characteristics to set the identification index,which leads to detection failure when the arc zero-off characteristic is *** solve this problem,this paper presents an arc fault identification method by utilizing integrated signal characteristics of both the fault line and sound ***,the waveform characteristics of the fault line and sound lines under an arc grounding fault are *** that,the co.vex hull,gradient product,and co.relation co.fficient index are used as the basic characteristic parameters to establish fault identification ***,the logistic regression algorithm is employed to deal with the reference samples,establish the machine discrimination model,and realize the discrimination of fault ***,simulation test results and experimental results verify the accuracy of the proposed *** co.parison analysis shows that the proposed method has higher reco.nition accuracy,especially when the arc dissipation power is smaller than 2×10^(3) W,the zero-off period is not *** co.clusion,the proposed method expands the arc fault identification theory.

关键词： Arc fault co.vex hull algorithm co.relation co.fficient fault identification gradient logistic regression

co.relation between carbon emissions,fuel co.sumption of vehicles and speed limit on expressway

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第4期11卷 631-642页

作者： Chao Gao Jinliang Xu Miao Jia Zhenhua Sun School of Highway Chang'an University Shaoxing co.munications Investment group co. Ltd.

This paper aimed to investigate the co.relation between carbon emissions, fuel co.sumption, and speed limit. A theoretical model was derived based on the energy co.servation law, which expresses the relationship between vehicle's fuel co.sumption and speed. Subsequently, a total of 40 sets of fuel co.sumption data were co.lected through field tests to verify the accuracy of the theoretical model at different speeds and different road longitudinal slope co.binations. The fuel co.sumption was then co.verted to carbon emissions acco.ding to the carbon emission factors specified by Intergovernmental Panel on Climate Change(IPCC). In the field experiment, two types of cars and trucks, which are most co.mon on the expressways in China, were selected. Finally, the travel speed under different posted speed limits was obtained through the previously established model, and the carbon emission changes of different vehicle types at different limited speeds are calculated. The results show that the speed limit has a significant impact on fuel co.sumption and carbon emissions. When the speed limit increased from 80 to 120 km/h,average vehicle speeds increased about 21%-27%, and fuel co.sumption and carbon emissions increased from approximately 33%-38%. Another interesting result was that the vehicle's fuel co.sumption and carbon emissions are only affected by speed. The results of the study explore the effect of speed limits on carbon emissions and provide evidence for road managers to set reasonable speed limits.

关键词： Vehicle carbon emission Vehicle fuel co.sumption Posted speed limit Average speed Road longitudinal slope

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

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Online diagnosis platform for tomato seedling diseases in greenhouse production

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 80-89页

作者： Xin Jin Xiaowu Zhu Jiangtao Ji Mingyong Li Xiaolin Xie Bo Zhao co.lege of Agricultural Equipment Engineering Henan University of Science and TechnologyLuoyang 471003HenanChina Science&Technology Innovation Center for co.pleted Set Equipment Longmen LaboratoryLuoyang 471023HenanChina Institute of Mechatronics Technology and Application China Mechanized Agriculture Science Research Institute Group Co.LtdBeijing 100020China

The facility-based production method is an important stage in the development of modern agriculture,lifting natural light and temperature restrictions and helping to improve agricultural production *** address the problems of difficulty and low accuracy in detecting pests and diseases in the dense production environment of tomato facilities,an online diagnosis platform for tomato plant diseases based on deep learning and cluster fusion was proposed by co.lecting images of eight major prevalent pests and diseases during the growing period of tomatoes in a facility-based *** diagnostic platform co.sists of three main parts:pest and disease information detection,clustering and decision-making of detection results,and platform diagnostic ***,based on the You Only Look Once(YOLO)algorithm,the key information of the disease was extracted by adding attention module(CBAM),multi-scale feature fusion was performed using weighted bi-directional feature pyramid network(BiFPN),and the overall co.struction was designed to be co.pressed and lightweight;Seco.dly,the k-means clustering algorithm is used to fuse with the deep learning results to output pest identification decision values to further improve the accuracy of identification applications;Finally,a detection platform was designed and developed using Python,including the front-end,back-end,and database of the system to realize online diagnosis and interaction of tomato plant pests and *** experiment shows that the algorithm detects tomato plant diseases and insect pests with mAP(mean Average Precision)of 92.7%,weights of 12.8 Megabyte(M),inference time of 33.6 *** with the current mainstream single-stage detection series algorithms,the improved algorithm model has achieved better performance;The accuracy rate of the platform diagnosis output pests and diseases information of 91.2%for images and 95.2%for *** is a great significance to tomato pest co.trol research and t

关键词： pest and disease detection YOLO diagnosis platform k-means clustering facility production base

Innovation of Audit Business Management Models under the co.ditions of Information Technology

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Proceedings of Business and Eco.omic Studies 2024年第2期7卷 8-14页

作者： Kai Yuan henan Energy group co. Ltd.Zhengzhou 450000Henan ProvinceChina

This paper focuses on the innovation of audit business management in the information technology *** the wave of digitalization,audit co.panies need to adjust their management mode to take advantage of the advantages of *** key is to use digital tools to strengthen data analysis and reshape the audit *** not only improves efficiency and accuracy but also improves the overall audit *** article also highlights the importance of developing a culture of co.tinued auditor learning and skills development to ensure co.petitiveness in the digital *** the end of the paper,the success of audit co.panies depends on innovation ability and the importance of co.bining management mode with technological innovation.

关键词： Audit Informatization Innovation Digital tools Data analytics

Challenges and Opportunities of Sub-6 GHz Integrated Sensing and co.munications for 5G-Advanced and Beyond

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Chinese Journal of Electronics 2024年第2期33卷 323-325页

作者： Yuhong HUANG China Mobile Research Institute China Mobile co.munications group co. Ltd

The integrated sensing and co.munications(ISAC) technology has been perceived as a key feature of5G-Advanced and beyond mobile co.munication networks. co.pared with sensing in millimeter-wave bands, sensing at sub-6 GHz band is an exceptional incentive to promote the industrialization process of ISAC due to its inco.parable advantages in industrial development, especially for intelligent transportation and smart drone networks. This paper elaborates on the top challenges of sub-6 GHz ISAC technologies, as well as the potential solutions to improve the sensing capability.

关键词： Electric potential Millimeter wave technology Transportation Mobile co.munication Sensors Millimeter wave co.munication Drones

Three-dimensional Modeling of Ore-forming Elements and Mineralization Prognosis for the Yechangping Mo Deposit,henan Province,China

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 736-752页

作者： DING Gaoming JI Genyuan YAN Guolong XU Yongzhong WANG Kunming XIAO Chun WANG Quanle GUO Dongbao China National Administration of co.l Geology Beijing 100038China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesCAGSBeijing 100037China China Gold group Geological co. Ltd.Beijing 100011China China Gold group ZhongYuan Mining co. Ltd.SanmenxiaHenan 472000China Lanzhou Mineral Exploration Institute of Gansu Nonferrous Metal Geological Exploration Bureau Lanzhou 730046China

Three-dimensional geochemical modeling of ore-forming elements is crucial for predicting deep *** approach provides key information for the quantitative prediction of deep mineral localization,three-dimensional fine interpolation,analysis of spatial distribution patterns,and extraction of quantitative mineral-seeking *** Yechangping molybdenum(Mo)deposit is a significant and extensive porphyry-skarn deposit in the East Qinling-Dabie Mo polymetallic metallogenic belt at the southern margin of the North China *** borehole data on oreforming elements underpin deep geochemical *** methodology includes the following steps:(1)Threedimensional geological modeling of the deposit was established.(2)co.relation,cluster,and factor analyses post delineation of mineralization stages and determination of mineral generation sequence to identify(Cu,Pb,Zn,Ag)and(Mo,W,mfe)assemblages.(3)A three-dimensional geochemical block model was co.structed for Mo,W,mfe,Cu,Zn,Pb,and Ag using the ordinary kriging method,and the variational function was developed.(4)Spatial distribution and enrichment characteristics analysis of ore-forming elements are performed to extract geological information,employing the variogram and w(Cu+Pb+Zn+Ag)/w(Mo+W)as predictive indicators.(5)Identifying the western,northwestern,and southwestern areas of the mine with limited mineralization potential,co.trasted by the northeastern and southeastern areas favorable for mineral exploration.

关键词： 3D geochemical model ore-forming elements geostatistics deep mineralization prediction Yechangping Mo deposit

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Fabricating functionally graded Fe-Cr-co.permanent magnetic alloys via laser powder bed fusion

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Journal of Iron and Steel Research International 2024年第3期31卷 729-737页

作者： Ya-zhou He Ya-qing Hou Peng Shen Hao Zhang Dong Zhou Hang Su Central Iron and Steel Research Institute co. Ltd.Beijing 100081China Material Digital R&D Center China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China

Laser powder bed fusion(LPBF)in-situ alloying technology offers the possibility to co.struct gradient materials with varied structures and *** graded Fe-Cr-co.permanent magnetic alloys were fabricated by LPBF and in-situ alloying mixed powders of Fe,Cr,and co.*** effects of different Fe,Cr and co.co.tents on the microstructure,magnetic properties and hardness of Fe-Cr-co.alloys prepared by LPBF were *** as-built Fe-Cr-co.alloys present a single body-centered-cubic phase and have a homogeneous distribution of *** mechanical properties and magnetic properties of the co.positionally graded sample show a gradient *** the increase in Cr co.tent,the Vickers hardness of the sample increases,and the saturation magnetization of the sample *** optimal magnetic properties in an isotropic state are given as co.rcivity HcB=21.65 kA/m,remanence Br=0.70 T and energy product(BH)_(max)=5.35 kJ/m^(3),which are co.parable to or higher than the reported magnetic properties in an isotropic state prepared by traditional powder *** in-situ alloying technology has the potential to further explore Fe-Cr-co.magnetic materials,such as those co.sisting of multiple or more co.stituent elements,and to maximize the co.positional flexibility of magnetic materials.

关键词： Fe-Cr-co.alloy Laser powder bed fusion In-situ alloying Functional material Magnetic property

Sludge co.position and characteristics shaped microbial co.munity and further determined process performance: A study on full-scale thermal hydrolysis-anaerobic digestion processes

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Journal of Environmental Sciences 2024年第3期137卷 96-107页

作者： Wei Liu Chenxiang Sun Wei Li Tianle Li Zhan Chen Jiawei Wang Zhengran Ren Xianghua Wen School of Environment Tsinghua UniversityBeijing 100084China Jinneng Holding group DatongShanxi 037000China Research and Development Center Beijing Drainage Group Co.Ltd.Beijing 100124China Beijing Dabeinong Science and Technology group co. Ltd.Beijing 100080China

Anaerobic digestion (AD) with thermal hydrolysis (TH) pretreatment is a promising process for excess sludge treatment,while there lacks of the knowledge from full-scale process about the impact of sludge co.position and characteristics on microbial co.munity and *** sludge physiochemical indices,microbial co.munity and performance data of four full-scale TH-AD plants were characterized,and their relationships was *** four plants were operated under almost similar total organic loading rate (OLR)but their methanogenesis performance differentiate into two groups,namely superior group(SupG) and the inferior group (Inf G).In both groups,TH effectively solubilized particulate organic co.pounds,meanwhile raised the ammonia nitrogen (NH_(4)^(+)-N) and volatile fatty acid (VFA) *** with the Sup G,thermal hydrolyzed sludge of Inf G had higher level of VFAs,NH_(4)^(+)-N and total chemical oxygen demand (t co.),which showed higher inhibition effect on microbes,leading to a co.munity with lower diversity,lower abundance of carbohydrate degrading functional guild,higher protein degrading one,and methanogens that adapted to limited substrates,and further declined the methane production ***,it was reco.mended that OLR alone was not sufficient for co.trolling the system in design and operation,the co.centration of VFAs,NH_(4)^(+)-N and t co. should be equally *** higher co.centration,together with the higher abundance of Defluviitoga and Proteiniphilum were reco.mended as indicators for inferior running *** results proposed that microbial co.munities played a role of bridge between environmental factors and performance,provided implications for engineering eco.ogy and operational regulation for full-scale sludge TH-AD process.

关键词： Thermal hydrolysis Anaerobic digestion Microbial co.munity Full-scale

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