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Source analysis of dissolved heavy metals in the Shaying River Basin,China

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Journal of Groundwater Science and Engineering 2023年第4期11卷 408-421页

作者： Ya-wei Zhang Yun-tao Liu Zi-wen Wang Yu Cao xiao-ran Tu Di Cao Shuai Yuan xiao-man cheng Lian-sheng Zhang School of Environmental Studies China University of GeosciencesWuhan 430074China Henan Fifth Geological Exploration Institute Co. Ltd.Zhengzhou 450001China Henan Second Geological Survey Institute Co. Ltd.Zhengzhou 450001China Henan Rock and Mineral Testing Center Zhengzhou 450001China

Over the years,the Shaying River Basin has experienced frequent instances of river *** presence of numerous critical pollutant discharge enterprises and sewage-treatment plants in the vicinity of the Shaying River has transformed it a major tributary with relatively serious pollution challenge within the upper reaches of Huaihe River *** study the sources of manganese(Mn),chromium(Cr),nickel(Ni),arsenic(As),cadmium(Cd)and lead(Pb)in Shaying River water,123 sets of surface water samples were collected from 41 sampling points across the entire basin during three distinct phases from 2019 to 2020,encompassing normal water period,dry season and wet *** primary origins of heavy metals in river water were determined by analyzing the heavy metal contents in urban sewage wastewater,industrial sewage wastewater,groundwater,mine water,and the heavy metal contributions from agricultural non-point source *** analytical findings reveal that Mn primarily originates from shallow groundwater used for agricultural irrigation,While Cr mainly is primarily sourced from urban sewage treatment plant effluents,coal washing wastewater,tannery wastewater,and industrial discharge related to metal processing and *** is mainly contributed by urban sewage treatment plant effluents and industrial wastewater streams associated with machinery manufacturing and metal *** primarily linked to industrial wastewater,particularly from machinery manufacturing and metal processing facilities,while Pb is predominantly associated with urban sewage treatment plant effluents and wastewater generated in Pb processing and recycling *** research provides a crucial foundation for addressing the prevention and control of dissolved heavy metals at their sources in the Shaying River.

关键词： Industrial waste Urban sewage Mine water Agricultural non-point source pollution

Compound Product of Hypermatrices

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Journal of Systems Science & Complexity 2024年第1期37卷 169-183页

作者： cheng Daizhan MENG Min ZHANG xiao JI Zhengping Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China Department of Control Science and Engineering School of Electronics and Information EngineeringTongji UniversityShanghai 201210China National Center for Mathematics and Interdisciplinary Sciences Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100149China.

The semi-tensor product(STP)of matrices is generalized to multidimensional arrays,called the compound product of *** product is first defined for three-dimensional hypermatrices with compatible orders and then extended to general *** different types of hyperdeterminants are introduced and certain properties are *** Lie groups and Lie algebras corresponding to the hypermatrix products are ***,these results are applied to dynamical systems.

关键词： Compound semi-tensor product hyperdeterminants hypereigenvalues and hypereigenvectors hypergeneral linear groups hypermatrices.

Double stabilizations and convergence analysis of a second-order linear numerical scheme for the nonlocal Cahn-Hilliard equation

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Science China Mathematics 2024年第1期67卷 187-210页

作者： xiao Li Zhonghua Qiao cheng Wang Department of Applied Mathematics The Hong Kong Polytechnic UniversityHong KongChina Department of Mathematics The University of MassachusettsNorth DartmouthMA 02747USA

In this paper,we study a second-order accurate and linear numerical scheme for the nonlocal CahnHilliard *** scheme is established by combining a modified Crank-Nicolson approximation and the Adams-Bashforth extrapolation for the temporal discretization,and by applying the Fourier spectral collocation to the spatial *** addition,two stabilization terms in different forms are added for the sake of the numerical *** conduct a complete convergence analysis by using the higher-order consistency estimate for the numerical scheme,combined with the rough error estimate and the refined *** regarding the numerical solution as a small perturbation of the exact solution,we are able to justify the discrete?^(∞)bound of the numerical solution,as a result of the rough error ***,the refined error estimate is derived to obtain the optimal rate of convergence,following the established?∞bound of the numerical ***,the energy stability is also rigorously proved with respect to a modified *** proposed scheme can be viewed as the generalization of the second-order scheme presented in an earlier work,and the energy stability estimate has greatly improved the corresponding result therein.

关键词： nonlocal Cahn-Hilliard equation second-order stabilized scheme higher-order consistency analysis rough and refined error estimate

Reactor field reconstruction from sparse and movable sensors using Voronoi tessellation-assisted convolutional neural networks

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Nuclear Science and Techniques 2024年第5期35卷 173-185页

作者： He-Lin Gong Han Li Dunhui xiao Sibo cheng Paris Elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China School of Mathematical Sciences Tongji UniversityShanghai 200092China Department of Computing Data Science InstituteImperial College LondonLondon SW72AZUK

The aging of operational reactors leads to increased mechanical vibrations in the reactor *** vibration of the incore sensors near their nominal locations is a new problem for neutronic field *** field-reconstruction methods fail to handle spatially moving *** this study,we propose a Voronoi tessellation technique in combination with convolutional neural networks to handle this *** from movable in-core sensors were projected onto the same global field structure using Voronoi tessellation,holding the magnitude and location information of the *** convolutional neural networks were used to learn maps from observations to the global *** proposed method reconstructed multi-physics fields(including fast flux,thermal flux,and power rate)using observations from a single field(such as thermal flux).Numerical tests based on the IAEA benchmark demonstrated the potential of the proposed method in practical engineering applications,particularly within an amplitude of 5 cm around the nominal locations,which led to average relative errors below 5% and 10% in the L_(2) and L_(∞)norms,respectively.

关键词： Voronoi tessellation Field reconstruction Nuclear reactors Reactor physics On-line monitoring

A new method for evaluating wedges of steel plates and strips

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Journal of Iron and Steel Research(International) 2024年第7期31卷 1719-1735页

作者： xiao-bao Ma xiao-xin Ma Tao Wang Zhong-kai Ren Yu-cheng Ren College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Ministry of Education Engineering Research Center of Advanced Metal Composite Forming Technology and Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina China National Heavy Machinery Research Institute Co. Ltd.Xi'an 710018ShaanxiChina Faculty of Mechanical Engineering Hebei University of ArchitectureZhangjiakou 075000HebeiChina

To overcome the inaccuracy problem of the traditional wedge evaluation of steel plates and strips caused by the ran-domness of the thicknesses of two local points and improve the reliability of the wedge index,the double-centroid method for the wedge evaluation was proposed,and a model based on the centroid theory was ***,an integral model for the discrete thickness values of the cross-section profiles was *** discussion focused on the distinct characteristics of the two-point method,asymmetric method,and double-centroid method in evaluating the asymmetric distribution of *** three methods were employed to evaluate the wedge values of both the theoretical and measured cross-sections of steel plates and strips,and the accuracies of three wedge evaluation models were analyzed and *** results showed that the double-centroid method objectively reflects the degree and variation characteristics of the wedge values of the cross-sections of steel plates and strips,and this method is feasible,reliable,and outstanding.

关键词： Steel plate and strip Wedge Two-point method Double-centroid method Reliability

An improved algorithm for retrieving thin sea ice thickness in the Arctic Ocean from SMOS and SMAP L-band radiometer data

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Acta Oceanologica Sinica 2024年第3期43卷 127-138页

作者： Lian He Senwen Huang Fengming Hui xiao cheng School of Geospatial Engineering and Science Sun Yat-Sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Key Laboratory of Comprehensive Observation of Polar Environment(Sun Yat-Sen University) Ministry of EducationZhuhai 519082China

The aim of this study was to develop an improved thin sea ice thickness(SIT)retrieval algorithm in the Arctic Ocean from the Soil Moisture Ocean Salinity and Soil Moisture Active Passive L-band radiometer *** SIT retrieval algorithm was trained using the simulated SIT from the cumulative freezing degree days model during the freeze-up period over five carefully selected regions in the Beaufort,Chukchi,East Siberian,Laptev and Kara seas and utilized the microwave polarization ratio(PR)at incidence angle of 40°.The improvements of the proposed retrieval algorithm include the correction for the sea ice concentration impact,reliable reference SIT data over different representative regions of the Arctic Ocean and the utilization of microwave polarization ratio that is independent of ice *** relationship between the SIT and PR was found to be almost stable across the five selected *** SIT retrievals were then compared to other two existing algorithms(i.e.,UH_SIT from the University of Hamburg and UB_SIT from the University of Bremen)and validated against independent SIT data obtained from moored upward looking sonars(ULS)and airborne electromagnetic(EM)induction *** results suggest that the proposed algorithm could achieve comparable accuracies to UH_SIT and UB_SIT with root mean square error(RMSE)being about 0.20 m when validating using ULS SIT data and outperformed the UH_SIT and UB_SIT with RMSE being about 0.21 m when validatng using EM SIT *** proposed algorithm can be used for thin sea ice thickness(<1.0 m)estimation in the Arctic Ocean and requires less auxiliary data in the SIT retrieval procedure which makes its implementation more practical.

关键词： Arctic sea ice sea ice thickness remote sensing Soil Moisture Active Passive(SMAP) Soil Moisture Ocean Salinity and Soil(SMOS)

A Possible X-ray Quasi-periodic Oscillation in the Narrow-line Seyfert 1 Galaxy Mrk 142

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Research in Astronomy and Astrophysics 2024年第6期24卷 191-200页

作者： xiao-Gu Zhong Jian-cheng Wang Yong-Yun Chen xiao-Ling Yu College of Physics and Electronic Engineering Qujing Normal UniversityQujing 655011China Yunnan Observatories Chinese Academy of SciencesKunming 650216China

A possible quasi-periodic oscillation(QPO) at frequency 7.045 × 10^(-5) Hz is found in the narrow-line Seyfert 1galaxy Mrk 142 in the data of XMM-Newton collected on 2020 April *** find that the QPO signal is statistically significantly larger than the 5σ level and highly coherent with quality factor Q > 5 at the 0.3–10 keV band by using the method of the Lomb–Scargle Periodogram,the Weighted Wavelet Z-transform and the *** analyze the data in 0.3–0.6 keV,0.6–1 keV,1–3 keV and 3–10 keV energy bands,and find obvious QPO signals at 0.3–0.6 keV and 1–3 keV *** then analyze the time-average spectra and time variability at the QPO frequency of 7.045 × 10^(-5) Hz,and use a model to fit *** find that the QPO signal mainly comes from the X-ray hot corona.

关键词： X-rays:galaxies galaxies:Seyfert accretion accretion disks radiation mechanisms:general

Data augmentation method for insulators based on Cycle-GAN

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Journal of Electronic Science and Technology 2024年第2期22卷 36-47页

作者： Run Ye Azzedine Boukerche xiao-Song Yu cheng Zhang Bin Yan xiao-Jia Zhou School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu611731China School of Electrical Engineering and Computer Science University of OttawaOttawaK1N6N5Canada Yangtze River Delta Research Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou313001China

Data augmentation is an important task of using existing data to expand data *** generative countermeasure network technology to realize data augmentation has the advantages of high-quality generated samples,simple training,and fewer restrictions on the number of generated ***,in the field of transmission line insulator images,the freely synthesized samples are prone to produce fuzzy backgrounds and disordered samples of the main insulator *** solve the above problems,this paper uses the cycle generative adversarial network(Cycle-GAN)used for domain conversion in the generation countermeasure network as the initial framework and uses the self-attention mechanism and channel attention mechanism to assist the conversion to realize the mutual conversion of different insulator *** attention module with prior knowledge is used to build the generation countermeasure network,and the generative adversarial network(GAN)model with local controllable generation is built to realize the directional generation of insulator belt defect *** experimental results show that the samples obtained by this method are improved in a number of quality indicators,and the quality effect of the samples obtained is excellent,which has a reference value for the data expansion of insulator images.

关键词： Data expansion Deep learning Generate confrontation network Insulator

Impact of nutritional support on immunity,nutrition,inflammation,and outcomes in elderly gastric cancer patients after surgery

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2175-2182页

作者： xiao-Wan Chen xiao-Chun Guo Fen cheng Department of Gastrointestinal Surgery Hubei Cancer HospitalWuhan 430079Hubei ProvinceChina Department of Gastroenterology The First People’s Hospital of Jiangxia DistrictWuhan 430200Hubei ProvinceChina

BACKGROUND Postoperative rehabilitation of elderly patients with gastric cancer has always been the focus of clinical *** the intervention by a full-course nutritional support team can have a positive impact on the postoperative immune function,nutritional status,inflammatory response,and clinical outcomes of this special population has not yet been fully *** To evaluate the impact of full-course nutritional support on postoperative comprehensive symptoms in elderly patients with gastric *** This is a retrospective study,including 60 elderly gastric cancer patients aged 70 years and above,divided into a nutritional support group and a control *** nutritional support group received full postoperative nutritional support,including individualized meal formulation,and intravenous and parenteral nutrition supplementation,and was regularly evaluated and adjusted by a professional nutrition *** control group received routine postoperative *** After intervention,the proportion of CD4+lymphocytes(25.3%±3.1%vs 21.8%±2.9%,P<0.05)and the level of immunoglobulin G(12.5 G/L±2.3 G/L vs 10.2 G/L±1.8 G/L,P<0.01)were significantly higher in the nutritional support group than in the control group;the changes in body weight(-0.5 kg±0.8 kg vs-1.8 kg±0.9 kg,P<0.05)and body mass index(-0.2±0.3 vs-0.7±0.4,P<0.05)were less significant in the nutritional support group than in the control group;and the level of C-reactive protein(1.2 mg/L±0.4 mg/L vs 2.5 mg/L±0.6 mg/L,P<0.01)and WBC count(7.2×10^(9)/L±1.5×10^(9)/L vs 9.8×10^(9)/L±2.0×10^(9)/L,P<0.01)were significantly lower in the nutritional support group than in the control *** addition,patients in the nutritional support group had a shorter hospital stay(10.3 d±2.1 d vs 14.8 d±3.6 d,P<0.05)and lower incidence of infection(15%vs 35%,P<0.05)in those of the control *** The intervention by the nutritional support team has a positive impact on postoperative immune function,

关键词： Elderly gastric cancer Postoperative Nutritional support Immune function Inflammatory response Clinical outcome