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Nutrient transport following water transfer through the world's largest water diversion channel

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Journal of Environmental Sciences 2024年第1期135卷 703-714页

作者： Yuanhui cheng Hong Zhang Wei Yin State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085 China Changjiang Water Resources Protection Institute Wuhan 430051China University of Chinese Academy of Sciences Beijing 100049China

Nutrient levels in the artificial channel constructed for the Middle Route Project are significant indicators of water quality safety and aquatic ecological integrity for this large,interbasin ***,the distribution and transport of nutrients along the channel were poorly *** on a time-series dataset as well as mass balance and material flow analysis methods,the water and nutrient transport fluxes in the Middle Route of the South-to-North Water Diversion Project were identified in this *** results indicate that the nutrient concentrations varied considerably with time,but there was no significant difference among the 30 stations of the main *** temperature difference was the major factor in the large fluctuations of water quality indicators over *** nutrient loadings varied with the water volume outputs from the main channel to the waterreceiving *** deposition was an important source of nutrients in the main channel,accounting for 9.13%,20.6%,and 0.635%of the nitrogen,phosphorus,and sulfur input from the Danjiangkou Reservoir,*** 2021,a net accumulation of 988 tons of N,29 tons of P,and 2,540 tons of S,respectively,were present in the main *** increase of these external and internal nutrient loadings would cause water quality fluctuation and deterioration in some local sections of the main *** study quantified the spatial and temporal patterns of nutrient transport in the Middle Route and revealed the ecological effects on the aquatic environment,assisting authorities on the project to develop effective water conservation strategies.

关键词： Nutrient transport Spatiotemporal patterns The Middle Route The South-to-North Diversion Project Hydro-ecological effects Water-receiving cities

Determining an optimal control strategy for anthropogenic VOC emissions in China based on source emissions and reactivity

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Journal of Environmental Sciences 2024年第2期136卷 248-260页

作者： Ruipeng Wang Xiaoqi Wang Shuiyuan cheng Jiaxian Zhu Xinyu Zhang Long cheng Kai Wang Key Laboratory of Beijing on Regional Air Pollution Control Faculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

An evidence-based control strategy for emission reduction of VOC sources can effectively solve the regional PM2.5and O3compound pollution in *** estimated the anthropogenic VOC emission inventory in China in 2018 and established a source profile database containing 129 sources based on localized detection and the latest research ***,the distribution of the ozone formation potential(OFP)and secondary organic aerosol formation potential(SOAFP)for emission sources was ***,priority control routes for VOC emission sources were proposed for different *** VOC emissions in China reached 27,211.8 Gg in 2018,and small passenger cars,industrial protective coatings,biomass burning,heavy trucks,printing,asphalt paving,oil storage and transportation,coking,and oil refining were the main *** protective coatings,small passenger cars,and biomass burning all contributed significantly to OFP and *** in emission reduction control should be given to industrial protective coatings,small passenger cars,heavy trucks,coking,printing,asphalt paving,chemical fibers,and basic organic chemical sources over the medium and long term in *** addition,the priority control route for VOC emission sources should be adjusted according to the variations in VOC emission characteristics and regional differences,so as to obtain the maximum environmental benefits.

关键词： Volatile organic compounds Anthropogenic emission inventory Reactivity Emission projection Priority control route

Higher-dimensional integrable deformations of the classical Boussinesq-Burgers system

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Communications in Theoretical Physics 2024年第6期76卷 1-12页

作者： Xiaoyu cheng Qing Huang School of Mathematics Northwest UniversityXi'an 710127China

In this paper,the(1+1)-dimensional classical Boussinesq-Burgers(CBB)system is extended to a(4+1)-dimensional CBB system by using its conservation laws and the deformation *** Lax integrability,symmetry integrability and a large number of reduced systems of the new higher-dimensional system are ***,for illustration,an exact solution of a(1+1)-dimensional reduced system is constructed from the viewpoint of Lie symmetry analysis and the power series method.

关键词： classical Boussinesq-Burgers system higher-dimensional system deformation algorithm Lax pair conservation law

Analysis of destructive effect of Zn on carbon brick and way of Zn into carbon brick

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Journal of Iron and Steel Research(International) 2024年第6期31卷 1344-1354页

作者： Peng-bo Liu Shu-sen cheng Yu-qing Xue Xiao-man cheng Zhao Liu University of Science and Technology Beijing Beijing 100083China Ministry of Ironmaking Shangdong Taishan Steel Group Co.Ltd.Taian 271000ShandongChina

The service life of a blast furnace depends largely on the degree of damage to the carbon brick in the *** brick and ramming material in the hearth of a 1780 m3 blast furnace after shutdown were sampled and *** was found that the substances in the cracks of the carbon brick near and above the taphole were ZnO and Zn_(2)SiO_(4),whereas the substances in the cracks of the carbon brick below the taphole were *** reaction of Zn with CO,SiO_(2),and Fes generates ZnO,Zn_(2)SiO_(4),and ZnS,resulting in volume expansion,which is an important reason for the cracking of carbon ***,several obvious Zn vapor flow channels were found in the ramming material,through which Zn vapor could enter the carbon brick,causing damage to the carbon *** the compactness of the ramming material is beneficial to preventing Zn vapor from entering the carbon brick through the voids in the ramming material,reducing the destructive effect of Zn on the carbon brick and further extending the service life of the blast furnace.

关键词： Zn Blast furnace Carbon brick Ramming material Crack

Collectively induced transparency and absorption in waveguide quantum electrodynamics with Bragg atom arrays

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Communications in Theoretical Physics 2024年第8期76卷 21-30页

作者： Haolei cheng Wei Nie Center for Joint Quantum Studies and Department of Physics School of Science Tianjin University Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology Tianjin University

Collective quantum states, such as subradiant and superradiant states, are useful for controlling optical responses in many-body quantum systems. In this work, we study novel collective quantum phenomena in waveguide-coupled Bragg atom arrays with inhomogeneous *** atoms without free-space dissipation, collectively induced transparency is produced by destructive quantum interference between subradiant and superradiant states. In a large Bragg atom array, multi-frequency photon transparency can be obtained by considering atoms with different frequencies. Interestingly, we find collectively induced absorption(CIA) by studying the influence of free-space dissipation on photon transport. Tunable atomic frequencies nontrivially modify decay rates of subradiant states. When the decay rate of a subradiant state equals to the free-space dissipation, photon absorption can reach a limit at a certain frequency. In other words, photon absorption is enhanced with low free-space dissipation, distinct from previous photon detection schemes. We also show multi-frequency CIA by properly adjusting atomic frequencies. Our work presents a way to manipulate collective quantum states and exotic optical properties in waveguide quantum electrodynamics(QED) systems.

关键词： Bragg atom array collective quantum states photon absorption waveguide quantum electrodynamics

The Minimum Centroid Branch Spanning Tree Problem

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Journal of the Operations Research Society of China 2024年第2期12卷 528-539页

作者： Hao Lin cheng He School of Science Henan University of TechnologyZhengzhou450001HenanChina

For a spanning tree T of graph G,the centroid of T is a vertex v for which the largest component of T-v has as few vertices as *** number of vertices of this component is called the centroid branch weight of *** minimum centroid branch spanning tree problem is to find a spanning tree T of G such that the centroid branch weight is *** application to design of communication networks,the loads of all branches leading from the switch center should be as balanced as *** this paper,we prove that the problem is strongly NP-hard even for bipartite ***,the problem is shown to be polynomially solvable for split graphs,and exact formulae for special graph familis,say Kn_(1),n_(2),...,n_(k)and P_(m)×P_(n),are presented.

关键词： Spanning tree optimization Centroid branch-NP-hardness Polynomial-time algorithm

Prescribed-Time Fully Distributed Nash Equilibrium Seeking Strategy in Networked Games

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 261-263页

作者： cheng Qian Lei Ding the Institute of Advanced Technology for Carbon Neutrality College of Automation&the College of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjing 210023China IEEE

Dear Editor, This letter is concerned with prescribed-time fully distributed Nash equilibrium seeking for networked games under directed graphs. An adaptive algorithm is proposed to ensure the convergence of all players to the Nash equilibrium without requiring any knowledge of global parameters. Moreover, it is theoretically proved that the convergence time of the proposed seeking strategy can be predefined based on practical requirements. Finally, a numerical example is presented to validate the effectiveness of the proposed method.

关键词： parameters seeking prescribed

Highlights in recent wireless power IC research

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Journal of Semiconductors 2024年第4期45卷 5-7页

作者： cheng Huang Junyao Tang Iowa State University AmesIowa50011USA

Wireless power transfer(WPT)has been a popular topic in power integrated circuit(IC)designs in the past *** slogan"cutting the last wire"presented in ISSCC’15[1],WPT is poised to take over many wired power deliveries applica-tions today,just like what happened to wireless communica-tion *** the years,WPT has become more mature and more wirelessly charged or powered products have become available on the *** mini review intends to summarize recent breakthroughs in WPT inte-grated circuits(IC)research.

关键词： WPT power wireless

Prediction and Output Estimation of Pattern Moving in Non-Newtonian Mechanical Systems Based on Probability Density Evolution

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 515-536页

作者： cheng Han Zhengguang Xu School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing100083China Key Laboratory of Knowledge Automation for Industrial Processes University of Science and Technology BeijingBeijing100083China

A prediction framework based on the evolution of pattern motion probability density is proposed for the output prediction and estimation problem of non-Newtonian mechanical systems,assuming that the system satisfies the generalized Lipschitz *** a complex nonlinear system primarily governed by statistical laws rather than Newtonian mechanics,the output of non-Newtonian mechanics systems is difficult to describe through deterministic variables such as state variables,which poses difficulties in predicting and estimating the system’s *** this article,the temporal variation of the system is described by constructing pattern category variables,which are non-deterministic *** pattern category variables have statistical attributes but not operational attributes,operational attributes are assigned to them by posterior probability density,and a method for analyzing their motion laws using probability density evolution is ***,a data-driven form of pattern motion probabilistic density evolution prediction method is designed by combining pseudo partial derivative(PPD),achieving prediction of the probability density satisfying the system’s output *** on this,the final prediction estimation of the system’s output value is realized by minimum variance unbiased ***,a corresponding PPD estimation algorithm is designed using an extended state observer(ESO)to estimate the parameters to be estimated in the proposed prediction *** effectiveness of the parameter estimation algorithm and prediction method is demonstrated through theoretical analysis,and the accuracy of the algorithm is verified by two numerical simulation examples.

关键词： Non-newtonian mechanical systems prediction and estimation pattern moving probability density evolution pseudo partial derivative