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Reliability of a Multicomponent Stress-strength Model Based on a Bivariate Kumaraswamy Distribution with Censored Data

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 478-507页

作者： Cong-hua cheng School of Mathematics and Statistics Zhaoqing UniversityZhaoqing 526061China

In this paper,we consider a system which has k statistically independent and identically distributed strength components and each component is constructed by a pair of statistically dependent elements with doubly type-II censored *** elements(X1,Y1),(X2,Y2),…,(Xk,Yk)follow a bivariate Kumaraswamy distribution and each element is exposed to a common random stress T which follows a Kumaraswamy *** system is regarded as operating only if at least s out of k(1≤s≤k)strength variables exceed the random *** multicomponent reliability of the system is given by Rs,k=p(at least s of the(Z1,…,Zk)exceed T)where Zi=min(Xi,Yi),i=1,…,*** Bayes estimates of Rs,k have been developed by using the Markov Chain Monte Carlo methods due to the lack of explicit *** uniformly minimum variance unbiased and exact Bayes estimates of Rs,k are obtained analytically when the common second shape parameter is *** asymptotic confidence interval and the highest probability density credible interval are constructed for Rs,*** reliability estimators are compared by using the estimated risks through Monte Carlo simulations.

关键词： stress-strength model bivariate Kumaraswamy distribution multicomponent reliability doubly Type-II censored scheme interval estimation

Explainable artificial intelligence models for mineral prospectivity mapping

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Science China Earth Sciences 2024年第9期67卷 2864-2875页

作者： Renguang ZUO Qiuming cheng Ying XU Fanfan YANG Yihui XIONG Ziye WANG Oliver p.KREUZER State Key Laboratory of Geological processes and Mineral Resources China University of Geosciences School of Earth Sciences and Engineering Sun Yat-sen University Corporate Geoscience Group (CGSG) Economic Geology Research Centre (EGRU) College of Science and EngineeringJames Cook University

Mineral prospectivity mapping(MpM) is designed to reduce the exploration search space by combining and analyzing geological prospecting big data. Such geological big data are too large and complex for humans to effectively handle and interpret. Artificial intelligence(AI) algorithms, which are powerful tools for mining nonlinear mineralization patterns in big data obtained from mineral exploration, have demonstrated excellent performance in MpM. However, AI-driven MpM faces several challenges, including difficult interpretability, poor generalizability, and physical inconsistencies. In this study, based on previous studies, we devised a novel workflow that aims to constructing more transparent and explainable artificial intelligence(XAI) models for MpM by embedding domain knowledge throughout the AI-driven MpM, from input data to model design and model output. This newly proposed approach provides strong geological and conceptual leads that guide the entire AI-driven MpM model training process, thereby improving model interpretability and performance. Overall, the development of XAI models for MpM is capable of embedding prior and expert knowledge throughout the modeling process, presenting a valuable and promising area for future research designed to improve MpM.

关键词： Artificial intelligence Mineral prospectivity mapping Geological prospecting big data Domain knowledge Interpretability

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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

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

Ce-and La-doped polymetallic layered double hydroxides for enhanced oxygen evolution reaction performance at high current density

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Science China Chemistry 2024年第8期67卷 2586-2598页

作者： Rinel R.Kimaka p. ping Wang Miao He Senyao Meng Jiasai Yao Huawei Li cheng Yang Zhenxing Li State Key Laboratory of Heavy Oil processing College of New Energy and MaterialsChina University of Petroleum(Beijing)Beijing 102249China

polymetallic layered double hydroxides are promising cost-effective catalysts for the oxygen evolution reaction(OER) due to their versatile anionic and cationic tunability. Nevertheless, several challenges persist, notably, issues related to low electrical conductivity, poor catalytic activity, and stability, especially at high current density. Herein, we report the design of Ce-and Ladoped Co Ni Fe-layered double hydroxide(Ce La Co Ni Fe-LDH) nanosheets through a facile and scalable in situ self-assembly strategy that displays enhanced OER activity. Experimental and theoretical investigations provide insights into the impact of Ceand La-doping by comparing Ce Co Ni Fe-LDH, La Co Ni Fe-LDH, and pristine Co Ni Fe-LDH, all synthesized using the same methodology. These results reveal that doping Ce^(3+)and La^(3+)into Co Ni Fe-LDH substantially improves its electronic structure,resulting in enhanced conductivity, more oxygen vacancies(Vo), electron interaction, and active site formation. Consequently,significantly reduced overpotentials of 175, 314, and 424 m V at 10, 100, and 500 m A cm^(-2), respectively, and a highly stable current density of 120 h in 1 M KOH were achieved. Notably, these performance metrics surpass those of unmodified LDHs and are competitive with many lanthanide-doped transition metal-based LDH electrocatalysts, as well as noble metal catalysts like ruthenium catalysts. This work represents a pioneering effort in doping Ce^(3+)and La^(3+)ions into a functional Co Ni Fe-based electrocatalyst, offering inspiring OER performance and scalability potential.

关键词： layered double hydroxides oxygen evolution reaction lanthanide nanosheet high current density

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Scattering for the Radial Schrodinger Equation with Combined power-type and Choquard-type Nonlinearities

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1029-1041页

作者： Ying WANG cheng Bin XU The Graduate School of China Academy of Engineering physics Beijing 100088P.R.China School of Mathematics and Statistics Qinghai Normal UniversityXining 810008P.R.China

In this paper,we show the scattering of the radial solution for the nonlinear Schrodinger equation with combined power-type and Choquard-type nonlinearities iut+△u=λ1|u|p1-1u+λ2(Iα*|u|^(p2))|u|p^(2-2)*** the energy space H^(1)(R^(N))forλ_(1)λ_(2)=-*** establish a scattering criterion for radial solution together with Morawetz estimate which implies the scattering *** show that the defocusing perturbation terms does not determine the scattering solution in energy space.

关键词： Schrodinger equation Choquard-type Scattering theory

Continuous Orbit Equivalence of Semigroup Actions

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1581-1598页

作者： Xiang Qi QIANG cheng Jun HOU School of Mathematical Science Yangzhou UniversityYangzhou 225002P.R.China

We introduce notions of continuous orbit equivalence and its one-sided version for countable left Ore semigroup actions on compact spaces by surjective local homeomorphisms,and characterize them in terms of the corresponding transformation groupoids and their operator *** particular,we show that two essentially free semigroup actions on totally disconnected compact spaces are continuously orbit equivalent if and only if there is a canonical abelian subalgebra preserving C^(∗)-isomorphism between the associated transformation groupoid C^(∗)-*** also give some examples of orbit equivalence,consider the special case of semigroup actions by homeomorphisms and relate continuous orbit equivalence of semigroup actions to that of the associated group actions.

关键词： Semigroup action continuous one-sided orbit equivalence continuous orbit equivalence groupoid C^(∗)-algebras

Understanding the molecular crossroads in acute liver failure:A pathway to new therapies

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World Journal of Gastroenterology 2024年第23期30卷 2931-2933页

作者： Chun-Yao cheng Wen-Rui Hao Tzu-Hurng cheng Department of Medical Education National Taiwan University HospitalTaipei 100225Taiwan Division of Cardiology Department of Internal MedicineShuang Ho HospitalMinistry of Health and WelfareTaipei Medical UniversityNew Taipei 23561Taiwan Division of Cardiology Department of Internal MedicineSchool of MedicineCollege of MedicineTaipei Medical UniversityTaipei 11002Taiwan Department of Biochemistry School of MedicineCollege of MedicineChina Medical UniversityTaichung 404333Taiwan

In this editorial we comment on the article published in a recent issue of the World Journal of *** liver failure(ALF)is a critical condition characterized by rapid hepatocellular injury and organ dysfunction,and it often necessitates liver transplant to ensure patient *** research has eluci-dated the involvement of distinct cell death pathways,namely ferroptosis and pyroptosis,in the pathogenesis of *** is driven by iron-dependent lipid peroxidation,whereas pyroptosis is an inflammatory form of cell death;both pathways contribute to hepatocyte death and exacerbate tissue *** comprehensive review explores the interplay between ferroptosis and pyroptosis in ALF,highlighting the role of key regulators such as silent information regulator sirtuin *** from clinical and preclinical studies provide valuable perspectives on the dysregulation of cell death pathways in ALF and the therapeutic potential of targeting these *** across multiple disciplines is essential for translating the experimental insights into effective treatments for this life-threatening condition.

关键词： Silent information regulator sirtuin 1 Ferroptosis pyroptosis p53/glutathione peroxidase 4/gasdermin D Acute liver failure

Room-temperature ferrimagnetism and size-modulated electronic structures in two-dimensional cluster-based metal-organic frameworks

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Science China Chemistry 2024年第4期67卷 1334-1340页

作者： Jing cheng Xingxing Li Jinlong Yang Key Laboratory of precision and Intelligent Chemistry University of Science and Technology of ChinaHefei 230026China Department of Chemical physics University of Science and Technology of ChinaHefei 230026China Hefei National Research Center for physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China

Cluster-assembled materials have attracted particular attention for their complex hierarchical structures and unique ***,the majority of cluster-based assemblies developed so far are either non-magnetic or only exhibit magnetic ordering with a relatively low Curie temperature,limiting their applications in ***,two-dimensional(2D)cluster-assembled materials with room-temperature magnetism remain highly *** this purpose,based on first principles calculations,we design a series of thermodynamically stable 2D cluster-based metal-organic frameworks(MOFs)Fe_(n)-(pyz)(n=1-6)by utilizing Fenmetal clusters as nodes and nitrogen-containing pyrazine ligands as organic *** 2D cluster-based MOFs exhibit robust ferrimagnetic ordering due to the strong d-p direct exchange interaction between d-electron spin of Fe_(n)(n=1-6)clusters and charge transfer-induced p-electron spin of pyrazine *** particular,the ferrimagnetic Curie temperatures are well above room temperature(up to 836 K).Additionally,altering the size of Fe_(n)clusters in Fe_(n)-(pyz)(n=1-6)MOFs results in diverse functional spintronic properties,including bipolar magnetic semiconductors,half semiconductors and Dirac half ***,these 2D assembled MOFs possess sizable magnetic anisotropy energies,up to 9.16 me V per formula.

关键词： metal-organic framework two-dimensional material half metal bipolar magnetic semiconductor magnet