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Uniqueness Problem for the Backward Differential Equation of a Continuous-State Branching Process

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1825-1836页

作者： Pei Sen li zeng hu li School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100872P.R.China School of Mathematical Sciences Beijing Normal UniversityBeijing 100875P.R.China

The distributional properties of a multi-dimensional continuous-state branching process are determined by its cumulant semigroup,which is defined by the backward differential *** provide a proof of the assertion of Rhyzhov and Skorokhod(Theory ***.,1970)on the uniqueness of the solutions to the equation,which is based on a characterization of the process as the pathwise unique solution to a system of stochastic equations.

关键词： Continuous-state branching process multi-dimensional backward differential equation stochastic equation generator

Impact wear properties of dissimilar joints between bainitic frogs and pearlite rails

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Journal of Iron and Steel Research International 2024年第1期31卷 275-287页

作者： Pin-yong zeng Chun-guang Zuo Xiao-yu Zhang Wei li Tribology Research Institute Southwest Jiaotong UniversityChengdu610031SichuanChina

The impact wear behavior and damage mechanism of dissimilar welded joints between U26Mn frog and U75 V rail before and after normalizing treatment were studied by cyclic impact *** experiment indicated that the impact wear volume of the joints increased with the increasing number of impact *** main wear mechanisms include pitting wear,mild fatigue wear,delamination wear,and fatigue wear,and plastic deformation was the primary impact wear *** them,fatigue wear had the greatest influence on wear volume,while other wear mechanisms had limited *** impact wear resistance of the base material was better than that of the heat-affected *** treatment was beneficial to improving the impact wear resistance of welded joints owing to its effect to promote pearlite recovery,grain refinement,and uniform distribution of *** martensite generated in the rail welded joints aggravated the impact wear damage to the materials,which should be avoided.

关键词： Dissimilar welded joint Impact wear Bainitic steel damage mechanism Wear rate

Subclinical impairment of left ventricular myocardium function in type 2 diabetes mellitus patients with or without hypertension

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World Journal of Diabetes 2024年第6期15卷 1272-1279页

作者： zeng-guang Chen guang-An li Jun huang li Fan Department of Cardiology The Affiliated Changzhou Second People’s Hospital with Nanjing Medical UniversityChangzhou 213000Jiangsu ProvinceChina Department of Echocardiography The Affiliated Changzhou Second People’s Hospital with Nanjing Medical UniversityChangzhou 213000Jiangsu ProvinceChina

BACKGROUND Cardiovascular disease has been the leading cause of morbidity and mortality for type 2 diabetes mellitus(T2DM)patients over the last *** To determine whether layer-specific global longitudinal strain(GLS)combined with peak strain dispersion(PSD)can be used to assess left ventricle(LV)myocardium systolic dysfunction in T2DM patients or without hypertension(HP).METHODS We enrolled 97 T2DM patients,70 T2DM+HP patients and 101 healthy ***-specific GLS and PSD were calculated by EchoPAC software in apical three-,four-and two-chamber *** of the epimyocardial,middle-layer and endomyocardial(GLSepi,GLSmid,and GLSendo)were measured and *** operating characteristic analysis was performed to detect LV myocardium systolic dysfunction in T2DM *** There were significant differences in GLSepi,GLSmid,GLSendo,and PSD between healthy subjects,T2DM patients and T2DM patients with HP(PT2DM patients>T2DM with HP patients in the absolute values of GLSepi,GLSmid and GLSendo(Plic dysfunction in T2DM patients,however,the area under the curve(AUC)for layer-specific GLS and PSD combined was significantly higher than the AUCs for the individual indices(Plic dysfunction in T2DM patients,T2DM patients with HP.T2DM patients with HP have more severe LV myocardium systolic dysfunction than T2DM patients without HP and normal control *** combination of layer-specific GLS and PSD may provide additional prognostic information for T2DM patients with or without HP.

关键词： Type 2 diabetes mellitus Hypertension Speckle tracking echocardiography Global longitudinal strain Peak strain dispersion

The genesis and resource potential of gold deposits in the liaodong Peninsula

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Science China Earth Sciences 2024年第3期67卷 657-672页

作者： Rixiang Zhu Jin-hui YANG Gongwen WANG Qingdong zeng Guoqiang XUE Tao XU Xinghui li Peng ZHANG da LEI guang Zhu State Key Laboratory of lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Shenyang Center China Geological SurveyShenyang 110034China School of Resources and Environmental Engineering Hefei University of TechnologyHefei 230009China

Plenty of gold deposits related to Late Mesozoic craton destruction are widely distributed in eastern North China Craton. However, significant differences in research degrees, ore-forming characteristics, and proven reserves exist among different regions in the North China Craton. The liaodong Peninsula has similar regional geological characteristics to those of the Jiaodong Peninsula, with both experiencing craton destruction during Late Mesozoic, but the two areas have substantial differences in terms of gold mineralization and the proven gold resources. Based on regional geology, Mesozoic magmatictectonic evolution and ore geology, combined with integrated geophysical exploration and big data AI resource prediction, in this paper, we propose that the ore-forming materials of Late Mesozoic gold deposits in liaodong were mainly originated from mantle-derived melts and/or fluids induced by craton destruction. The gold deposits were primarily controlled by NE-NNEtrending faults, mainly classified as fracture-controlled altered rock-type and sulfide-bearing quartz vein-type. Moreover, our study predicts that the Yalu River fault zone and its related secondary faults, as well as the periphery and deeper parts of known goldfields, are the important regions for future gold resource exploration. The Yalu River metallogenic belt has an enormous potential for gold resources, and the liaodong Peninsula has a potential to add thousands of tons of gold resources.

关键词： liaodong Peninsula Gold deposit Integrated geophysical exploration Prospecting potential Direction for prospecting breakthroughs

A Local-Global Attention Fusion Framework With Tensor Decomposition for Medical Diagnosis

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1536-1538页

作者： Peishu Wu Han li liwei hu Jirong Ge Nianyin zeng Department of Instrumental and Electrical Engineering Xiamen UniversityFujian 361005China Key Research Laboratory of Osteoporosis Syndrome Genomics Fujian Academy of Chinese Medical SciencesFuzhou 350003China

Dear Editor,In this letter,a novel hierarchical fusion framework is proposed to address the imperfect data property in complex medical image analysis(MIA)*** particular,by combining the strengths of convolutional neural networks(CNNs)and transformers,the enhanced feature extraction,spatial modeling,and sequential context learning are realized to provide comprehensive insights on the complex data *** of information in different level is enabled via a multi-attention fusion mechanism,and the tensor decomposition methods are adopted so that compact and distinctive representation of the underlying and high-dimensional medical image features can be accomplished[1].It is shown from the evaluation results that the proposed framework is competitive and superior as compared with some other advanced algorithms,which effectively handles the imperfect property of inter-class similarity and intra-class differences in diseases,and meanwhile,the model complexity is reduced within an acceptable level,which benefits the deployment in clinic *** has assumed a pivotal role in numerous critical clinical scenarios,where sophisticated image analysis techniques have proven instrumental in augmenting medical decision-making,facilitating individualized therapeutic interventions,and enhancing patient prognostication[2]−[4].

关键词： handle image property

Enhancement of low-temperature toughness of Fe-Mn-C-Al alloy by rare earth Ce-modified inclusions

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Journal of Iron and Steel Research International 2024年第1期31卷 157-173页

作者： guang-kai Yang Chang-ling Zhuang Yi-zhuang li Chen hu Shao-bo li College of Materials and Metallurgy Guizhou UniversityGuiyang550025GuizhouChina Department of Mechanical Engineering University of Hong KongHong Kong999077China The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Public Big data Guizhou UniversityGuiyang550025GuizhouChina

Fe-Mn-C-Al alloys have been recognized as promising materials for certain low-temperature applications due to their exceptional mechanical properties and ***,their limited low-temperature toughness restricts their large-scale applications in specific *** influence of trace amounts of rare earth cerium(Ce)on the low-temperature toughness of Fe-18Mn-0.6C-1.8Al alloys was *** addition of Ce effectively alters the inclu-sions in the alloy,transforming large-sized irregular inclusions into fine ellipsoidal rare earth *** leads to a significant reduction in both the proportion and average size of the inclusions,resulting in their effective dispersion throughout the matrix and improved cryogenic *** presence of Ce-containing inclusions within the matrix reduces stress concentration,thereby inhibiting microcrack formation and improving impact absorption ***-cally,the addition of rare earth Ce alters the fracture behavior of the material at room temperature and low temperature,changing from brittle cleavage fracture to a more ductile failure *** impact toughness of the Fe-Mn-C-Al alloy is significantly improved by the addition of 0.0048 wt.%Ce,particularly at-196℃where the impact toughness reaches 103.6 J/cm^(2),representing an impressive improvement of 87.3%.

关键词： Fe-Mn-C-Al alloy Rare earth Low-temperature toughness Inclusion Fracture

A social computing method for energy safety

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Journal of Safety Science and Resilience 2024年第1期5卷 64-82页

作者： Pengfei Zhao Shuangqi li Zhidong Cao Paul Jen-Hwa hu daniel dajun zeng da Xie Yichen Shen Jiangfeng li Tianyi Luo Institute of Automation Chinese Academy of SciencesUniversity of Chinese Academy of SciencesBeijing 100090China Systems Engineering Cornell UniversityIthacaNY 14853USA david Eccles School of Business the University of UtahUtahUSA Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China China University of Mining and Technology China

Information and communication technologies enable the transformation of traditional energy systems into cyber-physical energy systems(CPESs),but such systems have also become popular targets of ***,available methods for evaluating the impacts of cyberattacks suffer from limited resilience,efficacy,and practical *** mitigate their potentially disastrous consequences,this study suggests a two-stage,discrepancy-based optimization approach that considers both preparatory actions and response measures,integrating concepts from social *** proposed Kullback-Leibler divergence-based,distributionally robust optimization(KDR)method has a hierarchical,two-stage objective function that incorporates the operating costs of both system infrastructures(e.g.,energy resources,reserve capacity)and real-time response measures(e.g.,load shedding,demand-side management,electric vehicle charging station management).By incorporating social computing principles,the optimization framework can also capture the social behavior and interactions of energy consumers in response to *** preparatory stage entails day-ahead operational decisions,leveraging insights from social computing to model and predict the behaviors of individuals and communities affected by potential *** mitigation stage generates responses designed to contain the consequences of the attack by directing and optimizing energy use from the demand side,taking into account the social context and preferences of energy consumers,to ensure resilient,economically efficient CPES *** method can determine optimal schemes in both stages,accounting for the social dimensions of the *** original disaster mitigation model uses an abstract formulation to develop a risk-neutral model that characterizes cyberattacks through KDR,incorporating social computing techniques to enhance the understanding and response to cyber *** approach can mitigate the impacts more

关键词： Cyberattacks Cyber-physical energy systems Distributionally robust optimization False data injections Two-stage modeling Social computing

Comparative study on interaction between rare earth oxide refractories and rare earth treated steel

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Journal of Iron and Steel Research International 2024年第6期31卷 1493-1501页

作者： Ze Meng guang-qiang li Cheng Yuan Yi-jiang Zhao Qing Zheng Bin zeng Yu liu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan430081HubeiChina hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan430081HubeiChina Technical Center Lianyuan Iron and Steel Co.Ltd.Loudi417009HunanChina

Refractories have an important effect on the cleanliness of molten *** interaction between CeAlO_(3) refractories and Ce treated steel was explored and compared with that between Al_(2)O_(3) refractories and Ce treated *** results show that the Ce content in steel decreases sharply after contact with Al_(2)O_(3) refractories and the pick-up of dissolved Al *** with the test of Al_(2)O_(3) refractories,the loss of Ce content is less in the test of CeAlO_(3) refractory,and the total oxygen content and dissolved Al content in steel increase *** dense and continuous Ce_(2)O_(2)S interface layer is observed at the CeAlO_(3) refractories/steel interface,which can serve as the metallurgical isolation layer and hinder the further interaction between refractories and ***,the higher steel cleanliness and less penetration of refractories by molten steel are obtained in the test of CeAlO_(3) *** CeAlO_(3) refractories show a promising prospect in the production of clean Ce treated steel.

关键词： CeAlO_(3)refractory Steel Cleanliness Interaction Rare earth

Cationic surface polarization centers on ionic carbon nitride for efficient solar-driven H_(2)O_(2) production and pollutant abatement

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Chinese Chemical Letters 2024年第10期35卷 383-388页

作者： Zhenyu hu Zhenchun Yang Shiqi zeng Kun Wang lina li Chun hu Yubao Zhao MOE Key Laboratory for Water Quality and Conservation of the Pearl River Delta Institute of Environmental Research at Greater BayGuangzhou UniversityGuangzhou510006China

Solar-driven H_(2)O_(2)production and emerging organic pollutants(EOPs)elimination are of great significance from the perspective of environmental *** efficiency of the photocatalytic reaction system is the key challenge to be *** this work,the strategy of constructing surface ionic local polarization centers to enhance the exciton dissociation of the polymeric photocatalytic is *** bipyridinium cation(TMAP)is complexed on a K^(+)-incorporated carbon nitride(CNK)framework,and the combination of local polarization centers both on the surface(bipyridinium cation)and bulk(K+cation)contributes to a superior photocatalytic H_(2)O_(2)production performance,affording a remarkable H_(2)O_(2)generation rate of 46.8μmol h^(-1)mg^(-1)and a high apparent quantum yield(AQY)value of 77.5%under irradiation of 405 nm *** substantiated experimentally by steady state/transient spectroscopy techniques,the surface local polarization centers increase the population of the long-lived trapped electrons,and thereby promote the interfacial charge transfer process for chemical conversion *** strategy is potentially applicable to the design of a wide range of efficient solar-to-chemical conversion systems.

关键词： Local polarization Oxygen reductionreaction Hydrogen peroxide production Pollutantdegradation Polymeric carbon nitride