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Journal of Computational Mathematics 2024年第2期42卷 544-569页

作者： Changhui Yao Fengdan Zhang cheng wang School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China Department of Mathematics University of MassachusettsNorth DartmouthMA 02747USA

In this paper,we consider the Cahn-Hilliard-Hele-Shaw(CHHS)system with the dynamic boundary conditions,in which both the bulk and surface energy parts play important *** scalar auxiliary variable approach is introduced for the physical system;the mass conservation and energy dissipation is proved for the CHHS ***,a fully discrete SAV finite element scheme is proposed,with the mass conservation and energy dissipation laws established at a theoretical *** addition,the convergence analysis and error estimate is provided for the proposed SAV numerical scheme.

关键词： Cahn-Hilliard-Hele-Shaw system Dynamic boundary conditions Bulk energy and surface energy Scalar auxiliary variable formulation Energy stability Convergence analysis

Explosion damage effects of aviation kerosene storage tank under strong ignition

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Defence Technology（防务技术） 2024年第7期37卷 27-38页

作者： Shixiang Song cheng wang Boyang Qiao Gongtian Gu State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

In order to study the blast damage effects of aviation kerosene storage tanks,the out-field explosion experiments of 8 m3fixed-roof tanks were carried *** fragments,shock wave and fireball thermal radiation of the tank in the presence of bottom oil,half oil and full oil,as well as empty tank,were investigated under internal explosion by various TNT charge contents(1.8 kg,3.5 kg and 6.2 kg).The results showed that the tank roof was the only fragment produced,and the damage forms could be divided into three *** increase of TNT charge content and oil volume enlarged the deformation of the tank,while the hole ratio presented a trend of increase first and then *** H_r,maxand V_(max)values positively increased as increasing the TNT charge content and oil volume(from empty to half oil),but decreased in full *** Pmaxvalues had a progressive increase with the increment of TNT charge content,but not the case with the increase in oil *** development of fireball was divided into three stages:tank roof‘towed'flame,jet flow flame tumbling and rising,and jet flow flame *** Dmaxand Hf,maxvalues both increased as increasing TNT charge content and oil *** oscillation phenomenon of fireball temperature was observed in the cooling *** average temperature of fireball surface was positively correlated with TNT charge content,and negatively correlated with oil volumes.

关键词： Aviation kerosene Storage tank Internal explosion Shock wave Fireball

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

Cleaner production of 3.5 valent vanadium electrolyte from ammonium metavanadate by ammonia reduction-sulfuric acid dissolution method

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Tungsten 2024年第3期6卷 555-560页

作者： cheng wang Lan-Jie Li Hao Du College of Chemical Engineering University of Chinese Academy of Sciences Institute of Process Engineering National Engineering Research Center of Green Recycling for Strategic Metal Resources Chinese Academy of Sciences Hesteel Group Company Limited

The vanadium redox flow battery(VRFB) has been widely used in large-scale energy storage areas due to the advantages of long lifespan and high safety. However, the high preparation cost of vanadium electrolyte limits ... 详细信息

关键词： Ammonia

Early Cretaceous Metasomatized Lithospheric Mantle beneath the Central Jiangnan Orogen in South China:Geochemical and Sr-Nd Isotope Evidence from the Tuanshanbei Dolerite

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 602-616页

作者： wang cheng WEI Hantao LIU Qingquan YANG Zhao Guangdong Provincial Key Laboratory of Geodynamics and Geohazards School of Earth Sciences and EngineeringSun Yat-sen UniversityGuangzhou 510275China Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China Development and Research Centre China Geological SurveyBeijing 100037China School of Environmental Studies China University of GeosciencesWuhan 430074China

It is well established that Cretaceous magmatism in the South China Block(SCB)is related to the Paleo-Pacific ***,the starting time and the associated deep crust-mantle processes are still *** dike swarms carry important information on the deep earth(including mantle)geodynamics and geochemical *** the Jiangnan Orogen(South China).there is no information on whether the Mesozoic magmatic activities in this region are also directly related to the Pacific subduction or *** this study,we present detailed zircon U-Pb geochronological,wholerock element and Sr-Nd isotope data for Early Cretaceous Tuanshanbei dolerite dikes,and provide new constraints on the condition of the lithospheric mantle and mantle dynamics of the SCB during that ***-ICP-MS zircon U-Pb dating suggests that this dolerite erupted in the Early Cretaceous(~145 Ma).All samples have alkaline geochemical affinities with K_(2)O+Na_(2)O=3.11-4.04 wt%,K_(2)O/Na_(2)O=0.50-0.72,and Mg^(#)=*** are enriched in LILE but depleted in HFSE with higher initial^(87)Sr/^(86)Sr ratio(0.706896-0.714743)and lower ε_(Nd)(t)(-2.61 to-1.67).They have high Nb/U,Nb/La,La/Sm and Rb/Sr,and low La/Nb,La/Ta,Ce/Pb,Ba/Rb,Tb/Yb and Gd/Yb *** geochemical signatures suggest that the fractional crystallization is obvious but crustal contamination play a negligible role during magmatic *** dolerite were most likely derived from low-degree(2%-5%)partial melting of a phlogopite-bearing mantle material consisted of~85% spinel peridotite and~15% garnet peridotite previously metasomatized by asthenospherederived fluids/melts with minor subduction-derived fluids/***-rollback generally lead to the upwelling of the hot *** upwelling of asthenosphere consuming the lithospheric mantle by thermo-mechanical-chemical *** lithospheric mantle may have partially melted due to the heating by the upwelling asthenosphere and lithospheric extension.I

关键词： Early Cretaceous mafic dike metasomatized lithospheric mantle Tuanshanbei dolerite Jiangnan Orogen South China

Strategic Contracting for Software Upgrade Outsourcing in Industry 4.0

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1563-1592页

作者： cheng wang Zhuowei Zheng College of Mechanical Engineering Zhejiang University of TechnologyHangzhou310014China Taizhou Research Institute Zhejiang University of TechnologyTaizhou318001China

The advent of Industry 4.0 has compelled businesses to adopt digital approaches that combine software toenhance production efficiency. In this rapidly evolving market, software development is an ongoing process thatmust be tailored to meet the dynamic needs of enterprises. However, internal research and development can beprohibitively expensive, driving many enterprises to outsource software development and upgrades to externalservice providers. This paper presents a software upgrade outsourcing model for enterprises and service providersthat accounts for the impact of market fluctuations on software adaptability. To mitigate the risk of adverseselection due to asymmetric information about the service provider’s cost and asymmetric information aboutthe enterprise’s revenues, we propose pay-per-time and revenue-sharing contracts in two distinct informationasymmetry scenarios. These two contracts specify the time and transfer payments for software upgrades. Througha comparative analysis of the optimal solutions under the two contracts and centralized decision-making withfull-information, we examine the characteristics of the solutions under two information asymmetry scenarios andanalyze the incentive effects of the two contracts on the various stakeholders. Overall, our study offers valuableinsights for firms seeking to optimize their outsourcing strategies and maximize their returns on investment insoftware upgrades.

关键词： Software upgrade outsourcing the principal-agent information asymmetry reverse selection contract design

Experimental investigation on weak shock wave mitigation characteristics of flexible polyurethane foam and polyurea

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Defence Technology（防务技术） 2024年第1期31卷 179-191页

作者： Shiyu Jia cheng wang Wenlong Xu Dong Ma Fangfang Qi State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Institute for Advanced Technology Shandong UniversityJinan250061China

In recent years,explosion shock wave has been considered as a signature injury of the current military *** strong shock wave is lethal to the human body,weak shock wave can cause many more lasting *** investigate the protection ability and characteristics of flexible materials and structures under weak shock wave loading,the blast wave produced by TNT explosive is loaded on the polyurethane foam with the density of 200.0 kg/m3(F-200)and 400.0 kg/m3(F-400),polyurea with the density of 1100.0 kg/m^(3)(P-1100)and structures composed of the two materials,which are intended for individual *** results indicate that the shock wave is attenuated to weak pressure disturbance after interacting with the flexible materials which are not *** shock wave protective capability of single-layer materials is dependent on their thickness,density and microscopic *** overpressure,maximum pressure rise rate and impulse of transmitted wave decrease exponentially with increase in sample *** the same thickness,F-400 provides better protective capability than F-200 while P-1100 shows the best protective capability among the three *** this study,as the materials are not destroyed,F-200 with a thickness more than10.0 mm,F-400 with a thickness more than 4.0 mm,and P-1100 with a thickness more than 1.0 mm can attenuate the overpressure amplitude more than 90.0%.Further,multi-layer flexible composites are *** layer layouts of designed structures and layer thickness of the single-layer materials can affect the protective *** the research range,the structure in which polyurea is placed on the impact side shows the optimal shock wave protective performance,and the thicknesses of polyurea and polyurethane foam are 1.0 mm and 4.0 mm *** overpressure attenuation rate reached maximum value of 93.3%and impulse attenuation capacity of this structure are better than those of s

关键词： Free-field explosion Weak shock wave mitigation Polyurea Polyurethane foam Multi-layered composites

Propagation Properties of Shock Waves in Polyurethane Foam based on Atomistic Simulations

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Defence Technology（防务技术） 2024年第1期31卷 117-129页

作者： Zhiqiang Hu Jianli Shao Shiyu Jia Weidong Song cheng wang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

Porous materials are widely used in the field of protection because of their excellent energy absorption *** this work,a series of polyurethane microscopic models are established and the effect of porosity on the shock waves is studied with classical molecular dynamics ***,shock Hugoniot relations for different porosities are obtained,which compare well with the experimental *** pores collapse and form local stress wave,which results in the complex multi-wave structure of the shock *** microstructure analysis shows that the local stress increases and the local velocity decreases gradually during the process of pore collapse to complete ***,it leads to stress relaxation and velocity *** shock stress peaks can be fitted with two exponential functions,and the amplitude of attenuation coefficient decreases with the increase of ***,the pore collapse under shock or non-shock are discussed by the entropy increase rate of the *** energy is dissipated mainly through the multiple interactions of the waves under *** energy is dissipated mainly by the friction between atoms under non-shock.

关键词： Polyurethane foam Shock wave Attenuation Atomistic simulation

Convergence analysis for complementary-label learning with kernel ridge regression

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 533-544页

作者： NIE Wei-lin wang cheng XIE Zhong-hua School of Mathematics and Statistics Huizhou UniversityHuizhou 516007China School of Computer Science and Engineering Huizhou UniversityHuizhou 516007China

Complementary-label learning(CLL)aims at finding a classifier via samples with complementary *** data is considered to contain less information than ordinary-label *** transition matrix between the true label and the complementary label,and some loss functions have been developed to handle this *** this paper,we show that CLL can be transformed into ordinary classification under some mild conditions,which indicates that the complementary labels can supply enough information in most *** an example,an extensive misclassification error analysis was performed for the Kernel Ridge Regression(KRR)method applied to multiple complementary-label learning(MCLL),which demonstrates its superior performance compared to existing approaches.

关键词： multiple complementary-label learning partial label learning error analysis reproducing kernel Hilbert spaces

Multimodal Machine Learning Guides Low Carbon Aeration Strategies in Urban Wastewater Treatment

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Engineering 2024年第5期36卷 51-62页

作者： Hong-cheng wang Yu-Qi wang Xu wang Wan-Xin Yin Ting-Chao Yu Chen-Hao Xue Ai-Jie wang State Key Laboratory of Urban Water Resource and Environment School of Civil and Environmental EngineeringHarbin Institute of Technology(Shenzhen)Shenzhen 518055China Key Laboratory of Drinking Water Safety and Distribution Technology of Zhejiang Province College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou 310058China

The potential for reducing greenhouse gas(GHG)emissions and energy consumption in wastewater treatment can be realized through intelligent control,with machine learning(ML)and multimodality emerging as a promising ***,we introduce an ML technique based on multimodal strategies,focusing specifically on intelligent aeration control in wastewater treatment plants(WWTPs).The generalization of the multimodal strategy is demonstrated on eight ML *** results demonstrate that this multimodal strategy significantly enhances model indicators for ML in environmental science and the efficiency of aeration control,exhibiting exceptional performance and *** random forest with visual models achieves the highest accuracy in forecasting aeration quantity in multimodal models,with a mean absolute percentage error of 4.4%and a coefficient of determination of *** testing in a full-scale plant reveals that the multimodal model can reduce operation costs by 19.8%compared to traditional fuzzy control *** potential application of these strategies in critical water science domains is *** foster accessibility and promote widespread adoption,the multimodal ML models are freely available on GitHub,thereby eliminating technical barriers and encouraging the application of artificial intelligence in urban wastewater treatment.

关键词： Wastewater treatment Multimodal machine learning Deep learning Aeration control Interpretable machine learning