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Advances in Applied Mathematics and Mechanics 2024年第1期16卷 181-207页

作者： Xiaolong Zhao Xijun Yu Zupeng Jia Shijun Zou meilan qiu School of Mathematics and Statistics Zhengzhou UniversityZhengzhouHenan 450001China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China School of Mathematics and Statistics Huizhou UniversityHuizhouGuangdong 516007China Institute of Applied Physics and Computational Mathematics Beijing 100088China

In this paper,we present a new vertex-centered arbitrary LagrangianEulerian(ALE)finite volume scheme for two-dimensional compressible *** our scheme,the momentum equation is discretized on the vertex control volume,while the mass equation and the energy equation are discretized on the sub-cells which are included in the vertex control *** attain the average of the fluid velocity on the vertex control volume directly by solving the conservation *** we can obtain the fluid velocity at vertex with the reconstructed polynomial of the *** fluid velocity is chosen as the mesh velocity,which makes the mesh move in a Lagrangian *** WENO(Weighted Essentially Non-Oscillatory)reconstructions for the density(the total energy)and the velocity are used to make our scheme achieve the anticipated *** with the general vertexcentered schemes,our scheme with the new approach for the space discretization can simulate some multi-material flows which do not involve large *** addition,our scheme has good robustness,and some numerical examples are presented to demonstrate the anticipated accuracy and the good properties of our scheme.

关键词： Vertex-centered arbitrary Lagrangian-Eulerian sub-cells multi-material flows

Existence of Weak Solutions for a Class of Quasilinear Parabolic Problems in Weighted Sobolev Space

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Advances in Pure Mathematics 2013年第1期3卷 204-208页

作者： meilan qiu Liquan Mei Center for Computational Geosciences Xi’an Jiaotong University Xi’an China School of Mathematics and Statistics Xi’an Jiaotong University Xi’an China

In this paper, we investigate the existence and uniqueness of weak solutions for a new class of initial/boundary-value parabolic problems with nonlinear perturbation term in weighted Sobolev space. By building up the compact imbedding in weighted Sobolev space and extending Galerkin’s method to a new class of nonlinear problems, we drive out that there exists at least one weak solution of the nonlinear equations in the interval [0,T] for the fixed time T>0.

关键词： Weighted Sobolev Space Energy Estimates Compact Imbedding Sobolev Interpolation Inequalities

基于翻转课堂模式的护理查房在中医规培护士岗位胜任力中的应用

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新中医 2024年第14期56卷 170-173页

作者：杨丽君刘文导周春姣邓华梅廖文娟丘美兰梁好陈捷晗广州中医药大学第二附属医院广东广州510120

目的:探索基于翻转课堂模式的护理查房在提高中医规培护士岗位胜任力中的应用效果。方法:将165名外科轮科的规培期护士按照查房模式的不同分为对照组87名和改革组78名。对照组采用常规方式查房,改革组采用基于翻转课堂的中医护理查房。... 详细信息

目的:探索基于翻转课堂模式的护理查房在提高中医规培护士岗位胜任力中的应用效果。方法:将165名外科轮科的规培期护士按照查房模式的不同分为对照组87名和改革组78名。对照组采用常规方式查房,改革组采用基于翻转课堂的中医护理查房。方案实施结束后比较2组改良版中医护理迷你临床演练评估表评分,以及规培护士和指导带教老师满意度评分。结果:改良版中医护理迷你临床演练评估表及规培生满意度、带教老师满意度评分表有效回收率均为100%。改革组床边护理问诊与专科体查、健康咨询与宣教、护理诊断(问题)、护理计划与实施、中西医护理思维与方法、人文关怀、组织效能、整体胜任力等评分均高于对照组,差异有统计学意义(P0.05)。改革组规培护士、带教指导老师满意度评分均高于对照组,差异有统计学意义(P<0.05)。结论:基于翻转课堂模式的护理查房有助于提高中医规培护士的岗位胜任力和多项综合能力,并且规培护士和带教老师对此满意度更高。

关键词：中医规培护理查房翻转课堂迷你临床演练评估岗位胜任力

Challenges and prospects for room temperature solid-state sodiumsulfur batteries

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Nano Research 2024年第3期17卷 1402-1426页

作者： Yashuang qiu Jing Xu Research Center of Grid Energy Storage and Battery Application School of Electrical and Information EngineeringZhengzhou UniversityZhengzhou 450001China

Room temperature sodium-sulfur(Na-S)batteries,known for their high energy density and low cost,are one of the most promising next-generation energy storage ***,the polysulfide shuttling and uncontrollable Na dendrite growth as well as safety issues caused by the use of organic liquid electrolytes in Na-S cells,have severely hindered their ***-state electrolytes instead of liquid electrolytes are considered to be the most direct and effective solution to solve the above ***,its practical application is still greatly challenged due to the poor interfacial compatibility between the all-solid-state electrolytes and the anode/cathode,ionic conductivity,and the shuttle effect caused by the presence of liquid phase in the quasi-solid-state *** paper presents a comprehensive review of solid-state Na-S batteries from the perspective of regulating interfacial compatibility and improving ionic conductivity as well as suppressing polysulfide *** to different components,solid-state electrolytes were divided into five categories:solid inorganic electrolytes,solid polymer electrolytes,polymer/inorganic solid hybrid electrolytes,gel polymer electrolytes,and liquid–solid inorganic hybrid ***,the prospect of developing high performance solid-state electrolytes to improve the cycling stability of room temperature Na-S cells is envisaged.

关键词： sodium-sulfur batteries solid-state electrolytes ionic conductivity polysulfide shuttling interfacial compatibility

Novel rockburst prediction criterion with enhanced explainability employing CatBoost and nature-inspired metaheuristic technique

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Underground Space 2024年第6期19卷 101-118页

作者： Yingui qiu Jian Zhou School of Resources and Safety Engineering Central South UniversityChangsha 410083China

Rockburst is a major challenge to hard rock engineering at great *** and timely assessment of rockburst risk can avoid unnecessary casualties and property *** the existence of various methods for rockburst assessment,there remains an urgent need for a comprehensive and reliable criterion that is easy to both apply and *** a new rockburst criterion based on simple parameters can potentially fill this *** its advantages,this criterion can facilitate a more effective and efficient prediction of rockburst potential,thereby contributing significantly to enhancing safety *** this paper,combined with the internal and external factors of rockburst,four control variables(i.e.,integrity index,stress index,brittleness index,and elastic energy index)were selected to be incorporated into a comprehensive rockburstability index(RBSI).Based on 116 sets of rockburst cases,the rockburst potential was accurately quantified and predicted using the categorical boosting(CatBoost)model and the nature-inspired metaheuristic African vultures optimization algorithm(AVOA).In its performance validation,the criterion achieved the highest accuracy of 90.48%,verifying the reliability and effectiveness of the proposed RBSI ***,an interpretive method was applied to analyze the variable influence on the criterion,facilitating the explanation of predictions and the analysis of the formula’s robustness under different *** general,compared with existing criterion methods involving relevant indicators,the newly proposed RBSI criterion enhances the accuracy of rockburst potential prediction,and it can effectively and swiftly evaluate the preliminary risk of ***,a graphical user interface was developed to provide a clear visualization of the assessment of rockburst potential.

关键词： Rockburst criterion CatBoost Metaheuristic optimization Model interpretation Graphical user interface

Electrochemical conversion of organic compounds and inorganic small molecules

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Science China Chemistry 2024年第10期67卷 3223-3246页

作者： Weimei Zeng Youai qiu Department of Chemistry Nankai UniversityTianjin 300071China

Electrochemical synthesis presents a facile and sustainable strategy to produce valuable *** review summarizes the most recent advances in electrosynthesizing value-added compounds with inorganic small ***“small molecules”refers to a broad spectrum of chemicals,we mainly focus on the electrochemical conversion of CO_(2),H_(2)O/D_(2)O,NH_(3)and SO_(2)until March *** review intends to compare the results and display general trends throughout the field,with an emphasis on the substrate scope and mechanical ***,we propose several techniques and protocols that can enable a more fundamental understanding of the electrochemical reaction involving inorganic small molecules and help drive this methodology toward commercialization.

关键词： electrochemical synthesis inorganic small molecule organic synthesis carbon dioxide water

Enhanced service stability and thermoelectric performance in Cu_(2)−δSebased composites

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Science China Materials 2024年第7期67卷 2369-2370页

作者： Pengfei qiu Xun Shi State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China

Thermoelectric(TE)materials can directly convert the industrial waste heat into useful electricity based on the Seebeck effect,providing a promising way to tackle the environmental pollution and global energy crisis[1].In the past several decades,many new high-performance TE materials have been discovered to enrich the TE *** them,Cu_(2)−δSe-based TE materials,which are in line with the“phonon-liquid electron-crystal”concept,have sparked widespread interest due to the high TE figure-of-merit(ZT)and the combination of elements that are nontoxic and earth-abundant[2].In 2012,Liu et al.[3]reported a ZT of 1.5 at 1000 K in the stoichiometric Cu_(2)*** alloying S at the Se-site,the ZT was enhanced to around 2.0 at 1000 K[4].Via incorporating carbon nanotubes,the ZT was further enhanced to 2.4 at 1000 K[5].Moreover,Yang et al.[6]and Zhou et al.[7]reported that the ZT of Cu_(2)Se/BiCuSeO composites can reach 2.7–2.8 around 1000 K.

关键词： composites BiCuSeO performance

y-Tuning: an efficient tuning paradigm for large-scale pre-trained models via label representation learning

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Frontiers of Computer Science 2024年第4期18卷 107-116页

作者： Yitao LIU Chenxin AN Xipeng qiu School of Computer Science Fudan UniversityShanghai 200433China

With current success of large-scale pre-trained models(PTMs),how efficiently adapting PTMs to downstream tasks has attracted tremendous attention,especially for PTMs with billions of *** work focuses on designing parameter-efficient tuning paradigms but needs to save and compute the gradient of the whole computational *** this paper,we propose y-Tuning,an efficient yet effective paradigm to adapt frozen large-scale PTMs to specific downstream tasks.y-Tuning learns dense representations for labels y defined in a given task and aligns them to fixed feature *** computing the gradients of text encoder at training phrase,y-Tuning is not only parameterefficient but also *** results show that for DeBERTaxxL with 1.6 billion parameters,y-Tuning achieves performance more than 96%of full fine-tuning on GLUE Benchmark with only 2%tunable parameters and much fewer training costs.

关键词： pre-trained model lightweight fine-tuning paradigms label representation

The First Five Years of a Phase Theory for Complex Systems and Networks

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1728-1743页

作者： Dan Wang Wei Chen Li qiu Division of Decision and Control Systems KTH Royal Institute of TechnologyStockholm 10044Sweden Department of Mechanics and Engineering Science&the State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing 100871China Hong Kong University of Science and Technology Hong KongChinaand also with the Southern University of Science and TechnologyShenzhen 518055China

In this paper,we review the development of a phase theory for systems and networks in its first five years,represented by a trilogy:Matrix phases and their properties;The MIMO LTI system phase response,its physical interpretations,the small phase theorem,and the sectored real lemma;The synchronization of a multi-agent network using phase *** the end,we also summarize a list of ongoing research on the phase theory and speculate what will happen in the next five years.

关键词： Consensus and synchronization matrix phases multi-agent systems phase theory sectored real lemma small phase theorem.

Effect of Modulus Heterogeneity on the Equilibrium Shape and Stress Field ofαPrecipitate in Ti-6Al-4V

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 1017-1028页

作者： Di qiu Rongpei Shi Materials Genome Institute Shanghai UniversityShanghai200444China School of Materials Science and Engineering Harbin Institute of TechnologyShenzhen518055China Shanghai Frontier Science Center of Mechanoinformatics Shanghai UniversityShanghai200444China Zhejiang Laboratory Hangzhou311100China

For media with inclusions(e.g.,precipitates,voids,reinforcements,and others),the difference in lattice parameter and the elastic modulus between the matrix and inclusions cause stress concentration at the *** stress fields depend on the inclusions’size,shape,and distribution and will respond instantly to the evolving *** study develops a phase-field model concerningmodulus *** effect of modulus heterogeneity on the growth process and equilibrium state of theαplate in Ti-6Al-4V during precipitation is ***αprecipitate exhibits strong anisotropy in shape upon cooling due to the interplay of the elastic strain and interfacial *** calculated orientation of the habit plane using the homogeneous modulus ofαphase shows the smallest deviation fromthat of the habit plane observed in the experiment,compared to the case where the homogeneous modulus ofβphase is *** addition,the equilibrium volume ofαphase within the systemusing homogeneousβmodulus exhibits the largest dependency on the applied *** stress fields across theα/βinterface are further calculated under the assumption of modulus heterogeneity and compared to those using homogeneous modulus of eitherαorβ*** study provides an essential theoretical basis for developing mechanics models concerning systems with heterogeneous structures.

关键词： Elastic heterogeneity habit plane stress field titanium phase-field simulation