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基于组合权重-理想点法的超声滚挤压轴承套圈表层性能多目标决策

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塑性工程学报 2025年第1期32卷 76-83页

作者：刘玲玲付浩然郑州财经学院智能工程学院河南郑州450000 郑州市智能装配制造与物流优化重点实验室河南郑州450000 河南科技大学机电工程学院河南洛阳471003

为提高轴承套圈表面质量,获得较优的超声滚挤压轴承套圈表层性能(表面粗糙度、残余压应力和加工硬度)加工参数(转速、进给速度、振幅和静压力),以42CrMo为研究对象开展正交试验研究。依据层次分析法与熵权法对指标权重的确立方法进行组... 详细信息

为提高轴承套圈表面质量,获得较优的超声滚挤压轴承套圈表层性能(表面粗糙度、残余压应力和加工硬度)加工参数(转速、进给速度、振幅和静压力),以42CrMo为研究对象开展正交试验研究。依据层次分析法与熵权法对指标权重的确立方法进行组合赋权,分析轴承套圈表层性能各指标的重要影响程度。利用组合权重理想点法设定表层性能的正负理想序列,结合多目标的欧氏距离法计算超声滚挤压试验次序的接近度,决策出最优加工参数组合。结果表明:组合赋权求得表面粗糙度权重为0.536,残余压应力权重为0.238,加工硬度权重为0.226;各指标的重要影响程度为:表面粗糙度>残余压应力>加工硬度;根据组合权重理想点法决策出最优加工参数组合转速为180 r·min^(-1),进给速度为55 mm·min^(-1),振幅为25μm,静压力为600 N,进一步使得轴承套圈表层综合性能最优。

关键词：表面质量超声滚挤压组合权重欧氏距离法接近度

生物油/预处理废旧聚乙烯复合改性沥青及其混合料性能研究

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化工新型材料 2025年第2期53卷 276-281页

作者：冯新军周瀚贤傅豪长沙理工大学交通运输工程学院长沙410114

为改善废旧聚乙烯(PE)改性沥青的储存稳定性和低温性能,采用双螺杆挤出机对废旧PE进行预处理,将其与生物油复合制备了生物油/预处理废旧PE复合改性沥青。通过正交试验优选出生物油/预处理废旧PE复合改性沥青的最佳制备工艺;通过离析试... 详细信息

为改善废旧聚乙烯(PE)改性沥青的储存稳定性和低温性能,采用双螺杆挤出机对废旧PE进行预处理,将其与生物油复合制备了生物油/预处理废旧PE复合改性沥青。通过正交试验优选出生物油/预处理废旧PE复合改性沥青的最佳制备工艺;通过离析试验和流变性能试验研究复合改性沥青的路用性能;通过车辙试验、低温弯曲梁试验、浸水马歇尔试验和冻融劈裂试验研究了复合改性沥青混合料的路用性能。结果表明:与未处理废旧PE改性沥青相比,预处理废旧PE改性沥青具有更好的储存稳定性且加入生物油后,复合改性沥青的储存稳定性得到进一步改善;添加预处理废旧PE和生物油会降低复合改性沥青的高温性能,但能显著提高其低温性能;预处理废旧PE能够提高沥青混合料的高温稳定性和水稳定性,但会降低其低温抗裂性能,与生物油复合后沥青混合料的高温性能与水稳定性均会出现不同程度的降低,而低温抗裂性能提升明显且均优于基质沥青混合料。

关键词：生物油预处理废旧聚乙烯储存稳定性低温抗裂性路用性能

Global landscape of hepatic organoid research:A bibliometric and visual study

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World Journal of Hepatology 2025年第2期17卷 225-237页

作者： Tao Li Rong-Qiang Bo Jun Yan Nadia L Johnson Meng-Ting Liao Yuan Li Yan Chen Jie Lin Jian Li fu-hao Chu Xia Ding School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing 100700China Dongzhimen Hospital Beijing University of Chinese MedicineBeijing 100700China Department of Histology and Embryology School of Traditional Chinese MedicineBeijing University of Chinese MedicineBeijing 102488China Institute of Regulatory Science for Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing 100029China

BACKGROUND Hepatic organoid-based modelling,through the elucidation of a range of in vivo biological processes and the recreation of the intricate liver microenvironment,is yielding groundbreaking insights into the pathophysiology and personalized medicine approaches for liver *** This study was designed to analyse the global scientific output of hepatic organoid research and assess current achievements and future trends through bibliometric *** Articles were retrieved from the Web of Science Core Collection,and CiteSpace 6.3.R1 was employed to analyse the literature,including outputs,journals,and countries,among *** Between 2010 and 2024,a total of 991 articles pertaining to hepatic organoid research were *** journal Hepatology published the greatest number of papers,and journals with an impact factor greater than 10 constituted 60%of the top 10 *** United States and Utrecht University were identified as the most prolific country and institution,*** H emerged as the most prolific author,whereas Huch M had the highest number of cocitations,suggesting that both are ideal candidates for academic *** on hepatic organoids has exhibited a progressive shift in focus,evolving from initial investigations into model building,differentiation research in stem cells,bile ducts,and progenitor cells,to a broader spectrum encompassing lipid metabolism,single-cell RNA sequencing,and therapeutic *** phrases exhibiting citation bursts from 2022 to 2024 include“drug resistance”,“disease model”,and“patient-derived tumor organoids”.CONCLUSION Research on hepatic organoids has increased over the past decade and is expected to continue to *** research areas include applications for liver diseases and drug *** trends likely to gain focus include patient-derived tumour organoids,disease modelling,and personalized medicine.

关键词： Hepatic organoid Bibliometric analysis CiteSpace Web of Science Core Collection Three-dimensional culture

Symmetry theories of Hamiltonian systems with fractional derivatives

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Science China(Physics,Mechanics & Astronomy) 2011年第10期54卷 1847-1853页

作者： ZHOU Sha fu hao fu JingLi Institute of Mathematical Physics Zhejiang Sci-Tech University Hangzhou 310018 China China Jingye Engineering Corporation Limited Shenzhen Branch Shenzhen 518054 China

The Noether and Lie symmetries as well as the conserved quantities of Hamiltonian system with fractional derivatives are es-tablished. The definitions and criteria for the fractional symmetrical transformations and quasi-symmetrical transformations inthe Noether sense of Hamiltonian system are first discussed. Then, using the invariance of Hamiltonian action under the infini-tesimal transformations with respect to time, generalized coordinates and generalized momentums, the fractional Noethertheorem of the system is obtained. further, the Lie symmetry and conserved quantity of the system are acquired. Two exam-ples are presented to illustrate the application of the results.

关键词： symmetry conserved quantity Hamiltonian system fractional derivative

Influence of sub boundary layer vortex generator height and attack angle on cross-flows in the hub region of compressors

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Chinese Journal of Aeronautics 2022年第8期35卷 30-44页

作者： hao fu Ling ZHOU Lucheng JI School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Institute for Aero Engine Tsinghua UniversityBeijing 100084China

It has been recently shown that Sub Boundary layer Vortex Generator(SBVG,abbreviated as VG hereafter)can suppress the Cross-Flow(CF),and therefore,can eliminate corner separation and increase aerodynamic loading when installed on the end wall inside middle-load compressor ***,when VGs are applied in high-load compressors,it is difficult to achieve ideal *** is because the definition of the VG attack angle in the presence of CF in existing research is confusing,and the stronger CF in high-load compressors worsens the problem and results in an improper design and optimization range of VG attack ***,this paper clarifies the definition of the VG attack angle in the presence of CF and reveals the CF controlling mechanism of VG on a flat *** differences in the flow phenomena around a VG both with and without CF are also *** numerical results show that a larger height or attack angle of the VG generates a greater CF suppression ***,the cross velocity increases when surmounting the primary vortex induced by the VG,except that this enhanced CF is less conspicuous for larger VG *** to the cases without CF,the VG suffers an additional loss because of the stronger separation and primary vortex loss caused by the CF.

关键词： Compressors Corner separation Cross-flow Flat plate Vortex generator

Coherent quantum transport in normal-metal/d-wave superconductor/normal-metal double tunnel junctions

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Science China(Physics,Mechanics & Astronomy) 2004年第2期47卷 256-264页

作者： DONG Zhengchao fu hao Department of Physics Huaiyin Teachers College Huaiyin 223001 China Department of Physics Huaiyin Teachers College Huaiyin 223001 China

Taking into account the effects of quantum interference and interface scattering, combining the electron current with hole current contribution to tunnel current, we study the coherent quantum transport in normal-metal/d-wave superconductor/ normal-metal (NM/d-wave SC/NM) double tunnel junctions by using extended Blonder-Tinkham-Klapwijk (BTK) approach. It is shown that all quasiparticle transport coefficients and conductance spectrum exhibit oscillating behavior with the energy, in which periodic vanishing of Andreev reflection (AR) above superconducting gap is found. In tunnel limit for the interface scattering strength taken very large, there are a series of bound states of quasiparticles formed in SC.

关键词： effects of quantum interference, tunneling spectroscopy, bound state.

A Line Search SQP-type Method with Bi-object Strategy for Nonlinear Semidefinite Programming

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Acta Mathematicae Applicatae Sinica 2022年第2期38卷 388-409页

作者： Wen-hao fu Zhong-wen CHEN School of Mathematical Sciences Suzhou University of Science and TechnologySuzhou 215009China School of Mathematical Sciences Soochow UniversitySuzhou 215006China

We propose a line search exact penalty method with bi-object strategy for nonlinear semidefinite *** each iteration,we solve a linear semidefinite programming to test whether the linearized constraints are consistent or *** search direction is generated by a piecewise quadratic-linear model of the exact penalty *** penalty parameter is only related to the information of the current iterate *** line search strategy is a penalty-free *** and local convergence are analyzed under suitable *** finally report some numerical experiments to illustrate the behavior of the algorithm on various degeneracy situations.

关键词： nonlinear semidefinite programming bi-object strategy global convergence rate of convergence

Estimations of Bounds on the Multiplicative Fractional Integral Inequalities Having Exponential Kernels

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Communications in Mathematics and Statistics 2024年第2期12卷 187-211页

作者： Yu Peng hao fu Tingsong Du Department of Mathematics College of ScienceChina Three Gorges UniversityYichang 443002People’s Republic of China Three Gorges Mathematical Research Center China Three Gorges UniversityYichang 443002People’s Republic of China

To investigate the fractional Hermite–Hadamard-type inequalities,a class of the multiplicative fractional integrals having exponential kernels is *** estimations of upper bounds for the newly introduced class of integral operators are obtained in terms of the established∗differentiable *** our results presented in this study are substantial generalizations of previousﬁndings given by Ali et al.(Asian Res J Math 12:1–11,2019).Three examples are also provided to identify the correctness of the results that occur with the change of the parameter α.

关键词： Hermite–Hadamard-type inequalities Multiplicative fractional integrals Multiplicatively convex functions Differentiable functions

Design and Operational Strategy Research for Temperature Control Systems of Isothermal Compressed Air Energy Storage Power Plants

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Journal of Thermal Science 2019年第2期28卷 204-217页

作者： fu hao JIANG Tong CUI Yan LI Bin School of Electrical and Electronic Engineering North China Electric Power University

Energy storage technology is critical for intelligent power grids. It has great significance for the large-scale integration of new energy sources into the power grid and the transition of the energy structure. Based on the existing technology of isothermal compressed air energy storage, this paper presents a design scheme of isothermal compressed air energy storage power station, which uses liquid to compress air, hydraulic piston to transfer potential energy, hydraulic turbine to generate electricity at constant pressure, and liquid occupancy to store the gas at constant pressure. Then the technical features and control strategies of its internal temperature control subsystem are studied, and the mathematical model is constructed. A hierarchical relay operation is put forward to address the actual construction and operational requirements of compressed air energy storage power plants. Finally, through physical platform experiments and MATLAB simulation, the feasibility of the design is validated.

关键词： hierarchical relay operation isothermal compression compressed air energy storage power plant energy storage