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基于仿真方法的共享换电站价值量化分析

北京工业大学学报 2025年第1期51卷 22-31页

作者：沙玲汪静张海峰王岱上海工程技术大学机械与汽车工程学院上海201620 上海蔚来汽车有限公司上海201800

相较于电动汽车充电站,换电站具有补能时间短、空间面积小等优点。多品牌电动汽车高效共享换电站,能够极大程度优化补能结构,减少资源浪费。为了量化共享换电站对电动汽车用户的价值,基于排队理论,利用蔚来汽车品牌的运行数据,搭建一个... 详细信息

相较于电动汽车充电站,换电站具有补能时间短、空间面积小等优点。多品牌电动汽车高效共享换电站,能够极大程度优化补能结构,减少资源浪费。为了量化共享换电站对电动汽车用户的价值,基于排队理论,利用蔚来汽车品牌的运行数据,搭建一个模拟用户换电行为的仿真器,通过量化用户的平均排队时间和换电站数量,评估电动汽车用户在不同电动汽车规模和换电站渗透率下的换电体验。结果表明,电动汽车品牌共享换电站资源,能够显著减少电动汽车用户的排队时间,以及将排队时间保持在期望阈值内所需的换电站数量,从而提高用户的充电体验并节省换电站建设成本。

关键词：电动汽车换电站共享排队论换电体验仿真

Plastic wrinkling model and characteristics of shear enforced Ti-alloy thin-walled tubes under combination die constraints and differential temperature fields

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Chinese Journal of Aeronautics 2016年第6期29卷 1815-1829页

作者： Yan jing Aeronautical Key Laboratory for Plastic Forming Technology Beijing 100024China Beijing Key Laboratory of Digital Plastic Forming Technology and Equipment Beijing 100024China Beijing Aeronautical Manufacturing Technology Research Institute Beijing 100024China

Plastic wrinkling predictions and shear enforced wrinkling characteristics of Ti-alloy thin-walled tubes under combination die constraints have become key problems urgently in need of solutions in order to improve forming quality in their shear bending processes under differential temperature fields. To address this, a wrinkling wave function was developed by considering their shear bend deformation characteristics. Based on this wave function and the thin shell theory, an energy prediction model for this type of wrinkling was established. This model enables consideration of the effects of shear deformation zone ranges, material parameters, loading modes, and friction coefficients between tube and dies on the minimum wrinkling energy. Tube wrinkling sensitive zones(WSZs) can be revealed by combining this wrinkling prediction model with a thermalmechanical coupled finite element model for simulating these bending processes. The reliability of this wrinkling prediction model was verified, and an investigation into the tube wrinkling characteristics was carried out based on the experimental conditions. This found that the WSZs are located on either a single side or both sides of the maximum shear stress zone. When the friction coefficients between the tube and the various dies coincide, the WSZs are located on both *** larger the value of the tube inner corner radius and/or the smaller the value of the outer cornerradius, the smaller the wrinkling probability. With an increase in the value of the moving die displacement, the wrinkling probability increases at first, and then decreases.

关键词： Combination die constraint Differential temperature field Energy method Finite element Shear bending Ti-alloy thin-walled tube Wrinkling

Effects of edge cracks on the thermomagnetic instabilities of type-Ⅱ superconducting thin films

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National Science Review 2023年第3期10卷 17-28页

作者： Ze jing Institute of Extreme Mechanics and School of Aeronautics Northwestern Polytechnical University

Thermomagnetic instability is a crucial issue for the application of *** of edge cracks on the thermomagnetic instability of superconducting thin films are systematically investigated in this *** flux avalanches in thin films are well reproduced through electrodynamics simulations,and relevant physical mechanisms are revealed from dissipative vortex dynamics *** is found that edge cracks sharply decrease the threshold field for the thermomagnetic instability of superconducting *** analysis shows that the time series of magnetization jumping displays scale-invariance and follows a power law with an exponent around *** a cracked film,flux jumps more frequently with lower amplitudes compared with its crack-less *** the crack extends,the threshold field decreases,the jumping frequency gets lower,while its magnitude gets *** the crack has extended long enough,the threshold field increases to even larger than that of the crack-less *** counterintuitive result originates from the transition of the thermomagnetic instability triggered at the crack tip to the one triggered at the center of the crack edges,which is validated by the multifractal spectrum of magnetization jumping *** addition,with the variation of crack lengths,three different modes of vortex motion are found,which explains the different flux patterns formed in the avalanche process.

关键词： superconducting thin film thermomagnetic instability flux jumps edge crack scaling law

学前教育经历对小学中低年级学生学业表现的影响——基于CFPS数据的实证研究

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北京教育学院学报 2025年第1期39卷 67-75页

作者：周玲陈静北京理工大学经济学院北京102488 青岛市西海岸新区香江路第二小学山东青岛266427

学前教育是我国国民教育体系的组成部分,是重要的社会公益事业。基于中国家庭追踪调查(CFPS)2018年数据,采用计量分析方法,探讨学前教育获得年限和学前教育获得质量(幼儿园性质)对小学中低年级学生语文、数学学业表现的影响。结果表明,... 详细信息

学前教育是我国国民教育体系的组成部分,是重要的社会公益事业。基于中国家庭追踪调查(CFPS)2018年数据,采用计量分析方法,探讨学前教育获得年限和学前教育获得质量(幼儿园性质)对小学中低年级学生语文、数学学业表现的影响。结果表明,学前教育获得年限可以预测小学中低年级学生的数学成绩,且在不同性别、年级、户口类型的学生中存在差异;学前教育获得质量对小学中低年级学生的语文、数学成绩均无显著影响。建议在确保幼儿学前教育基本获得年限的基础上,完善学前教育供给,促进家园共育,以进一步保障幼儿获得高质量的学前教育。

关键词：学前教育学业表现小学中低年级教育高质量发展

深板层角膜移植与穿透性角膜移植治疗基质角膜营养不良预后的比较

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中国组织工程研究 2025年第8期29卷 1626-1633页

作者：静如意陈颖欣曹蕾北部战区总医院辽宁省沈阳市110000

背景:基质角膜营养不良的传统手术治疗方式为穿透性角膜移植,近年来越来越多的医生开始考虑使用深板层角膜移植治疗基质角膜营养不良。目前国内对比穿透性角膜移植和深板层角膜移植治疗基质角膜营养不良的研究少有报道。目的:比较深板... 详细信息

背景:基质角膜营养不良的传统手术治疗方式为穿透性角膜移植,近年来越来越多的医生开始考虑使用深板层角膜移植治疗基质角膜营养不良。目前国内对比穿透性角膜移植和深板层角膜移植治疗基质角膜营养不良的研究少有报道。目的:比较深板层角膜移植和穿透性角膜移植治疗基质角膜营养不良的疗效。方法:选择2000年1月至2018年1月北部战区总医院收治的基质角膜营养不良患者57例(57眼),男18例,女39例,平均年龄(52.9±20.0)岁,按照手术治疗方式分为深板层角膜移植组(n=21)、穿性角膜移植组(n=36),术后随访观察最佳矫正视力、角膜内皮细胞密度、角膜植片透明度、术中及术后并发症、原病复发情况。结果与结论:①两组患者术后1,3,6,12个月的视力均高于术前(P0.05);随着术后时间的延长,两组患者角膜内皮细胞密度逐渐降低,穿透性角膜移植组患者术后6,12个月的角膜内皮细胞密度年丢失率均高于深板层角膜移植组(P0.05);②深板层角膜移植组有6例出现并发症,穿透性角膜移植组有14例出现并发症,57例患者术后12个月内均无复发,两组患者术后5年的复发率比较差异无显著性意义(P>0.05),穿透性角膜移植组和深板层角膜移植组术后5年的移植物存活率分别为83%和86%,组间比较差异无显著性意义(P>0.05);③结果表明,基质角膜营养不良的治疗可考虑使用深板层角膜移植替代一部分穿透性角膜移植。

关键词：穿透性角膜移植深板层角膜移植基质角膜营养不良最佳矫正视力角膜植片透明度角膜内皮细胞密度并发症复发

The neutrino energy loss by electron capture of nuclides ^(55)Co and ^(56)Ni in explosive stellar environments

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Research in Astronomy and Astrophysics 2013年第1期13卷 99-103页

作者： jing-jing Liu College of Science and Technology Qiongzhou University

Using the Shell-Model Monte Carlo method and the Random Phase Approximation theory, we carry out an estimation of neutrino energy loss （NEL） for 55Co and 56Ni by electron capture. We find that the NEL rates increase greatly at some typical stellar conditions, and can even exceed five orders of magnitude （e.g. T9 = 38.5, Ye = 0.42 for 56Ni）. On the other hand, the error factor C shows that the fit is fairly good for two results at higher density and lower temperature, and the max- imum error is - 1.2%. However, the maximum error is ,- 55.60% （e.g. T9 = 18.5, Ye = 0.45） at lower density and higher temperature.

关键词： physical data and processes: neutrinos nuclear reactions -- stars: super-novae -- stars: evolution

基于光谱分析的鞣花酸和尿石素A~D与HSA相互作用机理研究

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光谱学与光谱分析 2025年第1期45卷 282-290页

作者：谢星程鑫鹏张露罗晶王乐怀林文静卢菲艳涂宗财江西师范大学健康学院食品营养与健康系江西南昌330022 南昌大学食品科学与资源挖掘全国重点实验室江西南昌330047

采用光谱分析结合分子模拟技术探究了鞣花酸(EA)及其代谢产物尿石素A~D(UA~D)与人血清白蛋白(HSA)的相互作用机理,有助于解析其药理毒性和药效。研究结果表明EA和UA~D能与HSA以1∶1的摩尔比例结合并通过静态方式猝灭HSA的荧光。UA和UC与... 详细信息

采用光谱分析结合分子模拟技术探究了鞣花酸(EA)及其代谢产物尿石素A~D(UA~D)与人血清白蛋白(HSA)的相互作用机理,有助于解析其药理毒性和药效。研究结果表明EA和UA~D能与HSA以1∶1的摩尔比例结合并通过静态方式猝灭HSA的荧光。UA和UC与HSA结合是氢键和范德华力驱动的放热过程,而EA和UD与HSA结合疏水相互作用驱动的吸热过程。三维荧光图谱分析表明UC~D和EA与UA~B分别增加了HSA色氨酸和酪氨酸微环境的亲水性和疏水性。分子模拟分析结果表明,EA和UA~D与HSA的活性氨基酸残基Lys436、Asp187、Lys432、Arg485、Leu430、Leu4、Ile388、Tyr411等形成氢键,与氨基酸残基Ala191、Val456、Lys199和Trp214之间存在疏水相互作用,证明其主要通过氢键和范德华力与HSA结合,屏蔽HSA的糖基化位点,抑制其糖基化。可为EA和UA~D作为糖基化抑制剂用于治疗糖尿病并发症奠定理论基础。

关键词：人血清白蛋白糖基化相互作用机理光谱分析鞣花单宁及其代谢产物

The optical nonreciprocal response based on a four-mode optomechanical system

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Chinese Physics B 2020年第3期29卷 245-250页

作者： jing Wang College of Physics Tonghua Normal UniversityTonghua 134000China

We propose a scheme for realizing the optical nonreciprocal response based a four-mode optomechanical system,consisting of two charged mechanical modes and two linearly coupled optical modes. Two charged mechanical modes are coupled by Coulomb interaction, and two optical modes are coupled to one of mechanical modes by radiation pressure. We numerically evaluate the transmission probability of the probe field to obtain the optimum optical nonreciprocal response parameters. Also, we show that the optical nonreciprocal response is caused by the quantum interference between the optomechanical couplings and the linearly coupled interaction that breaks the time-reversal symmetry.

关键词： optical nonreciprocal response optomechanical system phase difference

Ground-state cooling based on a three-cavity optomechanical system in the unresolved-sideband regime

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Chinese Physics B 2021年第2期30卷 298-303页

作者： jing Wang College of Physics Tonghua Normal UniversityTonghua 134000China

In the unresolved sideband regime,we propose a scheme for cooling mechanical resonator close to its ground state in a three-cavity optomechanical system,where the auxiliary cavities are indirectly connected with the mechanical resonator through standard optomechanical *** standard optomechanical subsystem is driven by a strong pump laser *** the help of the auxiliary cavities,the heating process is suppressed and the cooling process of the mechanical resonator is *** importantly,the average phonon number is much less than 1 in a larger *** means that the mechanical resonator can be cooled down to its ground *** these interesting features will significantly promote the physical realization of quantum effects in multi-cavity optomechanical systems.

关键词： ground-state cooling three-cavity optomechanical system unresolved sideband regime