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基于可拓云耦合模型的本科生科研创新能力系统研究——以矿业高校为例

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系统科学学报 2021年第1期29卷 98-103页

作者：薛黎明王恩郑志学朱琳龙李长明中国矿业大学(北京)能源与矿业学院北京100083 北京大学工学院北京100871

为分析评价我国矿业类高校本科生科研创新能力,以具有代表性的四所矿业高校为例,综合分析影响科研创新能力的因素,选取学习兴趣、专业实习经历、科研经费投入等18个指标构建指标体系;为了克服评价系统不相容性和指标分级模糊性对结果的... 详细信息

为分析评价我国矿业类高校本科生科研创新能力,以具有代表性的四所矿业高校为例,综合分析影响科研创新能力的因素,选取学习兴趣、专业实习经历、科研经费投入等18个指标构建指标体系;为了克服评价系统不相容性和指标分级模糊性对结果的影响,构建可拓云耦合评价模型,通过单指标云关联度与改进AHP权重计算综合云关联度,结合等级云图分析确定本科生科研创新能力所属等级。结果表明:四所高校本科生的科研创新能力整体上处于中等偏上水平,但在论文、专利、实习经历等方面相对薄弱,与我国高校实际情况相吻合,为高校本科生科研创新能力评价提供了一种新方法。

关键词：系统研究矿业高校本科生科研创新能力可拓云耦合模型

Suppression of stimulated Brillouin and Raman scatterings using an alternating frequency laser and transverse magnetic fields

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Chinese Physics B 2024年第1期33卷 545-553页

作者：程瑞锦李晓旬王清刘德基黄卓明吕帅宇周远志张舒童李雪铭陈祖杰王强刘占军曹莉华郑春阳 Institute of Applied Physics and Computational Mathematics Beijing 100094China HEDPS Center for Applied Physics and Technologyand State Key Laboratory of Nuclear Physics and TechnologySchool of PhysicsPeking UniversityBeijing 100871China HEDPS Center for Applied Physics and Technologyand College of EngineeringPeking UniversityBeijing 100871China

A novel scheme to suppress both stimulated Brillouin scattering(SBS) and stimulated Raman scattering(SRS) by combining an alternating frequency(AF) laser and a transverse magnetic field is proposed. The AF laser allows the laser frequency to change discretely and alternately over time. The suppression of SBS is significant as long as the AF difference is greater than the linear growth rate of SBS or the alternating time of the laser frequency is shorter than the linear growth time of SBS. However, the AF laser proves ineffective in suppressing SRS, which usually has a much higher linear growth rate than SBS. To remedy that, a transverse magnetic field is included to suppress the SRS instability. The electrons trapped in the electron plasma waves(EPWs) of SRS can be accelerated by the surfatron mechanism in a transverse magnetic field and eventually detrapped. While continuously extracting energy from EPWs, the EPWs are dissipated and the kinetic inflation of SRS is suppressed. The one-dimensional particle-in-cell simulation results show that both SBS and SRS can be effectively suppressed by combining the AF laser with a transverse magnetic field with tens of Tesla. The total reflectivity can be dramatically reduced by more than one order of magnitude. These results provide a potential reference for controlling SBS and SRS under the related parameters of inertial confinement fusion.

关键词： stimulated Brillouin scattering stimulated Raman scattering alternating frequency laser transverse magnetic field

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300米以下超高层建筑消防问题讨论

给水排水 2017年第1期43卷 107-115页

作者：薛学斌李鸣杨俊晨程磊中衡设计集团股份有限公司苏州215000

简要介绍了300m以下超高层建筑消防系统的几种典型供水方式;立足于系统关键环节,对各系统的供水安全性作详细计算和探讨;纠正了常规认识中对水泵直接串联系统安全性的偏见;同时对超高层建筑群的消防设计提出建议;结合新版消防规范,对超... 详细信息

简要介绍了300m以下超高层建筑消防系统的几种典型供水方式;立足于系统关键环节,对各系统的供水安全性作详细计算和探讨;纠正了常规认识中对水泵直接串联系统安全性的偏见;同时对超高层建筑群的消防设计提出建议;结合新版消防规范,对超高层建筑消防分区提出划分建议;对最不利消火栓栓口动压提出修改建议;对消防主材与系统压力的关系做进一步探讨,提出选型要求。

关键词：超高层建筑消防系统关键环节系统安全性消防水泵直接串联中间水箱转输串联供水系统工作压力一泵到顶系统

网络金融犯罪的刑法介入限度及路径选择——以非法吸收公众存款罪为例

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广西政法管理干部学院学报 2024年第3期39卷 123-128页

作者：薛力铭北京师范大学法学院北京100875

网络金融与传统金融相比,在降低融资门槛,优化资金服务上具有无可比拟的优势。但是,频发的网络金融犯罪,对金融市场秩序造成了严重的影响。刑法作为介入社会治理的“双刃剑”,在为金融市场的良性发展保驾护航的同时,过度介入网络金融领... 详细信息

网络金融与传统金融相比,在降低融资门槛,优化资金服务上具有无可比拟的优势。但是,频发的网络金融犯罪,对金融市场秩序造成了严重的影响。刑法作为介入社会治理的“双刃剑”,在为金融市场的良性发展保驾护航的同时,过度介入网络金融领域,也会阻碍金融创新。因此,在刑法的介入时机上,需要在保障金融创新的前提下,通过加强行政监管,避免刑法介入过度前置;在刑法的介入限度上,应当结合法益保护原则以及实质违法性的判断,明确相关犯罪的入罪门槛,避免形式认定带来的弊端,以实现对网络金融犯罪的合理规制。

关键词：网络金融金融犯罪刑法介入非法吸收公众存款罪

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng Gao Yu-Gui Peng Peng Wu Zong-lin li xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie li Wenbo Yu Zhenyu Sun Weichen Zheng liangwei Zhang Yanling xue Wenning liu Shoumei Xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

基于FP-tree与云变换的围岩稳定性评价指标体系研究

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铁道标准设计 2019年第7期63卷 102-107页

作者：薛黎明李长明郑志学孟硕王恩王豪杰中国矿业大学(北京)资源与安全工程学院北京100083 北京大学工学院北京100871

针对围岩稳定性指标体系暂无统一的标准,且现阶段地下工程呈现大型化和密集化的趋势,所以现有的围岩稳定性体系难以适用于围岩准确分级。对此,将现有的分级标准及文献中分级体系进行汇总建立指标数据库,通过FP-tree进行关联挖掘得到围... 详细信息

针对围岩稳定性指标体系暂无统一的标准,且现阶段地下工程呈现大型化和密集化的趋势,所以现有的围岩稳定性体系难以适用于围岩准确分级。对此,将现有的分级标准及文献中分级体系进行汇总建立指标数据库,通过FP-tree进行关联挖掘得到围岩稳定性的分级指标,并采用变异系数法验证体系的稳定性。运用云变换得到该体系中各指标的等级云图,对各指标进行分级,实现等级的软划分,考虑等级阈值的模糊性,使分级标准更符合思维逻辑和工程实际。将该体系应用于工程实际中,评价结果与工程实际相吻合,证明该体系的科学性与合理性,为围岩稳定性评价提供一套简洁适用的体系,为构建评价指标体系提供一种科学合理的方法。

关键词：围岩稳定性指标体系 FP-tree 云变换阈值