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Chinese Journal of Aeronautics 2024年第8期37卷 79-90页

作者： Shijie liU Tianyu PAN qiushi li ` School of Energy and Power Engineering Beihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China Key Laboratory of Fluid and Power Machinery Ministry of EducationXihua UniversityChengdu 610039China

Accurate prediction of the aerodynamic response of a compressor under inlet distortion is crucial for next-generation civil aircraft,such as Boundary Layer Ingestion(Bli)silent ***,research on the Body Force(BF)model plays a significant role in achieving this ***,distorted inlet airflow can lead to varying operating conditions across different spatial locations of the compressor,which may cause some regions to operate outside the stability ***,the accuracy of BF model simulations might be *** address this issue,this paper proposes a numerical simulation strategy for acquiring the steady axisymmetric three-dimensional flow field of a compressor operating at low mass flow rates,which is known as the Underlying Axisymmetric Pressure Rise Characteristic(UAPRC).The proposed simulation accounts for two different rotor speeds of a transonic compressor and identifies initial positions in the flow field where deterioration occurs based on prior experimental ***,simulation results are incorporated into the BF model to replicate hub instability observed in *** results demonstrate that this strategy provides valid predictions of the UAPRC of the compressor,thereby addressing the limitations associated with the BF model.

关键词： Compressor partial instability Performance at low mass flow rates Underlying axisymmetric pressure rise characteristic Novel simulation strategy Body force model

面向数智化转型的高校图书馆馆员数字胜任力形成路径及提升策略研究

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图书情报工作 2024年第14期68卷 45-57页

作者：李秋实李雯华中师范大学信息管理学院武汉430079 中国图书馆创新发展研究中心武汉430079

[目的/意义]面向数智化转型是数智融合发展新环境下高校图书馆的重要发展趋势,高校图书馆馆员在图书馆数智化转型中发挥主体作用,其数字胜任力是服务转型的核心业务能力,关系到数智化转型目标的实现程度。[方法/过程]面向数智化转型目标... 详细信息

[目的/意义]面向数智化转型是数智融合发展新环境下高校图书馆的重要发展趋势,高校图书馆馆员在图书馆数智化转型中发挥主体作用,其数字胜任力是服务转型的核心业务能力,关系到数智化转型目标的实现程度。[方法/过程]面向数智化转型目标,综合运用实地调研与访谈方法,掌握当前高校图书馆馆员数字胜任力现状,厘清数字胜任力内涵与维度。结合一手资料,通过扎根编码方法识别馆员数字胜任力影响因素,进一步收集问卷数据,采用模糊集定性比较方法,从系统内外多因素联动效应出发,剖析馆员数字胜任力形成的组态路径。[结果/结论]总结出价值感知型、需求导向型、社群影响型和环境支持型四条高校图书馆馆员数字胜任力形成路径,据此提出高校图书馆馆员数字胜任力提升策略。

关键词：数智化转型高校图书馆馆员数字胜任力 fsQCA

国外公共文化数字化转型：研究主题、框架与前瞻

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中国图书馆学报 2024年第03期50卷 117-129页

作者：李秋实陈一段若阳华中师范大学信息管理学院武汉大学信息管理学院

以大数据、人工智能为代表的数字化技术推动了世界范围内的公共文化数字化转型，对国外相关研究进行梳理，有助于掌握国际公共文化数字化转型发展全貌，为我国相关领域的实践和研究提供参考。本文选取新世纪以来国外公共文化数字化转型... 详细信息

以大数据、人工智能为代表的数字化技术推动了世界范围内的公共文化数字化转型，对国外相关研究进行梳理，有助于掌握国际公共文化数字化转型发展全貌，为我国相关领域的实践和研究提供参考。本文选取新世纪以来国外公共文化数字化转型研究的代表性文献，运用系统性综述方法，凝练研究热点主题，从系统论和复杂性视角构建整合性研究框架，前瞻未来研究方向。研究发现，当前研究主题主要集中在公共文化数字化转型内涵、转型前因条件、转型过程机制和转型影响成效四个方面。公共文化数字化转型具有注重用户需求、技术驱动、机构合作融合的特征；外部环境、信息技术和组织管理是转型的前因条件；通过资源融合、众包交互、合作协同的转型过程机制，公共文化机构优化用户体验，提升服务效能，增进社会福祉。在此基础上，本文进一步提出公共文化数字化转型研究的未来方向，以期为我国公共文化机构平稳转型、高质量发展提供有益参考。图1。参考文献48。

关键词：公共文化数字化转型整合性研究框架

“科教兴国”战略下生物学师范生科学探究素养的提升策略

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生物学教学 2024年第6期49卷 10-13页

作者：崔月刘婷李秋石河北师范大学教师教育学院石家庄050024

科学探究素养是生物学教师科学素养的重要组成,中学生的科学探究素养水平与教师的探究素养水平密切相关。生物学师范生是我国中学生物学教师队伍的后备力量。立足生物学教师科学素养,结合生物学学科性质,制定生物学师范生科学探究素养... 详细信息

科学探究素养是生物学教师科学素养的重要组成,中学生的科学探究素养水平与教师的探究素养水平密切相关。生物学师范生是我国中学生物学教师队伍的后备力量。立足生物学教师科学素养,结合生物学学科性质,制定生物学师范生科学探究素养提升策略,是促进生物学学科核心素养目标有效落实的重要路径。

关键词：科学探究素养科学素养生物学师范生教师教育

Effects of the radial blade loading distribution and B parameter on the type of flow instability in a low-speed axial compressor

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Chinese Journal of Aeronautics 2018年第7期31卷 1470-1479页

作者： qiushi li Simin li Tianyu PAN National Key Laboratory of Science and Technology on Aero-Engine Aerothermodynamics Collaborative Innovation Center for Advanced Aero-Engine School of Energy and Power Engineering Beihang University Department of Mechanical Engineering and Materials Science Duke University

Previous studies showed that an axisymmetric hub-initiated disturbance defined as partial surge may initiate the stall of a transonic compressor; to reveal the instability evolution under full-span incompressible flow for different levels of hub loading and B parameter, an experimental investigation is conducted on a single-stage low-speed compressor. Experimental results show that under a uniform inflow condition without inlet flow distortion, a modal-type stall inception dominates in this low-speed compressor. When an inlet screen introducing hub distortion is used to increase the hub loading, a compressor stall is initiated by a modal wave, but large disturbances are present in the hub region before the compressor stall, which become stronger as the hub loading increases. Under high hub loading and large B parameter（implemented by adding hub distortion through an inlet screen and enlarging the outlet plenum volume, respectively）, a compressor stall is triggered by an axisymmetric hub-initiated disturbance, which is much different from the modal-like disturbances. The beginning of this axisymmetric disturbance may be captured over 800 rotor revolutions prior to the onset of stall, and the amplitude grows with time. The disturbance is hub-initiated because the disturbance signal at the hub is detected much earlier than that at the tip; meanwhile, the frequency of this axisymmetric disturbance changes with the length of the inlet duct. The characteristics of instability evolution in the low-speed compressor are also compared with those in a transonic compressor.

关键词： Axisymmetric disturbance B parameter Flow instability Low-speed axial compressor Radial blade loading distribution

多源流理论视角下我国教育硕士专业学位政策演变分析

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高教论坛 2024年第4期 109-114页

作者：李秋石景达河北师范大学河北石家庄050024

对1996-2023年我国教育硕士专业学位政策的变迁历程进行系统梳理发现,其政策相继经历三个变迁阶段:试办探索初步发展期、扩招改革高速发展期、质量建设深化发展期。基于多源流理论分析框架,本文尝试对我国教育硕士专业学位政策的源流展... 详细信息

对1996-2023年我国教育硕士专业学位政策的变迁历程进行系统梳理发现,其政策相继经历三个变迁阶段:试办探索初步发展期、扩招改革高速发展期、质量建设深化发展期。基于多源流理论分析框架,本文尝试对我国教育硕士专业学位政策的源流展开分析。研究结果表明,学位供给与社会需求、培养质量与人才需求之间的矛盾形成了教育硕士专业学位政策议程的问题源流;党和国家的教育理念、国家的战略决策形成了教育硕士专业学位政策议程的政治源流;政府的积极推动、专家学者的咨政建言构成了教育硕士专业学位政策议程的政策源流。在三源流动态耦合之下,开启了教育硕士专业学位设置和试办、培养模式和培养质量探索、高质量发展的三扇“政策之窗”。

关键词：多源流理论研究生教育教育硕士专业学位教育政策政策演变

Instability Inception of a Single Rotor Embedded in a Transonic Stage with Partial Surge Inception

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Journal of Thermal Science 2022年第1期31卷 130-140页

作者： PAN Tianyu WU Wenqian ZHENG Mengzong li qiushi Reserach Institute of Aero-Engine Beihang UniversityBeijing 102206China School of Energy and Power Engineering Beihang UniversityBeijing 102206China Key Laboratory of Fluid and Power Machinery Ministry of EducationXihua UniversityChengdu 610039China

Partial surge is a type of instability inception discovered in our previous *** has been confirmed that partial surge is localized in the blade hub region,and the flow oscillation it caused will lead to the stall cells in the rotor *** since all information about partial surge is obtained from the compressor stage experiments,what will happen to the stall process after the stators are removed is also an issue that worth ***,in this paper,a series of experiments are carried out on the single rotor embedded in the transonic compressor stage with partial surge ***,the experimental results under uniform inlet conditions show that,although partial surge appears at high rotor speed in the stage case,it does not occur at any speed in the single rotor ***,it is found by numerical simulation that the absence of partial surge may be due to the insufficient rotor hub loading,so an experiment with increased hub loading is carried out,but still fails to trigger partial ***,the reason why partial surge doesn’t occur in the single rotor is *** these results,it can be concluded that partial surge cannot occur in the single rotor case,and the large-scale comer separation in the stator hub is considered to play an important role in the formation of partial surge.

关键词： transonic rotor instability inception partial surge blade loading corner separation

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多源流理论框架下我国职教专硕政策演变分析

职教发展研究 2024年第1期 83-90页

作者：李秋石刘钰莹天津大学教育学院天津300072 河北师范大学教师教育学院石家庄050024

基于多源流理论分析我国职教专硕政策演变历程,发现其在政策共同体的推动下实现了三源流耦合,并相继经历了三个阶段的演变:第一阶段职业教育的发展主要聚焦于中职教育,职教专硕的发展处于孕育期;第二阶段职教专硕正式设立,发展进入起步... 详细信息

基于多源流理论分析我国职教专硕政策演变历程,发现其在政策共同体的推动下实现了三源流耦合,并相继经历了三个阶段的演变:第一阶段职业教育的发展主要聚焦于中职教育,职教专硕的发展处于孕育期;第二阶段职教专硕正式设立,发展进入起步期;第三阶段相关政策文件相继出台,职教专硕得到了快速发展。分析发现,职教专硕实践能力的发展是当下面临的重要挑战,宜从多元主体协同培养、职校和企业两个实践场域交互融合、开展“岗课赛证”系统化实践活动、建立多元多样评价体系等四个方面培养其实践能力。

关键词：多源流理论职教专硕政策演变实践能力场域互动多元评价

Study on effects of thickness on airfoil-stall at low Reynolds numbers by cusp-catastrophic model based on GA(W)-1 airfoil

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Chinese Journal of Aeronautics 2020年第5期33卷 1444-1453页

作者： Zhiping li Peng ZHANG Tianyu PAN qiushi li Jian ZHANG National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics Beihang UniversityBeijing 100083China Collaborative Innovation Center for Advanced Aero-Engine Beihang UniversityBeijing 100083China School of Energy and Power Engineering Beihang UniversityBeijing 100083China Key Laboratory of Fluid and Power Machinery Ministry of EducationXihua UniversityChengdu 610039China

The phenomena of an airfoil stall present the behaviors of catastrophe and hysteresis at low Reynolds *** simulation results of two-dimensional airfoil GA(W)-1 show that the width of the hysteresis loop of airfoil stall will gradually decrease and even disappear with the decrease of thickness *** nonlinear characteristics are in accordance with the topological features of the cusp catastrophic *** to the topological invariant principle,a novel topological mapping method is developed to establish the mapping relationship between cusp catastrophic model and stall characteristics of the airfoil,then the effect of thickness ratio on airfoil stall is successfully described quantitatively by cusp catastrophic ***,based on the established topological mapping relationship,combined with the mean flow field of the airfoil stall,potential function approach of cusp catastrophic model is first introduced to interpret the catastrophe and hysteresis of the airfoil stall,and it is found that as the thickness ratio decreases,the system’s maximal potential energy gradually disappears,and the short separation bubble at the leading edge of the airfoil changes to long separation bubble,so the airfoil stall changes from a bistable system to a monostable system.

关键词： Airfoil Catastrophe theory Low Reynolds number Potential function Thickness ratio

Streamwise-body-force-model for rapid simulation combining internal and external flow fields

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Chinese Journal of Aeronautics 2016年第5期29卷 1205-1212页

作者： Cui Rong li qiushi Pan Tianyu Zhang Jian National Key Laboratory on Aero-Engines Beihang University Collaborative Innovation Center of Advanced Aero-Engine Beihang University Department of Engine Project Aviation Industry Corporation of China

A streamwise-body-force-model （SBFM） is developed and applied in the overall flow simulation for the distributed propulsion system, combining internal and external flow fields. In view of axial stage effects, fan or compressor effects could be simplified as body forces along the streamline. These body forces which are functions of local parameters could be added as source terms in Navier-Stokes equations to replace solid boundary conditions of blades and hubs. The val- idation of SBFM with uniform inlet and distortion inlet of compressors shows that pressure performance characteristics agree well with experimental data. A three-dimensional simulation of the integration configuration, via a blended wing body aircraft with a distributed propulsion system using the SBFM, has been completed. lift coefficient and drag coefficient agree well with wind tunnel test results. Results show that to reach the goal of rapid integrated simulation combining internal and external flow fields, the computational fluid dynamics method based on SBFM is reasonable.

关键词： Aircraft Blended wing body Boundary layer ingestion Distributed propulsion sys-tem Integrated simulations Streamwise-body-force-model