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产学研深度融合创新联合体:概念衍生、特征类型与推进路径

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科技进步与对策 2024年第10期41卷 150-160页

作者：张羽飞孙祺李桂荣原长弘河北经贸大学工商管理学院河北经贸大学科技创新政策研究中心河北石家庄050061 西安交通大学管理学院陕西西安710049

产学研深度融合创新联合体是中国产学研实践的最新模式,是中国式创新在产学研方面的深刻体现,但学术界对这一新现象关注不足,难以有效推进中国式现代化情景下产学研深度融合创新联合体建设。鉴于此,以产学研深度融合创新联合体这一中国... 详细信息

产学研深度融合创新联合体是中国产学研实践的最新模式,是中国式创新在产学研方面的深刻体现,但学术界对这一新现象关注不足,难以有效推进中国式现代化情景下产学研深度融合创新联合体建设。鉴于此,以产学研深度融合创新联合体这一中国产学研新实践现象为切入点,按照“概念衍生—特征类型—推进路径”分析框架进行逐层解构。首先,梳理产学研深度融合创新联合体政策演进和研究脉络,廓清产学研深度融合创新联合体概念内涵与外延;其次,归纳产学研深度融合创新联合体特征,并基于主导组织视角总结出4类典型的产学研深度融合创新联合体;再次,立足新时代高质量发展要求,为推进政产学研用深度融合新型创新联合体建设提出相关对策建议;最后,构建产学研深度融合创新联合体整合框架,并提出未来研究方向。研究结论有助于拓展产学研深度融合与创新联合体研究,并为中国政产学研各方推进产学研深度融合创新联合体建设提供实践启示。

关键词：产学研深度融合创新联合体概念衍生特征类型推进路径理论框架

石英纱线/石英纤维毡三维织物的设计及其隔热性能

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纺织学报 2024年第6期45卷 53-58页

作者：李久刚石玉菲刘可帅李文斌柯贵珍武汉纺织大学纺织科学与工程学院湖北武汉430200 武汉纺织大学纺织新材料与先进加工技术省部共建国家重点实验室湖北武汉430200

为充分利用石英纱线及其纤维毡良好的隔热效果制备隔热性能优异的石英纱线/石英纤维毡三维织物,采用石英纱线和纤维毡在小样织机上进行三维立体编织,针对石英纱线/石英纤维毡三维织物不易编织等诸多问题,对织机综丝综框进行降低摩擦处理... 详细信息

为充分利用石英纱线及其纤维毡良好的隔热效果制备隔热性能优异的石英纱线/石英纤维毡三维织物,采用石英纱线和纤维毡在小样织机上进行三维立体编织,针对石英纱线/石英纤维毡三维织物不易编织等诸多问题,对织机综丝综框进行降低摩擦处理;然后采用控制变量法和实验对比法,对所得石英纱线/石英纤维毡三维织物在热环境下的隔热性能进行测试表征,对其加热状态下的温度和外观形状的变化趋势和规律进行探讨。实验结果表明:石英纱线/石英纤维毡三维织物在300~700℃时,平均隔热保留率是相等厚度普通石英纤维织物的4倍,验证了石英纱线/石英纤维毡三维织物的优越隔热性能。确定了石英纱线/石英纤维毡三维织物具有良好的整体性能和隔热性,能够作为航天飞行器的外部隔热材料抵挡高温冲刷,因此对石英纱线/石英纤维毡三维织物性能的研究具有深远意义。

关键词：石英纱线纤维毡三维织物间隔织物隔热性能

海上风电桩基础打桩过程中桩周土强度弱化模型试验研究

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太阳能学报 2024年第1期45卷 242-250页

作者：刘润苏春阳李成凤贾沼霖袁新勇刘玉飞天津大学建筑工程学院天津300350 河北工程大学水利水电学院邯郸056038 华电重工股份有限公司天津300010

在海上风电桩基础的打桩过程中,桩周土体强度会产生明显的弱化现象,为明确桩周土体强度弱化影响因素以及弱化规律,开展模型试验模拟打桩过程,研究在不同锤击能量下,不同桩体尺寸情况下,桩身侧摩阻力随着贯入深度的变化规律,建立描述土... 详细信息

在海上风电桩基础的打桩过程中,桩周土体强度会产生明显的弱化现象,为明确桩周土体强度弱化影响因素以及弱化规律,开展模型试验模拟打桩过程,研究在不同锤击能量下,不同桩体尺寸情况下,桩身侧摩阻力随着贯入深度的变化规律,建立描述土体强度弱化规律的弱化公式,并通过打桩软件对多个海上风电桩基础工程中大直径及超大直径钢管桩的打桩实测数据进行打桩分析。研究结果表明:在打桩过程中,桩周土体强度的弱化同时受到桩体质量以及锤击能量的影响,桩基质量和锤击能量越大,土体强度弱化程度越高。在打桩的可打入分析中,采用该文所建立的弱化公式可模拟出不同尺寸桩体沉桩时土体强度的折减规律。

关键词：海上风电场桩基础打桩土体强度弱化模型试验

Overexpression of Stella improves the efficiency of nuclear transfer reprogramming

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Journal of Genetics and Genomics 2017年第7期44卷 363-366页

作者： Leyun Wang Fei Teng Xuewei Yuan Chao liu qiang Wang yufei li Tongtong Cui Tianda li Zhonghua liu Qi Zhou College of life Science Northeast Agricultural UniversityHarbin 150030China State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101 China University of Chinese Academy of Sciences Beijing 100049China

In mammalians, the state of a somatic cell can be reversed from the terminal state to the totipotent state by means of somatic cell nuclear transfer （SCNT）（Gurdon, 1962） or induced pluripotent stem cells （iPSCs）（Takahashi and Yamanaka, 2006）. The DNA methylation and transcriptome profiles of embryonic stern cells （ESCs） derived from SCNT embryos （NT-ESCs） correspond closely to those of ESCs derived from in vitro fertilization embryos （IVF- ESCs）. In contrast, iPSCs differ from both NT-ESCs and IVF-ESCs in that they retain the residual DNA methylation patterns of their parental somatic cells. As SCNT can be used to faithfully reprogram human somatic cells to pluripotency, it is ideal for cell replacement therapies （Ma et al., 2014）. Following the successful production of the first human NT-ESCs （Tachibana et al., 2013） and the later gen- eration of human NT-ESCs based on cells from elderly adults or pa- tient cells （Chung et al., 2014; Yamada et al., 2014）, a version of the SCNT technique for human therapeutics comes closer to reality. However, no matter what animal species or donor cell types are used in the cloned process, the cloning efficiency remains undesir- able. Besides, there are many phenotypic abnormalities in cloned animals, containing frequent embryonic and perinatal death and placentomegaly, and the underlying mechanisms remain unclear （Yang et al, 2007）.

关键词： of cell as that Overexpression of Stella improves the efficiency of nuclear transfer reprogramming TSA were

膨润土和腐植酸对猪粪堆肥Zn、Cu钝化和微生物群落的影响

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农业环境科学学报 2024年第4期43卷 937-946页

作者：朱桃川李泽康明玉飞李传福高舒董智焦树英李永强山东农业大学资源与环境学院土肥高效利用国家工程研究中心山东泰安271018 山东农业大学林学院山东泰安271018

为提高堆肥资源化利用,减少农业面源污染,通过单独添加10%膨润土(BT)、10%腐植酸(HA)以及2.5%膨润土+7.5%腐植酸(BH1)、5.0%膨润土+5.0%腐植酸(BH2)和7.5%膨润土+2.5%腐植酸(BH3)混合添加的方式,开展了其对猪粪堆肥重金属Zn、Cu钝化效... 详细信息

为提高堆肥资源化利用,减少农业面源污染,通过单独添加10%膨润土(BT)、10%腐植酸(HA)以及2.5%膨润土+7.5%腐植酸(BH1)、5.0%膨润土+5.0%腐植酸(BH2)和7.5%膨润土+2.5%腐植酸(BH3)混合添加的方式,开展了其对猪粪堆肥重金属Zn、Cu钝化效果及微生物群落组成影响的研究。结果表明:添加膨润土和腐植酸延长了堆肥高温期,BH3处理的可溶性有机碳(DOC)降解率达40.52%,较对照(CK)显著提高12.46个百分点(P<0.05)。堆肥过程中,BH3处理下的Cu生物有效态占比较堆肥前下降12.17个百分点,而Zn可氧化态占比较堆肥前上升29.74个百分点,降幅和升幅均显著高于其余处理(P<0.05)。与CK和单独添加处理相比,混合添加可显著提高重金属Cu、Zn钝化效率,BH3处理对Cu和Zn的钝化率分别达79.84%和36.97%,较CK分别显著提高47.80个百分点和23.09个百分点(P<0.05)。膨润土和腐植酸混合添加,不同程度地促进了厚壁菌门、梭菌纲等参与纤维降解的有益物种相对丰度的升高。BH3处理下拟杆菌门和拟杆菌纲的相对丰度显著高于同时期的其他各处理。研究表明,膨润土和腐植酸与猪粪共堆肥更有利于堆肥腐熟和重金属钝化,混合添加7.5%膨润土和2.5%腐植酸为最佳推荐比例。

关键词：猪粪堆肥膨润土腐植酸重金属钝化微生物

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超声辅助金刚石线锯复合切割技术的研究进展

制造技术与机床 2024年第5期 107-113页

作者：李洪浩高玉飞张乃军山东大学机械工程学院高效洁净机械制造教育部重点实验室山东济南250061

硬脆材料与复合材料等高性能材料在多个领域广泛应用,其切割主要采用金刚石线锯加工技术。近年来,对切割加工质量和效率的要求不断提高,超声辅助金刚石线锯复合切割技术逐渐发展起来。超声辅助金刚石线锯复合切割技术提高了锯切效率和... 详细信息

硬脆材料与复合材料等高性能材料在多个领域广泛应用,其切割主要采用金刚石线锯加工技术。近年来,对切割加工质量和效率的要求不断提高,超声辅助金刚石线锯复合切割技术逐渐发展起来。超声辅助金刚石线锯复合切割技术提高了锯切效率和加工表面质量,延长了锯丝服役寿命,是未来的重要发展方向。文章从超声辅助金刚石线锯复合切割技术的加工原理、加工质量和影响因素等方面概述了该技术的研究现状,并对未来需进一步研究的问题和发展方向进行了展望。

关键词：金刚石线锯超声振动加工质量复合加工

Transfer learning from two-dimensional supercritical airfoils to three-dimensional transonic swept wings

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中国航空学报:英文版 2023年第9期36卷 96-110页

作者： Runze li yufei ZHANG Haixin CHEN School of Aerospace Engineering Tsinghua UniversityBeijing 100084China

Machine learning has been widely utilized in flow field modeling and aerodynamic optimization.However,most applications are limited to two-dimensional problems.The dimensionality and the cost per simulation of three-dimensional problems are so high that it is often too expensive to prepare sufficient samples.Therefore,transfer learning has become a promising approach to reuse well-trained two-dimensional models and greatly reduce the need for samples for threedimensional problems.This paper proposes to reuse the baseline models trained on supercritical airfoils to predict finite-span swept supercritical wings,where the simple swept theory is embedded to improve the prediction accuracy.Two baseline models are investigated:one is commonly referred to as the forward problem of predicting the pressure coefficient distribution based on the geometry,and the other is the inverse problem that predicts the geometry based on the pressure coefficient distribution.Two transfer learning strategies are compared for both baseline models.The transferred models are then tested on complete wings.The results show that transfer learning requires only approximately 500 wing samples to achieve good prediction accuracy on different wing planforms and different free stream conditions.Compared to the two baseline models,the transferred models reduce the prediction error by 60%and 80%,respectively.

关键词： Inverse design Pressure distribution Supercritical airfoils Swept wings Transfer learning

Motion model for describing the quantity of air in droplets through changing the structure of air induction nozzle

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International Journal of Agricultural and Biological Engineering 2021年第5期14卷 35-40页

作者： Jun Hu Changxi liu Zhichong Wang yufei li Jianli Song Yajia liu Xin Chu College of Engineering Heilongjiang Bayi Agricultural UniversityDaqing 163319HeilongjiangChina Heilongjiang Provincial Key Laboratory of Intelligent Agricultural Machinery Equipment Daqing 163319HeilongjiangChina Heilongjiang Province Conservation Tillage Engineering Technology Research Center Daqing 163319HeilongjiangChina College of Science China Agriculture UniversityBeijing 100193China

Air induction nozzles possess good anti-drift performance,the throat and orifice sizes of the nozzles are the main design parameters that affecting atomization.Therefore,Venturi tube nozzles and conventional flat fan nozzles were assembled together to investigate the flow rate,droplet size,the quantity of air in droplets affected by a single design parameter of nozzles with applying high speed camera and Spraytec laser diffraction system.The results showed that:the flow rate of the air induction nozzle depended only on the throat size of Venturi tube and pressure,and it was proportional to the throat size of Venturi tube at the same pressure;The flat fan nozzle’s orifice size and Venturi tube size significantly affected volume median diameter of droplets,which generally increased after adding surfactant;A new model was established after optimizing classical equation for calculating the percentage of intake air in droplets and studying the effects of throat and orifice size of air induction nozzles on spray characteristics.By variance analysis,it was verified that the new model of quantity of air in droplets produced by all connected nozzles was correct.The calculation showed that the bubbles sizes ranged at 200-900μm and were in proportion to the droplet size with the percentage of intake air of 10%to 90%.Contrast to the change of volume median diameter and droplet velocity,the existence of intake air could influence their change degree to some extent.

关键词： throat orifice spray characteristic model of droplet motion air induction nozzle

Pressure distribution feature-oriented sampling for statistical analysis of supercritical airfoil aerodynamics

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Chinese Journal of Aeronautics 2022年第4期35卷 134-147页

作者： Runze li yufei ZHANG Haixin CHEN School of Aerospace Engineering Tsinghua UniversityBeijing 100084China

In the field of supercritical wing design, various principles and rules have been summarized through theoretical and experimental analyses. Compared with black-box relationships between geometry parameters and performances, quantitative physical laws about pressure distributions and performances are clearer and more beneficial to designers. With the advancement of computational fluid dynamics and computational intelligence, discovering new rules through statistical analysis on computers has become increasingly attractive and affordable. This paper proposes a novel sampling method for the statistical study on pressure distribution features and performances, so that new physical laws can be revealed. It utilizes an adaptive sampling algorithm, of which the criteria are developed based on Kullback–Leibler divergence and Euclidean distance.In this paper, the proposed method is employed to generate airfoil samples to study the relationships between the supercritical pressure distribution features and the drag divergence Mach number as well as the drag creep characteristic. Compared with conventional sampling methods, the proposed method can efficiently distribute samples in the pressure distribution feature space rather than directly sampling airfoil geometry parameters. The corresponding geometry parameters are searched and found under constraints, so that supercritical airfoil samples that are well distributed in the pressure distribution space are obtained. These samples allow statistical studies to obtain more reliable and universal aerodynamic rules that can be applied to supercritical airfoil designs.

关键词： Adaptive sampling Output space Statistics Pressure distribution features Supercritical airfoil