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Instability characteristics of the East Asian Monsoon recorded by high-resolution loess sections from the last interglacial (MIS5)

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Science China Earth Sciences 2007年第7期50卷 1067-1075页

作者： GUAN qingyu PAN BaoTian GAO HongShan LI BingYuan WANG JunPing su Huai Key Laboratory of Western China’s Environmental Systems(MOE) Lanzhou UniversityLanzhou 730000China Institute of Geographical Sciences and Natural Resources Chinese Academy of SciencesBeijing 100101China

The selection of high-resolution loess sections is needed in order to determine the climatic variability of the East Asian Monsoon during the last interglacial. Two sequences of S1 on the eastern and west-ern sides of the Liupan Mountain were both composed of five paleosol layers and four loess layers,indicating that there were five strong summer monsoon events and four strong winter monsoon events in MIS5. This corresponds with other records of the East Asian Monsoon,along with NGRIP and the North Atlantic records,implying that the climate of the Northern Hemisphere was very instable during the last interglacial. Two layers of paleosols and one layer of loess had developed during MIS5a and MIS5c. Compared with MIS5e,the climate in MIS5a and MIS5c fluctuated more intensively on a millen-nial scale,whereas the climate was relatively stable in MIS5e.

关键词： last interglacial paleosol East Asian monsoon Shagou loess section Wangguan loess section Liupan Mountain

Research on the Freezing Phenomenon of Quantum Correlation by Machine Learning

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Computers, Materials & Continua 2020年第12期65卷 2143-2151页

作者： Xiaoyu Li Qinsheng Zhu Yiming Huang Yong Hu qingyu Meng Chenjing su Qing Yang Shaoyi Wu Xusheng Liu School of Information and Software Engineering University of Electronic Science and Technology of ChinaChengdu610054China School of Physics University of Electronic Science and Technology of ChinaChengdu610054China Department of Chemistry and Biochemistry Utah State UniversityLoganUtah84322USA

Quantum correlation shows a fascinating nature of quantum mechanics and plays an important role in some physics topics,especially in the field of quantum *** correlations of the composite system can be quantified by resorting to geometric or entropy methods,and all these quantification methods exhibit the peculiar freezing *** challenge is to find the characteristics of the quantum states that generate the freezing phenomenon,rather than only study the conditions which generate this phenomenon under a certain quantum *** essence,this is a classification *** learning has become an effective method for researchers to study classification and feature *** this work,we prove that the machine learning can solve the problem of X form quantum states,which is a problem of physical ***,we apply the density-based spatial clustering of applications with noise(DBSCAN)algorithm and the decision tree to divide quantum states into two different *** goal is to classify the quantum correlations of quantum states into two classes:one is the quantum correlation with freezing phenomenon for both Rènyi discord(α=2)and the geometric discord(Bures distance),the other is the quantum correlation of non-freezing *** results demonstrate that the machine learning method has reasonable performance in quantum correlation research.

关键词： Machine learning quantum correlation freezing phenomenon Rènyi discord geometric discord

VIBRATION ANALYSIS OF ELASTIC PLATE suBMERGED IN INCOMPRESSIBLE VISCOUS FLUID BY COUPLING FINITE ELEMENT METHOD

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Acta Mechanica Solida Sinica 1998年第1期11卷 1-12页

作者： Wang Hui Pan qingyu Cen Zhangzhi Tsing Hua Univ Dept Engn Mech Beijing 100084 Peoples R China

The interaction problem of an elastic structure and anincompressible viscous fluid is solved through a computationalprocedure proposed in this paper. The fluid region is considered tobe bounded though without free surface boundary. The discrete fluiddomain is described by the stream- line upwind/Petrov-Galerkin finiteelement method. The arbitrary Lagrangian-Eulerian description isemployed to treat the moving interface between the structure and thefluid. The predictor-multicorrec- tor method is adopted to solve thecoupling finite element equations. The results of three numerical ex-amples show the effectiveness of the procedure.

关键词： plate vibration fluid-structure interaction su/PG method

偏高岭土-矿渣地聚物宏观性能试验及Lasso回归模型

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复合材料学报 2022年第11期39卷 5474-5485页

作者：钟卿瑜粟淼彭晖长沙理工大学土木工程学院长沙410114

设计120组偏高岭土-矿渣地聚物净浆试验,探讨了碱激发剂浓度、模数、液固比这三个变量对地聚物净浆抗压强度、流动度和凝结时间的影响规律。基于获得的试验数据,建立Lasso多元回归模型预测了偏高岭土-矿渣地聚物净浆7天和28天抗压强度... 详细信息

设计120组偏高岭土-矿渣地聚物净浆试验,探讨了碱激发剂浓度、模数、液固比这三个变量对地聚物净浆抗压强度、流动度和凝结时间的影响规律。基于获得的试验数据,建立Lasso多元回归模型预测了偏高岭土-矿渣地聚物净浆7天和28天抗压强度、流动度、初凝及终凝时间。试验结果表明:(1)抗压强度随碱激发剂浓度的增大而提高,随液固比增大而降低,随模数的增大先提高后降低;(2)液固比增大,凝结时间延长;而模数和浓度对凝结时间的影响由碱激发剂的硅含量和碱含量决定;(3)流动度主要与碱激发剂的黏稠程度和液固比有关。模型验证结果表明:采用Lasso算法对回归模型进行正则化,避免了回归系数过大而导致的过拟合现象,提出的回归模型能准确预测偏高岭土-矿渣地聚物净浆各项宏观性能,测试集数据中的预测值与试验值的相关性系数均大于0.92。

关键词：碱激发抗压强度流动度凝结时间机器学习地聚物

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基于二维DFT域全相位滤波的波包设计

光电子．激光 2022年第2期33卷 193-202页

作者：孔庆羽苏飞天津理工大学集成电路科学与工程学院天津300384

信号滤波、谱分析和自适应信号处理在全相位信号处理领域中已得到广泛应用。本文在一维全相位信号处理方法的基础上,给出二维全相位变换的数学表达式,并构建了相应的信号处理系统图。其次,分析出全相位变换具有线性相位的充要条件,进而... 详细信息

信号滤波、谱分析和自适应信号处理在全相位信号处理领域中已得到广泛应用。本文在一维全相位信号处理方法的基础上,给出二维全相位变换的数学表达式,并构建了相应的信号处理系统图。其次,分析出全相位变换具有线性相位的充要条件,进而提出全相位波包的概念。第三,分别选择Bartlett和Blackman作为基窗,仿真出20个全相位正交波包。最后,借助全相位波包顺利地对图像展开了分解验证。分析表明,全相位波包可以实现对图像的多层分解,并在时域和频域上得到多种分辨率的子图。此分析方法在图像数据的压缩,边缘检验和自适应信号处理等诸多方面有着十分广泛的应用领域和发展前景。

关键词：波包多分辨率分析(multi-resolution analysis,MRA) 全相位线性相位基窗

Electrical stimulation with polypyrrole-coated polycaprolactone/silk fibroin scaffold promotes sacral nerve regeneration by modulating macrophage polarisation

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Biomaterials Translational 2024年第2期5卷 157-174页

作者： Haofeng Cheng Jun Bai Xingyu Zhou Nantian Chen qingyu Jiang Zhiqi Ren Xiangling Li Tianqi su Lijing Liang Wenli Jiang Yu Wang Jiang Peng Aijia Shang School of Medicine Nankai UniversityTianjinChina Department of Neurosurgery Chinese PLA General HospitalBeijingChina Institute of Orthopedics Chinese PLA General HospitalBeijing Key Lab of Regenerative Medicine in OrthopedicsKey Laboratory of Musculoskeletal Trauma&War Injuries PLABeijingChina Co-innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Graduate School of Chinese PLA General Hospital BeijingChina Department of Ultrasound Chinese PLA General HospitalBeijingChina

Peripheral nerve injury poses a great threat to neurosurgery and limits the regenerative potential of sacral nerves in the neurogenic *** remains unknown whether electrical stimulation can facilitate sacral nerve regeneration in addition to modulate bladder *** objective of this study was to utilise electrical stimulation in sacra nerve crush injury with newly constructed electroconductive scaffold and explore the role of macrophages in electrical stimulation with crushed *** a result,we generated a polypyrrole-coated polycaprolactone/silk fibroin scaffold through which we applied electrical *** electrical stimulation boosted nerve regeneration and polarised the macrophages towards the M2 *** in vitro test using bone marrow derived macrophages revealed that the pro-regenerative polarisation of M2 were significantly enhanced by electrical *** analysis showed that the expression of signal transducer and activator of transcriptions(STATs)was differentially regulated in a way that promoted M2-related genes *** work indicated the feasibility of electricals stimulation used for sacral nerve regeneration and provided a firm demonstration of a pivotal role which macrophages played in electrical stimulation.

关键词： electrical stimulation JAK-STAT signalling pathway macrophage polarisation peripheral nerve regeneration polypyrrole sacral nerve injury

梯度锚固预应力NSM CFRP加固RC梁静力及疲劳性能研究

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湖南大学学报（自然科学版） 2022年第1期49卷 113-123页

作者：龚爽彭晖粟淼张建仁钟卿瑜长沙理工大学土木工程学院湖南长沙410114 桥梁工程安全控制教育部重点实验室(长沙理工大学) 湖南长沙410114

针对表层嵌贴预应力CFRP加固梁因黏结端部应力集中导致混凝土保护层易剥离破坏的问题,提出了在CFRP端部设置梯度预应力的构造措施,并通过构件试验系统研究了梯度锚固预应力CFRP加固梁的静载和疲劳性能.试验结果表明:在静力荷载作用下,... 详细信息

针对表层嵌贴预应力CFRP加固梁因黏结端部应力集中导致混凝土保护层易剥离破坏的问题,提出了在CFRP端部设置梯度预应力的构造措施,并通过构件试验系统研究了梯度锚固预应力CFRP加固梁的静载和疲劳性能.试验结果表明:在静力荷载作用下,梯度锚固预应力CFRP加固梁极限荷载较普通表层嵌贴预应力CFRP加固梁最大提高35.06%,破坏模式由端部保护层剥离破坏转变为保护层剥离与CFRP断裂复合破坏,梯度锚固预应力CFRP加固显著提高了RC梁的静载性能,且有明显的黏结应力峰值传递现象;疲劳荷载下梯度锚固预应力加固梁的疲劳寿命也较普通嵌贴加固梁显著提高,且疲劳破坏模式由端部保护层剥离转变为纵向受拉钢筋疲劳断裂;梯度锚固预应力构造显著增强了加固梁抵抗剥离破坏发生的能力,提高了加固梁疲劳性能.

关键词：表层嵌贴 CFRP 梯度锚固静力性能疲劳性能

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串热源模型及其在焊接数值模拟中的应用

机械工程学报 2001年第4期37卷 25-28,43页

作者：蔡志鹏赵海燕吴甦鹿安理史清宇清华大学机械系北京100084

通过分析焊接热源的特征要素 ,在高斯热源的基础上 ,根据输入热功率相当提出段热源模型 ,并与点热源结合 ,进一步提出更加灵活实用的串热源模型。经验证明 ,可在保持精度的同时大幅度地缩短计算时间 ,从而使实际构件工艺的模拟、优化成... 详细信息

通过分析焊接热源的特征要素 ,在高斯热源的基础上 ,根据输入热功率相当提出段热源模型 ,并与点热源结合 ,进一步提出更加灵活实用的串热源模型。经验证明 ,可在保持精度的同时大幅度地缩短计算时间 ,从而使实际构件工艺的模拟、优化成为可行。还利用该模型进行桥式起重机腹板切割工艺的模拟。

关键词：焊接串行源模型数值模拟桥式起重机

督学责任区建设中的问题与改进路径——基于对X省Y市调研的思考

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现代教育管理 2016年第1期 59-64页

作者：张清宇苏君阳北京师范大学北京100875

督学责任区制度是我国教育督导领域的一项制度创新,也是我国深化教育督导改革、提高教育督导效能的重要尝试。通过对X省Y市的实地调研,发现目前督学责任区建设中存在督导范围太广、督导方案缺乏可操作性、没有建立起跟踪督导机制、责任... 详细信息

督学责任区制度是我国教育督导领域的一项制度创新,也是我国深化教育督导改革、提高教育督导效能的重要尝试。通过对X省Y市的实地调研,发现目前督学责任区建设中存在督导范围太广、督导方案缺乏可操作性、没有建立起跟踪督导机制、责任督学队伍结构不合理等问题。在今后的督学责任区建设中,应进一步厘清责任区督导内容,制定切实可行的责任区督导方案,完善责任区督导结果使用制度,优化责任督学队伍结构,提高责任督学的专业化水平,更好地发挥其在规范学校办学行为、提高教育教学质量过程中的作用。

关键词：督学责任区责任督学教育督导