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NONPARAMETRIC REGRESSION UNDER DOUBLE-SAMPLING DESIGNS

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Journal of Systems Science & Complexity 2011年第1期24卷 167-175页

作者： Xuejun jiang Jiancheng jiang Yanling LIU School of Mathematical Sciences Peking University Beijing 100871 China School of Statistics and Mathematics Zhongnan University of Economics and Law Wuhan 430073China Department of Mathematics and Statistics University of North Carolina Charlotte North Carolina 28223 USA School of Mathematical Sciences Peking University Beijing 100871 China

This paper studies nonparametric estimation of the regression function with surrogate outcome data under double-sampling designs, where a proxy response is observed for the full sample and the true response is observed on a validation set. A new estimation approach is proposed for estimating the regression function. The authors first estimate the regression function with a kernel smoother based on the validation subsample, and then improve the estimation by utilizing the information on the incomplete observations from the non-validation subsample and the surrogate of response from the full sample. Asymptotic normality of the proposed estimator is derived. The effectiveness of the proposed method is demonstrated via simulations.

关键词： Local linear smoother surrogate validation sample

In situ monitoring the internal of lithium ion batteries

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Acta Mechanica Sinica 2021年第6期37卷 902-903页

作者： Hanqing jiang School for Engineering of Matter Transport and EnergyArizona State UniversityTempe85287USA

The temperature evolution inside the lithium-ion battery would significantly influence its performance and ***,an in-situ technology that allows for monitoring and transmitting the internal temperature signal of the cylindrical battery has been developed,and whereby early safety alert of the abnormal cases inside the batteries could be envisaged.

关键词： battery lithium cylindrical

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介质微球超分辨光学成像:原理、技术与应用

北京工业大学学报 2025年第1期51卷 100-120页

作者：李红梅闫胤洲蒋毅坚北京工业大学机械与能源工程学院北京100124 北京工业大学物理与光电工程学院北京100124

光学显微技术在生物学、医学、材料学、精密测量学等领域扮演着至关重要的角色,为微纳尺度的探索提供了强大的工具。然而,传统光学显微系统受到衍射极限的制约,最大分辨率极限约为光波长的一半(λ/2)。近年来,突破衍射极限、实现更高成... 详细信息

光学显微技术在生物学、医学、材料学、精密测量学等领域扮演着至关重要的角色,为微纳尺度的探索提供了强大的工具。然而,传统光学显微系统受到衍射极限的制约,最大分辨率极限约为光波长的一半(λ/2)。近年来,突破衍射极限、实现更高成像分辨率成为显微成像领域的研究热点。介质微球透镜通过调控光场,能够将入射光束聚焦于微球底部的极窄区域形成光子纳米射流,打破了阿贝(Abbe)衍射极限,使出射光束半峰全宽小于λ/2。与其他超分辨成像技术相比,微球超分辨成像具有简单直接、无须荧光染料标记、实时成像、可与现有显微系统相兼容等优势,为学术研究和实际应用开辟了新的机遇。该综述首先介绍了介质微球超分辨光学成像原理;随后,详细分析了影响微球超分辨光学成像能力的关键因素,包括微球光学性质、适用环境以及可控性等;最后,探讨了微球超分辨光学成像技术在生物医学、半导体器件、纳米材料科学领域中的应用。此外,还展望了微球超分辨光学成像技术未来发展面临的主要挑战。

关键词：介质微球透镜超分辨成像光学纳米成像远场纳米显微镜光子纳米射流非荧光纳米显微镜

Revisiting coherent structures in low-speed turbulent boundary layers

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Applied Mathematics and Mechanics(English Edition) 2019年第2期40卷 261-272页

作者： Xianyang jiang State Key Laboratory for Turbulence and Complex Systems Peking University Department of Aeronautics and Astronautics College of EngineeringPeking University

Coherent structures are essential for the momentum exchange and turbulence production in wall-bounded turbulent flows. Diversified coherent structures have been observed in turbulent boundary layers, and hairpin-based vortices dominate most of the relevant literature. However, there is no consensus yet on the origin and forming mechanism of hairpin vortices. Herein, five cornerstones pertaining to the framework of hairpin-based coherent structures are reviewed, and three different hairpin generation mechanisms are clarified. Next, the time-resolved tomographic particle image velocimetry(Tomo-PIV) is used in an early turbulent boundary layer(Re_θ= 420) to investigate the origin of hairpin vortices. The timelines reveal a triangular bulge in the low-speed streak(LSS), and the initial roll-up occurs at two sides of it. Meanwhile, the material surfaces manifest as a three-dimensional(3D) wave structure in the LSS, which may support the model of a soliton-like coherent structure(SCS). Subsequently, the method of Lagrangian-averaged vorticity deviation is used to detect early vortices. We find that the 3D wave structure is flanked by two vortices, thus confirming the roll-up of timelines and demonstrating the advantage of the Lagrangian criteria in capturing structures in complex flows. These results suggest that various coherent structures may evolve from the metamorphosis of 3D wave structures and their later interaction. Finally, the limitations of traditional experimental and post-processing tools are discussed.

关键词： coherent structure hairpin vortex soliton-like coherent structure(SCS)

AN APPROACH TO GROUP DECISION MAKING BASED ON INTERVAL FUZZY PREFERENCE RELATIONS

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Journal of Systems Science and Systems Engineering 2007年第1期16卷 113-120页

作者： Yunliang jiang School of Information Engineering Huzhou University Huzhou 313000 China Institute of Artificial Intelligence Zhejiang University Hangzhou 310027 China

In this paper, we investigate group decision making problems where the decision information given by decision makers takes the form of interval fuzzy preference relations. We first give an index to measure the similarity degree of two interval fuzzy preference relations, and utilize the similarity index to check the consistency degree of group opinion. Furthermore, we use the error-propagation principle to determine the priority vector of the aggregated matrix, and then develop an approach to group decision making based on interval fuzzy preference relations. Finally, we give an example to illustrate the developed approach.

关键词： Group decision making interval fuzzy preference relation similarity index aggregation

1980-2020年汾河流域耕地显性转型时空分异及其驱动力

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水土保持研究 2025年第1期32卷 257-265,284页

作者：姜民武志平付建新太原师范学院地理科学学院山西晋中030619 太原师范学院城镇与区域发展研究所山西晋中030619 太原师范学院汾河流域地表过程与资源生态安全山西省重点实验室山西晋中030619 太原师范学院碳中和研究院山西晋中030619

[目的]刻画耕地利用转型变化特征,揭示耕地转型发展规律,为汾河流域耕地资源保护和乡村转型发展提供理论支撑和参考依据。[方法]基于1980年、1990年、2000年、2010年、2020年土地利用遥感影像数据,利用耕地转型速度、转移矩阵和地理探... 详细信息

[目的]刻画耕地利用转型变化特征,揭示耕地转型发展规律,为汾河流域耕地资源保护和乡村转型发展提供理论支撑和参考依据。[方法]基于1980年、1990年、2000年、2010年、2020年土地利用遥感影像数据,利用耕地转型速度、转移矩阵和地理探测器方法,分析了汾河流域耕地利用转型的时空分异特征,并探测了其驱动因子。[结果](1)1980-2020年,流域内耕地面积减少10.59万hm^(2),其中,耕地转为建设用地的面积最大,草地是转入耕地最多的地类,占转入总面积的59.37%。(2)1980-2020年,汾河流域耕地利用转型速度呈波动下降趋势,其中中游耕地减少最明显,人地矛盾突出。(3)自然因子对耕地转型影响程度明显强于社会经济因子,其中气温q值最大,达0.72。自然因子之间的交互作用对耕地转型的解释力更强。[结论]汾河流域耕地利用转型受自然和社会经济因素共同影响,先后经历了缓和平稳、转型加剧、矛盾尖锐和收敛平衡不同阶段,空间集聚性特征显著,将指导该流域耕地资源合理、有序利用。

关键词：耕地转型空间转型地理探测汾河流域

Normalization in Riemann Tensor Polynomial Ring

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Journal of Systems Science & Complexity 2018年第2期31卷 569-580页

作者： LIU jiang Department of Systems Science University of Shanghai for Science and Technology Glorious Sun School of Business and Management Donghua University

It is one of the oldest research topics in computer algebra to determine the equivalence of Riemann tensor indexed polynomials. However, it remains to be a challenging problem since Grbner basis theory is not yet powerful enough to deal with ideals that cannot be finitely generated. This paper solves the problem by extending Grbner basis theory. First, the polynomials are described via an infinitely generated free commutative monoid ring. The authors then provide a decomposed form of the Grbner basis of the defining syzygy set in each restricted ring. The canonical form proves to be the normal form with respect to the Grbner basis in the fundamental restricted ring, which allows one to determine the equivalence of polynomials. Finally, in order to simplify the computation of canonical form, the authors find the minimal restricted ring.

关键词： Canonical form Einstein summation convention monoid ring nD symbolic computation,Riemann tensor.

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激光技术在食品3D打印中的应用及发展趋势

食品科学 2025年第1期46卷 315-321页

作者：童强肖帅磊姜宇董秀萍庞桂兵大连工业大学机械工程与自动化学院辽宁大连116034 海洋食品加工与安全控制全国重点实验室国家海洋食品工程技术研究中心辽宁省海产品精深加工产业共性技术创新平台大连市中式预制食品技术创新中心辽宁大连116034 大连工业大学食品交叉科学研究院辽宁大连116034

随着食品3D打印技术的快速发展,各种辅助技术与其结合的创新应用越来越受关注。激光技术具有精确、高能量和快速实现材料成型等特点,与食品3D打印技术的个性化定制优势高度契合,两者的结合在食品加工领域展现出巨大的应用前景。本文在... 详细信息

随着食品3D打印技术的快速发展,各种辅助技术与其结合的创新应用越来越受关注。激光技术具有精确、高能量和快速实现材料成型等特点,与食品3D打印技术的个性化定制优势高度契合,两者的结合在食品加工领域展现出巨大的应用前景。本文在介绍食品3D打印技术和激光技术发展现状的基础上,着重阐述激光技术在食品3D打印中的应用,包括激光参数(如波长、功率、脉冲等)和工艺优势。同时,指出激光技术在食品3D打印应用中所面临的挑战,如激光照射下的食品安全、应用局限等问题。最后,对激光技术和食品3D打印技术深度融合的发展趋势进行总结与展望,指明未来发展方向,为激光技术在食品3D打印领域的创新应用提供理论参考。

关键词：食品3D打印增材制造激光技术食品加工

From fundamental theory to realistic modeling of the birth of solar eruptions

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Science China Earth Sciences 2024年第12期67卷 3765-3788页

作者： Chaowei jiang Shenzhen Key Laboratory of Numerical Prediction for Space Storm Harbin Institute of TechnologyShenzhen 518055China

Solar eruptions,primarily manifested as solar flares,filament eruptions and coronal mass ejections,represent explosive releases of magnetic energy stored in the solar corona,with the potential to drive severe space *** initiation of solar eruptions remains an open question,leading to various theoretical models that are inferred from ***,these models are subjects of debate due to the absence of direct measurements of the three-dimensional(3D)magnetic fields in the *** simulations,based on solving magnetohydrodynamics(MHD)equations that govern the macroscopic dynamics of solar corona,serve as a touchstone for testing these theoretical *** early proposed model suggested that eruptions could be triggered by reconnection within a single sheared magnetic arcade,which is known as the tether-cutting reconnection model,but it was never confirmed through 3D MHD simulations until very ***,two models have gained more popularity:one involving the eruption of a twisted magnetic flux rope(MFR)due to ideal instability(or loss of equilibrium),and the other known as the breakout eruption,which requires a quadrupolar configuration with a delicately located magnetic null *** mixed mechanisms,involving both ideal instability and reconnection,are also proposed in association with localized magnetic flux *** with the validation of the tether-cutting model,the fundamental mechanisms are boiled down to two types of models,one primarily based on the ideal instability of a pre-existing MFR,and the other based on the reconnection of sheared field lines with or without an ***,the modelling of the birth of solar eruption using observed data-based MHD simulations has advanced rapidly,becoming a crucial research tool in the study of the initiation *** realistic modellings reveal a higher level of complexity compared to all currently available theories and idealized models.

关键词： Solar flares Coronal mass ejections Magnetohydrodynamics Numerical simulations Magnetic fields