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GENERALIZED p-VALUES AND GENERALIZED CONFIDENCE INTERVALS FOR VARIANCE COMPONENTS IN GENERAL RANDOM EFFECT MODEL WITH BALANCED DATA

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Journal of Systems Science & Complexity 2007年第4期20卷 572-584页

作者： Rendao ye Songgui WANG College of Applied Sciences Beijing University of Technology Beijing 100022 China

Various random models with balanced data that are relevant for analyzing practical test data are described, along with several hypothesis testing and interval estimation problems concerning variance components. In this paper, we mainly consider these problems in general random effect model with balanced data. Exact tests and confidence intervals for a single variance component corresponding to random effect are developed by using generalized p-values and generalized confidence intervals. The resulting procedures are easy to compute and are applicable to small samples. Exact tests and confidence intervals are also established for comparing the random-effects variance components and the sum of random-effects variance components in two independent general random effect models with balanced data. Furthermore, we investigate the statistical properties of the resulting tests. Finally, some simulation results on the type Ⅰ error probability and power of the proposed test are reported. The simulation results indicate that exact test is extremely satisfactory for controlling type Ⅰ error probability.

关键词： Generalized confidence interval generalized p-value variance component.

紫外辐照对自润滑关节轴承衬垫磨损性能的影响

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中国表面工程 2024年第3期37卷 134-144页

作者：叶强谭德强宗法涛胡月贺强杨文锋周长春中国民用航空飞行学院航空工程学院广汉618307

PTFE/Kevlar织物材料具有优异自润滑性能,在航空关键部件中广泛应用,但紫外辐照对其影响规律尚不清晰。针对航空器飞行强紫外线暴露的特点,聚焦紫外辐照对航空常用PTFE/Kevlar编织关节轴承衬垫自润滑材料摩擦学性能的影响规律研究。对... 详细信息

PTFE/Kevlar织物材料具有优异自润滑性能,在航空关键部件中广泛应用,但紫外辐照对其影响规律尚不清晰。针对航空器飞行强紫外线暴露的特点,聚焦紫外辐照对航空常用PTFE/Kevlar编织关节轴承衬垫自润滑材料摩擦学性能的影响规律研究。对不同紫外辐照时长的PTFE/Kevlar织物衬垫材料进行往复摩擦试验,并采用多种表征手段对其宏观、微观损伤形貌以及化学状态进行分析。结果表明:PTFE/Kevlar织物衬垫材料的磨损程度随着紫外辐照时间的增加呈现出先降低后升高的趋势,短时辐照(T=100 h和200 h)的磨损最轻微,摩擦损失体积和磨痕最大深度仅为未辐照和长时辐照(T=300 h和500h)的2/3;紫外辐照后,衬垫材料与GCr15轴承钢球之间的磨损行为变化表现为PTFE纤维塑性变形和转移膜形成能力的下降,其主要原因是PTFE纤维结晶度的降低;衬垫材料的磨损机理随辐照时间的延长由疲劳磨损和粘着磨损向磨粒磨损为主转变。研究成果可为PTFE/Kevlar织物衬垫型自润滑材料在紫外辐照后的磨损性能跟踪和研制优化提供参考。

关键词： PTFE/Kevlar织物紫外辐照损伤形貌转移膜磨损机理

一种基于条纹相位特征的印刷电路板三维重建方法

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光学学报 2024年第14期44卷 144-153页

作者：吴福培彭俊龙叶玮琳郑志丹李昇平汕头大学工学院机械工程系广东汕头515063

重建印刷电路板(PCB)表面元器件的三维形貌对确保其贴装质量具有重要意义。为提升PCB表面三维重建的精度和可靠性,本文提出了一种基于条纹相位特征的PCB三维重建方法。首先,基于自适应权重法建立多曝光图像的融合规则,进而合成高质量的... 详细信息

重建印刷电路板(PCB)表面元器件的三维形貌对确保其贴装质量具有重要意义。为提升PCB表面三维重建的精度和可靠性,本文提出了一种基于条纹相位特征的PCB三维重建方法。首先,基于自适应权重法建立多曝光图像的融合规则,进而合成高质量的条纹图像,并构建异步多频相移法以求解视场内各像素点的相位值;其次,针对结构光三角立体模型因标定误差而影响PCB重建精度的问题,由相机和结构光发生器视线映射关系建立高度重建模型;在此基础上,基于标准量块的测量值标定并拟合出最终的三维重建参数。实验结果表明,所提方法可有效提升高动态范围复杂表面的三维重建效果;在精度评价实验中,采用所提三维重建方法测量陶瓷标准球的平均直径误差为0.0188 mm,且能准确可靠地恢复PCB表面元器件的三维形貌,进一步检验了所提方法的有效性。

关键词：三维重建条纹结构光印刷电路板参数标定图像融合

A dimensional analysis on asphalt binder fracture and fatigue cracking

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Frontiers of Structural and Civil Engineering 2018年第2期12卷 201-206页

作者： Qian ZHAO Zhoujing ye National Center for Materials Service Safety University of Science and Technology Beijing Beijing 100083 China

Fracture and fatigue cracking in asphalt binder are two of most serious problems for pavement engineers. In this paper, we present a new comprehensive approach, which consists both of dimensional analysis using Buckingham H Theorem and J-integral analysis based on classic fracture mechanics, to evaluate the fracture and fatigue on asphalt binder. It is discovered that the dimensional analysis could provide a new perspective to analyze the asphalt fracture and fatigue cracking mechanism.

关键词： Dimensional analysis asphalt fracture fatigue cracking

Synthesis,Growth Mechanism,and Applications of Zinc Oxide Nanomaterials

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Journal of Materials Science & Technology 2008年第4期24卷 457-472页

作者： Shulin JI Changhui ye Anhui Key Laboratory of Nanomaterials and Technology and Key Laboratory of Materials Physics Institute of SolidState Physics Chinese Academy of Sciences Hefei 230031 China

This article reviews recent progresses in growth mechanism, synthesis, and applications of zinc oxide nano-materials （mainly focusing on one-dimensional （1D） nanomaterials）. In the first part of this article, we briefly introduce the importance, the synthesis methods and growth mechanisms, the properties and applications of ZnO 1D nanomaterials. In the second part of this article, the growth mechanisms of ZnO 1D nanomaterials will be discussed in detail in the framework of vapor-liquid-solid （VLS）, vapor-solid （VS）, and aqueous solution growth （ASG） approaches. Both qualitative and quantitative information will be provided to show how a controlled synthesis of ZnO 1D nanomaterials can be achieved. In the third part of this article, we present recent progresses in our group for the synthesis of ZnO 1D nanomaterials, and the results from other groups will only be mentioned briefly. Especially, experiment designing according to theories will be elaborated to demonstrate the concept of controlled synthesis. In the fourth part of this article, the properties and potential applications of ZnO 1D nanomaterials will be treated. Finally, a summary part will be presented in the fifth section. The future trend of research for ZnO 1D nanomaterials will be pointed out and key issues to be solved will be proposed.

关键词： Zinc Oxide One-dimensional Nanomaterials Controlled synthesis

Solution-phase Synthesis of One-dimensional Semiconductor Nanostructures

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Journal of Materials Science & Technology 2008年第4期24卷 529-540页

作者： Jianfen. ye Limin QI Beijing National Laboratory for Molecular Sciences （BNLMS） State Key Laboratory for Structural Chemistry of Unstable and Stable Species College of Chemistry Peking University Beijing 100871 China

The synthesis of one-dimensional （1D） semiconductor nanostructures has been studied intensively for a wide range of materials due to their unique structural and physical properties and promising potential for future technological applications. Among various strategies for synthesizing 1D semiconductor nanostructures, solution-phase synthetic routes are advantageous in terms of cost, throughput, modulation of composition, and the potential for large-scale and environmentally benign production. This article gives a concise review on the recent developments in the solution-phase synthesis of ID semiconductor nanostructures of different compositions, sizes, shapes, and architectures. We first introduce several typical solution-phase synthetic routes based on controlled precipitation from homogeneous solutions, including hydrothermal/solvothermal process, solution-liquid-solid （SLS） process, high-temperature organic-solution process, and low-temperature aqueous-solution process. Subsequently, we discuss two solution-phase synthetic strategies involving solid tem- plates or substrates, such as the chemical transformation of 1D sacrificial templates and the oriented growth of 1D nanostructure arrays on solid substrates. Finally, prospects of the solution-phase approaches to 1D semiconductor nanostructures will be briefly discussed.

关键词： Solution-phase synthesis One-dimensional Nanostructures Semiconductor

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动态有权图上的随机游走概率计算

计算机研究与发展 2024年第8期61卷 1865-1881页

作者：王涵之易璐魏哲巍甘骏豪袁野文继荣杜小勇中国人民大学信息学院北京100872 中国人民大学高瓴人工智能学院北京100872 琶洲实验室(黄埔) 广州510555 墨尔本大学澳大利亚墨尔本VIC3010 北京理工大学计算机学院北京100081 大数据管理与分析方法研究北京市重点实验室(中国人民大学高瓴人工智能学院) 北京100872 数据工程与知识工程教育部重点实验室(中国人民大学) 北京100872

图上的随机游走概率计算是传统图论与现代数据挖掘领域普遍关注的问题之一.现有工作普遍关注静态图上的随机游走概率计算,却鲜少关注与实际应用场景更贴合的权重动态图.针对动态有权图上的随机游走概率计算问题,提出了一种基于硬币翻转... 详细信息

图上的随机游走概率计算是传统图论与现代数据挖掘领域普遍关注的问题之一.现有工作普遍关注静态图上的随机游走概率计算,却鲜少关注与实际应用场景更贴合的权重动态图.针对动态有权图上的随机游走概率计算问题,提出了一种基于硬币翻转采样的随机游走概率计算方法.相比于传统的基于权重采样的随机游走概率计算方法,所提方法可以在保证随机游走概率计算结果无偏的前提下,同时做到近似最优的随机游走概率计算复杂度和最优的采样结构更新复杂度.作为对比,现有方法或具有较大的计算时间复杂度,或依赖于复杂的索引结构而难以在动态图上即时更新.对所提方法做出了详细的理论分析,并在真实图数据集上进行模拟实验,实验结果证实了所提方法的有效性.

关键词：随机游走概率计算动态有权图硬币翻转采样实时更新大规模图

The influence of Cretaceous paleolatitude variation of the Tethyan Himalaya on the India-Asia collision pattern

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Science China Earth Sciences 2017年第6期60卷 1057-1066页

作者： ZHANG ye HUANG BaoChun Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University Beijing 100871 China

Identifying when, where, and how India and Asia collided is a prerequisite to better understand the evolution of the Himalayan-Tibetan Plateau. Whereas with essentially the same published paleomagnetic data, a large range of different India-Asia collision models have been proposed in the literature. Based upon the premise of a northwards-moving Indian plate during the Cretaceous times, we analyze the significant variations in relative paleolatitude produced by a nearly 90° counterclockwise(CCW)rotation of the plate itself during the Cretaceous. Interestingly, recent studies proposed a dual-collision process with a Greater India basin or post-Neo-Tethyan ocean for the India-Asia collision, mainly in the light of divergent Cretaceous paleolatitude differences of the Tethyan Himalaya between the observed values and expected ones computed from the apparent polar wander path of the Indian plate. However, we find that these varied paleolatitude differences are mainly resulted from a nearly 90° CCW rotation of a rigid/quasi-rigid Greater Indian plate during the Cretaceous. On the other hand, when the Indian craton and Tethyan Himalaya moved as two individual blocks rather than a united rigid/quasi-rigid Greater Indian plate before the India-Asia collision, current available Cretaceous paleomagnetic data permit only multiple paleogeographic solutions for the tectonic relationship between the Indian plate and the Tethyan Himalayan terrane. We therefore argue that the tectonic relationship between the Indian plate and the Tethyan Himalayan terrane cannot be uniquely constrained by current paleomagnetic data in the absence of sufficient geological evidence, and the so-called Greater India basin model is just one of the ideal scenarios.

关键词： India-Asia collision model Tethyan Himalaya Apparent polar wander (APW) path Paleolatimde Vertical-axis rotation

中红外涡旋激光在有机晶体DSTMS中的演化(特邀)

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光学学报 2024年第10期44卷 307-313页

作者：林婷孟宪泽郑卓锐丁营营宋立伟刘一田野上海理工大学光电信息与计算机工程学院上海200093 中国科学院上海光学精密机械研究所强场激光物理国家重点实验室上海201800

具有轨道角动量的涡旋光束相比其他光束有很多独特的性质,其螺旋状的波前结构和相位变化为诸多应用开辟了新的维度。对涡旋光在非线性有机晶体DSTMS中的传输演化机制进行实验研究,探索了涡旋中红外激光的非线性传输特性,利用广义高斯光... 详细信息

具有轨道角动量的涡旋光束相比其他光束有很多独特的性质,其螺旋状的波前结构和相位变化为诸多应用开辟了新的维度。对涡旋光在非线性有机晶体DSTMS中的传输演化机制进行实验研究,探索了涡旋中红外激光的非线性传输特性,利用广义高斯光束分解方法模拟分析了拉盖尔-高斯光束经过介质前后的光强分布,并对比了不同入射涡旋光的偏振态对出射光斑的影响的差异。

关键词：物理光学涡旋光束五阶非线性 DSTMS晶体偏振