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The Martingale Hardy Type Inequalities for Dyadic Derivative and Integral

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Acta Mathematica Sinica,English Series 2005年第6期21卷 1465-1474页

作者： JianYingnie Xing guo nie guo Wei LOU Institute of Near Sensing Technique with Millimeter Wave & Optical Wave Nanjing University of Science ~ Technology Nanjing 210094 P. R. China

Since the Leibniz-Newton formula for derivatives cannot be used in local fields, it is important to investigate the new concept of derivatives in Walsh-analysis, or harmonic analysis on local fields. On the basis of idea of derivatives introduced by Butzer, Schipp and Wade, Weisz has proved that the maximal operators of the one-dimensional dyadic derivative and integral are bounded from the dyadic Hardy space Hp,q to Lp,q, of weak type （L1,L1）, and the corresponding maximal operators of the two-dimensional case are of weak type （Hi, L1）. In this paper, we show that these maximal operators are bounded both on the dyadic Hardy spaces Hp and the hybrid Hardy spaces H^#p 0〈p≤1.

关键词： martingale Hardy space dyadic derivative dyadic integral Walsh-Fejer kernels p-atom,quasi-local operator

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大跨斜腿钢管桁架结构日照非均匀温度场研究

工程力学 2024年第1期41卷 208-218页

作者：王锦涛刘宇飞樊健生周勐聂建国强安鹏周照飞中南大学土木工程学院湖南长沙410075 清华大学土木工程系北京100084 中交第四公路工程局有限公司北京100102

大跨空间结构在施工过程中由于长期暴露在太阳辐射中,结构中存在明显的温度效应。又因为结构独特的空间网架特性以及太阳辐射角度的实时变化,杆件之间存在明显的遮挡作用,因此结构的温度场不仅是随时间变化的,还具有不均匀的特征。该文... 详细信息

大跨空间结构在施工过程中由于长期暴露在太阳辐射中,结构中存在明显的温度效应。又因为结构独特的空间网架特性以及太阳辐射角度的实时变化,杆件之间存在明显的遮挡作用,因此结构的温度场不仅是随时间变化的,还具有不均匀的特征。该文基于地理气象信息和杆件遮挡作用的结构温度场分析算法,以某个大跨斜腿钢管桁架结构为研究背景,模拟分析了结构的瞬态温度场,并结合结构的温度和微应变长期监测,对结构的不均匀温度场以及施工阶段受力进行了讨论。计算与实测结果表明,遮挡作用使得杆件之间的瞬态温差最大可达21%,时变性与不均匀性非常显著;结构施工阶段的受力主要来源于温度效应,结构在施工阶段的温度效应不可忽略。

关键词：大跨空间结构太阳辐射日照阴影温度效应长期监测

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Dynamically Computing Approximate Frequency Counts in Sliding Window over Data Stream

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 283-288页

作者： nie guo-liang LU Zheng-ding School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074Hubei China

This paper presents two one-pass algorithms for dynamically computing frequency counts in sliding window over a data stream-computing frequency counts exceeding user-specified threshold ε. The first algorithm constructs subwindows and deletes expired sub-windows periodically in sliding window, and each sub-window maintains a summary data structure. The first algorithm outputs at most 1/ε ＋ 1 elements for frequency queries over the most recent N elements. The second algorithm adapts multiple levels method to deal with data stream. Once the sketch of the most recent N elements has been constructed, the second algorithm can provides the answers to the frequency queries over the most recent n （ n≤N） elements. The second algorithm outputs at most 1/ε ＋ 2 elements. The analytical and experimental results show that our algorithms are accurate and effective.

关键词： data stream sliding window approximation algorithms frequency counts

The Electronic Structure and Formation Energies of Ni-doped CuAlO2 by Density Functional Theory Calculation

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Chinese Physics Letters 2014年第3期31卷 118-121页

作者： XU Ying LI Fei SHENG Wei nie guo-Zheng YUAN Ding-Wang School of Physics Hunan University of Science and Technology Xiangtan 411202 Department of Education Science Hunan First Normal University Changsha 410205 College of Materials Science and Engineering Hunan University Changsha 410082

The electronic structure and formation energies of Ni-doped CuAlO2 are calculated by first-principles calculations. Our results show that Ni is good for p-type doping in CuAlO2. When Ni is doped into CuAlO2, it prefers to substitute Al-site. NiAl is a shallow acceptor, while NiCu is a deep acceptor and its formation energy is high. Further electronic structure calculations show that strong hybridization happens between Ni-3d and O-2p states for Ni substituting Al-site, while localized Ni-3d states are found for Ni substituting Cu-site.

关键词： Density functional theory

Fluid-structure interaction simulation for multi-body flexible morphing structures

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Chinese Journal of Aeronautics 2024年第2期37卷 137-147页

作者： Wenzhi guo Yongtao SHUI Lu nie Gang CHEN State Key Laboratory of Strength and Vibration for Mechanic Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China China Academy of Launch Vehicle Technology Beijing 100076China China Academy of Aerospace Science and Innovation Beijing 100086China Shannxi Key Laboratory of Service Environment and Control for Flight Vehicles Xi’an Jiaotong UniversityXi’an 710049China

The multi-body flexible morphing airfoil can improve the aerodynamic characteristics based on different flight missions *** researches have focused on the unsteady aerodynamic characteristics of flexible wings under passive ***,the unsteady aerodynamic characteristics with the fluid-structure interaction effects in the multi-body active actuation process of morphing airfoil deserve further *** this paper,a fluid-structure coupled simulation method for multi-body flexible morphing airfoil with active actuation subsystem was investigated,and the aerodynamic characteristics during deformation were compared with different skin flexibility,flow field environment,actuation mode and actuation *** numerical results show that for the steady aerodynamic,the skin flexibility can improve the stability *** the unsteady process,the change trend of the transient lift coefficient and pitching moment are consistent with those of the active drive characteristics,while the instantaneous lift-drag ratio coefficient is greatly affected by the driving mode and can be improved by increasing the driving duration.

关键词： Fluid-structure interaction Multi-body dynamics modeling Flexible structures Aerodynamics Morphing wings

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废旧轮胎裂解炭黑梯度温度的研究

广州化工 2024年第11期52卷 20-22页

作者：钟锶灿黄家锵聂国朝玉林师范学院化学与食品科学学院广西玉林537000 玉林师范学院物理与电信工程学院广西玉林537000 广西绿循环新材料技术有限责任公司广西玉林537006

随着私家车的市场需求不断增大,轮胎的需求量在不断增加,同时伴随着废旧轮胎废弃量在不断增加,传统处理废旧轮胎的方法会带来严重的大气污染,不利用保护环境。在研究轮胎的成分实验中,发现废旧轮胎经过一次裂解能够得到粗炭黑,二次加工... 详细信息

随着私家车的市场需求不断增大,轮胎的需求量在不断增加,同时伴随着废旧轮胎废弃量在不断增加,传统处理废旧轮胎的方法会带来严重的大气污染,不利用保护环境。在研究轮胎的成分实验中,发现废旧轮胎经过一次裂解能够得到粗炭黑,二次加工能够得到经济价值较高的纳米多功能炭黑。据本实验数据分析,粗炭黑在不同的温度下裂解得到的产物是不一样的,此外同一温度下裂解时间不同得到的产物也是大不相同。本研究旨在研究废旧轮胎在不同温度以及在不同裂解时间下得到的产物,进而得出废旧轮胎裂解炭黑的较佳的温度和裂解时间。本实验仅研究废旧轮胎一次高温裂解得到的产物。

关键词：废旧轮胎梯度裂解炭黑一次裂解橡胶制品

基于APCS-MLR受体模型的弹药销毁场土壤重金属源解析

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环境化学 2024年第7期43卷 2313-2324页

作者：毕永顺朱勇兵刘祖文赵三平张言聂果郇正来田帅左华伟江西理工大学赣州市流域污染模拟与控制重点实验室赣州341000 国民核生化灾害防护国家重点实验室北京102205 南昌工程学院水利与生态工程学院南昌330099

为了掌握弹药销毁场重金属污染状况与来源,以山西某典型弹药销毁场为例,对该销毁场39个表层土壤重金属(Cr、Ni、Cu、Zn、As、Cd、Sb、Pb)的污染状况、分布特征与污染来源进行评价与分析.结果表明,弹壳堆放区表层土壤重金属Cr、Ni、Cu、Z... 详细信息

为了掌握弹药销毁场重金属污染状况与来源,以山西某典型弹药销毁场为例,对该销毁场39个表层土壤重金属(Cr、Ni、Cu、Zn、As、Cd、Sb、Pb)的污染状况、分布特征与污染来源进行评价与分析.结果表明,弹壳堆放区表层土壤重金属Cr、Ni、Cu、Zn、As、Cd、Sb、Pb的平均含量分别为45.57、23.43、325.54、265.43、9.53、0.42、304.17、13174.29 mg·kg^(-1),其余区域表层土壤重金属Cr、Ni、Cu、Zn、As、Cd、Sb、Pb的平均含量分别为102.09、26.75、1137.18、3007.13、7.71、0.95、70.65、2894.97 mg·kg^(-1),均高于山西省背景值.污染指数评价结果表明,Pb、Zn、Cu、Sb和Cd的累积程度较高.研究区土壤重金属生态危害指数为2653.35,达到极高生态风险水平.绝对主成分得分-多元线性回归模型(APCS-MLR)表明,Ni、Cd、Zn、Cr和Cu的来源主要为混合源,贡献率为72.94%,Pb和Sb的主要来源是销毁源,贡献率为53.99%,自然源对As贡献率最大,为44.63%.

关键词：弹药销毁场重金属污染特征潜在生态风险 APCS-MLR受体模型

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Influence of Organic Amendments on Adsorption, Desorption and Leaching of Methiopyrisulfuron in Soils

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Journal of Integrative Agriculture 2013年第9期12卷 1589-1597页

作者： WU Chun-xian nie guo ZHANG Zhong-ming WANG Guang-cheng GAO Li-ming WANG Jin-jun College of Plant Protection Southwest University Institute of the Control of Agrochemical of Sichuan Province

Methiopyrisulfuron is a novel sulfonylurea herbicide with good activity for annual broadleaf and gramineal weeds control. Present study was to investigate the effects of organic amendments （including peat （PE）, sewage sludge （SS）, and humic acid （HA）） on adsorption, desorption and leaching of methiopyrisulfuron in soils. The batch equilibration technique was applied for adsorption-desorption experiments and the leaching was tested through soil column simulated experiments under laboratory conditions. The Freundlich model may well describe adsorption-desorption of methiopyrisulfuron on organic amendments, the natural soil, and amended soils. Organic amendments could not only greatly increase the adsorption capacity of methiopyrisulfuron, but also significantly enhance the hysteresis of desorption of methiopyrisulfuron. The correlations between Kf_ads and organic matter content of amended soils were significant, and the correlations between H and soil organic matter in amended soils with PE, SS, and HA were significant too. The results of soil column experiments indicated that organic amendments greatly decreased leaching of methiopyrisulfuron. This study suggested that PE, SS, and HA could greatly influence environmental behavior of methiopyrisulfuron in soils. Use of organic amendments might be an effective management practice for controlling potential pollution of methiopyrisulfuron to environment.

关键词： organic amendment adsorption desorption leaching methiopyrisulfuron soil

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放大工装及响应谱控制在振动试验中的应用

机械研究与应用 2024年第4期37卷 184-186页

作者：喻琴聂国柱赵玉杰金江波庆安集团有限公司航空设备研究所陕西西安710077

某安装于飞机作动筒内的传感器振动量值约为130 g,超过了振动台额定量级。文章灵活利用振动工装的传递特性,设计了具有放大作用的工装,使振动台的输出量级放大并传递给试验件,以达到振动台低输出而试验件高量级振动的理想效果。然后,搭... 详细信息

某安装于飞机作动筒内的传感器振动量值约为130 g,超过了振动台额定量级。文章灵活利用振动工装的传递特性,设计了具有放大作用的工装,使振动台的输出量级放大并传递给试验件,以达到振动台低输出而试验件高量级振动的理想效果。然后,搭建了振动试验系统,运用加速度响应控制方法成功完成了位移传感器高量值持续14 h的振动耐久环境试验。仿真与试验结果表明:该工装的设计达到既定的放大设计要求。

关键词：位移传感器振动试验放大工装响应谱控制