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Mean-square estimate of automorphic L-functions

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Frontiers of Mathematics in China 2020年第1期15卷 205-213页

作者： Weili yao Department of Mathematics Shanghai UniversityShanghai 200444China

Let f be a holomorphic Hecke cusp form with even integral weight k≥2 for the full modular group,and letχbe a primitive Dirichlet character modulo *** Lf(s,χ)be the automorphic L-function attached to f andχ-We stud... 详细信息

关键词： Automorphic L-function cusp form Fourier coefficient

Why Can We Copy Classical Information？

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Chinese Physics Letters 2011年第1期28卷 30-31页

作者： SHEN yao Key Laboratory for Atomic and Molecular Nanosciences and Department of Physics Tsinghua University Beijing 100084 Tsinghua National Laboratory for Information Science and Technology Tsinghlza University Beijing 100084

It is pointed out that the noneloning theorem in quantum mechanics also holds for unknown state in linear classical physics. The apparent capability of copying of a classical state is essentially the capability of perfect measurement in classical physics. The difference in copying- between quantum and classical physics is the difference in measurement between the two theories. A classical copying process is the combined action of measurement of an unknown state and the preparation of this state onto another system. Hence perfect measurability in classical physics enables the copying of a classical state.

关键词： Physics Measurement

Self-adjustment of Carrying Capacity of Concrete Embedded with CFRC

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Journal of Materials Science & Technology 2006年第3期22卷 401-403页

作者： Wu yao School of Materials Science and Engineering Tongji University Shanghai 200092 China

By heating up the embedded carbon fiber reinforced cement based material （CFRC）, the carrying capacity and deformation of concrete member could be adjusted. The relationship between temperature difference and expansion strain of CFRC was demonstrated, and the temperature-deformation-load effect of concrete embedded with CFRC was studied. Heating the CFRC up to different temperatures resulted in different degree of inner pre-stress in concrete. Thus, the load capacity of concrete could be regulated owing to counteracting the pre-stress.

关键词： Carbon fiber Self-adjustment Concrete Pre-stress

Crystal plasticity model to predict fatigue crack nucleation based on the phase transformation theory

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Acta Mechanica Sinica 2019年第5期35卷 1033-1043页

作者： Lu Liu Jundong Wang Tao Zeng yao yao School of Mechanics Civil Engineering and ArchitectureNorthwestern PolytechnicalUniversityXi'an 710072China Max-Planck-Institut für Eisenforschung GmbH Max Planck Str.140237 DüsseldorfGermany

A crystal plasticity model is developed to predict the fatigue crack nucleation of polycrystalline materials,in which the accumulated dislocation dipoles are considered to be the origin of *** describe the overall softening behavior under cyclic loading,a slip system-level dislocation density-related damage model is proposed and implemented in the finite element analysis with Voronoi *** numerical model is applied to calibrate the stress-strain relationship at different cycles before fatigue crack *** parameters determined from the numerical analysis are substituted into a modified phase transformation model to predict the critical fatigue crack nucleation *** with the experimental results of Sn-3.0Ag-0.5Cu(SAC305)alloy and P91 steel,the proposed method can describe the constitutive behavior and predict the fatigue crack nucleation accurately.

关键词： Fatigue crack nucleation Damage Crystal plasticity Finite element Dislocation density

Experimental Study on Preheated Combustion of Pulverized Semi-coke

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Journal of Thermal Science 2015年第4期24卷 370-377页

作者： yao yao ZHU Jianguo LU Qinggang ZHOU Zuxu University of Chinese Academy of Sciences Institute of Engineering Thermophysics Chinese Academy of Sciences

In a test rig,pulverized semi-coke was preheated to 850℃in a circulating fluidized bed(CFB)and then cornbusted at 1100℃in a down-fired combustor(DFC).Experiments were conducted to reveal the effects of three secondary air nozzle cases(co-axial jet,top circular jet and wall circular jet)on the NO *** results show that the optimized secondary air nozzle can reduce NO emission.O_2 concentration profile is the major factor affecting NO generation and emission,which is led by the secondary air *** lower O_2 concentration led to the generation of lower initial *** NO emission at the exit of the DFC was reduced from 189 to 92mg/m^3(@6%O_2)with the decrease of initial *** peak of NO at 100 mm below the nozzle should be attributed to the oxidization of NH_3 in the syngas,rather than the oxidization of fuel-N in the *** low and well-distributed O_2 concentration contributes to the reduction of initial NO,which helps to reduce the NO *** combustion effieiencies of the eases of the co-axial jet,the top circular jet,and the wall circular jet are97.88%,98.94%and 98.74%,respectively.

关键词： Pulverized semi-coke Preheated combustion Secondary air nozzle NO emission.

An upgraded scheme of surface physics for Antarctic ice sheet and its implementation in the WRF model

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Science Bulletin 2016年第7期61卷 576-584页

作者： yao yao Jianbin Huang Yong Luo Zongci Zhao Ministry of Education Key Laboratory for Earth System Modeling Center for Earth System Science and Joint Center for Global Change Studies Tsinghua University

Regional climate models often lack detailed description of ice sheet surface and, as a result, are limited in their capability to provide useful information for Antarctic climate research and field campaigns. In this study, an upgraded scheme of surface physics for Antarctic ice sheet(IST) is developed to improve the surface temperature simulations in Antarctica. Through stand-alone simulations, IST shows advantages over the Noah glacial module, a commonly utilized scheme in the widely used Weather Research and Forecasting(WRF) model. These improvements are mainly attributed to the incorporation of detailed snow physics and optimized surface layer parameterization, which results in better simulations of both the surface albedo in summer and the turbulent sensible heat flux in winter. When coupled with IST instead of Noah,WRF models show improved simulation of surface temperatures throughout the year. The bias and root-meansquare-error of annual mean surface temperatures are reduced from 5.7 and 6.0 to 0.2 and 2.7 K.

关键词： Regional climate model Antarctica Surface temperature Ice sheet

A Survey on Pre-Processing in Image Matting

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Journal of Computer Science & Technology 2017年第1期32卷 122-138页

作者： Gui-Lin yao School of Computer and Information Engineering Harbin University of Commerce Harbin 150028 China

Pre-processing is an important step in digital image matting, which aims to classify more accurate foreground and background pixels from the unknown region of the input three-region mask （Trimap）. This step has no relation with the well-known matting equation and only compares color differences between the current unknown pixel and those known pixels. These newly classified pure pixels are then fed to the matting process as samples to improve the quality of the final matte. However, in the research field of image matting, the importance of pre-processing step is still blurry. Moreover, there are no corresponding review articles for this step, and the quantitative comparison of Trimap and alpha mattes after this step still remains unsolved. In this paper, the necessity and the importance of pre-processing step in image matting are firstly discussed in details. Next, current pre-processing methods are introduced by using the following two categories： static thresholding methods and dynamic thresholding methods. Analyses and experimental results show that static thresholding methods, especially the most popular iterative method, can make accurate pixel classifications in those general Trimaps with relatively fewer unknown pixels. However, in a much larger Trimap, there methods are limited by the conservative color and spatial thresholds. In contrast, dynamic thresholding methods can make much aggressive classifications on much difficult cases, but still strongly suffer from noises and false classifications. In addition, the sharp boundary detector is further discussed as a prior of pure pixels. Finally, summaries and a more effective approach are presented for pre-processing compared with the existing methods.

关键词： image matting pixel classification pre-processing Trimap expansion

地铁曲线地段扣件刚度对钢轨波磨的影响实测与仿真分析

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山西建筑 2025年第1期51卷 129-133页

作者：姚宇飞中铁第一勘察设计院集团有限公司陕西西安710043

钢轨波磨是地铁典型病害之一。为抑制钢轨波磨的产生,对某地铁线路的钢轨波磨特征、轨道刚度进行测试,并基于摩擦自激振动理论,研究了扣件刚度对钢轨波磨的影响。结合实测与仿真结果,提出了钢轨波磨控制措施,并通过后续测试对治理效果... 详细信息

钢轨波磨是地铁典型病害之一。为抑制钢轨波磨的产生,对某地铁线路的钢轨波磨特征、轨道刚度进行测试,并基于摩擦自激振动理论,研究了扣件刚度对钢轨波磨的影响。结合实测与仿真结果,提出了钢轨波磨控制措施,并通过后续测试对治理效果进行评价。研究结果表明:该线路存在40 mm~60 mm典型波长的钢轨波磨,并且内轨钢轨波磨更为严重。轮轨系统的不稳定振动主要发生在内侧轮轨之间,且频率为445.38 Hz。增大扣件垂、横向刚度可以抑制该不稳定振动,降低轨道结构在400 Hz, 800 Hz频率下的动态响应。波磨治理1年后,内外轨的不平顺幅值并未有明显增长,钢轨波磨发展速度得到明显控制。研究结果可为既有线路钢轨波磨治理以及新建线路钢轨波磨预防提供参考。

关键词：地铁钢轨波磨扣件刚度现场测试仿真分析

不同倾角煤岩组合煤柱破坏规律及稳定性控制研究

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煤炭技术 2025年第1期44卷 88-92页

作者：姚士茂国能神东煤炭布尔台煤矿内蒙古鄂尔多斯017000

以神东某矿为研究背景,采用理论分析、模拟试验,模拟研究了不同倾角煤-岩组合体强度关系及损伤演化规律,研究了不同倾角组合煤岩体单轴压缩下力学特性及破坏特征,分析了组合体中煤-岩不同倾角交界面对其整体变形破坏的影响,提出了组合... 详细信息

以神东某矿为研究背景,采用理论分析、模拟试验,模拟研究了不同倾角煤-岩组合体强度关系及损伤演化规律,研究了不同倾角组合煤岩体单轴压缩下力学特性及破坏特征,分析了组合体中煤-岩不同倾角交界面对其整体变形破坏的影响,提出了组合体煤柱锚喷锚杆强化支护技术。结果表明:随着煤岩组合体倾角增加,峰值强度降低,应力-应变曲线线性行为发生时间变短。煤岩组合体产生滑移破坏分界为30°~40°;倾角越小,煤岩组合体加载过程中越难产生损伤,且产生损伤过程应变越大;反之,倾角越大,越容易发生损伤。倾角较小时,煤岩组合体受力过程中不易变形,且需要很大的加载力才能使煤岩组合体产生损伤破坏。所提组合体煤柱锚喷锚杆强化支护效果显著大于普通支护效果。通过对煤岩组合体损伤演化进行分析,可为现场监测及煤岩体失稳破坏前兆提供判据。

关键词：煤岩组合体失稳破坏力学特性损伤演化