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Journal of Thermal Science 2000年第1期9卷 23-29页

作者： Matthias Buschmann (Institute of Fluid Mechanics Dresden University of Technology

The paper Presents an analysis of two-dimensional zero pressure gradient (ZPG) turbulent boundary layers (TBL) with regard to the application of power laws. Only TBL with low Reynolds number 300 power law of the form u+ = Cpow * y+α This power law region is not a Priori identical with the overlap region. An algorithm for the determination of the wall skin friction using the power law is proposed. The method was applied with good result to ZPG TBL and to adverse pressure gradient (APG) TBL. To bridge the gap between the wall and the power law region an approach for the turbulent viscosity is suggested.

关键词： power law turbulent boundary layer scaling analysis fluid mechanics

Spatial estimation of wind speed:a new integrative model using inverse distance weighting and power law

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International Journal of Digital Earth 2016年第8期9卷 733-747页

作者： Emre Ozelkan Gang Chen Burak Berk Ustundag Agricultural&Environmental Informatics Research and Application Centre Istanbul Technical UniversityIstanbulTurkey Department of Geography and Earth Sciences University of North Carolina at CharlotteCharlotteNCUSA Laboratory for Remote Sensing and Environmental Change(LRSEC) University of North Carolina at CharlotteCharlotteNCUSA

Spatial interpolation(SI)is currently one of the most common ways to estimate wind speed(Ws).However,classic SI models either ignore the complex geography[*** distance weighting(IDW)],or demand high computational resources(***).This study aimed to develop a simple yet effective SI model for estimating Ws in Eastern Thrace of *** new method,named MIDW(Ws),is a modified IDW through the integration of IDW with wind profile model,power law(PL),representing the influence of land cover and topography on *** features and elevation data of PL were obtained using normalized difference vegetation index(NDVI)and digital elevation model(DEM),*** showed superior and comparable performance of MIDW(Ws)to standard IDW and ordinary kriging(OK)across all months of *** to ordinary cokriging(OCK)using DEM as covariate,MIDW(Ws)generated better results in the arid–semiarid seasons(around summer).Local complex atmospheric conditions during rainy seasons(around winter)may have affected the performance of incorporating PL with MIDW(Ws).Generally,the proposed MIDW(Ws)is simpler and easier to implement compared to *** landscape-scale projects,its high computational efficiency and relatively robust performance show potential to deal with large volumes of datasets.

关键词： Wind speed power law NDVI spatial interpolation modified inverse distance weighting

power law DISTRIBUTION AND SELF-ORGANIZED CRITICALITY OF DISPERSED PARTICLES

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China Particuology 2005年第4期3卷 237-239页

作者： Degang Ma Lihe Chai School of Environmental Science and Technology Tianjin University Tianjin 300072 P. R. China

Research on particulate characteristics has been an important frontier in physics and chemistry during the past decades. It has however been mostly focused on granular materials with short-range interactions. In this work, it was found that the power law of particle size distribution applied to the long-range interacting system of floating dust in air, from which we deduced that self-organized criticality might hold for floating dust just as granular materials with short-range interactions. This feature may reveal underlying kinetic mechanisms, important in dispersed particle systems. In industry, power law of size distribution of dispersed particles can be used to investigate the change of dust size, and the power law parameter could be taken as an important index for dust separation.

关键词： dispersed particle floating dust self-organized criticality power law

Failure analysis on China power grid based on power law

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控制理论与应用（英文版） 2006年第3期4卷 235-238页

作者： Xiaofeng WENG Yiguang HONG Ancheng XUE Shengwei MEI State Key Lab of power Systems Department of Electrical Engineering Tsinghua University Beijing 100084 China Institute of Systems Science Chinese Academy of Sciences Beijing 100080 China

This paper is concerned with the mechanism of blackouts in China power system from the viewpoint of self-organized criticality. By using two estimation algorithms of scaled window variance （SWV） and rescaled rangestatistics （R/S）, this paper studies the blackout data in China power system during 1988-1997. The result of analysis shows that the blackout data of 1994-1997 coincides well with the autocorrelation. Furthermore, it is found that the function of blackout probability vs. blackout size exhibits power law distribution.

关键词： power system Blackout power law Estimation algorithm

Towards Optimal Synchronization in power law Networks

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Towards Optimal Synchronization in Power Law Networks

Failure analysis on electric power system in our country based on power law

第25届中国控制会议

作者： Fan Jin, Wang Xiaofan, Li Xiang Department of Automation, Shanghai Jiao Tong University, Shanghai 200240

＜正＞In this paper, an edge rewiring mechanism is proposed to optimize the synchronizability of a power law network with keeping the degree of each vertex unchanged, and the network synchronizability after the novel optimal rewiring is enhanced. The rewiring mechanism is also found to reduce the characteristic path length and maximum between-ness centrality of the network.

关键词： Synchronization edge rewiring complex networks power law

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Failure analysis on electric power system in our country bas...

power law液体圆管螺旋流的解析解——速度分布、流量和压降梯度的计算公式

第二十三届中国控制会议

作者： Yiguang Hong Xiaofeng Weng Ancheng Xue Shengwei Mei (Institute of Systems Science, Chinese Academy of Sciences, Beijing 100080, China) (Department of Electrical Engineering, Tsinghua university, Beijing 100084, China)

This paper is to employ power law approach to discuss self-organized criticality and related dynamical features of power systems. We use two estimation algorithms called scaled window variance (SWV) and rescaled range statistical (R/S) to analyze the data of blackout events during 1988-1997 of power systems in China. From the analysis we found that the data from 1994 to 1997 show the autocorrelation of the blackouts vs. time lags. Moreover, we find the power law distribution in blackout probability vs. event size.

关键词： power systems Blackout power law Estimation aigoritnm

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东北石油大学学报 1987年第3期 132-137页

作者：崔海清王辛张海桥大庆石油学院数学教研室大庆石油学院水力学教研室

作者于1984年在理论上和实验上完成了泥浆常用的power law液体在环形空间中螺旋流动规律的研究。本文将完成该液体在钻柱内(圆管)的螺旋流动的理论研究。根据非牛顿流体力学原理,运用数学方法,给出了圆管层流螺旋流的视粘度分布、速度... 详细信息

作者于1984年在理论上和实验上完成了泥浆常用的power law液体在环形空间中螺旋流动规律的研究。本文将完成该液体在钻柱内(圆管)的螺旋流动的理论研究。根据非牛顿流体力学原理,运用数学方法,给出了圆管层流螺旋流的视粘度分布、速度分布和流量的解析表达式;进而建立了压降梯度的计算公式。

关键词：圆管金属管螺旋流动流体流动 power law 压降计算公式速度分布分布(力学) 解析解

Caching Scheme Based on power-law Characteristic in Unstructured P2P Networks

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Journal of Southwest Jiaotong University(English Edition) 2009年第3期17卷 177-184页

作者：左翠华李瑞轩卢正鼎 School of Computer Science and Technology Huazhong University of Science and Technology

In order to reduce the traffic load and improve the availability of the shared resources in unstructured P2P networks, a caching scheme combining alternative index and adaptive replication （AIAR） is presented. AIAR uses random walk mechanism to disperse the caching information of resources in the network based on its power-law characteristic, and dynamically adjusts replicas according to the visit frequency on resources and the degree information of peers. Subsequent experimental results show that the proposed AIAR scheme is beneficial to improve the search performance of success rate and respond speed. In addition, compared to some existing caching scheme, AIAR can perform much better in success rate, especially in a dynamic environment.

关键词： P2P (peer-to-peer) Caching scheme Replication Random walk power law

The Equilibrium of Fractional Derivative and Second Derivative: The Mechanics of a power-law Visco-Elastic Solid

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Applied Mathematics 2016年第16期7卷 1903-1918页

作者： Franz Konstantin Fuss Centre for Design Innovation Swinburne University of Technology Melbourne Australia

This paper investigates the equilibrium of fractional derivative and 2nd derivative, which occurs if the original function is damped (damping of a power-law viscoelastic solid with viscosities η of 0 ≤ η ≤ 1), where the fractional derivative corresponds to a force applied to the solid (e.g. an impact force), and the second derivative corresponds to acceleration of the solid’s centre of mass, and therefore to the inertial force. Consequently, the equilibrium satisfies the principle of the force equilibrium. Further-more, the paper provides a new definition of under- and overdamping that is not exclusively disjunctive, i.e. not either under- or over-damped as in a linear Voigt model, but rather exhibits damping phases co-existing consecutively as time progresses, separated not by critical damping, but rather by a transition phase. The three damping phases of a power-law viscoelastic solid—underdamping, transition and overdamping—are characterized by: underdamping—centre of mass oscillation about zero line;transition—centre of mass reciprocation without crossing the zero line;overdamping—power decay. The innovation of this new definition is critical for designing non-linear visco-elastic power-law dampers and fine-tuning the ratio of under- and overdamping, considering that three phases—underdamping, transition, and overdamping—co-exist consecutively if 0 < η < 0.401;two phases—transition and overdamping—co-exist consecutively if 0.401 < η < 0.578;and one phase— overdamping—exists exclusively if 0.578 < η < 1.

关键词： Fractional Derivative Non-Linear Visco-Elasticity power law Mittag-Leffler Function Underdamping Overdamping Innovative Design of Material Damping

power laws and Skew Distributions

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Communications in Computational Physics 2012年第8期12卷 721-731页

作者： Reinhard Mahnke Jevgenijs Kaupuzs Mãrtins Brics Institute of Physics Rostock UniversityD-18051 RostockGermany Institute of Mathematics and Computer Science University of LatviaLV-1459 RigaLatvia

power-law distributions and other skew distributions,observed in various models and real systems,are considered.A model,describing evolving systems with increasing number of elements,is considered to study the distribution over element *** power-law distributions are *** non-stationary skew distributions are obtained and analyzed,based on exact solutions and numerical simulations.

关键词： power law critical exponent evolving system skew distribution