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Content delivery network and its regulation

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The Journal of China Universities of Posts and Telecommunications 2006年第4期13卷 98-101页

作者： PENG Jiu-sheng liang Xiong-jian School of Economics and Management Beijing University of Posts and Telecommunications Beijing 100876 China

First, this article provides an introduction to the content delivery network （CDN）, which has wide prospects but is still in its early stages in China. Second, this article depicts the present situation and the developing characteristics of CDN in China. Elaborating on the above-mentioned two points, this article identifies the numerous problems that are encountered during the development of CDN, such as indistinct service positioning and the hidden troubles of information security. Finally, this article presents several countermeasures for handling the problems, such as opening the market widely, making a rational service positioning, strengthening the regulation on information security, and punishing illegal operations and unfair competition.

关键词： CDN Intemet information security

Formation mechanism of the protective layer in a blast furnace hearth

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International Journal of Minerals,Metallurgy and Materials 2015年第10期22卷 1017-1024页

作者： Ke-xin Jiao jian-liang Zhang Zheng-jian Liu Meng Xu feng Liu School of Metallurgical and Ecological Engineering University of Science and Technology Beijing State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Shougang Research Institute of Technology

A variety of techniques, such as chemical analysis, scanning electron microscopy-energy dispersive spectroscopy, and X-ray diffraction, were applied to characterize the adhesion protective layer formed below the blast furnace taphole level when a certain amount of titanium-bearing burden was used. Samples of the protective layer were extracted to identify the chemical composition, phase assemblage, andistribution. Furthermore, the formation mechanism of the protective layer was determined after clarifying the source of each componenFinally, a technical strategy was proposed for achieving a stable protective layer in the hearth. The results show that the protective layemainly exists in a bilayer form in the sidewall, namely, a titanium-bearing layer and a graphite layer. Both the layers contain the slag phaswhose major crystalline phase is magnesium melilite（Ca2Mg Si2O7） and the main source of the slag phase is coke ash. It is clearly determinethat solid particles such as graphite, Ti（C,N） and Mg Al2O4play an important role in the formation of the protective layer, and the key factofor promoting the formation of a stable protective layer is reasonable control of the evolution behavior of coke.

关键词： blast furnaces hearths protective layers electroch

Fractal-Form of Fe Aggregate Cluster

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Chinese Physics Letters 1994年第1期11卷 35-38页

作者： liang Yiping DENG Zhaojing LI jian Department of Physics Southwest Teacher UniversityChongqing 630715

The form of the bigger clusters composed of aggregate ultrafine Fe particles possesses obvious fractal character and *** the increase of aggregate density,the extended,compensated and collapsed states emerge successively,and the fractal features are *** ideal fractal dimension D0 of magnetic aggregate clusters is suggested between 2 and 4.

关键词： fractal aggregate successively

On Total Colorings of Some Special 1-planar Graphs

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Acta Mathematicae Applicatae Sinica 2017年第3期33卷 607-618页

作者： Lin SUN jian-liang WU Hua CAI Department of Mathematics Changji University School of Mathematics Shandong University

A graph is 1-planar if it can be drawn on the plane so that each edge is crossed by at most one other edge. In this paper, we verify the total coloring conjecture for every 1-planar graph G if either △（G） ≥9 and g（G）≥ 4, or △（G） ≥ 7 and g（G）≥5, where △（G） is the maximum degree of G and g（G） is the girth of G.

关键词： 1-planar graph total coloring discharging method girth r-minimal graph

Forecasting Fractures in Coal Seams by Using Azimuthal Anisotropy from P-Wave Seismic Data

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Journal of China University of Mining and Technology 2007年第1期17卷 11-14页

作者： DONG Shou-hua YUE jian-hua ZHANG fen-xuan School of Resource and Earth Science China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Geophystcal Prospectmg Team Coal Geological Bureau of Shaanxi Province Xi＇an Shaanxi 710005 China

If the thickness of coal seams and the lithology of both roofs and floors of coal seams have not changed at all or only a little, then it is thought that the elastic anisotropy of coal seams depends mainly on fractures and obeys the horizontally symmetric model of an azimuth anisotropy. For a fixed offset, the amplitude A of the reflection P-wave and the cosine of 2φ has an approximately linear relation, (φ is the source-detector azimuth with respect to the fracture strike. Based on this relationship, many things can be done, such as the extraction of macro bins, the correction of residual normal moveout, the formation of azimuth gather, the transformation and normalization of azimuth gathers and the extraction of reflection wave amplitudes of coal seams. The least squares method was used to inverse theoretically the direction and density of fractures of coal seams. The result is in good agreement with the regional geological structure, indicating that the azimuth anisotropic analysis of the P-wave is feasible in evaluating the density and direction of fractures in coal seams.

关键词： coal fracture azimuth anisotropic analysis P-wave

In Situ Imaging of Layer-by-Layer Sublimation of Suspended Graphene

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Nano Research 2010年第1期3卷 43-50页

作者： jian Yu Huang liang Qi Ju Li Center for Integrated Nanotechnologies(CINT) Sandia National LaboratoriesAlbuquerqueNew Mexico 87185USA Department of Materials Science and Engineering University of PennsylvaniaPhiladelphiaPennsylvania 19104USA

An individual suspended graphene sheet was connected to a scanning tunneling microscopy probe inside a transmission electron microscope,and Joule heated to high *** high temperatures and under electron beam irradiation,the few-layer graphene sheets were removed layer-by-layer in the viewing area until a monolayer graphene was *** layer-by-layer peeling was initiated at vacancies in individual graphene *** vacancies expanded to form nanometer-sized holes,which then grew along the perimeter and propagated to both the top and bottom layers of a bilayer graphene joined by a bilayer *** layer-by-layer peeling was induced by atom sublimation caused by Joule heating and facilitated by atom displacement caused by high-energy electron irradiation,and may be harnessed to control the layer thickness of graphene for device applications.

关键词： Graphene sublimation in situ electron microscopy vacancy hole bilayer edge

Theoretical Explanation and Improvement to the Flare Model of Lithography Based on the Kirk Test

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Chinese Physics Letters 2011年第6期28卷 337-340页

作者： CHEN De-liang CAO Yi-Ping HUANG Zhen-fen Department of Opto-Electronics Sichuan UniversityChengdu 610065

The Kirk test has good precision for measuring stray light in optical lithography and is the usual method of measuring stray ***,Kirk did not provide a theoretical explanation to his simulation *** attempt to give Kirk's model a kind of theoretical explanation and a little improvement based on the model of point spread function of scattering and the theory of statistical *** is indicated by simulation that the improved model fits Kirk's measurement data better.

关键词： explanation optics lithography

Formation mechanisms and sequence response of authigenic grain-coating chlorite: evidence from the Upper Triassic Xujiahe Formation in the southern Sichuan Basin, China

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Petroleum Science 2016年第4期13卷 657-668页

作者： Yu Yu liang-Biao Lin jian Gao State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology Institute of Sedimentary Geology Chengdu University of Technology

Authigenic grain-coating chlorite is widely distributed in the clastic rocks of many sedimentary basins around the world. These iron minerals were mainly derived from flocculent precipitates formed when rivers flow into the ocean, especially in deltaic environments with high hydrodynamic conditions. At the same time, sandstone sequences with grain-coating chlorites also tend to have relatively high glauconite and pyrite content. EPMA composition analysis shows that glauconites with ‘‘high Al and low Fe’’ content indicate slightly to semi-saline marine environments with weak alkaline and weakly reducing conditions. By analyzing the chlorite-containing sandstone bodies of the southern Sichuan Xujiahe Formation, this study found that chlorite was mainly distributed in sedimentary microfacies, including underwater distributary channels, distributary channels, shallow lake sandstone dams, and mouth bars. Chlorite had a tendency to form in the upper parts of sandstone bodies with signs of increased base level, representing the influence of marine（lacustrine）transgression. This is believed to be influenced by megamonsoons in the Middle and Upper Yangtze Region during the Late Triassic Epoch. During periods of abundant precipitation, river discharges increased and more Fe particulates flowed into the ocean（lake）. In the meantime,increases or decreases in lake level were only affected byprecipitation for short periods of time. The sedimentary environment shifted from weakly oxidizing to weak alkaline, weakly reducing conditions as sea level increased, and Fe-rich minerals as authigenic chlorite and glauconite began to form and deposit.

关键词： Sichuan Basin Xujiahe Formation Graincoating chlorite Glauconite Pyrite

A Totally(Δ+1)-colorable 1-planar Graph with Girth at Least Five

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Acta Mathematica Sinica,English Series 2016年第11期32卷 1337-1349页

作者： Lin SUN jian liang WU Hua CAI School of Mathematics Shandong University Ji'nan 250100 P. R. China Department of Mathematics Changji University Changji 831100 P. R. China

A graph is 1-planar if it can be drawn on the plane so that each edge is crossed by at most one other edge. In this paper, we prove that every 1-planar graph G with maximum degree △（G）〉 12 and girth at least five... 详细信息

关键词： 1-planar graph total coloring discharging method girth