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Local segment-shared protection based on source egress gateway selection for multi-domain optical mesh networks

Science china(Information Sciences) 2011年第2期54卷 227-235页

作者： ZHANG ShengFeng1,3. PENG YunFeng1,2, DU Shu1, YANG XiaoLong1,2 & LONG KePing1,2 1research Center for Optical Internet and Mobile Information Networks, University of Electronic Science and technology of china, Chengdu 61173., china 2institute of Advanced Network technology and New Serives (ANTS), University of Science and technology beijing, beijing 100083. china 3.0} Center for Optical Internet Networks, Chongqing University of Posts and Telecommunications, Chongqing 400065, china 1. research Center for Optical Internet and Mobile Information Networks University of Electronic Science and Technology of China Chengdu 611731 China3. Research Center for Optical Internet Networks Chongqing University of Posts and Telecommunications Chongqing 400065 China2. Institute of Advanced Network Technology and New Serives (ANTS) University of Science and Technology Beijing Beijing 100083 China

Survivability for multi-domain optical networks is becoming a key parameter due to expanding network. In order to provide the shared-path-protected lightpath in multi-domain optical mesh networks, we propose a protection solution, called GSLSSP. A new source egress gateway selecting mechanism is adopted in this solution. For each connection request, this mechanism can enable the source node to select a better egress gateway node to the destination domain and compute one inter-domain working path near the optimal path with the cooperating of this gateway node, under scalability and domain privacy constraint of multi-domain networks. And then one intra-domain link-disjoint local segment-backup path for each working-segment path is computed out in each single-domain passed by the working path. Simulation evaluation shows that the proposed scheme can provide 100% protection ability for multiple failures. Besides, it is effective in multi-domain path protection with more efficient resource utilization, lower blocking probabilities and less inter-domain cost than other schemes.

关键词： survivability optical mesh networks multi-domains multiple failures segment-shared protection

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Effects of rare earth element lanthanum on the microstructure of copper matrix diamond tool materials

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Rare Metals 2002年第2期21卷 90-94页

作者： JIAChengchang SONGYueqing YUMing WANGTing researchinstituteofPowderMetallurgyUniversityofScienceandtechnology{3. Beijing100083China GeneralresearchinstituteofNon-ferrousMetal Beijing100088China

Effects of rare earth element La on the microstructure of Cumatrix diamond tools were researched under the conditions of variousmaterials components and the process parameters in order to improvematerials properties. SEM, XPS and X-ray were used to investigate thefracture section, microstructure and the element valence inmaterials. The Results shown that the combination of rare earthelement La and transition element Ti is advantageous to the bondingstate Between diamond particles and matrix, so it can improve thematerials properties. Suitable sintering temperature is 790 deg. C.

关键词： rare earth element La interface reaction Copper matrix diamond tool titanium

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The species diversity of fusulinaceans and high-frequency sea-level changes in the Carboniferous-Permian boundary section at Xikou, Zhen'an County,Shaanxi Province, china

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Science china Earth Sciences 2006年第7期49卷 673-683页

作者： ZHANG Haijun1, WANG Xunlian2, DING Lin1, XIA Guoying3.& WANG Lei2 1. institute of Tibetan Plateau research, Chinese Academy of Sciences, beijing 100085, {3. 2. Faculty of Earth Sciences and Mineral Resources, {3. University of Geosciences, beijing 100083. china 3. Tianjin institute of Geology and Mineral Resources, Tianjin 3.0170, {3. 1. institute of Tibetan Plateau research Chinese Academy of Sciences Beijing 100085 China 2. Faculty of Earth Sciences and Mineral Resources China University of Geosciences Beijing 100083 China 3. Tianjin institute of Geology and Mineral Resources Tianjin 300170 China

The study on the interrelation between sea-level changes and biodiversity with its evolu-tion has great significance for understanding the impact of global changes on organic evolution and exploring the inherent laws of life-environment coevolution in geological history. In this paper, the stratigraphic distribution of fusulinacean fauna in the Carboniferous-Permian boundary section at Xikou, Zhen’an County, Shaanxi Province, is analyzed quantitatively, and the relationship between the species diversity of fusulinaceans and relative sea-level changes is discussed. As a whole, the spe-cies numbers of fusulinacean fauna experience a rapid increase and an obvious decline in Xikou, Zhen’an County, from the Late Carboniferous to the Early Permian. There is a significant increase in species diversity around the Carboniferous-Permian boundary, which is one of the biggest bio-events of the fusulinacean fauna, and represents the radiation of Pseudoschwagerininae subfamily in the studied area. Integrated fusulinacean species diversity into sequence stratigraphic framework, de-tailed study suggests that the species diversity of the fusulinaceans is closely related to its relative stratigraphic location, and is essentially controlled by the sea-level changes, especially by the high-frequency sea-level changes. Generally, the species diversity of fusulinaceans is low, and the number of first and last appearance datum is small in the lower unit of high-frequency depositional cycle formed during the quick rise of the sea level; whereas the species diversity of fusulinaceans is high, and the number of first and last appearance datum is large in the upper unit of high-frequency cycle formed during the slow fall of the sea level. Within the third-order depositional sequence, the species diversity of the fusulinaceans at the first flooding surfaces and the maximum flooding surfaces is low, and it increases upward. The fusulinacean species diversity is low within the transgressive syst

关键词： fusulinaceans, species diversity, high-frequency cyclothem, sequence stratigraphy, sea-level changes, Carboniferous-Permian boundary, Zhen'an, Shaanxi.

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Development and Application of High Performance X80 Line Pipe for the 2^(nd) West-East Gas Pipeline

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Journal of Iron and Steel research International 2011年第S1期18卷 39-48页

作者： LI He-lin 1 , HUO Chun-yong 1 , JI Ling-kang 1, 2 , LI Yang 1, 3.(1. CNPC Tubular Goods research institute, Xi’an 710065, china 2. . School of Material Science and Engineering, Xi’an Jiaotong University, Xi’an 710049, china 3. School of Material Science and Engineering, University of Science and technology beijing, beijing 100083. china) CNPC Tubular Goods Res Inst Xian 710065 Peoples R China Xi An Jiao Tong Univ Sch Mat Sci & Engn Xian 710049 Peoples R China Univ Sci & Technol beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

It is the development tendency of gas pipeline to improve strength of line pipe and transmission pressure, which is an important symbol of the progress of gas pipeline technology. The 2nd West-East Gas Pipeline (the 2 nd WEGP) is the largest-scale X80 high pressure gas pipeline project in the world. Through the joint development project by Pipeline Company, research institute, and steel company, a series of achievements of technology have been obtained, which makes it possible to apply pressure of 12 MPa and X80 LSAW and HSAW pipe for the 2 nd WEGP. Specifications of X80 steel and pipe have been issued based on API 5L. High performance X80 steel and pipe have been developed and meets the Specification. General design conception of applying HSAW pipe and LSAW pipe on gas transmission trunk line with large diameter and high pressure has been established. Failure control of the 2 nd WEGP has been carried out to avoid failure and reduce the lost which based on analysis of pipeline failure mode. In this paper, research and development of high performance X80 welded pipe, establishment of technical route of joint application of HSAW and LSAW steel pipe and key technology of failure control are emphatically discussed.

关键词： 2 nd WEGP acicular ferrite failure control arrest toughness strain-based design

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Sulfide-melt inclusions in mantle xenoliths of Hannuoba,china

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Chinese Science Bulletin 1999年第2期44卷 166-170页

作者： XU Jiuhua , CHU Xuelei , ZHOU Yiming , DU YuanfuUniversity of Science and technology beijing, beijing 100083. china {3. University of Geosciences( beijing) , beijing 100083. china The research Center of Mineral Resources Exploration , beijing 100101, {3. institute of Geology, Chinese Academy of Sciences, beijing 100029, {3. University of Science and technology beijing Beijing China china University of Geosciences (beijing) Beijing China The research Center of Mineral Resources Exploration Beijing China institute of Geology Chinese Academy of Sciences Beijing China

Sulfide fluid incluision study on mantle xenoliths of Hannouba has been carried out by EPMA analysis. It is indicated that the Ni/Fe ratios of metal sulfides in sulfide-melt inclusions from Hannuoba seem to be related to host rocks. These data of lherzolite （pentlandite） are obviously higher than those of olivine pyroxenite （mainly pentlandite, partly pyrrhotine）. The LRM analysis shows that sulfur （H2S+SO2） occupies larger proportion in gas composition of CO2 fluid inclusions, generally more than mol 20 %. This may be related to sulfide inclusions which are frequently found.

关键词： mantle xenolith sulfide-melt inclusion EPMA.

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Thermal-mechanical coupled effect on fracture mechanism and plastic characteristics of sandstone

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Science china(Technological Sciences) 2007年第6期50卷 833-843页

作者： ZUO JianPing1,2, XIE HePing2,3. ZHOU HongWei1,2 PENG SuPing1 1 State Key Laboratory of Coal Resources and Safe Mining, china University of Mining and technology, beijing 100083. china 2 {3. of Rock Mechanics and Fractals, china University of Mining and technology, beijing 100083. china 3.Sichuan University, Chengdu 610065, china 1. State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology Beijing 100083 China 2. institute of Rock Mechanics and Fractals China University of Mining and Technology Beijing 100083 China 3. Sichuan University Chengdu 610065 China

Scanning electronic microscopy (SEM) was employed to investigate fractographs of sandstone in mine roof strata under thermal-mechanical coupled effect. Based on the evolution of sandstone surface morphology in the failure process and frac- tography, the fracture mechanism was studied and classified under meso and mi- cro scales, respectively. The differences between fractographs under different tem- peratures were examined in detail. Under high temperature, fatigue fracture and plastic deformation occurred in the fracture surface. Therefore, the temperature was manifested by these phenomena to influence strongly on micro failure mechanism of sandstone. In addition, the failure mechanism would transit from brittle failure mechanism at low temperature to coupled brittle-ductile failure mechanism at high temperature. The variation of sandstone strength under differ- ent temperature can be attributed to the occurrence of plastic deformation, fatigue fracture, and microcracking. The fatigue striations in the fracture surfaces under high temperature may be interpreted as micro fold. And the coupled effect of tem- perature and tensile stress may be another formation mechanism of micro fold in geology.

关键词： sandstone, thermal-mechanical coupled effects, fractograph, plastic deformation, SEM, micro fold

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The State-of-Art and Development Trends of HSLA Steels in china

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Journal of Iron and Steel research International 2011年第S1期18卷 1-13页

作者： WENG Yu-qing 1,YANG Cai-fu 2,SHANG Cheng-jia 3.(1.The Chinese Society for Metals,beijing,PR china 2.Centre Iron and Steel research {3.,beijing,PR china 3.University of Science and technology beijing,beijing,PR china) Chinese Soc Met Beijing Peoples R China Ctr Iron & Steel Res Inst Beijing Peoples R China Univ Sci & Technol beijing Beijing 100083 Peoples R China

During the last decade,the adjustment of product segments always is a very important task of iron industry,and upgrading of steel products has been impelled actively by Chinese iron and steel *** rapidly increasing of iron & steel production,a series of research achievements have been made in the technology area of high strengthtoughness steel,and also have been applied successfully in the actual production,*** technology of fine grain and ultra-fine grain steels,the technology for the control of microalloying ***,It is an important strategic goal of "Twelfth Five-year Plan" for Chinese iron and steel industry that the adjustment of steel product segments and meeting the requirements for upgrading of domestic and oversea equipment manufactory *** HSLA steel with better performance,instead of plain steel,could save steel consumption largely,and also release pressures from resource,energy and *** doubt,it is the only way to realize the sustained development of Chinese iron and steel industry by popularizing the application of HSLA steels vigorously.

关键词： HSLA steel microalloying technology Chinese iron and steel industry

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Rheological Behaviour for Polymer Melts and Concentrated SolutionsPart Ⅱ: Material Function with Nagai Chain Constraints and Determination of Their Parameters from Flow Curves

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Journal of Materials Science & technology 1995年第2期11卷 141-152页

作者： Mingshi SONG Sizhu WU and Xiuyun DU(research institute of Polymeric Materials, beijing University of Chemical {3., beijing, 100029, china) beijing Univ of Chemical technology Beijing China

An integral constitutive equation and a set of material functions for describing the strain history of polymer melts were formulated in terms of the Cauchy-Green and Finger tensors. A simple memory function and the dependence of ηo and τt on M3.4 were derived from the theory of non-linear viscoelasticity with constraints of entanglements for polymer melts and substituted into the Oldroye-Walters-Fredickson constitutive equation. An integral constitutive equation for polymer melts was consequently obtained. Some material functions of the constitutive equation related to certain 'test flow' are examined as follows : (1) simple steady shear flow; (2) steady elongation flow; (3. small-amplitude oscillatory shear flow; (4) stress growth upon the inception of steady shear elongation flow; (5) stress relaxation (modulus and compllance). These theoretical relations for simple steady shear flow were compared with experimental data from our laboratory and references for various polymer melts and concentrated solutions. A good agreement between the theory and experiment was achieved.

关键词： LDPE Material Function with Nagai Chain Constraints and Determination of Their Parameters from Flow Curves Rheological Behaviour for Polymer Melts and Concentrated SolutionsPart Flow GR

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Geological characteristics of large gas provinces and large gas fields in china

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Science china Earth Sciences 2008年第S1期51卷 14-35页

作者： ZOU CaiNeng &TAO ShiZhen research institute of Petroleum Exploration and Development,Petrochina,{3. 100083.china Petrochina Res Inst Petr Explorat & Dev Beijing 100083 Peoples R China

Based on the examination of the global researches on oil and gas provinces and large gas fields and the analysis of the features,attributes and distribution of large gas provinces and gas fields,this paper puts forward three indicators of determining large oil and gas provinces:spatial indicator,reservoir-forming indicator and resource *** classifies the gas accumulated areas and large gas provinces in china and analyzes the controlling factors on the distribution of large gas provinces and large gas fields:the lateral distribution is mainly controlled by high-energy sedimentary facies and constructive diagenetic facies,palaeo-highs and their periclinal zones,deep faults,etc,and the vertical distribution is mainly controlled by unconformities,series of evaporates and deep low-velocity highly-conductive beds,*** also reveals the main geological characteristics of large gas provinces and large gas fields in *** gas fields in four-type basins have their own characteristics and onland large gas fields are dominantly developed in foreland basins and craton basins;there are three types of gas sources,of which,coal is the main source with high gas generating intensity and varying origins;reservoir rocks of the large gas fields(provinces)are of various types and dominated generally by low-middle permeability and porosity pore-type reservoirs;structural traps and litho-stratigraphic traps coexist in Chinese large gas fields and form dense high abundance and large-area low and middle-abundance large gas fields;most of the large gas fields have late hydrocarbon-generation peaks and reservoir formation,and experienced the process of multiple-stage charging and late finalization; large gas provinces(fields)have good sealing and preservation conditions,and evaporates seals are largely developed in large and extra-large gas *** paper intends to shed light on the exploration and development of large gas fields(provinces)through analyzing their geological

关键词： large gas province large gas field indicator of large oil and gas provinces forming condition distribution characteristics geological feature

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SEVERAL　CONSIDERATIONS　ON　HYDROCARBON　GENERATION　MECHANISM　AND　EVOLUTION　OF　CARBONATE　ROCKS

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石油勘探与开发 1996年第5期23卷 75-80页

作者： Cheng Keming Wang Zhaoyun(research institute of Petroleum Exploration and Development, CNPC, beijing, {3. china)

ＳＥＶＥＲＡＬＣＯＮＳＩＤＥＲＡＴＩＯＮＳＯＮＨＹＤＲＯＣＡＲＢＯＮＧＥＮＥＲＡＴＩＯＮＭＥＣＨＡＮＩＳＭＡＮＤＥＶＯＬＵＴＩＯＮＯＦＣＡＲＢＯＮＡＴＥＲＯＣＫＳ￥ＣｈｅｎｇＫｅｍｉｎｇ；ＷａｎｇＺｈａｏｙｕｎ（Ｒｅ... 详细信息

ＳＥＶＥＲＡＬＣＯＮＳＩＤＥＲＡＴＩＯＮＳＯＮＨＹＤＲＯＣＡＲＢＯＮＧＥＮＥＲＡＴＩＯＮＭＥＣＨＡＮＩＳＭＡＮＤＥＶＯＬＵＴＩＯＮＯＦＣＡＲＢＯＮＡＴＥＲＯＣＫＳ￥ＣｈｅｎｇＫｅｍｉｎｇ；ＷａｎｇＺｈａｏｙｕｎ（ＲｅｓｅａｒｃｈＩｎｓｔｉｔｕｔｅｏｆ...

关键词： Marine factes Oil generation of carbonate rocks Mechanism Evaluation Oil-generatingindex Thermal evolution

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