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Communication network designing:Transmission capacity,cost and scalability

science china(Information sciences) 2012年第11期55卷 2454-2465页

作者： ZHANG GuoQiang1,2,3 & ZHANG GuoQing1 1institute of Computing technology,Chinese Academy of sciences,Beijing 100190,china 2School of Computer science and technology,nanjing Normal university,nanjing 210046,china 3provincial Key Laboratory for Computer Information processing technology,Soochow university,Suzhou 215000,china 1. institute of Computing technology Chinese Academy of Sciences Beijing 100190 China2. School of Computer Science and Technology Nanjing Normal University Nanjing 210046 China3. Provincial Key Laboratory for Computer Information Processing Technology Soochow University Suzhou 215000 China

Despite the growing number of works centering around the traffic dynamics on complex networks,these researches still have some common shortcomings,e.g.,too simple traffic flow model and lack of considerations for the designing cost and scalability *** paper builds on a more realistic traffic flow model,and offers a holistic view on the network designing *** addition to the extensively studied transmission capacity,this paper takes designing cost and scalability as two other designing objectives,and presents a quantitative study of how different designing choices independently and collectively influence these objectives by the introduction of a cartesian coordinate *** is shown that different kinds of network topologies display different shapes of achievable solution spaces and exhibit different abilities to achieve cost-effective and scalable *** particular,we find the philosophy underlying empirical network designing and engineering today fails to meet the cost-effective and scalable designing requirements,and propose a cost-effective and scalable designing scheme for BA-like networks,i.e.,the efficient routing combined with effective betweenness based link bandwidth *** addition,when designing a thoroughly new network from the beginning,we find that Er network is a good candidate to achieve cost-effective and scalable designing in most settings.

关键词： cost-effective communication network designing network transmission efficiency network topology traffic dynamics next generation network scalable network designing

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paddy Soil Stability and Mechanical properties as Affected by Long-Term Application of Chemical Fertilizer and Animal Manure in Subtropical china

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pedosphere 2007年第5期17卷 568-579页

作者： LI Jiang-Tao ZHANG Bin School of Geographic and Oceanographic sciences Nanjing University Nanjing 210093 （China） institute of Soil science Chinese Academy of Sciences Nanjing 210008 （China）

Wet stability, penetration resistance （pr）, and tensile strength （TS） of paddy soils under a fertilization experiment for 22 years were determined to elucidate the function of soil organic matter in paddy soil stabilization. The treatments included no fertilization （CK）, normal chemical fertilization （NpK）, double the NpK application rates （2NpK）, and NpK mixed with organic manure （NpK＋OM）. Compared with CK, Fertilization increased soil organic carbon （SOC） and soil porosity. The results of soil aggregate fragmentation degree （SAFD） showed that fast wetting by water was the key fragmentation mechanism. Among the treatments, the NpK＋OM treatment had the largest size of water-stable aggregates and greatest normal mean weight diameter （NMWD）（p ≤ 0.05）, but the lowest pr and TS in both cultivated horizon （Ap） and plow pan. The CK and 2NpK treatments were measured with pr 〉 2.0 Mpa and friability index 〈 0.20, respectively, in the Ap horizon, suggesting that the soils was mechanically unfavourable to root growth and tillage. In the plow pan, the fertilization treatments had greater TS and pr than in CK. TS and pr of the tested soil aggregates were negatively correlated to SOC content and soil porosity. This study suggested that chemical fertilization could cause deterioration of mechanical properties while application of organic manure could improve soil stability and mechanical properties.

关键词： soil aggregate stability chemical fertilization organic matter penetration resistance tensile strength

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The　photon　theory　hypothesis　about　photon　tunneling　microscope＇s　subwavelength　resolution

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光电子·激光 1996年第4期7卷 236-239+259页

作者： Yanbin Zhu Junfu Ma(Laser Li fe science institute, South china Normal university, Guangzhou 510631,p.r.china) 华南师范大学激光生命科学所广东广州

Ｔｈｅｐｈｏｔｏｎｔｈｅｏｒｙｈｙｐｏｔｈｅｓｉｓａｂｏｕｔｐｈｏｔｏｎｔｕｎｎｅｌｉｎｇｍｉｃｒｏｓｃｏｐｅ＇ｓｓｕｂｗａｖｅｌｅｎｇｔｈｒｅｓｏｌｕｔｉｏｎ￥ＹａｎｂｉｎＺｈｕ；ＪｕｎｆｕＭａ（ＬａｓｅｒＬｉｆｅ... 详细信息

Ｔｈｅｐｈｏｔｏｎｔｈｅｏｒｙｈｙｐｏｔｈｅｓｉｓａｂｏｕｔｐｈｏｔｏｎｔｕｎｎｅｌｉｎｇｍｉｃｒｏｓｃｏｐｅ＇ｓｓｕｂｗａｖｅｌｅｎｇｔｈｒｅｓｏｌｕｔｉｏｎ￥ＹａｎｂｉｎＺｈｕ；ＪｕｎｆｕＭａ（ＬａｓｅｒＬｉｆｅＳｃｉｅｎｃｅＩｎｓｔｉｔｕｔｅ，...

关键词： tunneling hypothesis microscope about resolution subwavelength theory The photon

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properties of nonadiabatic quantum fluctuations of the strongly coupled electron-phonon systems

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science china(physics,Mechanics & Astronomy) 2008年第3期51卷 258-268页

作者： pANG XiaoFeng institute of Life science and technology,university of Electronic science and technology of china,Chengdu 610054,china International Centre for Materials physics,Chinese Academy of sciences,Shenyang 110015,china institute of Life science technology University of Electronic Science technology of china Chengdu 610054 China International Centre for Materials physics Chinese Academy of Sciences Shenyang 110015 China

A new variational-ansatz of states of electrons and phonons was proposed on the basis of the Holstein model in strongly coupled electron-phonon systems for studying the influence of nonadiabatic phonon fluctuation,arising from the motion and density fluctuation of electrons,on the properties of ground state,uncertainty relation,stability of polarons,charge density wave (CDW) and phonon staggered ordering. The new ansatz represents the correlation among the displacement and squeezing states of phonons and polaron’s state of electrons as well as the squeezing-antisqueezing effect. The correlation and squeezing-antisqueezing ef-fect result in the decrease of ground state energy,enhancement of stability of the systems,increase of binding energy of the polarons,weakening of the growing speed of polaron narrowing of the electron band,increase of the charge density wave order and suppression of the increased tendency of anomalous quantum fluctuation of the phonons in such a case,when compared with the uncorrelated case in the systems. The results obtained show that the ground state determined by the new state ansatz is most stable,thus the new ansatz describing the properties of the coupled electron phonon systems is very relevant and available,especially in strongly coupled and largely squeezed cases.

关键词： squeezing-antisqueezing effect state-ansatz polaron coupled electron-phonon systems quantum fluctuation

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p2p traffic optimization

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science china(Information sciences) 2012年第7期55卷 1475-1492页

作者： ZHANG GuoQiang 1,2 ,TANG MingDong 3 ,CHENG SuQi 2,4 ,ZHANG GuoQing 2 ,SONG HaiBin 5 ,CAO JiGuang 6 & YANG Jing 7 1 School of Computer science and technology,nanjing Normal university,nanjing 210046,china 2.institute of Computing technology,Chinese Academy of sciences,Beijing 100190,china 3 School of Computer science and Engineering,Hunan university of science and technology,Xiangtan 411201,china 4 Graduate university of Chinese Academy of sciences,Beijing 100190,china 5 nanjing r&D Center,Huawei Technologies,nanjing 210012,china 6 china Academy of Telecommunication research of MIIT,Beijing 100191,china 7 china Mobile research institute,Beijing 100053,china 1. School of Computer science and technology Nanjing Normal University Nanjing 210046 China2. Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China3. School of Computer Science and Engineering Hunan University of Science and Technology Xiangtan 411201 China4. Graduate University of Chinese Academy of Sciences Beijing 100190 China5. Nanjing R&D Center Huawei Technologies Nanjing 210012 China6. China Academy of Telecommunication Research of MIIT Beijing 100191 China7. China Mobile Research Institute Beijing 100053 China

peer-to-peer (p2p) based content distribution systems have emerged as the main form for content distribution on the Internet,which can greatly reduce the distribution cost of content providers and improve the overall system ***,the mismatch between the overlay and underlay networks causes large volume of redundant traffic,which intensifies the tension between p2p content providers and ***,how to efficiently use network resources to reduce the traffic burden on the ISps is crucial for the sustainable development of p2p *** paper surveys the state-of-art p2p traffic optimization technologies from three perspectives:p2p cache,locality-awareness and data *** details,comparison between these technologies and their applicabilities are presented,followed by a discussion of the issues that remain to be addressed and the direction of future content distribution research.

关键词： p2p traffic localization p2p traffic optimization p2p cache locality-awareness network coding content-centric network

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Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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science china Earth sciences 2008年第5期51卷 654-664页

作者： HU Guang1,2, JIN ZhangDong1 & ZHANG Fei3 1 State Key Laboratory of Loess and Quaternary Geology, institute of Earth Environment, Chinese Academy of sciences, Xi’an 710075, china 2 Graduate university of the Chinese Academy of sciences, Beijing 100049, china 3 College of resources and Environmental science, nanjing Agricultural university, nanjing 210095, china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China Graduate university of the Chinese Academy of sciences Beijing 100049 China College of resources and Env

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15–55 m) of the Hequing Basin in Yunnan province, southwest china. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo reflected the changes in its ambient water composition and ecology; (2) the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3) the molar Sr/Ca ratios were mainly controlled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in future in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

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Large-eddy simulation of formation of three-dimensional aeolian sand ripples in a turbulent field

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science china(physics,Mechanics & Astronomy) 2008年第8期51卷 945-960页

作者： WU ChuiJie1,WANG Ming2 & WANG Liang3 1 State Key Laboratory of Structural Analysis for Industrial Equipment,Dalian university of technology,Dalian 116024,china 2 Yellow river institute of Hydraulic research,Zhengzhou 450003,china 3 research Center for Fluid Dynamics,science School,pla university of science and technology,nanjing 211101,china State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China Yellow river institute of Hydraulic research Zhengzhou 450003 China research Center for Fluid Dynamics Science School PLA University of Science and Technology Nanjing 211101 China

With the method of large-eddy simulation,the equation of spherule motion and the method of immersed boundary condition,numerical simulations of three-dimen-sional turbulent aeolian motion and the formation of sand ripples under three-di-mensional turbulent wind and the mutual actions of saltation and creeping motion were carried out. The resulting sand ripples have the form that is flat on the upwind side and steep on the leeward,which is identical to the sand ripples in nature. We also realized the self-restoration process of three-dimensional sand ripples,which shows the correctness of the method of numerical simulation and the models of saltation and creeping. Finally,We analyzed the influence of sand ripples on the three-dimensional turbulent wind field,and found that due to the appearance and development of sand ripples,in the normal direction of ground there exists stronger energy exchange,and moreover,there is close correspondence between the forms of sand ripples and the vorticity close to the ground surface.

关键词： large-eddy simulation equation of spherule motion sand ripples saltation creep

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A Least Included Angles Method with Mean Cumulative Dominance in AHp

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Systems science and Systems Engineering 2000年第1期10卷 1-7页

作者： XU Ze\|shui institute of Communications Engineering pla university of science & technology, nanjing 210016, china

Dominance is an underlying concept in decision making that is used to develop a method to obtain the derived weight. The eigenvector method (EM) [3] is favored because it captures dominance at the level of tolerated inconsistency, the least included angles method (LAM) [1] minimizes error without an explict attempt to capture dominance, but with simplicity and practicality. This paper puts forward a new priority method——the least included angles method with mean cumulative dominance (DLAM) combining the good characteristics of EM and LAM. Compared with the EM, the LAM, the GMDM and the AMDM, the DLAM is a simpler, practical and more rational method in calculating the weight vectors of judgement matrices. The results of the numerical example also show that the DLAM and the EM always derive the same rankings, the other methods such as the LAM, the logarithmic least squares method (LLSM), the GMDM and the AMDM are possible to obtain the rankings, which are different from those derived by the DLAM and the EM.

关键词： AHp DLAM dominance, cumulative dominance matrix

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Spatial and Temporal Variability of N, p and K Balances for Agroecosystems in china

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pedosphere 2005年第3期15卷 347-355页

作者： SHENrun-ping SUNBo ZHAOQi-Guo instituteofSoilscience ChineseAcademyofSciencesNanjing210008（China）／／DepartmentofSpatialInformationScienceNanjingUniversityofInformationScienceandTechnologyNanjing210044（China） instituteofSoilscience ChineseAcademyofSciencesNanjing210008（China）

Nitrogen, phosphorus, and potassium balances for agroecosystems in china from 1993 to 2001 were calculated at national and provincial levels using statistical data and related parameters, and their spatial and temporal variabilities were analyzed with GIS to estimate the potential impacts of nutrient N, p and K surpluses or deficits to soil, water and air. At the national scale, the N and p balances from 1993 to 2001 showed a surplus, with the nitrogen surplus remaining relatively stable from 1997—2001. Although during this period the p surplus pattern was similar to N, it had smaller values and kept increasing as the use of phosphate fertilizer increased year by year. However, K was deficient from 1993 to 2001 even though from 1999 to 2001 the K deficit decreased. The spatial analysis revealed higher N surpluses in the more developed southeastern provinces and lowest in the western and northern provinces where there was less chemical fertilizer input. The serious K deficit mainly occurred in Shanghai and Beijing municipalities, Jiangsu, Zhejiang and Hubei provinces, and Xinjiang autonomous regions. For the years 1992, 1996 and 2001, N surpluses and K deficits had significant positive spatial correlations with per capita gross domestic product (GDp), per capita gross industrial output value, and per capita net income of rural households. This showed that the level of economic development played an important role on nutrient balances in the agroecosystems.

关键词： china economic factors NpK balance spatial and temporal variability

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Simulation study of real-time monitor for BEpC-Ⅱ luminosity

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science china(Technological sciences) 2010年第5期53卷 1215-1219页

作者： SHAN Qing1,2,WU Jian2,XUE Zhen2,XU ZiZong2,HU Tao3,WANG YiFang3 & WANG XiaoLian2 1 College of Material science and technology,nanjing university of Aeronautics and Astronautics,nanjing 210016,china 2 Department of Modern physics,university of science and technology of china,Hefei 230026,china 3 institute of High Energy physics,Chinese Academy of sciences,Beijing 100049,china College of Material science and technology Nanjing University of Aeronautics and Astronautics Nanjing China Department of Modern physics University of Science and Technology of China Hefei China institute of High Energy physics Chinese Academy of Sciences Beijing China

A fast and real time luminosity monitor system will be used in the BEpC-Ⅱ(Beijing Electron positron Collider,china).photons generated in radiative Bhabha scattering at the interaction point are transformed into charged particles,and then the luminosity of each bunch pair is measured through collecting the Cherenkov light produced by charged particles in fused *** whole process happening in the detector is *** physics acceptance and detection threshold with the monitor accu-racy of 1% are set based on the simulation spectra of photoelectron yield calibrated by e-beam data.

关键词： luminosity BEpC-Ⅱ Cherenkov detector radiative Bhabha

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