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An SGS Model and Its Application

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Communications in Nonlinear Science and Numerical Simulation 1999年第2期4卷 87-90页

作者： Zhengtong XIE Jiachun LI (Institute of Mechanics, chinese academy of sciences, {3. 100080,{4.) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Based on the turbulent energy and structure function model, a subgridstress model named transitional structure function (TSF) is proposed, which exhibitsmore satisfactory performance than the previous one when applied in turbulent flow withinand above forest *** time and horizontal averaged statistics such as mean verticalprofiles of wind velocity, Reynolds stress, turbulent kinetic energy etc., and instantaneousfields as well are in general agreement with earlier observations, at least in a qualitativesense.

关键词： Large-Eddy simulation SGS model turbulent flow canopy

Constraints on smoothness parameter and dark energy using observational H(z) data

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Research in Astronomy and Astrophysics 2011年第2期11卷 125-136页

作者： Hao-Ran Yu1,Tian Lan1,Hao-Yi Wan2,Tong-Jie Zhang1,3.and Bao-Quan Wang4.1 Department of Astronomy,beijing Normal University,beijing 100875,china 2 Business Office,beijing Planetarium,beijing 10004.,china 3.Center for high energy physics,Peking University,beijing 100871,china 4.Department of physics,Dezhou University,Dezhou 253.23.china Department of Astronomy Beijing Normal University Beijing 100875 China Business Office Beijing Planetarium Beijing 100044 China Center for high energy physics Peking University Beijing 100871 China Department of physics Dezhou University Dezhou 253023 China

With large-scale homogeneity,the universe is locally inhomogeneous,clustering into stars,galaxies and larger *** property is described by the smoothness parameter α which is defined as the proportion of matter in the form of intergalactic *** we consider the inhomogeneities over a small scale,there should be modifications of the cosmological distances compared to a homogenous *** and Roeder developed a second-order ordinary differential equation（D-R equation） that describes the angular diameter distance-redshift relation for inhomogeneous cosmological ***,we may obtain the D-R equation for observational H（z） data（OHD）.The density-parameter ΩM,the state of dark energy ω,and the smoothness-parameter α are constrained by a set of OHD in a spatially flat XCDM universe as well as a spatially flat XCDM *** using a χ2 minimization method,we get α = 0.81＋0.19-0.20 and ΩM = 0.3.＋0.12-0.06 at the 1σ confidence *** we assume a Gaussian prior of ΩM = 0.26 ± 0.1,we get α = 0.93.0.07-0.19 and ΩM = 0.3.＋*** the XCDM model,α is constrained to α≥ 0.80 but ω is weakly constrained around-1,where ω describes the equation of state of the dark energy（pX = ωρX）.We conclude that OHD constrains the smoothness parameter more effectively than the data of SNe Ia and compact radio sources.

关键词： cosmology -- dark energy -- cosmological parameters

Capability description and discovery of Internetware entity

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Science china(Information sciences) 2010年第4期53卷 685-703页

作者： WANG PuWei1*, JIN Zhi2,3. & LIU HongYan4.1Key Laboratory of Data Engineering and Knowledge Engineering of the Ministry of Education, Renmin University of china, beijing 100872, china 2Key Laboratory of {3. Confidence Software Technologies of the Ministry of Education, Peking University, beijing 100871, china 3.6} of Mathematics and System sciences, chinese academy of sciences, beijing 100190, china 4.epartment of Management Science and Engineering, Tsinghua University, beijing 100084. china 1. Key Laboratory of Data Engineering and Knowledge Engineering of the Ministry of Education Renmin University of China Beijing 100872 China2. Key Laboratory of High Confidence Software Technologies of the Ministry of Education Peking University Beijing 100871 China3. Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100190 China4. Department of Management Science and Engineering Tsinghua University Beijing 100084 China

Internetware can be formed through aggregation of Internetware entities bottom-up to satisfy the user's requirements. In the process, capability description of Internetware entity plays an important role. This paper proposes a capability description of Internetware entity based on environment ontology. The environment ontology includes environment entities and possible interactions with the environment entities in a particular domain. Tree-like hierarchical state machines are also included in the ontology to describe domain life-cycle of the environment entities. On the basis of the ideas, the capability of Internetware entity is embodied by interacting with environment entities and the changes of the environment entities during the interactions. Finally, this paper describes the matchmaking between capability descriptions of Internetware entities to support the discovery of Internetware entity. An example of online education course is given to illustrate the ideas.

关键词： Internetware capability description domain environment ontology tree-like hierarchical state machine

Exploration of combined adjustment laws about IGV,stator and rotational speed in off-design conditions in an axial compressor

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中国科学：技术科学英文版 2010年第4期53卷 969-975页

作者： HU YanMing1,2 & NIE ChaoQun1 1 Key Laboratory of Advanced energy and Power Technology,Institute of Engineeting Thermophysics,chinese {3. of Science,{4. 100190,china 2 Graduate School of chinese {3. of sciences,{4. 100190,china 1. Key Laboratory of Advanced energy and Power Technology Institute of Engineeting Thermophysics Chinese Academy of Science Beijing 100190 China2. Graduate School of Chinese Academy of Sciences Beijing 100190 China

Experimental investigations are performed in a three-stage low-speed axial compressor with variable inlet guide vanes(IGV) and adjustable *** characteristics of the compressor,especially the efficiency and stall margin,are analyzed in design and off-design operation conditions by adjusting stagger angles of IGV and stators as well as changing the rotational *** experimental results show that the off-design performance of the multistage axial compressor is improved by restaggering of IGV and stators related to rotational *** the background of engineering applications,digital signal processing(DSP) technique is used to realize online adjustment of stagger angles according to the corresponding relations between incidence angles of rotor and rotational speed.

关键词： axial compressor IGV surge DSP techniques off-design

An efficient quantum secret sharing protocol with orthogonal product states

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Science china(physics,Mechanics & Astronomy) 2007年第3期50卷 331-338页

作者： YANG YuGuang1,2, WEN QiaoYan3.& ZHU FuChen4.1 School of Computer, beijing University of Technology, beijing 100022, china 2 State Key Laboratory of Information Security, Graduate University of {3. academy of sciences, beijing 100022, china 3.School of Science, beijing University of Posts and Telecommunications, beijing 100876, china 4.National Key Laboratory for Modern Communications, Chengdu 61004., china 1. School of Computer Beijing University of Technology Beijing 100022 China 2. State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100022 China 3. School of Science Beijing University of Posts and Telecommunications Beijing 100876 China 4. National Key Laboratory for Modern Communications Chengdu 610041 China

An efficient quantum secret sharing protocol with orthogonal product states in the 3.3.Hilbert space is presented. The particles in the orthogonal product states form two particle sequences. One sequence is sent to Bob and the other is sent to Charlie after rearranging the particle orders. With the help of Alice, Bob and Charlie make the corresponding local measurement to obtain the information of the or- thogonal product states prepared. This protocol has many distinct features such as great capacity and high efficiency.

关键词： quantum secret sharing orthogonal product state orthogonal measurement

Experimental demonstration of a new concept of drag reduction and thermal protection for hypersonic vehicles

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Acta Mechanica Sinica 2009年第3期25卷 417-419页

作者： Zonglin Jiang Yunfeng Liu Guilai Han Wei Zhao Key Laboratory of high Temperature Gas Dynamics, Institute of Mechanics, chinese academy of {3., 100190 {4., china Key Laboratory of high Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences 100190 Beijing China

A new idea of drag reduction and thermal protection for hypersonic vehicles is proposed based on the combination of a physical spike and lateral jets for shockreconstruction. The spike recasts the bow shock in front of a blunt body into a conical shock, and the lateral jets work to protect the spike tip from overheating and to push the conical shock away from the blunt body when a pitching angle exists during flight. Experiments are conducted in a hypersonic wind tunnel at a nominal Mach number of 6. It is demonstrated that the shock/shock interaction on the blunt body is avoided due to injection and the peak pressure at the reattachment point is reduced by 70% under a 4. attack angle.

关键词： Hypersonic vehicle Shock-reconstruction. Drag reduction Thermal protection Spike and lateral jets

Calculation of triaxial superdeformation in ^(174.Hf

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Science china(physics,Mechanics & Astronomy) 2007年第5期50卷 553-557页

作者： YU ShaoYing1,2,4. LI XiaoWei2, SHEN CaiWan1,5 & CHEN YongShou3.4.1 School of Science, Huzhou Teachers College, Huzhou 3.3.00, china 2 College of Mathematics, {4. and Information Engineering, Zhejiang Normal University, Jinhua 3.1000, china 3.0} Institute of Atomic energy, beijing 1024.3. china 4.Institute of Theoretical {4., chinese {14. of sciences, beijing 100080, china 5 Center of Theoretical Nuclear {4., National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 73.000, china 1. School of Science Huzhou Teachers College Huzhou 313000 China 2. College of Mathematics Physics and Information Engineering Zhejiang Normal University Jinhua 321000 China 4. Institute of Theoretical physics Chinese Academy of Sciences Beijing 100080 China 5. Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China 3. china Institute of Atomic energy Beijing 102413 China

A two-dimensional Total Routhian Surface (TRS) calculation with the fixed hexa- decapole deformation ε4.= 0.03.was carried out for several configurations of 174.f. Results indicate that the shell corrections have an important contribution to the formation of triaxial superdeformation in 174.f and some possible configuration assignments are made to the 4.TSD bands experimentally found in 174.f.

关键词： Total Routhian Surface (TRS), triaxial superdeformation, configuration

^(13.)Cs Redistribution in Thin Stony Soil of a Carbonate Rock Slope in Southwest china

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Pedosphere 2011年第1期21卷 37-45页

作者： LI Hao ZHANG Xin-Bao WANG Kc-Lin WEN An-Bang Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 (China) Graduate University Chinese Academy of Sciences Beijing 100049 (China) State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 (China) Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 (China)

The fallout radionuclide cesium-13.(13. Cs) has been widely employed as a tracer for assessment of soil loss from thick uniform soils;however,few studies have been conducted on thin stony soils on slopes underlain by carbonate rocks which are widely distributed in karst *** derived from 13. Cs measurement of soil samples collected along a carbonate rock slope with thin stony soil where neither soil erosion nor deposition occurred was used to investigate the characteristics of 13. Cs redistribution in a karst area of Southwest *** results indicated that the 13. Cs inventories of the surface soil on the slope studied were much lower than that of the local 13. Cs reference inventory and the 13. Cs activities were much higher than those on slopes with thick uniform *** spatial distribution of 13. Cs inventories was characterized by considerable *** high 13. Cs depletion in the stony soil of the slope studied was mainly because a considerable proportion of the fallout input of 13. Cs could be lost with runoff and the dissolution of carbonate particles in the soil promoted the loss of 13. *** demonstrated that the rates of soil loss could not be estimated from the degree of depletion of the 13. Cs inventory relative to the local reference inventory for the thin stony soil of the rocky slope underlain by carbonate rocks in the study area in the way that has been widely used in areas with thick uniform soils.

关键词： carbonate dissolution, ^13.Cs fallout, ^13.Cs inventory karst area runoff

Enthalpy and entropy interaction parameters of sodium chloride with some monosaccharides in water

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Science china Chemistry 2004年第1期47卷 59-66页

作者： ZHUO Kelei, WANG Jianji, BAI Guangyue, YAN Haike & WANG HangingSchool of Chemistry and Environmental Science, Henan Normal University, Xinxiang 4.3.02, china Institute of Chemistry, chinese academy of {3., beijing 100080, china Lanzhou Institute of Chemical physics, chinese academy of {3., Lanzhou 73.000, china 1. School of Chemistry and Environmental Science Henan Normal University 453002 Xinxiang China 2. Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China 3. Lanzhou Institute of Chemical physics Chinese Academy of Sciences 730000 Lanzhou China

Dilution enthalpies of sodium chloride and some monosaccharides (glucose, galactose, xylose, arabinose, and fructose) in water and mixing enthalpies of aqueous sodium chloride and these monosaccharide solutions were measured by using an improved precision semimicro-titration calorimeter. Transfer enthalpies of sodium chloride from water to aqueous saccharide solutions were evaluated as well as enthalpy interaction parameters of sodium chloride with these monosaccharides in water. Combined with Gibbs energy interaction parameters, entropy interaction parameters were also obtained. The results show that interactions of the saccharides with sodium chloride depend on the stereochemistry of saccharide molecules. These interaction parameters can identify stereochemical structure of saccharide molecules. Keywords sodium chloride - monosaccharide - enthalpy interaction parameter - entropy interaction parameter - calorimetry

关键词： sodium chloride, monosaccharide, enthalpy interaction parameter, entropy interaction parameter, calorimetry.