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A Generic Construction of Ciphertext-Policy Attribute- Based Encryption Supporting Attribute Revocation 被引量:7
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作者 WU Qiuxin 《China Communications》 SCIE CSCD 2014年第A01期93-100,共8页
关键词 加密技术 撤销 属性 密文 通用 私有密钥 用户 ABE
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Energy Levels of Strong Coupling Magnetopolaron in Quantum Dot 被引量:16
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作者 ZHouHai-yang GUShi-wei 《Journal of Shanghai University(English Edition)》 CAS 2001年第1期40-43,共4页
By using variational method of Pekar type, we have studied the energy levels of strong coupling magnetopolaron in disk shape quantum dot(QD) and quantum well(QW). Our results show that, with the increasing magnetic f... By using variational method of Pekar type, we have studied the energy levels of strong coupling magnetopolaron in disk shape quantum dot(QD) and quantum well(QW). Our results show that, with the increasing magnetic field and confinement strength, the magnetopolaron binding energy of QD and QW in the ground state and in the excited state is enhanced. The limiting results of bulk type and strict two dimensional type are obtained. 展开更多
关键词 quantum dot strong coupling MAGNETOPOLARON
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Effects of Preform and Pyrolytic Carbon Structure on Thermophysical Properties of 2D Carbon/Carbon Composites 被引量:8
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作者 罗瑞盈 程永宏 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2004年第2期112-118,共7页
Four kinds of carbon/carbon (C/C) composites, including the needled carbon fiber felt/the pyrolytic carbon (two different pyrolytic carbon microstructures), the chopped carbon fiber/the resin + pyrolytic carbon (PyrC)... Four kinds of carbon/carbon (C/C) composites, including the needled carbon fiber felt/the pyrolytic carbon (two different pyrolytic carbon microstructures), the chopped carbon fiber/the resin + pyrolytic carbon (PyrC), and the carbon cloth/PyrC, named as the composites 1#, 4#, 2#, and 3#, are prepared respectively. Effects of the preform and pyrolytic carbon structure on the thermophysical properties of 2D C/C composites are studied. The C/C composites possess low coefficient of thermal expansion (CTE). In a range of some temperatures, the negative expansion emerges in x-y direction for four C/C composites. From 0 to 900℃, the CTE is small and almost linear with the temperatures. The C/C composites have high thermal conductivities (TCs). As a function of temperature, TCs of the C/C composites are varied with the structures of preform and pyrc as well as the direction of heat transfer. In x-y and z direction, TCs differ greatly and that in x-y direction (25.6-174 W/m·K) is several times larger than that in z direction(3.5-50 W/m·K). 展开更多
关键词 carbon/carbon(C/C)composite pyrolytic carbon thermal expansion thermal conductivity
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Teleportation of an Arbitrary Two-Particle State by Two Partial Entangled Three-Particle GHZ States 被引量:5
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作者 DAIHong-Yi CHENPing-Xing LICheng-Zu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5期799-802,共4页
We present a scheme for teleporting an unknown arbitrary two-particle state from a sender to either one of two receivers. The quantum channel is composed of two partial entangled three-particle GHZ states. An unknown ... We present a scheme for teleporting an unknown arbitrary two-particle state from a sender to either one of two receivers. The quantum channel is composed of two partial entangled three-particle GHZ states. An unknown arbitrary two-particle state can be perfectly teleported probabilistically if the sender performs two generalized Bell-state measurements and each receiver introduces an appropriate unitary transformation with the help of the other receiver's Hadamard operations and simple measurements. 展开更多
关键词 概率传输 绝对双粒子态 酉变换 量子力学
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CAVITY FORMATION AND ITS VIBRATION FOR A CLASS OF GENERALIZED INCOMPRESSIBLE HYPER-ELASTIC MATERIALS 被引量:6
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作者 YuanXuegang ZhuZhengyou ChengChangjun 《Acta Mechanica Solida Sinica》 SCIE EI 2004年第4期361-369,共9页
The problem of radial symmetric motion for a solid sphere composed of a class of generalized incompressible neo-Hookean materials, subjected to a suddenly applied surface tensile dead load, is examined.The ana... The problem of radial symmetric motion for a solid sphere composed of a class of generalized incompressible neo-Hookean materials, subjected to a suddenly applied surface tensile dead load, is examined.The analytic solutions for this problem and the motion equation of cavity that describes cavity formation and growth with time are obtained. The e?ect of radial perturbation of the materials on cavity formation and its motion is discussed. The plane of the perturbation parameters of the materials is divided into four regions. The existential conditions and qualitative properties of solutions of the motion equation of the cavity are studied in di?erent parameters’ regions in detail. It is proved that the cavity motion with time is a nonlinear periodic vibration. The vibration center is then determined. 展开更多
关键词 generalized incompressible neo-Hookean materials analytic solution motion equa- tion of cavity nonlinear periodic vibration
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QUALITATIVE ANALYSIS OF SPHERICAL CAVITY NUCLEATION AND GROWTH FOR INCOMPRESSIBLE GENERALIZED VALANIS-LANDEL HYPERELASTIC MATERIALS 被引量:4
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作者 YuanXuegang ZhuZhengyou ChengChangjun 《Acta Mechanica Solida Sinica》 SCIE EI 2004年第2期158-165,共8页
A cavitated bifurcation problem is examined for a sphere composed of a class of generalized Valanis-Landel materials subjected to a uniform radial tensile dead-load. A cavitated bifurcation equation is obtained. An ... A cavitated bifurcation problem is examined for a sphere composed of a class of generalized Valanis-Landel materials subjected to a uniform radial tensile dead-load. A cavitated bifurcation equation is obtained. An explicit formula for the critical value associated with the vari- ation of the imperfection parameters is presented. The distinguishing between the left-bifurcation and right-bifurcation of the nontrivial solution of the cavitated bifurcation equation at the critical point is made. It is proved that there exists a secondary turning bifurcation point on the nontrivial solution branch, which bifurcates locally to the left. It is shown that the dimensionless cavitated bifurcation equation is equivalent to normal forms with single-sided constraint conditions at the critical point by using the singularity theory. The stability and catastrophe of the solutions of the cavitated bifurcation equation are discussed. 展开更多
关键词 incompressible generalized Valanis-Landel material cavitated bifurcation critical dead-load normal form stability and catastrophe
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Science Letters: Discovery of ultrahigh-T spinel-garnet granulite with pure CO2 fluid inclusions from the Altay orogenic belt, NW China 被引量:5
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作者 厉子龙 陈汉林 +1 位作者 SANTOSHM. 杨树锋 《Journal of Zhejiang University Science》 CSCD 2004年第10期1180-1182,共3页
We first report discovery of the spinel-garnet-orthopyroxene granulite with pure CO2 fluid inclusions from the Fuyun region of the late Paleozoic Altay orogenic belt in Central Asia, NW China. The rock is characterize... We first report discovery of the spinel-garnet-orthopyroxene granulite with pure CO2 fluid inclusions from the Fuyun region of the late Paleozoic Altay orogenic belt in Central Asia, NW China. The rock is characterized by an assemblage of garnet, orthopyroxene, spinel, cordierite, biotite, plagioclase and quartz. Symplectites of orthopyroxene and spinel, and orthopyroxene and cordierite indicate decompression under UHT conditions. Mineral chemistry shows that the orthopyroxenes have high XMg and Al2O3 contents (up to 9.23 wt%). Biotites are enriched in TiO2 and XMg and are stable under granulite facies conditions. The garnet and quartz from the rock carry monophase fluid inclusions which show peak melting temperatures of around -56.7℃, indicating a pure CO2 species being presented during the ultrahigh-T metamorphism in the Altay orogenic belt. The inclusions homogenize into a liquid phase at temperatures around 15.3-23.8℃ translating into CO2 densities of the order of 0.86-0.88g/cm^3. Based on preliminary mineral paragenesis, reaction textures and petrogenetic grid considerations, we infer that the rock was subjected to UHT conditions. The CO2-rich fluids were trapped during exhumation along a clockwise P-T path following isothermal decompression under UHT conditions. 展开更多
关键词 UHT CO2 XM h-T TiO2 Al2O3
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PROGRAM-PATTERN MULTIPOLE BOUNDARY ELEMENT METHOD FOR FRICTIONAL CONTACT 被引量:5
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作者 YuChunxiao ShenGuangxian LiuDeyi 《Acta Mechanica Solida Sinica》 SCIE EI 2005年第1期76-82,共7页
A mathematical program is proposed for the highly nonlinear problem involving frictional contact. A program-pattern using the fast multipole boundary element method (FM- BEM) is given for 3-D elastic contact with fric... A mathematical program is proposed for the highly nonlinear problem involving frictional contact. A program-pattern using the fast multipole boundary element method (FM- BEM) is given for 3-D elastic contact with friction to replace the Monte Carlo method. A new optimized generalized minimal residual (GMRES) algorithm is presented. Numerical examples demonstrate the validity of the program-pattern optimization model for node-to-surface contact with friction. The GMRES algorithm greatly improves the computational efciency. 展开更多
关键词 nonlinear programming GMRES algorithm node-to-surface contact FM-BEM
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Crustal thickening in an active margin setting (Philippines): The whys and the hows 被引量:3
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作者 C.B.Dimalanta G.P.Yumul,Jr. 《Episodes》 SCIE 2004年第4期260-264,共5页
A synthesis of crustal thickness estimates was made recently utilizing available field, geochemical, seismicity, shear wave velocity and gravity data in the Philippines. The results show that a significant portion of ... A synthesis of crustal thickness estimates was made recently utilizing available field, geochemical, seismicity, shear wave velocity and gravity data in the Philippines. The results show that a significant portion of the Philippine archipelago is generally characterized by crust with a thickness of around 25 to 30 kilometers. However, two zones, which are made up of a thicker crust (from 30 to 65 km) have also been delineated. The Luzon Central Cordillera region is characterized by thick crust. Another belt of thickened crust is observed in the Bicol-Negros-Panay-Central Mindanao region. This paper examines the interplay of tectonic and magmatic processes and their role in modifying Philippine arc crust. The processes, which could account for the observed crustal thicknesses, are presented. The contributions of magmatic arcs as compared to the contribution of the emplacement and accretion of ophiolite complexes to crustal thickness are also discussed. 展开更多
关键词 地壳增厚 活跃边缘环境 剪力波速度 菲律宾群岛 地质构造
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Numerical Simulation for Roadways in Swelling Rock Under Coupling Function of Water and Ground Pressure 被引量:3
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作者 缪协兴 卢爱红 +1 位作者 茅献彪 张东升 《Journal of China University of Mining and Technology》 2002年第2期120-125,共6页
According to the analogical relation in the governing differential equations of the humidity stress field theory and the temperature stress field theory, the problem of solving the humidity stress field was transforme... According to the analogical relation in the governing differential equations of the humidity stress field theory and the temperature stress field theory, the problem of solving the humidity stress field was transformed into that of solving the temperature stress field by the change of parameters. As a result, the problem of roadways in swelling rock under the coupling function of water and ground pressure can be solved by the analytical module of temperature stress field in software ANSYS. In the numerical simulation mentioned above, three kinds of supporting, i.e. steel support, bolting support and non support, were taken into account, the pressure distribution and deformation state of roadways with a swelling rock floor under the coupling function of water and ground pressure were analyzed and compared with those in the action of only ground pressure. The research results provides a scientific basis for the deformation control of roadways in swelling rock. 展开更多
关键词 膨胀岩 围岩 湿度 数值模拟 压力场
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Binding and Transformation of Extracellular DNA in Soil 被引量:2
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作者 CAIPeng HUANGQiao-Yun +1 位作者 ZHANGXue-Wen CHENHao 《Pedosphere》 SCIE CAS CSCD 2005年第1期16-23,共8页
DNA is the genetic material of various organisms. Extracellular DNA adsorbed or bound on surface-active particles in soils has been shown to persist for long periods against nucleases degradation and still retain the ... DNA is the genetic material of various organisms. Extracellular DNA adsorbed or bound on surface-active particles in soils has been shown to persist for long periods against nucleases degradation and still retain the ability to transform competent cells. This paper reviews some recent advances on the binding and transformation of extracellular DNA in soils,which is fundamental to understanding the nature of the soil, regulating biodiversity, and assessing the risk of releasing genetically engineered microorganisms (GEMs) as well as being helpful for development of the genetic evolutional theory of bacteria. Several influencing factors, such as soil pH, ionic strength, soil surface properties, and characteristics of the DNA polymer, are discussed. To date, the understanding of the type of molecular binding sites and the conformation of adsorbed and bound DNA to soil particles is still in its infancy. 展开更多
关键词 土壤生态学 DNA 脱氧核糖核酸 基因材料 组织吸收
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Petrology, geochemistry and geodynamics of basic granulite from the Altay area, North Xinjiang, China 被引量:3
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作者 厉子龙 陈汉林 +2 位作者 杨树锋 董传万 肖文交 《Journal of Zhejiang University Science》 EI CSCD 2004年第8期979-984,共6页
The basic granulite of the Altay orogenic belt occurs as tectonic lens in the Devonian medium- to lower-grade metamorphic beds through fault contact. The Altay granulite (AG) is an amphibole plagioclase two-pyroxene g... The basic granulite of the Altay orogenic belt occurs as tectonic lens in the Devonian medium- to lower-grade metamorphic beds through fault contact. The Altay granulite (AG) is an amphibole plagioclase two-pyroxene granulite and is mainly composed of two pyroxenes, plagioclase, amphibole and biotite. Its melano-minerals are rich in Mg/(Mg+Fe^2+),and its amphibole and biotite are rich in TiO2. The AG is rich in Mg/(Mg+Fe^2+), Al2O3 and depletion of U, Th and Rbcontents. The AG has moderate ∑REE and LREE-enriched with weak positive Eu anomaly. The AG shows island-arc pattern with negative Nb, P and Ti anomalies, reflecting that formation of the AG may be associated with subduction. Geochemical and mineral composition data reflect that the protolith of the AG is calc-alkaline basalt and formed by granulite facies metamorphism having peak P-T conditions of 750℃-780℃ and 0.6-0.7 Gpa. The AG formation underwent two stages was suggested. In the early stage of oceanic crustal subduction, calc-alkaline basalt with island-arc environment underwent granulite facies metamorphism to form the AG in deep crust, and in the late stage, the AG was thrust into the upper crust. 展开更多
关键词 岩石学 地球化学 地球动力学 基性麻粒岩 新疆北部地区 阿尔泰造山带
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A Novel Distributed LDoS Attack Scheme against Internet Routing 被引量:3
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作者 ZHU Hongliangt XIN Yang +1 位作者 WU Qiuxin YOU Fucheng 《China Communications》 SCIE CSCD 2014年第A01期101-107,共7页
关键词 DOS攻击 LDO 互联网 分布式 路由 TCP协议 BGP协议 拒绝服务
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关于摄象机校正和PnP问题区别的一点讨论 被引量:2
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作者 孙凤梅 《自动化学报》 EI CSCD 北大核心 2005年第3期402-405,共4页
The camera resection and the PnP problem are both of great importance in computer vision field. However, these two fundamentally different problems are often mistaken one another in the literature. In this short note,... The camera resection and the PnP problem are both of great importance in computer vision field. However, these two fundamentally different problems are often mistaken one another in the literature. In this short note, the essential differences of these two problems are clarified, and such a clarification seems helpful for those who are working on the problems. 展开更多
关键词 PNP问题 摄象机 校正
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Modeling Recrystallization of Austenite for C-Mn Steels during Hot Deformation by Cellular Automaton 被引量:2
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作者 LinZHANG XianghuaLIU 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2002年第2期163-166,共4页
关键词 Cellular automaton RECRYSTALLIZATION Grain size DEFORMATION AUSTENITE
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Preparation and Crystal Structure of Sodium Hydrogen Epoxysuccinate 被引量:2
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作者 李贺敏 朱红军 +2 位作者 金华 马骥 王锦堂 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第3期259-262,共4页
C4H3O5Na(0.5H2O) was prepared by the reaction of H2O2 and maleic anhydride. The product was characterized by elemental analysis and IR measurement. The crystal structure was determined by single-crystal diffraction ... C4H3O5Na(0.5H2O) was prepared by the reaction of H2O2 and maleic anhydride. The product was characterized by elemental analysis and IR measurement. The crystal structure was determined by single-crystal diffraction analysis. The crystal belongs to monoclinic, space group C2/c with a = 21.132(3), b = 8.646(2), c = 6.196(1) ?, β = 90.67(1)o, V = 1132.0(4) ?3, Mr = 163.06, Dc = 1.914 g/cm3, Z = 8, F(000) = 664, μ = 0.243 mm-1, the final R = 0.0354 and wR = 0.1151. X-ray analysis reveals that there exists a stable symmetrical structure in the complex, and a network structure is formed via intermolecular hydrogen bonds. 展开更多
关键词 sodium hydrogen epoxysuccinate PREPARATION crystal structure
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Quasi-Optical Cavity Virtual Cathode Oscillator for Microwave Generation 被引量:1
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作者 凌根深 陈波 周津娟 《Chinese Physics Letters》 SCIE CAS CSCD 2003年第11期1977-1980,共4页
A new configuration of a virtual cathode oscillator (VCO), i.e., a quasi-optical cavity VCO, is proposed for high-power microwave generation. The analysis and simulation are carried out to investigate the characterist... A new configuration of a virtual cathode oscillator (VCO), i.e., a quasi-optical cavity VCO, is proposed for high-power microwave generation. The analysis and simulation are carried out to investigate the characteristics of thisconfiguration. In the numerical simulation, the microwave output power of 2.93 GW is obtained with an electronbeam of 610 keV in electron energy and 26.7kA in the beam current. The beam-to-microwave power efficiency is18%. The frequency is 17.5 GHz, and the output microwave mode is TEM10. 展开更多
关键词 虚拟阴极振荡器 VCO 结构 准光学腔 微波产生 数值模拟 电子能量
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Assessment on Different Schemes of Industrial Structure Adjustment Based on DEA 被引量:2
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作者 FULi-fang MENGJun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2004年第1期93-96,共4页
DEA is a new research field in operations research. It has unique virtues in dealing with assessment problem with multi-inputs especially multi-outputs. In this paper, DEA model of D?着C2R has been applied to evaluate... DEA is a new research field in operations research. It has unique virtues in dealing with assessment problem with multi-inputs especially multi-outputs. In this paper, DEA model of D?着C2R has been applied to evaluate the relative efficiency of several different schemes of industrial structure adjustment of agriculture and finally select the optimal scheme. Furthermore, the inferior scheme has been improved according to some useful insights got from DEA model. 展开更多
关键词 industrial structure adjustment of agriculture DEA DEA efficient
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INTERVAL ADJUSTABLE ENTROPY ALGORITHM FOR A CLASS OF UNCONSTRAINED DISCRETE MINIMAX PROBLEMS 被引量:6
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作者 LiSubei CaoDexin +1 位作者 WangHaijun DengKazhong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2004年第1期37-43,共7页
In this paper,a class of unconstrained discrete minimax problems is described,in which the objective functions are in C 1.The paper deals with this problem by means of taking the place of maximum entropy function... In this paper,a class of unconstrained discrete minimax problems is described,in which the objective functions are in C 1.The paper deals with this problem by means of taking the place of maximum entropy function with adjustable entropy function.By constructing an interval extension of adjustable entropy function an d some region deletion test rules,a new interval algorithm is presented.The rele vant properties are proven.The minimax value and the localization of the minimax points of the problem can be obtained by this method. This method can overcome the flow problem in the maximum entropy algorithm.Both theoretical and numerica l results show that the method is reliable and efficient. 展开更多
关键词 discrete minimax problem adjustable entropy function interval algorithm .
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Topological Structure of Disclination Lines in 2-Dimensional Liquid Crystals 被引量:1
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作者 张慧 杨国宏 《Journal of Shanghai University(English Edition)》 CAS 2002年第3期207-210,共4页
Using mapping method and topological current theory, the topological structure of disclination lines in 2 dimensional liquid crystals is studied. By introducing the strength density and the topological current of m... Using mapping method and topological current theory, the topological structure of disclination lines in 2 dimensional liquid crystals is studied. By introducing the strength density and the topological current of many disclination lines, it is pointed out that the disclination lines are determined by the singulaities of the director field, and topologically quantized by the Hopf indices and Brouwer degrees. Due to the equivalence in physics of the director fields n (x) and n (x) , the Hopf indices can be integers or half integers, representing a generalization of our previous studies of integer Hopf indices. 展开更多
关键词 topological current winding number director field disclination line.
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