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A single observer location method under the scatter signals position disturbance situation:the constraint total least square method

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Science china(Information Sciences) 2011年第1期54卷 146-152页

作者： YANG TianChi1,YU ChaoQun2.WANG TianPeng1 & JIN Liang1 1National Digital Switching System engineering and Technological Research Center, zhengzhou {2.china 2.urveying and Mapping college of Information engineering university, zhengzhou {2.china 1. National Digital Switching System engineering and Technological Research Center Zhengzhou 450002 China2. Surveying and Mapping College of Information Engineering University Zhengzhou 450002 China

A target position can be estimated using position information from scattered signals in the nonline-of-sight propagation environment in a single observer location *** is always an error in the final estimated result of the position obtained using scatter signals because measurement noise is *** reduce the total error of the system,we propose a method of converting the problem of optimizing location into a one of solving the extremes of the *** the problem of how to solve the extremes of the constraints is converted into an unconstrained problem by using the constrained total least squares(CTLS) ***,the Newton iteration method is used to obtain the optimized *** results also verify the capability of this method.

关键词： scatter position disturbing VOCTLS single observer location Newton iteration

Dynamic Tensile Properties of Concrete under Different Environments

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Journal of Wuhan university of Technology(Materials Science) 2006年第4期21卷 163-168页

作者：闫东明 School of civil and Hydraulic engineering Dalian University of Technology Dalian 116024 ChinaSchool of Environment and Water Conservancy Engineering Zhengzhou University Zhengzhou 450002China

By using an MTS810 hydra-electro-servo universal machine, the effect of moisture content and temperature on the rate sensitivity of concrete was irwestigated, the range of strain rate was varying from 10^- 5 / s to 10^-0.03/s. It is coneluded from the tests that the water content has a significant influence on the rate sensitivity of concrete whereas the tempature has a slight one, and the effects of rate sensitivity are attributed to both the viscosity caused by free water and the transformation of fracture mode when subjected to a high strain rate. The dynamic strength, initial modulus of elasticity, critical strain, Poisson ratio and energy absorption properties were studied systematically. It is found that the strength, initial modulus of elasticity, critical strain, and energy absorption capacity of concrete all increase with the increasing strain rate, whereas Poisson ratio keeps almost unchanged.

关键词： strain rate tension moisture content fracture mechanism

Controlled free radical polymerization of styrene initiated from the alkoxyamine-functionalized silicon surface

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Science china Chemistry 2005年第5期48卷 449-458页

作者： CHEN Zhijun1, ZHOU Sikai1, LU Wenzhong1, FANG Shaoming1, JIANG Xiqun2.& YANG Changzheng2.1. college of Materials and Chemical engineering,{2. of Light Industry, zhengzhou 450002. china 2. Laboratory of Mesoscopic Material Science and Department of Polymer Science & engineering, college of Chemistry & Chemical engineering, Nanjing university, Nanjing 2.0093, china 1. college of Materials and Chemical engineering Zhengzhou University of Light Industry 450002 Zhengzhou China 2. Laboratory of Mesoscopic Material Science and Department of Polymer Science & engineering College of Chemistry & Chemical Engineering Nanjing University 210093 Nanjing China

We describe a new method of fabricating a brush-like polystyrene layer anchored on the surface of the silicon substrate, which involves three steps, namely (i) the attachment of 3-methacryloxypropyltrimethoxysilane onto the silicon surface; (ii) the reaction of vinyl moiety at another extremity of the anchored 3-methacryloxypropyltrimethoxysilane to 4-Hydroxyl-2. 2. 6, 6-tetramethyl-1-piperidinyloxy (HTEMPO?) catalyzed by azobisisobutyronitrile (AIBN); (iii) living free radical grafting polymerization of styrene in the presence of HTEMPO?. The controllable living free radical polymerization permits accurate control of both the molecular weight and the polydispersity. X-photoelectron spectroscopy measurement proved that the alkoxyamine initiator layer forms on the silicon surface. XPS and Ellipsometry measurements showed that the poly-styrene chains were covalently anchored onto the silicon surface. The thickness of the grafted polymer layer can be accurately manipulated by altering the polymerization time. The new method allows synthesizing random copolymer and block copolymers by the sequential growth of monomers from the substrate surface.

关键词： polymer brush, controlled living free radical polymerization, thickness, atomic force microscopy, 3-methacryloxypropyltrimethoxysilane.

Dynamic Properties of Concrete under Severe Environmental Condition

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Journal of Wuhan university of Technology(Materials Science) 2010年第5期25卷 877-882页

作者：闫东明 Department of Hydraulic and Environmental engineering Zhengzhou University Department of civil and Hydraulic engineering Dalian University of Technology

Exposure to environmental conditions can significantly influence the mechanical behavior of concrete structures in civil engineering. In this study, the effect of environmental factors, such as moisture and temperature, on the strain-rate sensitivity of concrete mixtures was systematically investigated. The strain rate varied from 10^-5s^-1 to 10^-2.^-1. From the investigation it was concluded that moisture content had a significant influence on the strain-rate sensitivity of concrete. With regard to concrete with low moisture content, temperature had little influence on the rate-dependent behavior; while for fully saturated specimens, a significant influence was observed. These phenomena were attributed to the meso-scale bonding properties of the concrete matrix. Equations were derived to characterize the ultimate strength increment of concrete with strain rate under different environmental conditions. An explanation to the dynamic failure mechanisms of concrete based on the experimental findings was proposed.

关键词： concrete strain rate moisture content temperature failure mechanism

A relationship between the nonexistence of generalized bent functions and class groups

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Science china Mathematics 2010年第1期53卷 213-222页

作者： LIU FengMei 1,& YUE Qin 2. Department of Information Research,college of Information engineering,Information engineering university,zhengzhou 450002.china 2.Department of Mathematics,Nanjing university of Aeronautics and Astronautics,Nanjing 2.0016,china 1. Department of Information Research College of Information Engineering Information Engineering University Zhengzhou 450002 China2. Department of Mathematics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

A new result on the nonexistence of generalized bent functions is presented by using properties of the decomposition law of primes in cyclotomic fields and properties of solutions of some Diophantine equations. At the same time,a method is given which can be used to simplify the known results. Then we give the bounds and the meaning in algebraic number theory of the parameters in our results.

关键词： generalized bent function integral basis class group genus theory

SYNTHESIS AND CHARACTERIZATION OF ORGANOMONTMORILLONITE AND POLYAMIDE 66/MONTMORILLONITE NANOCOMPOSITES

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Chinese Journal of Polymer Science 2002年第6期20卷 551-557页

作者： Cheng-shen Zhu Xin Kang Su-qin He Liu-yang Wang Li-yun Lu college of Materials engineering,{2. university, {2. 450052. china zhengzhou Univ Coll Mat Engn Zhengzhou 450052 Peoples R China

The montmorillonites (MMTs), layered, smectite-type silicates, were premodified by two different methods prior to the polymer melt intercalation. In one case MMTs were modified with cetyltrimethylammonium bromide (CTAB), and termed as organomontmorillonites (OMMTs); in the other case MMTs were modified by nylon, and the products were called modified montmorillonites (MMMTs). The effects of CTAB and nylon on the MMTs were investigated by using TG and WAXD. The results show that interlayer spacings of CTAB and nylon modified MMTs are larger than that of sodium MMTs. Then, polyamide 66 (PA 66)/MMT nanocomposites were obtained through the method of melt intercalation of polymers. The nanocomposites were characterized by WAXD, TEM and Molau experiments. The results indicate that the MMTs disperse homogeneously in the PA 66 matrix. The mechanical properties of nanocomposites, such as tensile properties and flexural properties, were also measured and show a tendency to increase with increase of MMT content and reach the maximum values at 5phr MMT content. The heat distortion temperature (HDT) of the nanocomposites (7 phr) is about 32.K higher than that of pure PA 66.

关键词： montmorillonite polyamide 66 nanocomposites melt intercalation

A new orthogonality relationship for orthotropic thin plate theory and its variational principle

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Science china(Physics,Mechanics & Astronomy) 2005年第3期48卷 371-380页

作者： LUO Jianhui 1 , LONG Yuqiu 2.& LIU Guangdong 1 1. college of civil {2., Hunan university, Changsha 410082. china 2. Department of civil {2., Tsinghua university, Beijing 100084, china 1. college of civil {2. Hunan University 410082 Changsha China 2. Department of civil engineering Tsinghua University 100084 Beijing China

The thought how dual vectors are constructed in a new orthogonality relationship for theory of elasticity is generalized into orthotropic thin plate bending problems by using the analogy theory between plane elasticity problems and plate bending problems. Dual differential equations are directly obtained by using a mixed variables method. A dual differential matrix to be derived possesses a peculiarity of which principal diagonal sub-matrixes are zero matrixes. Two independently and symmetrically orthogonality sub-relationships are discovered. By using the integral form for elastic bending theory of orthotropic thin plate the orthogonality relationship is demonstrated. By selecting felicitous dual vectors a new orthogonality relationship for theory of elasticity can be generalized into elastic bending theory of orthotropic thin plate. By using the integral form a variational principle which is relative to differential form and a whole function expression are proposed.

关键词： theory of elasticity, thin plate theory, dual vectors, orthogonality relationship, orthotropic, variational principle.

Hybrid particle swarm cooperative optimization algorithm and its application to MBC in alumina production

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Progress in Natural Science:Materials International 2008年第11期18卷 1423-1428页

作者： Shengli Song~(a,b) Li Kong~a Yong Gan~b Rijian Su~(a,b) a Department of Control Scienee and engineering,Huazhong university oF Science and Technology,Wuhan 430074,{2. b college of Computer and Communication engineering,zhengzhou university of Light Industry,zhengzhou 450002.{2. Department of Control Science and engineering Huazhong University of Science and Technology Wuhan 430074 China college of Computer and Communication engineering Zhengzhou University of Light Industry Zhengzhou 450002 China

An effective hybrid particle swarm cooperative optimization(HPSCO)algorithm combining simulated annealing method and sim- plex method is *** main idea is to divide particle swarm into several sub-groups and achieve optimization through coop- erativeness of different sub-groups among the *** proposed algorithm is tested by benchmark functions and applied to material balance computation(MBC)in alumina *** show that HPSCO,with both a better stability and a steady convergence,has faster convergence speed and higher global convergence ability than the single method and the improved particle swarm optimization *** importantly,results demonstrate that HPSCO is more feasible and efficient than other algorithms in MBC.

关键词： PSO Simulated annealing Simplex Cooperative optimization

Expansive Behaviors of Self-stressing Concrete under Different Restraining Conditions

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Journal of Wuhan university of Technology(Materials Science) 2011年第4期26卷 780-785页

作者：常旭 college of civil {2. Henan Polytechnic University

The expansive behaviors of the expensive concrete under different restraining conditions were systemically studied. The experimental results indicate that expansive deformation obviously increases before 10 days and tends to be constant after 2. days regardless of the restraining conditions. The mixture ratio of expansive cement and restraining conditions are the main factors affecting expansive deformation. Self-stress can be obtained when the expansive deformation is restrained. The higher self-stress could be obtained when the expensive concrete is restrained by steel tube. For specimens under steel tube restraining, the wall thickness and the length of the steel tube have important influence on self-stress. Both the radial self-stress and axial self-stress in concrete core increase when wall thickness or length of the steel tube increases.

关键词： self-stress expansive concrete restraining condition