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Multi-ribbed slab structure (MRSS) is a new structural system developed in recent years, with multi-ribbed slab wall as its main bearing member, which was an orthogonal anisotropic solid constituted by reinforced concrete ribs, frame and embedded solid body. It was suggested to employ asymptotic expansion-based homogenization method to establish the equivalent homogenized model. The method is that it considers the impact of rib relative width and the possion. The research results showed that: the macroscopic constitutive relationship of multi-ribbed wall based by the method has certain accuracy, can provide basis for multi-ribbed slab structure FEM analysis.

Based on the differential equation for buckling of deep and long foundation pile, considering the effects of side friction of pile, foundation soil horizontal tension and pile weight. Then the equation is solved by Galerkin Method, the buckling critical load and effective length equation of deep and long pile foundation is deduced. At the same time, the main parameters’ effect to pile buckling stability is analyzed. At last, a practical example is presented, and the calculated result is compared and proved to be feasible.

In this paper, AHP method is used as an researching tool, to build the supplier performance evaluation system including quality, cost, delivery and service, development and technology, management and communication. The supplier evaluation system is built by setting up the evaluation standard and calculating the weight of different indicators. This system would be a reference for enterprise supplier management.

In this paper based on the foundation construction of Datong Xian high-speed railway, a large number of test samples have been taken. The order and contribution rate of every experiment factor like cement commingle ratio, depths, water dipping conditions, compacting factor and vibration frequency on the dynamic characteristics of cement-improved loess such as dynamic elastic modulus, dynamic deformation, damping ratio by dynamic triaxial test, which orthogonal test method has been applied to. The dynamic load was calculated according to the train vibration attenuation rule of different depth. The dynamic characteristics of cement-improved loess such as dynamic deformation, dynamic elastic modulus, damping ratio were got form the dynamic tests of long time and large number of cycles. The results showed that with the increase of cement ratio, the dynamic characteristics of cement-improved loess are more better, there is no optimal ratio of cement.

Single wall carbon nanotubes (SWNTs)/chitosan (CS) composite was synthesized by electrostatic interactions between positively charged CS and negatively charged carboxylic group-functionalized SWNTs. The SWNTs/CS composite was characterized by using scanning electron microscopic and electrochemical analysis. The experimental results show that the SWNTs/CS composite is stable and homogeneous and has excellent electrochemical property.

Perpendicularity error has great influence on the quality and performance of the geometrical products, and it is of great importance to guarantee the interchangeability. Particle swarm optimization (PSO) is an extraordinarily useful intelligent optimization algorithm with several advantages of fast convergence rate and easy realization for computer in the multidimensional space function optimization and dynamic target optimization. As a result, it is very accurate and is accordant with the requirement of minimum zone method (MZC) using PSO to associate the base plane of perpendicularity error.

In this study, molecular dynamics (MD) simulation has been employed to investigate the distribution function of gyration radius under different temperatures. The structure of chloroprene rubber (CR) was constructed and the circles of energy minimization were applied. The fitting functions of normal stress with time under different pressures were obtained. Compression stress relaxation experiment of different temperatures was also conducted. Comparing with the coefficient of stress relaxation from the experiment, it was found that the theoretical stress relaxation results were similar to the experimental data. The results indicated that the mean-square radius of gyration decreased with reduction of temperature, which corresponded to the typical viscoelasticity stress relaxation behaviors of polymers. It is confirmed that the variation of mean-square radius can be used to quantitatively describe the stress relaxation of rubber system and a good agreement between the theoretical curves with the experimental data can be obtained from MD simulation.

Angularity is an important parameter to evaluate the position precision. According the new generation of GPS, a new method of evaluating plane to plane angularity error based on coordinate rotation was proposed. In the process of evaluation, first the datum plane is associated by the minimum zone method; and then the datum plane is transformed into the ideal coordinate system plane. Based on the ideal datum, the plane is obtained by coordinate rotation; angularity error value is the maximum distance subtracts the minimum distance that measured points to the plane. The measurement for a V-groove in arbitrary position is performed on a three dimensional coordinates measuring machine; the result shows that angularity error can be evaluated effectually and accurately using this algorithm.