Abstract:The shear responses of reinforced concrete beams strengthened with HPFL were experimentally investigated. In the test, six restrained RC beams strengthened with HPFL and three control specimens without strengthening were used. At the same time, seven simply supported beams under point concentrated load with one unstrengthened and nine simply supported beams under two points concentrated load with three unstrengthened were included. The beam performances were compared and assessed with particular emphasis on cracking behavior and shear capacity. The results have shown that HPFL can obviously increase the crack-resisting capacity and the shear resistance of beams. The recommended formula of shear resistance of beams strengthened with HPFL was proposed on the basis of the experimental research. The calculated values have good agreement with the test results. Combining the test data with the standard named Technical Specification for Strengthening Concrete Structures with High Performance Ferrocement Laminate, the standard formula and engineering sample calculation were introduced in the text.

Abstract:The relations between the minimum horizontal reinforcement ratio of wall with strength grade of block, mortar, reinforcement and vertical compressive stress were analyzed on the basis of research results abroad. The variant scope of minimum horizontal reinforcement ratio during normal service was derived. It coincides with the current code stipulation. Simplified formula of minimum horizontal reinforcement ratio for wall with ductile shear failure has been provided. At the same time, vertical compressive stress dominant scope is proposed when minimum horizontal reinforcement is needed. This research result can be used as a reference in design.

Abstract:The splitting fatigue tests of three types of AC25 asphalt concretes under freeze-thaw and without frozenthaw condition were carried out. The gradations of aggregate in asphalt concretes were coarse, medium and fine. The stress and strain fatigue equations were obtained with the result of the tests. The effect of water, temperature, load and their coupling action on the fatigue life were studied. The results are as the following: the fatigue life of asphalt concrete is in good relation to its split strength, the lower split strength of the asphalt concrete, the lower fatigue life. According to fatigue life, the gradations of different asphalt concretes from best to worst is as follows: rough, fine and medium. The effect of temperature on the fatigue life of asphalt concrete is not obvious in strain control mode test, and the strain fatigue equations at different temperatures can be given with a single equation, which interprets that the process of strain fatigue for asphalt concrete has nothing with temperature. The fatigue life of unfrozenthaw coarse asphalt concrete reduced in a large scope as the increases of temperature. When subjected to a freezethaw cycle, the fatigue life for different types of asphalt concretes reduce about 10% to 35% in the same stress ratio, while it reduce about 75%～80% in the same stress level.

Abstract:To make rational use of geometric and physical information of slope, and to control the influence of the outliers on deformation parameter estimator, a constrained filtering model using mechanical state information of slope was given. The model integrates statistical information about observation and information about mechanical state and geological conditions of slope. The algorithm given makes full use of geophysical model information to eliminate the influence of abnormal observation and improve the precision of deformation parameter estimator.

Abstract:20 series of empirical parameters were obtained by applying optimal Latin Hypercube method in Isight, and then the external flow field around Ahmed model was simulated with these parameters in Fluent. On this basis, Kriging model was used to create approximate model. Taking the results from wind tunnel experiments as the optimization goal, the empirical parameters in the Realizable kε turbulence model were optimized with the Multiisland Genetic Algorithm. Finally, these parameters were applied to the development of some real road vehicles, and were verified with the wind tunnel experiment. The results have shown that, by using the optimized empirical parameters, the contour of velocity from simulation is much closer to that of the experiment, and the drag force coefficient error also decreases by 2.8% with fast convergence velocity.

Abstract:A method was proposed to improve the singularity condition of the reduced basis method in the rapid analysis of solid structures. This method examines and deals with the response basis which corresponds to the sample points in the parameter domain, and eliminates the highly linearly dependent vectors. Subsequently, the newly obtained basis is conducted by reduced QR factorization, and Galerkin projection is then performed onto the space spanned by the column vectors of the matrix 〖WTHX〗Q. Therefore, the proposed method can enhance the computational accuracy and reliability. The numerical example has demonstrated this result.

Abstract:In order to analyze the driving characteristics of tractorsemitrailer with the lateral degrees of freedom, a system dynamic model including body rolling and stiffness of steering system was established. Simulations were done under some typical operating conditions. Then, the traction saddle parameters were debugged and well extracted, and the system stability was investigated under the influence of these parameters, which provided reference for the designer. The changes of driving conditions and parameters of the traction saddle could cause body rolling and coupling angle and should be judged with the parameter sensitivity analysis. Simulation results have shown that the model can be applied to analyze vehicle characteristics appropriately.

Abstract:Based on energy conservation law, and combined with system dynamics and hydromechanics, the mathematical model of the Hoffmann Hydraulic Mechanism (HHM) was established in the chamber method. Then, the RungeKutta method was selected to solve the state equations. At last, with the SIMULINK in MATLAB, the dynamic characteristic of this system was analyzed, and the oil pressure changing with time was investigated. Both are of considerable significance for the system characteristic study and design improvement.

Abstract:Multiple lowpass filter (LPF) with fuzzy reasoning was established, and a detecting algorithm based on S. Fryze, F. Buchholz, M. Dpenbrock (FBD) method was proposed for active power filter (APF). Reference voltage was generated by phaselocked loop(PLL), and load current was projected to reference voltage, and then active power fundamental current and reactive power fundamental current could be detected accurately. The multiple LPF composed of two twoorder Butterworth LPFs was developed on the basis of fuzzy control, and the fuzzy controller was designed by taking into account the changing amplitude of load current and the lowest harmonic current. Compared with traditional current detecting algorithms, this new reference current detecting algorithm based on FBD method is much simpler and of higher accuracy and better dynamic performance even under unbalanced voltage circumstance. Theoretical analysis and MATLAB simulation results have proved the validity and effectiveness of the proposed reference current detecting algorithm.

Abstract:Investigation of upconversion on nanocrystal and bulk La2O3 : (Yb3+, 1mol%Er3+ ) prepared by combustion and solid phase reaction was reported. Under 980 nm LD excition, predominant green upconversion(around 545 nm) in the bulk and strong red upconversion emission (around 660 nm) in the nanocrystal are obtained at room temperature. Under the same condition of measurement, the upconversion efficiency of the nanocrystal is lower than that of corresponding bulk, which mainly originates from the twophoton process for the nanocrystal and from energy transfer process between Yb3+ and Er3+ ions for the bulk.

Abstract:The surface acid electroless nickleplating technology on quartz fiber was studied, and the factors affecting the surface appearance of nickleplating layer were investigated. The research results have shown that the optimum temperature of sensitization and activation for quartz fiber is about 35 ℃.And the optimum plating conditions are as follows: the density of NaH2PO2·H2O is 0.2 mol/L ,the proportion of nickle ion in nickle liquid and NaH2PO2·H2O is 0.35, the pH is 4.8,and the plating temperature is 88 ℃. In the conditions of optimized process, it has been found that it is unnecessary to coarsen fiber in the process of prehandle for continuous plating layer. The nickle layer obtained was uniform, continuous, bright and subtle, and has good adhesive force from the quartz fiber without coarsening, and the coating rate is 5.76 μm/h.

Abstract:Cucoated graphite powders were fabricated by ultrasonic flow plating．The effects of electroplating parameters on the copper content in Cucoated graphite powders were investigated. The results showed that uniform and dense Cu coating was electroplated on graphite powders and there was 50%～75％ copper content in Cucoated graphite powders. Cugraphite brush was made of Cucoated graphite powders, which possessed lower resistivity and better wear resistance than that obtained by mixing copper and graphite powders mechanically.

Abstract:The solubility of the KCl-K2SO4-H2O system was simulated at a wide range of temperatures by using PSC model and Pitzer model. The experiment water activity and experiment solubility in the binary KCl-H2O, K2SO4-H2O and ternary KCl-K2SO4-H2O systems were used to obtain the model parameters. For the KCl-K2SO4-H2O system of low solubility, the Pitzer model values are in agreement with the experiment data just by using binary coefficients, and the PSC model should take into account the ternary coefficients.

Abstract:Bioleaching heavy metal from mine tailings has been widely accepted. In this study, the bacteria indigenous Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans isolated from an acidic mine tailings dam were grown and acclimated in presence of mine tailings and then used as bioleaching bacteria to solubilize the mine tailings. After 12 days of bioleaching, the laboratory results of the experiment demonstrated that the indigenous bacteria had high value of bioleaching. And the percentages of copper and zinc solubilized into the leaching solution from tailings basically increased with the optimal bacteria. The percentage of Zn solubilized is 98.12% when indigenous Acidithiobacillus ferrooxidans are used as bioleaching bacteria. The percentage of Cu solubilized is 88.75% when the mixture of indigenous Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans are used as bioleaching bacteria.

Abstract:The particle concentration distribution characteristics of black smoke in a canopy dust catcher were numerically simulated with FLUENT software. The effects of the particle diameter (0.24~11 μm), inlet dust loading (1~7 g/m3) and inlet velocity (10~16 m/s) on the particle concentration profile were calculated with selecting Reynolds stress model (RSM) and Discrete phase model (DPM) as gas phase model and particle phase model, respectively. Simulation results showed that the particle concentration of black smoke in a canopy dust catcher was radially distributed into lowconcentration in the middle areas and highconcentration near the wall. In the same radial cross section, the particle concentration increased with the rise of inlet dust loading, and decreased with the increase of particle diameter and inlet velocity. Furthermore, the simulation results agreed well with the experiment data. The relative error of the pressure drop was less than 6%. These results will provide a basis for the building of a perfect umbrella cover dust model.

Abstract:The fairness to share bandwidth in open access network was discussed. The maxmin fair algorithm was used in the dualSLA bandwidth share algorithm. The dualSLA schedule algorithm was easy to implement. The user SLA was the primary SLA and the service provider SLA was the secondary. It can satisfy the fairness request for both the service provider and the user through the bandwidth adjust algorithm. The experiment result has shown that the algorithm is feasible. The fairness to share bandwidth of the user and the service provider was well realized.

Abstract:A template matchbased method was presented by using the contours of image sequence as representative descriptors of human posture to achieve human action recognition. First, the entire binary image of human silhouette was obtained by background subtraction and shadow elimination from video sequences. A new contour descriptor was defined, which was employed to transform the contour into a 1D distance signal. An approximating polygon was constructed by connecting the neighbor segmenting points by using line segment after equally segmenting the contour and the centroid of silhouette was obtained. The three distance strings formed with the distance from the vertexes to the center of contour and the distances from the vertexes to the two subsequence vertexes were used to describe the contour. A hierarchical clustering method was proposed to extract the key postures of human action and a human behavior sequence could be presented by a character string if a key posture was presented by a character. The edit distance was proposed to measure the similarity of the templates and the test sequences. Experiment results have shown that this method can achieve a correct recognition rate of above 85.7 %.