Advanced Materials Research Vols. 308-310

Abstract: The particle sizes of some superfine powders were comparatively determined using Malvern Zetasizer Nano-ZS90 and Omecls-601A laser particle analyzers. The results obtained were analyzed with respecting to the dispersion used, the concentration of particles in the slurry and the particle properties such as their morphology and reflective index. It was found that a conformable result by these two laser particle analyzers can only obtained when the particles were well dispersed in a solution with a suitable content and reflective index as well as low alkalinity.

Abstract: Full consideration and prediction of noise problem of product will be helpful to improve its quality, shorten production period and reduce cost of product. The microperforated panel is a kind of special absorbing material, through proper control of diameter, perforation rate, cavity length , number of panel and so on, the peak value, frequency band of absorption coefficient can be controlled. According to the absorption coefficient characteristics, the microperforated panel can be used to control some special noise structure. Based on the idea, the engineering software matlab is utilized in the paper to simulate the microperforated panel construction to obtain some useful microperforated panel construction for practical noise control.

Abstract: Abstract. Yarn tension controlling at heart is tuning servo-motor speed on a restricted range. In this paper, we proposed an advanced model predictive control strategy to solving filament winding system time-delay problem. The application of controlled auto-regressive integrated moving-average (CARIMA) model was described the dynamic time-varying character. The parameters of CARIMA model were solved by recursive least squares parameter estimation method through input-output data. And using the receding optimization method acquire controlling amount in the future. The result of simulation shows that the method is effective and the control structure is simple.

Abstract: Molybdate conversion coatings were prepared on AZ31B Mg alloy in a molybdate based solution with additives of sodium fluoride (NaF) or lanthanum nitrate (La(NO3)3). The effects of F- and La3+ additives on the morphology and on the corrosion resistance of the molybdate coatings were investigated by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and potentiodynamic polarization analysis. The results revealed that these additives could accelerate the deposition of molybdenum on the surface of AZ31B magnesium alloy. It can be seen that the composite conversion coatings consist of many spherical particles. It is also found that the corrosion resistance is greatly improved after molybdate treatment. The films formed in F- additive solution showed lower corrosion current density than in La3+ additive solution.

Abstract: The nonlinear shear buckling of corrugated steel webs is completed by ANSYS. Consistent mode imperfection method is adopted for simulating corrugation configuration imperfection of corrugated steel plate, shear buckling calculation analysis result shows that ultimate shear buckling load of corrugated steel webs is decreased with increasing in corrugation configuration imperfection. Analysis results shows that oversized corrugation configuration imperfection will decrease the ultimate shear buckling load of corrugated steel webs, but premature buckling caused by steel plate thickness imperfection of corrugated steel webs is much better than plain steel webs, and the ultimate shear buckling load and buckling mode will not be much effected by such steel plate thickness imperfection. On this basis, the influences of corrugation configuration to ultimate shear bucking load and buckling mode are investigated.

Abstract: This paper focuses on an approach to topology optimization and its engineering application. Based on SIMP (Solid Isotropic Microstructure with Penalization) method combined with Guide-Weight method, an approach to solve topology optimization problems is proposed. Then the topology optimization is applied in the design of a key connecting component in a sorghum harvester by the use of proposed method. The derivation process of the iteration formulations demonstrates that the proposed approach has the advantages of easiness to derive and good universality. The result is satisfactory and the convergence speed is fast enough for engineering application.

Abstract: Structural health monitoring is a promising way for evaluating the integrity and safety of large-scale bridges, and crack monitoring is thought to be a challenging problem in this field. An improved design based on smart film for monitoring crack width of concrete bridges is proposed in this paper. Experiments are also implemented to verify the effectiveness of this design.

Abstract: The development process of a glass-fabric composite wind turbine blade is presented. A finite element model is constructed for the design and stress analysis of the wind blade. The wind blade parts were fabricated using the vacuum-bag molding technique. The assembling process of the wind blade is described in detail. The wind blade was tested to validate the suitability of the design. The finite element method is used to predict the failure wind loads of the wind blade.

Abstract: The thesis builds the optimization model for the self-balacing torsion bar, On the basis of the Ant Colony Algorithm, designs the Ant Colony Algorithm procedure using C Language and optimizes torsion bar diameter. Results show the Ant Colony Algorithm is feasible and provides a new method choosing torsion bar diameter. The max difference value is 1.12% between optimizing results and theoretical results.

Abstract: In order to detect litchi fruit under nature scenes, an identification method was studied. A simple process was proposed to segment the image and remove noises. Its key steps include image converting; segmenting by Two-Cluster K-means clustering; labeling by white and black; small noises removing by open-close combined morphology; and big noises removing by blob area thresholding. A new contribution has been made to weighing by ultrasonic sensor and machine vision which allows for identifying litchi weight under nature scenes. A max error of 27% was recorded in tests of such weighing method.