Advanced Materials Research Vols. 311-313

Abstract: The controlled object of boiler combustion system in power plant is a complex system with nonlinear, timing change, large lagging and multi-variable coupling, and does not have precise mathematical model, so it is difficult to obtain the satisfactory control effect adopting the traditional PID control. Advanced control strategies are adopted to improve the performance of the boiler combustion control system, and it has been more and more the concern of the majority of electricity production enterprises. Internal model control is a very practical control method, and its main characteristic is simple structure, intuitive design and few online adjustment parameter, and easy adjustment policy. And it is especially particularly significant to improve the control effect of large delay system. The internal model control system is used in power station boiler combustion system, it can effectively solve the large delay, large inertia and other shortcomings, but there is the contradiction between the fast response and robustness in internal model control system. The fuzzy immune control has advantages, such as, fast response, fast stable and good robust, etc. The fuzzy immune control is introduced into internal model control system, this paper designs fuzzy immune internal model controller, which integrates speed and robustness of the internal model control. The fuzzy immune internal model control is applied to combustion control system, and we compare it with ordinary internal model control method. The simulation result shows that fuzzy immune internal model control can greatly improve the characteristics of the control system with time delay. And this effectiveness of the fuzzy immune internal model controller has been verified.

Abstract: Shape memory alloy was firstly used commercially as a hydraulic coupling in the Grumman F14A in 1971. It is today used among others to improve structural behaviours such as buckling of composite plates in the aerospace vehicles. In this paper, finite element model and its source code for thermal post-buckling of shape memory alloy laminated composite plates is presented. The shape memory alloy wires induced stress that improved the strain energy, stiffness and thus the buckling behaviour of the composite plates. The finite element formulation catered the combined properties of the composite and shape memory alloys, the addition of the recovery stress and the temperature dependent properties of the shape memory alloys and the composite matrix. This study showed that by embedding shape memory alloy within layers of composite plates, post-buckling behaviours of composite plates can be improved substantially.

Abstract: Manufacturing process is more assisted by improvement projects to improve efficiency or decrease cost. These project teams usually cross different departments so engineers need to know coordination needs while executing such projects. This study examined twelve manufacturing process improvement projects to analyze coordination needs and their relationships with project performance. The results indicate that the project’s uncertainty is generally higher than equivocality. But it is equivocality that has a correlation with performance. This finding means that adequate adoption of coordination methods to decrease equivocality will have impact on project performance. While comparing the projects with higher equivocality, the major difference is resulted from environment quality and personnel differences.

Abstract: This study presents the development of a MR damper applied to the suspension of tracked vehicles to improve the ride comfort and mobility. The MR valve is constrained to a specific cylindrical volume in order to keep the same geometry with the original damper. Radial duct is selected for its high efficiency and small volume requirement. The design rule is to enlarge the dynamic force range of the damper under the condition that the off-state force accords with the fail-safe principle. So the mechanical modeling is established and the influencing factors of adjustable coefficient are analyzed so as to determine the geometry parameters of MR valve. A set of experiments are performed to verify the theoritical analysis. The experimental results illustrate the designed MR damper has a good performance of energy dissipation and can be used to practical applications.

Abstract: The best is to read these instructions and follow the outline of this text. Mg-RE-B alloy with minuteness particle structure (MPS) were prepared by ingot metallurgy including as-cast and hot-extruded processing, and the microstructure and mechanical property of Mg-6RE-3B2O3 (wt%) alloys were investigated before and after hot-extruded. The Mg-RE-B alloy has satisfied grain size and particle structure, went with excellent mechanical property of tensile yield strength of 520 MPa and elongation of 5% at room temperature. The MPS Mg-RE-B alloy is a promising candidate among lightweight structural materials

Abstract: A brunet reflective exterior wall insulation coating was prepared. The influence of titanium dioxide crystal and particle shape on coating solar reflectance was studied, and the result showed that the coating contains Rutile titanium dioxide has good reflective performance. The influence of non-ferrous pigment on coating reflective properties was studied. Among these pigments, the reflectivity of iron oxide red which has darker color is comparatively higher, and has good compatibility with coating system. It was selected as non-ferrous pigment of this brunet department coating. Iron oxide black and medium chromium yellow was added to mix the coating color, when the dosage of pigment is iron oxide red 3.72%, Iron oxide black 0.036%, medium chromium yellow 0.24%, the coating is brown, and the solar reflectance could reach 80.22%. The basic properties of coating were all conform to the National Standards, and it is a brunet exterior wall coating which has uniform atomization performance and good reflection insulation performance.

Abstract: The giant magnetostrictive material (GMM) in dynamic magnetic field has nonlinear and hysteretic characters. Based on the nonlinear constitutive model of the material, the quasi-static hysteresis model with magneto-elastic coupling was built on the Jiles-Atherton model. Considering the eddy current and anomalous losses, the hysteresis model was modified, and the dynamic coupling hysteresis model was established on the basis. Compared with the experimental data, the areas of hysteresis curves increased with frequency, and the maximum magnetostriction strain of the curves increased with prestress. The model agreed well with the experiments within the range of 500Hz.

Abstract: Submicron-sized monodisperse and spherical poly(N-isopropylacrylamide-co-glycidyl methacrylate)-β-cyclodextrin (PNG-CD) microgels with both thermo-responsive and molecular-recognition characteristics have been successfully fabricated via soap-free emulsion polymerization and subsequent chemical modification method. The thermo-responsivity of the microgels is based on the volume phase transition of poly(N-isopropylacrylamide) (PNIPAM) and the molecular-recognition property is based on the host-guest inclusion complexation of β-cyclodextrin (β-CD) units with specific guest molecules. The as-prepared microgels are characterized by Fourier transform infrared (FT-IR), scanning electron microscope (SEM), and dynamic light scattering (DLS) instrument. When β-CD is introduced onto the PNG-CD microgels, the volume phase transition temperature (VPTT) of resultant PNG-CD microgels shifts about 6 °C to a higher temperature in comparison with that of corresponding PNG microgels. When the β-CD units in PNG-CD microgels recognize 8-anilino-1-naphthal-enesulfonic acid ammonium salt (ANS) molecules in aqueous solution, the VPTT of PNG-CD microgels shifts around 3 °C negatively to a lower temperature. PNG-CD microgels present molecular-recognition induced swelling characteristics at fixed temperature. The results in this study provide valuable information for development of monodisperse and spherical dual thermo-responsive and molecular-recognition microgels which have potential applications in the fields of microscale molecular sensors and actuators and so on.

Abstract: The characteristic vector of cylinder vibration signal is extracted by wavelet packet decomposition. The factor of selection is proposed to take adaptive integration on basis of improved super parent one dependence estimator Bayesian method and back propagation genetic algorithm neural network method. Experimental results on WD615 diesel engine showed that the method has high accuracy rate of detection.

Abstract: This paper presents a transformation kinetics model of NiTi shape memory alloy (SMA) wires based on electrical resistivity (ER) derivative study under the assumption that the derivative of electrical resistivity with respect to temperature is in linear relationship with the derivative of free energy change with respect to temperature. Free energy change and electrical resistivity properties of SMA are analyzed based on differential scanning calorimetry (DSC) experiments during phase transformation. The simulated evolution of electrical resistivity during thermomechanical transformation is presented using the proposed model.