Advanced Materials Research Vols. 753-755

Abstract: Based on the construction features of the steel structures of a type of electrical dust precipitator, a finite element model is established with large-scale finite element analysis software ANSYS, and the structure stress and displacement of the model under all sorts of loads are analyzed with the frontal solution method. The results indicate that analysis is relatively accurate, the finite element model and the analysis method is appropriate. The result can be further used for optimization design of the electrical precipitator steel structures.

Abstract: As an important loading transmitting component in construction and loadout process of offshore structure, skidshoe bears great bending, shearing, pressure and kind of other loadings during its serving period. Based on mechanics theoretic and practical project model, in compliance with related international codes and standards, an analysis tool for skidshoe design is developed in this paper, which utilizes Excel computation sheets powerful data-handling capacity and Visual Basics friendly consistent interfaces. This tool considers typical load conditions for both construction and loadout process in skidshoe analysis.

Abstract: The buckling of the piezoelectric laminated cylindrical shell with throughout circumference delamination is analyzed in this paper. By introducing the Heaviside step function into assumed displacement components and using elastic piezoelectric theory, the constitutive relations of the piezoelectric laminated shell with delamination are established. Then the buckling governing equations of the structure are derived through variational principle. In numerical examples, the effects of delamination length, depth, material property and thickness of piezoelectric layer on the buckling load of piezoelectric laminated shell with delamination are investigated.

Abstract: When a heavy torque load acts on a kind of mechanical gantry, its largest deformation displacement must not be larger than the given upper limit value. So we must make an accurate deformation analysis of the whole structure of the gantry. This paper introduces the analyzing process of the main structure stiffness of the gantry. According to the calculating results , the weak part of structure is found. This part arouses the main deformation of the gantry when loaded. Then a solution is made for it. The stiffness analysis of the gantry is also performed using a FEA software. By comparing the computing results of the two methods, an analysis of the respective computing characteristics and limits of them is given, and a reference for the stiffness analysis of the similar equipments is provided.

Abstract: Riser interference has become a critical issue in riser design with the progression of offshore industry into deep water. It indicates that the potential for interference between Top Tension Risers (TTR) depends not only on the Top Tension Factor (TTF), but also on the riser spacing size. For riser system, each impassive factor of interference could make a different effect (cost and safety), which is often incompatible. A Multi-Objective Optimization (MOO) method is proposed to harmonize the two incompatible objectives: cost and safety. Therefore, it greatly facilitates to adapt the present method to riser interference optimization. Example is given to demonstrate the effectiveness and robustness of the proposed method.

Abstract: The integration method based on network diagram and ant colony algorithm was proposed to realize integration of process routes planning and scheduling. A model of multiple process routes and resource (MPRR) network diagram was built, which applied the network diagram expression and represented the precedence constraint relationship among operations and resource conditions. In the model, the workpiece, operation and machine were joined together as a basic optimization cell to realize concurrent and holistic optimization for process routes planning and scheduling. The combination of MPRR network diagram and characteristics of ant colony algorithm was developed for generating optimal process routes and scheduling project. An example was studied to illustrate the effectiveness of the strategy.

Abstract: Improved clonal selection algorithms and RBF neural network are used for solving nonlinear optimization problems and modeling respectively in iterative learning control, and a nonlinear optimal iterative learning control algorithm (NOILCA) is proposed. In this method, an improved clonal selection algorithm is used for solving the optimum input for the next iteration; another one is used to update the RBF neural network model of real plant. Compared with GA-ILC, NOILCA has faster convergence speed, and is able to deal with the problem of inaccurate plant model, can obtain satisfactory tracking through the few several iterations.

Abstract: In actual welding process, swing welding was a very important way to improve the efficiency and quality of welding. This paper put forward a welding torch swing control system based on the DSP chip TMS320LF2407A, and described its structure, working principle, software implementation and anti-interference design. The control system could realize the swing welding methods set by control panel, control the running motor and swing motor motion, and could realize arbitrary adjustment of the welding torch swing parameters such as speed, amplitude and lag time. On site operation shows that the system is stable, high reliable and meets the demands of industrial field.

Abstract: Considering the problem of optimizing controller parameters for ship rudder roll stabilization when the closed-loop gain shaping algorithm is used to design the controller, a simplex optimization algorithm is proposed. Specially, integral of time multiplied by the absolute value of error (ITAE) criterion is proposed as the performance index for simplex optimization algorithm, and the controller parameters are optimized on-line according to the output of actual system. The optimization of controller parameters are realized by the simplex optimization algorithm, and the results show that the efficiency of setting the control parameters is improved and the roll amplitude is significantly reduced. In addition, the negative influence of rudder roll stabilization to yaw can be also reduced. This method of simplex optimization algorithm provides a new theory for rudder roll stabilization and establishes a theoretical foundation for the application in practical engineering.

Abstract: The current design method of the pot rubber bearing and the existing problems have been analysised.It was ensured that dimension driving method was applied in the SolidWorks modeling driven by Visual Basic. The pre-processing of FEA on the upper bearing plate based on SolidWorks Simulation was ensured, and took the part as an example to show how to use Visual Basic to drive SolidWorks Simulation to realize FEA.