Key Engineering Materials Vols. 467-469

Abstract: The new generation leveler control system need to deal with amounts of data. Directed at the characteristics, this article demonstrates the structure design of its database architecture. From the communication interface, hardware and software environment, functions, technologies, etc., we expounded the implementation of database system, such as real-time database, alarm database, model material databases, historical database, and safety information database and so on. It shows that the database system is a core of new generation leveler control system. We also present specific examples of design and give the detailed method of approach.

Abstract: Dent is one of the important factors affecting pipeline fatigue life, and it will greatly reduce the fatigue life of the pipeline in service. Based on a large number of foreign dented pipeline fatigue test results and fatigue life model, for the typical dent defect, using finite element method, various parameters are changed and finite element models are obtained under different conditions. According to many calculation results, a key ratio of peak period stress and pipeline pressure variation are obtained, which are substituted to the fatigue life model and the example are calculated.

Abstract: Because the thrust and suspend stability is related to sine level of air gap magnetic field, so the sine level of air gap magnetic field is the point of it’s operational factors, proposed a optimization function of magnetic field based on the simplex method, and the optimization design of the stage is established. The main magnetic parameter is assured, and step response is attached, the result is expressed that the magnetic stage is finished the nm position requirements.

Abstract: The increasing P2P network traffic on the Internet has leaded to the problem of network congestion. In the consequence of the diversification of the P2P business and protocol, research on the management of P2P traffic has many problems to resolve. Prediction of the P2P traffic is the kernel problem in the P2P traffic management. Based on the existed P2P traffic characters, this paper structures a P2P traffic model, gives a traffic prediction algorithm bases on wavelet-analysis, and proves the accuracy of the algorithm. Simulation experiment figures that the algorithm has a high prediction precision and a superior real-time performance.

Abstract: To simplify the operation for the oil and gas development for drill and complete the well in the petroleum industry, a natural vegetable gum drilling and completion fluids system is developed for the industrial control and application. As the system combines the advantage of the drilling fluid and completion fluid, it need not change the two different fluids during the operation, which is beneficial to the operation control. In addition, it can improve the implementation of the oil and gas exploration for industrial application. An extensive laboratory work for the high-temperature resistance capability of the natural vegetable gum drilling and completion fluids system is carried out, including the formulation study of the detailed system and the corresponding performance evaluation. In the system, with the basic formula of the natural vegetable gum drilling and completion fluids system, several new formulas beneficial to improve the high-temperature resistance capability of the system have been described. The corresponding laboratory analysis has demonstrated that the prosperities of the system, with the temperature resistance capability up to 305℉, are proper for the industrial application.

Abstract: A kind of 2-DOF parallel manipulator driven by two sliders moving along two parallel guides is analyzed. Based on the explicit expression of inverse position, velocity and acceleration analyses, the mobile trajectory of this manipulator is investigated and simulated. In trajectory planning, the trajectory profiles are assigned to be accelerated and decelerated at the first and last few seconds, respectively, and keep at constant speed for the remainder of time, where the forth-order polynomial is fitted during acceleration and deceleration, and clothoid curve is applied around the corner of axis. Then the mobile rule exerted on the actuator sliders is obtained using inverse position based on the desired end-effecter trajectory. Finally, the virtual prototype of this mechanism is modeled using Solidwork and the kinematics and dynamics simulation is performed using Cosmostion. The result shows that both velocity, acceleration of the sliders and the driving force exerted on the sliders are continuous curves, which can fully satisfy the demand of high-accuracy and real-time processing of the high-speed Manipulator.

Abstract: Numerical simulation is an effective method for predicting formability of metals, and the use of computer simulation enables a significant increase in the number of tool designs that can be tested before hard tools are manufactured. Based on dynamic explicit finite element software, finite element simulation of sheet metal forming was performed to investigate the applicability of applying hydrostatic pressure on blank in multi point discrete dies. Simulation results show that using the hydrostatic pressure on blank is apposite for the process of multi point discrete dies.

Abstract: In this paper, we propose a human-attention driven video capture method for wearable visual computing. This method could help wearable vision system to avoid collecting a lot of meaningless visual images and save the platform resources. We firstly calculate background similarity and recognize user’s attention behavior, then detect user’s active or passive attention status, finally automatically and selectively capture video information according to user’s attention interest. We describe architecture of proposed method and give an experiment to validate its feasible.

Abstract: Based on the finite element analysis software ABAQUS, the CT specimens of bimetallic material and the metallurgical composite bimetallic pressure tube with axial crack were simulated on the fracture mechanical properties, after that the crack growth residual strength and the plastic failure stress of the metallurgical composite bimetallic pressure tube model were obtained. The results indicate that the crack growth residual strength generates near the crack tip and the crack growth residual strength of the pressure tube model is smaller than the CT specimens. Meanwhile, the plastic failure stress values obtained from the CT specimens and the pressure tube model are basically consistent with the theoretical calculative values. With the crack depth a increasing, the plastic failure stress values will be reduced. For the same crack depth, the plastic failure stress values of the pressure tube model are slightly lower than the CT specimens and the theoretical calculative values.

Abstract: This article uses the finite element software ABAQUS in the process of laser cladding to form the numerical simulation, which establishes numerical simulation model of the temperature field of laser cladding forming the heat transfer. The results show that the laser scanning position of the cladding layer depth direction of a high temperature gradient. Simulation of temperature changes of a known point the temperature change in laser scanning region is drastic. The experimental results show that the numerical simulation model of the temperature field is reasonable. Therefore, the numerical simulation model can be used to analyze the influence of the laser cladding parameters on the temperature field and simulate remelting depth under any scanning speed.