Applied Mechanics and Materials Vol. 274

Abstract: The finite element modeling and experimental validation of three-dimensional heavy cutting of high strength steel (2.25Cr-1Mo-0.25V) are presented. The commercial software Deform 3D applied for the finite element modeling is studied the effect of feed rate on the principal cutting forces and the temperature fields. The friction between the tool and the chip is assumed to follow a shear model and the local adaptive remeshing technique is used for the formation of chip. The feed rate significantly affects the cutting forces, but slightly influences the maximum temperature of the chip. The simulation results are compared with experimental data and found to be in good agreement.

Abstract: Based on the study of ergonomics, this paper summarizes morphological characteristics of computer numerical control machine tool modeling, and according to the work functions and operation characteristics, it gives an analysis of the principles and requirements of computer numerical control machine tool modeling design and ergonomics, which will help broaden our thoughts in designing more vivid, lively and rapid new computer numerical control machine tool modeling.

Abstract: Selecting accurate hydraulic conductivity is critical to calculating correctly seepage field. Because of geotechnical hydraulic conductivity with spatial randomness and its errors in measurement and computation, the extended Kalman filter (EKF) is proposed to its back analysis. In conjunction with the finite element method (FEM) of seepage, details of the EKF are introduced in this paper. With FORTRAN programs, the hydraulic conductivity is revised according to the real-time monitoring data during tunnel excavation, and illustrates the EKF merits of considerable convergence and tolerable accuracy.

Abstract: The steering ratio of vehicle can be changed by attaching a angle, Changing the steering gear ratio can improve the safety in high-speed and comfort in low-speed and the vehicle steering stability. The paper introduces an active front steering system (AFS) based on harmonic drive, the composition and working principle of the system are analyzed, and the kinematic analysis of the system is researched, finally, the self-control mechanism and integrated control mechanism with other stability system are studied.

Abstract: The phenomenon of the piston jitter during charging and discharging test with the 80kpa for the spinning brake cylinder is been studied and the corresponding measures for improvement is been carried out. The tests show that the phenomenon of piston vibration is disappeared after the measurements are adopted.

Abstract: Reducing the overall cost and improving the reliability are two primary but often conflicting objectives for composite generation and transmission system . Scheduling of appropriate preventive maintenance requires optimization among multiple objectives. In this paper, a systematic and integrated methodology with three functional blocks is proposed. In the first block, the stochastic deterioration process of individual components is formulated as a continuous-time Markov model, in which transition rates incorporate the influences of the aging of components and two (minor and major) maintenance extents. Reliability of a composite generation and transmission system is dependent upon its topology as well as its load and generation profiles, and is evaluated in the second block. In the third block, Pareto-based multi-objective evolutionary algorithm is proposed because of its proven ability to search towards the optimum among a large number of potential solutions for providing a holistic view of conflicting relationships among multiple objectives. The proposed approach is applied to the IEEE reliability test system (IEEE-RTS), and the reliability, maintenance and failure costs of the entire IEEE-RTS are optimized. The successful application to IEEE-RTS demonstrates its potential of handling complex systems.

Abstract: The IDEF0 method can comprehensively and clearly describe the production line design data streams, the material streams and the relationship among the function activities, may guarantee the standard design and lay the solid foundation for the system implementation smoothly. Using the IDEF0 method to describe the function of the production line design flow, it can satisfy this complex large-scale system analysis and design request. It aims at optimizing the manufacturing of automotive parts to be more scientific and consecutive.

Abstract: It is first to make Empirical Mode Decomposition (EMD) and achieve Hilbert-Hung transform (HHT) of envelope spectrum after Hilbert transformation, which can resolve the cross fault existing in Hilbert transformation is utilized merely. However, it can’t improve the resolution of envelope spectrum, which doesn’t adapt the characteristic of high resonant frequency of rolling bearing and low fault frequency. The paper utilizing the principle of real modulation shift frequency moves the EMD decomposition components of high frequency section to low frequency section and makes analysis of envelope spectrum after Hilbert transformation, which resolves the problem of low frequency resolution of pure HHT.

Abstract: This article describes the process design of machining of CNC carved glass-ceramic, which overcomes the question that the traditional process is difficult to process glass-ceramic. Process includes the choice of cutting tools, grinding wheel, coolant, tooling design and roughing finishing etc. It has a certain reference value for glass-ceramic processing technology.