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According to the different engine materials and mechanical properties, we use sound spectrum detection methods to check mechanical noise. We design a system to monitor the consistency of the engine material mechanical properties. The system should be prior to detect and store the object sound spectrum characteristics, then according to the typical standard parts, do a lot of experiments through the frequency-domain analysis algorithm. The experimental results show the system has the very good identification characteristics for source frequency relatively stable mechanical system. So the system in the product identification, design, consistency evaluation plays an important role.

In this paper, a novel yellow-emitting oxynitride phosphor Sr3-2xSiO5-6xN4x: yCe3+, yLi+ (0 x 0.33, 0.01 y 0.04) has been reported. The XRD patterns illustrate that the partial substitution of (SiN)+ for the (SiO)2+ is feasible and the major phase of synthesized samples is isostructural with Sr3SiO5. Under blue light excitation, the oxynitride phosphor shows a broad emission about 557 nm, contributing to the 4f5d transition. The PL intensities show a blue shift as the increase of nitrogen content (the locations of peaks move from 559 nm to 549 nm).

A method to analyze the shape of three-dimensional curve surface for flexible rolling forming metal plate is proposed based on the traditional rolling and multi-point adjustment technology. It has smaller rebound and better forming in comparison with the traditional method which is using the surface deformation. The simulation experiments are implemented using the developed experimental device to demonstrate the feasibility and practicality of the flexible rolling forming. The proposal could be used in the various industries.

The structure of the wind turbine generator system is complex and it is difficult to identify the fault signals because of fault frequency aliasing on the vibration characteristics. The wind turbine fault diagnosis method is raised on single component shock to solve the vibration signal feature extraction during the wind turbines operating. Based on the principle of Hilbert envelope demodulation, this envelope demodulation method is presented for the single IMF component which contains shock fault characteristic frequency to solve the possible problem which fault Frequency is difficult to identify when the original signal is directly asked to envelope. This method has been applied and verified when a wind farm CSC-855W wind turbine vibration monitoring device was presented. The results show that compared with the traditional envelope demodulation method, by this method wind turbine fault characteristic can be more effectively and directly extracted and the accuracy of fault diagnosis can be improved. It is of great practical value.

Robot motion accuracy plays a vital role in the production which makes use of industrial robots. This paper takes advantage of iterative algorithm to calibrate the robot joint parameters on the basis of setting up mathematical models of 6-DOF robot crossed technology on the mathematical model. It puts forward the method obtained by measuring the pose compared with the theoretical and the robot absolute posing deviation. It provides the basis of surface sheet metal precise scribing work on the next stage.

With increasing of high pressure, the performances of all kinds refrigerants except for R744 are all declined, transcritical R744 compression cycle has an optimum high pressure. With increasing of the evaporating temperature, all cycle COP is an increasing trend, with increasing of outlet temperature of condenser, the performances of all cycles are decreased. Under the same comparison conditions, the performance of R22 refrigerant cycle is superior to the cycles of other refrigerants, and the cycle of R11 refrigerant has the worst performance.

Based on the analysis to the geometric relations of eccentric slider-crank mechanism (ESCM) at two limiting positions, a new and simple graphic method for design of ESCM was proposed in the paper. The method has the characteristics of legible concept, concise operation and good practicality. Utilizing the new method, the ESCM could be designed quickly under given conditions (slider stroke H, coefficient of travel speed variation K, the auxiliary conditions such as the length of crank a, length of connecting rod b and deflection distance e) without any calculation. Meanwhile, under given conditions (H, K) the alternative region of crank fixed center A, the possible feasible regions of crank length a and deflection distance e were discussed.

The Various methods of optimization or random search have been developed for locating the critical slip surface of a slope and the related minimum safety factor in the limit equilibrium stability analysis of slope. But all these methods are based on a two-dimensional (2D) method and no one had been adapted for a search of the three-dimensional (3D) critical slip surface. In this paper, a new Monte Carlo random simulating method has been proposed to identify the 3D critical slip surface, in which assuming the initial slip to be the lower part of an ellipsoid, the 3D critical slip surface in the 3D slope stability analysis is located by minimizing the 3D safety factor of limit equilibrium approach. Based on the column-based three-dimensional limit equilibrium slope stability analysis models, new Geographic Information Systems (GIS) grid-based 3D deterministic limit equilibrium models are developed to calculate the 3D safety factors. Several practical examples, of obtained minimum safety factor and its critical slip surface by a 2D optimization or random technique, are extended to 3D slope problems to locate the 3D critical slip surface and to compare with the 2D results. The results shows that, comparing with the 2D results, the resulting 3D critical slip surface has no apparent difference only from a cross section, but the associated 3D safety factor is definitely higher.

The fatigue crack growth behavior of weld joint of Q460NH steel is very important for estimating life-time in terms of a crack length in weld joint. In this paper , fatigue crack growth behavior of weld metal (WM),heat affected zone(HAZ) and mother metal(BM) have been researched at room temperature. The variation of fatigue crack growth rate(da/dN) with stress intensity factor range (ΔK) for WM, HAZ and BM is discussed within the Paris region. It is shown that fatigue crack growth rate of WM is the slowest in tree parts .

By using ABAQUS software to conduct numerical simulation and model test of pile-bucket under mono-loading of up-pulling force and horizontal force, then make comparison of both results to testify the accuracy of finite calculation model. Then by numerical simulation to study bearing capacity of pile-bucket foundation under combined loading of up-pull and horizontal force. The result shows the pile-bucket foundation horizontal displacement will increase with the increase of up-pulling force at the limit horizontal load, and the horizontal displacement becomes more obvious as the up-pulling load increasing if providing greater horizontal loading force. Before the up-pulling force reaches the limit, horizontal load will not affect up-pulling displacement; after the up-pulling force reaches the limit, the horizontal load can slightly reduce the up-pulling displacement of pile top. The effect of up-pulling load increase on horizontal displacement is obvious for pile depth in soil at 0~15m, but very tiny for pile body with buried depth over 15m.

The coarse grain heat affected zone(CGHAZ) at different parameters t8/5 of high-strength bridge steel Q460q were simulated with thermal simulation machine. the microstructure of CGHAZ and the effect of granular bainite on the toughness were analyzed in this paper.The results show that: When t8/560s, the quantity of eutectoid ferrite and granular bainite increased, coarse M-A constituent resulting in the grain size of effective crack propagation becoming coarser and toughness decreased significantly.

The welding cold cracking tendencies of Ca microalloyed HSLA steel was evaluated using crack sensitivity index Pcm, oblique Y-groove cracking test and the hardness of simulation CGHAZ(coarse grain heat affected zone) in this paper. The organizational structure and mechanical properties of simulation CGHAZ at different t8/5 was analysised in this paper two. The results show that:steel welding cold crack is less sensitive; the CaO pinning austenite grain boundaries effectively, fining the grain size of CGHAZ, increasing the amount of IFA, and improving the toughness of CGHAZ.The weldability of Ca microalloyed HSLA steel is good.