Assembly design of pipeline system of working style refueling equipment is very complex because of the similarities and differences of assembly structure of pipeline system in different assembly spaces. Clustering method of assembly space of pipeline system based on hierarchical clustering method was proposed to solve the problem mentioned above, and each category of clustered assembly space could use many same sets of assembled piping system. By defining typical assembly space and assembly radius, the assembled pipeline system which met the requirement could be found quickly according to the assembly space size when a new project was designed. Lastly, examples like clustering in some typical assembly space and the application of clustering results, were used to illustrate validity and rationality of the proposed method．

In view of incomplete consideration to maintenance correlation with traditional methods, a new opinion was put forward to judge maintenance correlation in a multi-unit system from four aspects such as time correlated, fault correlated, structure correlated and function correlated. As the degree of maintenance correlation ultimately affects and decides the contents of maintenance combination in a multi-unit system, it was weighed by the optimized effect of maintenance combination in a multi-unit system. On these bases, the correlation degree of multi-component maintenance could be evaluated by using matrix permanent, which takes indicators and the relationship between indicators into account during the process of evaluating multi-component maintenance correlation. The example showed that it could help maintaining workers to judge maintenance correlation and comparing with the correlation degrees of maintenance parts in multi-component system by the analysis and evaluation. Meanwhile, it proposed the optimal maintenance combination through maintenance correlation degrees in a multi-unit system．

In order to decrease the impact and vibration induced by impact roller during its working, the characteristics of influence of the cushioning system's parameters on the impact load acted on the tractor were studied by simulation. The dynamic equations of cushioning system were established through analyzing the structure and work performance of the impact roller. The solid model of the whole machine was set up in UG software and was transformed into ADAMS that is multi\|body dynamic simulation software. The dynamic model was established with the tire and the road, and the dynamic characteristics of the whole machine were simulated under typical work conditions. The simulation results were compared with test data, which validates the correctness of the simulation model. Utilizing parametric design research method, the model was parameterized and the variations of traction load were simulated and analyzed when the system's stiffness and damping parameters changed. The sensitivity curves and load curves were achieved and the rational ranges of parameters were presented. The results show that the first level damper and the second level stiffness have much greater effect upon the traction load than the other parameters, and the whole machine's simulation model is able to simulate the work condition of impact roller and provides the references for eng

The motion characteristics of all spring-type vibration device for continuous casting mold was researched. The equivalent spring mechanism and equivalent linkage of all spring-type vibration devices for continuous casting mold were built based on theory of mechanism and mechanics of materials. Kinematics simulation of them were done with the Simulink simulation software. The comparative analysis of simulation results verifies modeling and movement characteristics analysis of the leaf spring-type mold vibrator body is valid, which provides a method and technology accumulation for the design and analysis of the vibration device of the whole spring-type continuous casting mold.

A complete geometric and force model for five-axis flank milling was presented, and then geometric simulation and cutting forces prediction can be conducted based on the integrated model. Feedrate scheduling was planned based on the mechanistic model. The method selected for geometric stock modeling was the dexel approach. The cutter workpiece engagements defined the instantaneous intersection boundary between the cutting tool and the in-process workpiece. From the CWE, the cutter entry-exit angles and depth of cuts were found and used to calculate the instaneous cutting forces. The constrained optimization was solved by sequential quadratic programming and the machine was operated at threshold levels. The process was optimized by varying the feed as the tool-workpiece engagements vary along the tool path, and the research provided a powerful tool for analysing five\|axis flank milling. Production time in flank milling dual blades was reduced considerably to 40% with the satisfaction of precision demands．

The method to build a finite element model for the pick cutting rock was discussed. The single pick on the cutting heads of longitudinal\|axis roadheaders cutting rock was simulated. The finite element model was built in hypermesh, and solved by the LS_DYNA971. The influences of resistance on different cutting angle and the relations between cutting thickness and cutting energy consumption in different cutting angle were discussed, which were also compared with the commonly used formula of the pick cutting resistance. Simulation results show that bond\|graph modeling approach is feasible and correct. Further more, The optimal pick angle of small wearing and small cutting resistance is found. And the relations between cutting thickness and cutting energy consumption were found. So, the whole result provides a new way in the field of dynamic modeling and simulation for pick cutting rock．

An accurate finite element method was set up for analysis of contact-impact characteristics of trilobe equidistant polygonal connection. In this method, the profile curves were fit through cubic spline curves, and 3D FEM model of shaft-hub coupling was adopted. The analysis of nonlinear 3D contact-impact characteristics of trilobe equidistant polygonal connection was taken to simulate the startup process of coupling. The variation of contact force and maximum effective stress during the startup process could be extracted through a calculating example of the trilobe equidistant connection. The results can be further applied to study the influence of different structural parameters and operating parameters on contact-impact characteristics. The result of the analysis shows that 3D analysis is more effective in simulating the real situations than the 2D analysis,and adopting no clearance fit or interference fit can restrain impact effect of the polygonal connection,and enlarging the eccentricity ratio can also enhance the anti-compact performance and the carrying capacity effectively.

As clearance exists in kinematics pair of clearance contact and collision, the modeling and computation would be very complicated. According to the specific property of kinematics pair, contact forces were divided into three states and damping forces were divided into two states. Based on the analysis the bond graph model was established by introducing the concept of switched power junctions. Taking a geneva mechanism for an example, the bond graph model of the contact pair between roller and ring race was set up and simulated by advanced software 20-sim. Finally, the results, compared with those from ADAMS to check the bond graph model, verity its credibility.

In the development stage of aluminum-alloy wheel, the bending fatigue test is one of the bench tests that must be passed, to which the trial casting wheel on a small batch basis was put. To avoid experiments of blindness, reduce the number of tests, cut down the experiment cost and improve the reliability, the finite element method is applied, which is one of the advanced technologies in design stage. To apply the technology correctly, the effective calculation model must be built to simulate bench tests. Based on the theoretical analysis and practical case, considering the nonlinear contact relations from pretightening of blot and the material of difference between loading bar and wheel, three finite element models of bending fatigue tests were built, such as integral linear elastic model with loading bar and wheel in the same material, the separated linear elastic model with loading bar and wheel in different material, the nonlinear model considering with the affection of contact relations and pretightening force. According to analysis and confrontation, and verification test oriented with the typical wheel, theirs advantages and shortages, stress range and computing reliability were studied; the veracity of models was verified with the test of a typical wheel. The research shows the nonlinear load model is corrected, the linear elastic model can be used to analyze the fatigue of wheel which is easy to be broken near bolt hole, and the same\|different material of loading bar and wheel is less influential on the most equivalent stress, and the nonlinear contact model, considering with the affection of contact relations and pretightening force, was applicable to the analysis of the wheel which is easy to be broken near bolt hole．

A new method for computing reliability sensitivity of multi-parameters influential mechanism was presented. The model of mechanism was built by
using multi-body system dynamics theory and Kriging method. On this basis, we can get the
reliability sensitivity. Using this method the experiment has overcome the difficulty
caused by the model of complex mechanism, especially the mechanisms that performance
functions can not be calculated. At the same time, Monte Carlo simulation was used in this
method, which helped us to get the input and output of the Kriging model by small scale of
sample. As shown in the example, the method is efficient and easy to use, and it also
provides us a theoretical basis for the design.

In order to meet the need for online accuracy wall thickness measurement of seamless tubes, the authors discussed a technology of wall thickness measurement based on generalized cepstrum. The disadvantages of correlation in wall thickness measurement were analyzed. A measuring method based on generalized cepstrum was presented. It integrated the advantages of correlation analysis and cepstrum. The accuracy was highly improved. Further more, the authors compensated the online error caused by the rotation of the tube. The experimental results show that the proposed method has the characteristics of high precision and strong real-time, which is suitable for the online industrial wall thickness measurement of seamless tube.

In order to realize image processing in the application of surface defects, and replace the traditional way of manual inspection, the authors have developed a metal surface defect detection system to study the nickel-plated hardware online image processing algorithms, including edge detection algorithm, the position correction algorithm, calibration algorithm and detection algorithm, bringing hardware visual surface defect detection into effect. At the same time, the authors proposed a threshold feedback algorithm, and used the actual defect theory of defects in the value of feedback verification, and ultimately got reliable defect threshold to determine surface defects. The detection system can use multi-surface and multi-station movement work piece simultaneous independent detection.

In order to meet the needs of high-precision and real-time target information extraction from micro-vision images in the micro-nano and biological fields, a kind of real-time segmentation method of micro-vision images with uneven illumination based on multi-resolution threshold was proposed. Because the traditional methods are difficult to estimate the threshold accurately in micro-vision image with uneven illumination and consume too much time, firstly, the energy function of gray intensity distribution was established according to the sparseness property of the gradient probability distribution, and the optimum gray intensity distribution was estimated by applying the iterative re-weighted least squares (IRLS) technique for the purpose of uneven illumination compensation in micro-vision image. Secondly, on the basis of the traditional two-dimension Otsu method, multi-resolution analysis of wavelet transform was employed to reduce effectively the computation of threshold estimation process and improve real-time segmentation of the micro-vision images. Experimental results showed that the proposed method possessed the fast and precise segmentation performance, which was also free of the uneven illumination effect and able to coordinate effectively the contradiction between the accuracy and speed of segmentation．

The waveguide power divider has been widely used in many microwave and millimeter-wave systems as a key element in multiplexer, coupler and antenna feeding system etc. Embarked from the principle of work in rectangular waveguide power divider, the theory and design rules of SIW(substrate integrated waveguide) power dividers was researched by use of SIW's advantages such as high Q-factor and low-cost etc. An X band 4-way SIW power divider was designed, and the measured results show that the returned loss of the power divider is lower than -15 dB from 9.0 GHz to 11.0 GHz, which corresponds to 20% bandwidth. And the measured S₂₁  to S₅₁  in the pass-band fluctuate between -9.0 dB and -7.7 dB, which could meet the design requirements. This power divider can be widely used in microwave circuits, and suitable for mass production because of its low cost and simple structure.

Many fields require a stringent measurement precision of the speed test systems increasingly, and ask a harsher requirement for light curtain speed test system at the same time, which is a kind of common speed test systems. In order to improve the measurement precision of the speed test system based on infrared light screen,a speed test system based on infrared ray-photoelectric switches and NI6220 DAQ was introduced, which may take the place of the traditional DAQ system based on the SCM, and improved the reliability and measuring precision of speed test system. Working principles, structure design and software design based on LABVIEW were introduced,and the system errors also were analyzed. Experimental results prove that this method can ensure the test error in less than 0.0156%,when the speed is slower than 1 000 m/s．