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To reveal the fault occurrence regularity during actual operation of transport vehicle, based on reliability, maintainability and optimization theory and method, and by the the technical means such as large sample testing, mathematical modeling and multivariate data analysis, after several years of follow-up research, we found that the occurrence of vehicle failts obey Weibull distribution, and given specific failt rate functions. Accordingly, we established a corresponding optimal mathematical model of vehicle maintenance cycle, and got the optimal solution of the model. The results of special organized verify test shows that the model solution is accurate and reliable. If transport vehicles perform the optimal vehicle maintenance cycle, the lowest unit mileage cost of vehicle detection, diagnosis and maintenance would be got.

Mortarless interlocking blocks have the advantage of convenient construction and low cost, but establishing the geometry interlocking mechanism between horizontal blocks has been overlooked. Optimizing the shape of mortarless interlocking block. The connection of vertical direction in the form of a frustum of a cone, and the connection of horizontal direction in the form of trapezoid shape. This design proposal builds geometry interlocking mechanism between the block and its all adjacent ones. Setting cone and rectangular holes on block body, accordingly, block laying could forming taper vertical channel and rectangular vertical channel. The concrete of interlocking mortarless block has particularity, which is not suitable for “Mix Proportion Design of Ordinary Concrete Regulation” (JGJ55-2010) of China. This paper presents a platter idea to establish the concrete mix proportion design method of mortarless interlocking block, moreover, an example calculation and confirmatory experiment is dispensable.

In order to realize the large field or view digital video images into PAL format analog video output,this article introduce a real-time display system of large visual field in the basis of FPGA. Apply the EP2S30F672I4 chip of the StraixII series to be the core processing unit, which is from the Altera; and the CSC12M25BMP19 camera, from the Teli, to be the image data source, with 25 Hz of output frame rate and a resolution of 2048 x 2048 on images. The Cameralink interface is adopted to be the data transmission channel between the camera and interface card, which carries out the configuration of the camera, image data acquisition, caching, image reduction and PAL format conversion, and finally accomplishes the image real-time display.This paper discusses the FPGA implementation of double bilinear interpolation algorithm, including image data frames buffer, the vertical and horizontal interpolation. The experiments results show that our expects are achieved by the algorithm and the hardware implementation.

This paper study the acoustic signal characteristics of coal and rock mass under uniaxial compression by the tests of acoustic emission(AE),which obtain the variation of AE counts and energy.Compressing on original data use wavelet analysis,and extracting the characteristics of signal with the wavelet sym-basis,then decomposing and remodeling the wavelet coefficients,the negative singularity degree indicators of adjacent scales can be got.The results showed that the wavelet transform modulus maximum used to identify the negative singularity degree can achieve the position of the frequency changes point of the acoustic signal,which is of certain guiding significance for prediction of the uniaxial compression process.

The fractional dynamics equation of a viscoelastic two-member truss system, in which fractional derivative model introduced to simulate the materials’ characteristics, is proposed. The equilibrium paths under vertical loads, horizontal loads and combined loads are discussed respectively. The results show that: there are primary and secondary equilibrium paths under vertical and horizontal loads. Bifurcations will occur under combined loads and the ultimate bearing capacity of the system will reduce. The equilibrium paths became complex because of the horizontal disturbance, and the bigger of the horizontal disturbance the smaller of the system ultimate bearing capacity.

A digital regulator architecture implemented in FPGA is described which is used in the accelerator power supply. To save the delay time, the device is based on combinational circuit and special data format. The multiplier uses the partial products generated by modified Booth algorithm, Carry look-ahead adder and Wallace tree. The regulator is written in Verilog, and is synthesized into FPGA. The synthesis results shows that the proposed regulator can run 200MHZ clock rate in FPGA EP3C25F256 and the whole feedback time is as short as 3 clock periods.

A series of supported catalysts Co3O4/SiO2 were prepared by deposition precipitation method. ICP-AES, XRD and TEM data revealed that the Co3O4 active site was highly dispersed on the surface of SiO2. The catalysts were evaluated for selective epoxidation of styrene with molecular oxygen. The results showed that the catalysts were of good catalytic activity for styrene epoxidation and many factors had an evident effect on the catalytic epoxidation activity. The best catalyst was 3% Co3O4/SiO2 on which 96.3% conversion of styrene and 52.7% selectivity of styrene oxide were obtained under the flow rate of O2 20mL/min, 100°C, 10h with solvent.

To analyse and research the idle hydrocarbon emission regularity of passenger car gasoline engine, based on large sample detected data of different type cars, parameter estimation and hypothesis test are carried on by statistical tools and neans, and the optimum distribution parameters of idle hydrocarbon emission of different type engines are also got. Then the optimum distribution models of these engines are established. The calculating result shows that the maximum error between model calculating and sample detecting certification rates is only 0.526 8%, and the established models have very high calculating precision and practical value. On the other hand, the research also shows that the inspect and maintenance program should be strengthen in order to control vehicle emission pollution effectively.

Au/Co3O4catalysts were prepared by a co-precipitation method and characterized by inductively coupled plasma-atomic emission spectrometry (ICP-AES), transmission electron microscope (TEM) and X-ray diffraction (XRD). The selective oxidation of cyclohexane to cyclohexanone and cyclohexanol was investigated over Au/Co3O4catalysts using molecular oxygen as oxidant. These catalysts showed higher activities as compared to the pure Co3O4under the same reaction conditions.

Alumina was modified by doping with metal oxide and then used as the support for depositing gold by an impregnation-ammonia washing method to obtain Au/MxOy/Al2O3(M=Co, Zr and Ce) catalysts. These samples were characterized by inductively coupled plasma-atomic emission spectrometry (ICP-AES), transmission electron microscope (TEM) and X-ray diffraction (XRD). The effects of Co3O4content, metal oxide and mixed metal oxides on the catalytic activity for the selective oxidation of cyclohexane to cyclohexanone and cyclohexanol using molecular oxygen as oxidant were studied. The results showed that better catalytic performance was obtained over Au/MxOy/Al2O3catalysts compared with over Au/Al2O3catalysts. 9.69% conversion of cyclohexane and 93.31% selectivity to cyclohexanone, cyclohexanol and cyclohexyl hydroperoxide, with 1.02 ratio of cyclohexanone to cyclohexanol were obtained over the Au/MxOy/Al2O3catalyst at 150 , 1.5 MPa for 3 h. Moreover, according to the recycling test, the catalyst could be reused four times without remarkable loss of activity.

In order to utilize the waste steel slag effectively, three kinds of alkaline activator such as Na2SO4, Na2SiO3, Na2CO­3 were used to prepare steel slag cementitious material and measure its strength of 28 days and 60 days in the standard wet conditions. Microcosmic structure form of hydration products of cementitious material was analyzed by the test of SEM. The results indicate that: three activators on the strength of steel slag all have certain stimulation effect, and Na2SO4 has the apparent stimulation effect on the strength of steel slag, the analysis and test of SEM also shows that hydration products structure form of steel slag cementitious material added with Na2SO4 is much more than other two activators and is more helpful to improve steel slag strength.

Carbon-supported gold catalysts Au/C were prepared by an impregnation-reduction method and modified by AgNO3to obtain bi-metallic catalysts Au-Ag/C, which were characterized by X-ray-diffraction (XRD) and Transmission Electron Microscope (TEM). Their catalytic performance was tested in the oxidation of cyclohexene in an autoclave without any solvent. The results showed that Ag doping can significantly enhance the catalytic performance of carbon-supported gold catalyst. Au(1.0 wt.%)-Ag(1.0 wt.%)/C has been found to be an efficient catalyst for the cyclohexene oxidation with a conversion of 27.6% at 80 °C and 0.4 MPa for 12 h while selectivity for ∑C6products (including cyclohexene oxide, 2-cyclohexene-1-ol, 2-cyclohexene-1-one and cyclohexane-1,2-diol) exceeding 88.9%, especially the selectivity of cyclohexane-1,2-diol up to 47.6%. Moreover, the effects of Au, Ag content on catalytic performance were also reported.

With wide applications of FRP in civil engineering, it is necessary to study the durability of FRP reinforced concrete structure. Based on the related research both at home and abroad, the factors affecting durability of FRP reinforced concrete structures and the corresponding improvements have been put forward by analyzing the durability of concrete, FRP materials and reinforced structures, respectively.

At present, only the temperature of external surface of the filament wound composite and the core mode can be detected in the curing process which is developed by experiencing many times, and the change of the internal parameters is not available. Based on the glass fiber pipe production line as the experimental platform, the paper suggests that the fiber grating sensors be embedded fiber composite materials at different levels when winding and the multipoint detection be performed in the internal curing process. The comparison analysis of the plotted curves for data collected from different points shows that the method is reliable to improve production efficiency and promote the automation of intelligent control.

Multi-axis winding machine can realize automatic winding of composite elbow, but its mechanical structure and control system is complex, which restricts its industrial application. In this paper, two-axis FRP elbow winding machine applied teaching and playback method is designed, which accomplish the winding of elbow by controlling the rotation motion of the mandrel and the reciprocating motion of the carriage along a semicircular track. In teaching mode, the positions of spindle and carriage are collected and stored as teaching document when the spindle rotates a certain angle, while in playback mode the control method of electronic cam is applied to realize the playback winding. The mechanical structure and the working principle of elbow winding machine are introduced, and the control system of winding machine is analyzed. It is proved that the system is stable, and it can wind certain type of composite elbows.

The external curing method is usually adopted as the traditional molding process of thermoset fiber composite shell, which places the wound shell into the thermal compression reactor or the oven to cure. This kind of process greatly limits the molding efficiency because winding and curing proceed respectively and separately. The internal curing can be adopted because of the hollow structure of the cylinder-shaped shell, which heats the mandrel with high pressure steam to realize the in-situ curing of the wound shell. This paper researches the new fiber composite molding process named heated mandrel winding. Not only does the heated mandrel winding inherit the advantages of internal curing process, it also greatly improves molding efficiency and quality. This paper introduces the process principle of heated mandrel winding and uses the finite element analysis software FLUENT to carry out the numerical simulation of steam flow and heat transfer during the mandrel heating process, and the simulation results are verified by experiment. According to the simulation results, the distribution and changing course of the flow field and temperature field of the system are obtained, and the relationships between the physical quantities including pressure, temperature and velocity and the parameters of the steam control and channel structure are analyzed.

Wavelet analysis has become a popular subject in scientific research in the past twenty years. In this work, we develop the concept of a class of vector-valued multivarition matrix. A new method for constructing multidimensional vector-valued wavelet packets is formulated. Their characteristics are researched by means of operator theory, time-frequency analysis method and matrix theory. There orthogonality formulas regarding the wavelet packets are provided. Orthogonality decomposition relation formulas of the space L2(Rs)r are obtained by constructing a series of subspaces of the vector-valued wavelet packet. Furthermore, several orthonormal wavelet packet bases of space L2(Rs)r are constructed from the wavelet packets.