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Aiming at the research status in the field of the equipment maintenance quality evaluation methods, this paper describes the basic type of them in detail, mainly in evaluation mode and arithmetic, points out their characteristic and problems, and analysis and compares them. At last it offers theoretical reference for equipment maintenance quality evaluation methods research.

This paper analyses the necessity of building the evaluating index system for repair quality of representative equipment. This paper studies its repair process, and gives the principle of founding the index system. And then combine with the repair in facts, it establishes the evaluating index system and gives the counting methods and meaning of the basic index at last.

Based on synthesizing the robot’s chassis mechanism,a transformable chassis is presented to adapt to the conflictive requirements of complex fields. A transformable wheel-legged robot has been designed with the applied chassis. As a variable topology mechanism, the robot has many changeable configurations. Finally the structure implementation of the robot was discussed.

Product design and development becomes increasingly knowledge-intensive and collaborative. It is very difficult to meet currently imperious needs for the traditional design mode, knowledge managing methods and the geometry-centric application tool. Designers require more generic knowledge of design and design process and more intelligent system. It establishes the FBPSS framework system supporting modeling of product function, behavior, principle, state and structure. Based on this FBPSS framework system, ontology-based product design system is developed through design knowledge repositories.

In this paper, we built a localized regression model to estimate the miles per gallon (MPG) characteristic for equipment engines based on a serious physical features of this engine. First, we statistically viewed these parameters to build up a basic understanding of the data we collected. Then, with the belief that engines with similar characteristics will perform similarly, we proposed a novel localized model with a novel optimal function based EM algorithm and a novel self-adjusted optimal clustering algorithm to estimate MPG based on the other fully studied engines with similar physical features.

This article constructed the stress distributions function expression of four free edges square basal bottom slab touching foundation respectively from the two aspects of symmetric and anti-symmetric load, placed the foundation on the surface of the sandy soil, do numerical simulation to the contact stress between foundation slab and foundation through the large scale finite element analysis software ANSYS, and fitting by adopting the contact stress function proposed in this article. The contact stress function and finite element numerical fitting result shows that the contact stress function proposed in this article can better reflect the actual contact stress distribution, also adapt to foundation slab with different width height ratio.

Took two layers of single span lateral sway semi-rigid connecting steel frame to bear vertical load function as the research object, adopting finite element method for solving the bucking load of the whole losing the stability of the semi-rigid connecting steel frame. Using based on the energy method and the three parabolic interpolation deflection curve function to obtain the relationship between the both element ends of internal force and displacement and introducing semi-rigid beam element stiffness matrix and geometric stiffness matrix of element integrate the global stiffness matrix which contains the flexibility of the connections and the component geometry nonlinear, thus deducing the stability characteristic equation of semi-rigid steel frame. And the MATLAB language composition program is applied to calculate the buckling load of overall losing stability of the semi-rigid steel frame, thus obtaining the buckling load of semi-rigid steel frame. The method is a very effective numerical calculating method which can solve the stability problems of relatively complicated stress conditions or relatively complicated structure composition conditions and it can also satisfy the requirement of higher calculation accuracy, easy for programming and calculation and of great practicability.

Carbon nanotubes/zirconia/hydroxyapatite biocomposites was prepared by hot-pressing sintering under Ar atmosphere. The influence of sintering temperature on the mechanical properties and microstructure of carbon nanotube/zirconia/hydroxyapatite biocomposites was studied. We tested the bending strength and fracture toughness by universal electronic materials testing machine. The component of the composites was tested by XRD. The fracture surface of the composites was observed by SEM. The results indicate that the bending strength and fracture toughness of the composites is lower when the sintering temperature is lower than 1200°C. The difference of bending strength and fracture toughness at 1200°C and 1300°C is little. The number of them has risen markedly than the low temperature which reached to189.2MPa and 1.8MPa·m-1/2 respectively. The composition of the composites is mainly of hydroxyapatite, zirconia, carbon nanotubes, and a small amount of calcium phosphate, which indicated that part of the hydroxyapatite has decomposed. SEM photographs show that the fracture surface of the composites sintered at 1200 °C and 1300 °C is ductile fracture status and has bigger density.

This paper demonstrated the importance of bolt tightening in engineering application, and given the injector clamp tightening of engine model. We given the calculation method of snug torque and angle of torque-angle tightening of bolt, and this calculation method of bolt tightening has an important control function. In addition, the torque and angle Adjustment method was given. We introduced the Experimental Study. Finally, the injector clamp tightening bolt M8×1 of JX4D30X engine as an example, Examples proved that the results of theoretical calculation and experimental study uniform. These studies have not been involved in other papers.

The petroleum ether-insoluble fraction of Dagang vacuum residue (DVR-PEIF) was subject to catalytic hydrogenation in the presence of Y zeolite. Most of compounds detected with GC/MS in the PE-soluble fraction of products from DVR-PEIF are saturated hydrocarbons, including chain alkanes and cyclanes. Small amounts of olefins and heteroatom-containing compounds (HOs) were also identified.

Curve fairing has an important influence on curve editing and geometric modeling. Though there has been several different kinds of fairing methods, Multiresolution curve fairing has higher efficiency and simpler algorithms. Different from existing multiresolution curve fairing, a new multiresolution approach is presented based on non-uniform semiorthogonal B-spline wavelets, which can be applied for NURBS curve fairing. It has no restriction to B-spline curves’ knot sequence. This method effectively overcomes the limit of uniform or quasi-uniform B-spline wavelets for fairing. A detailed example is given to show the effectiveness of this multiresolution fairing method.

The volume of workspace is one of the most important parameters to evaluate the flexibility of a robot. Monte Carlo Method and adaptive-divided mesh method were applied to analyze the workspace of the manipulator of a explosive-handling robot in mine. Firstly, the kinematical model of the manipulator was taken forward based on its main structure. Then, its kinematics analysis was given. Based on them, the manipulator’s workspace was analyzed by Monte Carlo Method and the cloud picture was completed. At last, the ‘Adaptive-divided Mesh Method’ was brought forward and the volume of the workspace was calculated with it. The result shows that the workspace’s volume is large enough and the working points in the workspace of the explosive-handling manipulator were distributed compactly and uniformly, which can satisfy the requirements with high efficiency.

There is no engineering experience for metro station construction by the PBA (Pile-Beam-Arch) method to enlarge an existing large-size shield tunnel in China. During enlarging construction by the PBA method, the spatial mechanical and deformational characteristics of metro station structure are still not clear. In this paper, the Gaojiayuan station is taken as an engineering background to study the spatial mechanical and deformational characteristics during enlarging construction by the PBA method. Based on soil-structure interaction theory, a three-dimensional finite element model is built to simulate the enlarging construction by the PBA method. The three-dimensional numerical results can be regarded as a valuable reference for enlarging construction by the PBA method in Beijing metro line 14.

In more and more complicated urban building environment, a new construction method that metro engineering is constructed by large-diameter shield and shallow mining method can be regarded as a great attempt in China. By taking the Gaojiayuan station of Beijing metro line 14 as an engineering background, the main construction steps for the platform of the metro station built by a large-size shield with an outer diameter of 10 m and the Pile-Beam-Arch (PBA) method are introduced. Based on the soil-structure interaction theory, a two-dimensional finite element model is used to simulate the shield tunneling and the platform construction by the PBA method to enlarge the shield tunnel. The ground deformation and structural stress of the platform are predicted. The numerical results can be regarded as a valuable reference for the application of the new construction method in Beijing metro line 14.

With the speedy development of Beijing mass transit, the land for metro engineering construction is becoming more and more insufficient; moreover, more and more complicated building environment problems are coming forth in future. In a complex building environment, how to choose available construction method to fast, safely and economically build metro engineering is worthy to be urgently studied in Beijing mass transit. Taking the experiment project of Beijing metro line No.14 as an engineering background, a new construction method that a running tunnel is firstly built by large-size shield method and then a metro station is constructed by shallow mining method to enlarge existing large-diameter shield tunnel is presented in this paper. Based on the building conditions of the experiment project, three architectural design schemes for the metro station and two kinds of construction plans are briefly introduced, and their advantages and disadvantages are analyzed as well. The new construction method can be used as a reference for the design and construction of metro engineering in China in the future.

A multiresolution approach is presented for NURBS curve fairing based on nonuniform semiorthogonal B-spline wavelets built. This method provides greater flexibility and applicability than uniform B-spline wavelets for multiresolution curve fairing. An example is presented to validate effectiveness of this multiresolution fairing method. Furthermore, the algorithm can be easily applied to NURBS curves in three dimensions as well as in two.