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Increased traffic congestion makes intersection improvements are necessary to improve the capacity and traffic running conditions. Because of the influence of a certain intersection improvements is not limit to itself, but covers the intersections around it. The approach to find the boundary of signal group for traffic analysis due to a certain intersection improvements is discussed in this paper. Firstly, two kinds of correlation degree are modeled, which are the basis of intersection grouping. Saturation degree and free flow travel time are considered in the model of correlation degree between two adjacent intersections considers, while correlation degree between any two intersections in the network is analyzed using Laplacian matrix algorithm. Secondly, the approach to find intersection group boundary is proposed. Thirdly, two measures are adopted in quantifying the results of intersection grouping: minimum average cut correlation degree and minimum traffic influence on the intersections outside of boundary. At last, the developed method is used on a city road network. The results of case study confirm the validity of the proposed approach.

To meet the demand of the innovative teaching research in machinery or relevant major, a connecting rod teaching machine based on metamorphic mechanisms was put forward, which was suitable for the teaching and experiment simultaneously, improving the teaching effectiveness. The metamorphic mechanism was proposed as the kernel of whole design, integrating multiple evolution of linkage. The virtual prototype technology is applied to create model. The dynamic simulation of topological change in the process was carried out to verify the feasibility of mechanism motion, and two solutions to reduce impact were put forward. The screw transmission telescoping mechanism was designed. Parameter simulative analysis of the model by ADAMS verified the rationality of the design, combining with mechanical analysis.

Four types of curing agents were added into the soil at different ratios. Then the treated soil samples were molded. The compressive strengths of the soil samples were determined at different curing ages. The samples were detected by the X-ray diffraction (XRD) and thermogravimetry / differential thermal analysis (TGDTA). The results indicated that the curing agents A and C used in the experiment had a significant improving effect on the strength of the soil.

This paper introduces analysis the development process of CAD technology, application of the AutoCAD software in engineering field and teaching as well as the significance of the development of two times the. This paper analyzes in detail the development of common language, and the use of Visual BASIC development and application of software based on AutoCAD. The author elaborates the software interface design and method calls AutoCAD in VB. Finally, the design and implementation of a programming language re-development system based on AutoCAD is concerned. The test results show that the developed AutoCAD two development system has good practical value.

A nonlinear model of bolt joints structure in vibration environment is built and Structure Intensity(SI) of it is calculated by FEM as an approach for the state identification of bolts joints structure in vibration environment. The plots of the structure intensity vector under different preforce were obtained and showed the SI changes of bolt joints structure with different preforces.and showed the energy distribution and transmission are different preforces

Few studies have adequately focused on passenger route choice behavior with congestion consideration, or provided useful guidance on passenger route choice and hence the transit assignment model, which is the writing motivation of this paper. With congestion consideration, travel cost is assessed and and ways to reduce it also identified. Finally, an actual transit network of Chengdu is used as a case study to demonstrate the benefits of the proposed model. The result indicates that the vehicle capacity is an important factor that cant be ignored and a better understanding of passenger route behavior could significantly benefit public transit system.

A fast sparse representation face recognition algorithm based on Gabor dictionary and SL0 norm is proposed in this paper. The Gabor filters, which could effectively extract local directional features of the image at multiple scales, are less sensitive to variations of illumination, expression and camouflage. SL0 algorithm, with the advantages of calculation speed，require fewer measurement values by continuously differentiable function approximation L0 norm and reconstructed sparse signal by minimizing the approximate L0 norm. The algorithm obtain the local feature face by extracting the Gabor face feature, reduce the dimensions by principal component analysis, fast sparse classify by the SL0 norm. Under camouflage condition, The algorithm block the Gabor facial feature and improve the speed of formation of the Gabor dictionary. The experimental results on AR face database show that the proposed algorithm can improve recognition speed and recognition rate to some extent and can generalize well to the face recognition, even with a few training image per class.

Light propagation in the air is easily affected by the environment. Shaft bending vibration and torsional vibration are needed to be measured at the same time. The different vibration state are coupled each other. For these reasons, it is necessary to design the optical fiber laser Doppler measurement system and develop the integrated optical fiber system, which is in favor of various vibration modes decoupling and can improve the signal-to-noise ratio. The double parallel beam differential scheme is adopted in the torsional vibration measurement, which the light exposed in the air is coupled into the optical fiber. The optical fiber heterodyne Doppler interference measuring method is adopted in the bending vibration measurement. The laser Doppler vibration measurement technology is applied to a rotating shaft vibration measurement. Comprehensive measuring technology is developed, which can simultaneously measure bending vibration, torsional vibration and the rotation speed of shaft.

Combined with the collected mining conditions and geological characteristics of coal mine mined-out areas, this paper analysed the present collapse situation of the coal mine mined-out area, the mechanism and influence of the surrounding environment. It puts forward the comprehensive analysis model considering multiple factors. And corresponding conclusions could provide theoretical guidance for urban planning, construction and sustainable development research.

By research of the mix technology of VC++ and Matlab based on Matcom software, the insufficiencies of data processing in VC++ and visual programming in Matlab have been sloved effectively in signal processing. The own definition functions by matlab can be converted to the C code with Matcom,then the functions can be called anywhere if you need.Using this mix technology, the vibration signals collected by UA307 data acquisition card have been transformed by FFT and the results are consistent with Matlab’s. The mixed-program can operate independently without Matlab software and this method is a good reference to the development of the signal processing system.

This paper aims at research on fundamental principles of long concrete wall cracks in basement on the basis of series basic experiments and engineering practices. Relying on typical project, we use ABAQUS finite element analysis software to conduct simulation analysis to provide evidence for integrated control of cracks. Simulation analysis results show that the reinforcement stresses has tight connections with constraint mode of structure, for instance, column side and the location connected with foundation; effective limits of boundary constraints to structure deformation and constraints of free-form deformation on long wall structure make the concentration of reinforcement stresses nearing constraint location relatively obvious; under the effects of temperature and contraction, internal force of concrete wall will be re-distributed, therefore, reinforcement stress of concrete can not directly reveal actual force distribution inside the wall, but the overall trend is close to concentrated pattern of reinforcement stress.

Based on the vibration mechanics theory and system’s state equation, the state-space model of the flange bolted-joints structure is established. According to the dynamic characteristics of bolted connection, the parameters of the state-space model, such as rigidity and damping, can be identified. The accuracy of simulation model is validated, by comparing the simulation analysis results with the vibration test results, and an efficient method of recognition or fault diagnosis of bolted joints in vibratory environment is proposed.

In this paper, discrete wavelet transform (DWT) is used to analyze the acceleration signals near to the loose bolt, in order to study the characteristics of bolted joint condition. Firstly, an experimental system is built based on the NI data acquisition equipment. Secondly, based on qualitative analysis of the loose process of the bolted joints and spectrum analysis of response signals, an appropriate wavelet function is chosen and decomposed levels are determined. Lastly, according to the amplitude of each level, the contour diagrams are drawn and the Root Mean Square (RMS) of detailed coefficients at the sensitive level is calculated. Experimental result shows that both DWT contour diagrams and RMS at sensitive level have significant difference when preload changes.

The three-dimensional vibratory strengthening and polishing technology was used to strengthen and polish aeroengine blades with complicated surfaces. At first, the principle of the strengthening and polishing process was introduced, which combined strengthening process with polishing process. Then, the technological parameters influenced on the surface quality were investigated. The principal variables were the media hardness, the frequency and amplitude of the vibration, and duration of the vibratory strengthening and polishing. The optimum parameters were obtained. Experimental results revealed that, after strengthening and polishing, the surface roughness of aeroengine blades was reduced from Ra0.35-0.5μm to Ra0.1-0.12μm, and fatigue strength was increased by approximately 50%.

According to Mianyang’s 11th five-year planning outline, Xianhai Lake (the national –level water conservancy scenic spot )should take full advantage of geography and ecology edge to promote Mianyang prosperity and exalt its image while making Xianhai Lake a national –level eco-tourism economic region which will serve as a place for leisure, vacation, fitness exercise, convention and exhibition and so on. Chenxiang Village is next to Xianhai Lake and it’s a significant part of Xianhai Lake tourism outline. Thus this article deals with Chenxiang Village architecture and environmental landscape planning .

Based on the group theory and the complex division method, the dimension classified method for planar multi-loop mechanism was analyzed. Firstly, the dimension classified inequation was derived from the singularity of constraint equation of the mechanism. Subsequently, by using the classified inequation, the complex division method of the structure-parameter-space was explored. By using the mechanism symmetry group, the simplification method of the division results was analyzed. Finally, by using an example, the classified methods were validated. The results show that all information about mechanism classification are included in the division results. Besides, this method is appropriate for complicated mechanism classification by computer.

The structural intensity of shells structure was analyzed based on finite element method (FEM) in this paper. The expressions of structural intensity of plate in FEM were given under harmonic excitation. By using coordinate transformation, mathematical expressions of the structural intensity of shells structure in FEM were deduced. The structural intensities of a rectangular plate and combined structure of tube and plate were calculated. The vector plots of structural intensity under different excitation frequencies were analyzed. The results show that the structural intensity under different frequencies are different, the vector plots present directly the distribution and propagation of energy in shells structure.