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Radio Frequency Identification (RFID) is a kind of short-range radio technology for data acquisition and automatic identification. In large scale application of RFID system, RFID network planning (RNP) is one of the fundamental tasks need to be fulfilled. This paper proposed an efficient hybrid intelligent optimization approach for RNP. A RNP optimization model is designed in considering of coverage, cost, and the radiated power of readers. A hybrid intelligent optimization approach is proposed to optimize the model in a hierarchical fashion. Firstly, we used the intelligent optimization algorithm to regulate the number and position of the RFID readers for the coverage and cost objective. Then, the optimal radiate power of readers is computed by analytic calculation. Experimental results show that this hybrid intelligent optimization approach has the advantage in terms of the quality of RFID network deployment and computation efficiency comparing with the existing approaches.

In order to obtain overburden and surface deformation law, this paper takes S2S9 working face fully-mechanized mining of certain coal mine for example, uses the finite element ADINA software, and it establishes two-dimensional numerical model, analyzes overburden and surface deformation caused by the working face mining. The study shows the amount of each point movement in the top of the mined-out area gradually decreases from the bottom to up, and the range of surface movement is also increasing with advancement of the coal excavation. After the completion of the working face, it forms a subsidence curve which is symmetry for the maximum vertical point and an antisymmetric horizontal deformation curve. The zero point of horizontal movement is located above the center of mining sector, and the maximum tilt is 2.044mm·m.

Based on overburden of S2S9 working face fully-mechanized mining of certain coal mine, this paper uses the finite element ADINA software to analyze the vertical stress and shear stress of overburden under the condition of coal mining, especially the vertical stress decreasing and increasing zones, concentrated stress change and to discuss the distribution scope, peak value and spatial relation with the working face of Tre-suptorping stress. The study on the mine safe and efficient mining of other face has certain significance.

The interaction of a double-tube parallel tunnel excavation will have a larger additional shearing action on the adjacent pipelines. This paper, taking 202 Section of Line 2 on Dalian Metro as the background, uses the finite difference software to establish 3-D finite element analysismodel to simulate the double-tube parallel tunnel excavation. Deformation of adjacent pipelines is analyzed specially by numerical simulation of tunnel excavation and also the safety of the pipelines is forecasted. The conclusions and advices are important to design and guide the actual project construction safety.

The interaction of a double-tube parallel tunnel excavation will greatly influence on underground pipeline of its region. This paper, taking Dalian Spring Street subway station as the background, uses the finite difference software to establish 3-D finite element analysis model to simulate the effects of tunnel excavation on underground pipeline, in which different embedment, material properties and diameters are considered. By analyzing of the settlement and deformation law of pipeline, the least affected pipeline conditions are drawn to provide corresponding guidance for subsequent underground projects.

In the double-tube parallel tunnel excavation cross-range, it will result in a larger superimposed surface subsidence, and even induce land subsidence to cause the accident. This paper uses the finite difference FLAC3D software to have a numerical simulation on double-tube parallel tunnel excavation of Dalian Spring Street Station. The land subsidence law of a double-tube parallel tunnel excavation which is obtained by analyzing the vertical and longitudinal settlement curve can predictable similar ground subsidence caused by tunnel construction and guide the safety construction of practical engineering

To reduce the computational complexity of direction finding algorithms based on correlation processing, a fast algorithm is presented in this paper. Unlike the conventional direction finding algorithms which calculates the correlation coefficients in the whole azimuth range, the improved algorithm measure the direction of arrival (DOA) roughly first, then, measure the DOA only in finite angle interval and searches the maximal correlation coefficient, thus shorten the execution time greatly. In addition, the algorithm has no influence on the accuracy of direction finding. The best proportion between samples for rough measurement and samples for fine measurement is analyzed. Computer simulation results confirm that the proposed method can shorten the computation time greatly, and the proposed algorithm has practical application value in the instantaneous direction finding.

The joint has a significant effect on the dynamic characteristic of the mechanism, and the identification of the stiffness of the joints has become a key problem. In this paper, a method is presented for identifying the dynamic characteristic of joints. An experiment is designed to test the dynamic parameter of the bolted joints specimen; the identification method, based on experiment, has a high accuracy result. By taking a specimen to experiment and identify the dynamic characteristic of joints, the relationship between the preload on the bolts and the joints stiffness is acquired. In order to validate the accuracy of the result, the FEM software is used to simulate. There are only a small discrepancy between the results of identification and simulation.

The modal experiment of the three-section crossbeam was carried out by single-input multi-output method. Identify the stiffness and damping with single-degree-of-freedom identification method. Use ANSYS software APDL programming language and experimental data to establish the finite element model of joint surface of three-section crossbeam. Use modal analysis method analysis the three-section crossbeam which establishes FEM modeling of joint surface. The comparison of the analysis result and experimental result are shown. The FEM result of the three-section crossbeam established FEM modeling of joint surface is basically tally with the experimental result, the modeling methods for joint surface is feasible.

To verify the existing sports bicycle frames design and to achieve the fast and accurate self-design of frames, a simulation model of the frames is established during three development processes. First, the modal and static tests were designed for the study of a particular sports bicycle frame. Second, the initial simulation model of the frame was developed with Pro/Engineer and ANSYS Workbench software, and the simulation model was used to conduct the modal and static analysis on the frame. Finally, based on the comparison of the analysis and test result, the parameters of the simulation model were modified. The results show that the simulation model is consistent with the test result and it can be used for the optimal design of sports bicycle frame.

The combined three-section crossbeam is an important component in the heavy gantry CNC milling-lathing machine tool and the dynamic characteristics are key precision factors for the machine tool. Three sections of the combined crossbeam are bolted by large industrial bolts and the influence of bolted joints should be evaluated in the dynamic analysis of the combined crossbeam. The dynamic characteristics of the combined three-section crossbeam were extracted by the modal experiment. The FEM of the monolithic crossbeam was modeled to analyze the dynamic characteristic parameters. The comparison of the analysis result and experimental result were shown. The experimental result matched well with the FEM of the monolithic crossbeam without bolted joints. As a result, the influence of the bolted joints could be ignorable in dynamic characteristic for the combined three-section crossbeam.

Shield tunnel construction cause soil movement to harm the adjacent underground pipelines. This paper, taking Dalian Spring Street subway station as the background, uses the finite difference software to establish 3-D finite element analysis model to simulate the deformation of pipeline with 45* skew angle in the tunnel construction work. The results show: when the left tunnel push towards pipelines, due to the skew of the pipeline and tunnel, vertical displacement of pipelines is a certain shift to the left. When the right tunnel excavation is complete, the pipeline maximum settlement has a return to the center of the two tunnels. The settlement of pipeline is much bigger than horizontal displacement.