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1

Development of mathematical model for cyclic behaviour of blind bolted HSS column components

Wang Z. Y., Yang X., Wang Q. Y., Liu Y.

Archives of Civil and Mechanical Engineering

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2017

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Vol. 17, no. 4

943--953

EN

This paper presents an experimental and finite element analysis based mathematical modelling of cyclic behaviour of the component of hollow structural section (HSS) columns under bolt tensile loads. This component acts as an important constituent part to the blind bolted connections with HSS columns. Two typical failure modes and their related hysteretic curves are examined experimentally. It is shown that force versus displacement curves under monotonic loading can be regarded as the upper bound of the envelope of the counterpart cyclic response. Moreover, the hysteretic force–displacement curves of test columns with relatively thick tube walls demonstrate significant pinching manner thus less energy dissipative capacity. Based on the calibrated finite element model, the flexibility of tube wall and its influences on the connection response are compared for two failure modes. Parametric analyses are also performed to investigate the influence of geometric parameters on the elastic stiffness and yield strength. The mathematical hysteretic models allowing for the behaviour of the connections in two typical failure modes are proposed that distinguishes the developed model from those reported in the literature. It is demonstrated that the proposed model incorporating degradations of stiffness and/or energy dissipation can achieve a good representation of test hysteretic behaviours.

2

Tracking technology for optoelectronic imaging platform of tethered balloon based on DGPS/INS

Wang Y. W., Wang Z. Y., Zhou W. H., Han X. Q.

Opto-Electronics Review

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2011

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Vol. 19, No. 2

242-248

EN

In this paper, a tracking method for optoelectronic imaging platform of tethered balloon based on difference global positioning system/inertial navigation system is presented in detail. The location and attitude information of optoelectronic imaging platform, the azimuth and elevation angles of camera’s line of sight are used by this method to locate the ground target at the centre point of the camera's field of view through corresponding coordinate transformation. And then, the method makes use of the update position and attitude information to solve the theoretical point of camera's line of sight inversely. Finally, an angle control commend will be sent to the inertially-stabilized turntable on the optoelectronic imaging platform, which will adjust its azimuth and elevation angle to make the camera's line of sight to the ground target. A lot of experiments are conducted, and the results show that the initial ground target is always in the centre of camera's field of view no matter how the balloon's position and attitude change, and the new location data of ground target has little difference with the initial location data, while the difference between them is close to 0.

3

Rotor power loss in a PM SM by calculation, simulation and measurements, mutual verification of methods

Vannier J. C., Kaczmarek R., Wang Z. Y., Randria A.

Electrical Power Quality and Utilisation. Journal

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2006

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Vol. 12, nr 2

113-116

EN

The subject of the paper is the comparison of four complementary methods of the rotor loss estimation in a PM SM, supplied by a PWM voltage source. An ANSYS based finite element model produces values of W, the magnetic energy stored, and P, the rotor losses. On analytical level the machine is represented by a parallel two elements equivalent circuit for each voltage harmonic. Its parameters are estimated using P and W values. Finally, the eddy current losses representation in the ANSYS code is verified for magnets under study by direct losses measurements. The calculation results are compared with some measured values resulting from analysis and harmonic decomposition of the machine total losses.