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The bridge pavement subjected to vehicle loads is the most vulnerable component in the highway bridge and overloaded vehicles can result in serious damage to the bridge pavement more easily. Therefore, it is necessary to consider the pavement in vehicle-bridge interaction (VBI) system. However, the bridge pavement is not considered in the traditional VBI system or the viscoelasticity of bridge pavement is ignored. In this study, a new vehicle-pavement-bridge interaction (VPBI) system is established. The viscoelastic asphalt pavement is simulated with the continuously and uniformly distributed spring-damper. The equivalent stiffness coefficient and equivalent damping coefficient of the pavement are determined through dynamic mechanical analysis (DMA) test and finite element method. The equations of motion for VPBI system can be derived using Lagrange equation and the modal superposition method. Then the crucial parameters such as displacement at mid-span of bridge, acceleration of vehicle body, tire contact force, and pavement deformation are obtained. The effects of vehicle velocity, bridge span, tire contact area, pavement stiffness coefficient, and pavement damping coefficient on VPBI responses are analyzed. The results show that (1) The pavement is compressive during vehicle passing bridge and its dynamic deformation fluctuates around initially static deformation of pavement. (2) Increasing the stiffness of pavement can rapidly reduce the deformation of pavement, while the pavement damping has the opposite effect. (3) The increase of bridge span can conduct exponentially growth of dynamic responses of VPBI system. The pavement deformation will increase by 7.9% if the bridge span is lengthened by 5 m. This study provides a reliability response analysis method for VPBI system. [ABSTRACT FROM AUTHOR]

Considering the nonlinear property of suspension damping and tire stiffness, a full-vehicle model is built for a heavy-duty truck. A modified preview driver model with nonlinear time delay is inserted into the vehicle model to compute the suitable steering angle of the front wheel and to make the vehicle follow the required route. Next, the finite element model of a five-span continuous curved highway bridge is established, and the bridge’s inherent frequencies and modes are obtained. The curved bridge and the vehicle are coupled by three-directional tire forces, and a three-directional driver–vehicle–bridge interaction model is presented. The presented vehicle model and bridge model are verified by comparing with the published works. The dynamic impact factors of vertical, lateral, and torsional displacements of the bridge are calculated when a vehicle is traversing through the bridge, and the impact factors’ distributions along the bridge are analyzed. The effects of vehicle driving conditions on impact factors are also researched. It is found that the impact factor calculated from the present specification for a straight bridge is smaller than that from the three-directional driver–vehicle–bridge interaction model, and the vertical and torsional impact effects at the third span midpoint are greater than the lateral impact effect. [ABSTRACT FROM AUTHOR]

Tringa totanus is declining throughout Europe and performing protection in China. In this study, we sequenced the complete mitochondrial genome using PCR method. It is the first published complete mitochondrial genome of T. tetanus, which is a circular molecule of 16,818 bp, and it contains 13 typical vertebrate protein-coding genes, 22 tRNA, and two rRNA. The phylogenetic tree was constructed to validate the taxonomic status of T. totanus, exhibiting it a closer relationship to T. glareola. [ABSTRACT FROM AUTHOR]

In this paper, the power spectrum resolution problem of dual-frequency coherent mixing signals is analyzed when the Doppler frequency difference is small. The power spectrum function formula of the four optical coherent mixing signals is obtained using statistical theory and the Wiener–Khinchin theorem. The influence of delay time and light source line width on the power spectrum of dual-frequency coherent signals is analyzed using this formula. The results show that delay time only affects the peak of the power spectrum of the coherent signal. An increase in the line width of the light source broadens the signal power spectrum and reduces the peak value. The necessary condition for distinguishing the Doppler frequency difference is that the theoretical Doppler frequency difference is greater than 1/5 times the line width of the light source. [ABSTRACT FROM AUTHOR]

Tringa totanus is declining throughout Europe and performing protection in China. In this study, we sequenced the complete mitochondrial genome using PCR method. It is the first published complete mitochondrial genome of T. tetanus , which is a circular molecule of 16,818 bp, and it contains 13 typical vertebrate protein-coding genes, 22 tRNA, and two rRNA. The phylogenetic tree was constructed to validate the taxonomic status of T. totanus , exhibiting it a closer relationship to T. glareola ., Competing Interests: No potential conflict of interest was reported by the authors., (© 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)