Large track maintenance machine is one of the most important components of modernization of rail technical equipment. The sleeper supporting stiffness after large track maintenance operation has an effect on the safety and stability of train operation. This article make some conclusions through the analysis the influence of large track maintenance machine operation on sleeper supporting stiffness. It is indicated that during the maintenance operation, ballast compactness is enhanced and the supporting stiffness increases by tamping operation, but the supporting stiffness decreases due to the effect of stabilizing machine. After ballast cleaning operation, the supporting stiffness decreases to 10% of the original state, but back to 70%~110% of the original state after stabilizing operation. The influence of supporting stiffness on safety and stability of train operation should be taken into consideration in determining the allowable running speed after cleaning operation.

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MIMO radar system that transmits orthogonal waveforms is an emerging technology that has significant application potential. Compared to traditional phased-array radar, orthogonal transform waveform can bring many advantages. In this paper, we present a novel binary phase code sequence suitable for orthogonal design. This phase code sequence is computationally efficient compared to other algorithms previously proposed in the literature. We provide some numerical examples to demonstrate the performances of the coded pulse signal.

ABSTRACT:Microwave portion of the electromagnetic spectrum are effective for observations of vegetation not only to leaf but also woody parts of vegetation. Specifically, microwave emissivity varies strongly with surface roughness, polarization, look-angle and water content. Microwave Vegetation Index (MVI) is one of the microwave indexes that are based on zero-order model. The zero order models applicable when the scattering contribution with in the vegetation is negligible. In this paper MVI in different frequencies (Base on WCOM project) and different angles (Base on SMOS data) are calculated by Matrix Doubling model to take in to account multiscattering effects within the vegetation. Then because MVI is depends on vegetation information we tried to analysis its behaviour in different densities of corn canopy by comparing to vegetation optical depth. The result shows linear relationship with height correlation between MVI and effective optical depth. So it can be a useful index in vegetation study for future satellite mission as WCOM.