Focusing on the issue that Advanced Audio Coding (AAC) is being transmitted unsafely and the steganalysis scheme's development has fallen behind relatively, a universal steganalysis scheme of AAC compressed domain was proposed. Based on the embedding influence caused by several known AAC Modefied Discrete Cosine Transform (MDCT) stegonagraphy methods, several steganalysis sub-featrues were constructed from multi-order differential correlations of AAC's inter-frame and intra-frame MDCT coefficients, then the sub-features were fused by different weights according to AAC's own coding principle, and the random forest classifier was used to distinguish embedded audio and normal audio. The experimental results show that the proposed steganalysis scheme has good performance in general detection compared to the existing algorithm; especially, the detecting rate of each stegonagraphy method is higher than 80% when the realative embedding rate is 50%.

To make the ordering model more fit to the actual operation of the supply chain, the collaborative ordering models of multi-echelon inventory system based on the hybrid demand were constructed. These models assumed that only the demand of the most downstream node in the supply chain was independent demand, and the demand of all the other upstream nodes were related demand. And the related demand was a massive demand, so its inventory cost structure was different from the one of the independent demand. Therefore, after analyzing the cost structure of the multi-echelon inventory system with hybrid demand, the collaborative ordering models allowing or not allowing out of stock of determined demand system were given. In addition, the collaborative ordering model of the uncertain demand system was also constructed based on the safety stock analysis. Then the genetic algorithms of these models were given. And, the simulation shows that they are good ways to get satisfying order policy.