Image encryption (IE) technology is vital to privacy, but the parameter range of the traditional image encryption technology is limited. So it is important to enhance the performance of IE methods. In this study, a plaintext associative IE based on the improved logistic map and hyperchaotic system is proposed. The improved logistic map scrambles the pixels of the image. Then the hyperchaotic system performs diffusion and confusion operations on the image. For parameters μ and r, the sequence generated by the improved logistic map can traverse and uniformly distribute in the space (0,1). The Lyapunov exponent of the improved logistic map is greater than 21.5. The correlation coefficients of the encrypted image pixels after encryption are all less than 0.05. The UACI and NPCR indices of the improved encryption method are close to their theoretical values of 98.6133 and 33.1287, respectively, which are higher than those of the reference methods. The improved encryption method overcomes the limitations in the parameter range of traditional image and text encryption techniques, slow encryption speed, and uneven chaotic sequences. This method has higher security and sensitivity, andit can be used to establish a plaintext associative IE method.

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This paper addresses the model consistency problem in the AUTOSAR modeling environment, aiming to achieve dynamic synchronization within or between different AUTOSAR modeling steps. Observing that the AUTOSAR component hierarchy can be very complex and the modification of one model can affect its consistency with the others, we propose to use a directed acyclic graph (DAG) with indexing mechanism to model the software component architecture. The idea is to assign each vertex as a modeling element and use a directed edge to represent an aggregation relationship between vertices. Then we present a set of consistency rules to ensure the model consistency. A prototype is developed and serves as a testbed for performance evaluation and illustrating the feasibility of our approach.