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Cyber-Physical Systems (CPS) is a hot research topic in recent years. CPS described by highly integrated via a communication network between the calculation unit and the physical object is a class of complex systems. A wide range of application prospects in CPS, represents the direction of the development of a new generation of industrial technology, and attaches great importance to all walks of life. Meanwhile, CPS involves multiple disciplines such as computer science, communication and control science, system theory, design methods, design tools, and many other aspects of the challenges currently facing. The time characteristic is a key factor of the real-time system, the reliability and quality of the system largely depends on the real-time nature. Time characteristics, however, scattered in the various features of the whole system, the aforementioned code confusion and disperse code, system code is not easy to read, easy to modify, easy to produce inconsistent, reusability and difficult to modify and upgrade a series of questions . Therefore, the time characteristics alone as one aspect of the aspect-oriented modeling has become an ideal method. Aspect-oriented technology as a new technology based on the separation of concerns in the field of software development has been given the application has a large number of relatively mature aspect-oriented programming language aspects of programming in some common technical framework to get better reflected. But still do not have a unified aspect-oriented modeling, modeling standards or universal. The most widely used UML standard so far there is no support for aspect-oriented or aspect-oriented modeling through UML extension mechanism. For the time characteristics of the real-time system modeling, has been a lot of research. Combined with formal description AOSDM-UML model to real-time extensions, the time separating the constructor for a time, to establish a more complete model to model the system time, is a better approach. This article focused on the subject of CPS, introduced the basic concepts and characteristics, and pointed out that its current challenges facing. To discuss the new demands of the CPS time semantics, and describes some of the research directions. The combined the UML MARTE framework for time modeling aspect-oriented extension of UML, and combined MARTE framework, based timing model based on UML. The real-time characteristics of the CPS, decomposition, and for different aspects of the establishment of a time corresponding to characteristic model. Time characteristics of the first division of the basic time, time events, timing mechanisms, time services in four areas. Every aspect can be extended UML modeling. Secondly, CPS has a discrete-time, continuous time, the characteristics of the mixing time, the time characteristics is divided into discrete-time, continuous time, mixing time, and establish a corresponding model. Again, the time characteristics are divided into deterministic time limit, the randomness of the time limit, the ambiguity of the time limit of three aspects, and establish a corresponding model. The aspect-oriented modeling, using different methods for different time characteristics then through oriented method of weaving mechanisms to these models needed to integrate. Later in this article on the worst-case execution time analysis, and proposed species-level time synchronization algorithm to achieve clock synchronization
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