| Real-time systems differ from non-real-time systems in many significant aspects such as timliness, predictability, reliability, durability, etc. With the development of distributed real-time system, new problems such as real-time communication, heterogeneity are introduced in real-time systems. Real-time systems nowadays tend to be more and more complex and large in scale, and at the same time are required to be more flexible, autonomous, reliable and adaptive. Traditional design and developing methods of real-time system are close and appropriative, and seldom take into account the adaptability to environment. Thus they can't satisfy the requirements of modem complex distributed real-time applications. This dissertation organically integrates Object-Oriented technology, middleware technology and QoS technology into the design and development of distributed real-time applications, making it less complex, and the systems can be more adaptive to changing environment.Non-functional requirements to real-time systems such as timliness, reliability, security and throughput can be classified to QoS requirements of application layer which are put forward by real-time application, and the service provider is a development and execution platform for real-time applications. What is the relationship among QoS requirements of application layer and network layer, operating system layer, and middleware layer? Can the design and development of real-time system be simplified by using low-layer QoS mechanisms? These are the focuses of this dissertation.As an object-oriented middleware, CORBA has been successfully applied into non-real-time area, and effectively reduced the developing cost and maintenance cost of large-scale non-real-time applications. Applying CORBA to real-time computing area naturally attracts many researchers and practicers.This dissertation focuses on using QoS technology and CORBA technology into the design and development of distributed real-time applications. First, this dissertation researches the QoS framework, outlining the scope of content of this dissertation; Second, it researches multi-dimension QoS(MQoS) technology and universal layered model for MQoS in depth; Then it designs and realizes an MQoS framework on real-time CORBA; Finally, it illustrates the application of the MQoS framework on real-time CORBA to satellite control system. The main research contents include: Systematically researches the complete structure of QoS framework and its fivedeciding principia, which prove that QoS technology is very suitable for thecharacters of distributed real-time applications such as timeliness, complexity,distributing and adaptability. Analyses the reasons of the advent of multi-dimension QoS for the first time Analyses the relationship between multi-dimension QoS and multi-dimensior resources, based on which gives the method to implement multi-dimension QoS management under different situations. Compared with the method currently usec by many researchers both at home and abroad, which is to generally resolve the multi-dimension QoS and multi-dimension resources problem through the optimization of configuration under multiple constraints, the method presented ir this dissertation is more concrete and easier to carry out. Proposes a universal layered model for MQoS, which uses MQoS middleware tc fill up the QoS gap between network/OS layer and application layer. This mode is composed of a low-layer MQoS middleware, which shields different networl and OS to upper layer, a high-layer MQoS middleware(i.e. middleware orienting a kind of applications), which shields system-layer QoS parameters and provide! specialized QoS understood by this kind of applications. Based on the current QoS research in CORBA, this dissertation researches QoS management in CORBA via another approach: integration. That is, to construe the QoS structure as an organic whole by integrating all the QoS and real-tim< application related mechanisms in each layer of real-time CORBA with the universal MQ...
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