Research On Terminals Techniques Of Pervasive Computing

Over time, the evolution of computing has decreased the tight coupling between the user and his or her computing resource and environment. The computing is more flexible in resource usage and freedom from collocation. Pervasive computing will be the following computing mode. In pervasive computing, the terminal will be anywhere and people can access and manipulate information anywhere at anytime using it. Currently, there have been many kinds of terminals. But these terminals just have some simple capabilities of pervasive computing, and cannot satisfy the requirements of pervasive computing. Based on the resource management, the dissertation is devoted to show the research on the theory and technology of pervasive computing terminals.The power consumption is important which should be considered in pervasive computing terminals. The efficient consumption of power is discussed in details, which includes two parts: the harmonization of power requirement of system and application with the state of battery; the longer run times of battery based on the structure of power management which can consume power efficiently. The power modes and management strategy fitting with the pervasive computing terminals are also presented.The pervasive computing environments are inherently turbulent; the resources available to terminals change dramatically and unpredictably over time. Therefore, the terminals should be adaptive in response to the changing environment. With adaptation, terminals can provide high quality services when resources are enough and degraded services when resources are poverty. The adaptive architecture AAAS is proposed, based on application-aware adaptation mode and control theory. AAAS is flexible. The adaptive part is independent on specific OS, and has the capability to support extended resource types. Furthermore, AAAS is fair, stable and agile in global resource utilization. These properties are not present in other adaptive systems for pervasive computing terminals currently.illDuring the application development process of pervasive computing terminals, the methods are very important in software quality, cost and development cycle. The application design method PCTD of pervasive computing terminals is proposed and analyzed in depth. PCTD includes OOFD and MFDT. OOFD is an object-oriented software development process of terminals which developing software through a consistent combination of UML, MSC and SDL to support an iterative process that covers all aspects of system development. OOFD uses the information hiding technology, and can suit for tasking structure. MFDT is a multi-fidelity design technology of terminal application, which uses fuzzy control model in nonlinear adaptive decision. According to the present states of resources, MFDT relaxes the requirement of single output specifications, which allows a range of possible outcomes to suit for the adaptive application.A prototype of pervasive computing terminals called pPT is described at the end. The software architecture of pPT is BSoPT which providing high degree of openness, modularity, scalability, security, network connectivity, low power consumption and adaptation. pPT can satisfy the requirements of typical application in eBusiness, and has been applied successfully in WEB phones. At present, pPT is also being used in the development of some mobile terminals, such as smart phones, PDAs, and so on.