Research And Application Of Software Adaptive Mechanism Under Pervasive Computing

With the rapid development and mutual integration of technology in the field ofwireless communication, distributed computing and human-computer interaction, ubiquitouscomputing has been integrated into all aspects of people’s life. In ubiquitous computingenvironment, the number of users and their locations are constantly changing, the systemrequires computing devices and software systems to dynamically adapt to changes of thesurrounding environment, and tries to not disturb the user’s normal use. Therefore, thesoftware adaptive ability brings new demands and challenges in ubiquitous computing.Self-adaptability is an ideal goal of software applications and many scholars havedeeply investigated from different point of view and background. However, in ubiquitouscomputing, software always presents a set of new characteristics, such as the initiative oftheir behaviors, the heterogeneity of their constituents and the openness of theirenvironments. Therefore, the existing research works still having some limitations. First, theexisting software construction method can’t be used in ubiquitous computing. In ubiquitouscomputing, the dynamic software environment may exceed the expectations of thedevelopment phase, which requires the software infrastructure framework of the systemcan’t bind to the specific scenarios, and can flexibly adjust the software online adaptiveability. Second, the reusability of existing adaptive mechanism can’t meet the needs ofubiquitous computing. With the complexity of software constantly increasing, how toimprove the reusability of software adaptive mechanism, reduce the development cost andimprove the development efficiency, has become a hot topic.To solve above problems, a new conceptual model for adaptive software named ASCMis designed to guide the paper. The model reconciles both individual and collectiveadaptability and allows a third-party to guide the self-adaptive process at runtime. Then,under the guidance of this model, we research two aspects for self-adaptive software,including the approach to construct self-adaptive software individuals and how to improvethe reusability of adaptive software mechanism under the ubiquitous computing. Thecontent of this paper can be generalized as follows:(1) For defects of traditional conceptual model about adaptive software, a newconceptual model named ASCM for ubiquitous computing is designed. On this basis, wepresent a detail description of how to construct ubiquitous-computing oriented self-adaptive software, namely we propose an engineering approach for the construction of self-adaptivesoftware base on a compound control process, which is made up of three parts: the ASCMcomponent model, the ASCM unit structure framework, online adjustment. With thisapproach, we can build the self-adaptive software in the ubiquitous computing, which hasthe advantage of sensitivity on environment and architecture, and its adaptability can beadjusted with fine-grained at runtime.(2) To settle the low reusability of traditional adaptive software mechanism, we presenta fine-grained adaptive mechanism solution from the strategic level. Based on the existingcoarse-grained strategy adjustment (insert, delete, replace components, etc), a newstrategy-based adaptive mechanisms to support fine-grained adaptive adjustment is designed,including function components’ fine-grained adjustment and strategy-based adaptivemechanism’ fine-grained adjustment.(3) Finally, an ASCM-based management system using Java technology is developed,which supports fine-grained adaptive adjustment. The management system verifies thefeasibility and effectiveness about the previous work. The results of performance evaluationshow that its performance has been significantly better than the initial system.