Context awareness

About: Context awareness is a research topic. Over the lifetime, 5790 publications have been published within this topic receiving 119944 citations.

Reducing feature models to improve runtime adaptivity on resource limited devices

Abstract: Mobile devices like smartphones are getting increasingly important in our daily lifes. They are used in various environments and have to dynamically adapt themselves accordingly in order to provide an optimal runtime behavior. Naturally, adapting to continuously changing environmental conditions is a challenging task because mobile devices are always limited in their resources and have to adapt in real-time. In this paper, we introduce an approach that enables resource limited devices to adapt to changing conditions using dynamic software product lines techniques. Therefore, feature models are reduced to a specific hardware context before installing the adaptive mobile application on the device. This reduces the amount of possible configurations that are compatible with the device and, thereby, minimizes the costs and the duration of an adaptation during runtime.

Electric and Plug-in Hybrid Vehicle Networks: Optimization and Control

Abstract: This book explores the behavior of networks of electric and hybrid vehicles. The topics that are covered include: energy management issues for aggregates of plug-in vehicles; the design of sharing systems to support electro-mobility; context awareness in the operation of electric and hybrid vehicles, and the role that this plays in a Smart City context; and tools to test and design massively large-scale networks of such vehicles. The book also introduces new and interesting control problems that are becoming prevalent in the EV-PHEV's context, as well as identifying some open questions. A particular focus of the book is on the opportunities afforded by networked actuation possibilities in electric and hybrid vehicles, and the role that such actuation may play in air-quality and emissions management.

A Framework for Decentralized, Context-Aware Mobile Applications Using Semantic Web Technology

Abstract: The recent evolution in mobile devices, combined with rapid advancements in identification techniques, has lead to new opportunities for mobile application developers: mobile applications that can be made aware of their environment and the objects in it. Additionally, by combining mobile devices and identification technology with the Web, mobile applications can be developed that exploit services and information associated with nearby objects. In this paper, we present an application framework that supports the development of such mobile applications, without having to rely on a central service to provide information on the user's environment. Furthermore, by deploying Semantic Web technology, the integration of information from various information sources is facilitated, allowing for expressive and powerful personalized information delivery.

Context Awareness Group Buying in D2D Networks: A Coalition Formation Game-Theoretic Approach

Abstract: In this paper, we proposed a context-aware group buying mechanism to reduce users’ data cost based on the content similarity. Each user's cost is formulated as the combination of the content-aware data cost and location-aware sharing cost. Data cost is the payoff of the spectrum owner's channel to download files and sharing cost is the energy and time cost in transmitting files among the coalition. Compared with downloading data alone, users would like to form different groups and download the traffic data first and then share data among the group to achieve a lower cost. The cost reducing problem through group buying mechanism is modeled as a coalition formation game (CFG). Besides the traditional Pareto order, a coalition order maximizing the coalition's benefit and a selfish order maximizing users’ benefit are proposed. The CFGs with the two proposed orders are proved to be potential games, respectively, and the existence of the stable coalition partitions are also guaranteed by Nash equilibria. A cooperative exchange mechanism is designed, where users can make decisions cooperatively to achieve better performance. Simulation results show that the context awareness group buying reduces the cost and improves the benefit significantly compared with the situation without context awareness. The proposed orders both have better performance than the Pareto order.