Journal ArticleDOI
Location-dependent queries in mobile contexts: distributed processing using mobile agents
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A system that supports distributed processing of continuous location-dependent queries in mobile environments and uses mobile agents to carry the processing tasks wherever they are needed.Abstract:
With the current advances of mobile computing technology, we are witnessing an explosion in the development of applications that provide mobile users with a wide range of services. In this paper, we present a system that supports distributed processing of continuous location-dependent queries in mobile environments. The system that we propose presents the following main advantages: 1) it is a general solution for the processing of location-dependent queries in scenarios where not only the users issuing queries, but also other interesting objects can move; 2) it performs an efficient processing of these queries in a continuous way; 3) it is especially well adapted to environments where location data are distributed in a network and processing tasks can be performed in parallel, allowing a high scalability; and 4) it optimizes wireless communications. We use mobile agents to carry the processing tasks wherever they are needed. Thus, agents are in charge of tracking the location of interesting moving objects and refreshing the answer to a query efficiently. We evaluate the usefulness of the presented proposal showing that the system achieves a good precision and scales up wellread more
Citations
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Journal ArticleDOI
Location-dependent query processing: Where we are and where we are heading
TL;DR: The technological context (mobile computing) and support middleware (such as moving object databases and data stream technology) are described, location-based services and location-dependent queries are defined and classified, and different query processing approaches are reviewed and compared.
Journal ArticleDOI
Non-Line-of-Sight Identification and Mitigation Using Received Signal Strength
TL;DR: This study addresses the NLOS identification and mitigation problems using multiple received signal strength (RSS) measurements from WiFi signals using several statistical features of the RSS time series, which are shown to be particularly effective.
Journal Article
MobiEyes: Distributed processing of continuously moving queries on moving objects in a mobile system
Bugra Gedik,Ling Liu +1 more
TL;DR: This paper introduces a set of optimization techniques, such as Lazy Query Propagation, Query Grouping, and Safe Periods, to constrict the amount of computations handled by the moving objects and to enhance the performance and system utilization of Mobieyes.
Proceedings ArticleDOI
Efficient Evaluation of Imprecise Location-Dependent Queries
Jinchuan Chen,Reynold Cheng +1 more
TL;DR: Three methods to improve the efficiency of queries that return probabilistic guarantees for location data with uncertainty are developed and Experimental simulation over a realistic dataset reveals that these approaches improve the query performance significantly.
Journal ArticleDOI
Using cooperative mobile agents to monitor distributed and dynamic environments
TL;DR: A decentralized, loose, and fault-tolerant monitoring approach based on the use of mobile agents is described, which has been successfully used in a real environment and experiments were carried out to prove its feasibility and benefits.
References
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Proceedings ArticleDOI
Models and issues in data stream systems
TL;DR: The need for and research issues arising from a new model of data processing, where data does not take the form of persistent relations, but rather arrives in multiple, continuous, rapid, time-varying data streams are motivated.
Proceedings ArticleDOI
Nearest neighbor queries
TL;DR: This paper presents an efficient branch-and-bound R-tree traversal algorithm to find the nearest neighbor object to a point, and then generalizes it to finding the k nearest neighbors.
Journal ArticleDOI
A foundation for representing and querying moving objects
Ralf Hartmut Güting,Michael H. Böhlen,Martin Erwig,Christian S. Jensen,Nikos A. Lorentzos,Markus Schneider,Michalis Vazirgiannis +6 more
TL;DR: The paper formally defines the types and operations, offers detailed insight into the considerations that went into the design, and exemplifies the use of the abstract data types using SQL.
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Natural language interfaces to databases-An introduction
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