974543
A framework for sensor management in wireless and heterogeneous sensor network
This paper proposes a framework for sensor configuration and management in wireless multi sensor network system, which is responsible for taking decisions in order to coordinate the assignment and scheduling of sensors best suited for the application. A sensor manager operates over a heterogeneous sensor network, which provides sensory data from multiple types of sensors. The application of this work is tracking the movement of objects in a moderately occupied confined space. Simulations were run to study the operations of the proposed sensor manage in such application. The simulation results are compared to other published results to show the effectiveness of this work.
1548147
Level-of-detail based modeling of object movement in tracking and surveillance system
This paper proposes a level-of-detail (LOD) based method for modeling object movement in wireless sensor network tracking and surveillance applications. This method addresses the dilemma of achieving maximum information with limited power and bandwidth in wireless sensor network. LOD provides the researchers with various fidelity levels of data to perform such tasks as regional traffic statistics analysis, object classification and clustering, and at the highest level, object behavior analysis. A simulation test bed extracted from the sensor network hardware platform is being built to allow users to easily generate objects with various behavioral models, design three-dimensional sensor deployment layouts and related surveillance environments, test the accuracy and efficiency of tracking, and calculate lifetime of system and power consumption. An illustrative experiment with preliminary results is provided at the end of this paper.
3410538
A Flexible Context-Aware Authorization Framework for Mediation Systems
Security is a critical concern for mediator-based data integration among heterogeneous data sources. This paper provides a modeling and architectural solution to the problem of mediation security that addresses the security challenges including context-awareness, semantic heterogeneity, and multiple security policy specification. A generic, extensible modeling method for the security policies in mediation systems is presented. A series of authorization constraints are identified based on the relationship on the different security components in the mediation systems. Moreover, we enforce the flexible access control to mediation systems while providing uniform access for heterogeneous data sources.
2104066
Design and evaluation of a resource selection framework for Grid applications
While distributed, heterogeneous collections of computers ("Grids") can in principle be used as a computing platform, in practice the problems of first discovering and then organizing resources to meet application requirements are difficult. We present a general-purpose resource selection framework that addresses these problems by defining a resource selection service for locating Grid resources that match application requirements. At the heart of this framework is a simple, but powerful, declarative language based on a technique called set matching, which extends the Condor matchmaking framework to support both single-resource and multiple-resource selection. This framework also provides an open interface for loading application-specific mapping modules to personalize the resource selector. We present results obtained when this framework is applied in the context of a computational astrophysics application, Cactus. These results demonstrate the effectiveness of our technique.
2764337
Automated compile-time and run-time techniques to increase usable memory in MMU-less embedded systems
Random access memory (RAM) is tightly-constrained in many embedded systems. This is especially true for the least expensive, lowest-power embedded systems, such as sensor network nodes and portable consumer electronics. The most widely-used sensor network nodes have only 4-10 KB of RAM and do not contain memory management units (MMUs). It is very difficult to implement increasingly complex applications under such tight memory constraints. Nonetheless, price and power consumption constraints make it unlikely that increases in RAM in these systems will keep pace with the requirements of applications.We propose the use of automated compile-time and run-time techniques to increase the amount of usable memory in MMU-less embedded systems. The proposed techniques do not increase hardware cost, and are designed to require few or no changes to existing applications. We have developed a fast compression algorithm well suited to this application, as well as run-time library routines and compiler transformations to control and optimize the automatic migration of application data between compressed and uncompressed memory regions. These techniques were experimentally evaluated on Crossbow TelosB sensor network nodes running a number of data collection and signal processing applications. The results indicate that available memory can be increased by up to 50% with less than 10% performance degradation for most benchmarks.
37078966
Entity-Based Noun Phrase Coreference Resolution
In this paper we propose an NP coreference resolution system which does resolution on the entity-level. The framework of the system is presented and different resolution strategies are investigated.
8275741
Efficient relational joins with arithmetic constraints on multiple attributes
We introduce and study a new class of queries that we refer to as ACMA (arithmetic constraints on multiple attributes) queries. Such combinatorial queries require the simultaneous satisfaction of arithmetic constraints on three or more attributes from different relations, and thus often involve expensive multi-join operations. Building on techniques from constraint programming, we develop preprocessing methods, algorithms, and a new constrained join operator that allow ACMA queries to be evaluated efficiently within a conventional relational database engine. We present the results of a careful performance evaluation of both our new approach and the conventional nested-loop join algorithm. Measurements of tuples read, intermediate tuples generated, and execution time shows that our approach achieves superior performance for ACMA joins.