Sensor systems for positioning and identification in ubiquitous computing

Technologies for position sensing and identification are important to have in ubiquitous computing environments. These technologies can be used to track users, devices, and artefacts in the physical milieu, for example, locating the position of a cellular phone in av physical environment. The aim of this thesis was to survey and classify available technologies for location sensing and identification. We have made a literature study on both commercial and research-oriented systems and technologies for use in indoor and outdoor environments. We compared the characteristics of the underlying sensing technologies with respect to physical size, sensing method, cost, and accuracy. We conclude the thesis with a set of recommendations to developers and discuss the requirements on future sensing technologies and their use in mobile devices and environments

Sensor systems for positioning and identification in ubiquitous computing

Technologies for position sensing and identification are important to have in ubiquitous computing environments. These technologies can be used to track users, devices, and artefacts in the physical milieu, for example, locating the position of a cellular phone in av physical environment. The aim of this thesis was to survey and classify available technologies for location sensing and identification. We have made a literature study on both commercial and research-oriented systems and technologies for use in indoor and outdoor environments. We compared the characteristics of the underlying sensing technologies with respect to physical size, sensing method, cost, and accuracy. We conclude the thesis with a set of recommendations to developers and discuss the requirements on future sensing technologies and their use in mobile devices and environments

Nonlinear Contingency Screening for Voltage Collapse

A method for estimating the severity of generator unit outage and multi-terminal branch outage contingencies with respect to voltage collapse in large-scale electric power systems which includes the steps of estimating a post-contingency saddle-node bifurcation induced voltage collapse point of an electric power system following a set of generator unit outages and/or a set of branch outages and calculating a distance to collapse of said power system. The post-contingency voltage collapse point is determined by application of a nonlinear contingency screening method.Sponsorship: Illinois Institute of TechnologyUnited States Paten

Component-based Approach for Embedded Software Development

Abstract The rapid growth in the demand of embedded systems and the increased complexity of embedded software pose an urgent need for advanced embedded software development techniques. Software technology is shifting toward semi-automated code generation and integration of systems from components. Component-based development (CBD) techniques can significantly reduce the time and cost for developing software systems. However, there are some difficult problems with the CBD approach. Component identification and retrieval as well as component composition require extensive knowledge of the components. Designers need to go through a steep learning curve in order to effectively compose a system out of available components. In this paper, we discuss an integrated mechanism for component-based development of embedded software. We develop an On-line Repository for Embedded Software (ORES) to facilitate component management and retrieval. ORES uses an ontologybased approach to facilitate repository browsing and effective search. Based on ORES, we develop the code template approach to facilitate semi-automated component composition. A code template can be instantiated by different sets of components and, thus, offers more flexibility and configurability and better reuse. Another important aspect in embedded software is the nonfunctional requirements and properties. In ORES, we capture nonfunctional properties of components and provide facilities for the analysis of overall system properties