Steve D. Huseth

Localization in Wireless Sensor Networks

Within wireless sensor networks, the location of the sensor can be a critical attribute of the data sensed. A device knowing its relative position to the other devices in the wireless network or its absolute position with respect to a map increases the value of the data sensed. Sensing the precise location of wireless devices has been a topic of serious study for some time. A number of methods and techniques have been suggested, using various physical attributes (IR, acoustic, time of flight); however, we have chosen to emphasize received signal strength (RSS), which is simple to implement and uses the signal strength sampling capability used by the network layer of a wireless network. Using algorithms such as fingerprinting and multilateration, a reasonably accurate position estimate can be established depending on the density of the network devices and the environment in which they must operate. We discuss the previous work in RSS localization and describe the limitations of these algorithms from a practical and an experimental perspective. We will conclude with a discussion of our work using these algorithms in 3 wireless network test beds constructed in an industrial refinery and an office environment.

Framework Support For Knowledge-Based Software Development

The advent of personal engineering workstations has brought substantial information processing power to the individual programmer. Advanced tools and environment capabilities supporting the software lifecycle are just beginning to become generally available. However, many of these tools are addressing only part of the software development problem by focusing on rapid construction of self-contained programs by a small group of talented engineers. Additional capabilities are required to support the development of large programming systems where a high degree of coordination and communication is required among large numbers of software engineers, hardware engineers, and managers. A major player in realizing these capabilities is the framework supporting the software development environment. In this paper we discuss our research toward a Knowledge-Based Software Assistant (KBSA) framework. We propose the development of an advanced framework containing a distributed knowledge base that can support the data representation needs of tools, provide environmental support for the formalization and control of the software development process, and offer a highly interactive and consistent user interface.