Stephen Dawson-Haggerty

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We present A-MAC, a receiver-initiated link layer for low-power wireless networks that supports several services under a unified architecture, and does so more efficiently and scalably than prior approaches. A-MAC's versatility stems from layering unicast, broadcast, wakeup, pollcast, and discovery above a single, flexible synchronization primitive. A-MAC's(More)
We present the architecture, design, and preliminary evaluation of ACme, a wireless sensor and actuator network for monitoring AC energy usage and controlling AC devices in a large and diverse building environment. The ACme system consists of three tiers: the ACme node which provides a metering and control interface to a single outlet, a network fabric(More)
An emerging class of sensor networks focuses on reliable collection of high-resolution signals from across the network. In these applications, the system is capable of acquiring more data than can be delivered to the base station, due to severe limits on radio bandwidth and energy. Moreover, these systems are unable to take advantage of conventional(More)
For nearly a decade, wireless sensor network research and development largely assumed that the Internet architecture was ill suited for sensor network applications. Many in the field argued that Internet protocols were impractical for the resource constrained devices that were being embedded in the physical world; that the end-to-end architecture was(More)
Commercial buildings are attractive targets for introducing innovative cyber-physical control systems, because they are already highly instrumented distributed systems which consume large quantities of energy. However, they are not currently programmable in a meaningful sense because each building is constructed with vertically integrated , closed(More)
We report on an experimental case study of personalized lighting controls built on top of an infrastructure designed to enable rapid development of applications in commercial buildings. Our personalized lighting controls (PLC) use an existing standard commercial building lighting automation system and require no new hardware to deploy. PLC presents(More)
As more and more <i>physical information</i> becomes available, a critical problem is enabling the simple and efficient exchange of this data. We present our design for a simple RESTful web service called the Simple Measuring and Actuation Profile (sMAP) which allows instruments and other producers of physical information to directly publish their data. In(More)
We report on investigations, conducted at the 2006 Johns Hopkins Workshop, into the use of articulatory features (AFs) for observation and pronunciation models in speech recognition. In the area of observation modeling, we use the outputs of AF classifiers both directly, in an extension of hybrid HMM/neural network models, and as part of the observation(More)
We present insights obtained from conducting a year-long, 455 meter deployment of wireless plug-load electric meters in a large commercial building. We develop a stratified sampling methodology for surveying the energy use of Miscellaneous Electric Loads (MELs) in commercial buildings, and apply it to our study building. Over the deployment period, we(More)
Buildings account for a large portion of the world's total delivered energy consumption. With smartphones becoming increasingly ubiquitous and sensor networks growing more mature, buildings can provide personalized and context-aware services to an occupant while minimizing energy consumption. This paper proposes the architecture of a Human-Building-Computer(More)