Learn More
We present TinyOS, a flexible, application-specific operating system for sensor networks, which form a core component of ambient intelligence systems. Sensor networks consist of (potentially) thousands of tiny, low-power nodes, each of which execute concurrent, reactive programs that must operate with severe memory and power constraints. The sensor network(More)
— We investigate the custody transfer mechanism proposed for enhancing reliability in delay-tolerant networks. This mechanism, which utilizes hop-by-hop transfer of reliable delivery responsibility, shares many features in common with a database transaction. By considering custody transfer in this light, we observe that it can cause the creation of(More)
Citation Thiagarajan, Arvind et al. " VTrack: accurate, energy-aware road traffic delay estimation using mobile phones. The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Abstract Traffic delays and congestion are a major source of inefficiency , wasted fuel, and commuter frustration.(More)
Wireless sensor networks are an emerging area of research interest with a number of compelling potential applications. By architecting sensor networks as virtual databases, we can provide a well-understood non-procedural programming interface suitable to data management, allowing the community to realize sensornet applications rapidly. We argue here that in(More)
We present the Tiny AGgregation (TAG) service for ag-gregation in low-power, distributed, wireless environments. TAG allows users to express simple, declarative queries and have them distributed and executed efficiently in networks of low-power, wireless sensors. We discuss various generic properties of aggregates, and show how those properties affect the(More)
  • Daniel J Abadi, Mitch Cherniack, Nga Tran, Adam Batkin, Tien Hoang, Stan Zdonik +55 others
  • 2008
There are two obvious ways to map a two-dimension relational database table onto a one-dimensional storage interface: store the table row-by-row, or store the table column-by-column. Historically, database system implementations and research have focused on the row-by row data layout, since it performs best on the most common application for database(More)
  • Joshua Harlan Lifton, Thesis Reader, Samuel Madden, To Brian, Deb, Peggy Mike +36 others
  • 2007
The commoditization of low-power radios, a rich set of sensors, longer-lasting batteries, and feature-rich microcontrollers has prompted significant research efforts to imbue physical environments with the responsiveness and awareness afforded by ubiquitous, unobtrusive, low-maintenance sensor networks. However, despite these technical advances, there has(More)
Visualizations are frequently used as a means to understand trends and gather insights from datasets, but often take a long time to generate. In this paper, we focus on the problem of rapidly generating approximate visualizations while preserving crucial visual properties of interest to analysts. Our primary focus will be on sampling algorithms that(More)
— In this paper, we propose a new benchmark for scientific data management systems called SS-DB. This benchmark , loosely modeled on an astronomy workload, is intended to simulate applications that manipulate array-oriented data through relatively sophisticated user-defined functions. SS-DB is representative of the processing performed in a number of(More)
  • Vladimir Bychkovsky, Bret Hull, Allen Miu, Hari Balakrishnan, Samuel Madden
  • 2006
The impressive penetration of 802.11-based wireless networks in many metropolitan areas around the world offers, for the first time, the opportunity of a " grassroots " wireless Internet service provided by users who " open up " their 802.11 (Wi-Fi) access points in a controlled manner to mobile clients. While there are many business, legal, and policy(More)