Energy-efficient, On-demand Reprogramming of Large-scale Sensor Networks

As sensor networks operate over long periods of deployment in difficult to reach places, their requirements may change or new code may need to be uploaded to them. The current state of the art protocols (Deluge and MNP) for network reprogramming perform the code dissemination in a multi-hop manner using a three way handshake whereby meta-data is exchanged prior to code exchange to suppress redundant transmissions. The code image is also pipelined through the network at the granularity of pages. In this paper we propose a protocol called Freshet for optimizing the energy for code upload and speeding up the dissemination if multiple sources of code are available. The energy optimization is achieved by equipping each node with limited non-local topology information, which it uses to determine the time when it can go to sleep since code is not being distributed in its vicinity. The protocol to handle multiple sources provides a loose coupling of nodes to a source and disseminates code in waves each originating at a source, with mechanism to handle collisions when the waves meet. The protocol’s performance with respect to reliability, delay, and energy consumed, is demonstrated through analysis, simulation, and implementation on the Berkeley mote platform

COIN: Opening the internet of things to people's mobile devices

People's interaction with IoT devices such as proximity beacons, body-worn sensors, and controllable light bulbs is often mediated through personal mobile devices. Current approaches usually make applications operate in separate silos, as the functionality of IoT devices is fixed by vendors and typically accessed only through low-level proprietary APIs. This limits the flexibility in designing applications and requires intense wireless interactions, which may impact energy consumption. COIN is a system architecture that breaks this separation by allowing developers to flexibly run a slice of a mobile app's logic onto IoT devices. Mobile apps can dynamically deploy arbitrary tasks implemented as loosely coupled components. The underlying runtime support takes care of the coordination across tasks and of their real-time scheduling. Our prototype indicates that COIN both enables increased flexibility and improves energy efficiency at the IoT device, compared to traditional architectures

Team-level programming of drone sensor networks

Autonomous drones are a powerful new breed of mobile sensing platform that can greatly extend the capabilities of traditional sensing systems. Unfortunately, it is still non-trivial to coordinate multiple drones to perform a task collaboratively. We present a novel programming model called team-level programming that can express collaborative sensing tasks without exposing the complexity of managing multiple drones, such as concurrent programming, parallel execution, scaling, and failure recovering. We create the Voltron programming system to explore the concept of team-level programming in active sensing applications. Voltron offers programming constructs to create the illusion of a simple sequential execution model while still maximizing opportunities to dynamically re-task the drones as needed. We implement Voltron by targeting a popular aerial drone platform, and evaluate the resulting system using a combination of real deployments, user studies, and emulation. Our results indicate that Voltron enables simpler code and produces marginal overhead in terms of CPU, memory, and network utilization. In addition, it greatly facilitates implementing correct and complete collaborative drone applications, compared to existing drone programming systems

Economic and Security Challenges Faced by Smart Grid

openIn this dissertation I have mentioned the components of the smart grid and how it uses computer technology to improve the communication, automation, and connectivity of the various components of the power network. The main aim of protecting the grid from any hacks and fraud are cyber security since we are dealing with two ways communication flow of electricity and information technology. Advantages and disadvantages of smart grid implementation that affect the economy .Ultimately renewable resources are used for energy compensation and the real time monitoring is used for accurate and reliable consumption since the demand is increasing globally, and improves consumption management

Excellentia Eminentia Effectio

"In these pages you will learn about the fascinating research endeavors that each of our faculty members is undertaking. We have divided their research into the broad categories of health, sustainability, information, and systems. While we recognize the imperfect nature of categorizing research that, by its very nature may be interdisciplinary or transdisciplinary, we nonetheless believe it will be helpful as a way to see the depth and breadth of our research endeavors within each grouping. As you read the profiles on these pages, I know you will begin to appreciate that, taken as a whole, the research spectrum at Columbia Engineering is exceptional and that, as our professors go about their work, they are at the cusp of making breakthroughs that will have a major impact on the way we live our lives today and tomorrow.