Princeton University

Professor Andrew Appel received $500,000 from the National Science Foundation for a collaborative project to develop techniques that verify the safety, security and dependability of large-scale software systems. Current methods for software verification are divided into two classes: "lightweight approaches" that are scalable to large systems, but less effective for low-level components; and "foundational approaches" that use logic to prove individual program correctness effectively, but have not been successfully scaled up. In collaboration with researchers at Harvard University and Yale University, Appel intends to combine these two methodologies with the goal of dramatically improving the reliability and security of large-scale software systems, many of which are critical to the world's infrastructure.

Professor Robert Calderbank was awarded $160,000 from the National Science Foundation to develop a new theory for active sensing -- a technology used for real-time monitoring of vast amounts of data collected by sensors. By employing a novel combination of signal transmission techniques, Calderbank and his collaborators seek to design a framework enabling improved performance and reliability of surveillance applications, including systems used for drug traffic detection, defense radar and weather-monitoring. Calderbank is joined in the effort by collaborators from Colorado State University and Purdue University.

Senior research scientist Christiane Fellbaum was granted $357,000 from the National Science Foundation to perform an extensive technical overhaul of WordNet, a large electronic database of English words that provides definitions and links words together based on their meanings. The freely available system, developed at Princeton and accessed tens of thousands of times every day, is a cornerstone for research in computer science and information processing, but its potential is constrained by its current design. Fellbaum's proposed enhancements will improve significantly WordNet's ability to discriminate word sense -- for instance, recognizing whether the word "check" is being used in the context of banking, restaurants, textile patterns or the game of chess. The new system architecture also will incorporate crucial capabilities that extend the system's applicability to technical domains, such as biology and medicine.

Assistant professor Michael Freedman and Professor Jennifer Rexford were awarded $750,000 from the National Science Foundation to develop a system architecture that dramatically improves the Internet's ability to serve as a hosting platform for networked services, including content distribution networks, virtual worlds and online gaming. The Internet was primarily designed to support communication between pairs of host machines at fixed locations, meaning that today's networked services are difficult to design and manage. Freedman and Rexford propose a clean-slate architecture called SCAFFOLD (Service-Centric Architecture For Flexible Object Localization and Distribution) that will lower the barrier to building and deploying networked services that are scalable, reliable, secure, energy-efficient and easy to manage.

Freedman and Rexford also have received a $606,000 subaward from a National Science Foundation grant to BBN Technologies to support their work on SCAFFOLD and to use the platform to build and deploy distributed services on the Global Environment for Network Innovations (GENI) project -- a virtual laboratory that allows researchers to explore and test future internets. Additionally, they will use SCAFFOLD to test several underlying GENI technologies and demonstrate their facility for supporting new network architectures. The researchers, along with Professor Larry Peterson, also received a subaward of $300,000 from a National Science Foundation grant to BBN Technologies to support a campus trial of Enterprise GENI.

In addition, Freedman was granted $340,000 from the National Science Foundation to revisualize the Internet ecosystem to one that would provide more affordable and ready access to digital content. Recognizing that the majority of Web traffic is due to distribution of content, Freedman will collaborate with scholars from Stanford University and Texas A&M University to investigate how network and system architecture can be designed to enhance content distribution for three key constituencies: users, content providers and network providers. The project will address how to improve the interaction of current networks as well as how to design "content aware" networks for the future.

Professor Niraj Jha was awarded $500,000 from the National Science Foundation to develop approaches that address software security breaches on often-attacked embedded systems, such as wireless handsets, personal data assistants and networked sensors. Security techniques developed for computer systems cannot usually be applied to these devices, given their limited processing capabilities and battery energy constraints. Jha and his colleagues will leverage their previous work on malicious code detection and prevention in computer systems to develop new methodologies that significantly improve the accuracy and efficiency of attack detection in embedded systems.

Professor Antoine Kahn has received a subaward of $621,000 from a Department of Energy grant to the University of Arizona to improve the performance of organic photovoltaic devices, which use carbon-based molecules to harness energy from the sun. Kahn and his colleagues will focus on how chemical doping, or the incorporation of certain molecules, of the organic molecular films used in organic solar cells can be used to improve the power conversion efficiency of the devices, which could greatly enhance their use in practical applications.

Associate professor Vivek Pai will lead a $500,000 effort to improve Web access in disadvantaged regions. While much research focuses on improving content distribution by Internet servers, little attention has been paid to the development of client-side solutions to enhance Web access. Pai and his colleagues will explore the development of "content retrieval networks" that use network models intelligently and predictively to request content and maximize Web access performance. This could yield tremendous benefits in information access for rural areas of the United States, poor urban neighborhoods with limited broadband access, many K-12 schools and other regions with low network capacity. The grant for this project comes from the National Science Foundation.

Professor Larry Peterson has received a $250,000 subaward from a National Science Foundation grant to BBN Technologies to integrate PlanetLab -- an open platform for developing, deploying and accessing planetary-scale Internet services -- and related testbeds around the world into an international federated research facility. Understanding the mechanisms that enable successful federation and the policy issues that arise in the process will help inform the development and deployment of future real-world internets.

Senior research scholar Loren Pfeiffer has received a subaward of $45,000 from a National Science Foundation grant to Case Western Reserve University to continue his work on the electrical transport properties of gallium arsenide semiconductors. In previous work, Pfeiffer produced a material demonstrating the highest electron mobility ever reported for a semiconductor.

Dean of the School of Engineering and Applied Science H. Vincent Poor has received a $175,000 grant from the National Science Foundation to support a collaborative research effort on efficient and secure wireless communication. The project will investigate the use of cooperative beamforming as a low-cost alternative to directional antennas for wireless networks, enabling high throughput and power-efficient communications. The interdisciplinary effort -- combining concepts in signal processing, decision theory, optimization, information theory, communications, networking and economics -- is intended to provide a blueprint toward building new perspectives on future wireless network design.

Professor James Sturm has received a $25,000 subaward from a Department of Energy grant to Phycal, a company focused on developing algae-derived fuel sources, to design a microfluidic devise that separates algae from their watery environments. Water must be removed from the plants -- a process known as dewatering -- before their naturally occurring oils can be extracted for use as algal biofuels, which may confer advantages over other potential biofuels, including a much higher oil yield per acre of harvested crop. The device being developed by Sturm and his collaborators uses microscopic posts arranged in carefully designed patterns to sort algae and water as they move over the device at high flow rates by steering particles of different sizes to follow different paths.

Professor Sigurd Wagner has received a subaward of $30,000 from a National Science Foundation grant to Solarity, a developer of photovoltaic cells, to support research on the use of amorphous silicon films as absorbers in solar cells. Wagner and his collaborators will use a technique known as plasma-enhanced chemical vapor deposition to make amorphous silicon on templates patterned at sub-micrometer dimensions to enable their use in solar cell devices.