Abstract-With the advent of CMOS cameras, it is now possible to make compact, cheap and low-power image sensors capable of on-board image processing. These embedded vision sensors provide a rich new sensing modality enabling new classes of wireless sensor networking applications. In order to build these applications, system designers need to overcome challanges associated with limited bandwith, limited power, group coordination and fusing of multiple camera views with various other sensory inputs. Real-time properties must be upheld if multiple vision sensors are to process data, communicate with each other and make a group decision before the measured environmental feature changes. In this paper, we present FireFly Mosaic, a wireless sensor network image processing framework with operating system, networking and image processing primitives that assist in the development of FireFly Mosaic, we demonstrate an assisted living application capable of fusing multiple cameras with overlapping views to discover and monitor daily activities in a home. Using this application, we show how an integrated platform with support for time synchronization, a collision-free TDMA link layer, an underlying RTOS and an interface to an embedded vision sensor provides a stable framework for distributed real-time vision processing. To the best of our knowledge, this is the first wireless sensor networking system to integrate multiple coordinating cameras performing local processing.

Computer science is seeing a decline in enrollment at all levels of education. One key strategy for reversing this decline is to improve methods of student retention. This paper, based on a 10-month case study at the Department of Computer Science at the University of Illinois at UrbanaChampaign, examines two aspects of student retention at both the graduate and undergraduate levels: community identity and community relationships. Our data shows that students feel isolated from each other, faculty, and members of the greater computer science community. Given our findings, we highlight existing programs and propose new programs which improve student-community interactions. While the lessons learned might not apply at every institution, they constitute a valuable case study for improving conditions for students at large research universities.

Advances in wireless technology have brought us closer to extensive deployment of distributed real-time embedded systems connected through a wireless channel. The medium access control (MAC) layer protocol is critical in providing a real-time guarantee. We have devised a real-time wireless MAC protocol which, demonstrated in both simulations and implementation, provides better throughput than existing protocols and predictable temporal behavior with minimal impact on node failures, packet losses and noise in the channel.

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Large scale real-time systems consist of hundreds of commercial off-the-shelf (COTS) and custom software components. Mismatched assumptions between software components are a prime source of failures in these systems. Further, component assumptions are often implicit due to the limitations of current software interfaces. In this work, we introduce a framework to explicitly expose assumptions in software components, and automatically verify these assumptions during system integration. We manage the propagation and composition of these assumptions in the presence of changes and upgrades to individual components.