We describe a new approach to power saving and battery life extension on an untethered laptop through wireless remote processing of power-costly tasks. We ran a series of experiments comparing the power consumption of processes run locally with that of the same processes run remotely. We examined the trade-off between communication power expenditures and the power cost of local processing. This paper describes our methodology and results of our experiments. We suggest ways to further improve this approach, and outline a software design to support remote process execution.

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This research proposes and tests an approach to engineering distributed file systems that are aimed at wide-scale, Internet-based use. The premise is that replication is essential to deliver performance and availability, yet the traditional conservative replica consistency algorithms do not scale to this environment. Our Ficus replicated file system uses a single-copy availability, optimistic update policy with reconciliation algorithms that reliably detect concurrent updates and automatically restore the consistency of directory replicas. The system uses the peer-to-peer model in which all machines are architectural equals but still permits configuration in a client-server arrangement where appropriate. Ficus has been used for six years at several geographically scattered installations. This paper details and evaluates the use of optimistic replica consistency, automatic update conflict detection and repair, the peer-to-peer (as opposed to client-server) interaction model, and the stackable file system architecture in the design and construction of Ficus. The paper concludes with a number of lessons learned from the experience of designing, building, measuring, and living with an optimistically replicated file system. * For example, Ficus uses an 'update notification' daemon (a push) to tell other replicas asynchronously of a new file version. This typically results in a much faster propagation than relying on periodic volume-wide file reconciliation (pulls).

- ?One approach to detecting insider misbehavior is to monitor system call activity and watch for danger signs or unusual behavior. We describe an experimental system designed to test this approach. We tested the system's ability to detect common insider misbehavior by examining file system and process-related system calls. Our results show that this approach can detect many such activities. *

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This paper presents a thorough evaluation of CS for Scientists, a CS 1 course designed to provide future scientists with an overview of the discipline. The course takes a breadth-first approach that leverages its students' interest and experience in science, mathematics, and engineering. In contrast to many other styles of CS 1, this course does not presume that its students will study more computer science, but it does seek to prepare them should they choose to. We summarize the past year's worth of assessments of student learning, retention, and affect -with particular attention paid to women's voices. Where possible, we contrast these student measures with those from a traditional, imperative-first CS1 that this new course replaced. The data thus far suggest that CS for Scientists significantly improves students' understanding of CS, its applications, and practice.

This paper describes an introductory CS course designed to provide future scientists with a one-semester overview of the discipline. The course takes a breadth-first approach that leverages its students' interest and experience in science, mathematics, and engineering. In contrast to many other styles of CS 1, this course does not presume that its students will study more computer science, but it does seek to prepare them should they choose to do so. In addition to describing the curriculum and resources, we summarize our preliminary assessments of this course and a comparison with the more traditional, imperative-first introduction it replaced. The data thus far suggest that this CS for Scientists course improves our students' understanding of CS, its applications, and practice.