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SUMMARY Changes in environmental forces provide an opportunity for audit firms to move away from an up front and reactive audit planning approach to one that is more agile. Agility involves quicker adaption to the external and internal environments and can result in improved operating performance, quality, and client satisfaction. One way to introduce agility in a project-based organization is to adopt Scrum, an agile project management approach that has been applied in other industries to allow organizational teams to review, reflect, learn, and adapt. This “inspect-and-adapt” philosophy inherent in Scrum enables teams to effectively work in ever-changing conditions, resulting in a high level of sustainable productivity. We provide an overview of key Scrum principles and concepts and address future areas for Scrum research.

As part of a free-space optical communications experiment over a 5km horizontal path, an extensive database of tilt-stabilized receiver data was collected for C 2 n conditions ranging from benign to very strong. This paper focuses on the scintillation measurements made during those tests. Ensemble probability distributions are compiled from these results, and are subsequently compared with standard channel models such as the log-normal and gammagamma distributions. Statistical representations of temporal behavior are also developed from this database. Accurate statistical models of atmospheric channel effects have proved to be invaluable in the development of high-performance free-space transceivers.

MIT Lincoln Laboratory designed and built two free-space laser communications terminals, and successfully demonstrated error-free communication between two ground sites separated by 5.4 km in September, 2008. The primary goal of this work was to emulate a low elevation angle air-to-ground link capable of supporting standard OTU1 (2.667 Gb/s) data formatting with standard client interfaces. Mitigation of turbulence-induced scintillation effects was accomplished through the use of multiple small-aperture receivers and novel encoding and interleaver hardware. Data from both the field and laboratory experiments were used to assess link performance as a function of system parameters such as transmitted power, degree of spatial diversity, and interleaver span, with and without forward error correction.

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