Optical Fiber Sensing Based on Reflection Laser Spectroscopy

An overview on high-resolution and fast interrogation of optical-fiber sensors relying on laser reflection spectroscopy is given. Fiber Bragg-gratings (FBGs) and FBG resonators built in fibers of different types are used for strain, temperature and acceleration measurements using heterodyne-detection and optical frequency-locking techniques. Silica fiber-ring cavities are used for chemical sensing based on evanescent-wave spectroscopy. Various arrangements for signal recovery and noise reduction, as an extension of most typical spectroscopic techniques, are illustrated and results on detection performances are presented.

Unrecognized Exodus, Unaccepted Accountability : The Looming Shortage of Principals and Vice Principals in Ontario Public School Boards (Working Paper 24)

To the apparent surprise of policy makers at the provincial and school board levels, Ontario’s public schools are about to experience a massive exodus of principals and vice principals. This report, funded by a grant from the Ontario Principals’ Council, details the scale of the retirement wave currently hitting Ontario’s public school boards. Data collected from 946 practicing school administrators suggest that the retirement rates will be almost 20 per cent higher than provincial estimates. Anecdotal evidence suggests that the pool of qualified candidates for these positions is also shrinking. Already, fewer individuals are applying for each available vacancy. The study examines the major dissatisfiers in the current role of school principal as experienced by incumbents. Interviews were also conducted with 92 individuals identified as exceptional candidates for the principalship who had opted not to follow that career path in order to determine what factors they found most important in their decision making. The report concludes with recommendations for the province, school boards and principals' organizations.