Both the deformation characters and the failure mode of the large cross-sectional longwall installation roadway under compound roof are becoming an emergent issue than ever before due to the rapid development of modern mining equipment. Various engineering applications have revealed that the insufficient design and inappropriate support technology are the main reasons for the fatal accidents as...

When the electromagnetic field in sapphire resonator corresponds to whispering gallery mode, it exhibits an extremely low dielectric loss. As result, oscillator has characteristics of ultra-low phase noise and high short-term frequency stability. The distribution is very important for realizing high-level oscillator. In this work, radial-axial mode matching method used theoretically analyze res...