船舶制冷系统对改善船员和旅客的生活和工作条件、降低能耗和物耗、提高船舶营运效率有着重要意义，因此提高船员制冷系统维修水平是......

This thesis proposes a new air-filled parallel plates modified lens antenna based on the Luneburg lens theory to meet th......

The effectiveness of a fluid-loaded sandwiched viscoelastic layer in suppressing acoustic scat-tering and radiation has ......