Xem 1-3 trên 3 kết quả Ultrasonic phased
  • The idea of using ultrasonic waves in medical and engineering fields came from military applications of sound waves in sonar systems. Sokolov, Firestone, Simons, and several other researchers are among the ones who studied this high frequency kind of wave in the first half of twentieth century. Ultrasonic waves are defined as those with frequencies higher than 20 kHz. The constant development of data acquisition systems and probes seems to work, removing the upper limit of the wave frequency that can be acquired.

    pdf304p qsczaxewd 25-09-2012 34 9   Download

  • The quality of phased array and synthetic aperture ultrasonic images is limited by several factors determined by the sound propagation physics and diffraction laws. Image quality is mainly determined by: Resolution, which depends on signal bandwidth (in the axial direction) and on the aperture extent (in the lateral direction); Dynamic range, which is bounded by the ratio of the main to the sidelobes level and is related to the smallest features detection capability.

    pdf25p thaodien102 06-11-2015 8 2   Download

  • In the implementation of our strategy we focus on the following ESG factors: Environmental: For us this means that we focus on climate change. We believe that climate change issues are very important and that climate change (related) policy will lead to more focus on, for instance, energy efficiency and urban regeneration and that it will lead to shifting tenant and investor preferences; Social: For us this means that we focus on human rights and work conditions.

    pdf22p quaivatxanh 01-12-2012 18 4   Download

Đồng bộ tài khoản