we may wish to provide the blind with artificial eyes that enable them to see ? and this is not just a silly, unrealizable pipe dream 我们可以希望为盲人提供假眼使他们重见光明?这并非愚蠢的,无法实现的幻想。
this method overcomes the difficult and unrealizable experiment conditions that are used to measure the absolute attenuation coefficient and impels the technique of ultrasonic characterization to be more closed to the engineering requirements and more practical 该方法克服了绝对衰减系数测定法对实验条件要求极为苛刻、难以实现的不足,使得超声表征技术更接近工程条件、更具实用价值。