in this paper, we make use of the properties of the umbilic to research circle section question of quadric in 3-dimensional euclidean space. we give the equations of these circle sections.
文章利用脐点的性质研究了二次曲面的圆截口问题,并给出了与二次曲面交线为圆的圆截口的方程的一种求法。
method the ratio of systolic and diastolic blood stream(s/d value)of umbilic artery was detected by color doppler ultrasound detector.
方法应用彩色超声多普勒仪器进行胎儿脐动脉血流检测,并分析胎儿及分娩前后情况与血流检测的关系。
in this paper, we make use of the properties of the umbilic to research circle section question of quadric in 3-dimensional euclidean space.
文章利用脐点的性质研究了二次曲面的圆截口问题,并给出了与二次曲面交线为圆的圆截口的方程的一种求法。