Bulletin Editorial Oct 2017

Editorial, Issue: September 2017

Radiotherapy Current Awareness Bulletin January 2017

To quantify the performance of the Clarity ultrasound (US) imaging system (Elekta AB, Stockholm, Sweden) for real-time dynamic multileaf collimator (MLC) tracking. The Clarity calibration and quality assurance phantom was mounted on a motion platform moving with a periodic sine wave trajectory. The detected position of a 30 mm hypoechogenic sphere within the phantom was continuously reported vi...

Yan - Bin Jia Oct 17 , 2017

in x and y. The degree of the curve is the degree of the polynomial f(x, y). A parametric curve α(t) = (p(t), q(t)), where p(t) and q(t) are polynomials in t, is an algebraic curve. This is because we can eliminate t from the two polynomial equations x = p(t) and y = q(t) using the resultant technique, and obtain a polynomial equation, called their resultant, in x and y. The resultant has a deg...

Yan - Bin Jia Oct 3 , 2017

We want to find a measure of how ‘curved’ a curve is. Since this ‘curvature’ should depend only on the ‘shape’ of the curve, it should not be changed when the curve is reparametrized. Further, the measure of curvature should agree with our intuition in simple special cases. Straight lines themselves have zero curvature. Large circles should have smaller curvature than small circles which bend m...

Editorial Jan-Mar 2017.cdr