This paper introduces a simple index that helps to assess the degree of aging or rejuvenation of repairable systems. The index ranges from -1 to 1. It is negative for the point processes with decreasing ROCOF and is positive for the point processes with increasing ROCOF. Index Terms aging, rejuvenation, homogeneity, non-homogeneity. ACRONYMS CDF cumulative distribution function CIF cumulative i...

BACKGROUND The treatment of breast cancer involves a multidisciplinary approach in which radiotherapy plays a key role. AIM The conformity index and the homogeneity index are two analysis tools of a treatment plan using conformal radiotherapy. The purpose of this article is an analysis of these two parameters in the assessment of the treatment plans in 58 patients undergoing postoperative rad...

Introduction: In 3DCRT the number of therapeutic fields has dramatic impact on treatment results especially in stomach cancer. Traditionally, for radiotherapy of stomach cancer the therapeutic procedure was using two fields (AP- PA or AP Lateral with wedge) to achieve smooth and homogeneous dose distribution in tumor. But nowadays, adding lateral or oblique fields to aforement...

Introduction: Intensity modulated radiation therapy (IMRT) and three-dimensional conformal radiation therapy (3D CRT) are two treatment modalities in prostate cancer, which provide acceptable dose distribution in tumor region with sparing the surrounding normal tissues. IMRT is based on inverse planning optimization; in which, intensity of beams is modified by using multileaf c...

This paper discusses free carrier generation by pulsed laser fields as a mechanism to switch the optical properties of semiconductor photonic crystals and bulk semiconductors on an ultrafast time scale. Requirements are set for the switching magnitude, the time-scale, the induced absorption as well as the spatial homogeneity, in particular for silicon at λ = 1550 nm. Using a nonlinear absorptio...