The ray effect in ray tracing method was analyzed and three new ray emitting methods for a surface element (method A, B and C) were presented. Numerical computations of viewfactors for three different typical configurations indicated that the proposed methods can significantly eliminate the ray effect. Compared with the conventional ray emitting method, the proposed methods, especially method C...

soil samples were collected from seven sites in and around the metropolitan area of mexicocity. the locations were chosen as possible sources of fugitive dusts which contribute to suspended particulate matter in the atmosphere of mexico city. x-ray fluorescence (xrf) was used to determine the concentrations of several major elements (si, k, ca, ti, mn, and fe), as well as of other trace element...

  Background: The sporadic cases of radiation-activated multiple sclerosis (MS) has been previously described, with a few studies focused on the relationship between radiation and the risk of MS. The aim of our study was to evaluate the association between history of X-ray radiation and MS.   Methods : This case-control study was conducted on 150 individuals including 65 MS patients and 85 age-...

Introduction: Unfolding X-ray spectrum is a powerful tool for quality control of X-ray tubes. Generally, the acquisition of the X-ray spectrum in diagnostic radiology departments is complicated and difficult due to high photon flux. Measurement of x ray spectra using radiation detectors could not be performed accurately, because of the pulse pile up. Therefore, indirect methods...

background: bisphosphonates (bps) are used extensively for managing the osteoporosis. there are some controversies on atypical fractures of femur that associated with increase in cortical thickness (ct) and bps' use. in this study, the effects of alendronate consumption were studied on femoral ct as a predictor for atypical fracture.   methods: forty nine post-menopausal women aged 50-70 years ...

Abstract The Earth's magnetosheath and cusps are the sources of soft X‐rays. In accompanying paper (Part 1) this paper, we discuss methods finding magnetopause position by analyzing X‐ray images. We use software developed for Soft Imager (SXI) on board forthcoming Solar wind Magnetosphere Ionosphere Link Explorer (SMILE) mission. show how to find maximum SXI count rate in noisy maps. verify ass...

this study is aimed to identify sources of particulate matter with mean aerodynamic diameterbelow 10 μm (pm10) present in the atmosphere of the metropolitan area of mexico city (mamc), usingsamples obtained from january 1st to june 30th, 2009, analyzed with x-ray spectrometric techniques.minivol samplers were used to collect samples on polycarbonate filters in three sites (north, center, andsou...