SUMMARY The paper investigates efficiency of different shielding techniques. The study was performed on the basis of 3-D substation model design where the finite-element method for calculation of magnetic fields (the EMAS software) was used and measurements were performed. The study was designed to meet the following objectives: − to obtain a useful analytical tool for evaluation of magnetic fi...

PURPOSE Ionizing radiation is implicated in nearly 2% of malignancies in the United States; radiation shields prevent unnecessary radiation exposure during medical imaging. Contemporary radiation shield utilization for adult patients in the United States is poorly defined. Therefore, we evaluated the prevalence of protective shielding utilization in adult patients undergoing CT scans in United ...

The relationship between surface transfer impedance and stirred mode chamber shielding effectiveness proposed by Eicher and Boillot has been simplified. This simplified relationship was used to compare the measured stirred mode chamber shielding effectiveness of nine shielding artifacts with the shielding effectiveness of the same samples calculated from transfer impedance measurements made at ...

normal 0 false false false en-us x-none fa introduction: in radiation therapy centers across iran, protection of normal tissues is usually accomplished by either cerrobend or lead block shielding. in this study, the influence of these two shielding methods on central axis dose distribution of photon beam a cobalt unit was investigated in clinical conditions. materials and methods: all measureme...

............................................................................................................. 8 I. Theoretical Background .................................................................... 9 Cognitive Control ............................................................................................................ 10 An Introduction to Cognitive Control.........................

Using 40 ns laser pulses, we probe the real-time dynamics of ultracold ionizing collisions in metastable xenon. We time resolve both shielding and enhancement effects, and observe the production of Xe2 molecular ions through associative ionization. We estimate the rate of molecule formation in excited-state collisions, and directly measure the role of both flux enhancement and excited state sur...

Shielding calculations are done for the following scenario: a graphite target is hit by a 1 GeV/u U beam with an intensity of 10 particles per second. The target is a wheel with radius of 22.5 cm and it is subdivided into three rings, each 16 mm wide, with thicknesses of 21.6, 32.4 and 43.2 mm, corresponding to 4, 6, 8 g/cm [3]. For a conservative case the thickest part of the target with a thi...

Applying shielding coils is a practical way to protect current transformers (CTs) for large-capacity generators from the intensive magnetic interference produced by adjacent bus-bars. The aim of this study is to build a simple analytical model for the shielding coils, from which the optimization of the shielding coils can be calculated effectively. Based on an existing stray flux model, a new a...

in this paper, shielding effectiveness (se) of a perforated enclosure with imperfectly conducting walls is evaluated. to this end, first, an accurate numerical technique based on method of moments (mom) ispresented. in this method, lossy metallic walls of the enclosure are replaced by equivalent electric surfacecurrent sources. then, the impedance boundary condition on the imperfectly conductin...

Background: Gonad shielding has been recommended during pelvic x-rays since the 1950s. The popular method of gonad shielding is placement a lead shield in the midline of the pelvis. The aim of this study was to evaluate the prevalence and utility of gonad shielding in pediatrics undergoing pelvic x-rays.Materials and MethodsFollowing study approval, we retrospectively retrieved data from the di...