half-value layer

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half-value layer

[′haf ¦val·yü ‚lā·ər]
(physics)
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
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Until the last epidemiological bulletin of the CGVS, six cases of HVL had been diagnosed and of those four people died.
On HVL data survey, the following outcomes were analysed: age, gender, immunodepression, occupation, area of residence, income, and evolution of the case.
Equation (13) can be written in function of nHVL-times HVL or nTVL-times TVL, with [n.sub.HVL] = [log.sub.2] (1/B) and [N.sub.TVL] = [log.sub.10] (1/B), respectively.
Half-value thickness (HVL) is the thickness of any given material where 50% of the incident energy has been attenuated and has been computed utilizing the linear attenuation coefficient ([) through the following equation:
The IPEMB code of practice for the determination of absorbed dose for x-rays below 300 kV generating potential (0.035 mm Al-4 mm Cu HVL; 10-300 kV generating potential).
avdelningsskotare, Bettina Stenbock-Hult, FD, HVL, PeM, specialsjukskotare, overlarare, programledare for masterprogrammet i halsoframjande.
Using the IPEM Report 78 spectrum generator [16] and our measured HVL of the Rapiscan system of 1.085 mm of Al [13], a value of 0.85 mGy/s is obtained for the air kerma rate at a distance of 75 cm from the source (obtained by multiplying the value of 169.3 [micro]Gy/mAs from the IPEM generator by the Rapiscan tube current of 5 mA).
The half-value layer, HVL (HVL = 0.6932/[mu]), and tenth-value layer, TVL (TVL = 2.303/[mu]), are inversely proportional to [mu] values.
[9.] Barbosa LHF, Ramos HVL, Neves LR, Biase NG, Oshima C, Pedroso JES, Pontes PAL.
Variables affecting the mean glandular dose are the type of image receptor used, the x-ray beam energy (half-value layer, or HVL, and kVp), the degree of breast compression, the breast's size and its adiposity.
(VL) contain nodes that are involved in at least one violation either hard or soft constraint and the second tabu list is called HVL that contain only nodes that are involved in hard constraints.