Health physics
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When assessing the power emitted from a Wi-Fi network, it has been observed that these networks operate at a relatively low duty cycle. In this paper, we extend a recently introduced model of emitted power in Wi-Fi networks to cover conditions where devices do not always have packets to transmit. ⋯ Moreover, we confirm that the greatest power is emitted when the network is saturated with traffic. Using this, we give a simple technique to quickly estimate power output based on traffic levels and give examples showing how this might be used in practice to predict current or future power output from a Wi-Fi network.
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Standard-setting agencies such as the U. S. Nuclear Regulatory Commission and the U. ⋯ As long as the policy-decision environment is characterized by high scientific uncertainty and a lack of values consensus, advisory groups should present unbiased evaluations of all scientifically plausible alternatives and recommend selection criteria that decision makers can use in the policy-setting process. To do otherwise (e.g., by serving as single position advocates) weakens decision-making by eliminating options and narrowing discussions of scientific perspectives. Understanding uncertainties and the limitations on available scientific information and conveying such information to policy makers remain key challenges for the technical and policy communities.
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Many pregnant women are exposed to radiation either as a patient or as an employee. Ignorance of the issues surrounding the radiation exposure of pregnant females is encountered among medical and other professionals, often leading to undue concern. The exposure of pregnant patients has to be justified and the risk/benefit carefully assessed. ⋯ Pregnant females working with radiation also need separate consideration and careful monitoring. The author has personal experience of this working as an interventional radiologist throughout pregnancy. Education of professionals working with radiation and in medicine is essential and international organizations in radiation protection should continue to provide and support this role.
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In the past decade, various radiation reducing devices and control circuits have been implemented on fluoroscopic imaging equipment. Because of the potential for lengthy fluoroscopic procedures in interventional cardiovascular angiography, these devices and control circuits have been developed for the cardiac catheterization laboratories and interventional angiography suites. Additionally, fluoroscopic systems equipped with image intensifiers have benefited from technological advances in x-ray tube, x-ray generator, and spectral shaping filter technologies. ⋯ This includes various types of fluoroscopic systems designed to strive for reduction of patient exposure with the application of spectral shaping filters. The main thrust is to understand the ADRIQ control logic, through equipment testing, as it relates to clinical applications, and to show how this ADRIQ control logic "ties" those three technological advancements together to provide low radiation dose to the patient with high quality fluoroscopic images. Finally, rotational angiography with computed tomography (CT) and three dimensional (3-D) images utilizing flat panel technology will be reviewed as they pertain to diagnostic imaging in cardiovascular disease.
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New technologies such as intensity modulated and image guided radiation therapy, computer controlled linear accelerators, record and verify systems, electronic charts, and digital imaging have revolutionized radiation therapy over the past 10-15 y. Quality assurance (QA) as historically practiced and as recommended in reports such as American Association of Physicists in Medicine Task Groups 40 and 53 needs to be updated to address the increasing complexity and computerization of radiotherapy equipment, and the increased quantity of data defining a treatment plan and treatment delivery. While new technology has reduced the probability of many types of medical events, seeing new types of errors caused by improper use of new technology, communication failures between computers, corrupted or erroneous computer data files, and "software bugs" are now being seen. ⋯ More commonly they are a combination of computer and human errors. The increased use of radiosurgery, hypofractionation, more complex intensity modulated treatment plans, image guided radiation therapy, and increasing financial pressures to treat more patients in less time will continue to fuel this reliance on high technology and complex computer software. Clinical practitioners and regulatory agencies are beginning to realize that QA for new technologies is a major challenge and poses dangers different in nature than what are historically familiar.