Two Systems for Direct Radiographic Miniaturization
The direct miniaturization of radiographic images is discussed, and two systems are analyzed in detail. The performance and relative advantages of a large, high-performance X-ray image intensifier (¿18-in or 46-cm diameter) and an optically coupled radiographic intensifier are presented. These systems are estimated to have comparable performance and costs. The X-ray image intensifier system is superior in quantum efficiency and gain, while the radiographic intensifier is superior in contrast. While, as expected, the resolution, contrast, and sensitivity of these systems are not as good as a conventional screen-film cassette system under all circumstances, their performance may be adequate for all but the most demanding radiologic applications.
Absorption and noise in x‐ray phosphors
When the signal in an x‐ray image system is formed by integrating the scintillation pulses rather than by counting them, the signal‐to‐noise ratio is reduced by a factor which depends on the shape of the pulse‐height distribution. The signal‐to‐noise ratio cannot be related directly to either quantum absorption or energy absorption, and a new quantity called noise‐equivalent absorption is defined which bears a simple relationship to the signal‐to‐noise ratio. Quantum, energy, and noise‐equivalent absorption are calculated as a function of thickness and x‐ray energy for CsI, Gd2O2S, LaOBr, Zn0.6Cd0.4S, and CaWO4.
Music and Ethical Responsibility
Introduction 1. Meaning and ethics in music 2. Experiencing music 3. Framing elements of musical experience 4. Improvisation and ethical responsibility 5. Musical improvisation as festival 6. Music, proximity, ethics 7. Ethical responsibility and other people's music Conclusion: ethical responsibility in musical experience.