background: in order to assign appropriate planning target volume (ptv) margins, each centre should measure the patient positioning deviations for their set-up techniques. at the royal marsden hospital, uk, a conformal shell (cast) system is used when a stereotactic frame is not suitable. in this paper, we report on a series of measurements with the aim of obtaining the systematic and random co...

ground vibrations during an earthquake can severely damage structures and equipments housed in them. many factors including earthquake magnitude, distance from the fault or epicenter, duration of strong shaking, soil condition of the site, and the frequency content of the motion define the properties of ground motion and its amplification. a deep understanding of the effects of these factors on...

Background Baseline offset errors on phase-contrast velocity images can be corrected using stationary tissue, for example subtracting fitted corrections from the image (1). Although corrections are often curved over the FOV, 1st order (linear) fitting is typical. This may partly be due to low SNR of static tissue making higher-order fitting unreliable (2). Aim: To evaluate a new method acquirin...

Barnes et al. (1) described a flame photometer and various authors have since analyzed the sources of errors in the technique and made various suggestions for eliminating them (2-12). These investigators have been primarily concerned with the design and operation of the instrument, the interference of one substance with another, and similar problems. The purpose of the present investigation was...

Com mercial stat ic strain indicators and signal conditioners vary considerably in their circuit details; and, although most of them are based upon some form of the Wheatstone bridge circuit, the bridge circuit is employed in differing ways in different instruments. Because of the many variations in instrument design, a completely general treatment of instrument nonlinearities is not practicabl...