This article is concerned with the mechanisms underlying the detection of amplitude modulation (AM), frequency modulation (FM), and mixed modulation (MM), i.e., simultaneously occurring AM and FM. In a previous study [B. C. J. Moore and A. Sek, J. Acoust. Soc. Am. 92, 3119-3131 (1992)], psychometric functions were measured for the detection of AM alone and FM alone, using a 10-Hz sinusoidal mod...

Results of observations of the Galactic bulge X-ray source GX 9+9 by the All-Sky Monitor (ASM) and Proportional Counter Array (PCA) onboard the Rossi X-ray Timing Explorer are presented. The ASM results show that the 4.19 hour X-ray periodicity first reported by Hertz and Wood in 1987 was weak or not detected for most of the mission prior to late 2004, but then became strong and remained strong...

This article is concerned with the detection of mixed modulation (MM), i.e., simultaneously occurring amplitude modulation (AM) and frequency modulation (FM). In experiment 1, an adaptive two-alternative forced-choice task was used to determine thresholds for detecting AM alone. Then, thresholds for detecting FM were determined for stimuli which had a fixed amount of AM in the signal interval o...

We investigate the accuracy and resolution of the variogram analysis method (Maus, 1999) on syn thetic and real data. Syn thetic magnetic ight line data are generated forbasemen t models of idealized geological setups. Comparing variogram depths of the data with true model depths shows that variogram depths are accurate and un biased as long as the data analysis window is larger than 10 times t...

www.americanscientist.org W constitutes a dangerous equation? There are two obvious interpretations: Some equations are dangerous if you know them, and others are dangerous if you do not. The first category may pose danger because the secrets within its bounds open doors behind which lies terrible peril. The obvious winner in this is Einstein’s iconic equation e = mc2, for it provides a measure...