With the advent of GPS for control surveying, a problem has arisen. Many existing control stations established by conventional methods (i.e. first order triangulation stations) are in locations not suitable for direct occupation by GPS equipment. Eccentric observations are often possible, with the eccentric station located up to 100 m away. In order to connect the eccentric station to the main ...

Sound localization depends on multiple acoustic cues such as interaural differences in time (ITD) and level (ILD) and spectral features introduced by the pinnae. Although many neurons in the inferior colliculus (IC) are sensitive to the direction of sound sources in free field, the acoustic cues underlying this sensitivity are unknown. To approach this question, we recorded the responses of IC ...

The classical methods for synthetic aperture radar (SAR) azimuth ambiguity suppression are based on deterministic methodologies. However, the reconstruction with azimuth ambiguity problem is underdetermined. In this paper, we present a group sparse modeling based approach in which the reflectivity of target is extended as group sparse signal and its components are jointly recovered by lq regula...

The on-orbit alignment of the antenna beams of both the X-band and C-band radar systems during operations of the shuttle radar topography mission/X-band synthetic aperture radar (SRTM/X-SAR) was a key requirement for achieving best interferometric performance. In this paper, we consider the X-SAR antenna beam alignment in azimuth. For a single-pass cross-track SAR interferometer, we establish t...

The Medium-Earth-Orbit SAR (MEOSAR) is one of the most potential next-generation spaceborne SARs for its excellent performances. However, the MEOSAR may not be able to produce data useful for science applications due to ionospheric effects. So it is very necessary to study ionospheric effects for the development of MEOSAR. In this paper, we present ionospheric effects on azimuth imaging for MEO...

Accommodation and convergence systems are cross-coupled so that stimulation of one system produces responses by both systems. Ideally, the cross-coupled responses of accommodation and convergence match their respective stimuli. When expressed in diopters and meter angles, respectively, stimuli for accommodation and convergence are equal in the mid-sagittal plane when viewed with symmetrical con...

There is evidence that human observers are more sensitive to the direction-of-heading of point-light walkers defined by first-order than second-order motions. We addressed this question by measuring the minimum direction difference (azimuth) that observers could discriminate when the dots composing the walkers were conveyed by first or second-order motions. Sensitivity to azimuth differences fo...

Previous studies have demonstrated large errors (over 30 degrees ) in visually perceived exocentric directions (the direction between two objects that are both displaced from the observer's location; e.g., Philbeck et al. [Philbeck, J. W., Sargent, J., Arthur, J. C., & Dopkins, S. (2008). Large manual pointing errors, but accurate verbal reports, for indications of target azimuth. Perception, 3...