This work examines the relationship between 3-year pedestrian crash counts across Census tracts in Austin, Texas, and various land use, network, and demographic attributes, such as land use balance, residents' access to commercial land uses, sidewalk density, lane-mile densities (by roadway class), and population and employment densities (by type). The model specification allows for region-spec...

Continuum and emission-line variability of active galactic nuclei provides a powerful probe of microarcsecond scale structures in the central regions of these sources. In this contribution, we review basic concepts and methodologies used in analyzing AGN variability. We develop from first principles the basics of reverberation mapping, and pay special attention to emission-line transfer functio...

Combining Doppler and polarimetric information is advantageous for atmospheric studies. On the one hand, Doppler information gives insight into the microphysical and dynamic properties of radar targets, that is, radial velocity and its variability. The polarization diversity, on the other hand, has a strong link to the microphysical properties of targets such as shape and orientation. Polarimet...

We study the detectability of the cross-correlation between 21 cm emission from the intergalactic medium and the galaxy distribution during (and before) reionization. We show that first-generation 21 cm experiments, such as the Mileura Widefield Array (MWA), can measure the cross-correlation to a precision of several percent on scales k ∼ 0.1 Mpc if combined with a deep galaxy survey detecting ...

We have examined simultaneous X-ray and optical light curves of a sample of eight nearby Seyfert 1 galaxies observed using the EPIC X-ray cameras and Optical Monitor on board XMM-Newton. The observations span ∼ 1 day and revealed optical variability in four of the eight objects studied. In all cases, the X-ray variability amplitude exceeded that of the optical both in fractional and absolute lu...

The results of multicolor photometric and lowresolution spectroscopic observations of 9 Herbig Ae/Be candidate stars are reported. This sample includes two newly recognized objects, MQ Cas and BD+11829, which were found by means of cross-correlation of the IRAS Point Source Catalogue and the catalogue of the galactic early-type emission-line stars (Wackerling 1970). Near-IR excesses were detect...