Large-Scale Mapping of Human Activity using Geo-Tagged Videos

This paper is the first work to perform spatio-temporal mapping of human activity using the visual content of geo-tagged videos. We utilize a recent deep-learning based video analysis framework, termed hidden two-stream networks, to recognize a range of activities in YouTube videos. This framework is efficient and can run in real time or faster which is important for recognizing events as they occur in streaming video or for reducing latency in analyzing already captured video. This is, in turn, important for using video in smart-city applications. We perform a series of experiments to show our approach is able to accurately map activities both spatially and temporally. We also demonstrate the advantages of using the visual content over the tags/titles.Comment: Accepted at ACM SIGSPATIAL 201

Modelling Aging Characteristics in Citation Networks

Growing network models with preferential attachment dependent on both age and degree are proposed to simulate certain features of citation network noted in \cite{red2}. In this directed network, a new node gets attached to an older node with the probability $\sim K(k)f(t)$ where the degree and age of the older node are $k$ and $t$ respectively. Several functional forms of $K(k)$ and $f(t)$ have been considered. The desirable features of the citation network can be reproduced with $K(k) \sim k^{-\beta}$ and $f(t) \sim \exp(\alpha t)$ with $\beta =2.0$ and $\alpha = -0.2$ and with simple modifications in the growth scheme.Comment: 6 pages, 6 figure

Electromagnetic decays of vector mesons as derived from QCD sum rules

We apply the method of QCD sum rules in the presence of external electromagnetic fields $F_{\mu\nu}$ to the problem of the electromagnetic decays of various vector mesons, such as $\rho\to\pi\gamma$, $K^\ast\to K\gamma$ and $\eta'\to\rho\gamma$. The induced condensates obtained previously from the study of baryon magnetic moments are adopted, thereby ensuring the parameter-free nature of the present calculation. Further consistency is reinforced by invoking various QCD sum rules for the meson masses. The numerical results on the various radiative decays agree very well with the experimental data.Comment: To appear in Phys. Lett.

catena-Poly[[[diaquacadmium(II)]bis[μ-2-(pyridinium-1-yl)butanedioato]-κ2 O 1:O 4;κ2 O 4:O 1] tetrahydrate], a polymeric chain structure

In the title complex, {[Cd(C9H8NO4)2(H2O)2]·4H2O}n, the CdII atom (site symmetry 2) is coordinated by six O atoms from four crystallographically related 1-(1,2-dicarboxyl­ate)pyridin-1-ium ligands (L) and from two water molecules in a distorted octahedral geometry. Paired L ligands connect CdII atoms into a chain motif parallel to [001], which is further inter­linked by O—H⋯O hydrogen bonds into a three-dimensional supra­molecular net