Automatic fall incident detection in compressed video for intelligent homecare

[[abstract]]This paper presents a compressed-domain fall incident detection scheme for intelligent homecare applications. First, a compressed-domain object segmentation scheme is performed to extract moving objects based on global motion estimation and local motion clustering. After detecting the moving objects, three compressed-domain features of each object are then extracted for identifying and locating fall incidents. The proposed system can differentiate fall-down from squatting by taking into account the event duration. Our experiments show that the proposed method can correctly detect fall incidents in real time.[[fileno]]2030144030047[[department]]電機工程學

Bis[4′-(4-cyano­phen­yl)-2,2′:6′,2′′-terpyridine]cobalt(II) dichloride

The title complex, [Co(C22H14N4)2]Cl2, has been synthesized by a solvothermal reaction of the 4′-(4-cyano­phen­yl)-2,2′:6′,2′′-terpyridine ligand with CoCl2·6H2O. The cobalt(II) ion is six-coordinated by two tridentate ligands in a distorted octa­hedral geometry. The benzene rings form dihedral angles of 30.02 (7) and 30.26 (7)° with the mean planes of the terpyridine ring systems. The chloride anions are statistically disordered over two positions with refined site occupancies of 0.601 (2) and 0.399 (2)

Characteristics of profiles of gamma-ray burst pulses associated with the Doppler effect of fireballs

In this paper, we derive in a much detail the formula of count rates, in terms of the integral of time, of gamma-ray bursts in the framework of fireballs, where the Doppler effect of the expanding fireball surface is the key factor to be concerned. Effects arising from the limit of the time delay due to the limited regions of the emitting areas in the fireball surface and other factors are investigated. Our analysis shows that the formula of the count rate of fireballs can be expressed as a function of $\tau$ which is the observation time scale relative to the dynamical time scale of the fireball. The profile of light curves of fireballs depends only on the relative time scale, entirely independent of the real time scale and the real size of the objects. It displays in detail how a cutoff tail, or a turn over, feature (called a cutoff tail problem) in the decay phase of a light curve can be formed. This feature is a consequence of a hot spot in the fireball surface, moving towards the observer, and was observed in a few cases previously. By performing fits to the count rate light curves of six sample sources, we show how to obtain some physical parameters from the observed profile of the count rate of GRBs. In addition, the analysis reveals that the Doppler effect of fireballs could lead to a power law relationship between the $FWHM$ of pulses and energy, which were observed previously by many authors.Comment: 38 pages, 10 figures; accepted for publication in ApJ (10 December 2004, v617

Individual position diversity in dependence socioeconomic networks increases economic output

The availability of big data recorded from massively multiplayer online role-playing games (MMORPGs) allows us to gain a deeper understanding of the potential connection between individuals' network positions and their economic outputs. We use a statistical filtering method to construct dependence networks from weighted friendship networks of individuals. We investigate the 30 distinct motif positions in the 13 directed triadic motifs which represent microscopic dependences among individuals. Based on the structural similarity of motif positions, we further classify individuals into different groups. The node position diversity of individuals is found to be positively correlated with their economic outputs. We also find that the economic outputs of leaf nodes are significantly lower than that of the other nodes in the same motif. Our findings shed light on understanding the influence of network structure on economic activities and outputs in socioeconomic system.Comment: 19 pages, 5 figure

Observation of backscattering-immune chiral electromagnetic modes without time reversal breaking

A strategy is proposed to realize robust transport in time reversal invariant photonic system. Using numerical simulation and microwave experiment, we demonstrate that a chiral guided mode in the channel of a three-dimensional dielectric woodpile photonic crystal is immune to the scattering of a square patch of metal or dielectric inserted to block the channel. The chirality based robust transport can be realized in nonmagnetic dielectric materials without any external field.Comment: 16 pages, 5 figure

Poly[[tetra-μ2-aqua-diaqua-μ6-oxalato-barium(II)] 2,4,6-trinitro­phenolate monohydrate]. Corrigendum

Corrigendum to Acta Cryst. (2007), E63, o2296

A redetermination of bis­(5,5′-diethyl­barbiturato)bis­(imidazole)cobalt(II)

The title complex, [Co(C8H12N2O3)2(C3H4N2)2], whose structure was first determined by Wang & Craven [(1971). J. Chem. Soc. D, pp. 290–291], has been redetermined with improved precision. A crystallographic twofold rotation axis passes through the Co atom, which is tetrahedrally coordinated by two N atoms from two barbital ligands and two N atoms from two imidazole ligands. The mol­ecules are self-assembled via inter­molecular N—H⋯O hydrogen-bonding inter­actions into a supra­molecular network

4-(Imidazol-1-yl)benzoic acid

In the title mol­ecule, C10H8N2O2, the imidazole and benzene rings form a dihedral angle of 14.5 (1)°. In the crystal, inter­molecular O—H⋯N hydrogen bonds link the mol­ecules into chains extending in [01], which are further linked into sheets parallel to (102) through weak C—H⋯O inter­actions