When resources collide: Towards a theory of coincidence in information spaces

This paper is an attempt to lay out foundations for a general theory of coincidence in information spaces such as the World Wide Web, expanding on existing work on bursty structures in document streams and information cascades. We elaborate on the hypothesis that every resource that is published in an information space, enters a temporary interaction with another resource once a unique explicit or implicit reference between the two is found. This thought is motivated by Erwin Shroedingers notion of entanglement between quantum systems. We present a generic information cascade model that exploits only the temporal order of information sharing activities, combined with inherent properties of the shared information resources. The approach was applied to data from the world's largest online citizen science platform Zooniverse and we report about findings of this case study

Fe-doping induced superconductivity in charge-density-wave system 1T-TaS2

We report the interplay between charge-density-wave (CDW) and superconductivity of 1$T$-Fe$_{x}$Ta$_{1-x}$S$_{2}$ ($0\leq x \leq 0.05$) single crystals. The CDW order is gradually suppressed by Fe-doping, accompanied by the disappearance of pseudogap/Mott-gap as shown by the density functional theory (DFT) calculations. The superconducting state develops at low temperatures within the CDW state for the samples with the moderate doping levels. The superconductivity strongly depends on $x$ within a narrow range, and the maximum superconducting transition temperature is 2.8 K as $x=0.02$. We propose that the induced superconductivity and CDW phases are separated in real space. For high doping level ($x>0.04$), the Anderson localization (AL) state appears, resulting in a large increase of resistivity. We present a complete electronic phase diagram of 1$T$-Fe$_{x}$Ta$_{1-x}$S$_{2}$ system that shows a dome-like $T_{c}(x)$

Self-organized criticality in the intermediate phase of rigidity percolation

Experimental results for covalent glasses have highlighted the existence of a new self-organized phase due to the tendency of glass networks to minimize internal stress. Recently, we have shown that an equilibrated self-organized two-dimensional lattice-based model also possesses an intermediate phase in which a percolating rigid cluster exists with a probability between zero and one, depending on the average coordination of the network. In this paper, we study the properties of this intermediate phase in more detail. We find that microscopic perturbations, such as the addition or removal of a single bond, can affect the rigidity of macroscopic regions of the network, in particular, creating or destroying percolation. This, together with a power-law distribution of rigid cluster sizes, suggests that the system is maintained in a critical state on the rigid/floppy boundary throughout the intermediate phase, a behavior similar to self-organized criticality, but, remarkably, in a thermodynamically equilibrated state. The distinction between percolating and non-percolating networks appears physically meaningless, even though the percolating cluster, when it exists, takes up a finite fraction of the network. We point out both similarities and differences between the intermediate phase and the critical point of ordinary percolation models without self-organization. Our results are consistent with an interpretation of recent experiments on the pressure dependence of Raman frequencies in chalcogenide glasses in terms of network homogeneity.Comment: 20 pages, 18 figure

Comparison of RF Penetration and G-factor of Different Coil Arrays for Parallel Imaging

Geometry factor and RF penetration of different kinds of coil arrays for parallel imaging were evaluated by simulations using MATLAB and XFDTD software. The results show that the coil arrays with loop structure are superior to the planar strip arrays in terms of g-map and RF penetration. The overlapped loop array has better RF penetration, while the non-overlapped one has a lower noise level in parallel imaging.published_or_final_versio

Market concentration, risk-taking, and bank performance: evidence from emerging economies

This paper investigates the relationship between market concentration, risk-taking, and bank performance using a unique dataset of the BRIC banks over the period 2003-2010. We find a negative association between market concentration and performance, in support of the “quiet life” hypothesis. We also find that banks taking a lower level of risks perform better, in favour of prudential practice. Moreover, the BRICs’ banking sectors were all negatively affected by the 2007-2008 global financial crisis with China and Russia being the least and most affected, respectively. On average Chinese and Brazilian banks outperform Indian and Russian ones, indicating that China and Brazil have more favourable institutional infrastructure. These results are robust to alternative model specifications and estimation techniques. Our analysis may have important policy implications for bankers and regulators in the BRICs and other developing and transition countries

A Direct Modulated Optical Link for MR Coil Array Interconnect

A direct modulated optical link for MR coil array interconnect has been developed. The link uses a diode laser to modulate RF signals directly, and needs only one fiber for each channel. It has a power gain of ¨C18dB, noise figure of 29dB and dynamic range of 110dBHz. The noise figure can be reduced to below 1dB by a low noise preamp. Compared with an external modulated optical link, a direct modulated link has simpler link structure, lower cost and more compact size, so it is more advantageous for large coil array interconnect.published_or_final_versio

Noise Figure and Dynamic Range Optimization in Optical Links for MRI Applications

MRI applications impose critical requirements in noise figure and dynamic range for optical links used for coil interconnect. To reduce the intrinsic high noise figure of optical links, a low-noise preamp must be used. But it also brings the side effect of dynamic range reduction. Compromise must be made between noise figure and dynamic range to optimize the optical link to meet the critical requirement in MRI. Dynamic range of the current optical link is still a challenge for high field imaging above 3T and needs to be further improved.published_or_final_versio

Mass movement susceptibility mapping using satellite optical imagery compared with InSAR monitoring: Zigui County, Three Gorges region, China

Mass movements on steep slopes are a major hazard to communities and infrastructure in the Three Gorges region, China. Developing susceptibility maps of mass movements is therefore very important in both current and future land use planning. This study employed satellite optical imagery and an ASTER GDEM (15 m) to derive various parameters (namely geology; slope gradient; proximity to drainage networks and proximity to lineaments) in order to create a GIS-based map of mass movement susceptibility. This map was then evaluated using highly accurate deformation signals processed using the Persistent Scatterer (PS) InSAR technique. Areas of high susceptibility correspond well to points of high subsidence, which provides a strong support of our susceptibility map