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Smartphone localization is essential to a wide range of applications in shopping malls, museums, office buildings, and other public places. Existing solutions relying on radio fingerprints and/or inertial sensors suffer from large location errors and considerable deployment efforts. We observe an opportunity in the recent trend of increasing numbers of security surveillance cameras installed in indoor spaces to overcome these limitations and revisit the problem of smartphone localization with a fresh perspective. However, fusing vision-based and radio-based systems is non-trivial due to the absence of absolute location, incorrespondence of identification and looseness of sensor fusion. This study proposes iVR, an integrated vision and radio localization system that achieves sub-meter accuracy with indoor semantic maps automatically generated from only two surveillance cameras, superior to precedent systems that require manual map construction or plentiful captured images. iVR employs a particle filter to fuse raw estimates from multiple systems, including vision, radio, and inertial sensor systems. By doing so, iVR outputs enhanced accuracy with zero start-up costs, while overcoming the respective drawbacks of each individual sub-system. We implement iVR on commodity smartphones and validate its performance in five different scenarios. The results show that iVR achieves a remarkable localization accuracy of 0.7m, outperforming the state-of-the-art systems by >70%.

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Crenulatin (C 25 H 20 O 10 ) is a flavonol derivative and has been isolated from the roots of Rhodiola crenulata (Hook. F. et Thoms.), a widely used medicinal herb. Magnesium and calcium cations play an important physiological role in biological systems. In this work, interactions of magnesium and calcium divalent cations with Crenulatin molecule were studied. Density functional theory (DFT) was used to determine coordination geometries and absolute metal ion affinities (MIA) for all possible stable complexes. The results show that calcium and magnesium cations are able to interact with the Crenulatin molecule through mono-, bi-, and tricoordination. B3LYP/ 6-31G(d) bond energies for all complexes reveal that magnesium cation has a greater affinity to Crenulatin molecule than calcium cation. The calculated value of Mg 2+ cation affinity, including the zero-point vibrational energy (ZPE) and basis set superposition error (BSSE), is 231.8 kcal mol -1 for the most stable complex. Entropy (DS) and free energy (DG) variations for the metalation processes considered here have also been reported.

The potential energy curves (PECs) for ground electronic state (X1∑+) and seven excited electronic states (a3∏, A1∏, b3∑+, c3∑+, B1∏, C1∑+, d3∏) of LiAl are obtained using the multi-configuration reference single and double excited configuration interaction method. Equilibrium bond length Re, adiabatic excited energy Te and vertical excited energy Tv are obtained. It is shown that c3∑+ is an unstable repulsive state, A1∏ is a weak bound state and the others are all bound states. Predissociation can be found between b3∑+ and c3∑+ states. Eight electronic states are dissociated along two channels, Li(2S)+Al(2P0) and Li(2P0)+Al(2P0). And then PECs are fitted to analytical Murrell-Sorbie (MS) potential function to deduce the spectroscopic parameters:the Re is 0.2863 nm, ωe is 316 cm-1 and De is 1.03 eV for the ground state; the values of Tv of excited states are 0.27, 0.83, 1.18, 1.14, 1.62, 1.81 and 2.00 eV; the values of De are 1.03, 0.82 and 0.26, repulsive state, 1.54, 1.10, 0.93 eV, and the values of corresponding frequency ωe are 339, 237, 394, repulsive state, 429, 192, 178 cm-1. By solving the radial Schrödinger equation of nuclear motion, the vibration levels, inertial rotation constants (J=0) are reported for the first time.