Nongauge bright soliton of the nonlinear Schrodinger (NLS) equation and a family of generalized NLS equations

We present an approach to the bright soliton solution of the NLS equation from the standpoint of introducing a constant potential term in the equation. We discuss a `nongauge' bright soliton for which both the envelope and the phase depend only on the traveling variable. We also construct a family of generalized NLS equations with solitonic sech^p solutions in the traveling variable and find an exact equivalence with other nonlinear equations, such as the Korteveg-de Vries and Benjamin-Bona-Mahony equations when p=2Comment: ~4 pages, 3 figures, 16 references, published versio

Multimodality in {VR}: {A} Survey

Virtual reality has the potential to change the way we create and consume content in our everyday life. Entertainment, training, design and manufacturing, communication, or advertising are all applications that already benefit from this new medium reaching consumer level. VR is inherently different from traditional media: it offers a more immersive experience, and has the ability to elicit a sense of presence through the place and plausibility illusions. It also gives the user unprecedented capabilities to explore their environment, in contrast with traditional media. In VR, like in the real world, users integrate the multimodal sensory information they receive to create a unified perception of the virtual world. Therefore, the sensory cues that are available in a virtual environment can be leveraged to enhance the final experience. This may include increasing realism, or the sense of presence; predicting or guiding the attention of the user through the experience; or increasing their performance if the experience involves the completion of certain tasks. In this state-of-the-art report, we survey the body of work addressing multimodality in virtual reality, its role and benefits in the final user experience. The works here reviewed thus encompass several fields of research, including computer graphics, human computer interaction, or psychology and perception. Additionally, we give an overview of different applications that leverage multimodal input in areas such as medicine, training and education, or entertainment; we include works in which the integration of multiple sensory information yields significant improvements, demonstrating how multimodality can play a fundamental role in the way VR systems are designed, and VR experiences created and consumed

Studies of CMB structure at Dec=40. II: Analysis and cosmological interpretation

We present a detailed analysis of the cosmic microwave background structure in the Tenerife Dec=+40 degrees data. The effect of local atmospheric contributions on the derived fluctuation amplitude is considered, resulting in an improved separation of the intrinsic CMB signal from noise. Our analysis demonstrates the existence of common structure in independent data scans at 15 and 33 GHz. For the case of fluctuations described by a Gaussian auto-correlation function, a likelihood analysis of our combined results at 15 and 33 GHz implies an intrinsic rms fluctuation level of 48^{+21}_{-15} uK on a coherence scale of 4 degrees; the equivalent analysis for a Harrison-Zel'dovitch model gives a power spectrum normalisation of Q_{rms-ps} = 22^{+10}_{-6} uK. The fluctuation amplitude is seen to be consistent at the 68% confidence level with that reported for the COBE two-year data for primordial fluctuations described by a power law model with a spectral index in the range 1.0 \le n \le 1.6. This limit favours the large scale CMB anisotropy being dominated by scalar fluctuations rather than tensor modes from a gravitational wave background. The large scale Tenerife and COBE results are considered in conjunction with observational results from medium scale experiments in order to place improved limits on the fluctuation spectral index; we find n=1.10 +/- 0.10 assuming standard CDM with H_{0}=50 kms^{-1}Mpc^{-1}.Comment: 10 pages LaTeX, including 8 PostScript figures. Accepted for publication in MNRA

CMB observations with the Jodrell Bank - IAC interferometer at 33 GHz

The paper presents the first results obtained with the Jodrell Bank - IAC two-element 33 GHz interferometer. The instrument was designed to measure the level of the Cosmic Microwave Background (CMB) fluctuations at angular scales of 1 - 2 degrees. The observations analyzed here were taken in a strip of the sky at Dec = +41 deg with an element separation of 16.7 lambda, which gives a maximum sensitivity to ~1.6 deg structures on the sky. The data processing and calibration of the instrument are described. The sensitivity achieved in each of the two channels is 7 micro K per resolution element. A reconstruction of the sky at Dec = +41 deg using a maximum entropy method shows the presence of structure at a high level of significance. A likelihood analysis, assuming a flat CMB spatial power spectrum, gives a best estimate of the level of CMB fluctuations of Delta Tl = 43 (+13,-12) micro K for the range l = 109 +/- 19; the main uncertainty in this result arises from sample variance. We consider that the contamination from the Galaxy is small. These results represent a new determination of the CMB power spectrum on angular scales where previous results show a large scatter; our new results are in agreement with the theoretical predictions of the standard inflationary cold dark matter models.Comment: 11 pages, 11 figures. Web site at http://www.jb.man.ac.uk/research/cmb/ Accepted for publication in MNRA

Realistic Gluino Axion Model Consistent with Supersymmetry Breaking at the TeV Scale

The recently proposed model of using the dynamical phase of the gluino to solve the strong CP problem is shown to admit a specific realization in terms of fundamental singlet superfields, such that the breaking of supersymmetry occurs only at the TeV scale, despite the large axion scale of 10^{9} to 10^{12} GeV. Phenomenological implications are discussed.Comment: 12 pp, 2 fig

Modifying the hydrophobic nature of MAF-6

Using a combination of molecular simulations techniques, we evaluate the structural tunability of the metal azolate framework with zeolitic RHO topology, MAF-6. Two mechanisms are explored to induce hydrophilicity to this hydrophobic material. The study at a molecular level of water adsorption takes place under a variety of conditions. On a first step, we consider water mixtures containing benzene or alcohols, paying special attention to the effect of the size of the alcohol molecules. On a second approach, we analyse the effect of small weight percentages of salt into the MAF-6 on the water adsorption. We first validate the accuracy of the host–guest interactions by reproducing experimental data. A new set of Lennard-Jones parameters for the interaction water- MAF-6 is also provided. The water adsorption behaviour of MAF-6 is studied in terms of adsorption isotherms, heats of adsorption, radial distribution functions, hydrogen bonds formation, and water distribution inside the material. We found that the presence of long molecules of alcohols favours the water adsorption at low values of pressure by smoothing the phase transition of water withing the MAF-6. On the other hand the addition of salt to the structure creates additional adsorption sites for water enhancing its adsorption, while reducing the saturation capacity of the material since the presence of salt reduces the accessible pore volume