Recently, we proposed a self-propelled particle model with competing alignment interactions: nearby particles tend to align their velocities whereas they anti-align their direction of motion with particles which are further away [R. Großmann et al., Phys. Rev. Lett. 113, 258104 (2014)]. Here, we extend our previous numerical analysis of the high density regime considering low particle densities...

Serine capped dipeptide N-acetyl-l-serinamide (Ac-Ser-NH2) has been investigated using Fourier transform microwave spectroscopic techniques combined with laser ablation sources. Spectral signatures originating from one dominant species have been detected in the supersonic expansion. Rotational and nuclear quadrupole coupling constants of the two (14)N nuclei have been used in the characterizati...

Facial features detection is of primary importance to face authentication and recognition. In this paper, we present an attention{driven approach to eyes and mouth detection inspired by the human saccadic system. The algorithm is centred around a log{polar retinotopic grid that is used to sample the Gabor decomposition of the image. Detection is achieved by displacing the grid according to a sa...

Tomographic imaging provides a powerful technique for obtaining images of the spatial distribution of ionospheric electron density at polar latitudes. The method, which involves monitoring radio transmissions from the Navy Navigation Satellite System at a meridional chain of ground receivers, has particular potential for complementing temporal measurements by other observing techniques such as ...

The pattern of recent surface warming observed in the Arctic exhibits both polar amplification and a strong relation with trends in the Arctic Oscillation mode of atmospheric circulation. Paleoclimate analyses indicate that Arctic surface temperatures were higher during the 20th century than during the preceding few centuries and that polar amplification is a common feature of the past. Paleocl...

Organic aerosols are ubiquitous in the earth's atmosphere. They have been extensively studied in urban, rural and marine environments. However, little is known about the fluorescence properties of water-soluble organic carbon (WSOC) or their transport to and distribution in the polar regions. Here, we present evidence that fluorescent WSOC is a substantial component of High Arctic aerosols. The...

1. introduction the position of iran in the subtropical region that has made its arid and semiarid climate and the topographic diversity changes this trend of climate. therefore, climate hazards such as frost, flood, dust storm, drought, temperature anomalies, heavy rainfall, avalanches, snow, sleet, etc occur in iran. the northwest of iran experiences the above conditions following the arrival...

This is a pioneering work, introducing special class of complex numbers, wherein their absolute values and arguments given in Polar coordinate system are integers, which when considered within the plane, constitute Unicentered Radial Lattice similarly for quaternions Euclidean R2 R3 Spaces. The corresponding Optimization Problems introduced as well.