In this paper, we propose a novel distributed localization scheme LDB, a 3D localization scheme with directional beacons for Underwater Acoustic Sensor Networks (UWA-SNs). LDB localizes sensor nodes using an Autonomous Underwater Vehicle (AUV) as a mobile beacon sender. Mounted with a directional transceiver which creates conical shaped directional acoustic beam, the AUV patrols over the 3D dep...

We report on a new articular cartilage imaging technique with potential for clinical arthroscopic use, by supplementing the variable-incidence-angle polarization-sensitive optical coherence tomography method previously developed by us with a conical beam scan protocol. The technique is validated on bovine tendon by comparing experimental data with simulated data generated using the extended Jon...

We construct near-infrared to visible broad band NICMOS/WFPC color maps for 4 early-type Seyfert galaxies with S-shaped or one-sided ionization cones. We find that dust lanes are near or connected to many of the features seen in the [OIII] and Hα+[NII] line emission maps. This suggests that much of the structure of line emission in these ionization cones is determined by the distribution of amb...

Phenomena of nonlinear light-matter interaction that occur during the propagation of intense ultrashort laser pulses in continuous media have been extensively studied in ultrafast optical science. In this vibrant research field, conversion of the input laser beam into optical filament(s) is commonly encountered. Here, we demonstrate generation of distinctive single or double super-luminescent o...

We describe a novel secondary-electron ion microscope (SEIM), designed for diagnostics of the upcoming submicron Columbia University charged-particle microbeam. This secondary-electron ion microscope allows much higher resolutions, at higher single particle detection efficiencies, than previously available, for rapid and accurate diagnostics of sub-micron charged-particle beams. Based on ion el...

Abstract. Time-harmonic oscillations of a horizontal plate generate internal gravity waves in an unbounded stratified fluid. A plane-wave (Fourier) decomposition is used in which waves with outgoing group velocity are selected. The pressure and the velocity in the far field are estimated in terms of the Fourier transform of the pressure jump across the plate. Explicit solutions are obtained for...

Few-moded or over-moded horns are now being proposed for far-IR space receiver systems, e.g. the High Frequency Instrument (HFI) on the ESA PLANCK Surveyor. In such systems individual waveguide modes can couple independently to an overmoded detector (such as a bolometer in an integrating cavity). We consider in detail the case of a cylindrically symmetric configuration consisting of a corrugate...

The study of conical refraction for media other than biaxial non-magnetic crystals has never been considered in the literature – as far as the authors are aware. Hence, in this paper, we investigate how conical refraction can arise for broader classes of biaxial metamaterials using a new classification scheme previously developed by the authors. Namely, conical refraction is shown to occur for ...

We report a novel phenomenon of spontaneous formation of nearly regular arrays of nanospikes atop conical microstructures by exposing a germanium surface to femtosecond laser pulses in an environment of SF6. Silicon laser texturing has been reported, but no information has been published on laser microtexturing of Ge and in particular the observation of nanospikes atop conical microstructures. ...

The Alpha Magnetic Spectrometer (AMS), to be installed on the International Space Station (ISS) in 2008, is a cosmic ray detector with several subsystems, one of which is a proximity focusing Ring Imaging Čerenkov (RICH) detector. This detector will be equipped with a dual radiator (aerogel+NaF), a lateral conical mirror and a detection plane made of 680 photomultipliers and light guides, enabl...