Abstract: An apparatus and accompanying method to measure fiber twist. The method includes independent determination of fiber bending by measuring strain sensing in outer cores of the same fiber. The apparatus includes a multi-core optical fiber comprising a center core and a plurality of peripheral cores at a distance radially from the center core and running parallel to the center core. The center core includes at least one fiber Bragg grating with polarization-dependent reflectivity. The fiber Bragg grating reflects the launched light as reflected light. The apparatus includes a multi-core optical fiber bend sensing system operable to communicate with the multi-core optical fiber. The multi-core optical fiber bend sensing system is operable to sense a bend in the multi-core optical fiber. The apparatus includes a processor operable to communicate with the polarization controller.

Abstract: A fiber-optic temperature sensor with a cantilever beam including two different material strips with different thermal expansion coefficients, the cantilever beam having a reflective surface on an end of the cantilever beam, an optical fiber probe including a transmitting multimode optical fiber and at least one receiving multimode optical fiber for receiving reflected light from the reflective surface. Temperature changes at the sensor are indicated by a change in reflected light coupled into the receiving multimode optical fiber due to lateral displacement of the edge of the reflective surface caused by bending of the cantilever beam. Some embodiments have additional reference receiving fibers for compensation for noise, changes in gap length, and other factors.

Abstract: The present invention is generally directed to a system for recovering CO2 from seawater or aqueous bicarbonate solutions using a gas permeable membrane with multiple layers. At elevated pressures, gaseous CO2 and bound CO2 in the ionic form of bicarbonate and carbonate diffuse from the seawater or bicarbonate solution through the multiple layers of the membrane. Also disclosed is the related method of recovering CO2 from seawater or aqueous bicarbonate solutions.

Abstract: A computer-implemented method for accurately estimating plasma velocities on the photosphere based on magnetic field data from vector magnetograms. Spatial and temporal derivatives of the magnetic field components are computed and a structure tensor containing terms that specifically include the horizontal magnetic field components is constructed. The structure tensor is convolved with a window function and a least-squares solution based on the convolved structure tensor is found. The solution includes the plasma velocities in the horizontal and vertical directions at the center of the window.

Abstract: A gain medium and an interband cascade laser, having the gain medium are presented. The gain medium can have one or both of the following features: (1) the thicknesses of the one or more hole quantum wells in the hole injector region are reduced commensurate with the thickness of the active hole quantum well in the active quantum well region, so as to place the valence band maximum in the hole injector region at least about 100 meV lower than the valence band maximum in the active hole quantum well; and (2) the thickness of the last well of the electron injector region is between 85 and 110% of the thickness of the first active electron quantum well in the active gain region of the next stage of the medium. A laser incorporating a gain medium in accordance with the present invention can emit in the mid-IR range from about 2.5 to 8 ?m at high temperatures with room-temperature continuous wave operation to wavelengths of at least 4.

Abstract: An apparatus and method for controlling electron flow within a plasma to produce a controlled electron beam is provided. A plasma is formed between a cathode and an acceleration anode. A control anode is connected to the plasma and to the acceleration anode via a switch. If the switch is open, the ions from the plasma flow to the cathode and plasma electrons flow to the acceleration anode. With the acceleration anode suitably transparent and negatively biased with a DC high voltage source, the electrons flowing from the plasma are accelerated to form an electron beam. If the switch is closed, the ions still flow to the cathode but the electrons flow to the control anode rather than the acceleration anode. Consequently, the electron beam is turned off, but the plasma is unaffected. By controlling the opening and closing of the switch, a controlled pulsed electron beam can be generated.

Abstract: A composite material formulated for slow release of a small molecule in seawater includes a porous inorganic oxide framework and micelles embedded within the pores of the framework. The micelles include a surfactant and a small molecule, the surfactant being present in the composite material at no more than 80 parts by weight per 100 parts by weight inorganic oxide, the composite material being stable in seawater for releasing the small molecule over at least 20 days.

Abstract: A transparent polycrystalline ceramic having scattering and absorption loss less than 0.2/cm over a region comprising more than 95% of the originally densified shape and a process for fabricating the same by hot pressing. The ceramic can be any suitable ceramic such as yttria (Y2O3) or scandia (Sc2O3) and can have a doping level of from 0 to 20% and a grain size of greater than 30 ?m, although the grains can also be smaller than 30 ?m. Ceramic nanoparticles can be coated with a sintering aid to minimize direct contact of adjacent ceramic powder particles and then baked at high temperatures to remove impurities from the coated particles. The thus-coated particles can then be densified by hot pressing into the final ceramic product. The invention further provides a transparent polycrystalline ceramic solid-state laser material and a laser using the hot pressed polycrystalline ceramic.

Abstract: A process to deposit a conformal coating of manganese oxide nanocrystals within a high surface area connected pore structure of a carbon paper electrode. A two-step process is utilized. In the first step the carbon paper electrode is immersed in an alkaline manganese oxide solution to form a nanocrystal seed layer on the surface and within the pores of the carbon paper. In the second step the seeded carbon paper is immersed in an acidic manganese oxide solution. The result is a densely packed continuous conformal nanocrystal coating both on the surface of the carbon and deep within its pores. The carbon paper is highly suitable for use as an electrode in a supercapacitor.

Abstract: Disclosed are peptide structures that are stable in aqueous and non-aqueous media where a first linear peptide chain comprising alternating D,L- or L,D-amino acids having an N and C termini is joined by at least one turn region to a second linear peptide chain comprising alternating D,L- or L,D-amino acids having an N and C termini. The peptide chains can be joined at the C terminus of one of the linear peptide chains with an N terminus of the other linear peptide chain, a C terminus of one of the linear peptide chains with a C terminus of the other linear peptide chain, or an N terminus of one of the linear peptide chains with an N terminus of the other linear peptide chain.

Abstract: A system for actively controlling the span-wise rotational twist of a hollow beam along its longitudinal axis, including a hollow beam structure having a leading edge and a trailing edge region, the beam being split along its length, an actuator arranged between split surfaces of the beam, the actuator adapted to move the split surfaces in a longitudinal direction relative to each other, inducing a twist in the beam. In one embodiment, the actuator is a plurality of thermal expansion material blocks alternating with mechanical compression blocks, the thermal expansion material blocks being heated to cause expansion in the spanwise longitudinal direction. Other alternative actuators include a rotary actuators such as a threaded screw, piezoelectric or magnetostrictive blocks, a hydraulic actuator, or a pneumatic actuator. In an embodiment, the beam is an airfoil shape.

Abstract: A high-efficiency white-light-emitting device that includes a polariton light emitter that emits UV or blue light to a down-converting material that converts the polariton emissions to white light. The polariton light emitter includes an active region situated within a resonant optical cavity formed on a substrate. The down-converting material can comprise a luminophoric phosphor or other material. The polariton light and down-converting material can be arranged in a single apparatus to provide a white-light-emitting device that can be used for lighting and instrumentation. The device can also be configured for high-frequency modulation to provide optical signals for communications and control systems.

Abstract: A system and method is provided for using acoustical pulses generated from an airborne laser source to locate objects under water. An array of acoustic sensors, such as passive sonobuoys at the ocean surface, is deployed in known or determinable locations by aircraft. Each area surrounded by acoustic sensors comprises a search cell, within which sonar scattering data can be used to locate objects. Following sonobuoy deployment, the aircraft uses the laser to rapidly generate many laser-acoustic pulse sources within each search cell, which in turn generate spherical acoustic pulses traveling through the water. The acoustic sensors receive the acoustic pulses, either on a direct path or on a scattered path after the pulse strikes an underwater object. The sensors record the acoustic signatures of the received pulses and transmit data of the recorded acoustic pulses to a processor such as processor on a nearby ship.

Abstract: Populations of quantum dots are combined with quantities of a modulator of photoluminescence to produce a plurality of optical barcodes having at least two distinguishable colors arising from varying quantities of a modulator of photoluminescence bound to the populations of quantum dots.

Abstract: Embodiments include systems and methods of non-coherent signal processing. For example, one embodiment includes a method of a non-coherent signal detection. The method includes receiving data indicative of a received signal, and evaluating a probability density function indicative of a signal parameter based on the received data. Evaluating the probability density function comprises identifying at least one of a plurality of terms of summation having at least one peak of the probability density function and evaluating the plurality of terms of a non-central chi-square distribution determining the signal parameter based at least in part on the received data and the calculated probability density.

Abstract: A system and method is provided for using acoustical pulses generated from an airborne laser source to locate objects under water. An array of acoustic sensors, such as passive sonobuoys at the ocean surface, is deployed in known or determinable locations by aircraft. Each area surrounded by acoustic sensors comprises a search cell, within which sonar scattering data can be used to locate objects. Following sonobuoy deployment, the aircraft uses the laser to rapidly generate many laser-acoustic pulse sources within each search cell, which in turn generate spherical acoustic pulses traveling through the water. The acoustic sensors receive the acoustic pulses, either on a direct path or on a scattered path after the pulse strikes an underwater object. The sensors record the acoustic signatures of the received pulses and transmit data of the recorded acoustic pulses to a processor such as processor on a nearby ship.

Abstract: This invention pertains to a composite of AlON and a germanate glass, and to a process for bonding AlON to the glass. The composite includes AlON and glass bonded together and having transmission in the visible and mid-infrared wavelength region. The process includes the step of heating them together above the softening temperature of the glass, the composite having excellent, i.e., typically in excess of about 60%, transmission in the 0.4-5 wavelength region.

Abstract: A method and system for processing analog optical signals to produce a single RF output free from even-order harmonic distortion. Two analog optical signals of different wavelengths ?1, ?2 are input into a dual-output Mach-Zehnder modulator (MZM), where one wavelength input is high-biased and one wavelength is low-biased. The complementary high- and low-biased wavelengths are output from each arm of the MZM to a multiplexer, which filters out the unwanted high- or low-biased wavelengths from each MZM arm so that both wavelengths are low-biased or high-biased. The signals are passed to a pair of photodiodes, and the photocurrents from the photodiodes are differenced to produce the final RF output. Because of the complementary phase differences between the two low- or high-biased signals generating the photocurrent, all components of the photocurrent except the fundamental and odd-order harmonics cancel each other, resulting in a high-quality RF output free from harmonic distortion.

Abstract: A method for simultaneously optimizing a digital image taken in or through a scattering medium and obtaining information regarding optical properties of the scattering medium is provided. Data of the digital image is received by a computer. The digital image is evaluated according to an objective image quality metric and a resulting image quality value is compared to a previously stored image quality value for the image. A revised optical transfer function is derived by modeling the optical properties of the medium to be used to generate a restored digital image, which is derived from the original image and the revised optical transfer function. The restored digital image is evaluated according to the objective image quality metric and an optimized restored image is identified. The optical properties associated with the optical transfer function producing the optimized restored image are retrieved and represent a close approximation of the true optical properties of the medium.

Abstract: An apparatus and method for determining plasma parameters such as plasma electron density ne. The probe apparatus includes an LC resonance probe comprising an inductive element and a capacitive element connected in series. The capacitive element of the probe can be in the form of a parallel plate capacitor, a cylindrical capacitor, a spherical capacitor, or any other suitable capacitor. The configuration of the probe apparatus gives it a characteristic resonance frequency ?R0 which can be determined by a circuit analysis device. When the capacitive element of the probe apparatus is placed in a plasma, the probe exhibits a new resonance frequency ?R, which is different from ?R0 because of the dielectric constant ? of the plasma. The difference in resonance frequencies can be used to determine plasma density ne, where n e = m e ? ? 0 e 2 ? ( ? R 2 - ? R ? ? 0 2 ) .