Abstract: The present invention is an energy generating system for a telecommunications megasite which uses fuel cells and capacitors to backup a commercially available primary source of power.

Abstract: The present invention is an energy generating system which uses an advanced aqueous-electrolyte energy storage system in conjunction with a commercial available primary source of power and a backup fuel cell.

Abstract: Disclosed is a power system which uses a fuel cell. DC output from the fuel cell is inverted to power an air conditioner. The air conditioner is used for the purpose of cooling equipment in the facility in the event the primary source of AC power fails. The air conditioner is located so that it is devoted to one or more computing devices in the facility. The selected devices are ones which perform some critical function, e.g., emergency communications.

Abstract: The present invention is a power system using a reformer/fuel cell arrangement as the primary source of DC power. The reformer is operated on either natural gas or propane. A backup source of power consumes hydrogen which is diffused from a solid medium. On an as-needed basis, the medium is reacted to release hydrogen gas which is consumed by a fuel cell to generate backup DC power. The system also includes Lithium-Metal-Polymer batteries which are used for both bridging and backup purposes.

Abstract: The present invention is a power system using a reformer/fuel cell arrangement as the primary source of power. The reformer is operated on either natural gas or propane. A backup source of power comprises a fuel cell which operates on stored hydrogen. The system also includes capacitors which are used to bridge when the system is transferred from the primary source to the backup source.

Abstract: The present invention is a DC power system incorporated into a modular housing. The primary source of power is an electrical utility. Because the electrical utility provides alternating current, the module includes a rectifier which makes the conversion to DC. The module also includes an air turbine which is used as a backup source of power. Also included is an array of lithium-metal-polymer (LMP) batteries to bridge and also for backup power if necessary.

Abstract: The present invention is a modular power system using a fuel cell as a back-up power supply. The system includes lithium-metal-polymer (LMP) batteries to bridge and also for backup power if necessary. The entire system is preassembled ready for use so that it is available to a new or expanding site upon delivery. The total number of modular units used can simply be aggregated to meet additional power demanded.

Abstract: The present invention is an energy generating system which uses Lithium Metal Polymer (LMP) batteries in conjunction with a microturbine, a fuel cell, and commercial electrical power. The LMPs provide uninterruptible power when one or more of the other power systems fail.

Abstract: The present invention is a mobile-energy generating system. It comprises a turbine, a fuel cell, commercial electrical power hookups, capacitors used for bridging purposes, and hydrogen-storage tanks. Pressurized hydrogen is maintained in the tanks using a hydrogen liberator which is optionally powered by a solar panel.

Abstract: The present invention is a mobile-energy generating system capable of providing redundant direct current power. It comprises a reciprocating engine and generator having dual fuel capability, a fuel cell, commercial electrical power hookups, and capacitors used for bridging purposes. Back-up fuel for the engine and fuel for the fuel cells are stored in propane and hydrogen storage tanks, respectively.

Abstract: A photonic-crystal distributed-feedback laser includes a laser cavity with a waveguide structure that has a cavity length Lc and is bounded by two mirrors; an active region for producing optical gain upon receiving optical pumping or an input voltage; at least one layer having a periodic two-dimensional grating with modulation of a modal refractive index, the grating being defined on a rectangular lattice with a first period along a first axis of the grating and a second period along a second perpendicular axis of the grating, and wherein the grating produces three diffraction processes having coupling coefficients ?1?, ?2?, ?3?; and a lateral gain area contained within a second area patterned with the grating that has substantially a shape of a gain stripe with a width W, with the gain stripe tilted at a first tilt angle relative to the two mirrors.

Abstract: Semiconductor optoelectronic devices such as diode lasers are formed on InP substrates with an active region with an InAsN or InGaAsN electron quantum well layer and a GaAsSb or InGaAsSb hole quantum well layer which form a type II quantum well. The active region may be incorporated in various devices to provide light emission at relatively long wavelengths, including light emitting diodes, amplifiers, surface emitting lasers and edge-emitting lasers.

Abstract: A method for calculating the beam quality and output wavelength spectrum of a photonic crystal distributed feedback laser includes the steps of calculating at least two coupling coefficients and forming a characteristic matrix; repeating the following steps at spaced increments of time until a steady state solution is reached: repeating the following steps for one of the incremental cavity lengths: calculating a gain change and a modal refractive index change for the laser waveguide structure for one incremental stripe width; calculating a spontaneous emission term for the gain change; calculating a gain roll-off term for the gain change; applying the gain change, the modal refractive index change, the spontaneous emission term, and the gain roll-off term to at least two forward-propagating beams and at least two backward-propagating beams for the one incremental stripe width; performing a Fourier transformation with respect to the one incremental stripe width to yield a plurality of diffraction terms; adding

Abstract: A surface-emitting photonic crystal distributed feedback laser apparatus configured to emit an optical beam of light. The apparatus includes a laser cavity bounded by top and bottom optical claddings, an active region configured to produce optical gain upon receiving optical or electrical pumping, a periodic two-dimensional grating having an order higher than the fundamental and configured to induce modulation of a modal refractive index, and lateral pumped gain area contained within an area covered by the grating, the lateral pumped gain area configured to produce gain in one or more lasing modes having a modal index modulated by the grating. The lateral pumped gain area has a substantially circular shape of diameter D, and wherein the pumped gain area is enclosed by an unpumped region contained within the area covered by the grating but not receiving the optical or electrical pumping.

Abstract: A surface-emitting photonic crystal distributed feedback laser apparatus configured to emit an optical beam of light. The apparatus includes a laser cavity bounded by top and bottom optical claddings, an active region configured to produce optical gain upon receiving optical or electrical pumping, a periodic two-dimensional grating having an order higher than the fundamental and configured to induce modulation of a modal refractive index, and lateral pumped gain area contained within an area covered by the grating, the lateral pumped gain area configured to produce gain in one or more lasing modes having a modal index modulated by the grating. The lateral pumped gain area has a substantially circular shape of diameter D, and wherein the pumped gain area is enclosed by an unpumped region contained within the area covered by the grating but not receiving the optical or electrical pumping.

Abstract: A method for calculating the beam quality and output wavelength spectrum of a photonic crystal distributed feedback laser includes the steps of calculating at least two coupling coefficients and forming a characteristic matrix; repeating the following steps at spaced increments of time until a steady state solution is reached: repeating the following steps for one of the incremental cavity lengths: calculating a gain change and a modal refractive index change for the laser waveguide structure for one incremental stripe width; calculating a spontaneous emission term for the gain change; calculating a gain roll-off term for the gain change; applying the gain change, the modal refractive index change, the spontaneous emission term, and the gain roll-off term to at least two forward-propagating beams and at least two backward-propagating beams for the one incremental stripe width; performing a Fourier transformation with respect to the one incremental stripe width to yield a plurality of diffraction terms; adding

Abstract: A photonic-crystal distributed-feedback laser includes a laser cavity with a waveguide structure that has a cavity length Lc and is bounded by two mirrors; an active region for producing optical gain upon receiving optical pumping or an input voltage; at least one layer having a periodic two-dimensional grating with modulation of a modal refractive index, the grating being defined on a rectangular lattice with a first period along a first axis of the grating and a second period along a second perpendicular axis of the grating, and wherein the grating produces three diffraction processes having coupling coefficients &kgr;1′, &kgr;2′, &kgr;3′; and a lateral gain area contained within a second area patterned with the grating that has substantially a shape of a gain stripe with a width W, with the gain stripe tilted at a first tilt angle relative to the two mirrors.

Abstract: A configuration that promotes cleaner fracture by reducing or eliminating secondary fractures includes a plurality of distinct interconnecting regions defining a plurality of separate fracture regions that are separated by an interruption.

Abstract: A gain region for an interban quantum well laser incudes (a) an emitter ron of semiconductor material having at least one conduction subband and at least one valence subband, these subbands being spaced apart by an energy band-gap; (b) a collector region of semiconductor material having at least one conduction subband and at least one valence subband, these subbands spaced apart by an energy band-gap; (c) a type-I or type-II active region; and (d) a blocking quantum well region of semiconductor material between the active region and the collector region, for keeping electrons in the active region from tunnelling or scattering into the collector region, but allowing electrons in the highest valence subband in the active region to pass into the collector region.