Abstract: The invention comprises a system for aiding in the in-situ determination of the state of cure (or progress of cure) in bone cement which is a composition that cures in an exothermic reaction and having a device which comprises a frequency sensor joined to a circuit and to an indicator that emits a signal in response to a current emitted to the circuit by the sensor to monitor a state of cure. The invention also relates to surgical methods using the system.

Abstract: A medical devices en-vivo positional determination system and method of surgery using a registration system to create a 3D frame of reference from 2D images and in which the user uses his or her judgement to select points of interest within the 3D frame of reference more accurate hand-held drilling or cutting, using forward kinematic equations calculated on a microcomputer to provide a real-time display of the 3-linear position and 2-angular orientation of a hand-held medical instrument which is linked by a draw wire or a virtual draw wire to a gimbal so as to measure the angle and distance of the instrument from a fixed point.

Abstract: The invention comprises a system for aiding in the in-situ determination of the state of cure (or progress of cure) in bone cement which is a composition that cures in an exothermic reaction and having a device which comprises a frequency sensor joined to a circuit and to an indicator that emits a signal in response to a current emitted to the circuit by the sensor to monitor a state of cure. The invention also relates to surgical methods using the system.

Abstract: The invention comprises a system which determines the cure status of bone cement which is then used in making surgical decisions on the cement use and further comprises a system for aiding in securing an implant to a bone using a cured grout or bone cement. The system includes a device which comprises a frequency sensor joined to a circuit to monitor one or more frequency signals, and to an indicator that emits a signal in response to a current emitted to the circuit by the system while monitoring the state of cure. The invention also relates to surgical methods using the system.

Abstract: The invention comprises a system for securing an implant to a bone comprising an implant which is affixed to the bone, a grout or bone cement comprising a composition that cures in an exothermic reaction and which is capable of securing the implant to the bone in a cured state, and a tester which measures temperature over time to detect a rate change of temperature and uses a novel discrete differentiator circuit to determine when the composition reaches cure.

Abstract: The invention comprises a system for securing an implant to a bone comprising an implant which is affixed to the bone, a grout or bone cement comprising a composition that cures in an exothermic reaction and which is capable of securing the implant to the bone in a cured state, a device which provides access to the grout or bone cement in position on the bone and a tester which measures temperature over time to detect the exothermic reaction so as to determine when the composition reaches cure. The tester comprises a sensor joined to a circuit and to an indicator that emits a signal in response to a current emitted to the circuit by the sensor.

Abstract: A medical devices en-vivo positional determination system using a plurality of optical time of flight (TDF) transceivers along with gyroscopic angular and mechanical distance sensors for the determination of absolute linear and angular positional information of the tool bit tip for the purposes of more accurate hand-held drilling or cutting, on the workpiece using forward kinematic equations calculated on a microcomputer to provide a real-time display of the 3-linear position and 2-angular orientation of the tool bit (such as a drill, scalpel, or wire driver).

Abstract: A medical device en-vivo positional determination system using a plurality of ultrasonic transducers for the time-of-flight (TOF) determination of absolute linear and angular positional information of the tool bit tip for the purposes of more accurate hand-held drilling, cutting, etc. on the work piece using digital code modulation schemes and digital signal processing (DSP) to provide a real-time display of the 3-linear position and 2-angular orientation of the tool bit (drill, scalpel).

Abstract: A means of detecting the in-situ fuel-to-air-ratio (FAR) in a combustor or flame zone using a Fourier-based flame ionization probe is presented. The use of multiple excitation frequencies and its detection at certain frequencies or combinations of harmonics of those excitation frequencies, namely, the inter-modulation distortion, provides a novel means of extracting a high signal-to-noise ratio (SNR) FAR measurement in a combustor.

Abstract: A means of detecting the in-situ fuel-to-air-ratio (FAR) in a combustor or flame zone using a Fourier-based flame ionization probe is presented. The use of multiple excitation frequencies and its detection at certain frequencies or combinations of harmonics of those excitation frequencies, namely, the inter-modulation distortion, provides a novel means of extracting a high signal-to-noise ratio (SNR) FAR measurement in a combustor.

Abstract: A means of detecting the in-situ fuel-to-air-ratio (FAR) in a combustor or flame zone using a Fourier-based flame ionization probe is presented. The use of multiple excitation frequencies and its detection at certain frequencies or combinations of harmonics of those excitation frequencies, namely, the inter-modulation distortion, provides a novel means of extracting a high signal-to-noise ratio (SNR) FAR measurement in a combustor.

Abstract: A means of detecting the in-situ fuel-to-air-ratio (FAR) in a combustor or flame zone using a Fourier-based flame ionization probe is presented. The use of multiple excitation frequencies and its detection at certain frequencies or combinations of harmonics of those excitation frequencies, namely, the inter-modulation distortion, provides a novel means of extracting a high signal-to-noise ratio (SNR) FAR measurement in a combustor.

Abstract: The invention relates a horn-based multi-driver wide-bandwidth loudspeaker with a flat-frequency response having the property of controlled acoustic directivity at wavelengths larger than the nominal wavelength supported by the horns' mouth circumference which is provided by means of a centerbody fitted with acoustic drivers that are acoustically coupled to the walls of the horn enclosure.

Abstract: The invention relates a horn-based multi-driver wide-bandwidth loudspeaker with a flat-frequency response having the property of controlled acoustic directivity at wavelengths larger than the nominal wavelength supported by the horns' mouth circumference which is provided by means of a centerbody fitted with acoustic drivers that are acoustically coupled to the walls of the horn enclosure.

Abstract: The invention is a compact high fidelity sound reproduction system achieving high efficiency, low distortion, wide bandwidth, and extended low frequency reach and which can be used as a sub-bass woofer, bass woofer, mid-bass woofer, and mid-range speaker for residential or commercial large venue applications. The system includes a dynamic driver driven bass horn, a looped resonator duct (ring geometry), which can be folded, and an adjustable feedback duct allowing sound characteristics to be tailored.

Abstract: The invention is a compact high fidelity sound reproduction system achieving high efficiency, low distortion, wide bandwidth, and extended low frequency reach and which can be used as a sub-bass woofer, bass woofer, mid-bass woofer, and mid-range speaker for residential or commercial large venue applications. The system includes a dynamic driver driven bass horn, a looped resonator duct (ring geometry), which can be folded, and an adjustable feedback duct allowing sound characteristics to be tailored.

Abstract: A system and method is disclosed wherein optical signals are coded in a transmitter by tuning or modulating the interbeam delay time (which modulates the fourth-order coherence) between pairs of entangled photons. The photon pairs are either absorbed or not absorbed (transparent) by an atomic or molecular fluorescer in a receiver, depending on the inter-beam delay that is introduced in the entangled photon pairs. Upon the absorption, corresponding fluorescent optical emissions follow at a certain wavelength, which are then detected by a photon detector. The advantage of the disclosed system is that it eliminates a need of a coincidence counter to realize the entanglement-based secure optical communications because the absorber acts as a coincidence counter for entangled photon pairs.

Abstract: An architecture for spontaneous Raman scattering (SRS) that utilizes a frame-transfer charge-coupled device (CCD) sensor operating in a subframe burst gating mode to realize time-resolved combustion diagnostics is disclosed. The technique permits all-electronic optical gating with microsecond shutter speeds (<5 ?s), without compromising optical throughput or image fidelity. When used in conjunction with a pair of orthogonally-polarized excitation lasers, the technique measures time-resolved vibrational Raman scattering that is minimally contaminated by problematic optical background noise.

Abstract: A low-emissions high-pressure multi-fuel burner includes a fuel inlet, for receiving a fuel, an oxidizer inlet, for receiving an oxidizer gas, an injector plate, having a plurality of nozzles that are aligned with premix face of the injector plate, the plurality of nozzles in communication with the fuel and oxidizer inlets and each nozzle providing flow for one of the fuel and the oxidizer gas and an impingement-cooled face, parallel to the premix face of the injector plate and forming a micro-premix chamber between the impingement-cooled face and the in injector face. The fuel and the oxidizer gas are mixed in the micro-premix chamber through impingement-enhanced mixing of flows of the fuel and the oxidizer gas. The burner can be used for low-emissions fuel-lean fully-premixed, or fuel-rich fully-premixed hydrogen-air combustion, or for combustion with other gases such as methane or other hydrocarbons, or even liquid fuels.

Abstract: An optical pulse stretcher and a mathematical algorithm for the detailed calculation of its design and performance is disclosed. The optical pulse stretcher has a plurality of optical cavities, having multiple optical reflectors such that an optical path length in each of the optical cavities is different. The optical pulse stretcher also has a plurality of beam splitters, each of which intercepts a portion of an input optical beam and diverts the portion into one of the plurality of optical cavities. The input optical beam is stretched and a power of an output beam is reduced after passing through the optical pulse stretcher and the placement of the plurality of optical cavities and beam splitters is optimized through a model that takes into account optical beam divergence and alignment in the pluralities of the optical cavities.