Abstract: A feedback method on occasion independently senses a characteristic of light produced by each of several light sources in a lighting apparatus. The sensed value of that characteristic is compared to a reference value for the respective light source and that light source's operation is adjusted accordingly. This method has particular application in a lighting apparatus that produces different lighting effects by varying the intensity of different colors of light produced by the various light sources. The feedback method compensates for light emission variation as the sources age, thus ensuring that the lighting apparatus continues to produce the desired lighting effects. This enables multiple lighting apparatus in an area to be calibrated to the same standard so that uniform illumination is provided.

Abstract: A lighting apparatus includes a first source of monochromatic light, a second source of white light, and a third source of polychromatic light. The light from the three sources combine to produce a resultant color of light from the apparatus. The intensities of the light emitted by the first, second and third sources are independently controlled by a controller to produce a desired resultant color of light. Varying the amount of electric current applied to each such light source by substantially an equal amounts to changes the luminance of the combined light with out affecting the resultant color. The lighting apparatus can be operated to replicate a Planckian radiator with a color rendering index of at least 80 throughout a substantial portion of the visible light spectrum produced by the lighting apparatus.

Abstract: An optical element is provided that may be used for collecting optical radiation incident at large angles of incidence. The element may include a grating window formed of grating elements that may collect large incident angle radiation and reflect that radiation, e.g., under total internal reflection in a substantially normal direction. A lens or lens array may be used to collect the internally reflected radiation and focus that radiation to a detector. Example detectors include infrared detectors. The element may be formed to collect, reflect, and redirect optical radiation incident at angles above 45° as measured from a surface normal to a detector oriented substantially at normal incidence. The detected signal from the optical element may be used to control systems within an aircraft or other vehicle capable of flight.

Abstract: A heat-dissipating, light-reflecting plate for a radiator of a spacecraft is provided. The heat-dissipating, light-reflecting plate has an at least partially transparent, thermally conductive layer and a plurality of first light-reflecting surfaces disposed proximate to the at least partially transparent, thermally conductive layer. A plurality of second light-reflecting surfaces also is disposed proximate to the at least partially transparent, thermally conductive layer. At least a first sub-set of the plurality of second light-reflecting surfaces is oriented at a first angle to at least a first sub-set of the plurality of first light-reflecting surfaces.

Abstract: An electrical power converter receives input power of one type or level at input terminals and supplies output power of another type or level at output terminals. The power converter includes a high frequency transformer, an input circuit connected between the input terminals and the primary of the transformer, and an output circuit connected between the secondary of the transformer and the output terminals, a controller for controlling pulse width of current pulses produced by the input circuit, and a current limiting circuit.

Abstract: A power converter for converting DC to AC power or DC to DC power includes an input circuit, a transformer, an output circuit, and a controller. The input circuit receives DC input power and creates high frequency pulses. The transformer transforms the high frequency pulses into at least two sets of transformed pulses, the sets of transformed pulses having alternating and opposite polarity. The transformer includes a primary winding and a secondary winding, where the primary winding is connected to the input circuit. The output circuit includes a plurality of switches for providing a full wave rectified or DC output, where the output circuit is connected to the secondary winding. The controller controls the switches to provide a continuous current path through the output circuit thus minimizing voltage spikes and ripple, and greatly reducing the cost and complexity of the output circuit usually required to handle these spikes and ripple.

Abstract: A large area heater used, for example, in a laser printer belt fuser or as cooking surface, has an alumina substrate in which two bowed parts of alumina ceramic having opposed concave regions are formed together as a laminate. Electrical resistors are deposited on the laminate. The alumina laminate provides excellent resistance to uneven heating or other thermal stress. Alumina ceramic is readily shaped during manufacture and manufacturing costs and yield are good. A wide variety of large area heaters can usefully employ the laminate.

Abstract: A method for calculating and displaying the isothermal contours of the energy produced by a laser in a sample includes applying a laser beam to the focal point of a sample. The region near the focal point is divided into cylinders coaxial with the beam. The maximum temperature reached during the laser pulse of at least three points at arbitrary distances from the focal point is derived. The temperatures calculated are plotted as a function of distance from the focal point sufficient to generate isothermal contours. A computer display is then generated of the isothermal contours corresponding to the temperature calculations.

Abstract: A container for storing and transporting semen, e.g., equine semen, along with a corresponding method of packing the container, is provided. The container is formed of an insulated box and an insulated cover. The insulated box and insulated cover each includes a collection of ridges and recesses to create a friction fit between the two that will only work with the insulated cover being placed on the insulated box in a predetermined orientation. A cooling pack is disposed on a floor of the insulated box. An insert is disposed to rest on the cooling pack inside the insulated box, such that the cooling pack is beneath the insert when the insulated box is in an upright position. The insert has at least one chamber for receiving a storage capsule holding the semen sample. The insulated cover frictionally fits on the insulated box and makes contact with the insert to hold the insert in place.

Abstract: A method and apparatus for detecting a channel jammed by narrowband jamming interference in a block oriented digital transmission system such as an orthogonal frequency division multiplexing (OFDM) or discrete multi-tone (DMT) system. A spectrum of a received data bearing signal is examined to identify areas of the spectrum that are likely corrupted by a narrowband jamming interference. The method identifies jammed channels by applying a boxcar filter, in order to identify narrow peaks in the spectrum that are substantially larger in magnitude than adjacent channels. Channels identified as jammed or affected by a jamming signal, are listed in a jam mask used for screening out corrupted channels during data transmission.

Abstract: A method and system for estimating a time shift required for symbol synchronization in a block oriented digital communication systems such as an orthogonal frequency division multiplexing (OFDM) or a discrete multi-tone (DMT) data transmission system. The method uses an N/d inverse discrete Fourier transform (IDFT), where N is a sample number and d is a decimation factor, or alternatively an N/(2d) inverse fast Fourier transform (IFFT) for a real received signal or an N/d IDFT for a complex received signal.

Abstract: A system and method for delivering content on-demand by way of a cable network are disclosed. Provision of such content is controlled over a data network. Advantageously, a user interface at a conventional computing device may be used to order content and to control its delivery and playing. Commands from the computing device may be provided by way of data network to a network interconnected server. The server under software control causes a media receiver at the customer premises to be properly tuned to receive content on-demand, and content on-demand to be played, as requested by the computing device. The media receiver may include a conventional set-top box that may be tuned remotely in response to a customer placing an on-demand order.

Abstract: An optical injection system for use in conjunction with a microscope having a turret supporting an objective having an optical path is provided. The optical injection system includes a dichroic mirror disposed between the turret and the objective, along the optical path. A collimating lens is further provided having an optical path directed to intersect the dichroic mirror. A laser source is positioned to project a laser beam through the collimating lens and along the collimating lens optical path. The laser can be used in conjunction with the microscope for a number of microsurgery applications. A method for calculating and displaying the isothermal contours of the energy produced by a laser in a sample is also provided.

Abstract: A container for storing and transporting semen, e.g., equine semen, along with a corresponding method of packing the container, is provided. The container is formed of an insulated box and an insulated cover. The insulated box and insulated cover each includes a collection of ridges and recesses to create a friction fit between the two that will only work with the insulated cover being placed on the insulated box in a predetermined orientation. A cooling pack is disposed on a floor of the insulated box. An insert is disposed to rest on the cooling pack inside the insulated box, such that the cooling pack is beneath the insert when the insulated box is in an upright position. The insert has at least one chamber for receiving a storage capsule holding the semen sample. The insulated cover frictionally fits on the insulated box and makes contact with the insert to hold the insert in place.

Abstract: A method and apparatus for selecting a modulation type and forward error correction (FEC) configuration and a sub-carrier map to maximize data throughput in a multi-carrier orthogonal frequency division multiplexing (OFDM) system for use in an inherently noisy network, such as power line distribution networks. A sub-carrier map or is constructed by selecting a sub-set of available sub-carriers using estimated sub-carrier SNR values and two predefined criteria, a SNR threshold and a useful sub-carrier ratio. The invention leverages the error correction capacity of FEC to maximize data throughput.

Abstract: A navigation and routing system for a domain to be navigated and including a plurality of nodes comprising, at each node, a passive element the identity of which is unique to the address of the associated node, and an active navigation device programmed with an electronic map of the domain and capable of receiving information from the passive elements, the arrangement being such that, for any given destination within the domain, and on reading of the passive element at a first node by the navigation device, routing information is displayed by the navigation device to direct the user to the next node in the route leading to his destination.

Abstract: A cassette reader for detecting the status of stained samples is provided. The colorimeter includes one or more high power emitting diodes as the source of illuminating the sample. An elliptical mirror, with a central aperture to permit the light to penetrate on to the sample, directs the scattered light on to its focal point at a detector. The colorimeter includes a microprocessor which compares an output signal for the percent ratio value of the detected values of a sample and a standard sample. The colorimeter housing provides position sensors which allow the identification of the well being examined. Finally, the system is modified to measure cell motility by determining the ratio of motile sperms to total cell concentration.

Abstract: A navigation and routing system for a domain to be navigated and including a plurality of nodes comprising, at each node, a passive element the identity of which is unique to the address of the associated node, and an active navigation device programmed with an electronic map of the domain and capable of receiving information from the passive elements, the arrangement being such that, for any given destination within the domain, and on reading of the passive element at a first node by the navigation device, routing information is displayed by the navigation device to direct the user to the next node in the route leading to his destination.

Abstract: A method of operating an intruder detector system comprising deploying plural intruder sensors in or adjacent a region to be protected, transmitting signals from each sensor to a processor, the signals relating to at least one local environmental ambient condition, processing the signals to determine a common ambient condition associated with the intruder sensors, transmitting a control signal to each of the sensors, and automatically adjusting the sensors in response to the control signal to substantially vary detection parameters thereof.

Abstract: A memory bandwidth allocation scheme in a computer system having a unified memory architecture. When a first device requesting access to a resource detects that two higher priority devices are also requesting access to the same resource, the first device shuts itself down. Accordingly, the first device deactivates its access request signals and clears its buffers. Then, the first device reactivates itself when it receives a graphics VSYNC signal. This allocation scheme ensures that the arbiter will not get stuck in a loop serving only high priority requests and not serving lower priority requests.