Abstract: An apparatus and method for reducing the non-uniformity of a positron emission tomography (“PET”) image is described. The event detector system comprises a detector having a plurality of zones, each zone comprising a plurality of detector devices. The event detector system also comprises a threshold circuit coupled to a detector device of the detector. Additionally, the event detector system comprises a summation circuit coupled to the threshold circuit.

Abstract: A controlled receive device is disclosed having an amplifier circuit, which receives an input signal, and a control circuit which receives the input signal and outputs a controlled signal to a receiver. The receiver outputs an output signal. A controller varies the gain of the amplifier circuit in response to levels of the controlled signal and the output signal. The control circuit outputs a controlled indicator signal indicative of a level of the controlled signal and the receiver outputs an output indicator signal indicative of the output signal level. The controlled indicator signal and the output indicator signal are compared using comparators, to respective reference or threshold levels for producing control signals used by the controller for varying the amplifier gain.

Abstract: An RF integrated circuit includes an improved control circuit for switching between at least two modes of operation, depending upon a characteristic of a signal received by the integrated circuit, the RF integrated circuit including a first input for receiving a first RF signal, when the integrated circuit is in a first mode; a second input for receiving a second input signal when the integrated circuit is in a second mode; and a detector on the integrated circuit couples to the first and second inputs for detecting the presence of the first and second RF signals, and producing an output signal at a logic port of the detector, depending on the state of the first and second RF signals; and a controller on the integrated circuit connected to the detector for switching the integrated circuit between the first mode and the second mode in response to the output signal without the need for the application of an external control signal to the integrated circuit.

Abstract: In the multimedia network, in order to archive or play multimedia data for a production, a multitude of disk file blocks are retrieved from a multitude of files striped across a multitude of disk storage systems through a commutator to the input of an input/output unit. The disk file blocks are copied from the input into disk file blocks in a buffer of the memory of the unit. Then the unit creates a address-size list of data portions in the buffer for archiving the disk files of the production or for playing a multimedia data stream for the production. Then the unit executes a copy command given the address of the list which uses indirection for copying the specified portions of the buffer onto an output of the unit to store the data into an archival tape storage system or to play the production in a multimedia data stream. Also, using the above method, a production may be simultaneously archived and played by the same unit.

Abstract: The present invention is directed to a circuit for performing volume expansion on an audio signal. The circuit includes an amplifier that has an input side and an output side. Further, the amplifier amplifies the audio signal at a first amplification to produce an amplified signal at the output side of the amplifier. The circuit also includes a shunting element coupled across the input side and output side of the amplifier. The shunting element includes a variable impedance device for changing the first amplification of the amplifier to a second amplification if the amplified signal reaches a predetermined threshold.

Abstract: At a seamless splice point, a stream of frames from alternate encoders can be switched to a decoder without causing visually disturbing artifacts, and without causing the decoder's buffer to underflow or overflow. Each encoder's buffer is constrained to lie within an upper and lower bound so as to preclude the underflow or overflow of the decoder buffer, regardless of whether the encoder's stream is switched into or out of the stream to the decoder. By classifying splice points as Entry-only splice points or Exit-only splice points, it is shown that the encoder upper and lower bounds may be relaxed. Furthermore, it is shown that by the appropriate choice of transfer rates for Entry-only and Exit-only points, the permissible size of frames before and after the splice point can be regulated.

Abstract: A graphics controller produces a composite image through selecting between input image pixels, which are designated to be displayed in the same pixel location, by using a select function. The select function is computed on a pixel by pixel basis to provide a select signal that indicates which pixel should be chosen for display as the final composite image on the display screen. The select signal uses mixing key functions to determine which pixel should be passed. The results of these functions are output in the form of key codes. Key codes are combined by performing a logical AND operation between the key codes, and with a Raster OPeration (ROP) code. The ROP code designates which key code combinations are to be logically ORed together to provide an increased number of possible key combinations to determine the selection of the image to be displayed.

Abstract: A video server with a file storage system for a disk drive in which the disk is logically divided into radial zones and sequential portions of files are stored in different zones according to a predetermined order of zones so as to reduce the average seek time during interleaved access to multiple files. When two files are stored with sequential portions of a first file located sequentially around the inside radius of the R/W surface and sequential clusters of a second file located sequentially around the outside radius of the R/W surface and the clusters of the files are read interleaved (taking turns) then the average seek time for reading the files is approximately equal to the maximum seek time. When the sequential clusters of the files are intentionally dispersed in a pattern in the zones, then the average seek time for reading the files is approximately 1/2 the maximum seek time.

Abstract: A motion detection system compares the differences between regions in a reference frame and regions in a subsequent frame to a threshold value. A difference frame is defined containing regions indicating which of the corresponding regions in the subsequent frame exceed the threshold difference when compared to the reference frame. Target and global parameters are defined so that a cluster of regions in the difference frame which indicate above threshold differences, must be greater than the target parameter but less than the global parameter for motion to be deemed to have occurred.

Abstract: A method for improving the adherence of a phosphor screen to the face panel of a color cathode ray tube involves placing a UV reflective filter on the inside of the face panel prior to photolithographic forming of the screen, in order to reflect transmitted UV light back onto those areas form which the light emerged, thereby effectively increasing the exposure dosage of those areas.

Abstract: Doped encapsulated semiconductor nanoparticles of a size (<100 .ANG.) which exhibit quantum effects. The nanoparticles are precipitated and coated with a surfactant by precipitation in an organometallic reaction. The luminescence of the particles may be increased by a further UV curing step.