Abstract: An artificial underwater habitat is disclosed comprising a structure with a downwardly opening cavity and an upwardly opening cavity including buoyancy means and ballast means. The habitat is preferably constructed in part by used tires. The habitat preferably maintains an upright orientation from the bottom of a body of water to provide an aquatic ecosytem and aquatic food chain at differing depths. The upright orientation of the habitat also minimizes the effect of silting on the habitat. The buoyancy means includes a novel structure for pressurized gas filled containers.

Abstract: A system and method for predistorting a signal which is to be amplified by a non-linear amplifier. The system and method uses additional predistortion circuits to eliminate the predistortion caused by amplifier input circuits and amplifier output circuits. In one aspect of the invention, the system and method uses a frequency response and phase corrector circuit to modify the amplitude versus frequency of the signal independent of phase.

Abstract: A system and method for providing a field configurable radio frequency communication system including an intermediate frequency digital signal processing circuit therefor. The intermediate frequency digital signal processing circuits includes digital transmitter and receiver circuit paths, a digital baseband circuit, control registers and an interface circuit. The transmitter and receiver circuit paths and the baseband circuits include digital processing circuits that are configurable by commands provided to the control register via the interface circuit to select the transmitter or receiver mode of operation, to select the signaling scheme of waveform employed, to configure the signal processing functions of the transmitter or receiver circuit paths, and to select the use of any of a plurality a baseband signal processing functions.

Abstract: A system and method for deploying antenna modules to provide communications within selected areas are disclosed. In the preferred embodiment a base structure is deployed which may be populated with a plurality of antenna modules providing directional communication. As demand for communication services increases, antenna modules may be added to the base structure. The base structure provides for the simplified installation and replacement of antenna modules. Additionally, the base structure provides adjustment in both the horizontal (azimuthal) and vertical (elevation) planes. Multiple ones of the base structure may be deployed in order to provide an enlarged communication area and/or to provide increased communication density within a particular communication area.

Abstract: Methods and apparatus for reducing the bandwidth required to transmit analog information. The analog information is converted to digital data organized in time defined blocks of information called frames. The content of a frame may be modeled as a composite of superimposed objects, which are subsets of information in the frame, that are largely unchanged frame to frame. Each object in a present frame may be represented by an identification of the object and a description of the changes in object-to-frame relationship that occurred from a previous frame to the present frame. The objects in the present frame may then be reconscructed by adjusting the objects in the previous frame in accordance with the change in object-to-frame relationships.

Abstract: A fluorescent lamp containing zinc amalgam and a method of precisely controlling the amount of mercury introduced into a temperature controlled fluorescent lamp. Precise quantities of mercury may be introduced into a fluorescent lamp in the form of solid zinc amalgam pellets that are in a metastable, non-equilibrium state.

Abstract: The present invention provides a self-propelled trailer dump truck which can convey earth and sand at an amount substantially corresponding to two dump trucks by one conveying operation without overloading, whereby excellent effects can be obtained on an economical field and an environmental field. The fixed platform self-propelled trailer TR is provided with a power engine 9 for self-propelling, a mechanism such as a steering system and the like, a dumping mechanism OS for taking off a load and a load box 6 connected to said dumping mechanism OS, wherein an open driver's seat 8 is positioned in front of said load box 6, a trailing member 12 provided in a front end side of a chassis 7 is provided so as to freely rise and fall, and the trailing member 12 is stood up at a time of self-propelling.

Abstract: A system and method for transmitting advanced television signals such as digital television signals. The system and method controls the frequency of the RF signal by compensating for errors in the signal received from a transport system. The system and method also reduces the complexity of the transmission system by inserting a pilot frequency signal after the television signal has been filtered and shaped.

Abstract: A modular digital telephone system and method featuring a universal telephony shelf adaptable for incremental expansion of legacy telephone switches and as a building block in the construction of new telephony switches. The shelf includes identification and connectors for shelf pairing, and is adapted to receive redundant power supplies, plural line cards, and either a peripheral shelf interface unit or a switch array card which provides both a local shelf interface and three interface units for connection to the peripheral interface units of other shelves. System wide fault displays are provided.

Abstract: An optical interference coating on a refractory substrate, the coating being comprised of alternating layers of silicon dioxide and zirconium dioxide. The coating can be in the form of an optical filter where a substrate bearing the coating can be repeatedly cycled between room temperature and a temperature of at least 1000° C. without significant degradation of its optical or mechanical properties.

Abstract: A radially non-deformable surgical access catheter with a central lumen surrounded by plural peripheral lumens, the lumens being rigidly connected to each other to provide axial stiffness for the catheter as well as rotational stiffness for the catheter so that the catheter may be rotated about its longitudinal axis to place the instruments in any of the peripheral lumens into operational proximity to preselected tissue. Methods are also disclosed.

Abstract: A screw has a shank portion (20) provided with a thread (21) and passing over via a transition into a conical tip (22). One or more parallel fins (24) are provided at least in the area of the tip. They are formed with cutting edges (23) and preferably disposed at an angle of inclination (13) of no less than 5° with respect to the longitudinal axis of the screw. The fins (24) project beyond the core diameter (1) of the shank portion (20). The conical tip (22) includes a finless end portion (26). The thread (21), however, extends across the full length of the tip (22).

Abstract: A modular digital telephone system and method featuring a universal telephony shelf adaptable for incremental expansion of legacy telephone switches and as a building block in the construction of new telephony switches. The shelf includes identification and connectors for shelf pairing, and is adapted to receive redundant power supplies, plural line cards, and either a peripheral shelf interface unit or a switch array card which provides both a local shelf interface and three interface units for connection to the peripheral interface units of other shelves. System wide fault displays are provided.

Abstract: A system and method for instantly summoning assistance to the location of an emergency. A mobile unit providing subscriber communications with an operator or emergency service provider includes a beacon signal generator for directing service providers to the location of the emergency. Subscriber communications are established using an existing personal communication system. The beacon signal generator transmits a wideband spread spectrum that is analyzed at receiving stations to determine the location of the mobile unit.

Abstract: A reflector antenna system with multiple feeds each operating in a separate frequency band. The antenna system includes a main parabolic reflector and an ellipsoidal subreflector configured in a Gregorian arrangement. Mutual blockage between the multiple feeds is reduced by their orientation and arrangement. The system includes a transversely positioned feed and an axial feed located in the focal region of the main reflector. The transverse feed may be integral with the subreflector. The system also includes a third feed placed at the virtual focal point of the subreflector.

Abstract: The present invention adapts the 3 tier client/server concept to the legacy switch environment of a prepaid system providing a more highly specialized telephony switch with an improved developmental capacity. Functionality is removed from the switch to an abstraction layer through the use of an integrated network server, permitting the switch to become more specialized. The integrated network server, running Windows NT, supports open platform architecture to meet evolving system needs.

Abstract: Telecommunication equipment is connected to and controlled by a computer which executes software controlling the digital communication between the telecommunication equipment and the computer. Software in the form of a wizard or expert also executes on the computer and acts to simplify the computer user's interaction with the telecommunication equipment and underlying software which controls the telecommunication equipment.

Abstract: A low profile mount for a disc varistor. A thermally sensitive switch is provided both for single and multiple electrode embodiments. The switch may be placed in a shorting circuit and include a spring biased conductor prevented from closure by a heat sensitive element which softens in responsive to excessive heat. The varistor may be fused to prevent excessive current from a short circuited but not open circuited varistor. Methods are also provided.

Abstract: A low profile mount for a disc varistor. A thermally sensitive switch is provided both for single and multiple electrode embodiments. The switch may be placed in a shorting circuit and include a spring biased conductor prevented from closure by a heat sensitive element which softens in responsive to excessive heat. The varistor may be fused to prevent excessive current from a short circuited but not open circuited varistor. Methods are also provided.

Abstract: An object of the present invention is to provide a sealing method by which an excellent bonding may be realized without thermal shock by bonding at a normal temperature due to ultrasonic coupling oscillation to seal a small size of surface mounting type quartz oscillator or the like. A bonding face (1a) of a sealing metal cap (1) is positioned on a bonded face (2a) of a package substrate (2), and ultrasonic oscillations of different directions are simultaneously imparted in the bonding plane while a suitable load is applied from an upper or a lower part of the bonding portion to the plane in a vertical direction so that the sealing metal cap (1) and the package substrate (2) are welded and fixed to be sealed on the bonding face.