Abstract: A method of training a TTS or other system to assign intonational features, such as intonational phrase boundaries, is described. The method of training involves taking a set of predetermined text (not speech or a signal representative of speech) and having a human annotate it with intonational feature annotations. This results in annotated text. Next, the structure of the set of predetermined text is analyzed to generate information. This information is used, along with the intonational feature annotations, to generate a statistical representation. The statistical representation may then be stored and repeatedly used to generate synthesized speech from new sets of input text without training the TTS system further.

Abstract: The invention presents a method and apparatus for forming a restricted model from a system model to reduce the computational resources required to formally verify the system design, without substantially reducing the ability to test all system model functions, or properties. In general, the restricted model is formed by restricting the range of assumable values of system model variables and system model inputs to a restricted set of values, based on the values assumed by the system model variables and system model inputs during a partial search of the system model. The restricted model can then be fully searched by a conventional verification tool to identify system design errors. Advantageously, the restricted model requires less computational resources during a fall search than the original system model.

Abstract: A system and method for selectively controlling database access by providing a system and method that allows a network administrator or manager to restrict specific system users from accessing information from certain public or otherwise uncontrolled databases (i.e., the WWW and the Internet). The invention employs a relational database to determine access rights, and this database may be readily updated and modified by an administrator. Within this relational database specific resource identifiers (i.e., URLs) are classified as being in a particular access group. The relational database is arranged so that for each user of the system a request for a particular resource will only be passed on from the local network to a server providing a link to the public/uncontrolled database if the resource identifier is in an access group for which the user has been assigned specific permissions by an administrator. The invention is implemented as part of a proxy server within the user's local network.

Abstract: A thermionic cathode having an overcoating of emissive material having a position including a mixture Aluminum Tungstate and Scandium Tungstate which react, when heated, to provide the cathode with enhanced electron emissions.

Abstract: A simplified method of making permanent magnet structures, such as magic rings and magic spheres, from a uniformly magnetized permanent magnet shell. Thus, through the inventive method, building such structures requires only one remanence. For example, to make a magic ring providing a uniform internal magnetic field that can be accessed through non-distorting ports, a uniformly magnetized cylindrical shall is cut into ultra-thin washer shaped pieces. One half of the washer shaped pieces are radially cut into pie shaped pieces. The pie shaped pieces of each sliced-up washer-shaped piece are then rotated or transposed to form ultra-thin magic ring slices. The magic ring slices are then alternately stacked with the remaining washer shaped pieces to form a magic ring having predetermined regions wherein the shell magnetization is zeroized. Thus, the shell material in these regions can be removed to provide distortion-free access to the internal field.

Abstract: A permanent magnet structure providing an internal magnetic field having an djustable magnitude and direction. The structure utilizes a shell composed of a predetermined number of concentric permanent magnet cylinders, each of which generates a discrete tunable magnetic field for tuning the magnitude and direction of the internal working field. Depending on the magnitude and direction of each discrete magnetic field, the magnitude and direction of the working field can be controlled and adjusted as desired.

Abstract: This invention provides a method for substantially reducing the time drift f a network clock in a frequency hopping communications system, without the need for a master unit to keep network time. The automatic network time tracking mechanism of each receiver is disabled when a network time update is received within a critical period of time from the closest synchronization update time or frequency hop time. The critical period is defined as the time between the closest synchronization update time to the local time when reception occurs less one-half the minimum tracking adjustment of the receiver plus the minimum processing or decoding delay, and that closest synchronization update time plus one half the minimum tracking adjustment of the receiver plus the maximum processing or decoding delay.

Abstract: A photon triggered RF radiator that is composed of a photoconductive subste having a ground plane electrode on its bottom surface and a top surface electrode having separate sections to perform energy storage and energy radiation functions. The energy storage section has a bulk-type photoconductive switch position therein such that any energy stored in the energy storage section of the top surface electrode is instantaneously discharged through the substrate to the ground plane, thus causing a pulse of nanosecond pulsewidth dimension to radiate from the energy radiation section of the top surface electrode.

Abstract: A magic sphere that provides a uniform internal field within an enlarged king space that can be accessed from large chambers that penetrate deep into the cavity of the magic sphere without substantially disrupting the magnitude or uniformity of the internal field.

Abstract: A photon triggered RF radiator having separate sections to perform the eny storage and the energy radiation functions. The energy storage function is performed by at least one charging electrode positioned on the upper surface of a photoconductive dielectric substrate, whereas the energy radiation function is performed by a charging electrode positioned adjacent to the charging electrode on the upper surface of the substrate. The charging electrode and the radiating electrode are separated by a predetermined gap distance that is large enough to insure there is no surface flashover between the electrodes and small enough to insure the efficiency of energy discharge from the charging pad to the spiral antenna is maximized.

Abstract: A system that provides an automated simultaneous measurement of the electal characteristics of a ferromagnetic material as a function of temperature and electric potential. The system utilizes a personal computer that interfaces with a DUT fixture through an interface measuring circuit that provides a means for remote control of the measurement process and insures a more timely and less manually intensive measuring process. The interface measuring circuit is composed of a temperature measuring circuit for measuring the temperature applied to the DUT, a capacitor measuring circuit for measuring the electric potential applied to the DUT, a high voltage power supply, a temperature plate power supply, a high voltage power supply driver, a digital voltage meter (DVM), and a DVM multiplexer. The system can utilize a humidity-free "dry" chamber (i.e. a desiccation chamber) to insure that the measurements of the DUT are reliable and accurate.

Abstract: A ferroelectric phase shifter for shifting the phase of a radio frequency F) signal. The phase shifter includes a conductor line, a ground plane and a ferroelectric element between the conductor line and the ground plane to form a microstrip circuit through which the RF signal propagates. The ferroelectric element has a dielectric constant that can be varied as a function of a DC voltage applied to the ferroelectric element wherein the speed of the RF signal propagating through the ferroelectric element is a function of the dielectric constant. The phase shifter further includes a DC voltage source connected across the conductor line and the ground plane. The DC voltage source applies a variable DC voltage to the ferroelectric element in response to a control signal thereby to vary the dielectric constant of the ferroelectric element.

Abstract: A device for measuring the electrical characteristics of a ferromagnetic erial as a function of temperature, such as its dielectric constant verses temperature characteristics. The device having a quick mount fixture that utilizes a gravity feed and thermal grease to insure a quick reliable thermal connection between the temperature controller and the device under test (DUT). In addition, the device can be remotely controlled by a computer to automate the measuring procedure, thus reducing measuring time and alleviating the intensive manual procedure of making such measurements. Moreover, the device is easily mountable in a humidity-free or desiccation chamber to insure the measurements are reliable and accurate.

Abstract: A dual-gate self-oscillating mixer FET that is injection-locked from a remote LO frequency source. The dual-gate FET having a feedback circuit connected between the first gate port and the drain port that is tuned so that the FET can oscillate within a frequency range including a predetermined LO frequency. The FET having a remote synchronization circuit electrically connected to the FET first gate port to inject the predetermined LO frequency therein and lock the FET oscillation to that LO. Accordingly, the dual-gate FET mixes RF energy input to the second gate port with the locked LO injected in the first gate port and outputs the desired intermediate frequency through the drain port.

Abstract: A planar, magnetically-tunable, band-rejection filter comprising a slot-l having at least one magnetically tunable, dielectric resonator-stack positioned on its top surface. The core of each resonator stack is filled with ferrite material. As a result, the filter provides a higher "Q", and thus provides greater suppression of unwanted microwave and millimeter-wave signals than the prior art.

Abstract: A yokeless magnetic circuit composed of a permanent magnet shell having a lenoidal-cavity within which a working field is generated. The permanent magnet shell has a conical permanent end magnet adjacent each of its ends to insure that the surface at each of its ends is equipotential between the radial periphery of the permanent magnet shell and the axial centerpoint of the solenoidal cavity. The height of the conical end magnets directly depends of the magnetization and thickness of the permanent magnet shell and whether the internal field is uniform, gradient or variable.

Abstract: A permanent magnet comprising a shell of magnetic material having a hollow avity and an access port that passes through the shell and communicates with the cavity. The shell is permanently magnetized to produce a magnetic field in the cavity. A magnetic insert is located in the cavity. The insert has a tunnel aligned with the access port and is magnetized in a direction opposite to the direction of the magnetic field. Specifically, a spherical magnetic shell has a concentric cavity in which a spherical magnetic insert is housed. An access port in the form of an axial hole passes through the spherical center of the shell and the insert. The shell ("magic sphere") is magnetized such that it is capable of producing a uniform magnetic field in the cavity. The insert is uniformly magnetized in a direction opposite to that of the cavity field produced by the shell. As such a working field that has a strength greater than that of the cavity field produced by the shell is located in the tunnel.

Abstract: A method for reducing the synchronization overhead in Frequency Hopping communication systems. Generally, the method establishes a synchronization state during which a plurality of communications can take place without re-synchronization before each separate transmission. More particularly, the method establishes a synchronization period during which all the radios are initially synchronized, followed by a series of acknowledgment period and transmission periods during which any unit intending to transmit is assigned a specific time slot for such transmission.

Abstract: A permanent magnet comprising a shell of magnetic material having a hollow avity and an access port that passes through the shell and communicates with the cavity. The shell is permanently magnetized to produce a magnetic field in the cavity. A magnetic insert is located in the cavity. The insert has a tunnel aligned with the access port and is magnetized in a direction opposite to the direction of the magnetic field. Specifically, a spherical magnetic shell has a concentric cavity in which a spherical magnetic insert is housed. An access port in the form of an axial hole passes through the spherical center of the shell and the insert. The shell ("magic sphere") is magnetized such that it is capable of producing a uniform magnetic field in the cavity. The insert is uniformly magnetized in a direction opposite to that of the cavity field produced by the shell. As such a working field that has a strength greater than that of the cavity field produced by the shell is located in the tunnel.

Abstract: A 20 mR (5.16 * 10.sup.-3 C/Kg) full-scale carbon fiber dosimeter that provides a direct reading of low-level Gamma and neutron exposure in real-time. To attain this, the dosimeter utilizes an enlarged ionization chamber that has a cylindrical shape with an inside diameter at least 1 inch (2.54 cm), an outside diameter at least 1.1 inches (2.794 cm), an inside height at least 0.725 inch (1.8415 cm), and an outside at least 1 inch (2.54 cm). Moreover, the inner wall of the dosimeter's ionization chamber is lined with either a predetermined hydrogenous or non-hydrogenous material having different sensitivity to gamma ray and neutron exposure.