Abstract: A system capable of stabilizing a tight distribution of threshold voltages of erased flash EEPROM memory cells within a fast time period includes at least one memory cell having source, channel and drain regions on a semiconductor substrate, a floating gate over the channel region on a tunnel oxide layer and a control gate over the floating gate, and a circuit for converging the threshold voltage of an erased memory cell to within a predetermined voltage range. The circuit includes: a driving circuit for applying a first voltage to the control gate and a second voltage between the source and drain regions during the self-convergence operation; and a backbias generator for applying a backbias voltage to the substrate so as to generate hot electrons/holes in the channel region and to inject ones of the hot electrons/holes into the floating gate during the self-convergence operation.

Abstract: The invention provides an article of manufacture comprising a substantially non-immunogenic knee meniscal xenograft for implantation into humans. The invention further provides methods for preparing a knee meniscal xenograft by removing at least a portion of a meniscus from a non-human animal to provide a xenograft; washing the xenograft in saline and alcohol; and subjecting the xenograft to at least one treatment selected from the group consisting of exposure to ultraviolet radiation, immersion in alcohol, ozonation, and freeze/thaw cycling. In addition to or in lieu of the above treatments, the methods include a cellular disruption treatment and glycosidase digestion of carbohydrate moieties of the xenograft followed by treatment of carbohydrate moieties of the xenograft with capping molecules. The invention also provides articles of manufacture produced by one or more of the above-identified methods of the invention.

Abstract: A snowboard includes one or more stiffening plates mounted to the top surface of the snowboard. The plates serve to stiffen localized areas on the snowboard in order to change the flexion and torsion characteristics of the snowboard in that localized area. The location of the stiffening plates can be adjusted to accommodate a wide range of riding stances and orientations. The stiffening plates can be utilized on a symmetrical snowboard to provide asymmetrical flexion and torsion characteristics in order to accommodate the asymmetrical stance of the rider. The stiffening plates can also be adjusted to enable a ski or snowboard to perform well in both soft snow conditions and hard packed snow conditions.

Abstract: In an improved computed tomography scanner drive system and bearing configuration, a gantry disk is sheaved about its perimeter such that the gantry is operable as a driven pulley rotatable about an object to be scanned. A motor assembly mounted to a stationary frame includes a similar sheaved drive pulley. A belt tensioned between the drive pulley of the motor assembly and the driven pulley of the gantry disk transfers rotational motion of the motor to drive the gantry rotationally about the object. In a preferred embodiment, the belt comprises a V-belt or poly-V-belt, and the bearing comprises a wire bearing located proximal to the gantry center of mass. In this manner, the present invention provides a simple and effective technique for driving the gantry about the object, providing sufficiently accurate angular positioning in a reliable and cost effective drive system.

Abstract: A charge pump circuit comprises an input terminal for receiving an input voltage, an output terminal for providing an output voltage, and a plurality of pump stages connected in series between the input and output terminals and alternately coupled to first and second clock signals having complementary states. Each of the pump stages includes a transistor having a gate terminal, a source terminal, a drain terminal, and a bulk terminal, and a capacitor connected between the gate terminal of the transistor and a corresponding one of the clock signals. Each bulk terminal is biased by the voltage of a previous pump stage driven by the same clock signal, so that each of the corresponding threshold voltages of the transistors is suppressed to a voltage sufficient for generating a higher voltage on a low power supply voltage regardless of body effect.

Abstract: A computed tomography (CT) scanner includes an enclosure which forms a substantially sealed chamber around the rotatable disk carrying the radiation source and the radiation detectors. The CT scanner further includes an air conditioning system for controlling the temperature and humidity of the air inside the chamber. The air conditioning system can be a closed loop system whereby only air from inside the chamber is processed through the air conditioning system and no outside air is introduced to the chamber. Thus, the CT scanner can be operated in a wider range of environmental conditions. In an alternate embodiment, the air conditioning system can produce a positive pressure inside the chamber to prevent outside air from entering through openings in the enclosure. In this embodiment, the air conditioning system can include an input port in order to draw sufficient outside air to produce a positive pressure inside the chamber.

Abstract: Apparatus and methods for supplying a portion of a fluid stream and, alternately, a fluid of known composition and concentration to an analyzer are provided. The fluid stream is directed through a series of connected chambers formed in an integral housing. A sampling needle has an inlet in one of the chambers and an outlet in fluid communication with the analyzer. When desired, a tube or vial containing a known fluid may be inserted into a chamber containing the sampling needle, so that the known fluid will be supplied to the analyzer. A second needle provides ventilation to the vial to prevent the formation of a vacuum as the known fluid is drained from the vial.

Abstract: An ion generating apparatus for semiconductor fabricating equipment includes a device for reversing the orientation of a magnetic field. In this manner, the potential energy of a plurality of filaments in the ion generating apparatus are maintained at a substantially equal level, and consequently, asymmetric damage to one of the plurality of filaments due to concentration and collision of the thermal electrons is prevented, thereby prolonging the maintenance cycle of the ion generating apparatus.

Abstract: High pressure liquid chromatographic apparatus in which a fluid mixture containing at least one solute that is reactive with chromatographically reactive surfaces in the column is loaded into the column, and a number of plugs of different eluant fluids are injected into that column. The injections are made in a manner that minimizes the amount of eluant required. In one embodiment, the injections are made to insure that flow of at least the eluant fluids through the column will occur, preferably with a substantially flat wave front, at speeds corresponding to reduced velocities greater than about 5,000, i.e. at flow rates sufficient to induce turbulent flow in those fluids, thereby minimizing the time required for the entire succession of mixture and eluant fluids to traverse the column.

Abstract: A method and apparatus for performing CT scans of baggage being carried or loaded onto commercial aircraft are described. The CT baggage scanner of the invention includes numerous features which provide the system with high baggage throughput on the order of seven hundred bags per hour as well as improved image quality and accurate target detection. In one aspect, the scanner includes an adaptive image reconstruction window which identifies data collected from the field of view that are not related to the baggage being scanned. These unrelated data are excluded from the image reconstruction process, resulting in greatly reduced reconstruction time and increased baggage throughput. The invention also includes the capability of performing calibration "air scans" with objects such as the system conveyor in the field of view.

Abstract: A vapor delivery system for delivering a vapor-phase reactant to a chemical process reactor at a substantially constant flow rate. The vapor delivery system includes a source of a reactant material, means for converting the reactant material to a vapor and for maintaining a predetermined volume of vapor in a vapor phase, a flow controller for providing a controlled flow of the vapor-phase reactant to the process reactor, means for detecting a parameter related to the availability of the vapor-phase reactant material to the process reactor from the flow controller, and means responsive to the detection signal for controlling the supply of reactant material to the vapor converter. In one embodiment the parameter is the pressure of the vapor within the predetermined volume. In another embodiment the parameter is the fluid conductance of a control valve within the flow controller. The vapor delivery system of the present invention can operate in either a substantially continuous or a noncontinuous delivery mode.

Abstract: The invention disclosed is a method and apparatus for imparting a desired shape to a surface-to-be-shaped of articular cartilage in the joint of a mammal. The method discloses applying steam to a surface-to-be-shaped to soften the cartilage at and near that surface and positioning a form defining the desired shape adjacent to that softened region. A bias pressure is applied to impart the desired shape and the form is removed. An apparatus for practicing the method includes an element for generating and delivering steam to the surface-to-be-shaped to soften the surface and includes a form for molding the softened surface.

Abstract: The preparation and use of acrylic and fluoroacrylic polymers suitable for luminescence oxygen sensing applications are described. These materials can be used in luminophor coatings for optical fiber sensors or as coatings on aerodynamic surfaces for wind tunnel study. Compositions containing these polymers have the advantages of: (1) reduced induction effect; (2) subsecond response times; (3) low photodegradation; and (4) low temperature dependence.

Abstract: A load counterbalancing system with a constant load displacement force includes a load element, a position transducer and an actuator element. An environmental force acting upon the load element is counterbalanced by a support force provided by the actuator element. The environmental force is assumed to be a predetermined function of the position of the load element, and the actuator element applies the support force to the load element as defined by the predetermined function. The invention allows an operator to move the load element through its entire range of motion with a constant applied force, and to place the load element statically at any position in the range of motion.

Abstract: The invention disclosed is a method and material for repairing focal arthritic defects in a mammalian joint, especially in a human knee. The invention disclosed provides an articular cartilage cancellous bone paste in a therapeutically effective amount for enhancing formation of cartilage. The paste can include a cartilage-stimulating factor.

Abstract: A single-piece soft tissue fixation device includes an elongated element terminating in a tip at one end and a receptacle at the other end which bond with each other in a welded joint. The device is made of a heat-bondable, biocompatible material that can be ultrasonically or thermally welded. The tip and receptacle of the device can be textured or contoured or otherwise complementarily configured to promote mutual engagement prior to and during bonding. The tip can include a needle or needle-like extension for penetrating tissue. The device may be at least partially resorbable in living tissue.

Abstract: A ferroelectric random access memory device includes a plurality of reference cell array blocks implemented in a reference cell array. If the reference voltage from one of the reference cell array blocks is biased toward the voltage level of a logical data "1" or "0", another reference cell array block is chosen, which has ferroelectric capacitors of smaller or larger size than those of the selected reference cell array block. In this manner, the alternate reference cell array block provides the reference bit lines with required reference voltages. As a result, the sensing margin of the memory cells is increased, causing the reliability of the ferroelectric random access memory device to be improved.

Abstract: The invention provides an implantable apparatus which includes a power supply capable of converting non-electrical energy such as mechanical, chemical, thermal, or nuclear energy into electrical energy. The invention also provides a method of supplying energy to an electrical device within a mammalian body in which the mammal is implanted with an apparatus including a power supply capable of converting non-electrical energy into electrical energy, and non-electrical energy is transcutaneously applied to the apparatus.

Abstract: A personal inertial surveying system includes an inertial sensor and processing equipment adapted to be mounted to or carried by a person walking through a region being surveyed. As the person walks inaccuracies in position measurement due to drifts in the inertial sensor can be conveniently corrected. Corrections can be performed often during brief pauses as the person paces though the region, resulting in improved accuracy in the survey.

Abstract: A binary-weighted capacitor array is applicable for use in analog-to-digital or digital-to-analog converters, switched-capacitor filters, etc. A plurality of unit capacitors are arranged in a lateral row. The row is laid out in parallel to a switch array so that each metal interconnect between a unit capacitor and a corresponding switch is of a uniform length. This layout eliminates several limitations commonly found in capacitor arrays, including: top-plate parasitic error due to metal interconnections and metal overlap; ratio error due to oxide thickness gradients; and edge-definition errors.