A cryosurgical instrument comprises a metal cooling tip operable to be cooled by a flow of cryogenic fluid within the tip, at least a boiling region of the tip being coated with a heat-insulating coating. The presence of the heat-insulating coating can promote nucleate boiling of the fluid rather than film boiling. Nucleate boiling within the tip provides a greater cooling efficiency of the tip than film boiling.

It is known to use cryosurgical instruments in surgical operations in which living tissue is destroyed (or ablated) by cooling the tissue to well below the freezing point of water (e.g. -20.degree. to -30.degree. Centigrade).
WO 93/04647 discloses a cryosurgical instrument in which a metal tip of a cryosurgical probe is cooled by supplying liquid nitrogen to the interior of the tip.
In such an instrument, when the liquid nitrogen reaches the interior of the metal tip, it starts to boil. There are two possible modes of boiling which can take place. If so-called `film` boiling occurs, a film of nitrogen gas forms between the inner surface of the metal tip and the boiling liquid nitrogen. This film of gas reduces the heat conduction between the boiling liquid and the body of the tip and thus reduces the cooling efficiency of the instrument. The other possible mode of boiling is referred to as `nucleate` boiling. In this mode the film of gas does not form, so the heat conduction between the boiling liquid and the body of the tip is much better, and the cooling efficiency of the tip is thus improved.
Although nucleate boiling provides a more efficient cooling operation, it is often difficult to control the mode of boiling reliably so that nucleate boiling takes place. In particular, film boiling often occurs for some time at the start of a period of operation of a cryosurgical instrument. Because the cooling efficiency is lower when film boiling takes place, surgical procedures in which tissue has to be cooled can take longer. This can be both hazardous (by increasing the time during which a patient must be anaesthetized), expensive and inconvenient.


An apparatus, method, and system for automatically turning off an electrically powered actuator in a refrigeration mechanism upon detection of an unwanted condition. In one aspect of the invention, the electrically powered actuator can be the motor of an ice maker/dispenser. The detection can be accomplished by sensing the presence of an object along or near an ice dispensing pathway from the ice maker/dispenser. The unwanted condition could be the presence of the object for more than a preset time period. This would allow to distinguish between an unwanted object such as silverware or clogged ice versus a wanted object such as flowing ice cubes, crushed ice, or shaved ice.

1. Field of the Invention
The present invention relates to refrigeration mechanisms and, in particular, to such mechanisms that include electrically powered actuators.
2. Description of the Related Art
Modern refrigeration mechanisms, such as refrigerator/freezer units, have electrically powered actuators that perform a variety of functions. An example is an ice maker/dispenser. Normally, electrical motors perform functions such as operating valves to supply water to the ice maker, moving a rod or rack to eject ice that has been frozen from supplied water, and moving other structure to move, alter, or direct ice pieces to an ice delivery or dispensing chute.
In the case of an ice maker/dispenser, the user normally must manually push a button with a finger or move a glass or container against a lever to actuate the motors to dispense ice down the chute. In some models, the user can also manually push a button to select between ice cubes or crushed ice, and in some instances shaved ice. Normally, once actuated, the dispenser operates until the user releases the button or lever. In some cases, the dispenser motor continues until automatically stopped by a timer.
In either of these cases, there are situations where it may be desirable to automatically stop the dispensing motor even if the user has instructed it to continue. For example, if ice jams or clogs the ice dispensing chute, the user may continue to try to operate the dispensing motor. Ice would back up and potentially damage the system. Additionally, if a foreign object (a non-ice object) enters the chute, it would be advantageous to automatically detect the same and stop operation of the dispensing motor until the situation can be resolved.
Furthermore, maintenance is some times performed on the ice chute, or at or near the ice chute. It could be advantageous to disable the dispensing motor automatically. There are other reasons to stop moving parts, such as are obvious to those skilled in the art.
There can be other actuators in the form of motors, valves, fans, etc. that are electrically powered and may have moving parts or cause certain functions where it would be advantageous to have some sort of backup or failsafe automatic protection to disable or shut off the actuator for unwanted conditions.

Apparatus, method, and system for automatically turning off an actuator in a refrigeration device upon detection of an unwanted condition


A method and towed sonic array system for defocusing the beampattern of the towed sonic array. The method includes determining an amplitude adjustment and a phase adjustment for each of the sonic projectors; and driving each of the sonic projectors with a drive signal modified by the amplitude adjustment and the phase adjustment for that sonic projector. The amplitude adjustment and phase adjustment for each of the sonic projectors are, at least in part, based upon the distance from that sonic projector to a virtual source. The location of the virtual source may be selected so as to achieve different beampatterns, including wide-sector beams and, in at least one case, a near-omni-directional beampattern. The drive signal may include multiple frequency components, in which case the method may be used to find a set of beamformer coefficients for each of the frequency components and an inverse transform may be used to realize a defocused driving signal.

Towed linear arrays of receivers have been successfully used in marine operations for both passive and active sonar. At times, a horizontal receiver array is used with a vertical line array of projectors. At other times, the projector array may also be horizontal. In some cases, the horizontal projectors array and horizontal receiver array are linearly arranged on the same tow line. In some cases, the receiver array may be positioned aft of the projector array. In some cases, the receivers may be interspersed with the projectors, such that the arrays are intermeshed.
The natural beam pattern of a linear projector array, when driving all projectors with the same voltage signal, is a narrow focused beam perpendicular to the array, termed the "broadside beam". In order to insonify a full 360-degrees of azimuthal coverage, the control system driving the projectors tries to "sweep" the natural beam from, for example, a forward end-fire pattern through broadside to an aft end-fire pattern. The beam may be rotated through azimuth by adjusting the timing (phase) of the drive signals for the projectors. The focused nature of the beamwidth places limits on the ping repetition rate.
Similar reference numerals are used in different figures to denote similar components.

Defocusing beamformer method and system for a towed sonar array


In a method for decomposition of hydrocarbons for the production of hydrogen and carbon black, the feed stock is passed through a plasma torch, which causes a pyrolytic decomposition of the feed stock. The feed stock is transported through the plasma torch (A) in a cooled lead-in tube (1) and undergoes a first heating in an area in the immediate vicinity of the plasma flame. The material thereby produced is passed on to one or more subsequent stages where the final and complete decomposition of the hydrocarbons to carbon black and hydrogen occurs. In this area further raw material may be added which causes quenching and reacts with the already produced carbon black. An increase is thereby caused in particle size, density and amount produced without further energy supply, whereafter the products produced are expelled and separated and hot gas may be transported in a return pipe to the torch, in order to further increase the energy yield.

The traditional production methods for carbon black consist in a combustion of hydrocarbons by the supply of air. The quality achieved will be dependent on the supply of air or oxygen and the use of different amounts of oxygen in a surplus or a deficit. In the known methods substantial parts of the hydrocarbons are consumed in supplying sufficient energy for the decomposition, thus realizing a relatively low yield of carbon black. In addition to a low yield the combustion process will cause environmental pollution, since both carbon dioxides and nitrogen oxides will be produced. The waste gases from the processes will be able to be used only as fuel gas.
For the decomposition of hydrocarbons other pyrolytic methods have also been used in which plasma torches have been utilized, but it has not been possible to use these methods for continuous production due to deposits on the electrodes, which have led to stoppages in the process and expensive cleaning procedures.
Carbon which is formed by pyrolysis of hydrocarbons can be divided into two different qualities, viz. carbon black and coke (pyrolytic carbon). Carbon black is light and soft with low density and is produced in the gas phase, while coke is harder, has hign density and is produced on surfaces with relatively low temperatures, normally lower than 1100.degree. C.
From U.S. Pat. No. 4,101,639 is known a pyrolytic method for the production of carbon black where water vapour is injected into the plasma stream radially and tangentially with respect to the walls of the reaction chamber. The water vapour will avoid the formation of pyrolytic carbon and graphite in the carbon black.
The tangential stream of water vapour will protect the walls of the reaction chamber from high temperatures of the plasma stream and prevent deposition of condensed carbon on the walls. The water will however decompose and create oxygen containing groups on the carbon black surface and is this considered a disadvantage for most qualities of carbon black. Furthermore the water will decompose and create oxygen containing gases such as carbonoxides and nitrogenoxides which will pollute the off-gases in the process.
From DD 211 457 is known a method and an apparatus for the production of carbon black and hydrogen. A part of the hydrogen is recycled and is used as plasma gas. Feed stock in the form of hydrocarbons as liquid or gas is introduced radially via nozzles in one end of the reaction chamber and is mixed into a plasma stream at a temperature between 3500 K and 4000 K. The reaction chamber is equipped with tempering zones where the reaction products are quenched to a temperature of about 1100 K. The tempering zones in addition act as a heat exchanger and are used to preheat both the plasma gas and the feed stock. The disadvantage of the above method and apparatus is that the reaction chamber walls are cooled and thereby large temperature gradients arise in the reaction chamber in the area where the quenching of the feed stock occurs and uneven process condition and product qualities will be the result. In addition, deposition easily forms on cooled surfaces.

Method for decomposition of hydrocarbons


A system may include a graphics controller and a display. The graphics controller may generate video data to display on the display. The display may include a display panel for displaying the video data, a backlight unit for providing the display panel with backlight, and a display timing controller for communicating with the graphics controller over a communications path. The communications path may include a video data path for conveying video data bits, an interrupt path for conveying interrupts, and a sideband control path for conveying control signals such as a backlight enable signal for the backlight unit. The graphics controller and timing controller may perform link training operations to assess link quality between the graphics controller and timing controller. The timing controller may use interrupts to inform the graphics controller of system status. Use of the interrupts may help the system minimize the time consumed during display power-up operations.

This relates generally to displays, and more particularly, to displays with backlights.
Displays such as liquid crystal displays and other displays sometimes include backlight units. A backlight unit may include an array of light-emitting diodes or other light source for producing backlight illumination. Displays with backlight units may be incorporated into an electronic device such as a computer or cellular telephone or may be implemented as stand-alone units.
To conserve power, displays can be powered down when not in use. When it is desired to display information for a user, a display that has been powered down can be powered up and provided with video data. As part of a display power-up sequence, a graphics controller such as a video card in a computer can send a control signal to a backlight controller in an associated display that instructs the backlight controller to turn on a backlight unit for the display.
There are typically delays associated with activating backlight units in displays. If care is not taken, these delays can be obtrusive and may give rise to an appearance of sluggish display behavior.
It would therefore be desirable to be able to provide improved ways in which to power up displays that have backlights.

Display systems with handshaking for rapid backlight activation


A computer-implemented method for determining file identities may include identifying a file stream that is subject to an assessment, generating a hash based at least in part on a portion of the file stream between a start and an offset of the file stream, querying the database to determine whether the hash matches at least one file in the database, receiving a response that indicates that the file stream matches a plurality of files in the database and that requests an additional hash of the file stream that is based at least in part on an additional portion of the file stream ending between the offset and a subsequent offset of the file stream, generating the additional hash of the file stream, querying the database with the additional hash, and receiving an additional response including a characterization of the file. Various other methods, systems, and computer-readable media are also disclosed.

People increasingly rely on the Internet for business and personal use. As individuals and organizations provide more services via the Internet, there arise more opportunities for malicious parties to exploit these services to illegitimate ends. For example, malicious parties may propagate malware and other unwanted and/or illegitimate data via file transfers.
Some traditional security systems may observe the entirety of a file before making a determination. Unfortunately, retrieving and processing the entire file may be resource intensive, potentially consuming significant amounts of network bandwidth, memory, and/or other computing resources. Additionally, retrieving an entire file before making a malware determination may increase the latency of some operations that depend on a malware determination of the file. Some traditional systems may attempt to analyze a file based on a partial hash of the file. Unfortunately, some files may share significant amounts of data with other files, making positive determinations about files using partial hashes more difficult. Accordingly, the instant disclosure identifies and addresses a need for additional and improved systems and methods for determining file identities.

Systems and methods for determining file identities


An electrical connector assembly for an arcuate surface in a high temperature environment and associated method of use is disclosed for a variety of applications. This can include, but is not limited to, an injection molding heater assembly having at least one heater and an injection molding heater and nozzle assembly having at least one heater and a nozzle that is in thermal communication with the at least one heater. This at least one electrical connector, having a first electrical conductor that is electrically connectable to at least one first conductive portion on at least one arcuate surface and a second electrical conductor that is electrically connectable to at least one second conductive portion on the at least one arcuate surface, and at least one disconnect mechanism positioned adjacent to the at least one electrical connector and in electrical connection with the first electrical conductor and the second electrical conductor.

Various articles and methods of forming electrical connections are well known including soldering, spring-loaded contact pads, welding or the use of electrically conductive epoxy adhesives. However, there are problems in forming a suitably reliable electrical connection between a wire conductor and a terminal pad which is deposited on a substrate such as metal, steel, ceramic, or a substrate comprising one or more metal, steel or ceramic components or layers that are placed in high temperature environments. Unfortunately, most of these well known articles and methods for attaching a wire have an upper temperature limit beyond which the original physical characteristics become unstable so that the electrical connections so formed are incapable of reliably maintaining their attachment integrity over a wide temperature range.
For example, specialized solder is effective up to 280 degrees Celsius at which point the solder will melt and allow the wire to disconnect from the pad. In addition, the application and processing of specialized solder is time consuming. Silver epoxy is also used but silver-loaded epoxy is effective up to 250 degrees Celsius and is expensive and time consuming to process. The use of glass-loaded epoxy extends the temperature range up to 400 degrees Celsius but is also very expensive, time consuming and may contain lead or lead-based alloys. In extremely high temperature environments, spring loaded contacts mounted directly on the arcuate surface have been employed but they are very complicated, time consuming and have a limited operating life. In addition, the integrity of the spring contact reduces with age due to thermal cycling and accelerated oxidation. The integrity of a contact pad will deteriorate fast due to contact bouncing phenomenon and the soft material utilized with a pad.
Other more conventional methods of attachment such as an electric arc or flame-burner welding, narrow gap welding, plasma gap welding, plasma/laser welding, have also been employed, but these are not easily adaptable for film terminal pads on a glass loaded ceramic substrate, a ceramic-based substrate, or a coated substrate.
U.S. Pat. No. 6,039,238, issued to Panaghe, discloses a method of attaching a conductor to a thick film trace by applying pressure to a terminal lug that is affixed to the conductor and ultrasonically welding the terminal lug to the film trace. However, this method is problematic and does not address every installation scenario. For example, a means for applying this method to an arcuate (e.g., cylindrical) substrate is not addressed or contemplated. Furthermore, this method also requires the attachment of a terminal lug to the proximal end of the conductor/wire which can be expensive and problematic. Yet another shortcoming of this device is the requirement that the thick film pad be substantially the same thickness as the terminal lug. This would require either the use of a terminal lug that is very thin or a thick film pad that is very thick.
U.S. Pat. No. 5,422,457, issued to Tang et al., discloses a soldering iron with a separable plug and socket connector so that the heater can be exchanged without an accidental disconnection of the soldering assembly. However, since the temperature at the socket connector is relatively low, it does not address the issue of an electrical connection in a high temperature environment.
U.S. Pat. No. 5,352,109, issued to Benenati, discloses an injection molding apparatus that has an injection nozzle with cartridge heaters in grooves that extend axially along the outside of the nozzle. The heaters are retained in grooves by spring "C" clips. A drawback to this system is that it requires the use of liquid-filled channels or highly conductive metal rods to equalize the temperature of the nozzle from one extremity to another.
U.S. Pat. No. 6,325,615, issued to Johnson et al., discloses a wire electrical connector assembly for removably connecting two wire ends to facilitate replacement of a nozzle heater in a mold. The interconnect is located away from the heater so that it is not subject to high temperature environment. This reference does address the problem of being able to rectify a wiring failure without replacing the entire heater as well as the wiring problems that occur in the connection between the wiring and the nozzle heater in a high temperature environment.
U.S. Pat. No. 6,410,894, issued to Hoffmann et al., discloses an electric heater with a tubular substrate. There is a thick film resistive heating element that is disposed about the tubular substrate and there is a metallic overcoat that encases at least a termination portion of the heating element between the substrate and the metallic overcoat. This reference does not address the issue of removing defective wiring that is directly attached to a nozzle heater in a high temperature environment and is only marginally relevant in that it discloses axially aligned wiring.
U.S. Pat. No. 6,433,319, issued to Bullock et al., discloses a clamping mechanism for attaching a stranded conductor to a conductive coating on a substrate. It does not address the wiring problems that occur in the connection between the wiring and the arcuate substrate in a high temperature environment.
Finally, U.S. Pat. No. 6,530,776, issued to Pilavdzic et al., discloses a current method of attaching a conductor to a thick/thin film pad for a heater that is in thermal communication with an injection nozzle. There are a number of densified electrical connectors connected to a film pad with ultrasonic welding. This reference highlights the problems by showing the amount of work involved to attach the conductors to a thick pad and how difficult it would be to remove them or sever this connection without providing a suggestion regarding what to do if the heater or power supply wire fails other than the replacement of the entire heater.
Therefore, the prior art does not provide a satisfactory connector in a high temperature environment that can be readily separated from the power supply when the heater fails in order to reduce overall machine downtime and therefore, increase efficiency and uptime of the molding system. Having to physically handle the arcuate substrate can damage both the device, e.g., heater, as well as the associated wiring connected to the arcuate substrate. In the prior state of technology, the nature of the pad and the associated methods of attachment make it impossible to re-work arcuate substrate connections by any specific means. Also, it can be very time consuming to disconnect the wiring from the arcuate substrate and reconnect wiring to another arcuate substrate. This can result in significant efficiency loss and associated down time.
There is a need for a reliable connector that can facilitate replacement of the heater or power wiring to provide easy electrical attachment and disengagement of the power supply wires in a high temperature environment. The present invention is directed to overcoming one or more of the problems set forth above.

Electrical connector assembly for an arcuate surface in a high temperature environment and an associated method of use


A glue gun which includes a housing, a barrel slidably mounted in the front side of the housing, the barrel defining a heating chamber and a fusion chamber above the heating chamber, one-way clamp provided inside the housing to hold a glue stick, permitting the glue stick to be fed into the fusion chamber, a igniter and gas burner unit mounted in the housing and controlled by an ignition control switch to burn fuel gas in the heating chamber, the igniter and gas burner unit having a metal screw tube for holding a soldering tip in front of a flame nozzle thereof.

The present invention relates to a glue gun, and more particularly to a multipurpose glue gun which comprises an igniter and gas burner unit controlled to melt a glue stick for sealing. The igniter and gas burner unit has a metal screw tube for holding a soldering tip in front of a flame nozzle thereof for soldering.
A variety of glue guns have been disclosed, and have appeared on the market. These glue guns are commonly complicated and expensive. Before use, fuel gas must be filled in a gas chamber inside the housing. If storage fuel gas is used up, the gas chamber must be filled up with fuel gas again. Further, these glue guns cannot be used as a soldering gun.


A microcomputer within a duplex RF transceiver operates in an interrupt-driven manner to simultaneously encode and decode CTCSS signalling (with one microcomputer interrupt service routine being devoted to CTCSS encode, and another microcomputer interrupt service routine being devoted to CTCSS decode). Such encoding and decoding of CTCSS signalling is accomplished using minimal external control hardware (e.g., two flip flops and an inexpensive conventional multipurpose counter/timer chip). The resulting arrangement is inexpensive, reliable and requires only a few components in addition to the appropriately programmed microcomputer in order to provide simultaneous encoding and decoding of CTCSS signals in a full duplex RF transceiver context.

CTCSS (which stands for "Continuous Tone-Coded Squelch System") has long been used to provide some degree of selective calling and spurious signal rejection in two-way RF communications systems.
Two-way RF communications systems may typically include non-trunked RF repeaters that are "open" in the sense that any RF signal presented to the repeater input RF frequency will be received (and potentially retransmitted and/or regenerated) by the repeater on the repeater RF output frequency. Unless precautions are taken in such systems, it is possible for all transceiver users in the field to be disturbed by spurious transmissions (or even noise from adjacent channels or the like) on the repeater input frequency. While this situation may be acceptable for certain classes of users (e.g., amateur radio operators and other casual users), it is unacceptable for business and public service users who require a higher degree of communications privacy and reliability.
As is well known, CTCSS provides additional, subaudible analog tone signalling over voice channels in order to implement selective calling and/or selective transceiver unsquelching. Briefly, CTCSS involves dividing the audio spectrum of a standard RF channel into two portions: a subaudible "channel guard" portion (e.g., having a frequency range of about 30 Hz to slightly less than 300 Hz) speech portion (typically having a frequency range of 300 Hz to about 3 KHz or more). Speech signals received by a user transceiver via the user's microphone are band limited (typically using a 300 Hz to 3000 Hz bandpass filter) such that no significant components of the speech signal exist below 300 Hz. This lower frequency "channel guard" portion of the audio channel spectrum is reserved for CTCSS tone frequencies generated by a tone encoder included within each authorized transceiver operating on the system. When an authorized user transmits, his transceiver automatically modulates the channel guard portion of the RF envelope with one or more CTCSS subaudible tones in addition to modulating the RF envelope with the user's speech signals.
When such an authorized transmission is received by a base or repeater station, the base station demodulates the received RF signal and uses filtering techniques to separate the demodulated audio spectrum into the channel guard portion and the speech portion. The base station then detects ("decodes") CTCSS signalling with the channel guard portion of the received audio to determine whether one or more CTCSS tones are present. If the base station finds no (or only inappropriate) tones, it may simply ignore the received RF signal (thus helping to prevent unauthorized users from accessing the communications system and also preventing base station falsing on noise from adjacent channels or the like).
If the base station successfully decodes an expected CTCSS tone within the channel guard portion of a received RF signal, the base station typically regenerates a further CTCSS tone (which may be of the same or different frequency as the CTCSS tone received by the base station) and transmits this regenerated tone in the channel guard portion of a transmitted RF output signal (the received detected speech signals are simultaneously retransmitted over the speech band portion of this RF output signal).
The base station RF output signal encoded with the CTCSS signal is received by user transceivers in the field. Each user transceiver also includes a CTCSS tone decoder which controls the transceiver squelch function. While the transceiver (if activated) will typically receive all of the base stations transmissions (as well as any RF noise or other RF transmissions which may happen to be on the received frequency), only those signals encoded with appropriate CTCSS tones will cause the transceiver to unsquelch. Thus, users in the field will only hear authorized base station transmissions.
CTCSS provides a variety of different standard frequency tones (e.g., 67 Hz, 210.7 Hz, etc.), and different transceivers may be unsquelched by different tones (thus providing a limited selective calling feature in some systems). For example, the transceivers of Group A users might encode and decode a CTCSS tone of frequency X, while the transceiver of Group B users might encode and decode a CTCSS tone of frequency Y. If the base station were capable of alternately decoding and encoding tone X and tone Y, Group A base station retransmissions would only be received by the users in Group A, and Group B base station retransmissions would only be received by the users in Group B. Group privacy can thus be provided within a non-trunked repeater communications system.
Such RF communications systems as described above are typically operable in the "full duplex" mode. That is, base station can receive and transmit at the same time, and thus uses different input and output RF frequencies (and includes conventional RF filters and/or other combinet arrangements) so as to permit simultaneous RF transmission and reception. This full duplex capability poses an additional constraint not present in simplex or half-duplex RF communications systems, however, and generally prevents significant sharing of components between transmit-related and receive-related signal processing circuitry.
For example, full duplex RF transceivers must include separate audio amplifier stages for processing received audio signals and transmit audio signals, separate local oscillator components for producing transmit and receive local oscillator frequencies, etc. (as opposed to half-duplex type transceivers which may share and multiplex such components between receive and transmit modes). Of course, even in such full duplex RF communications systems, typical user transceivers are usually only "half duplex" (i.e., transmitting and receiving on different RF frequencies, but incapable of transmitting and receiving simultaneously) in order to decrease cost by permitting circuit sharing between transmit and receive functions.
As one example of such half-duplex arrangements, prior art GE DELTA and RANGR II lines of mobile transceivers include microprocessor-controlled, digitally programmable CTCSS tone encode and decode features. See, for example, the following prior GE publications:
Maintenance Manual 136-174 MHz Synthesizer/ Interconnect Board 19D900961G13,15 Wideband, LBI317733A, 1990; PA1 GE Mobile Comm., MASTR II, Station Programmable Channel Guard (Encode Only) 19C331044G1, Maintenance Manual, 1982; PA1 GE Mobile Comm., MASTR II, Programmable Channel Guard 19D432500G1-3, Maintenance Manual, 1981; and PA1 Mobile Radio, Instructions for Multi-Tone Channel Guard Encoder 19D423094G1 Options 9564-9570, General Electric, 1976. PA1 U.S. Pat. No. 4,376,310 Stackhouse Mar. 8, 1983; PA1 U.S. Pat. No. 4,484,355 Henke et al Nov. 20, 1984; PA1 U.S. Pat. No. 4,171,516 Challen et al Oct. 16, 1979; PA1 U.S. Pat. No. 4,654,881 Dolikian et al Mar. 31, 1987; PA1 U.S. Pat. No. 4,627,098 Dolikian et al Dec. 02, 1986; PA1 U.S. Pat. No. 4,455,617 Dolikian Jun. 19, 1984; PA1 U.S. Pat. No. 4,554,542 Dolikian Nov. 19, 1985; and PA1 U.S. Pat. No. 4,463,221 Soulliard et al Jul. 31, 1984.
However, since these transceivers are only "half duplex" (i.e., they alternately transmit and receive), they do not need to simultaneously encode and decode CTCSS signalling. During transmit, the microprocessor within such prior art transceivers generates CTCSS signalling under software control; and during receive, the microprocessor decodes CTCSS signalling under software control (in each case, the specific CTCSS signalling frequency may be specified by data stored in a personality PROM within the transceiver).
As will be explained, however, such prior art arrangements cannot be readily adapted for full duplex systems. Thus, in the past it has been necessary to provide separate hardware circuits in full duplex type systems where simultaneous encoding and decoding of CTCSS tones is required.
In fact, it was not so long ago that it was necessary to provide a separate hardware component or module for each different CTCSS frequency tone to be decoded by a full duplex base station; and a further separate RF component or module for each different CTCSS frequency tone to be encoded by the base station. Such hardware-based CTCSS tone encoding and tone decoding components were generally not programmable or otherwise easily alterable for different CTCSS tone frequencies and (although perhaps in some cases similar to one another structurally) had to be customized via some physical process (e.g., manual tuning of an oscillator, installation of an appropriate mechanical filter, etc.) in order to operate on a particular desired CTCSS frequency.
Digital technology (e.g., digital signal processors, microprocessors, digitally programmable tone synthesizers, and digital filtering techniques) has made such frequency-specific hardware components largely obsolete. State-of-the-art CTCSS tone encoding and decoding is now typically performed with software-programmable, digitally-responsive encoders and decoders. The following is a non-exhaustive (but somewhat representative) listing of prior-issued U.S. patents relating to digital tone encoding/decoding (some specific to CTCSS):
The Henke et al patent relates to CTCSS tone detectors and generators controlled by a digital data controller. In this Henke et al arrangement, a tone frequency synthesizer and a digitally programmable filtering network external to a data controller are used to programmably encode and decode CTCSS tones in response to digital signals provided by the data controller. The data controller, in turn, selects the particular CTCSS tone frequencies for encoding and decoding in response to information stored in a PROM (programmable read only memory).
The Dollklan et al arrangements disclosed in the '098 and '881 patents cited above relate to channel guard tone signalling over a wire line. These patents disclose a Motorola MC6803-1 microprocessor type digital controller connected with an external digital tone decoder and an external digital code encoder (see FIG. 4). The microprocessor writes to the digital tone decoder a digital data word selecting a particular tone to decode, and writes to the digital tone encoder a particular data word selecting a tone to be generated. Since the digital tone decoder and digital tone encoder are dedicated to decoding and encoding tones, respectively (and are also external of the microprocessor), they are capable of operating simultaneously such that tones can be simultaneously encoded and decoded.
As mentioned above in connection with GE's prior DELTA and RANGR II MASTR mobile transceivers, relatively inexpensive microprocessors are now fast enough (and otherwise capable) of performing tone encoding and/or tone decoding internally under software control. Digital filtering techniques are commonly used to implement multi-pole filters capable of distinguishing between different tone frequencies. Similarly, it is known how to program a microprocessor to synthesize tones at selected frequencies. Given the spare processing capacity available in RF transceiver control microprocessors --and given the additional flexibility provided when tone encoding and/or decoding functions are performed under software control--it has become desirable in modern RF transceivers to perform all tone encoding and decoding functions with the transceiver microprocessor under software control.
General Electric's DELTA and RANGR II lines of RF transceivers mentioned above are capable of generating CTCSS tones entirely under software control using the transceiver microprocessor, and are also capable of decoding CTCSS tones with the microprocessor under software control. Such transceivers use now-conventional software algorithms (e.g., three-dimensional vector type decode analysis) for reliably, accurately detecting and decoding CTCSS tones of specific frequencies and for encoding (generating) CTCSS tones for transmission. As mentioned, such transceivers operate in only a half-duplex mode and are otherwise not capable of encoding and decoding CTCSS tones simultaneously.
In fact, the basic limitation that a microprocessor is incapable of truly concurrent instruction processing (i.e., it can only process one instruction at a time) leads to a significant problem when attempting to use a single processor for simultaneous CTCSS tone encoding and decoding within a full duplex RF transceiver. A single conventional microprocessor is simply not capable of simultaneously (a) executing an instruction causing a CTCSS tone to be decoded, and (b) executing another instruction causing a CTCSS tone to be encoded. Because received and transmitted CTCSS tones may vary in phase and other timing parameters relative to one another, it may sometimes be that an event relating to CTCSS tone encoding occurs at nearly the same instant in time as an event relating to CTCSS tone decoding in a full duplex environment. A single microprocessor is (because of its inherent incapability of processing instructions in a truly concurrent or parallel manner) incapable of handling such nearly simultaneous events.
For these and other reasons, full software-controlled tone encoding and tone decoding in a single processor architecture without significant tone generation and/or detection circuitry external of the processor has in the past been successful only in contexts where simultaneous tone reception and tone generation is not required. In other contexts (such as full duplex RF transmission systems employing CTCSS signalling) in which simultaneous tone encoding and decoding is required, hardware dedicated to tone encoding and/or decoding has been required in the past--with a microprocessor often supervising the hardware via generating digital control signals but not itself both generating and decoding tones while providing such external hardware components permits simultaneous tone encoding and tone decoding, it also increases the cost and complexity of the RF transceiver. It would be highly desirable to provide a full duplex RF transceiver digital CTCSS tone encoding and decoding arrangement capable of simultaneously encoding and decoding CTCSS tones under software control using a single processor in conjunction with minimal and inexpensive external hardware components.
The present invention provides such a full duplex RF transceiver arrangement including microprocessor that executes CTCSS tone encoding software as well as CTCSS tone decoding software. Simultaneous CTCSS tone encoding and decoding is provided--even though only a single processor is used to perform both functions. In the preferred embodiment, an external memory element (e.g., a flip flop) is used by the processor to help detect transitions of received CTCSS tone signals to be decoded. This memory element (and an associated timing circuit) augments the processor functionality such so that simultaneous software-controlled CTCSS tone encode and decode can be cost-effectively provided in a full duplex RF transceiver using only minimal CTCSS-related encode and decode hardware components external to the processor.

Full duplex RF repeater/base station providing microprocessor-controlled simultaneous CTCSS tone encode/decode


An optical waveguide includes a porous substrate having pores of first width, a barrier layer having apertures aligned with the pore openings, and a core material layer adjacent the barrier layer. The apertures have a second width less than the first width.

Photonic crystals (PCs) are a class of structure engineered materials that prohibit propagation of light modes of certain frequencies. Photonic crystal waveguides (PCWGs) are linear defects made in PCs that can propagate photonic modes at frequencies prohibited in bulk PCs. As a result, the electromagnetic field is tightly confined within the waveguides cross-section. This enables sharp bends and low-loss sharp splitters with low mode volumes inaccessible for conventional waveguides. PCWGs may also be engineered for a particular dispersion (e.g., a very low group velocity, a negative group velocity, or a rapidly changing group velocity.) These properties may be useful for the development of electro-optical integrated circuits.
A common type of PCWG is a quasi two-dimensional waveguide. A quasi two-dimensional waveguide is fabricated in a slab of optically transparent material and has essentially two dimensional patterns. Such structures are relatively easy to fabricate, however, light can be lost into the cladding above and below the waveguide. In the third dimension, the light is essentially index guided. Therefore, the index of refraction in both claddings should be as low as possible. The top cladding may be air with an index of refraction equal to one, which sets an upper limit for the parameter space available for designing low loss waveguides. If, however, the bottom cladding has an index of refraction greater than one, the parameter space will be limited by this index of refraction.
For these and other reasons, there is a need for the present invention.


The invention relates to a radio apparatus for estimating a direction from which a received wave arrives and forming a radio transmission channel between a transmitting end of the received wave and itself. The invention aims to maintain stable transmission quality. The radio apparatus of the invention includes: two receiving sections which alternately detect two received waves that have arrived from a same transmitting end to two elements, in every period as an integer multiple of a period of each symbol of the received waves; and an arriving angle calculating section which calculates, in every period, an arriving angle as an inverse function of a difference in two phases which are proportional to a distance between the two elements, given as a function of positions of the elements and the arriving angle of the received waves, and contain a difference in phase shift amounts of the two receiving sections.

1. Field of the Invention
The present invention relates to a radio apparatus for estimating the direction from which a received wave arrives at an antenna and forming a radio transmission channel against a transmitting end of the received wave through the antenna.
2. Description of the Related Art
In recent years, many electronic units are provided with a digital signal processor that performs digital signal processes for many signals in the base band region at high speed, in real time, and at low cost have been outspread.
Thus, for example a radio base station of a mobile communication system that corresponds to the CDMA system actively uses such digital signal processes for not only keeping the directivity of each of a plurality of channels that are formed in parallel by an array antenna composed of a plurality of elements, but also removing interference caused by the directivity and improving the transmission quality of digital signals.
FIG. 8 is a block diagram showing an example of the structure of a radio base station's apparatus that has an array antenna. In the drawing, feeder ends of a plurality of N elements 90E-1 to 90E-N disposed at constant intervals on a virtual straight line are connected to their first input terminals of splitters 91-1 to 91-N, respectively. Output terminals of the splitters 91-1 to 91-N are connected to corresponding input terminals of an arriving angle estimating portion 93 and a beam forming portion 94-R through receiving portions 92-1 to 92-N, respectively. An output terminal of the beam forming portion 94-R is connected to an input terminal of a demodulating portion (not shown). An output terminal of the arriving angle estimating portion 93 is connected to a control input terminal of the beam forming portion 94-R and a control input terminal of a beam forming portion 94-T paired with the beam forming portion 94-R. An input terminal of the beam forming portion 94-T is connected to an output terminal of a modulating portion (not shown). A plurality of N output terminals of the beam forming portion 94-T are connected to first input terminals of signal combing portions 95-1 to 95-N. A single or a plurality of base band signals that will be described later are supplied in parallel to second to p-th (where p≧2) input terminals of each of the signal combining portions 95-1 to 95-N. Output terminals of the signal combining portions 95-1 to 95-N are connected to the other (second) input terminals of the splitters 91-1 to 91-N through transmitting portions 96-1 to 96-N, respectively.
Suffixes of the plurality of elements 90E-1 to 90E-N, splitters 91-1 to 91-N, and receiving portions 92-1 to 92-N are used in common throughout the following description. A combination of an element, a splitter, and a receiving portion that are cascade connected is referred to as a branch.
In the following description, a mutual arrangement of these branches is represented by a physical arrangement of the elements 90E-1 to 90E-N disposed on the foregoing virtual straight line.
In the apparatus of the radio base station, the receiving portions 92-1 to 92-N heterodyne detect (or homodyne detect) received waves that have arrived in parallel at the elements 90E-1 to 90E-N and then input through the splitters 91-1 to 91-N, respectively. As a result, the receiving portions 92-1 to 92-N generate N base band signals S1 to SN, respectively.
In this example, for simplicity, it is assumed that the amplitudes of the base band signals S1 to SN are a common value ("1" normalized by its nominal value). In addition, it is also assumed that the wavelengths of the received waves are a known value λ.
The arriving angle estimating portion 93 performs the following arithmetic operations expressed by the following formulas (1) to (4) to obtain the average value Θ of phase differences of the base band signals S1 to SN obtained through the branches adjacently disposed at constant intervals.
                              S          k                =                                            ⅇ                                                j                  θ                                                k                                                                (                              k                =                                  1                                                                                to                                                                                N                                            )                                                                                (        1        )                                          ϕ                      k            ,                          k              +              1                                      =                  Arg                                (                                          S                                  k                  +                  1                                            ·                              S                k                *                                      )                                              (        2        )                                          θ                      k            ,                          k              +              1                                      =                              sin                          -              1                                                      (                                                            ϕ                                      k                    ,                                          k                      +                      1                                                                      ·                                  λ                  /                  2                                                          π                                                                                d                        )                                              (        3        )                                Θ        =                              {                          1              /                              (                                  N                  -                  1                                )                                      }                    ·                                    ∑                              k                =                1                                            N                -                1                                                                θ                              k                ,                                  k                  +                  1                                                                                (        4        )
In addition, the arriving angle estimating portion 93 obtains an arriving angle ΘA of the received waves as an azimuth angle that is uniquely defined by the average value Θ and the arrangement of the elements 90E-1 to 90E-N (including an azimuth represented by the foregoing virtual straight line).
The beam forming portion 94-R supplies to the demodulating portion a signal obtained as the sum of products of weights ejψ1 to ejψN that represent phase shift amounts ψ1 to ψN against a main lobe of the array antenna 90 in the direction of the arriving angle ΘA and the base band signals S1 to Sn (the resultant signal is hereinafter referred to as base band signal R) so as to form a beam in the base band region.
On the other hand, the beam forming portion 94-T performs the reverse process of the process that the beam forming portion 94-R performs for the base band signal T supplied from the modulating portion. As a result, the beam forming portion 94-T generates N base band signals.
The signal combining portions 95-1 to 95-N combine these N base band signals and sets each of which is composed of a single or a plurality of base band signals, that correspond to the N branches, and that are modulated with transmission information to be transmitted to individual terminals (users) other than the transmitting end of the received wave is transmitted.
The transmitting portions 96-1 to 96-N convert N transmission base band signals into desired radio frequency signals and transmit them in parallel through the splitters 91-1 to 91-N and the elements 90E-1 to 90E-N, respectively.
In other words, since a full duplex radio transmission channel is formed against the transmitting end of the received wave that arrives at the array antenna 90 by the formed beam with a desired directivity, the transmission quality is kept high.
Patent Document 1
Japanese Unexamined Patent Application Publication No. 2002-107439
Patent Document 2
Japanese Unexamined Patent Application Publication No. HEI 10-170621
Patent Document 3
Japanese Unexamined Patent Application Publication No. HEI 6-273504
Patent Document 4
Japanese Unexamined Patent Application Publication No. HEI 8-114662
However, in the foregoing related art references, the accuracy of the arriving angle obtained by the arriving angle estimating portion 93 is sufficiently kept high when the deviations of the phase shift amounts and gains of the receiving portions 92-1 to 92-N are small.
However, the receiving portions 92-1 to 92-N have circuits and devices such as a low noise amplifier (LNA) and a frequency converter whose natural characteristics are nonlinear and involve deviations and whose phase shift amounts and gains may be subject to largely change corresponding to temperature, other environmental conditions, and aged deterioration of the apparatus.
In other words, the arriving angle obtained by the arriving angle estimating portion 93 involves an error and a change. The error and change may cause the transmission quality and the service quality to deteriorate.
These problems would be solved if the receiving portions were designed, produced, set, and kept so that the deviations of the characteristics are very small. Such countermeasures have not been taken because of high cost.
As a related art reference for solving the foregoing problems, there is a patent application filed by the applicant of the present patent application as Japanese Patent Application No. 2001-533594, titled Deviation Compensating Apparatus (translated title).
However, the deviation compensating apparatus needs to have as feed forward circuits dedicated branching circuits, combining circuits, receivers, and so forth. Thus, as the number of elements of an array antenna becomes larger, there is a possibility of which the scale of the hardware increases.


A method and apparatus for recovering data by a digital audio interface begins by receiving a stream of biphase encoded data. The processing continues by determining whether a next transition of a frame of the plurality of frames occurs during a first, second, or third time window after a preceding transition of the frame. When the next transition occurs during the second predetermined time, the digital audio interface synchronizes to a data rate of the stream of biphase encoded data based on the next transition and the preceding transition. If, the next transition occurs during the first or third predetermined windows, the digital audio interface synchronizes to a data rate of the stream of biphase encoded data based on the preceding transition edge and a subsequent transition. When the transition occurs during the third time window, the biphase encoding is violated, which indicates that a preamble is being received.

As is known, a compact disc (CD) stores digital audio data that is read by a CD player. The CD player, which may be a standalone device, such as a portable compact disc player, part of an audio system, or contained within a personal computer, renders the digital audio data into audible signals. To ensure that a CD player can play various CDs, standards have been established to prescribe the digital encoding and data rates of audio signals.
One such standard, AES3-1992,—established by the audio engineering society (AES)—provides guidelines for transmitting digital audio data over a single transmission line. In general, digital audio is serially communicated over a single transmission line in data blocks. Each data block is comprised of a plurality of frames (for example, 192). Each frame, in turn, is comprised of two preambles, two data channels, control information, and error detection information. The preambles delineate the two data channels within a frame, where the first preamble of a first frame of new block is unique to identify the beginning of the new block. The AES3-1992 further prescribes that the digital audio data is to be biphase encoded, with the preambles being violations of the biphase encoding.
The digital audio data may be transmitted at a data rate of 32 kHz, 44.1 kHz, 48 kHz, or 96 kHz, depending on the audio application. For example, digital video discs (DVD), which digitize audio in accordance with Dolby AC-3 technologies, use a 96 kHz data rate. In addition, the system clock a digital audio interface may be 256, 384, or 512 times the sampling frequency, which is selectable via control data. As such, an AES3-1992 compliant transmitter and/or receiver must be able to process digital audio at any of the data rates and using any of the selectable clock frequencies.
Therefore, a need exists for a method and apparatus for interfacing digital audio in accordance with the AES3-1992 standard.


A phased array balloon antenna having an inner membrane coupled to an outer membrane and a phased array antenna connected to an inner membrane. The phased array antenna transmits an energy towards a reflective film on the outer membrane, reflecting the energy outwards and illuminating an area smaller than that illuminated by the phased array alone.

Large aperture antennas are needed in satellite based radars to focus a radar beam, due to the limitations on power available on the satellite. In order to place a large aperture antenna in space on a satellite the radar assembly has to be packaged to fit into the launch rocket as well as be assembled or unfolded in space. This is very difficult and prohibitive for large aperture phased arrays.
Phased array radar systems are preferred in space based applications due to the ability to electronically steer the array, thereby not requiring a movement of mass. Making a large phased array antenna that can be assembled or unfolded in space is very difficult task. There is a need to provide the effect and coverage of a large aperture phased array antenna while solving the problems of difficulty of installation in space and limited power supply.

The United States of America as represented by the Secretary of the Navy


An x-ray-based cement evaluation tool for determining whether a cement bond exists between the casing and cement of a cemented borehole is provided, the tool including at least: an internal length comprising a sonde section, wherein said sonde section further comprises an x-ray source; a radiation shield for radiation measuring detectors; arrayed pixelated detectors; sonde-dependent electronics; and a plurality of tool logic electronics and PSUs. A method of using an x-ray-based cement evaluation tool for measuring a cement bond between a casing and the cement of a cemented borehole is also provided, the method including: producing x-ray in a conical beam to illuminate a well casing; measurement of the returning photons as a function of radial and axial offset; remapping the intensity of returning photons to a geometric response within the casing and cement; and determining whether an annulus is present between the casing and cement.

Within the oil & gas industry, the requirement to gauge the quality of cement through well casing is paramount as is the ability to determine the status of the annuli. The industry currently employs various methods for the verification of the hydraulic seal behind a single casing string. Typically, ultra-sonic tools are run within the well to determine whether cement is bonded to the outside of the casing, thereby indicating the presence of cement in the annulus between the casing and formation, or between the casing and an outer casing. Ultimately, a leak-off (pressure) test is required to ensure that zonal isolation has been achieved as Ultrasonic tools are highly dependent upon quality of the casing, the bond between the casing and the material in the annulus, and the mechanical properties of the material in the annulus to be able to work correctly. In addition, ultrasonic tools treat the material in the annulus as a single isotropic and homogenous volume, any actual deviation away from this ideal leads to inaccuracies in the measurement.
Typically, a micro-annulus is defined as being a gap between the casing and cement of 30 micrometers or more (i.e. 0.03 mm)
Current tools can offer information regarding the cement bond of the inner-most casing, yet do not have the ability to discriminate various depths into the cement or annular material. This can lead to the possibility that fluid-migration paths may exist at the cement-formation boundary, within the cement itself, or between the casing and an outer casing, thereby leading to a loss of zonal isolation.
Further, x-ray-based techniques that are designed to produce a three dimensional voxelated map of the cement in the cement annuli but are unable to determine whether a micro-annulus exists. Typically, acoustic/ultra-sound tools need to be run within the same tool-string as the x-ray tool, such that the acoustic/ultra-sound tools inspect the cement bond, and x-ray tools inspect the cement mass.
No viable x-ray technologies are currently available which are able to determine whether a delamination or micro-annulus exists.
Prior art teaches a variety of techniques that use x-rays or other radiant energy to inspect or obtain information about the structures within or surrounding the borehole of a water, oil or gas well, yet none teach of a method or means to compare the anticipated density profile around the casing-cement interface to the measured interface profile.
US20180180765 to Teague et al teaches of a method and means to use a pseudo-conical x-ray beam, located within a non-padded concentrically-located borehole logging tool, for the purpose of detecting density variations within the annular materials surrounding a borehole within single or multi-string cased-hole environments. The arrangement of the collimated detectors permits the collection of data that relates specifically to known azimuthal and radially located regions of interaction (azimuthally distributed depths of investigation).
US20180188411 to Teague et al teaches of a method and means to use employ an actuated combination of collimators, located cylindrically around an X-ray source, located within a non-padded concentrically-located borehole logging tool, for the purpose of detecting density variations within the annular materials surrounding a borehole within single or multi-string cased-hole environments. It also teaches of the capability to actuate collimators, switching between a fixed collimator mode, that provides the output of an azimuthal array of a plurality of x-ray beams (from said x-ray source), or to select through actuation, a mode that produces a single or plurality of individual azimuthally arranged x-ray beams that 'scan' azimuthally, through the rotation of one of the collimators. In addition, it teaches of the opportunity to select a mode that permits the selection of a non-rotating mode but actuates a collimated sleeve the switches between various angles or declinations of x-ray beam outputs (compared to the major axis of the tool).
U.S. Pat. No. 7,675,029 to Teague et al teaches concepts for an apparatus that permits the measurement of x-ray backscattered photons from any horizontal surface inside of a borehole that refers to two-dimensional imaging techniques.
U.S. Pat. No. 8,481,919 to Teague teaches of a method of producing Compton-spectrum radiation in a borehole without the use of radioactive isotopes, and further describes rotating collimators around a fixed source installed internally to the apparatus but does not have solid-state detectors with collimators. It further teaches of the use of conical and radially symmetrical anode arrangements to permit the production of panoramic x-ray radiation.
U.S. Pat. No. 7,705,294 to Teague teaches a concept for an apparatus that aims to measure backscattered x-rays from the inner layers of a borehole in selected radial directions with the missing segment data being populated through movement of the apparatus through the borehole. The apparatus permits generation of data for a two-dimensional reconstruction of the well or borehole, but the publication does not teach of the necessary geometry for the illuminating x-ray beam to permit discrimination of the depth from which the backscattered photons originated, only their direction.
U.S. Pat. No. 3,564,251 to Youmans discloses of the use of a azimuthally scanning collimated x-ray beam that is used to produce an attenuated signal at a detector for the purposes of producing a spiral-formed log of the inside of a casing or borehole surface immediately surrounding the tool, effectively embodied as an x-ray caliper.
U.S. Pat. No. 7,634,059 to Wraight discloses a concept and apparatus that may be used to measure two-dimensional x-ray images of the inner surface inside of a borehole without the technical possibility to look inside of the borehole in a radial direction.
US2013/0009049 to Smaardyk discloses the concept for an apparatus that allows measurement of backscattered x-rays from the inner layers of a borehole.
U.S. Pat. No. 8,138,471 to Shedlock discloses a concept for a scanning-beam apparatus based on an x-ray source, a rotatable x-ray beam collimator and solid-state radiation detectors enabling the imaging of only the inner surfaces of borehole casings and pipelines.
U.S. Pat. No. 5,326,970 to Bayless discloses a concept for a tool that aims to measure backscattered x-rays from inner surfaces of a borehole casing with the x-ray source being based on a linear accelerator.
U.S. Pat. No. 5,081,611 to Hornby discloses a method of back projection to determine acoustic physical parameters of the earth formation longitudinally along the borehole using a single ultrasonic transducer and a number of receivers, which are distributed along the primary axis of the tool.
U.S. Pat. No. 6,725,161 to Hillis discloses of a method of placing a transmitter in a borehole, and a receiver on the surface of the earth, or a receiver in a borehole and a transmitter on the surface of the earth, with the aim to determine structural information regarding the geological materials between the transmitter and receiver.
U.S. Pat. No. 6,876,721 to Siddiqui discloses a method to correlate information taken from a core-sample with information from a borehole density log. The core-sample information is derived from a CT scan of the core-sample, whereby the x-ray source and detectors are located on the outside of the sample, and thereby configured as an outside-looking-in arrangement. Various kinds of information from the CT scan such as its bulk density is compared to and correlated with the log information.
U.S. Pat. No. 4,464,569 to Flaum discloses a method to determine the elemental composition of earth formations surrounding a well borehole by processing the detected neutron capture gamma radiation emanating from the earth formation after neutron irradiation of the earth formation by a neutron spectroscopy logging tool.
U.S. Pat. No. 4,433,240 Seeman to discloses a borehole logging tool that detects natural radiation from the rock of the formation and logs said information so that it may be represented in an intensity versus depth plot format.
U.S. Pat. No. 3,976,879 to Turcotte discloses a borehole logging tool that detects and records the backscattered radiation from the formation surrounding the borehole by means of a pulsed electromagnetic energy or photon source, so that characteristic information may be represented in an intensity versus depth plot format.
U.S. Pat. No. 8,664,587 to Evans et al discloses a method and means for creating azimuthal neutron porosity images in a logging while drilling environment. As bottom hole assembly based systems historically relied upon the rotation of the drill string to assist in the acquisition of azimuthally dependent data, the patent discusses an arrangement of azimuthally static detectors which could be implemented in a modern BHA which does not necessarily rotate with the bit, by subdividing the neutron detectors into a plurality of azimuthally arranged detectors which are shielded within a moderator to infer directionality to incident neutrons and gamma.
U.S. Pat. No. 9,012,836 to Wilson et al discloses a method and means for creating azimuthal neutron porosity images in a wireline environment. In much similarity to U.S. Pat. No. 8,664,587 the patent discusses an arrangement of azimuthally static detectors which could be implemented in a wireline tool to assist an operator in interpreting logs post-fracking, by subdividing the neutron detectors into a plurality of azimuthally arranged detectors which are shielded within a moderator to infer directionality to incident neutrons and gamma.
U.S. Pat. No. 4,883,956 to Manente et al discloses an apparatus and methods for investigation of subsurface earth formations, using an apparatus adapted for movement through a borehole. Depending upon the formation characteristic or characteristics to be measured, the apparatus may include a natural or artificial radiation source for irradiating the formations with penetrating radiation such as gamma rays, x-rays or neutrons. The light produced by a scintillator in response to detected radiation is used to generate a signal representative of at least one characteristic of the radiation and this signal is recorded.
U.S. Pat. No. 6,078,867 to Plumb discloses a method for generating a three-dimensional graphical representation of a borehole, comprising the steps of: receiving caliper data relating to the borehole, generating a three-dimensional wire mesh model of the borehole from the caliper data, and color mapping the three-dimensional wire mesh model from the caliper data based on either borehole form, rugosity and/or lithology.
U.S. Pat. No. 3,321,627 to Tittle discloses of a method, and means of practice of a system of collimated detectors and collimated gamma-ray sources to determine the density of a formation outside of a borehole, to be represented in a density versus depth plot format. However, fails to teach of a means or method to achieve such through the steel wall of a single or multiple well casings.

Methods and means for determining the existence of cement debonding within a cased borehole using x-ray techniques


An active implantable medical device having a plurality of connection terminals able to be connected to electrodes placed in at least three distinct respective sites in a myocardium; circuits for measuring an intracardiac bio-impedance, comprising circuits for injecting a current and circuits for collecting a voltage at respective poles of a configuration of said connection terminals, and circuits able to deliver at an output a dynamic impedance signal that is a function of the injected current and the collected voltage; and circuits for evaluating an intracardiac volume, receiving at in input the impedance signal and delivering at an output a dynamic value of volume representing an instantaneous absolute value of intracardiac volume.

Intracardiac bio-impedance is a parameter correlated with cardiac flow, and thus with the ejection fraction, which are parameters that can be useful in controlling certain stimulation parameters such as heart rate and/or atrio-ventricular delay in a direction making it possible to maximize flow, or in controlling inter-ventricular delay in the case of a biventricular stimulation.
EP-A-1116497 and its counterpart U.S. Pat. No. 6,604,002 (which U.S. patent is incorporated herein by reference), both assigned herewith to ELA Médical, Montrouge, France, describe a dynamic measurement of intracardiac trans-valvular bio-impedance (i.e., between an atrium and a ventricle located on the same side of the heart). EP-A-1138346 and its counterpart U.S. Pat. No. 6,725,091 (which U.S. patent is incorporated herein by reference), both assigned herewith to ELA Médical, Montrouge, France, describe measurement of a trans-septum bio-impedance (i.e., between a site located on one side of the heart and a site located on other side of the heart), such configuration capable of being an oblique trans-septum configuration (i.e., between a ventricle on one side of the heart and an atrium located on the opposite side) or an interventricular trans-septum configuration (i.e., between the two ventricles).
The intracardiac bio-impedance is measured by injection of a current and collection of a voltage at respective poles in a tripolar or quadripolar configuration of electrodes placed inside the myocardium (atrial electrode, ventricular proximal electrode, ventricular distal electrode, etc). The bio-impedance, no matter how it is measured, is a dynamic parameter (i.e., it varies continuously during the same cardiac cycle) giving an indication of the instantaneous cardiac flow. More precisely, variations of intracardiac bio-impedance depend mainly on variations of the volume of the cardiac cavities, a low impedance corresponding to a high volume, and a high impedance corresponding to a low volume. The impedance thus varies between a minimum, reached at the end of the diastolic phase, and a maximum, reached at the end of the systolic phase. The difference between the systolic impedance and the diastolic impedance gives a value correlated to the ejection volume, a value from which one can evaluate the cardiac flow, which is the product of the ejection volume multiplied by the heart rate. The indications provided by these measurements are relative indications of the systolic and diastolic volumes, i.e., one determines the difference between these volumes, which, with the knowledge of the rate, is sufficient if one only wishes to evaluate the cardiac flow. On the other hand, these devices do not give access to an absolute measurement of intracardiac volume.
The starting point of the present invention is the observation that, in certain circumstances, it may be useful for diagnostic purposes to have a signal representing an absolute measurement of intracardiac volume. Until now, the absolute value of intracardiac volume has been estimated starting from echographic signals, which make it possible to evaluate the diastolic volume and the systolic volume, i.e., the two extreme values of intracardiac volume, and gives an indication of the way in which volume varies between these two extremes during the same cycle. However, this technique is applicable only when the patient undergoes an examination, which does not allow a permanent follow-up, over the long term. Further, the values obtained are computed values, which are posted or printed by the echographic device but do not constitute signals that could, for example, allow controlling of a function of a pacemaker or a diagnosis of certain pathologies by analysis of evolution of this signal.

Active implantable medical device including means for the evaluation of intracardiac volume


A spring assembly includes a spring seat clamped to a leaf spring at a center portion. The spring seat includes a cutout for distributing clamping stresses in a substantially uniform manner across the leaf spring. The cutout provides a relief for a central portion of the leaf spring to uniformly distribute clamping pressures across the leaf spring. Uniformly distributing stresses across the width of the spring increases leaf spring fatigue life.

This invention generally relates to a leaf spring assembly and specifically to a method of relieving leaf spring mounting stresses.
Conventional leaf springs for vehicle suspensions comprise flat rolled steel strips having a substantially rectangular cross-sectional shape along a plane perpendicular to the longitudinal direction of each steel strip. The leaf spring assembly includes a clamped center portion for mounting of an axle and a suspension member. The suspension member is typically a coil or air spring to further absorb road inconsistencies. The highest stresses on the leaf spring are experienced in the clamped section of the leaf spring. Many stress relieving techniques and methods have been used in conventional leaf spring assemblies in order to reduce negative affects that high stress concentrations produce.
One conventional leaf spring assembly includes a short spring seat member and a single long leaf spring member. The long leaf spring member extends from a first mount to a second mount. The spring seat member extends to a central clamp securing the spring seat to the longer leaf spring. The axle or other suspension member is fastened at the center clamp. The highest stress within the long leaf spring occurs at the center clamp. The stress concentration at the center clamp is non-uniform across the leaf spring. The increased and non-uniform stress concentration typically results in reduced spring fatigue life.
Accordingly, it is desirable to develop a leaf spring assembly including stress-relieving features to uniformly distribute stresses and increase the overall fatigue life of the leaf spring assembly.

Method for relieving spring seat mounting stresses


Presented herein is a unique portable electronic hand-held label dispenser that is adjustable to accommodate labels of various widths by lengthening the pins and replacing a lower guide plate, and which additionally incorporates a sensor mechanism that precisely determines the length of each label, in order to accurately advance the roll of labels according to the captured data and dispense a single label at a time, and which includes the added advantage of a unique slotted uptake wheel that efficiently collects the paper backing for easy disposal. Depressing an electronic switch causes a label to be dispensed and also activates the sensor mechanism, which allows a roll of labels to advance until the end of the next label is identified, indicating that the roll has been advanced the full length of a single label, and additionally the uptake wheel rotates to capture the discarded paper backing.

1. Field of Invention
This invention relates generally to hand-held label dispensing devices, and specifically to such devices that accommodate a plurality of label sizes.
2. Description of the Related Art
Hand-held devices for dispensing and applying labels are well known in merchandising and warehousing industries for labeling, applying identification labels, pricing, and other uses. These devices, referred to as labelers, commonly involve a method to automatically advance and dispense a sticker onto individual units. Typical of such prior art devices is EP0837001, which discloses a hand-held labeler that prints and dispenses labels or strips of labels. Such prior art labelers are limited in that they are designed for use with a single width of labels.
U.S. Pat. No. 5,800,669 provides a fixed-width hand-held labeler that may accept labels of different widths by moving the roll mounting members to the width of a roll of labels that has been centered on the labeler. This solution partially addresses the above width limitation, but is not inadequate for labels of very narrow widths, and does not prevent the exiting labels from shifting about.
Another useful feature found on some prior art labelers is the use of sensors in determining the beginning and end of individual labels for registration and alignment purposes. One such method, such as described in U.S. Pat. No. 5,915,864, involves marking the labels and sensing these marks. Alternatively, the translucent areas between the labels may be used in place of imprinted marks. Such methods frequently rely on detecting and measuring the velocity at which the marks pass the sensor, a method that is quite inaccurate.
Furthermore, labelers that use labels with paper backings have another drawback. The paper backing, after being separated from the labels, exits prior art labels in messy strips. The user is forced to regularly remove and discard these strips, an inconvenience that interferes with productive use.
Therefore, there is a need for a single hand-held labeling device that is able to effectively dispense labels of a plurality of widths and lengths and accurately determine the length of each individual label. It would be further advantageous if the same device could control and maintain the discarded paper backing.

Hand held electronic label dispenser for multiple label sizes


Disclosed are pharmaceutical compositions that comprise gallium complexes of 3-hydroxy-4-pyrones. These compositions provide enhanced gallium bioavailability particularly when orally administered as compared to the gallium bioavailability achieved by use of pharmaceutical compositions containing gallium salts. Compositions included in this invention are useful in providing gallium to humans and other mammals for a wide variety of medical and veterinary applications, including the treatment, prevention, or diagnosis of hypercalcemia, certain cancers, certain disorders of calcium homeostasis, and certain bone diseases including osteoporosis, osteopenia, and Paget's disease.

1. Field of the Invention
This invention relates to pharmaceutical gallium compositions, particularly those having enhanced oral bioavailability relative to simple gallium salts and methods for their use. Gallium has demonstrated pharmaceutical value for the treatment of many human and animal disorders, including hypercalcemia, cancer, and especially certain widespread degenerative or metabolic bone diseases such as osteoporosis and Paget's disease.
2. References
The following references are cited in this application as superscript numbers at the relevant portion of the application:
1. Hart and Adamson, Proceedings of the National Academy of Sciences, U.S.A., 68:1623-1626 (1971) PA1 2. Collery, U.S. Pat. No. 4,596,710 PA1 3. Adamson et al., Chemotherapy Reports, 59:599-610 (1975) PA1 4. Warrell, Jr. et al., U.S. Pat. No. 4,529,593 PA1 5. Bockman et al., U.S. Pat. No. 4,704,277 PA1 6. Warrell, Jr. et al., "Gallium in the Treatment of Hypercalcemia and Bone Metastasis", in "Important Advances in Oncology 1989", DeVita, Jr., Editor, J. P. Lippincott Company, Philadelphia, Pa. PA1 7. Porter, "The Use of Opadry, Coateric, and Surelease in the Aqueous Film Coating of Pharmaceutical Oral Dosage Forms", at pp. 317-362 of "Aqueous Polymeric Coatings for Pharmaceutical Dosage Forms", McGinity, Editor, Marcel Decker, Inc., New York, N.Y. (1989) PA1 8. Nagai et al., "Applications of HPMC and HPMCAS Aqueous Film Coatings of Pharmaceutical Dosage Forms", at pp. 81-152 of "Aqueous Polymeric Coatings for Pharmaceutical Dosage Forms", McGinity, Editor, Marcel Decker, Inc., New York, N.Y. (1989) PA1 9. Jones, "Production of Enteric Coated Capsules", Manufacturing Chemist & Aerosol News, 41:43-57 (1970) PA1 10. Messora, U.S. Pat. No. 3,927,195 PA1 11. Porter, "Coating of Pharmaceutical Dosage Forms", at Chapter 91, pp. 1633-1643, of "Remington's Pharmaceutical Sciences", Gennaro et al., Editors, 17th Ed. (1985) PA1 12. Windholz et al., The Merck Index, 9th Edition, pp. 741-742, Merck & Company, Rahway, N.J. (1976) PA1 13. Foster et al., "Gallium Nitrate: The Second Metal With Clinical Activity", Cancer Treatment Reports, 70:1311-1319 (1986) PA1 14. Hider et al., U.S. Pat. No. 4,575,502 PA1 15. Finnegan et al., Inorganic Chemistry, 26:2171-2176 (1987) PA1 16. Farrar et al., Food and Chemical Toxicology, 26:523-525 (1988) PA1 17. Ott, International Journal of Artifical Organs, 6:173-175 (1983) PA1 (a) a neutral 3:1 gallium complex of a 3-hydroxy-4-pyrone wherein said 3-hydroxy-4-pyrone has the formula ##STR1## wherein each R is independently selected from the group consisting of hydrogen and alkyl of from 1 to 6 carbon atoms; and PA1 (b) means to inhibit dissociation of said complex under acidic conditions of the gastro portion of said gastrointestinal tract PA1 (a) a neutral 3:1 gallium complex of a 3-hydroxy-4-pyrone wherein said 3-hydroxy-4-pyrone has the formula ##STR2## wherein each R is independently selected from the group consisting of hydrogen, and alkyl of from 1 to 6 carbon atoms; and PA1 (b) means to inhibit dissociation of said complex under acidic conditions of the gastro portion of said gastrointestinal tract. PA1 employing in said composition a neutral 3:1 gallium complex of a 3-hydroxy-4-pyrone wherein said 3-hydroxy-4-pyrone has the formula: ##STR3## wherein each R is selected from the group consisting of hydrogen, and alkyl of from 1 to 6 carbon atoms; and PA1 further employing in said composition means to inhibit dissociation of said complex under acidic conditions of the gastro portion of said gastrointestinal tract. PA1 (a) a neutral 3:1 gallium complex of a 3-hydroxy-4-pyrone wherein said 3-hydroxy-4-pyrone has the formula: ##STR4## wherein each R is independently selected from the group consisting of hydrogen, and alkyl of from 1 to 6 carbon atoms; and PA1 (b) means to inhibit dissociation of said complex under acidic conditions of the gastro portion of said gastrointestinal tract. PA1 The term "neutral 3:1 gallium complex of a 3-hydroxy-4-pyrone" refers to an electrostatically neutral complex of Ga.sup.+3 and 3 equivalents of the anionic form of 3-hydroxy-4-pyrone which complex is represented by the formula [Ga.sup.+3 (py.sup.-1).sub.3 ] wherein py.sup.-1 represents the anionic form of 3-hydroxy-4-pyrone which is defined below. Because such complexes do not dissociate to any significant extent in aqueous solutions maintained at a pH of from about 5 to about 9, these complexes remain predominantly electrostatically neutral in such solutions. PA1 (1) Addition of a sufficient amount of a pharmaceutically compatible buffering agent to the 3:1 complex that would bring the pH of the stomach fluids to a range of from about 5-9 and preferably from about 6-7 so that the stomach fluids would no longer disrupt the 3:1 hydroxypyrone:Ga complex. PA1 Pharmaceutically compatible buffering agents are those which, while acting as a buffering agent, do not significantly alter the ability of the neutral 3:1 gallium complex to deliver gallium to the bloodstream of the patient and are not toxic either alone or in combination with the neutral gallium complex. The particular pharmaceutically compatible buffering agent employed is not critical. Examples of preferred pharmaceutically compatible buffering agents include, by way of example, calcium carbonate (CaCO.sub.3), sodium bicarbonate (NaHCO.sub.3) and the like. On the other hand, aluminum hydroxide, Al(OH).sub.3, and other aluminum-containing compounds, by way of example, should be avoided. Other pharmaceutically compatible buffering agents are well own in the art and are recited in standard pharmaceutical manufacturing textbooks (e.g., Remington's Pharmaceutical Sciences by Mack Publishing Company). PA1 (2) Adding to the pharmaceutical composition containing the 3:1 complex an excess of free hydroxypyrone (or a salt thereof containing a physiologically acceptable cation), particularly the one used to make the 3:1 complex. Such a mixture, when dissolved in the stomach, has the effect of shifting the equilibrium among the 1:1, 2:1, and 3:1 complexes towards a preponderance of the 3:1 complex. In this embodiment, the weight of the free hydroxypyrone incorporated into the formulation is preferably 0.1 to 100 times the weight of the 3:1 complex employed in the formulation, and more preferably 0.1 to 10 times. This method, by itself, is not highly preferred but may be used in conjunction with other methods to inhibit dissociation. PA1 (3) Formulating the pharmaceutical composition that contains the 3:1 complex in delayed release form, so that a preponderance of the complex is not released until the intestinal tract is reached. An example of such a composition is to formulate the 3:1 complex with certain gels, preferably hydrogels such as a polymerized polyethylene glycol hydrogel, that adsorb the 3:1 complex and then release it after ingestion only very slowly while in the stomach. The preparation of such delayed release formulations, particularly those using hydrogels, is well known in the art. PA1 (4) Most preferably, formulating or packaging the 3:1 complex in such a way that the release of the 3:1 complex is prevented or inhibited until the basic, or less acidic, conditions of the intestinal tract are reached. Specific preferred methods include: PA1 .ANG.=.ANG.ngstrom PA1 C=Centigrade PA1 kg=kilogram PA1 M=Molar PA1 mg=milligram PA1 ml=milliliter PA1 mm=millimeter PA1 N=Normal PA1 nm=nanometers
The disclosures of each of these references are incorporated herein by reference in their entirety.

Administration of gallium complexes of 3-hydroxy-4-pyrones to provide physiologically active gallium levels in a mammalian individual


A laminated deck for a skateboard comprises a plurality of layers of graphite cloth alternating with a plurality of layers of a laminating resin. The deck is formed after treating the layers of material for between one-half hour to six hours under a vacuum at a temperature ranging from ambient temperature to 600 degrees F., depending upon the manufacturing process, whether using a hand layup process, or multiple layers of graphite cloth containing a laminating resin (“pre-preg” material). An additional lower layer of fiberglass, which can become the deck bottom, may be used in both processes. The laminated skateboard deck has properties that are at least comparable to those of wooden skateboard decks.

An embodiment of the present invention is a skateboard deck manufactured by laminating layers of carbon fiber together under heat and vacuum, over a single layer of fiberglass, and the skateboard deck produced in this manner has properties at least comparable to those of skateboard decks manufactured from woods. The earliest skateboards had decks that were made of wood, but plastics, fiberglass, KEVLAR® (Registered trademark of E.I. DuPont de Nemours Co., Wilmington, Del.), and metals have also been used to form the deck. These materials have different characteristics and properties, which affect the performance of the skateboard. For example, a longboard (which we will define here as a skateboard having a distance of at least 26 inches between the front and rear skateboard wheels) is generally preferred by skateboarders when engaging in downhill skateboarding activities, while a small board, or "Standard" size skateboard, generally having an overall length of between approximately 30 inches to approximately 33 inches, is more commonly preferred when skateboarding on ramps.
A review of prior art discloses a number of patents which describe skateboards and aspects of their manufacture.
Western (U.S. Pat. No. 6,059,307) discloses a method of manufacturing a skateboard deck using a core of wood plies surrounded by a cover comprising a pregnable cloth, such as fiberglass cloth or carbon fiber cloth. One embodiment uses a sheet of pregnable cloth placed over the upper surface and lower surface of the deck. A second sheet of pregnable cloth is placed over the first sheet, with the threads running at a 45 degree angle to each other.
Peart et al. (U.S. Pat. No. 5,716,562) discloses a method for making an injection molded, foamed, composite material skateboard. The skateboard body is formed of a composite material including a foamed structural plastic mass including plural, elongate strands of carbon fiber material distributed within the confines of the mass; the carbon fiber strands contribute within the range of about 5% to about 70& of the total weight of the mass. The skateboard body is formed by injection molding using a thermoplastic such as nylon, polypropylene and polyethylene.
Bert (U.S. Pat. No. 6,527,284 B2) discloses a skateboard deck comprising a plurality of layers of wood plies; the deck plies preferably being made from a wood such as maple. The deck further includes reinforcement members, positioned either at the front of the deck, in the area where the front wheels are fixed, in the rear where the rear wheels are fixed, or on the periphery of the deck, with the reinforcement being inserted between the upper surface layer and the lower surface layer.
In U.S. Pat. No. 6,520,518 B2 Lo discloses an aluminum skateboard including an upper plate and a lower plate, with reinforcing ribs being integrally formed on the inner wall of each plate.
Madrid (U.S. Pat. No. 6,460,868 B2) discloses a corrugated wooden skateboard deck and the use of a high density polyethylene mold in which to form the corrugations within the deck. The deck is formed from a plurality of wooden plies, interspersed with a bonding agent, and formed within the mold under conditions of pressure until the bonding agent sets.
In U.S. Pat. No. 6,435,558 B2 Osawa discloses a roller ski board formed from a light material, such as a synthetic resin, glass fiber and light metal or light compound material such as a plywood, etc.
Kay (U.S. Pat. No. 6,419,248 B1) discloses a skateboard having a deck comprising an upper and a lower platform separated by a plurality of journaled bearings, allowing for control of the skateboard.
In U.S. Pat. No. 6,293,571 B1 Wen discloses a skateboard comprising an elongated body with a hollow core and a plurality of reinforcing ribs within the deck. The elongated body, reinforcing ribs and the strengthened frame are integrally made of a moldable material, such as aluminum alloy.
Wilson (U.S. Pat. No. 6,273,440 B1, "the '440 patent" and U.S. Pat. No. 6,203,037) discloses a metal sports board, manufactured from aluminum. In the '440 patent, the metal board also includes one or more longitudinally elongated cavity-forming sections which may be filled with an appropriate light weight filler material such as a foamed plastic, a wood or wood composite material, or an inflatable bladder to aid in the strength and/or manufacturing of the metal sports board.
In U.S. Pat. No. 6,214,142 B1 Saputo discloses a method of making a skateboard deck using multiple layers of wood veneers. The method uses several layers of wood veneers in a hydraulic press, followed by shaping them on a CNC (computer numerical control) device, adding truck mounting inserts and an additional veneer layer.
In U.S. Pat. No. 5,649,717 Augustine et al. disclose a snowboard comprising a base of high density polyethylene, over which a layer of cloth, particularly hemp, is applied, and to which layers of fiberglass and a veneer panel are applied. A core made of wood, metal, KEVLAR® (Registered trademark of E.I. DuPont de Nemours Co., Wilmington, Del.) or other resilient material with metal plates or inserts is encapsulated with a layer of fiberglass. The core is placed over the veneer layer, and a final layer of cloth material is used to surround the base and core.
Parten (U.S. Pat. No. 4,921,513) discloses a method for making a wooden skateboard, in which a printed label is applied to the board lower surface by an adhesive, so that the outer periphery of the label matches the contours of the board's lower surface.
In U.S. Pat. No. 4,337,963 Stevenson discloses a skateboard wherein the skateboard pieces can be formed from plastics such as polypropylene, polyethylene, polycarbonate, or other suitable plastic which can be injection molded.
Moore (U.S. Pat. No. 4,295,656) discloses a skateboard having flexible sides, the board comprising a spine of laminated hardwoods encased between layers of fiberglass.
Smith (U.S. Pat. No. 6,182,989 B1) discloses a skateboard having laminations which are selected from at least two or more materials, one material being wood and the other material being non-wood. The non-wood material can be a layer of carbon fiber or fiberglass.
Hanson (U.S. Pat. No. 6,386,561 B1) discloses a laminated skateboard comprising a wood core with fiberglass layers.
Thus, while others described skateboard decks made from wood, wood laminates, or wood with a carbon fibre layer, no skateboard decks are described in which the entire deck is manufactured from carbon fiber, or with multiple layers of carbon fiber plus a single layer of fiberglass as a base. An embodiment of the present invention is a skateboard whose deck is manufactured from multiple layers of carbon fiber, and which has strength that is comparable to wooden skateboard decks. Embodiments of skateboard decks of the present invention are very durable, unlike wooden skateboard decks which frequently break during use. The performance of embodiments of skateboard decks of the present invention differs from that of wooden skateboard decks, such that embodiments of skateboards made using the present invention flex more than wooden skateboards, they do not slide when one is taking corners, because it is theorized that they create a greater downward force when cornering thereby minimizing the sideward forces that would cause sliding on corners, than do wooden skateboard decks. Embodiments of the skateboard decks of the present invention can be manufactured using either a manual layup process or a thermoforming process, both of which are also described herein.