An imaging device reads an output level of a pixel circuit constituting a pixel array by supplying current to the pixel circuit. It reads a signal level and reset level from the pixel circuit by supplying it with the current from a current source circuit, and stores them into a line memory. A pixel level of the pixel circuit is obtained by a differential amplifier that outputs the difference between the signal level and reset level of the same pixel circuit. The gate potential of a current copier transistor that supplies the read current is set at a value that enables the read current to take a constant value from column to column of the pixel array. The image device can suppress variations in the current copier circuit provided for each array column of the pixel circuits, thereby reducing string-like noise in the image picked up.

1. Field of the Invention
The present invention relates to an imaging device capable of suppressing variations between array columns consisting of pixel circuits constituting an image sensor.
2. Description of Related Art
FIG. 6 is a circuit diagram showing a schematic configuration of a conventional imaging device. The conventional imaging device is described in "128 Mb/s Multiport CMOS Binary Active-Pixel Image Sensor" by Roger A. Panicacci, et. al., ISSCC96 SESSION 6, PAPER TP 6.5 (pp. 80–81 and 372–373), a part of which is shown in this figure. In FIG. 6, the reference numeral 101 designates a unit pixel circuit constituting a pixel array with other unit pixel circuits 101. The reference numeral 102 designates a reset switch for resetting a photodiode 103 of the unit pixel circuit 101; 103 designates the photodiode for generating a potential corresponding to an amount of input light; 104 designates a source follower transistor for reading and amplifying the output potential of the photodiode 103; and 105 designates an output selecting transistor for the output operation of the unit pixel circuit 101 selected by an external input signal. The unit pixel circuit 101 consists of the reset switch 102, photodiode 103, source follower transistor 104, and output selecting transistor 105.
The reference numeral 106 designates a column memory provided for each array column of the pixel array. For the sake of simplicity, only a pair of unit pixel circuit 101 and column memory 106 is shown. The reference numeral 107 designates a bias transistor for supplying the source follower transistor 104 with a constant current when reading the output potential from the unit pixel circuit 101 to the column memory 106; 108 designates a sampling transistor for leading the output potential of the source follower transistor 104 to a clamp capacitor 109; 109 designates the clamp capacitor for clamping the output potential of the source follower transistor 104; 110 designates a clamp transistor for clamping the output side of the clamp capacitor 109; and 111 designates an output transistor for generating pixel data from the column memory 106. The column memory 106 consists of the bias transistor 107, sampling transistor 108, clamp capacitor 109, clamp transistor 110, and output transistor 111. The reference numeral 112 designates an input transistor of a current-mirror circuit for determining the output current of the bias transistor 107; and 113 designates an output line for connecting the unit pixel circuit 101 to the column memory 106.
Next, the operation of the conventional imaging device will be described.
First, the reset switch 102 resets the photodiode 103. Receiving the incident light, the photodiode 103 stores electric charges, and outputs a potential corresponding to an amount of the incident light. The potential is applied to the gate of the source follower transistor 104. After applying the light to the photodiode 103 for a fixed time period to store the electric charges, a controller (not shown) supplies the gate of the output selecting transistor 105 with a signal for selecting the unit pixel circuit 101. Thus, a circuit is established between the source follower transistor 104 and the bias transistor 107 so that the signal level of the unit pixel circuit 101 is supplied to the column memory 106 via the output line 113.
The output line 113 is provided with a signal level equal to the potential output from the photodiode 103 minus the threshold voltage of the source follower transistor 104 in response to the incident light. The signal level applied to the output line 113 is fed to the column memory 106. In the column memory 106, the sampling transistor 108 controls its sampling timing by switching, thereby supplying the signal level to the input side of the clamp capacitor 109. In this case, the output side of the clamp capacitor 109 is fixed at the clamp potential by the output of the clamp transistor 110. Subsequently, the output of the clamp transistor 110 is turned off to bring the output side of the clamp capacitor 109 into a floating state. Then, the photodiode 103 is reset again. In this case, the reset level, which is equal to the potential output of the photodiode 103 minus the threshold voltage value of the source follower transistor 104, is supplied to the input side of the clamp capacitor 109 via the output line 113. Thus, the potential at the output side of the clamp capacitor 109 that is held at the fixed clamp potential is increased by the potential given by the following expression.(reset level of photodiode 103)−(signal level of photodiode 103)The output transistor 111 carries out predetermined processing of the potential increased from the clamp potential, and outputs the result from the column memory 106 as its pixel output.
Using such correlated double sampling, the conventional imaging device compares the signal level with the reset level output from the same pixel, thereby suppressing fixed pattern noise resulting from the variations in the threshold voltage values of the transistors constituting the unit pixel circuit 101 and the like.
With the foregoing configuration, the conventional imaging device can suppress the fixed pattern noise resulting from the variations in the threshold voltages of the transistors constituting the unit pixel circuit 101. However, it has a problem of generating fixed vertical string-like pattern noise in an image on the imaging device if the bias transistor 107 in the column memory 106, which is disposed in each column of the array consisting of the unit pixel circuits 101, has variations, and hence the bias current has variations between the array columns.
This will be described in more detail. The fixed pattern noise appearing in the image picked up arises from the variations in the output potential between the pixel circuits, which is affected by the variations in the threshold values of the source follower transistors 104 and bias transistors 107. The noise arising from the variations in the characteristics of the source follower transistors 104 appears at random in the image. In contrast, the noise arising from the variations in the characteristics of the bias transistors 107 appears as the string-like noise because it brings about the variations in the array columns. From the characteristics of the human eye, the visual perception for the string-like noise is about three times more acute than for the random noise. Accordingly, the variations in the bias transistors 107 that generate the string-like noise must be reduced about ⅓ or less of the variations in the source follower transistors 104 that produce the random noise. However, the variations in the bias transistors 107 and source follower transistors 104 are nearly the same, because they are formed in the same device. In addition, the bias transistors 107 constitute a current-mirror circuit in the circuit configuration, and their characteristic variations have equal to or greater effect on the potentials to be sampled than the characteristic variations in the source follower transistors 104. As a result, the configuration of the conventional imaging device has a problem of making it difficult to suppress the string-like noise.

Imaging device with suppressed inter-column variations


A solid-state imaging device that suppresses crosstalk of light in a semiconductor substrate that caused by diffraction of light is disclosed. According to one aspect of the present invention, there is provided a solid-state imaging device comprising a plurality of pixels, each pixel comprising a photoelectric conversion element that is provided in a semiconductor substrate and performs photoelectric conversion of incident light to store signal charges, a floating junction that is provided in the semiconductor substrate in the proximity of the photoelectric conversion element and temporarily stores signal charges, and a transfer transistor that transfers the signal charges stored in the photoelectric conversion element to the floating junction, wherein at least one transfer transistor includes a gate electrode extended to cover a corresponding photoelectric conversion element.

1. Field of the Invention
The present invention relates to a solid-state imaging device, and more particularly to a solid-state imaging device that suppresses crosstalk of light.
2. Description of the Related Art
In a solid-state imaging device, e.g., a device such as a CMOS image sensor, a pixel size is reduced for the purpose of realizing a miniaturization, a higher accuracy, and others. Therefore, a reduction in size of a photoelectric conversion element and/or a transistor constituting a pixel has been advanced. Since a quantity of signal charges that can be stored in the photoelectric conversion element is decreased when a reduction in size advances, each pixel tends to become sensitive to various kinds of noises, such as thermal noise, dark current noise, and crosstalk of light.
Jpn. Pat. Appln. KOKAI Publication No. 2005-129965 discloses a solid-state imaging device that suppresses occurrence of thermal noise or dark current noise to improve a signal-to-noise (S/N) ratio of an image. However, this publication does not describe about crosstalk.
A reduction in size of a photoelectric conversion element makes it difficult to allowing incident light to be condensed by a microlens to enter the photoelectric conversion element alone. According to the solid-state imaging device disclosed in the above patent document, a gate electrode of a transfer transistor is disposed to be adjacent to a photoelectric conversion element. In a solid-state imaging device having such a configuration, for example, incident light is condensed by the microlens to enter the photoelectric conversion element through a space between metal wiring lines. However, a phenomenon that the incident light irradiates not only the photoelectric conversion element but also a gate electrode of a transfer transistor disposed adjacent thereto occurs. When this phenomenon occurs, a part of the incident light causes a diffraction phenomenon at an edge of the gate electrode. Diffracted light diffracted by the gate electrode is propagated through a semiconductor substrate to reach a neighboring floating junction and/or a photoelectric conversion element. Such diffracted light produces crosstalk of light, thereby deteriorating pixel characteristics.


A method and apparatus for continuously removing oil from oil-bearing solids such as tar sands, vegetables or other solid materials using a solvent is provided. By providing a pressure differential between the exterior and interior of an oil extraction chamber, substantially oil free solids may be removed from the oil extraction chamber through a solids extraction channel without removing any substantial volume of solvent through the solids extraction channel.

Numerous oil-bearing solid materials exist in nature. These include tar sands and vegetable products such as soy beans and peanuts. Other non-natural oil containing solids additionally exist, such as contaminated dirt resulting from oil spills or other environmental accidents. When these oils are successfully removed from these solid or semi-solid materials, a raw oil product is recovered which can be utilized for numerous purposes including heating, cooking and in the production of synthetic materials such as plastic or rubber.
The challenge of removing oils from either natural or unnatural sources is significant based on the economic and environmental costs associated with the accumulation and processing of these materials. To compete in a global market, the processing of these materials must be performed at a cost low enough to compete with other energy sources such as traditional oil production or coal mining. For example, in the processing of tar sands which contain oil-bearing bitumen, the oil-bearing sands must first be mined, the tar sand processed and the sand cleaned sufficiently to alleviate environmental concerns upon disposal or proper placement back into the environment.
Numerous processes have been utilized to recover oil from these various natural and non-natural occurring oil-bearing materials. One particular cold water method for separating oil from sand is shown in U.S. Pat. No. 1,567,983 where oil laden sand is passed over a plurality of washing drums which loosen the oil from the sand material. The oil, having a lower specific gravity then water, rises to the water surface for collection while the sand settles to the bottom for collection. This method is inefficient based on the amount of oil remaining in contact with the sand material and the amount of water which must be used.
In another method which utilizes hot water, the oil-bearing materials are subject to a jet of high pressure steam and introduced into a mixing vessel with hot water at a temperature near the boiling point. Low pressure steam is jetted into the mixture in the mixing vessel, which produces a froth of oil, water, and tar. As the froth accumulates above the level of the water in the tank the froth can be collected and recovered. These hot water batch processes are generally ineffective due to the high cost of heating the water and additionally requires a significant capital investment in equipment.
Other methods for removing oil from oil-bearing materials use organic solvents for extraction. These solvents include gasoline, naphtha, or other materials derived from petroleum based products. One particular process which utilizes organic solvents for extraction is disclosed in U.S. Pat. No. 4,389,300 to Mitchell. Mitchell discloses a vertical extraction zone where oil laden materials are introduced into the top of the extraction zone while liquid solvent is injected into an intermediate level of the vertical bed of materials while maintaining a substantially gaseous phase in contact with a lower portion of the bed. The liquid phase is prevented from flowing downwardly by attempting to maintain a gaseous phase at a sufficient pressure in the lower portion of the extraction zone The solids are removed from the lower portion of the bed with a screw-type auger assembly.
In U.S. Pat. No. 4,401,551, also issued to Mitchell, a process is described which again utilized a two-phase interface of gaseous and liquid solvent in a vertical bed of oil-bearing materials where the treated sand is removed with an auger assembly. The invention also utilizes recovered solvent at a temperature and pressure sufficient to maintain the solvent in a liquid phase to contact the oil-bearing bituminous sand to improve recovery. However, in both of the Mitchell patents the screw-type auger assembly allows a significant loss of solvent and the process is difficult to operate as a result of the gas in the lower portion of the chamber migrating upwards while the liquid solvent falls to the bottom of the extraction chamber.
In U.S. Pat. No. 5,281,732 issued to Frank, a batch method for extracting oils from vegetables is disclosed where an extraction chamber is filled with an oil-bearing material, the air purged from the extraction zone and a normally gaseous solvent introduced into the extraction chamber in a liquid phase. The liquid solvent is then pumped through the oil-bearing materials which extracts the oil from the oil bearing solids. The recovered oil and solvent are then transported to a separator in a liquid phase for separation and eventual recovery of the oil and solvent. Due to the batch nature of this operation, this type of process is inefficient for processing substantial volumes of oil-bearing solid materials and does not efficiently remove all of the solvent from the solid materials during processing.
Thus there is a substantial need for a method and apparatus which is efficient, cost effective, environmentally safe and can be performed in a continuous mode to process tremendous volumes of oil laden materials such as tar sands or soil from environmental clean-up sites. Furthermore, a need exists for an apparatus and method which is relatively mobile and which can be transported to a processing site at a potentially remote location.

Method for recovering oil from an oil-bearing solid material


The oscillating mechanical device comprises a shaft on which an oscillating member is mounted, and which is resiliently urged towards a middle angular equilibrium position, together with a single-phase induction motor whose rotor is coupled to the shaft so as to enable oscillations of the shaft to be sustained. According to the invention, the stator of the single-phase induction motor is fed with an alternating drive signal whose frequency is adjusted to the vicinity of the natural frequency of oscillation of the mechanical device. More particularly, the frequency of the drive signal of the stator is set to lie in the frequency range f-0.8 Hz; f+0.1 Hz!, where f represents the natural frequency of oscillation of the mechanical device, and is preferably set to the natural frequency of oscillation of the mechanical device with a tolerance of plus or minus one-tenth of one hertz. The device is applicable to card web combs used in the textile industry.

In French patent No. 1 351 572, the Applicant has already proposed an oscillating mechanical device comprising a shaft having an oscillating member mounted thereon and which is urged resiliently towards an angular equilibrium position by means, in particular, of a torsion bar housed inside the shaft. The shaft is coupled to the rotor of a single-phase induction motor. In theory, once the oscillating device has been set into motion, the shaft oscillates with oscillations of given amplitude and at a fixed frequency which is equal to the natural frequency of the mechanical device and which is independent of the frequency of the AC drive signal fed to the stator of the motor. This natural frequency depends in a known manner solely on the torsion characteristics of the resilient return means and on the moment of inertia of the masses subjected to rotary drive, i.e., in particular, the inertia of the shaft, of the member carried by the shaft, and of the rotor. Once the device is oscillating at its natural frequency, the single-phase induction motor serves solely to provide sufficient energy to compensate for damping due to friction, thereby sustaining oscillations.
Such an oscillating device is used more particularly in the textile industry as a simple way of implementing a card web comb for detaching the web at the outlet of a carding machine, and at present the highest possible rate of oscillation is less than 4,000 strokes/minute, which corresponds to a natural frequency of oscillation of about 66.7 Hz. In practice, e.g. with combs oscillating at 2,817 strokes/minute, i.e. combs whose natural frequency of oscillation is 46.95 Hz, the frequency of the AC drive signal fed to the stator of the single-phase induction motor is adjusted to between 53 Hz and 63 Hz. It is known that in this frequency range, the amplitude of comb oscillations is stable and reaches a maximum at a frequency of 54 Hz. Also, in compliance with theory concerning the operation of a card web comb as recalled above, within the range of frequencies and whatever the frequency of the signal fed to the stator, the frequency of oscillation of the comb is constant and equal to the natural frequency of the comb. The oscillations of the comb are thus completely asynchronous relative to the driving frequency applied to the stator of the single-phase induction motor.
A single-phase induction motor is a motor of simple design and it is reliable. When such a motor is used to implement card web combs, it serves advantageously to reduce maintenance costs, compared with using motors that are more sophisticated, e.g. brushless motors.
However, until now, the use of a single-phase induction motor for sustaining oscillations of an oscillating device of the card web comb type has suffered from two main drawbacks.
The first drawback is associated with the fact that a single-phase induction motor draws a large amount of current since its rotor is subjected to frequent reversals in its direction of rotation under the effect of the resilient return action applied to the shaft which is coupled to the rotor. This drawback leads to using an induction motor rated for power that is overdimensioned compared with the rate at which it needs to feed mechanical energy to the comb in order to sustain oscillations.
The second drawback is associated with starting a card web comb that uses a single-phase induction motor. On starting, when the rotor of the single-phase induction motor is stationary and voltage is applied to its stator, the motor develops zero driving torque, so it is necessary to impart a preferred direction of rotation to the rotor in order to start it. When stationary, the single-phase induction motor behaves like a single-phase transformer whose primary and secondary windings carry very high currents. The rotor, and consequently the torsion bar, then begins to vibrate under the effect of intense eddy currents which are induced in the magnetic masses of the motor. In theory, these vibrations serve automatically to start oscillations in the shaft at the natural frequency of oscillation of the mechanical device, and the angular amplitude of the oscillations tends to increase rapidly until it reaches a stable maximum value. In practice, oscillations do not always start. Therefore, to trigger oscillations it is necessary either to start the comb manually by applying torque to the torsion bar, or else to equip the single-phase induction motor with an external starter device.
In order to mitigate the above-specified problems, attempts have been made to replace the single-phase induction motor with a motor that is more sophisticated, e.g. of the brushless motor or DC motor type. That is the solution recommended in European patent EP 519 878 which, in general terms, teaches firstly replacing the single-phase induction motor with a motor that delivers constant torque regardless of the speed of rotation of the rotor, and whose direction of rotation can be reversed under electrical control, and secondly servo-controlling reversal of the direction of rotation as a function of the amplitude of comb oscillation so as to provide an oscillating system. The same solution is adopted in Russian patent application SU 1 227 726.

Oscillating mechanical device, in particular a card web comb for a textile machine, in which oscillations are sustained by means of a single-phase induction motor


An image processing method includes inputting electronic image data to be scrambled, decomposing the input electronic image data into n colors (n is an integer) and producing m pieces of color decomposition data for each color (m is an integer), producing palette data in which each of the m pieces of color decomposition data is assigned a palette identification number, producing palette exchange data based on predetermined conditions, exchanging palette identification numbers of the color decomposition data based on the produced palette exchange data, and synthesizing the m pieces of color decomposition data whose palette identification numbers are exchanged, encoding the synthesized data, and outputting the encoded data as a piece of scrambled image data.

1. Field of the Invention
The present invention relates to an image processing method.
2. Description of the Related Art
In recent years, as digital still cameras or the like have been widely used, personal users who handle digitized images and pictures have been increasing. Many of the images and pictures have been increasingly disclosed to the public through the Internet or intranets. In some cases, specific image data is distributed at charge to a person who wishes to buy the data, or to a specific user through a network site, which can be accessed by unspecified users. In such cases, generally, a password is set to obtain the image, or the image to be distributed is scrambled or mosaicked. To distribute a scrambled image, a transmitter side must have scrambling means, and a receiver side must have scramble releasing (descrambling) means. A scanning line signal switching method or a scanning line shifting method, utilizing random arrangement, are known as the image scrambling methods. In the former method, the order of data in a scanning line is changed. In the latter method, data is shifted from one scanning line to another. Further, Jpn. Pat. Appln. KOKAI Publication No. 5-103326 discloses a method for produce a scrambled image by forming new two field images from two field images in one frame so as not to reduce the compression ratio.
In the case where the password setting method is employed, it is necessary to use a password management server and collectively manage the access rights of all persons who wish to buy the image data on the server, although no hardware is required. In the case where the scramble distribution method is employed, both software and hardware load is required, although there is no need of managing the access rights.
Since the scrambling process in the transmitter side is performed independent of a compressing process, the following drawback occurs: if the scrambling process is performed after the compressing process, it is necessary to transmit data without an error in descrambling. On the other hand, if the compressing process is performed after the scrambling process, the compression is reduced due to the reduction of a correlation between adjacent pixels.


A washer/dryer combination used for washing and drying articles such as clothing in the same machine. The washer/dryer combination includes a body having a treatment chamber defined within the body, a front side including an opening, and a door attached to the front side and selectively covering the opening. The door includes a front wall, a back wall, a cavity defined between the walls, and a pair of air ducts disposed within the cavity. A first air duct includes a hot air outlet and the second air duct includes an exhaust air inlet. The washer/dryer combination further includes a heater and blower unit for blowing hot air into the chamber of the body via the hot air outlet. A first air conduit has a first end matingly engaging the heater and blower unit and a second end matingly engaging the first air duct. A second air conduit has a first end and second end where the first end matingly engages the second air duct. The washer/dryer combination can further include a lint guard disposed within the second air conduit. At least one seal is provided between the door and the opening of the front side of the body.

The present invention relates generally to laundry machines. More particularly, the present invention relates to an improved washer/dryer combination for use in the washing and drying of clothes, bed sheets, towels and other articles.
As is well known, a washing machine is an appliance for separating dirt from articles to be washed, such as clothing, by sequentially carrying out various operations such as liquid feeding, washing, rinsing, dehydrating, and draining cycles. Generally, the washing machine has an outer tub for receiving a washing liquid and a spin tub accommodated in the outer tub for holding the articles to be washed.
While the washing cycle is being executed, a pulsator, which is driven by a motor, generates a swirling liquid in the spin tub, so the articles which are placed in the spin tub are washed by means of the swirling liquid.
In addition, while the dehydrating cycle is being executed, the motor rotates the spin tub, so the articles are forced toward a side wall of the spin tub due to a centrifugal force. Accordingly, the washing liquid contained in the articles is drained out of the washing machine through discharging holes which are formed in the side wall of the spin tub.
Recently, washing machines have been designed which not only wash the articles but can also dry them. These kinds of washing machines, which are called washing/drying machines, are advantageous for a number of reasons. They can reduce drying time and do not require a separate location for drying the articles. These machines save time and effort for the user. Clothing and other articles do not need to be washed in one machine then removed and loaded into a separate machine for drying. Perhaps just as importantly, a combination washer/dryer is advantageous from the standpoint of a laundromat since each machine can perform either function thus allowing more machines to be in use at one time.
Several washer/dryer combination designs are known. One such device is shown in U.S. Pat. No. 5,718,130. This device is a washing/drying machine which employs a top-loading spin tub rotating around a vertical axis. A blower is mounted on the base portion of the spin tub and blows heated air upwardly so as to direct the heated air toward the side wall of spin tub and onto articles placed in the spin tub.
A disadvantage of this device is that it does not employ a hot air outlet in the door which would allow hot air to be blown directly on the articles for drying. Another disadvantage of this device is that it is not a front-loading machine, thus, reducing its capacity.
Another known device is shown in U.S. Pat. No. 5,121,615. This device is a front-loading combination washer/dryer which includes a housing with a perforated drum disposed in the housing to ensure that all the hot air enters the rotatable drum. The device provides a drying device to be used in conjunction with a washing machine. A stationary drum positioned around the rotatable drum prevents hot air from escaping from the housing of the drying device without entering the rotatable drum so as to dry clothes. A plurality of circumferentially spaced ribs extend from the outer surface of the perforated wall toward the stationary drum, dividing the clearance between the two drums into several isolated chambers.
A disadvantage of this device is that it needs additional components to ensure that all of the hot air enters the drying chamber. Another disadvantage of this machine is that the door is not employed as either a hot air inlet or an exhaust outlet.
Still another known device is shown in U.S. Pat. No. 5,111,673. This device is a washing-drying machine which has a tub mounted in a prism-shaped housing by a pair of tilting shafts in order to carry out the washing-rinsing-spinning steps while the tub is in a substantially vertical orientation and to carry out the warm-air drying step with the tub in a substantially horizontal orientation. The tilting shafts are arranged on a horizontal axis extending through diagonally opposite corners of the housing so that the capacity of the tub can be maximized, even though the tub tilts.
A disadvantage of this device is that it requires tilting of the tub from a vertical axis for washing to a horizontal axis for drying. This construction obviously adds to the complexity of the machine, and hence, its cost.
Yet another known device is shown in the U.S. Pat. No. 5,074,131. The device is a washing/drying machine capable of effecting washing and drying as a continuous process. Washing, rinsing, dehydrating and drying are performed while a rotary basket is retained in a vertical position. After the dehydration, the rotary basket is inclined and is rotated on its axis, so that an opening end of the rotary basket is located slightly higher than the horizontal. In this state, hot air for drying is blown into the rotary basket from the opening side.
A disadvantage of this device is that it requires tilting of the rotary basket axis to switch the machine from the washing phase to the drying phase. Such tilting would not be necessary if the machine were simply a front-loading washer employing a basket which rotates on a horizontal axis.
A further known device is shown in U.S. Pat. No. 5,029,458. This device is a washing and drying machine which has a drum mounted in an outer tank for rotation about a substantially horizontal axis and a reversible motor operable at a fixed speed for driving the drum. During washing and drying operations, the direction of rotation of an output shaft of the motor is switched in short periods while a speed-changing device transmits the rotation of the output shaft of the motor to the drum axle at a reduced speed. During dehydration, the motor operates unidirectionally and the speed-changing device transmits the unidirectional rotation of the motor output shaft to the drum axle with a speed reduction in an initial stage of the dehydration operation and, thereafter, without speed reduction.
A disadvantage of this device is that it is complex and requires the changing of the speed of the output shaft of a motor between dehydration and drying stages. The machine is also a top loader, limiting its capacity.
A still further known device is shown in U.S. Pat. No. 4,757,699. This device is a washing machine which includes a wash tub, a basket for receiving laundry and mounted for rotation within the wash tub, and heater elements which are located within the chamber to thereby heat the washing liquid discharged into the chamber. The device further includes an air drying circuit whereby air is recirculated through an air duct by means of a fan from the bottom of the wash tub to the chamber. The recirculated air is heated by the heating elements.
While this machine appears to have a tub rotating around a horizontal axis, there does not appear to be any mention of the door of the machine. Certainly, there is no mention of employing an aperture in the door either for blowing hot air on the articles or for venting exhaust air from the machine.
Another known device is shown in U.S. Pat. No. 4,270,281. This device is a washing and drying machine having a perforated drum rotatable with a liquid container having, in its upper portion, a recess in which is disposed a heat-register or heating element and a reflector providing for direct irradiation of the drum.
A disadvantage of this device appears to be that it requires the heating element to be disposed within the drum, thus exposing the heating element to detergent in the washing liquid, possibly comprising its longevity.
Accordingly, it has been considered desirable to develop a new and improved washer/dryer combination which would overcome the foregoing difficulties and others while providing better and more advantageous overall results.


A novel receptor, “LDL-receptor-related protein-5” (“LRP-5”), is provided, along with encoding nucleic acid. The gene is associated with type 1 diabetes (insulin dependent diabetes mellitus), and experimental evidence provides indication that it is the IDDM susceptibility gene IDDM4. In various aspects the invention provides nucleic acid, including coding sequences, oligonucleotide primers and probes, polypeptides, pharmaceutical compositions, methods of diagnosis or prognosis, and other methods relating to and based on the gene, including methods of treatment of diseases in which the gene may be implicated, including autoimmune diseases, such as glomerulonephritis, diseases and disorders involving disruption of endocytosis and/or antigen presentation, diseases and disorders involving cytokine clearance and/or inflammation, viral infection, elevation of free fatty acids or hypercholesterolemia, osteoporosis, Alzheimer's disease, and diabetes.

Diabetes, the dysregulation of glucose homeostasis, affects about 6% of the general population. The most serious form, type 1 diabetes, which affects up to 0.4% of European-derived population, is caused by autoimmune destruction of the insulin producing β-cells of the pancreas, with a peak age of onset of 12 years. The β-cell destruction is irreversible, and despite insulin replacement by injection patients suffer early mortality, kidney failure and blindness (Bach, 1994; Tisch and McDevitt, 1996). The major aim, therefore, of genetic research is to identify the genes predisposing to type 1 diabetes and to use this information to understand disease mechanisms and to predict and prevent the total destruction of β-cells and the disease.
The mode of inheritance of type 1 diabetes does not follow a simple Mendelian pattern, and the concordance of susceptibility genotype and the occurrence of disease is much less than 100%, as evidenced by the 30–70% concordance of identical twins (Matsuda and Kuzuya, 1994; Kyvik et al, 1995). Diabetes is caused by a number of genes or polygenes acting together in concert, which makes it particularly difficult to identify and isolate individual genes.
The main IDDM locus is encoded by the major histo-compatibility complex (MHC) on chromosome 6p21 (IDDM1). The degree of familial clustering at this locus, λs=2.5, where λs=P expected [sharing of zero alleles at the locus identical-by-descent (IBD)]/P observed [sharing of zero alleles IBD] (Risch 1987; Todd, 1994), with a second locus on chromosome 11p15, IDDM2, the insulin minisatellite λs=1.25 (Bell et al, 1984; Thomson et al, 1989; Owerbach et al, 1990; Julier et al, 1991; Bain et al, 1992; Spielman et al, 1993; Davies et al, 1994; Bennett et al, 1995). These loci were initially detected by small case control association studies, based on their status as functional candidates, which were later confirmed by further case-control, association and linkage studies.
These two loci, however, cannot account for all the observed clustering of disease in families (λs=15), which is estimated from the ratio of the risk for siblings of patients and the population prevalence (6%/0.4) (Risch, 1990). We initiated a positional cloning strategy in the hope of identifying the other loci causing susceptibility to type 1 diabetes, utilising the fact that markers linked to a disease gene will show excess of alleles shared identical-by-descent in affected sibpairs (Penrose, 1953; Risch, 1990; Holmans, 1993).
The initial genome-wide scan for linkage utilising 289 microsatellite markers, in 96 UK sibpair families, revealed evidence of linkage to an additional eighteen loci (Davies et al, 1994). Confirmation of linkage to two of these loci was achieved by analysis of two additional family sets (102 UK families and 84 USA families), IDDM4 on chromosome 11q13 (MLS 1.3, P=0.003 at FGF3) and IDDM5 on chromosome 6q (MLS 1.8 at ESR). At IDDM4 the most significant linkage was obtained in the subset of families sharing 1 or 0 alleles IBD at HLA (MLS=2.8; P=0.001; λs=1.2) (Davies et al, 1994). This linkage was also observed by Hashimoto et al (1994) using 251 affected sibpairs, obtaining P=0.0008 in all sibpairs. Combining these results, with 596 families, provides substantial support for IDDM4 (P=1.5×10−6) (Todd and Farrall, 1996; Luo et al, 1996).

Method of screening for modulator of LRP5 activity


A document classification and analysis system includes a processor, a memory including one or more storage regions, and a non-transitory computer-readable medium having stored thereon instructions that, when executed, cause the processor to perform a method. The method includes receiving a document including a plurality of words, performing morpheme analysis on the document to extract original forms of the words, tagging each of the words based on a corresponding part-of-speech, determining location information of the words based on an order of the words in the document, applying one or more lexicon lists to the document to classify each of the words, and storing the location information.

The background section provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent the work is described in this section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
In existing methods for classifying and analyzing records or documents including text, the frequency of the appearance of terms (or words) in a document has been used to determine key terms (or keywords). The document is classified or analyzed by matching frequently appearing terms, i.e., the key terms, with a provided set of terms.
When categorizing a document including text using only the frequency of terms, it is difficult to find the correlation between terms since the frequency of each term is separately calculated.

Apparatus and method for classifying and analyzing documents including text


A three-dimensional printed dental device formed from rapid prototyping with printable polymerizable materials, the dental device comprising a polymeric composition, wherein the polymeric composition, after curing, has at least one property of flexural strength, flexural modulus, fracture toughness, and work of fracture that is at least 20% greater in measured value at 37° C. in comparison to measured value at 23° C.

The present invention relates generally to rapid prototyping systems, specifically, 3D printing systems for making multiple layered dental devices such as, for example, artificial teeth, dentures, splints, veneers, inlays, onlays, orthodontics, aligners, retainers, copings, frame patterns, crowns and bridges, models, appliances and the like. More particularly, it is related to the use of ink-jet, fused deposition modeling (FDM), selective laser sintering (SLS), stereolithography (SLA), digital light processing (DLP) or their combinations to build-up the dental devices as three-dimensional objects from many material systems and novel resin systems of this invention. Ink-jet printing system dispenses materials through ink-jet printing head to form 3D object, which harden by cooling, polymerization, and light irradiation. FDM extrudes thermoplastic materials throughout nozzle to build 3D object. SLS uses laser as power source to sinter powdered materials to form solid objects. SLA using laser beam traces out the shape of each layer and hardens the photosensitive resin in a vat (reservoir or bath). DLP system builds three-dimensional objects by using the Digital Light Processor (DLP) projector to project sequential voxel planes into liquid resin, which then caused the liquid resin to cure.
In general, rapid prototyping refers to a conventional manufacturing process used to make parts, wherein the part is built on a layer-by-layer basis using layers of hardening material. Per this technology, the part to be manufactured is considered a series of discrete cross-sectional regions which, when combined together, make-up a three-dimensional structure. The building-up of a part layer-by-layer is very different than conventional machining technologies, where metal or plastic pieces are cut and drilled to a desired shape. In rapid prototyping technology, the parts are produced directly from computer-aided design (CAD) or other digital images. Software is used to slice the digital image into thin cross-sectional layers. Then, the part is constructed by placing layers of plastic or other hardening material on top of each other. There are many different techniques that can be used to combine the layers of structural material. A final curing step may be required to fully cure the layers of material for some of the techniques. The application of sealer may be needed to form a dense 3D objects for some of the techniques, such as inkjet printing of a powder bed or FDM. Additional milling may be added to some of the techniques too.
Ink-jet printing technology is a rapid prototyping method that can be used to fabricate the three-dimensional object. In one well known ink-jet printing method that was developed at Massachusetts Institute of Technology, as described in Sachs et al., U.S. Pat. No. 5,204,055, printer heads are used to discharge a binder material onto a layer of powder particulate in a powder bed. The powdered layer corresponds to a digitally superposed section of the object that will be produced. The binder causes the powder particles to fuse together in selected areas. This results in a fused cross-sectional segment of the object being formed on the platform. The steps are repeated for each new layer until the desired object is achieved. In a final step, a laser beam scans the object causing the powdered layers to sinter and fuse together if needed. In another ink-jet printing process, as described in Sanders, U.S. Pat. Nos. 5,506,607 and 5,740,051, a low-melting thermoplastic material is dispensed through one ink-jet printing head to form a three-dimensional object. A second ink-jet printer head dispenses wax material or other supporting material to form supports for the three-dimensional object. After the object has been produced, the wax supports are removed, and the object is finished as needed. MultiJet printers, such as, the high-quality PolyJet and MultiJet 3D printing processes use a UV light to crosslink a photopolymer. However, rather than scanning a laser to cure layers, a printer jet sprays tiny droplets of the photopolymer (similar to ink in an inkjet printer) in the shape of the first layer. The UV lamp attached to the printer head crosslinks the polymer and locks the shape of the layer in place. The build platform then descends by one layer thickness, and more material is deposited directly onto the previous layer. Triple-jetting technology (PolyJet) used in Stratasys Objet 500 Connex3, is the most advanced method of PolyJet 3D printing. This technology performs precise printing with three materials and thus makes three-color mixing possible.
Fused deposition modeling (FDM) technology was developed and implemented at first time by Scott Crump, Stratasys Ltd. founder, in 1980s. What is good about this technology that all parts printed with FDM can go in high-performance and engineering-grade thermoplastic. FDM is the only 3D printing technology that builds parts with production-grade thermoplastics, so things printed are of excellent mechanical, thermal and chemical qualities. 3D printing machines that use FDM Technology build objects layer by layer from the bottom up by heating and extruding thermoplastic filament. Along to thermoplastic a printer can extrude support materials as well. Then the printer heats thermoplastic till its melting point and extrudes it throughout nozzle to a build platform. To support upper layer the printer may place underneath special material that can be dissolved after printing is completed. When the thin layer of plastic binds to the layer beneath it, it cools down and hardens. Once the layer is finished, the base is lowered to start building of the next layer. This technology is considered to be simple-to-use and environment-friendly. Different kind of thermoplastics can be used to print dental objects.
Selective Laser Sintering (SLS) is a technique that uses laser as power source to form solid 3D objects. This technique was developed by Carl Deckard, a student of Texas University, and his professor Joe Beaman in 1980s. The main difference between SLS and SLA is that it uses powdered material in the vat instead of liquid resin as stereolithography does. Unlike some other additive manufacturing processes, such as stereolithography (SLA) and fused deposition modeling (FDM), SLS doesn't need to use any support structures as the object being printed is constantly surrounded by unsintered powder. Due to wide variety of materials that can be used with this type of 3D printer the technology is very popular for 3D printing customized products. SLS requires the use of high-powered lasers, which makes the printer to be very expensive. Extensive surface finishing is required for dental objects made with this process.
SLA 3D printing method was patented by Charles Hull, co-founder of 3D Systems, Inc. in 1986, which converts liquid plastic into solid 3D objects. SLA 3D printers work with excess of liquid resin that hardens and forms into solid object by irradiation. Parts built usually have smooth surfaces but its quality very depends on the quality of SLA machine used. After plastic hardens a platform of the printer drops down (top down printer) or move up (bottom up printer) in the tank a fraction of a millimeter and laser forms the next layer until printing is completed. Once all layers are printed the object needs to be rinsed with a solvent and then placed in a post-cure oven to finish processing.
Digital Light Processing is another 3D Printing process very similar to stereolithography. The DLP technology was created in 1987 by Larry Hornbeck of Texas Instruments and became very popular in Projectors production. It uses digital micro mirrors laid out on a semiconductor chip. 3D inkjet, DLP and SLA all works with photopolymers. The difference between SLA and DLP processes is a different light source. DLP method projects sequential voxel planes into liquid resin, which then caused the liquid resin to cure. The material to be used for printing is liquid resin that is placed in the transparent resin container. The resin hardens quickly when affected by irradiation of light. The printing speed is pretty impressive, especially with Carbon3D's CLIP (Continuous Liquid Interface Production) technology. The layer of hardened material can be created with such printer in a few seconds. When the layer is finished, it's moved up and the next layer is started to be worked on. CLIP technology balances light and oxygen to eliminate the mechanical steps and layers that are the standard DLP process step and allow the production of commercial quality objects at high speed.
This invention provides digital dental devices using computer-aided 3D printing methods as mentioned above. In particular, it is related to designing and manufacturing two or multiple layered dental devices or dental prostheses, such as partial, full dentures or other prosthetic devices, specifically, printing partial, full dentures, surgical guides, nightguards, flippers, splints, orthodontic devices, aligners, retainers, crowns, bridges, partial or full denture bases using computer aided design and printing methods.
Dental devices, specifically for example, denture base and denture tooth should exhibit certain desirable physical characteristics to be suitable for use and offer desirable benefits to patients. They should be dimensional stable for effective functioning, sufficient strength to withstand masticating stresses and resistant to abrasion and chipping during use. They also should be durable and stable to solvents, foods, water, cold and hot and maintain esthetics without discoloration. In addition, they should be esthetics to mimic natural dentition and gum with esthetically acceptable color, i.e., close to that of natural dentition and gum. The denture base and denture tooth should not wear or deform out of occlusion, and denture base should be capable of being bonded firmly to artificial teeth. They should also be adjustable to ordinary means of physical shaping, grinding, and polishing. Denture base and denture tooth materials should be stable without discoloration and provide consistent handling properties during their shelf life. Denture fabricated from denture base and denture tooth materials should provide function, comfort and fit to the patients. It is desirable that denture base materials are compatible with hard and soft mucosal tissues. So it is desirable that denture base contains at least two different materials with different physical and mechanical properties. It is preferable that denture can be easily adjustable to provide better retention, better occlusal contact and better fit so as to provide better function, comfort and performance for patient. It is also preferable that denture can be locally adjustable while other parts remain unchanged.
Typically, denture bases are methacrylate-based acrylics, thermoplastic based or light curable resin based. Most common denture tooth materials are also methacrylate-based acrylics. In general, methacrylate-based acrylics denture bases and teeth are made out of dough from the blending of PMMA or modified PMMA polymer powders with MMA or modified MMA liquids. Denture teeth are commonly made in a tooth manufacturer. Dental lab typically uses denture teeth and denture base material from manufacturer to make denture for patient. The initial step(s) commonly used in the making a denture by making a final impression of a patient's mouth. A cast (or record base) is made of the final impression of a patient's mouth. Typically the cast is made of plaster. Then wax is shaped into the form of a denture base on the cast of the patient's mouth and artificial teeth are positioned into the denture base shaped wax. The denture base shaped wax with the artificial denture teeth is then positioned in an articulator. The artificial teeth in the denture base shaped wax are then articulated. The articulated denture base shaped wax with the artificial teeth is then positioned in a flask. The volume of the flask is filled with hardenable investment material, such as plaster. After the investment material hardens the wax is eliminated, for example by heating the flask in boiling water, leaving the artificial teeth supported by the investment material and a denture base shaped mold cavity within the investment material. After a thorough cleansing of the mold cavity, a denture base material is introduced into the mold cavity. The denture base material then hardens to form a denture. The process to make a denture is long, time-consuming and labor intensive.
Preparation of full and partial dentures typically requires several dental office visits by each patient. The visits include labor intensive processes such as the construction of the base-plate and occlusion rims, wax try-in, invest the wax-up, wax removal and compression packing or pouring of denture base acrylic as described early. This traditional method typically resulted in a denture base containing homogeneous denture base material, which supported artificial denture teeth. A method of using light polymerizable wax like material (Eclipse system sold by Dentsply International) reduces the dental office and laboratory visits and the labor involved in making the denture, which provides a process for making a denture, comprising: articulating artificial teeth while supported by polymerizable material, whereby a denture comprising said artificial teeth is provided without forming a mold for making tooth setup volume of a denture base. The process is completed without forming wax and without applying inorganic plaster to the artificial teeth. Multiple layers of denture base materials are possible and are included in the denture base by this method.
Most recently, 3D printing systems have been using to make denture base and denture. Various 3D printing materials are used for 3D printing to make denture base and denture. Using acquired digital data, a 3D printer prints materials to form final denture with denture base and denture teeth made from different materials. A 3D printer may also print material to form desired denture base, where commercially available artificial denture teeth are subsequently placed into printed cavities and bonded to this denture base. Separately, some denture teeth are also printed by a 3D printer and used to place into printed cavities and bonding to the printed denture base. Dentca's 3D Denture Base System scans the impression and builds denture base layer by layer using a stereolithographic laser printer and then bonds plastic teeth and final cures in a light chamber. FDM 3D printing method prints a denture using FDM printer with scanned or CAD data, which extrudes and deposits molten thermoplastic in layers to build denture from bottom up. Each layer of molten thermoplastic material is deposited on top of previous one and flattened slightly by the extrusion head. The layers are fused together to form final denture base.
Even though current 3D printing methods are very promising, there are still no consistently reliable 3D printing methods and materials to replace the current proven and established methods and materials for denture fabrications by dental laboratory technicians. Conventional denture fabrication process incorporates several steps to ensure the accuracy and functionality of each denture. Nevertheless, some of 3D printing methods required complicated process to obtain digital data. The fabricated denture may not fit in patient's mouth and teeth may not occlude correctly, additional adjustment or reline is needed that can be labor intensive and painful process. Unstable bites on the denture will result in a poor fit. Denture may need to be remade that cost time, money and delay the patient care. Excessive grinding of teeth and denture base may be needed to achieve desired occlusion, which will result in the loss of esthetics of both fabricated denture base and artificial denture teeth and require additional finishing and polishing. It also faces the potential of grinding away more wear resistant enamel layers which commonly existed in some of artificial denture teeth and exposed the less wear resistant dentin layer. In order to avoid above issues, manufacturers and labs often make a try-in denture for the patient. After tried-in, adjusted and confirmed, and then duplicated the tried-in denture by printing or other fabrication methods, which adds additional steps back and requires additional office visits.
It is desirable the denture fabricated can be adjusted during final denture try-in to obtain desirable occlusion without the need of excessive of remaking, grinding, finishing and polishing. A denture fabricated where artificial denture teeth can be adjusted is highly desirable, which can avoid the need of additional tried-in step. It is also desirable the denture fabricated can be comfortable fit perfectly into oral cavity with rigid area to support artificial denture teeth and soft or relatively flexible contact surface to mucosal area for comfort and fit. Typically, denture bases are PMMA based acrylics. However, PMMA and MMA based denture bases have the disadvantage of being subject to brittle fracture due to the nature of PMMA. Rubber impact modified PMMA acrylics were used to improve their fracture toughness and impact strength. Full denture is typically formed from a rigid material since it is needed to support the artificial teeth chewing function without any movement during action. Flexible partial dentures, typically made of flexible thermoplastics, such as Nylon 12, acetal resin, etc. are being commonly used for patients, which provide comfort due to their compliance and flexibility. The use of clasps enables to stabilize the artificial denture teeth in place. The resilience and flexibility of these denture bases are limited due to the need to support artificial denture teeth. Significantly improved resiliency of tissue contact surface is desirable without compromising the artificial denture teeth stability during mastication. It is desirable to have a denture that provides a rigid ridge to support artificial denture teeth in position and resilient and flexible contact layer/area to patient's soft mucosal area for comfort and fit, which is more compatible to patient's oral cavity containing rigid ridge area and soft mucosal area. It is also desirable to have a partial denture that provides a rigid ridge to support artificial denture teeth in position, toughening clasps to stabilize the partial denture in place, and resilient and flexible contact layer/area to patient's soft mucosal area for comfort and fit, which is more compatible to patient's oral cavity containing remaining teeth, rigid ridge area and soft mucosal area. Common practice to improve the patient's comfort and fit is to reline a denture with a soft reline material, which requires additional labor intensive step. It is desirable to provide an integrated denture incorporating a soft layer onto rigid denture base or having two or more areas that offer different performances including a tooth adjustable area. In addition, it is desirable that the contact surface of denture to mucosal area can be adjusted easily to get better fit. It is also desirable that the contact surface of denture to mucosal area can be adjusted and re-adjusted as needed, such as the need due to the ridge resorption over time. An adjustable polymer layer or a shape memory polymer is especially desirable to be used here. When digital intraoral scan is used for the fabrication of denture or denture base, a digital designed tissue side of denture may not perfectly fit to the oral cavity of the patient due to intraoral scanning involving soft tissues and an adjustable polymer layer or a shape memory polymer layer at tissue side allows the denture to be easily adjusted to fit the oral cavity of the patient to get the best fit and comfort. It is also desirable to have a denture, where limited tooth adjustment can be easily achieved. Denture base material around denture teeth can be easily adjusted at elevated temperature or other conditions is preferred.
Even though this invention referred mainly to denture, denture base and teeth, the printing methods and materials of this invention are not limited to the printing of denture, denture teeth or denture base, they can be used to print various dental devices. Their shades can be formed from clear to highly pigmented shade. For example, a multiple layered nightguard can be printed, where the hard and wear resistant top surface layer can effectively withstand wearing and grinding while flexible or resilient side or not occlusal contact part in nightguard can provide comfort, retention and easy insertion and easy removal for the patient. The denture base or denture tooth materials mentioned in this invention can be easily referred as dental materials, such as restorative materials, night guard materials, retainer materials, or aligner materials, etc.
Leyden et al., U.S. Pat. Nos. 6,660,209 and 6,270,335 disclose an ink-jet printing method using commercial print heads having multiple orifices (jets) to selectively fire droplets of hot melt, radiation-curable material onto a substrate. Each orifice can be equipped with a piezoelectric element that causes a pressure wave to propagate through the material when electric current is applied. The print head moves along a scan path selectively depositing the flowable material onto the substrate. In a subsequent step, light radiation is used to cure the material.
Yamane et al., U.S. Pat. No. 5,059,266 discloses an ink-jetting method, whereby a photosetting or thermosetting resin is jetted along a flight passage of the material to a stage to thereby laminate the material on the stage, changing at least one of a jetting direction of the material along the flight passage and a jetting amount of the material, thereby controlling a jetting operation of the material, and exposing the laminated material to light to cure the material, thereby forming the article.
Bredt et al., U.S. Pat. No. 5,902,441 describes another ink-jet printing method, which involves applying a layer of powder particles containing an activatable adhesive onto a flat surface that can be indexed downward. The ink-jet printer introduces an activating fluid onto to the layer of particles in a predetermined pattern. The fluid activates the adhesive in the mixture, causing the particles to adhere together in an essentially solid layer. After the first cross-sectional portion of the article is formed, the movable surface can be indexed downward. Successive layers of the mixture of particles are applied in the same manner to form the desired article.
Oriakhi et al. discloses in U.S. Patent Application Publication No. US 2005/0082710 an ink-jet printing method, wherein a particulate blend of reactive glass ionomer particulates, cross-linkable polyacid particulates including polyvinyl pyrrolidone-co-polyacrylic acid, and nanocomposites is spread in a fabrication bin. An ink-jet printer applies an aqueous phase binder onto a predetermined area of the particulate blend to form hydrated cement. A glass-ionomer chemical reaction causes the hydrated cement to harden.
Kapserchik et al. discloses in U.S. Patent Application Publication No. US 2004/0094058 an ink-jet printing system using acid-base cements. Layers of powder particulate are deposited on a flat surface. The powders include a base such as a metal oxide or an aluminosilicate glass, a polymeric acid or other acid. The ink-jet printer dispenses an aqueous binder. The basic powder interacts with the acid in the presence of water, causing the formation of an ionically cross-linked hydrogel salt. Formation of the cross-linked hydrogel causes setting of the mixture.
More particularly, ink-jet printing methods for making three-dimensional dental products have been developed and are described in the patent literature. For example, Moszner et al., U.S. Pat. No. 6,939,489 discloses a process for fabricating three-dimensional dental form pieces for dental restoration and replacement parts using three-dimensional plotting technology. The object is produced in a layered manner by the cutting away of micro drops or micro cords discharged from nozzles in the three-dimensional plotter. The discharged material can be hardened by a variety of mechanisms depending upon the type of material used. This includes cooling of melted material, polycondensation, polyaddition, or thermal-curing, and light radiation. In the '489 Patent, the three-dimensional plotting technology is described as being different than conventional rapid prototyping (selective laser sintering, 3D printing, and stereolithography).
Rheinberger et al., U.S. Pat. No. 7,189,344 discloses a process for producing three-dimensional dental restorative parts, such as full or partial dental prosthesis, using ink-jet printers that are used in the ink-jet printing methods developed by MIT as described above. The process involves spraying a polymerizable material onto a base support in a layer-by-layer manner. Each layer of material is polymerized by a light source prior to the application of the next layer. The polymerizable material is described as being wax-like having up to 70% by weight of at least one of a polymerizable monomer and oligomer; from 0.01 to 10% by weight of a polymerization initiator; and at least 20% by weight of a mixture having a selected one of a wax-like and flowable monomer and a color pigment.
Feenstra, U.S. Pat. Nos. 6,921,500 and 6,955,776 disclose an ink-jet printing process for making dental elements such as crowns using a liquid binder and powder bed. The element is produced by applying successive layers of powder and discharging the liquid binder onto the layers using an ink-jet printer. The binder preferably includes nanomeric, inorganic solid particles having polymerizable and/or polycondensable organic groups at their surface. After the binder has been applied to the last layer of powder, any excess, unbound powder is removed. Then, the powdered layers are sintered by heating to a temperature in the range of about 400 to 800° C. The sintering step is performed so that only necks between the powder particles are formed. The resulting sintered dental element is infiltrated by a second phase material, such as glass-ceramic or polymer, which melts at a lower temperature than the material of the dental element. This reduces the porosity of the dental element.
Bordkin et al., U.S. Pat. No. 6,322,728 discloses an ink-jet printing process for making dental restorations by printing a binder into layers of powder. The process involves depositing a layer of ceramic or composite powder material onto a powder bed. The design of the restoration is based on a CAD representation. A binding material is applied onto the ceramic or composite layer. This application of powder/binder material is repeated several times to produce the desired shape of the restoration. After the layering process is completed, the structure is cured to further promote binding of the particles.
The present invention provides novel high strength/toughness, resilient or high toughness liquid resin/composite systems for fabricating three-dimensional dental devices using the Inkjet, Digital Light Processor (DLP) projectors or stereolithography. This invention can also use many commercially available materials, such as polymerizable resins, thermoplastic materials, shape memory polymers, etc., their combinations and their combinations with liquid resin/composite systems of this invention and several early inventions of present inventor(s) for fabricating three-dimensional dental devices using the Inkjet, FDM, DLP, SLS, SLA or their combinations. Although the Inkjet, DLP or SLA method and high strength/toughness, resilient or high toughness materials are described primarily herein as being used to make a layered dental prosthesis, such as splint, aligner, full and partial denture, denture base and artificial teeth, etc., it should be understood that this is for illustration purposes only. The inkjet, DLP method or SLA method using high strength/toughness, resilient or high toughness materials can be used to make any dental device such as, for example, artificial teeth, dentures, orthodontics, splints, veneers, inlays, onlays, copings, frame patterns, retainers, aligners, flippers, night guards, sport guards, crowns and bridges and the like. We have provided a general description of these methods using high strength/toughness, resilient or high toughness material systems as follows. (A more detailed description of the methods and high strength/toughness, resilient, or high toughness materials used to make the dental devices is set forth below.)
In this method, a polymerizable liquid resin material or heated resin material as a liquid is loaded into a resin bath of a 3D printer based on a DLP method, SLA method or a combination of DLP and SLA. In the case of using DLP method, it builds 3D objects by projecting sequential voxel planes into liquid resin (or heated liquid resin), which then polymerizes it to solid. Successive layers of polymerized material are added in this manner until the device is completely fabricated. Multiple light (or laser) sources may be used with these methods. Once first object was built with successive layers of first polymerized material, subsequent successive layers of second polymerized material may be added to first polymerized object by these methods, which typically require the projecting sequential voxel planes into liquid resin (or heated liquid resin) from top down or tilted angle. Similarly, additional polymerized materials can be built on above objects having two or more polymerized materials to form final two or more layered device. Then the device, for example, a denture, is washed, finished and fully final cured as needed. The fully cured and polished denture is now ready to be used by the patient. In the case of two layered aligner or splint, two clear vats of polymerizable liquid resin materials might be used and built up the devices layer by layer. Moreover, two or more parts may be printed out separately with different materials and then bonded them together to form final objects (or dental devices). Printed out different material layers (parts) may also be finally cured together to form layered objects (or dental devices).

Three dimensional fabricating material systems and methods for producing layered dental products


A phase locked loop can reduce a locking time, thereby efficiently reducing power in a locking operation. The phase locked loop includes a phase detector, a control voltage generator, a voltage controlled oscillator and a start-up driver. The phase detector detects a phase difference between a reference clock and a feedback clock to generate a detection signal corresponding to the detected phase difference. The control voltage generator generates a control voltage having a voltage level corresponding to the detection signal. The voltage controlled oscillator generates an internal clock having a frequency corresponding to a voltage level of the control voltage. The start-up driver drives a control voltage terminal to a predefined start-up level in response to a start-up level multiplex signal corresponding to a frequency of the reference clock prior to activation of the voltage controlled oscillator.

The present invention relates to a semiconductor device, and more particularly to a phase locked loop (PLL), which can ensure a fast locking time, and a method for operating the same.
In semiconductor devices such as double data rate (DDR) synchronous dynamic random access memory (SDRAM), an external clock is used as a reference to match operation timings. However, a clock skew may occur in the external clock due to the delay in clock/data path of internal circuits. In order to compensate the clock skew, a clock synchronization circuit is provided within the semiconductor device. Examples of the clock synchronization circuit include a phase locked loop (PLL) and a delay locked loop (DLL). The semiconductor device transmits/receives signals to/from external devices by using an internal clock outputted from the clock synchronization circuit.
The PLL having a frequency multiplication function is mainly used when the frequency of the external clock is different from the frequency of the internal clock, and the DLL is mainly used when the frequency of the external clock is equal to the frequency of the internal clock. The configuration of the PLL is basically similar to that of the DLL. The PLL uses a voltage controlled oscillator (VCO) to generate the internal clock, while the DLL uses a voltage controlled delay line (VCDL).
Compared with the DLL, the PLL occupies a large chip area and is difficult to design, but it can generate various clocks through frequency synthesis and can easily achieve a clock data recovery (CDR). Therefore, the PLL is used in a variety of applications, e.g., communications, wireless systems, digital circuits, etc. As the operating speed of the chip is increasing, the PLL is essential to designing high-speed semiconductor devices with high operating frequency. It is expected that the application fields of the PLL will be widely expanded with rapid development of semiconductor device design technology.
FIG. 1 is a block diagram of a conventional PLL.
Referring to FIG. 1, the PLL includes a phase detector 110, a control voltage generator 130, a voltage control oscillator (VCO) 150. The phase detector 110 detects a phase difference between a reference clock CLK_REF and a feedback clock CLK_FED to generate detection signals DET_UP and DET_DN corresponding to the detected phase difference. The control voltage generator 130 receives the detection signals DET_UP and DET_DN to generate a control voltage V_CTR having a voltage level corresponding to the detection signals DET_UP and DET_DN. The VCO 150 generates an internal clock CLK_INN having a frequency corresponding to the control voltage V_CTR. A frequency divider 170 may be further included which divides the frequency of the internal clock CLK_INN to generate the feedback clock CLK_FED.
The phase detector 110 generates the up detection signal DET_UP and the down detection signal DET_DN according to the phase difference between the reference clock CLK_REF and the feedback clock CLK_FED. The up detection signal DET_UP is a pulse signal enabled when the phase of the feedback signal CLK_FED lags behind the phase of the reference clock CLK_REF, and it has a pulse width corresponding to the phase difference between the feedback signal CLK_FED and the reference clock CLK_REF. The down detection signal DET_DN is a pulse signal enabled when the phase of the feedback signal CLK_FED leads the phase of the reference clock CLK_REF, and it has a pulse width corresponding to the phase difference between the feedback signal CLK_FED and the reference clock CLK_REF.
The control voltage generator 130 includes a charge pump 132 and a loop filter 134. The charge pump 132 controls a current to be supplied to the loop filter 134 according to the pulse width of the up detection signal DET_UP and the down detection signal DET_DN. The loop filter 134 generates the control voltage V_CTR by charging or discharging the supplied current.
The VCO 150 generates an internal clock CLK_INN having a frequency corresponding to a voltage level of the control voltage V_CTR. For example, as the voltage level of the control voltage V_CTR becomes higher, the frequency of the internal clock CLK_INN becomes higher. As the voltage level of the control voltage V_CTR becomes lower, the frequency of the internal clock CLK_INN becomes lower.
The frequency divider 170 generates the feedback clock CLK_FED having a frequency lower than the internal clock CLK_INN in order to use a crystal oscillator as a reference frequency source. The crystal oscillator can maintain the reference clock CLK_REF at the correct frequency even in a change of surroundings. The phase detector 110 compares the feedback clock CLK_FED of a low frequency with the reference clock CLK_REF of a low frequency.
The PLL generates the internal clock CLK_INN having a desired frequency by repeating the locking operation until the frequency of the reference clock CLK_REF is equal to that of the feedback clock CLK_FED. The term "locking" means that the internal clock CLK_INN has a desired target frequency.
FIG. 2 is a block diagram of the phase detector 110 illustrated in FIG. 1.
Referring to FIG. 2, the phase detector 110 includes a first D flip-flop 112, a second D flip-flop 114, and a logic gate AND1. The first D flip-flop 112 is configured to generate the up detection signal DET_UP in response to the reference clock CLK_REF. The second D flip-flop 114 is configured to generate the down detection signal DET_DN in response to the feedback clock CLK_FED. The logic gate AND1 is configured to receive the up detection signal DET_UP and the down detection signal DET_DN to generate a reset signal CTR_RST resetting the first and second D flip-flops 112 and 114.
The phase detector 110 generates the up detection signal DET_UP of a logic high level when the reference clock CLK_REF is at a high level, and generates the down detection signal DET_DN of a logic high level when the feedback clock CLK_FED is at a logic high level. The phase detector 110 activates the reset signal CTR_RST to reset the first and second D flip-flops 112 and 14 when the reference clock CLK_REF and the feedback clock CLK_FED are all at a logic high level.
Consequently, when the phase of the reference clock CLK_REF leads that of the feedback clock CLK_FED, the phase detector 110 generates the up detection signal DET_UP having a pulse width corresponding to the phase difference between the reference clock CLK_REF and the feedback clock CLK_FED. When the phase of the feedback clock CLK_FED leads that of the reference clock CLK_REF, the phase detector 110 generates the down detection signal DET_DN having a pulse width corresponding to the phase difference between the reference clock CLK_REF and the feedback clock CLK_FED.
Since the circuit configurations of the first and second D flip-flops 112 and 114 are well known, their detailed description is omitted for conciseness.
FIG. 3 is a circuit diagram of the VCO 150 illustrated in FIG. 1.
Referring to FIG. 3, the VCO 150 includes a plurality of PMOS transistors 152, a plurality of NMOS transistors 154, and a plurality of inverters 156. Each of the inverters has unit delay time according to a voltage level of the control voltage V_CTR. When the voltage level of the control voltage V_CTR increases, a large amount of current is supplied to the inverters of the VCO 150. Therefore, the delay time of each of the inverters becomes short and the VCO 150 generates the internal clock CLK_INN of a high frequency. On the other hand, when the voltage level of the control voltage V_CTR decreases, a small amount of current is supplied to the inverters. Therefore, the delay time of each of the inverters becomes long and the VCO 150 generates the internal clock CLK_INN of a low frequency.
The control voltage (V_CTR) terminal of the VCO 150 will be described below.
In the VCO 150, the voltage level of the control voltage V_CTR is made to a logic low level before the locking operation. This prevents undesired current consumption caused by unnecessary operations of the VCO 150 before the PLL operates.
In other words, since the control voltage V_CTR is inputted to gates of the plurality of NMOS transistors 154, the control voltage V_CTR is made to a logic low level before the PLL operates. If the control voltage V_CTR is inputted to the plurality of PMOS transistors 152, the control voltage V_CTR is made to a logic high level before the PLL operates.
The PLL of FIG. 3 performs the locking operation to increase the control voltage V_CTR of a logic low level up to a voltage level at which the internal clock CLK_INN of a desired target frequency can be generated. The time necessary to generate the control voltage V_CTR for generating the internal clock CLK_INN of the desired target frequency is defined as a locking time.
To meet the requirements of high-speed operation of semiconductor devices, it is necessary to rapidly generate the internal clock CLK_INN of a desired frequency at a fast speed by reducing the locking time. Thus, there is a need for techniques that can reduce the locking time.

Phase locked loop and method for operating the same


Environmentally degradable molded or extruded articles comprising a blend of polyhydroxyalkanoate copolymer and an environmentally degradable thermoplastic polymer or copolymer are disclosed. Such compositions provide annealing cycle times to form molded or extruded articles that are less than annealing cycle times to form a molded or extruded article lacking the environmentally degradable thermoplastic polymer or copolymer.

This invention relates to the need for developing new plastic materials that can be used in applications where biodegradability, compostability or biocompatibility are among primary desirable features of such applications. There have been many attempts to make degradable articles. However, because of costs, the difficulty in processing, and end-use properties, there has been little commercial success. Many compositions that have excellent degradability have only limited processability. Conversely, compositions which are more easily processable have reduced degradability.
An example of a molded or extruded article that accumulates in the environment is a plastic tampon applicator. Paper tampon applicators are considered environmentally friendly in that they readily disintegrate in a sewage system and/or can be disposed of through aerobic, anaerobic, or natural degradation processes. However, paper tampon articles are not most favored among females due to pledget insertion difficulties associated with their use. Certain female consumers prefer plastic tampon applicators because the plastic applicators are easier to insert, however, most plastic tampon applicators are made from polymeric materials that are not biodegradable and that do not readily soften or break-up into smaller fragments for decomposition in a sewage system, resulting in increased environmental concerns.
An applicator made from water soluble polymers such as polyvinyl alcohol suffers from moisture sensitivity, stability, odor, or stickiness. Further, a plastic tampon applicator constructed from water soluble polymers, such as polyvinyl alcohol and polyethylene oxide, does not provide enough in-use integrity during insertion and tends to stick to sewer pipes after flushing which can lead to clogging of toilet systems and/or drain pipes.
Polyhydroxyalkanoates (PHAs) are thermoplastic polymers desirable for use in molded or extruded articles particularly due to their biodegradability. U.S. Pat. No. 5,498,692, issued Mar. 12, 1996 to Noda, and U.S. Pat. No. 5,502,116, issued Mar. 26, 1996 to Noda, relate to molded articles comprising PHAs. Molded articles from such PHAs remain substantially tacky after they are cooled down from the melt, and remain as such until sufficient crystallinity sets in, particularly with PHA copolymers levels above 10 wt %. Residual tack typically can lead to material sticking to itself or to the processing equipment, or both, and thereby can restrict the speed at which a polymeric product is produced or prevent the product from being collected in a form of suitable quality. A poly(3-hydroxybutyrate-co-3-hydroxyvalerate) product commercialized under the name BIOPOL® suffers from hardness, brittleness, and from having very slow crystallization kinetics. Similarly, U.S. Pat. No. 5,292,860 to Shiotani lacks teachings regarding compositions having short cycle times in the manufacturing process for molded or extruded articles.
Consequently, there is a need for melt processable compositions of environmentally degradable polymers for use in molded or extruded articles where the polymers have economically viable annealing cycle times. Moreover, the compositions should be suitable for use in conventional processing equipment, and resultant molded or extruded articles should meet consumer acceptability for their structural integrity and aesthetic characteristics of smoothness, flexibility, reduced stickiness, stability, and the like.

Molded or extruded articles comprising polyhydroxyalkanoate copolymer and an environmentally degradable thermoplastic polymer


A multiplying system based on the Booth's algorithm, comprises a Booth's decoder having a first input receiving a multiplier "Y" and a second input receiving a mode signal designating either a first multiplication of "X.times.Y" (where "X" is a multiplicand) or a second multiplication of "-X.times.Y". The Booth's decoder generates a Booth's decoded value and a sign selection signal to a partial product generation circuit which also receives the multiplicand "X", so that the partial product generation circuit generates either a first partial product of "X.times.Y" or a second partial product of "-X.times.Y" in accordance with the sign selection signal. An output of the partial product generation circuit is summed by a partial product summing circuit, and an output of the partial product summing circuit is added to a value "A" stored in an output register by an arithmetic unit. Thus, the accumulating multiplication "A=A.+-.X.times.Y" can be executed in the same hardware without using a circuit for sign-inverting the output of the partial product summing circuit.

1. Field of the Invention
The present invention relates to a multiplying system, and more specifically to a multiplying system for preforming an accumulating multiplication expressed by "A=A.+-.X.times.Y" where "A", "X" and "Y" are in the form of two's complement.
2. Description of Related Art
Conventionally, when the accumulating multiplication "A=A.+-.X.times.Y" where "A", "X" and "Y" are in the form of two's complement) is performed, a multiplication of "P=X.times.Y" is first executed. For this purpose, the multiplier "Y" is supplied to a Booth's decoder, and an output of the Booth's decoder is supplied together with the multiplicand "X" to a partial product generation circuit, so that a partial product is generated. The generated partial product is summed in a partial product summing circuit, so that "P" (=X.times.Y) is obtained. Thereafter, the calculation of "A.+-.P" is performed using an arithmetic unit. For this purpose, an output of the partial product summing circuit is connected directly to one input of a selector and also through a sign inverting circuit to the other input of the selector. An output of the selector is connected to one input of the arithmetic unit, which in turn has its other input connected to a register holding the value "A". Thus, when the calculation of "A-P" is performed, the selector supplies an output of the sign inverting circuit to the arithmetic unit, and when the calculation of "A+P" is performed, the selector supplies the output of the partial product summing circuit to the arithmetic unit.
In the above mentioned multiplying system, when the accumulating multiplication "A=A-X.times.Y" is to be executed, a circuit for inverting the sign of the result of multiplication between "X" and "Y" is required. Therefore, the amount of required hardware is increased, and in addition, the operation speed drops.

Multiplying system based on the Booth's algorithm and generating a positive or negative product in response to a mode signal


A radio receiver for receiving an existing analog broadcast and a terrestrial digital radio broadcast transmitting digital signals, the receiver having a plurality of antennas 11a, 11b, and composed of a diversity receiver 12 for receiving terrestrial digital radio broadcasts by antenna switching; and a controller 21 for disabling diversity reception when the number of receivable broadcasting stations acquired by station selection operation is a predetermined number or more.

In a vehicle radio receiver included in radio receivers, to reduce the effects of the fading caused by the movement of a vehicle and secure the ability of the radio to receive analog broadcasting, diversity reception that selects an antenna which is in the best receiving condition from among a plurality of antennas is in widespread use.
However, the main reasons of the noise and the distortion of a received sound include multipath interference. The multipath interference is caused by the mutual interference of a plurality of signals propagating through different routes from a transmitter of a broadcasting station to reach an antenna. For example, a direct wave directly reaching thereto from a transmission antenna and some reflected waves are superimposed on each other, and the phase differences therebetween and the like extremely reduce the signal intensity of the received signal. Depending on the differences of path length between the received waves, if the difference of path length is small, a multipath interference wave having a short delay time reaches the antenna, and if the difference of path length is large, a multipath interference wave having a long delay time reaches thereto.
The level of multipath interference varies depending on geographical and building conditions. Particularly in an urban area where high-rise buildings stand side by side along both sides of a road, a broadcast wave propagates along a road, and is reflected by high-rise buildings to generate reflected waves having a short delay time. Therefore, when a large number of multistory buildings stand, a broadcast wave contains a lot of received signals with a short delay time.
Since a vehicle moves in such a changing radio wave environment during the running thereof, there may easily occur fluctuations in the electric field strength more frequently in a short time. Therefore, an antenna switching for selecting an antenna existing in the best receiving condition may easily occur frequently.
On the other hand, in recent years, terrestrial digital radio broadcasting is popularized, which simultaneously transmits analog and digital signals using the frequency of existing AM/FM analog broadcasting. In North America, about 1700 or more broadcasting stations have started the hybrid broadcasting by an IBOC (In-Band On-Channel) method, or are getting ready for sending. The hybrid broadcasting can use the same frequency as that of the existing analog broadcasting, different from the terrestrial digital radio broadcasting of Japan, and thus a broadcasting station need not afresh prepare a frequency for digital broadcasting. A radio receiver using a conventional analog method can receive existing broadcasting, and at the same time a hybrid radio receiver capable of receiving digital broadcasting can also receive digital one.
Incidentally, in a hybrid radio receiver capable of receiving the hybrid broadcasting using the above IBOC method, it is known that in performing antenna switching while receiving digital broadcasting, "out-of-synchronization" in digital demodulation occurs by the phase difference between the switched antennas. Particularly in an urban area, there frequently easily occurs the "out-of-synchronization" by the antenna switching.
In order to avoid the reduction of the ability for receiving the hybrid broadcasting using the above IBOC method due to the "out-of-synchronization," an IBOC broadcasting receiver in a related art is known, which controls diversity reception to be disabled when it is judged that an IBOC broadcast wave exists based on a demodulation result (for example, see Patent Document 1).


The present invention is directed to an easily-digestible pet chew for promoting oral health and preventing malodorous breath in animals. The pet chew is formed with ingredients selected to promote mastication and ease digestibility, and additionally includes baking soda and abrasives to reduce tartar and plaque and eliminate malodorous breath. The pet chew has a soft, malleable texture that is easily chewed by animals and easily digested once swallowed. The pet chew also includes a white coloring interspersed with colored crystals formed in a bone-like shape that appeals to both animals and their owners.

(1) Technical Field
The present invention relates to the field of edible pet chews, and specifically to pet chews that are easy to digest and have properties that improve oral health and eliminate malodorous breath in animals.
(2) Background
It is well known that household pets such as dogs and cats often suffer from poor oral health. This problem also manifests itself with bad breath, which is particularly unpleasant in dogs. Many edible pet chews have been developed to promote fresh breath in dogs and reduce tartar buildup. However, edible pet chews are often hard, brittle, and difficult to digest. Dogs chewing these pet chews usually break them into pieces which are sharp and can cause damage to the digestive tract once swallowed. Other times, the chews are swallowed whole, where they can easily become lodged in a dog's throat and cause choking, or become lodged in a dog's digestive tract, requiring surgery to remove and sometimes leading to death. One recent test demonstrated that a typical hard pet chew dissolved only 34.6% in a digestive simulation test over the better part of a day.
Additionally, most edible pet chews directed to promoting oral health and eliminating malodorous breath are ineffective due to the hardness of the chew. A typical pet chew operates to remove plaque and tartar from a dog's teeth by the chewing action whereby the abrasive texture of the pet chew scrapes the plaque and tartar from the teeth. In a typical hard, brittle dog chew, this chewing action is brief, as the dog will usually quickly break the pet chew apart and swallow the pieces or even swallow the pet chew whole without chewing at all. Therefore, the oral health advantages of these dog chews are negated. The ingredients included to prevent or eliminate malodorous breath suffer from the same limitation, in that the shorter time period the dog chew is in the dog's mouth, the less effective the ingredients are at eliminating the bacteria and odor that leads to bad breath.
Additionally, the ingredients used in existing pet chews to combat malodorous breath are numerous but still limited by their compatibility with other pet chew ingredients and the processing used to form most pet chews. One of the most effective treatments of malodorous breath is baking soda, otherwise known as sodium bicarbonate. However, its reactive nature has prevented it from being implemented into the pet chews thus far.
Thus, what is needed is a pet chew with a texture that promotes mastication, is easily digested, and contains effective ingredients to promote oral health and prevent malodorous breath in animals.

Easily-digestible pet chew that promotes oral health and prevents malodorous breath in animals, and method of making thereof