(1) Field of the Invention
This invention relates to a novel method for processing a picture to reproduce the picture with improved visibility on a color television receiver, and to a picture processor therefor.
(2) Description of the Related Art
Reference is first made to FIG. 3 which is a simplified block diagram of a transmission system for color television pictures. In a television camera 21, a multicolored light is received from an object through a lens 22 and the color of the object is separated into the three primary colors, i.e., red (R) light, green (G) light, and blue (B) light by use of a dichroic mirror unit 23. From these colors of light, primary color signals E.sub.R,E.sub.G,E.sub.B are then produced by image orthicon camera tubes 21R,21G,21B, respectively. A luminance signal E.sub.Y, representative of the brightness of the picture, and color signals having information as to hue and saturation values are reproduced from the primary color signals by a matrix circuit 24 are then transmitted. The color signals which provide the primary color signals E.sub.R,E.sub.G,E.sub.B when combined with the luminance signal E.sub.Y are color difference signals E.sub.R -E.sub.y,E.sub.G -E.sub.Y, E.sub.B -E.sub.Y. When such color difference signals are transmitted, the luminance signal E.sub.Y is added in the following manner at the reception side, thereby making it possible to reproduce the original primary colors. EQU (E.sub.R -E.sub.Y)+E.sub.Y =E.sub.R EQU (E.sub.G -E.sub.Y)+E.sub.Y =E.sub.G EQU (E.sub.B -E.sub.Y)+E.sub.Y =E.sub.B
As depicted in FIG. 4, the signals thus transmitted are received by an antenna 25. The desired channel is selected by a tuning circuit 26, so that the signals are amplified and converted into intermediate frequency signals. Video intermediate frequency (IF) signals which have been amplified at an intermediate frequency (IF) amplifier 27 are converted into video signals at a video signal detector 28. After amplification of the video signals at a video signal amplifier 29, the resulting signals are fed to a color picture tube 1. By electron beam scanning, a complete picture is formed from a series of video signals. Here, synchronizing signals transmitted along with the video signals are separated at a synchronous circuit 31 to control a horizontal and vertical deflection circuit 32, whereby the frequency and phase of the electron beam scanning are maintained consistent with those at the transmission side.
On the other hand, audio intermediate frequency (IF) signals are converted into audio FM signals at an audio signal detector and FM converter 33. The audio FM signals are converted further into audio signals by an FM detector 34 and a low frequency (LF) amplifier 35 and are then reproduced at a speaker 36.
The video signal amplifier 29 serves to amplify each luminance signal of the color television signals, which have been obtained at the video signal detector 28, to a level sufficient to activate the color picture tube 1. The video signal amplifier 29 is usually constructed of amplification circuits arranged in 3 to 5 stages and various auxiliary circuits.
To reproduce a color picture, the color picture tube 1 has to be fed with primary color signals. There are two types of manners for feeding these signals, i.e., the primary color drive system and the color difference drive system. FIG. 5 is a block diagram showing how primary color signals are produced and then fed to the color picture tube 1 in the primary color drive system. Primary color signals E.sub.R,E.sub.G,E.sub.B are applied at a negative polarity to respective cathodes 37-1,37-2,37-3 of the color picture tube 1, while respective first grids 38-1,38-2,38-3 are fed with a d.c. voltage.
The primary color signals are produced by adding the luminance signal and color difference signals at a matrix circuit 39. The matrix circuit 39 is inputted with the luminance signal E.sub.Y and color difference signals E.sub.R -E.sub.Y,E.sub.G -E.sub.Y,E.sub.B -E.sub.Y and produces as outputs negative primary color signals -E.sub.R,-E.sub.G,-E.sub.B. The negative primary color signals are then fed to the respective cathodes 37-1,37-2,37-3 of the color picture tube 1.
In the color picture tube 1, electron beams controlled by the primary color signals are caused to impinge exactly on color phosphors of red, green and blue colors, respectively, by way of a color sorting system, free of illustration, so that the phosphors are caused to glow to reproduce the color picture. The construction of the color picture tube 1 is illustrated in FIG. 6. The color picture tube 1 is basically constructed of three components, namely, an electron gun 61 for generating and directing electron beams, a shadow mask 62 for causing the electron beams to impinge only on phosphor dots of the designated colors, and a phosphor screen 63 coated precisely with red (R), green (G) and blue (B) phosphor dots in a predetermined pattern. Depending on differences in these components, color picture tubes can be classified into several types. Their details are however omitted herein.
Formation of a picture on a color picture tube is performed by left-to-right scanning (horizontal scanning) and up-to-down scanning (vertical scanning). The picture is successively and downwardly formed on the picture screen from the upper left corner. When the scanning has reached the lower right corner, the scanning returns again to the upper left corner. In this manner, 30 pictures, which are each divided into 525 lines, are formed per second. Accordingly, the horizontal scanning is repeated 15,750 times a second (525 lines.times.30 pictures) while the vertical scanning is repeated 30 times.
However, interlaced scanning is used in actual scanning. As a result, the vertical scanning is repeated 60 times. As illustrated in FIG. 7(a) and 7(b), interlaced scanning is performed by first coarsely scanning at some intervals as indicated by numbers 1, 2, 3 and 4 and then scanning once more between the first scanning lines as indicated by numbers 5, 6 and 7. The scanning of an entire picture is brought to completion by only these two vertical scanning operations. When interlaced scanning is performed, two coarse pictures of 262.5 scanning lines are sent successively to form a picture of 525 scanning lines. It therefore appears as if 60 pictures are sent out, although 30 pictures are actually sent out per second. It is hence possible to obtain pictures of little flicker.
As has been described above, the conventional television receivers have reached a technical level which is satisfactory from the practical viewpoint. It is, however, now strived to improve the dissolution further, for example, by increasing the number of scanning lines to 650 or 700 lines per screen or converting the signal processing circuits into their digital counterparts. In addition, high-definition television receivers have also been developed, as future television receivers, for commercial use.


1. Field of the Invention
This invention relates to cementing plugs for use in cementing casing in a well, and more particularly, to a universal cementing plug having improved wiping and extended wear and which includes a plurality of interchangeable inserts so that the plug may be selectively used as a top or a bottom plug.
2. Description of the Prior Art
In the process of preparing a well for testing and/or production, a casing is positioned in the well and cemented in place. Typically, at the beginning of the cementing job in rotary-drilled wells, the casing and the wellbore are usually filled with drilling mud. In many areas, to reduce contamination on the interface between the mud and cement a bottom plug is released from a plug container and pumped ahead of the cement slurry. Such plugs have wipers of an elastomeric material thereon to wipe the casing of any accumulated mud film so that the mud is pushed ahead of the bottom plug.
When the bottom plug reaches floating equipment such as a float collar or float shoe at the bottom of the casing string, a fluid pressure differential created across the plug ruptures a rubber diaphragm at the top of the plug and allows the cement slurry to proceed down the casing through the plug and floating equipment and then up an annulus space defined between the casing and the wellbore.
When all of the cement has been mixed and pumped into the casing string, a top cementing plug is released from the plug container. The top plug also has wipers of elastomeric material thereon. The function of the top plug is to follow the cement and wipe any accumulated cement film from the inside of the casing. The top plug is also designed to reduce the possibility of any contamination or channeling of the cement slurry with the drilling mud that is used to displace the cement column down the casing and into the annular space between the casing the wellbore. The top cementing plug is typically solid in construction, and the design is such that when it reaches the bottom cementing plug at the float collar or float shoe, the top cementing plug causes a shutoff of fluids being pumped into the casing. This causes a normal pressure rise at the surface and notifies the operator that the cementing job is complete.
The landing of the top plug lessens the possibility of any further displacement of the cement slurry and provides a better quality of cement slurry around the bottom of the casing where a good cement bond to the casing is required.
Currently, two different cementing plugs are used in this cementing operation, one for the top and one for the bottom. The bottom plug has a shearable member, such as the rubber diaphragm previously mentioned, which shears when a specific fluid pressure differential is applied thereto. The top plug is substantially solid. Because each plug requires different construction, separate molds must be used for each of the plugs which increase the costs of manufacturing, and also, the two separate plugs must be kept in inventory. The present invention solves this problem by using a single plug subassembly design which has the same general construction whether it is used as a top plug or a bottom plug. A shearable insert in positioned in one plug so that it may be used as a bottom plug. This shearable member is designed to shear at a predetermined differential pressure thereacross. In one embodiment, the shearable member is a flat disc, and in another embodiment, the shearable member has a relatively thin domed portion. Another insert, which is essentially non-shearable at the pressures in which the plugs are utilized, is positioned in another plug so that it can be used as a top plug. By the use of a single plug subassembly, with separate inserts, the cost of molds of the plugs is decreased, and only one plug must be maintained in inventory along with the different inserts.
Another advantage of the present invention is that the shearable member may be interchangeable with a plurality of shearable members, including, but not limited to, the two embodiments previously described, designed to shear at any one of a selected number of differential pressures as necessary for different well conditions. This is an improvement over the previous design which had essentially one shear pressure.
With prior art cementing plugs, the wiping efficiency of the wipers on the plugs is affected by pumping rate and wear along the casing surface. The cementing plug of the present invention provides an improved wiper design which offers more surface contact, and as the plug is pumped down the casing, wiping efficiency is increased. As a top cup on the plug wears, the pressure is transferred to a bottom cup which prolongs the surface engagement maintaining the wiping, resulting in extended wear.


In subsea offshore well operations, a subsea installation may include hydraulically and also electrically controlled equipment, such as valves which are remotely operated from a platform structure located at the surface of the ocean. Hydraulic and electrical control lines extending from the platform to the subsea installation are desired to be releasably connected to the subsea installation so that if the platform must move to another location or be released from its connection to the subsea station, such release may be readily made. In some instances, such a control line has been associated with tension line means integral therewith so that the line, sometimes called an umbilical line, may be locked at its lower end to the subsea installation.
An example of such an umbilical line construction is shown in my copending application Ser. No. 771,799 owned by a common assignee wherein the umbilical line extends from the subsea installation to a buoyant structure located about 300 feet below the sea surface and the umbilical line continues above the buoyant structure to a floating platform. The buoyant structure is connected with a marine riser system having a lower riser portion and an upper riser portion so that the upper riser portion and the upper portion of the umbilical line can be disconnected at the buoyant structure and the floating platform moved to another location upon such disengagement. The buoyant structure and the lower riser portion are free-standing to permit reengagement of the upper riser portion at a later time. It is desirable that the buoyant structure be securely tethered to the subsea installation so that in the event the lower riser portion should break, the buoyant structure, which exerts an upward tension on the lower riser portion, will not be suddenly released and rapidly travel to the surface and perhaps strike and cause damage to the floating platform normally thereabove.
In prior proposed locking systems for guide line connectors for use in such installations, manually operated locking devices were maintained in locked position by mechanical springs and were unlocked by use of a submarine or by use of go devil means.


The present invention relates to a method for producing an electroluminescent element (may be referred to as an abbreviation of EL) in which a pattern is formed.
EL elements attract attention as spontaneously emitting flat panel display elements in which positive holes and electrons, which have been poured into from opposed electrodes, are combined in a luminous layer to generate energy, and the energy excites fluorescent material in luminous layer to emit light of a color corresponding to the fluorescent material. Among them, an organic thin film EL display using an organic material as a luminescent material has such a high luminous efficiency that high intensity luminescence can be realized even if applied voltage is a little less than 10 V, is possible to emit light with a simple element structure, and is expected to be applied to low-cost simple expression displays such as advertisements and the like in which specific patterns are emitted and displayed.
In the production of a display using such an EL element, patterning on an electrode layer and an organic EL layer is usually put into practice. Methods of EL element patterning include a vapor deposition method of a luminescent material via a shadow mask, a method of separately painting through inkjet, a method of destroying specific luminescent pigment through ultraviolet irradiation, a screen printing method, and others. However, these methods could not provide an EL element being possible to realize all of the high luminous efficiency, the high light takeout efficiency, the simplicity of the production process, and the formation of highly fine patterns.
The present invention has been achieved in order to solve the above-mentioned problems. It is a main object of this invention to provide a method for producing an EL element for realizing the high luminous efficiency, the high light takeout efficiency, the simplicity of the production process, and the formation of highly fine patterns.


1. Field of the Invention
The present invention relates to an image decrypting apparatus, an image encrypting apparatus, and an image decrypting method that decrypt an encrypted image using a decryption key.
2. Description of the Related Art
Leakage of confidential information is a serious problem in the advancement of computerization of the general society and development of a technique that prevents the leakage of the information is desired. For example, as to digital data, a technique has been developed of encrypting data to prevent the content of the data from being viewed when the data is delivered to a third party. The technique is already utilized as a useful means of preventing information leakage.
On the other hand, a technique of preventing information leakage of a printed item printed on a paper medium, etc., has not been fully developed yet and any example thereof is not present. It is also actually said that substantially a half of the information leakage occurs from printed items. Therefore, similarly to the case of digital data, development of a technique of preventing information leakage from printed items is an urgent mission.
Specific examples for which a measure against the information leakage from the printed items is desired include a bill for purchase of merchandise, a statement for a credit card, etc., a clinical chart of a hospital, a report card of a school, and a name list. The present invention is usable as a technique of preventing information leakage by encryption and decryption of important portions of, for example, each of these examples.
Conventionally, a known example that handles encryption of a printed item can be, for example, a technique disclosed in Japanese Patent Application Laid-Open Publication No. 8-179689. According to this '689 publication: an entire original image is divided into a plurality of blocks; images respectively of the divided blocks are rearranged based on a parameter obtained from a password input (encryption key); the image of each of the blocks designated by the parameter are black/white-inversed and mirror-inversed; and, thereby, the original image is encrypted. When the encrypted image is decrypted, a frame for positioning is added to the image in the outer periphery thereof and another password (decryption key) is input. Thereafter, the original image is recovered by performing the encryption in a reverse manner.
Another convention technique can be, for example, a technique of embedding binary data as an image in a printed item, as shown in Japanese Patent Publication No. 2938338. The visualization as an image in this conventional technique is realized by representing the binary data using black-and-white squares each having a designated size and arranging the squares in a matrix. In addition, the printed item is added with a symbol for positioning at a designated position in the matrix such that the position that is visualized as an image can be known in decryption. Using this positioning symbol as the criterion enables shooting of the image using a scanner or a camera and, thereby, decryption of the information embedded.
In the above conventional techniques, a process is performed of decrypting an encrypted image output on an analog medium by printing, etc., into the original image using a reverse procedure of the encryption. However, when the contour of the encrypted image is smeared due to smears of ink and optical deformation resulted from printing a digital image and reading the image using an optical apparatus such as a camera or a scanner, the original pixel values can not be recovered even when the reverse process is performed. Therefore, a problem has arisen that the image quality of the decrypted image is degraded.
As to the image in the encrypted area, this image is encrypted using a method of dividing the image into a plurality of blocks and rearranging (black/white inversion, mirror inversion, and upside-down inversion) the blocks. However, it can be considered that the image present before the encryption is speculated from the feature of the image of each block of the divided blocks when the blocks are only rearranged. Therefore, a problem has arisen that the security needs to be enhanced.


The present invention comprises a new and distinct variety of poinsettia, botanically known as Euphorbia pulcherrima and hereinafter referred to by the variety name ‘NPCW14233’. ‘NPCW14233’ is a selection from a branch mutation from the poinsettia variety ‘NPCW10158’ (U.S. Plant Pat. No. 22,580).
In November/December of 2008 a branch mutation was discovered on the poinsettia variety ‘NPCW10158’ in Nairobi, Kenya. Vegetative cuttings of the branch mutation were taken and propagated. In October of 2009, a single plant was selected in Stuttgart, Germany. In May of 2010, ‘NPCW14233’ was first asexually propagated by apical vegetative cuttings. ‘NPCW14233’ was found to reproduce true to type in successive generations of asexual propagation via apical vegetative cuttings in Stuttgart, Germany.


When designing a handset for use in mobile telephony, handset designers generally start with an ear model. Additionally, handset designers typically pay close attention to the requirements of the mobile telephone network operators (carriers) that will market and sell the handsets. Currently, carriers require that handsets be designed based on either a “high-leak” ear model or a “low-leak” ear model. In the high-leak ear model, an attempt at forming a seal between a mobile telephone handset and a user's ear is expected to form a consistent seal that has a significant acoustic leak. In the low-leak ear model, an attempt at forming a seal between a mobile telephone handset and a user's ear is expected to form a consistent seal that has insignificant acoustic leak.
A user of that handset may change the position of their ear relative to the handset, and subsequently the acoustic leak, throughout a phone call or based on personal holding position. Also, each user has a different acoustic load due to variations in ear size and shape; accordingly, the user may prefer a lower leak design or a higher leak design.
Tuning a handset often involves creating an optimum acoustic equalizer (EQ) setting. An acoustic EQ setting determines which frequencies of received audio are amplified, and to what extent, before the received audio is sent to a handset speaker, and, potentially, which frequencies are suppressed, and to what extent. The goal is to meet a specific “frequency-versus-level mask”. Such masks are determined by standards bodies, such as The 3rd Generation Partnership Project (3GPP, see www.3gpp.org).
However, during operation, users are often unable to form a consistent seal between the ear and the handset, due to movement and changes in position during the voice call. The amount of acoustic leak from the seal is dependent on the manner in which the handset is held by the user and the size and shape of the user's ear. Under those circumstances wherein the user forms a low-leak seal and the handset has been designed with a single acoustic EQ setting that assumes a high-leak seal, the user may complain about poor audio quality. For example, the user may complain that received audio sounds “boomy” or “muddy”. Given the variety of user ear shapes and sizes, along with the variety of manners in which users hold the handset, it may be quite difficult to establish a single acoustic EQ setting that will meet the requirements of all users and certification bodies.


1. Field of the Invention
The present invention relates generally to carbohydrate biochemistry. More specifically, the invention relates to starch biosynthesis and the enzyme(s) involved.
2. Description of the Related Art
Starch, the most significant carbohydrate reserve in plant storage tissues, comprises the glucose homopolymers amylose and amylopectin. Amylose consists of predominantly linear chains of xcex1-(1xe2x86x924)-linked glucose residues, whereas amylopectin is a highly branched glucan with a specific xe2x80x9cclusteredxe2x80x9d distribution of xcex1-(1xe2x86x926) glycosidic bonds (i.e. branch linkages) connecting linear chains (French, 1984; Manners, 1989).
Despite the relatively simple chemical structure of amylopectin, very little is known about the enzymatic processes responsible for formation of the highly specific and complex branching patterns in this polysaccharide. Biosynthesis of amylose and amylopectin involves activities of four groups of enzymes, each of which comprises multiple isozymes. These enzymes are ADPG pyrophosphorylases (AGPase), starch synthases (SS), starch branching enzymes (SBE) and starch debranching enzymes (SDBE) (Preiss, 1991; Hannah et al., 1993; Martin and Smith, 1995; Nelson and Pan, 1995; Ball et al., 1996; Preiss and Sivak, 1996; Smith et al., 1996). These enzymatic steps can account for all chemical linkages in starch, however, the specific roles of individual isozymes in formation of specific branching patterns in amylopectin and determination of starch granule structure and properties remain unknown.
Analysis of maize mutants with abnormal endosperm phenotypes has contributed greatly to the understanding of starch synthesis (Shannon and Garwood, 1984; Nelson and Pan, 1995) and facilitated the identification of many genes coding for starch biosynthetic enzymes. Cloned genes whose products are thought to be involved directly in starch biosynthesis are waxy (wx), coding for the granule-bound starch synthase GBSSI (Shure et al., 1983; Klosgen et al., 1986), amylose extender (ae), coding for SBEIIb (Fisher et al., 1993; Stinard et al., 1993), shrunken2 (sh2) and brittle2 (bt2), coding for the large and small subunits of AGPase, respectively (Bae et al., 1990; Bhave et al., 1990), and sugary1 (su1), coding for the SDBE SU1 (James et al., 1995). The transposon-tagging strategy was used to determine that the abnormal endosperm phenotype of wx-, ae-, or su1-mutants results from primary defects in GBSSI, SBEIIb, or SU1, respectively, and this approach remains the most effective way to identify genes such as dull1 (du1), in which the primary defect can not be associated with a particular enzyme deficiency.
The du1-mutations define a gene with a very important function in starch synthesis, as indicated by extensive structural analyses of starch from du1-mutant endosperms, and by the effects of these mutations when combined with other genetic deficiencies in starch biosynthetic enzymes (Shannon and Garwood, 1984; Nelson and Pan, 1995). The reference mutation du1-Ref was first identified as a recessive modifier of su1-Ref and su1-amylaceous (su1-am) (Mangelsdorf, 1947). Mutations of du1, when homozygous in otherwise non-mutant backgrounds, result in mature kernels with a tarnished, glassy, and somewhat dull appearance referred to as the xe2x80x9cdull phenotypexe2x80x9d. Expression of this phenotype, however, depends on the particular genetic background (Mangelsdorf, 1947; Davis et al., 1955). Total carbohydrate and starch content in mature du1- mutant kernels is slightly lower than normal (Creech, 1965; Creech and McArdle, 1966). The apparent amylose content in starch from du1-mutants is slightly or greatly elevated compared to normal depending on the genetic background (Shannon and Garwood, 1984), although the properties of polysaccharides in the apparent amylose fraction are essentially not altered (Dvonch et al., 1951). Approximately 15% of the starch in du1-mutant endosperms is in a form known as xe2x80x9cintermediate materialxe2x80x9d, which is distinguished from amylose and amylopectin by the properties of its starch-iodine complex (Wang et al., 1993b). Analysis of combined amylopectin/intermediate material fractions indicated that starch from du1-mutants has the highest degree of branching among a wide variety of normal and mutant kernels analyzed (Inouchi et al., 1987; Wang et al., 1993a; Wang et al., 1993b). Starch granules from du1-mutants seem to have normal structural and physical properties, although some abnormally shaped granules are found in the mutant endosperm (Shannon and Garwood, 1984).
Despite these subtle effects exerted by the single mutation, du1-alleles when combined with other mutations affecting starch synthesis result in a broad range of more severe alterations (Shannon and Garwood, 1984; Nelson and Pan, 1995). Mutations of du1 have been examined in combination with wx-, ae-, su1-, and sugary2 (su2-) mutations, and in all instances the double mutant kernels contained more soluble sugars and less total starch than when any of the mutations was present alone. In many instances the double mutants also produce polysaccharide forms that are distinct from the starch found in any single mutant kernels. These pleiotropic effects indicate the product of Du1 affects many aspects of starch biosynthesis in maize endosperm, however, without knowing the identity of this protein it is difficult to assess its specific functions.
Consistent with the pleiotropic genetic effects, du1-mutations cause reduced activity in endosperm of two seemingly unrelated starch biosynthetic enzymes, the starch synthase SSII and the branching enzyme SBEIIa (Boyer and Preiss, 1981). SSII is one of two enzymatically distinct starch synthase activities identified in the soluble fraction of maize endosperm; in vitro activity of SSII requires an exogenous glucan primer, and its molecular weight was determined in different studies as either 95 kD or 180 kD (Boyer and Preiss, 1981; Mu et al., 1994). Similarly, SBEIIa is one of the three known SBE isozymes in endosperm cells (Boyer and Preiss, 1978b; Fisher et al., 1993; Fisher et al., 1995; Gao et al., 1997). Several possibilities exist to explain the dual biochemical effects of du1-mutations. Du1 may code for a protein regulating the expression or activity of both SSII and SBEIIa. Alternatively, Du1 may code for either of these two enzymes, and the deficiency in one enzyme might also affect the second enzyme because of a direct or substrate-mediated physical interaction.
DU1 codes for a starch synthase, as indicated by the extensive-similarity of its deduced amino acid sequence to potato SSIII, and by the substantial similarity between the C-terminal residues of DU1 and a large group of phylogenetically diverse starch- and glycogen synthases. Particularly striking are two regions that together comprise more than half of the deduced DU1 sequence of 1,674 residues, which share very high similarity of 51% and 73%, respectively, with the corresponding regions of the potato SSIII sequence. Within a stretch of 450 amino acids at the C-terminus of DU1 nearly 30% of the best aligned residues are identical in comparisons to a wide variety of starch- and glycogen synthases, suggesting the location of a domain within DU1 that provides xcex1-1,4-glycosyltransferase activity.
The starch synthase coded for by Du1 is the soluble isozyme identified biochemically as SSII (Ozbun et al., 1971; Boyer and Preiss, 1981). The deduced molecular weight of DU1 including a potential transit peptide, 188 kD, matches closely with that of 180 kD reported for mature SSII lacking a transit peptide (Mu et al., 1994). The size difference of approximate 8 kD may be due to the transit peptide present in the deduced DU1 sequence. The tissue specific expression pattern of the Du1 mRNA also matches the expression pattern of SSII. Du1 transcripts were undetectable in leaves either by RNA gel blot or RT-PCR analyses, corresponding with that fact no detectable SSII activity was present in leaf extracts (Dang and Boyer, 1988). Moreover, the activity of SSII, along with that of SBEIIa, was greatly reduced in du1-mutant endosperm (Boyer and Preiss, 1981). Therefore, it appears that the maize du1 locus codes for the soluble starch synthase SSII, the counterpart of potato SSIII.
This characterization of DU1 implies that the phenotypic effects of du1-mutations, including changes in starch structure, deficiencies of two starch biosynthetic enzymes, and genetic interactions with ae-, su1-, su2-, and wx- mutations, all result either directly or indirectly from alteration of SSII. The reduction of SBEIIa activity in du1-mutant endosperm could result from the SSII deficiency owing to physical interaction between the two enzymes. A direct physical association of SSII and SBEIIa is implied by the observation that peak activities of both SSII and SBEIIa always coincide in the same DEAE-cellulose column fractions (Boyer and Preiss, 1978a; Boyer and Preiss, 1981; Dang and Boyer, 1988). Thus, SSII and SBEIIa may function together in vivo in the form of single multi-enzyme complex. Loss of the intact enzyme complex owing to reduction of SSII in du1-mutant endosperm may result in abnormally rapid proteolytic turnover of SBEIIa, or prevent accumulation of the enzyme by some other mechanism. Alternatively, expression of the Sbe2a gene in du1-mutant endosperm may be inhibited as a more indirect consequence of the deficiency in SSII, for example through reduction of a transcriptional inducer or elevation of a repressor. Although the du1-Ref mutation does indirectly affect expression of other starch biosynthetic genes (Giroux et al., 1994), it actually caused increased gene expression rather than the reduction observed for SBEIIa. Furthermore, considering that large glucose polymers are expected to be the substrate and product of DU1, down-regulation of Sbe2b expression by a transcriptional mechanism seems unlikely. Thus, the former hypothesis may explain the deficiency of SBEIIa in du1-mutant endosperm.
The broad impact of the combination of du1-mutations with various su1-alleles on kernel phenotype and starch synthesis (Cameron, 1947; Shannon and Garwood, 1984) could be explained by the SU1 SDBE also interacting closely with SSII in vivo, perhaps in the same enzyme complex with SBEIIa. This proposed association of SBEIIa and SU1 in a multi-enzyme complex is consistent with the proposed simultaneous branching and debranching actions during amylopectin synthesis by SBE and SDBE (James et al., 1995; Nelson and Pan, 1995; Ball et al., 1996).
Thus, the prior art is deficient in understanding the complex association of enzymes involved in starch synthesis and in cloning genes corresponding to these enzymes. The present invention fulfills this long-standing need and desire in the art.
To illustrate the role of the du1locus in starch biosynthesis, a transposon-tagging strategy was used to isolate the gene and describe its polypeptide product. The present invention reports tagging of the du1 locus with a Mutator (Mu) transposon, cloning and characterization of a portion of the gene, and the sequence of a near full-length cDNA (SEQ ID No. 1). The amino acid sequence deduced from this cDNA indicates Du1 codes for a 186 kD polypeptide extremely similar to SSIII, a starch synthase from potato tubers (Abel et al., 1996; Marshall et al., 1996). The expression pattern of Du1 also was characterized. Taken together these characterizations indicate that Du1 most likely codes for SSII of maize endosperm. In addition, the product of Du1 contains unique sequence features in its amino terminus that may mediate direct interactions with other starch biosynthetic enzymes.
One object of the present invention is to provide an enzyme with which to regulate the production of starch, and with which to produce altered or novel forms of starch.
In an embodiment of the present invention, there is provided a cDNA corresponding to the dull1 gene of maize.
In yet another embodiment of the present invention, there is provided an expression vector containing the sequence of dull1 with which to produce the starch synthase enzyme in transgenic plants or other prokaryotic or eukaryotic organism.
In yet another embodiment of the present invention, there is provided (1) cDNA having the nucleotide sequence comprising nt 120 to nt 1221 of SEQ ID No. 1, said sequence encoding the first 368 amino acids of DU1; (2) cDNA having the nucleotide sequence comprising nt 655 to nt 1221 of SEQ ID No. 1, said sequence encoding amino acids 180 to 368 of DU1; (3) cDNA having the nucleotide sequence comprising nt 565 to nt 816 of SEQ ID No. 1, said sequence encoding amino acids 150 to 233 of DU1; (4) cDNA having the nucleotide sequence comprising nt 1369 to nt 1944 of SEQ ID No. 1, said sequence encoding amino acids 418 to 609 of DU1; (5) cDNA having the nucleotide sequence comprising nt 1 to nt 1437 of SEQ ID No. 1, said sequence encoding amino acids 1 to 440 of DU1; (6) cDNA having the nucleotide sequence comprising nt 1438 to nt 2424 of SEQ ID No. 1, said sequence encoding amino acids 441 to 769 of DU1; (7) cDNA having the nucleotide sequence comprising nt 2425 to nt 3791 of SEQ ID No. 1, said sequence encoding amino acids 769 to 1225 of DU1
Other and further aspects, features, and advantages of the present invention will be apparent from the following description of the presently preferred embodiments of the invention. These embodiments are given for the purpose of disclosure.


Backlight is an important constituent part of a liquid crystal module. A main operation module of a backlight is a Light Emitting Diode (LED) driver and an LED light. Therefore, an operation voltage and operation current of the LED light are major factors which influence power consumption of the backlight.
A calculation formula of the power consumption of the backlight is: power consumption=voltage×current. The LED light is a physical element with PN junction characteristics, and as operation time elapses, current flowing through the LED light may increase with temperature increases at a constant voltage, and thus the power consumption also increases therewith.


The present invention relates to a phase change memory.
Phase change memories use a class of materials that have the property of switching between two phases having distinct electrical characteristics, associated to two different crystallographic structures of the material, and precisely an amorphous, disordered phase and a crystalline or polycrystalline, ordered phase. The two phases are hence associated to resistivities of considerably different values.
Currently, the alloys of elements of group VI of the periodic table, such as Te or Se, referred to as chalcogenides or chalcogenic materials, can be used advantageously in phase change memory cells. The currently most promising chalcogenide is formed from an alloy of Ge, Sb and Te (Ge2Sb2Te5).
In the chalcogenides, the resistivity may vary by two or more orders of magnitude when the material passes from the amorphous (more resistive) phase to the crystalline (more conductive) phase, and vice versa.
Phase change can be obtained by locally increasing the temperature. Below 150° C., both the phases are relatively stable, with an amorphous bit tending to gradually crystallize over a period of years if held at 150° C. Starting from an amorphous state, and raising the temperature above 200° C., where there is a rapid nucleation of the crystallites and, if the material is kept at the crystallization temperature for a sufficiently long time, it undergoes a phase change and becomes crystalline. Preferably, the material is cooled off slowly to better assure the crystalline state. To bring the chalcogenide back to the amorphous state it is necessary to raise the temperature above the melting temperature (approximately 600° C.) and then rapidly cool off the chalcogenide.


1. Field of the Invention
The present invention relates to a device which separates various objects from image data and which performs image processing on the objects thus extracted, and more specifically relates to a device which determines whether to perform the vector transform on an object in accordance with a characteristic of the object, i.e. an object attribute and/or the type of job set for the object.
2. Description of the Related Art
The spreading of digital cameras and image scanners today allows photo images to be digitalized easier than before. What has been made possible, for example, is: taking digitized photo images into a personal computer (hereafter, simply referred to as a PC); storing the images as image files; and processing and editing the image files by application programs. In addition, the image files of the photo images thus processed and edited can be laid out in an electronic document, such as a text document and a drawing. In this way, an electronic document that has photo images incorporated therein can be created.
In addition, a digital multifunctional peripheral that integrates functions of a scanner, a copier, a printer, a fax, and the like can be connected to a PC through a communication network, such as a LAN and the Internet. Such networking allows the PC to send, to the digital multifunctional peripheral, such electronic documents as a text document or a drawing incorporating a photo image taken by a digital camera. Then, the digital multifunctional peripheral can print out the received electronic document.
There exists a well-known image processing system capable of compressing image data to a higher degree while maintaining quality of an image, by separating the image data into a plurality of objects, and then by performing image processing and encoding processing on each of the objects. In addition, Japanese Patent Laid-Open No. H05-211607 discloses a method of reducing image degradation. The method includes: extracting a character object from image data; detecting a contour of the character object; and switching between smoothing the detected contour and not smoothing the detected contour. Here, whether to perform smoothing the detected contour is determined in accordance with a magnification specified by a user.
In the above-described conventional technique, after a character object is extracted from image data, transform processing from the image data into vector data (a vector image), such as a contour-extraction processing is always performed without consideration of a characteristic of the extracted character object. Note that, the contour-extraction processing, in general, takes a large amount of time. Accordingly, transforming image data into vector data without considering the characteristic of the object is likely to be a factor to lower the performance of the device.


1. Technical Field
The present disclosure relates to a lens barrel provided with an optical system.
2. Related Art
JP 2012-53411 A discloses a lens barrel which enables zooming.


Enteropeptidase is a serine protease that converts trypsinogen secreted from the pancreas after meal to trypsin. Trypsin in a state activated by enteropeptidase then activates protease precursors such as chymotrypsinogen, procarboxypeptidase, and proelastase. These activated proteases decompose dietary proteins into amino acid units. The resulting amino acids are absorbed into the small intestine. Thus, enteropeptidase inhibitors are capable of suppressing the degradation or absorption of proteins and is useful as a drug for treating obesity.
Examples of heterocyclic compounds include the following:
(1) A compound which has a trypsin inhibitory effect and is useful in the treatment or prevention of a renal disease or a disease involving trypsin, the compound being represented by the following formula:
wherein
ring A represents

R1 represents halogen, lower alkyl, or OH;
R2 represents H, optionally substituted cycloalkyl, optionally substituted aryl, an optionally substituted aromatic heterocyclic ring, an optionally substituted nonaromatic heterocyclic ring, —C(O)-lower alkylene-optionally substituted aryl, or lower alkyl optionally substituted by halogen or the like;
L1 represents —Y1-lower alkylene-Y2—, or —C(O)—N(R6)—;
Y1 represents a bond or —C(O)—;
Y2 represents a bond, —N(R6)—, or —C(O)—N(R6)—;
L2 represents -(lower alkylene optionally substituted by CO2H or the like)-, —Y3-cyclohexanediyl-Y4—, or —Y3-phenylene-Y4—, and L2 optionally forms optionally substituted cyclic amino together with R2;
Y3 represents a bond or lower alkylene;
Y4 represents a bond, lower alkylene, or —C(O)—;
R3 represents H, lower alkyl optionally substituted by halogen, halogen, OH, —O-lower alkyl, cycloalkyl, aryl, or the like;
R4 represents lower alkyl optionally substituted by halogen, halogen, OH, —O-lower alkyl, cycloalkyl, aryl, or the like;
R5 and R6 each represent H or lower alkyl;
X1, X2, and X3 each represent CH or N (except that at least one of X1, X2, and X3 is N);
m represents an integer of 0 to 4;
p represents an integer of 0 to 3; and
q represents an integer of 0 to 4
(Patent Literature 1).
(2) A compound which has a serine protease inhibitory effect and is useful in the treatment or prevention of obesity, hyperlipidemia, diabetes mellitus, diabetic complications, or metabolic syndrome, the compound being represented by the following formula:
wherein
R1, R2, R3, and R4 each represent H or the like;
HetAr represents an optionally substituted heteroaromatic ring;
X represents optionally substituted lower alkylene or the like;
Y represents carbonyl or the like;
A represents
or the like; and
R6 and R7 each represent H, optionally substituted lower alkyl, or the like
(Patent Literature 2).
(3) A compound which has a serine protease inhibitory effect and is useful in the treatment or prevention of obesity, hyperlipidemia, diabetes mellitus, diabetic complications, or metabolic syndrome, the compound being represented by the following formula:
wherein
D represents a benzene ring, a naphthalene ring, or a pyridine ring;
Het represents a heterocyclic ring;
R1 represents H or the like;
R2 represents nitro, lower alkyl, or the like;
X represents optionally substituted lower alkylene;
Z represents —N(R3)-(wherein R3 represents H, optionally substituted lower alkyl, optionally substituted lower cycloalkyl, or the like);
Y represents a single bond or —(CH2)p-C(R4a) (R4b)-(CH2)q- (wherein R4a and R4b each represent H, lower alkyl, or aralkyl, and p and q each represents an integer of 0 to 5); and
A represents —CO2R6 (wherein R6 represents H or lower alkyl) or
wherein Q represents optionally substituted lower alkylene, and R7 represents H or lower alkyl(Patent Literature 3).
(4) A compound which has an enteropeptidase inhibitory effect and is useful in the treatment or prevention of a disease related to obesity or abnormal fat metabolism, the compound being represented by the following formula:
wherein
B represents boron;
W represents a nitrogen-containing functional group (

X represents a linker (CX1X2)p;
Y and Z each represent OH, OR (R represents alkyl), a homocyclic ring, a heterocyclic ring, or the like;
R2 represents aminoacyl, acyl, or the like; and
R2 represents H, alkyl, or OR (R represents H or alkyl)
(Patent Literature 4).
(5) A compound which has a serine protease inhibitory effect and is useful in the treatment or prevention of obesity, diabetes mellitus, or the like, the compound being represented by the following formula:
wherein
R1 and R2 each represent alkyl or the like; and
X represents —OR3, —NR4R5, or the like
(Patent Literature 5).


It is already a known practice to place turbulators in the fluid circulation tubes of heat exchangers in order to increase heat exchanger efficiency by forming turbulence in the flow of fluid along the tubes.
Up to now, turbulators have often been in the form of highly elongate, very thin, rectangular strips of ductile material such as aluminum having baffles punched out from the strip and projecting from both faces thereof. However, it to be observed that such turbulators are deformable and difficult to insert into the tubes, in particular when the tubes are of oblong or oval cross section. This is because the turbulator strips are so thin and because of the baffles projecting from both sides thereof.
Preferred embodiments of the present invention mitigate these drawbacks.


Cut flowers have become increasingly popular and are sold at florists, in grocery stores or the like, and often by street vendors. One of the disadvantages of buying cut flowers at the less expensive outlets, i.e., street vendors and/or supermarkets, is that they are often delivered to you, and you hence deliver them, in unattractive plastic bags.
A viable alternative to the plastic bag is a, heretofore unavailable, attractive vase structure which is inexpensive and may be stored in a flat condition, but quickly and easily assembled into a water-and-stem-holding container.
Prior art known to the inventor, in addition to the plastic bag method described hereinabove, includes U.S. Pat. No. 404,585 granted to Wright, June 4, 1889, which discloses a pot made of paper having its bottom folded inwardly such that once the pot, containing dirt and rootball are positioned in the appropriate place beneath the soil, the pot is pulled upwardly providing a protective shield for the seedling.
U.S. Pat. No. 2,150,453 granted to Mulford, et al., Mar. 14, 1939, discloses several packages which may be constructed from precut and prefolded blanks to form a flower pot. A bulb, purchased in the pot, may be grown in the pot by the purchaser such that the bulb may never need to be transplanted.
U.S. Pat. No. 2,340,373 granted to Gardner, Feb. 1, 1944, discloses a plant pack that includes a single-piece exterior shipping container and interior means to secure the plant within the container preventing movement during shipping.
U.S. Pat. No. 3,373,917 granted Mar. 19, 1968 to Cox, discloses a cup including a foldable exterior casing and a fluid-impervious liner.
U.S. Pat. No. 4,209,092 granted June 24, 1980 to Jones, discloses a plant container fabricated of a single sheet of material having predetermined fold lines and including a sealing strip for securing the container in its usable three-dimensional configuration.
U.S. Pat. No. 4,347,686 granted Sept. 7, 1982 to Wood, discloses a container for plant life which is folded such that it forms a cone or pyramid for facilitating aerial planting. The device may include a solid nose piece and fins for guidance.


Current high-volume, high-availability, content distribution networks use clusters of Web servers to achieve scalability and reliability. To serve a large and diverse client population, content can be replicated across servers, or partitioned with a dedicated server for particular content or clients. In such environments a front-end dispatcher (usually called a “web switch” or a “reverse proxy” based on its functional usage) directs incoming client requests to one of the server machines. The request-routing decision can be based on a number of criteria, including requested content, server load, client request, or client identity.
Dispatchers are typically required to perform several functions related to the routing decision. These include:                distribute incoming requests as to balance the load across servers;        examine client requests to determine which server is appropriate to handle the request (i.e., content-based routing);        identify the client to maintain affinity with a particular server for e-business applications or to provide service differentiation.
Dispatchers may be broadly categorized into two types: layer-4 dispatchers which base decisions on TCP and IP headers alone, and layer-7 dispatchers which use application layer information (e.g., HTTP headers) to direct clients. The use of layer-4 or layer-7 dispatchers depends on the request-routing goal. Load-balancing across replicated content servers, for example, typically does not require knowledge of the client request or identity, and thus is well-suited to a layer-4 approach. Content-based routing requires the dispatcher to terminate the incoming connection, examine the higher-layer headers, and either create a new connection with the appropriate server (using connection splicing), or transfer the connection to the appropriate server (using connection handoff). Layer-7 dispatchers, while more sophisticated, suffer from limitations on scalability and performance since they must perform connection termination and management for a large number of clients.
High-speed switching hardware is also commonplace in core ISP networks with a growing migration to Multiprotocol Label Switching (MPLS). MPLS provides a circuit-switching service in a hop-by-hop routed network and is presently used for flexible routing, traffic engineering and Virtual Private Networks (VPNs). It achieves this by grouping related packets by assigning them a common, fixed-size label. Packets sharing a label belong to the same forwarding equivalence class (FEC) and can be routed and treated the same way in the network. Standard usage of MPLS involves establishment of arbitrary label-switched paths (LSPs) for forwarding particular classes of traffic. LSPs may also be nested by stacking MPLS labels where an outer label might be used to assign traffic to a common network-wide path, while an inner label could be used to demultiplex traffic among classes of traffic on that path. An MPLS-enabled network includes of label-switched routers(LSRs) that implement the MPLS protocols.
MPLS labels do not have built-in semantics, i.e. labels are used only to map a packet from an LSR input port to an LSR output port. It would be advantageous to make use of this flexibility by mapping application-layer information onto labels to enable high-performance Web switching, rather than using labels to express routing and forwarding policies (as is customary).


1. Field of the Invention
The present invention relates to metal oxide based memory devices and methods for manufacturing such devices.
2. Description of Related Art
Resistive random access memory, RRAM, is a type of nonvolatile memory that provides the benefits of small cell size, scalability, ultrafast operation, low-power operation, high endurance, good retention, large On/Off ratio, and CMOS compatibility. One type of RRAM includes metal oxide layers than can be caused to change resistance between two or more stable resistance ranges by application of electrical pulses at levels suitable for implementation in integrated circuits.
In prior methods of forming a transition metal oxide (TMO) memory layer, photoresist is used as an etching mask to protect the portions of TMO in a designated region that will be the memory layer, while other portions of TMO that are not part of the memory layer are etched away. After etching, the photoresist is stripped and this stripping may cause damage to the TMO memory layer. Prior methods of avoiding this damage caused by stripping have included using a hard mask such as SiO2 or Si3N4 prior to oxidization to define surfaces to be oxidized to form the TMO memory layers. By defining which regions to oxidize, the step of etching away unwanted oxidized regions is eliminated. However, this process of using a hard mask adds two extra processes to the previously described method involving damage caused by the photoresist strip. These additional steps in the process add time and cost to production, which are undesirable.
It is therefore desirable to provide a memory cell and method of manufacture that eliminates the possibility of damage to the TMO memory layer caused by a photoresist strip while adding a minimal amount of manufacturing steps in order to provide a cost-effective method of manufacture.


1. Field of the Invention
The present invention relates to a method of forming an oxide film and further a method of manufacturing an electronic device utilizing an oxide film.
2. Description of the Prior Art
In recent years, researchers are attracted by thin film transistors utilizing non-single crystalline semiconductor thin films.
Conventionally, such a non-single crystalline semiconductor thin film is formed on an insulating substrate by chemical vapor deposition, so that a temperature during the film formation is as low as 450° C. or less. Therefore, soda-lime glass, boro-silicate glass, and the like can be used as the substrate.
The thin film transistor recently attracting researchers is a field effect transistor (simply referred to as FET) having the same function as that of MOS FET. The size of the thin film transistor is limited only by the size of the apparatus to be used for formation of a semiconductor thin film constituting the transistor, so that it is easy to form transistors on large-sized substrates. Such large-sized thin film transistors are promising. For example, the large-sized thin film transistors can be used as switching elements of liquid crystal displays having a lot of pixels in the form of matrix or switching elements of one dimensional or two dimensional image sensors or the like.
It is possible to implement a conventional fine processing to the semiconductor thin films. Hence, the thin film transistor can be formed by means of a conventional fine processing, for example photolithography technique. And it is also possible to make the thin film transistor integrated as a function element of a part of monolithic IC.
Referring to FIG. 2, a typical structure of a conventional thin film transistor is schematically illustrated.
Source and drain electrodes 24 and 25 are provided on an insulating substrate 20 made of glass and source and drain regions 22 and 23 are provided on the source and drain electrodes 24 and 25 respectively and a non-single crystalline semiconductor thin film 21 is provided on the substrate 20 and a gate insulating film 26 is provided on the semiconductor thin film 21 and a gate electrode 27 is provided on the gate insulating film 26.
In the thin film transistor, electric current flowing between the source region 22 and the drain region 23 is controlled by a voltage applied to the gate electrode 27.
A gate oxide film constituting such a thin film transistor was conventionally formed by exposing a semiconductor material to thermal oxidation or by thermal CVD under a reduced or atmospheric pressure, or the like.
Electric characteristics of the thin film transistor largely depend on the quality of a channel region of the semiconductor film and the quality of the gate insulating film. For this reason, a gate insulating film of particularly good quality has eagerly been required.
In the case of the formation of the gate oxide film by exposing a semiconductor material to thermal oxidation or by thermal CVD under a reduced or atmospheric pressure, the temperature during the formation of the gate insulating film should be as high as approximately 600° C. in order to obtain a thin film transistor of good electric characteristics. So that, a heat-resistant substrate material such as quartz glass had to be utilized though it is expensive.
With respect to a method for forming a gate insulating film at a low temperature, a plasma CVD and a sputtering method utilizing an argon gas for sputtering are well-known. This sputtering method is implemented in an atmosphere comprising a large amount of argon, specifically an atmosphere comprising 100 to 80 volume % Ar atoms and 0 to 10 volume % oxygen. This is because probability of an atom or a cluster of atoms being dislodged from a target by collision of one inert gas atom, for example one Ar atom, is high (in other words, sputtering yield of Ar gas is high). However, in both the plasma CVD and the sputtering method using a large amount of argon, the gate insulating film involves numbers of elements (e.g. inert gas elements such as Ar) which was involved in a target or existed in a chamber during the CVD or the sputtering, resulting in generation of fixed electric charges in the gate insulating film. Further, ions of the elements bombard a surface of an activated layer in a thin film transistor and thereby give a damage thereto. Hereupon, a mixed layer of the activated layer and the gate insulating film is formed in the vicinity of an interface between the activated layer and the gate insulating film. As a result, interfacial level is formed at the interface and a thin film transistor of fine characteristics cannot be obtained by any of those methods.
It has been attempted to form a gate insulating film by a photo CVD method, and an interfacial level density of the gate insulating film was about 2×1010 eV−1 cm−2, almost the same as that of a thermal oxidation film. However, the photo CVD method required a long period of time, in other words, the film formation speed was extremely slow, so that the photo CVD method was not suitable for an industrial application.
Referring now to FIG. 7, a network of silicon oxide formed by sputtering in an atmosphere comprising a large amount of argon is illustrated. Symbols 0 in the drawing indicate oxygen or silicon and symbols X indicate dangling bonds of silicon. A silicon oxide film including a gate insulating film is not dense when quantity of fixed electric charges is large in the silicon oxide film. The larger the number of dangling bonds of silicon in the silicon oxide film is, the larger the quantity of fixed electric charges is. And the larger the number of Ar+ in the silicon oxide film is, the larger the quantity of fixed electric charges is. Ar+ and Ar tend to stay inside the silicon oxide network as illustrated in FIG. 7 (Ar+ and Ar do not tend to be substituted for Si or 0 in the network). In fact, numbers of dangling bonds of silicon tend to be generated in the silicon oxide film when the silicon oxide film is formed by sputtering in an atmosphere comprising a large amount of argon. This is partly because internal stress is generated in the silicon oxide film by Ar or Ar+ present inside the silicon oxide network and partly because defects are formed in the silicon oxide film by bombardment of argon with the silicon oxide film during sputtering.


In base stations for personal communications systems, for example used for the Global System for Mobile communications (GSM), Enhanced Data Rates for GSM Evolution (EDGE), Wideband Code Division Multiple Access (W-CDMA), radio frequency (RF) power amplifiers are among the key components. For these power amplifiers, RF power laterally diffused metal oxide semiconductor (LDMOS) transistors are a commonly used technology. They exhibit excellent high power capabilities, gain and linearity. These metal oxide semiconductor (MOS) transistors are not only used in base stations but also in radar and broadcast applications. If a RF mismatch occurs at the output of the LDMOS, power will be reflected back at the LDMOS and the LDMOS must be able to handle this. Thus ruggedness, i.e. the capacity to sink excess energy without damage, is an important issue for RF power LDMOS transistors. For low-frequency applications, ruggedness can be improved by adding external diodes with appropriate breakdown voltages. The diodes will sink electrical energy and thus prevent damage to the LDMOS. For RF LDMOS transistors with high frequency applications, external diodes would degrade the RF performance and the ruggedness improvement would be insufficient. It is also conceivable to sink electrical energy through the drain to substrate diode, if the drain-substrate diode is able to sink enough energy before the voltage reaches a level at which the parasitic bipolar transistor is turned on and the LDMOS is damaged. However, the breakdown often starts locally in a specific section of the drain, which determines a low breakdown voltage but doesn't give a high breakdown current.
It is therefore an object of the invention to improve a laterally diffused metal oxide semiconductor circuit for a radio frequency power amplifier in a way that allows the adjusting of a breakdown voltage at which breakdown will occur with a higher breakdown current.


The present invention relates to coating processes and compositions, and more particularly to processes and coating compositions for suppressing combustion of metals, and to the products of such processes.
The relatively high strength, low density and high melting point of titanium has led to increasing use of titanium and titanium alloys in aircraft engine components such as fan and compressor vanes and blades, and in other applications. However, titanium can be made to ignite and react with air in an exothermic self-sustaining rapid oxidation process referred to as combustion. Titanium has a high heat of combustion, low thermal conductivity and a spontaneous ignition temperature below its melting point. These properties favor ignition and subsequent propagation of titanium or titanium alloy combustion rather than melting, thus producing additional rapid local temperature increases and rapid propagation of the resultant combustion once ignition occurs. During operation of aircraft jet engines, titanium blade ignition is often caused by rub. An abradable seal of rubber, felt metal or nickel-graphite, is present on the engine shroud adjacent to the compressor blades to prevent gas backflow and consequent loss of pressure. Without such a seal, efficiency of the compressor would be severely impaired. Accordingly, seal-blade separation is necessarily small. During engine operation, the blades heat up, expand with heat, and even creep, so that some blades thereby rub against the seal. Severe rubbing and abrasion may occur when an engine part fails, putting the engine out of balance, or when a failed blade imbeds itself in the seal. This abrasion between seal and blade(s) can cause ignition of the titanium. The high-velocity air stream in jet engines aids further to the combustion of any titanium or titanium alloy component that ignites and causes burning particles and molten metal to be sloughed off therefrom. These particles can be entrained in the engine air stream and impinge on downstream engine components to ignite them and thereby spread combustion in the engine. Some single-layer metallic and organic coatings have been used for reducing combustion of titanium substrates. However, an organic coating, particularly its binder, will generally vaporize or burn off, before its protection is needed, in a 600.degree. F.-900.degree. F. working environment such as found in operating jet turbine aircraft engines. Also, many metals, particularly those capable of forming an intermetallic with the substrate metal, can if coated on the substrate diffuse into and significantly degrade engineering or mechanical properties, such as fatigue endurance, of the substrate, particularly in a relatively hot gas turbine engine environment.


Electronic navigation systems provide for the identification and tracking of the physical location of a user and are, in many cases, also capable of directing users to a destination of their choice. These systems enable the presentation of a variety of way finding information such as the current physical location of the system user, intermediate waypoints and destination. Navigation systems can use both audio and/or visual methods to guide users to a destination. In addition to stored data relating to the physical environment, these systems may also allow users to locate businesses and points of interest by category, keywords, or through other querying capabilities. The inclusion of a particular business or point of interest in an electronic navigation system may or may not require a business or individual to pay a fee to provide for this inclusion. In addition to passive listings, navigation systems also have the ability to present advertisements to users, potentially allowing them to initiate a trip based on the advertisement.
In general, and unlike traditional media, electronic advertising via the internet, mobile phones or other electronic media have the benefit of being able to record data relating to the audiences' interaction with the advertisement. For example, internet based advertisements in the form of banner advertisements provide for the tracking of whether the advertisement was presented to the user as well as whether the user clicked on that advertisement to view more information about the subject of the advertisement. Advertising pricing models are often based on performance metrics relating to the number of views per advertisement.


Merchants find it useful to keep track of who their customers are, and how frequently their customers make purchases. Merchants regularly use this information to, for example, administer customer incentives programs, for marketing purposes, and to formulate advertising strategies.
For those customers that make purchases using a financial transaction card (e.g., a credit card, debit card, smart card, etc.), merchants potentially have available to them an easy way of obtaining both identifying and purchase frequency information. Every financial transaction card has stored on it data, such as the customer's personal account number (PAN), which is unique to a particular customer. Such financial transaction card data is extracted from the card and sent to the merchant during the course of a typical card-based transaction. Merchants could store that unique financial transaction card data, and use it to determine each time a purchase was made by a customer using a particular financial transaction card.
However, merchants are currently unable to make use of financial transaction card data to keep track of customers and purchase frequency. For security reasons, current payment schemes for financial transaction cards have dictated rules that forbid merchants from storing financial transaction card data that contains information about a customer's account. There remains a need in the art for a simple method and system that would allow merchants to uniquely identify their customers using financial transaction card data, but that does not require that the merchants store that data.


1. Field of the Invention
The present invention relates in general to loadcarrying vehicles, and, more particularly, to a novel transformer caddie for transporting and locating transformers and other equipment.
2. Description of the Prior Art
Modern underground residential distribution systems of electric power frequently include small pad-mounted distribution transformers located in unpaved areas behind homes, usually backyards, these areas being generally inaccessible to trucks and cranes typically employed in transporting and locating transformers and other relatively heavy electrical equipment. Periodic replacement of such transformers has, in the past, presented serious problems, particularly when replacement transformers must be moved through gates or other narrow passageways and into hilly terrain. Furthermore, the problems associated with transformer replacement are aggravated by mud and snow conditions.
One device used for transporting such distribution transformers is a small dolly or wheeled platform. However, since such transformers are frequently quite heavy, often weighing on the order of one ton or more, a rather large work crew has been found to be necessary to wheel and set a transformer into place on its pad using this device.
Another known device is a pole-carrying vehicle comprising an inverted U-shaped frame having a winch mounted on its top for suspending a load, the device having a pair of steerable front wheels similar to those found on a wagon. However, this device lacks maneuverability, particularly necessary for positioning a transformer onto its mounting pad. Furthermore, since this device is rather large, its lack of maneuverability prevents easy movement through narrow passageways.


(1) Technical Field
The invention relates to electronic circuits, and more particularly to bias circuits for cascode amplifiers, particularly radio frequency cascode amplifiers.
(2) Background
Amplifiers are a common component in radio frequency (RF) transmitters and receivers, and are frequently used for power amplification of transmitted RF signals and for low-noise amplification of received RF signals. For many RF systems, particularly those requiring portability (e.g., cellular telephones, WiFi-connected computers, cameras, and other devices, etc.), it has become common to use complementary metal-oxide semiconductor (CMOS) fabrication technology to create low cost, low power, complex integrated circuits (ICs). CMOS device technology improvements, such as silicon-on-sapphire (SOS) CMOS, silicon-on-insulator (SOI) CMOS, and ever-shrinking field-effect transistor (FET) device channel lengths, are putting the RF performance metrics of silicon-based CMOS transistors on par with rival gallium arsenide (GaAs) technologies.
FIG. 1 is a simplified schematic diagram of a prior art amplifier circuit 100. The illustrated circuit 100 has a cascode common source architecture constructed from two series-connected FETs. An RF input signal, RFIN, is applied through a biasing and coupling circuit 102 to the gate of a FET M1, the drain of which is coupled to (and thus drives) the source of a second FET M2. The source of M1 is coupled thorough a degeneration inductor L to RF ground. The degeneration inductor L, which will also have an inherent resistance R (shown in dotted outline), performs several functions, including obtaining a good dynamic range (e.g., a good noise figure), achieving high sensitivity with low power consumption, helping make input impedance matching easier, and improving linearity.
The second FET M2 has its gate coupled to a voltage source Vgate (which may be VDD in many cases) and provides an amplified RF output signal, RFOUT, at its drain. In some applications, the RF input signal, RFIN, may be processed through an input impedance matching network 104 before being coupled to the gate of M1, and in some applications, the RF output signal, RFOUT, may be processed through an output impedance matching network 106. While the illustrated cascode circuit provides good isolation because there is no direct coupling from the output to the input, the circuit is not well suited to applications in which the DC supply voltage varies, such as applications where the DC supply voltage at the drain is actively modified to optimize operation at different power levels; examples are average power tracking (APT), envelope tracking (ET), and GSM power amplifier power control. In these examples, the supply voltage VDD may have a range that varies by a factor of 10 or more (e.g., from 4.5V to 0.4V, as one example).
One problem area for using silicon-based CMOS transistors in cascode amplifier circuits is creating bias circuits, particularly in cases in which the DC supply voltage varies and in the case of amplifiers with a transistor stack height of 3 or more. In general, a DC bias voltage applied to the gate of a FET sets the gate-source voltage VGS so as to provide a desired drain current. Silicon-based CMOS devices with short channel lengths provide fast RF response—a desirable characteristic in an amplifier—but suffer from poor output resistance characteristics due to the influence of the drain voltage on the gate of a transistor device. As such, they are not amenable to common open-loop bias techniques, such as current mirrors, without suffering from a large and undesirable mismatch between a reference device current and the output device current. In addition, the problem can be further exasperated in SOS and SOI CMOS technologies due to issues associated with the floating body or “kink” effect. In the floating body effect, the body of a transistor may form a capacitor with the insulated substrate; charge accumulation on this capacitor may cause the formation of parasitic transistors consuming unwanted parasitic currents and further degrading the output resistance of devices intended to be used as current sources.
Another challenge in designing bias circuits for silicon-based CMOS cascode amplifiers is to configure such circuits so that they are tolerant of supply and bias voltage variations, and bias current variations. Traditional cascode bias circuits include diode connected devices which do not accommodate a wide range of supply and bias voltages. Bias current variations may be driven by variations in process, temperature, and voltage (i.e., “PVT” effects), the end result of which is to cause fluctuations in bias current leading to fluctuations in RF performance. Another drawback to using silicon-based CMOS devices for amplifier applications, and particularly for power amplifier applications, is a relatively low breakdown voltage per device.
Yet another challenge in designing RF amplifiers is that, in many applications, the RF electrical environment of a transmitter, receiver, or transceiver is constantly changing. The changing characteristics of an RF signal path affects RF circuit performance metrics such as gain, linearity, noise figure, and power consumption. A system performance profile that ideally sets such metrics for one situation (such as high gain, moderate linearity, and low noise in the presence of a small received signal) can be completely inappropriate as the RF environment changes (such as with increasing received signal power). These situation transitions can occur many times during a single usage session of an RF circuit (for example, as a cellular phone moves relative to signal towers), and not adjusting to an appropriate performance profile as the RF environment changes can result in poor or non-functioning RF circuit performance.
Accordingly, there is a need for bias circuits for silicon-based CMOS amplifier architectures that are tolerant of supply and bias voltage variations, bias current variations, and transistor stack height, and compensate for the poor output resistance characteristics of silicon-based CMOS devices with short channel lengths. There is also a need for amplifier architectures that can rapidly adapt to a changing RF electrical environment. Further, there is a need for improved silicon-based CMOS amplifier architectures having good isolation.


The orthogonal frequency-division multiplexing method (OFDM) has established itself in many areas for high-rate data transmission in radio systems with large bandwidth. It is used, for example, in digital audio broadcasting (DAB), digital video broadcasting-terrestrial (DVB-T), in wireless local area networks (WLAN) and 4G long term evolution LTE. The principle of OFDM consists of splitting the high-rate overall data stream into many low-rate data streams and transmitting them parallel via the corresponding number of orthogonal subcarriers. Compared to single-carrier methods, various advantages result for transmission via frequency selective multipath channels. In doing so, channel equalization can be implemented efficiently in the frequency range without using costly adaptive equalization filters. Furthermore, by introducing a guard interval (GI) between the OFDM symbols, inter-symbol interference (ISI) can be effectively prevented. Signal generation can be realized with the help of inverse discrete Fourier transform (IDFT) or its expense-favorable implementation, the inverse fast Fourier transform (IFFT).
An almost identical method is also used for line-tied transmission. It is known as “discrete multitone transmission” (DMT). It is used, for example, for broadband digital data transmission via subscriber connection lines (DSL). Because DMT can also be viewed as a form of OFDM, the term “OFDM” will be used for both module types, hereafter. Thus, the following remarks similarly refer to DMT systems.
One problem with the transmission via channels with distinct multi-path dispersion (e.g. by means of signals reflected at buildings during radio transmission or reflection onto lines during line-tied transmission) is that destructive interference can cause erasing of subcarriers (“spectral zeros”) in the channel). Because the symbols modulated onto the affected subcarriers cannot be detected correctly by the receiver, any longer, this causes a high symbol error rate (SER) or a high bit error rate (BER) in the data stream, which only slightly decreases with increasing signal to noise ratio (SNR). Thus, it cannot readily be compensated for by increasing the transmission capacity.
As a matter of principle, the problem can be avoided if the transmitter only modulates the data to the strong subcarriers and omits the weak or deleted subcarriers. This involves, however, that it knows the actual radio channel to the receiver (channel state information at transmitter's), which is not the case in many systems. The reasons for this are, for example, the higher complexity of the system connected therewith, and feedback information that may be used (transmission of channel information from receiver to transmitter), which cause a transmission overhead and have to be made available to transmitter with very little delay for a fast time-variable channel.
Generally, OFDM is coupled with forward error correction (FEC), which results in coded OFDM (COFDM). To do this, targeted redundancy is added to the sent data stream by means of suitable channel coding and used at receiver's to correct transmission errors. By means of FEC, BER can be significantly reduced, whereby the net data rate is decreased by the added redundancy—a defaulted net data rate involves correspondingly increased transmission resources. A linked FEC is oftentimes implemented in classic COFDM systems, where a convolution code is linked as inner code and a block code (e.g. Reed Solomon Code) is linked as outer code, for example. The inner code has the primary task to reduce the effects of the weak subcarriers or the spectral zeros. With the help of the outer code, the error rate is further reduced by several decimal powers.
One alternative to compensate for the influence of weak subcarriers is to spread data symbols prior to OFDM modulation in the frequency range. Every symbol is then no longer transmitted via a single but via all subcarriers, via which the spreading operation is being implemented. Any sub-carrier carries a linear combination of all transmission symbols within the block. Even in case of loss of several subcarriers, it is often times still possible to reconstruct the transmission symbols, and the BER strongly decreases around the operating point (as in the non-frequency selective case) with increasing SNR. This is referred to as diversity gain. The method is referred to as “code-spread OFDM” (CS-OFDM; see reference [1] —the stated references can be found in detail in Appendix 1 to this description), “spread OFDM” (SOFDM; see reference [2]) or “frequency domain spreading” (see reference [3]). The abbreviation CS-OFDM will be used, hereafter. Classically, M modulation symbols are spread onto/over N subcarriers, causing no loss in data rate. If M<N modulation symbols are spread onto N subcarriers, the system is referred to as “partially loaded” (PL) (PL CS-OFDM; see reference [1]). By means of partial load, further gains can be achieved at the expense of the data rate.
Compared to COFDM systems, no redundancy has to be added to CS-OFDM systems to utilize frequency diversity. An additional FEC with the help of channel coding is, however, generally reasonable to further reduce the error rate. Because the channel code used in such case, does not have to compensate for the influence of the weak subcarriers any longer, the code rate can turn out larger for classic coding methods in connection with the spreading.
CS-OFDM signals have unfavorable signal statistics, in common with OFDM signals. Interference of a plurality of subcarriers results in a poor ratio of instant performance to mean signal performance (signal statistics). This is often times indicated by the peak-to-average power ratio (PAPR), the ratio of maximum instant performance to mean signal performance or the crest factor (ratio of the maximum instant value to the root mean square value of the signal). The measurements take on high values for OFDM signals. Signal statistics deteriorates with increasing subcarrier number N.
High requirements to the linearity of the components used in the system, and especially to the power amplifiers, result from poor signal statistics. Therefore, such components can often times only be operated in an inefficient operating point. One problem for the PL CS-OFDM is the fact that the PAPR—in comparison to the fully loaded system—can drastically continue to deteriorate.
The presentation of the problem in respect to a CS-OFDM system is the realization of an efficient, adaptive transmission by means of an implementation with low complexity:                high performance ability: good utilization of the frequency diversity of the frequency selective channel, low bit error rate with given SNR and given net data rate        good signal statistics (low PAPR): low requirements to the linearity of the analog hardware (above all at the power amplifiers) and performance specific operating point        high adaptivity: adaptivity possibility of the transmission (robustness, net data rate, redundancy) to the conditions of the transmission channel with low complexity and fine tuning        implementation with low complexity: low utilization of resources of digital signal processing and low requirements to the speed of digital signal processing, cost and performance efficient implementation
Generally, the criteria cannot be optimized independently from another. Conventional technology knows several spreading methods with good properties, which will be described, hereafter.
Conventional technology describes Hadamard (also termed “Walsh-Hadamard” or “Hadamard-Walsh”; see references [1]-[4] and [5]), DFT (see references [3], [5]) as well as Vandermonde spreading (see reference [4]). These spreading methods are characterized by high performance ability. This applies at least to large spreading lengths, that is, if the spreading is being implemented by means of a high number of subcarriers. Modifications of the Hadamard transform and the discrete Fourier transform (DFT), the “rotated” Hadamard transform and the “rotated” DFT are suggested in reference [5] to improve performance ability for low spreading lengths.
An increase of CS-OFDM is introduced in references [1], [4]. It consists of feeding a low number of modulation symbols into the spreading operation, which are available as subcarriers, that is, in spreading M symbols onto N subcarriers, where M<N. The system is then referred to as “partially loaded” (PL CS-OFDM). The classic case, a fully loaded system, exists for M=N. Reference [1] suggests the use of PL CS-OFDM to realize further gains compared to OFDM and CS-OFDM, at the expense of the data rate.
For DFT spreading, recourse can be made to the fast Fourier transform (FFT), that is, an efficient algorithm for calculation of the discrete Fourier transform (DFT). The complexity amounts to O (N log2 (N)), with multiplications with the root of unity and additions that may be used. The Vandermonde spreading, a multiplication of a Vandermonde matrix of the dimension N×N with a symbol vector of the length N, can be realized with the complexity O (N log2 (N)) (multiplications and additions; see reference [17]). Hadamard spreading can be implemented with the help of the fast Walsh-Hadamard transform (FWHT). It involves N log (N) additions or subtractions and thus has the lowest computational complexity among the methods with full flexibility (fine-tuned partial load, selection of the carriers).
An implementation of the DFT spreading with particularly low complexity is described in reference [16]. In doing so, the multiple carrier system is reduced back to a single carrier system, so that the transmitter can be realized very easily, which, however, is not similarly applicable to the receiver in case a channel estimation and a channel equalization have to be implemented. Furthermore, the system is no longer fully flexible with respect to the partial load with full diversity and selection of the allocated subcarriers.
FIG. 1 shows a block diagram by means of which signal processing is explained in a conventional CS-OFDM transmitter. By means of an introduction, it should be noted that the mathematical notation used in this description is explained in Appendix 2 to this description. The matrices and sequences, to which reference is being made, are explained, there, as well. For better understanding, cross references to the sections of Appendix 2 are indicated at several locations. The abbreviations used are listed in Appendix 3 to this description.
FIG. 1 shows a processing chain 100 for generation of the spread OFDM signal. Mathematically, this can be illustrated with the help of vectors, matrices and corresponding operations. The stream of the (already coded, where applicable) data symbols ds is transformed with the help of a serial/parallel converter 102 in data vectors d of the length M. Spreading is being implemented at block 104. The type of spreading is entirely described by the spreading matrix D. Subsequently, the spread data vectors x are fed to IDFT 106. Blocks 104 and 106 can be combined in one block 108, which implements both the spreading and the IDFT. The combination of both operations is hereafter referred to as “overall transform”, and block 108, which implements such transform, as “overall transformer”. The transforming output vectors w can then be submitted to further operations in the digital baseband (e.g. inserting a Guard interval, fenestration). By means of a digital/analog converter, they are converted to analog signals and run through the typical processing chain of a transmitter for digital data processing, until emission via the antenna(s).
Mathematically, the spread data vector x results from a vector matrix multiplication of the spreading matrix D (dimension N×M) with the input vector d (length M, column vector):x=Dd.
IDFT 106 can be illustrated as multiplication with the IDFT matrix F−1 (see section 2.10 of Appendix 2) of the dimension N×N. We have:w=F−1x and consequentlyw=F−1Dd=:Bd, with the multiplication of vector d with the matrix B=F−1D illustrating the overall transform 108.
The spreading methods known in the art (see, for example, references [1]-[5]) can be characterized by means of matrices, in particular Hadamard, Vandermonde, and DFT matrices, (see definitions in sections 2.8, 2.9 and 2.10 of Appendix 2). With a full load of the system (M=N), D is identical to the characterizing matrix. With a partial load (M<N), a partial block or sub-block of the characterizing N×N matrix is used for D, which block consists of the first M matrix columns (see references [1], [4]). Spreading methods, which are based on a spreading matrix, are referred to as matrix-based spreading methods, hereafter.


Often times a homeowner is in his/her vehicle driving and they cannot recall whether they shut the garage door. If the garage door is not shut while the owner is not home, the house may be easily broken into by a criminal.
Additionally, a homeowner may be in his/her home and ready to go to bed. However, the homeowner cannot remember if he/she shut the garage door. Again if the garage door is not shut, the homeowner's family may be subjected to intruders.


Earrings are not easily stored in any organized fashion because of their small size and odd shapes, and the fact that they are used in pairs. The usual storage is accomplished by simply keeping them loose in a box or drawer, with the result that it is difficult to find a matching pair.
Display racks found in retails stores usually involve displaying small cards or boxes in which are fastened a single pair of earrings in a manner such that the earrings are not readily detachable. As such, these racks are totally unsuitable for use in the home where one wants to quickly find and remove from storage a selected pair of earrings. Insofar as is known, there is no such storage rack available at the present time, nor has one been disclosed in the prior art.
It is an object of this invention to provide an improved holder for earrings for use in the home. It is another object to provide a holder for earrings in which the earrings are easily pinned to a fabric. Still other objects will become apparent from the more detailed description which follows.


Interests in energy storage technologies have been increasingly higher recently. As applications are expanded to energy of mobile phones, camcorders and notebook PCs, and furthermore, to electric vehicles, efforts on the research and development of electrochemical devices have been more and more materialized.
Electrochemical devices are fields receiving most attentions in such aspects and among these, development of secondary batteries capable of charge and discharge have been the focus of attention, and in developing such batteries, research and development on the design of new electrodes and batteries for enhancing capacity density and energy efficiency have been recently progressed.
Among currently used secondary batteries, lithium secondary batteries developed in early 1990s have received attentions with advantages of having high operating voltage and significantly higher energy density compared to conventional batteries such as Ni-MH, Ni—Cd and sulfuric acid-lead batteries using an aqueous liquid electrolyte.
A lithium secondary battery has a structure of an electrode assembly including a positive electrode, a negative electrode and a separator interposed between the positive electrode and the negative electrode being laminated or wound, and is formed by embedding the electrode assembly in a battery case, and injecting a non-aqueous liquid electrolyte thereinto. The lithium secondary battery produces electric energy through oxidation and reduction reactions occurring when lithium ions are intercalated/deintercalated in the positive electrode and the negative electrode.
In a common lithium secondary battery, a negative electrode uses lithium metal, carbon and the like as an active material, and a positive electrode uses lithium oxides, transition metal oxides, metal chalcogen compounds, conductive polymers and the like as an active material.
Among these, a lithium secondary battery using lithium metal as a negative electrode mostly attaches lithium foil on a copper current collector, or uses a lithium metal sheet itself as an electrode. Lithium metal has low potential and high capacity, and has received much attention as a high capacity negative electrode material.
When using lithium metal as a negative electrode, electron density non-uniformization may occur on the lithium metal surface when operating a battery due to various reasons. As a result, a branch-shaped lithium dendrite is produced on the electrode surface causing formation and growth of projections on the electrode surface, which makes the electrode surface very rough. Such lithium dendrite causes, together with battery performance decline, separator damages and battery short circuits in severe cases. As a result, a temperature in the battery increases causing a risk of battery explosion and fire.
In order to resolve such problems, researches such as introducing a polymer protective layer or an inorganic solid protective layer to a lithium metal layer, increasing a concentration of a salt of a liquid electrolyte, or using proper additives have been urgently required.


The present invention relates to an artificial cardiac valve.
Numerous artificial cardiac valves employing flap valve devices of the ball, disc or flap type in the form of a hemi-disc, already exist.
This is the case, for example, of the valves described in Patent Applications EP 0 176 337 (CARBOMEDICS INC.), EP 0 023 797 (HEMEX INC.), EP 0 039 217 (MITRAL MEDICAL INTERNATIONAL, INC. and EP 0 050 971 (HEMEX INC.).
Furthermore, GB 2 084 299 (HEMEX INC.) describes a cardiac valve comprising an annular element and a flap pivotally lodged inside said element as well as linking elements adapted to cooperate with guiding and restraining means provided on the internal lateral wall of the annular element.
These documents describe in particular valves of the type comprising a flap with single pivoting disc. The disc in question pivots by means of hinges in the form of protuberances disposed on the inner wall of the body of the valve and which, due to their configurations and arrangements, are capable of provoking phenomena of thrombosis.
Furthermore, these valves are in a position of complete opening only when the flap has pivoted through a certain angle which is always less than 90.degree. about an axis of rotation which merges with its diameter. In fact, the limited angle of 90.degree. does not allow passive closure of the valve. Consequently, in the position of opening, half of the disc constituting the flap is engaged in the aorta, which may raise problems of flow and/or space requirements.
Moreover, it is observed that these valves tend to oscillate due to the great distance between the axis of rotation and the most remote end of the flap.