A continuous precursor fiber bundle for manufacture of carbon fibers comprising a plurality of precursor fiber bundles each of which comprises at least 30,000 filaments, having a joined portion formed by joining at the terminal end of one of the precursor fiber bundles and the starting end of another one of the fiber bundles directly or through an intervening fiber bundle comprising a plurality of filaments, wherein the individual filaments at the joined portion are substantially uniformly interlaced with each other and wherein the interlacing of filaments is in a pattern selected from the group consisting of continuous substantially uniform interlacing in the transverse direction of said fiber bundles, interlacing at many joints on the joining portion, and interlacing of the entire face of said joining portion.

The present invention relates to a precursor fiber bundle for manufacture of carbon fibers, a production apparatus thereof, and a method for manufacturing a carbon fiber bundle. Particularly, the present invention relates to a series of precursor fiber bundles for manufacture of carbon fibers, composed of at least two fiber bundles each of which comprises 30,000 or more filaments and which fiber bundles are joined each other at the terminal end of one and the starting end of the other one directly or through an intervening fiber bundle, a production apparatus thereof, and a method for manufacturing a carbon fiber bundle using the series of precursor fiber bundles for manufacture of carbon fibers. The series of precursor fiber bundles for manufacture of carbon fibers is stabilized to make a stabilized fiber bundle which is further carbonized to make a carbon fiber bundle.
Carbon fibers have been used as reinforcing materials of aircraft and sporting goods. Recently, carbon fibers begin to be used also as architectural and civil engineering materials and reinforcing materials for members of energy related apparatuses, and such demands are growing rapidly. To meet these demands and furthermore to further increase the demands, carbon fibers having at least conventional properties and less expensive than the conventional carbon fibers are being demanded.
To supply less expensive carbon fibers to the market, the production cost of carbon fibers must be lowered. One method for reducing the cost is to heat-treat (stabilizing and carbonizing) a precursor fiber bundle for manufacture of carbon fibers which fiber bundle has far more filaments than before, for improving the productivity of carbon fibers.
However, if the number of filaments in a precursor fiber bundle increases, i.e., if the filament density becomes higher, heat accumulation in the precursor fiber bundle during stabiizing treatment performing in an oxidizing atmosphere (air) tends to be large. As a result, the filaments are likely to generate heat, and the oxidation reaction of filaments in the stabilizing treatment tends to run away.
So, where the filament density is higher, the stabilizing temperature in the stabilizing treatment must be set at a level lower than that in the stabilizing treatment of a precursor bundle having lower filament density, to take a longer time for the stabilizing treatment, in order to prevent the filament breaking due to the runaway reaction.
However, if the stabilizing treatment temperature is lowered greatly, the stabilizing treatment time becomes too long, and it can happen that the productivity of stabilizing treatment is not improved even though the filament density is higher.
On the other hand, the stabilizing treatment process comprises the steps of continuously supplying a series of precursor fiber bundles from the inlet of a stabilizing treatment furnace into the furnace, stabilizing it in the furnace, to produce a stabilized fiber bundle, and continuously taking out the stabilized fiber bundle from the outlet of the furnace. The precursor fiber bundle continuously supplied into the stabilizing treatment process must be a series of precursor fiber bundles formed by joining a plurality of precursor fiber bundles at the terminal end of one and the starting end of another, each of which bundles is wound around bobbins or spools or contained in cans with a certain limited length.
However, where precursor fiber bundles having a high filament density are simply joined each other, the filament density at the joined portion becomes very higher than the filament density at the other portions (main bundle portions). Simply, the filament density becomes double. Therefore, in the stabilizing treatment, the oxidation reaction of filaments at the joined portion tends to run away compared to the main bundle portion.
A method for splicing or joining precursor bundles is described in Japanese Patent Publication (Kokoku) No. 53-23411. In this method, precursor fiber bundles are spliced each other at the mating ends into a series of precursor fiber bundles, and the series of precursor fiber bundles are treated to be stabilized. Then, the joining portion of the series of stabilized fiber bundles is cut off and removed, and each of the bundles are re-spliced into a series of stabilized fiber bundles and treated to be carbonized.
Japanese Patent Laid-Open (Kokai) No. 54-50624 describes a method of applying a flame resistant compound such as silicone grease to the joining portions.
Furthermore, Japanese Patent Laid-Open (Kokai) No. 56-37315 describes a method comprising heat-treating the ends (the starting end and the terminal end) of precursor fiber bundles and then the precursor fiber bundles are spliced each other by a specific splicing method.
Moreover, Japanese Patent Laid-Open (Kokai) No. 58-208420 describes a method for interlacing the terminal end of one precursor fiber bundle and the starting end of another precursor fiber bundle by a high speed fluid.
However, in any of these methods, since the filament density at the joining portion becomes very higher than that of the main bundle portion, burning, breaking, etc. of filaments are likely to be caused by the heat accumulation during stabilization treatment.
Japanese Patent Publication (Kokoku) No. 60-2407 describes intervening stabilized fibers or carbon fibers at the splicing portion for inhibiting the heat accumulation. However, since the square knot is used for the joining portion, the knot is tightened and the filament density becomes higher. So, the heat accumulation inhibiting effect is small.
As a method for improving these disadvantages, Japanese Patent Publication (Kokoku) No. 1-12850 describes interlacing precursor fiber bundles with each other or interlacing a precursor fiber bundle with a stabilized fiber bundle.
FIG. 1 is a perspective view showing an example of the method. In this method, the mating ends 2a and 2b of the fiber bundles to be joined are simply overlaid in the form of the bundles as they are, inserted into an interlacing treatment chamber 4 of a fluid interlacing nozzle 1, relaxed by about 5 to 60%, and treated by a high speed fluid jetted from two nozzle holes 3 for interlacing the filaments at both ends 2a and 2b with each other. The method for joining with an intervening of a stabilized fiber bundle has an effect that the heat accumulation at the joining portion makes small compared to the direct joining of precursor fiber bundles since the stabilized fibers little generate heat in the stabilizing process.
As for the fluid interlacing nozzle used in this conventional method, as shown in FIG. 1, the high speed jets injected from the two nozzle holes 3 installed in the small entangling treatment chamber 4 collide with each other in the interlacing treatment chamber 4, to produce turbulent flow which opens the fiber bundles for interlacing the filaments with each other. This method is effective for fiber bundles small in the number of filaments constituting them.
However, if the number of filaments constituting each of the fiber bundles to be joined is very large, the jets injected from the nozzle holes do not hit all the filaments of the fiber bundles, and the fiber bundles are not interlaced at filament level and it remarkably happens interlacing between sub-bundles of filaments each other. Such interlaced sub-bundles of filaments occur unevenly at the joining portion and portions with high filament densities are locally formed, and heat is likely to be accumulated there.
An interlacing based on several interlaced sub-bundles of filaments is weak in joining strength since interlacing strength between filaments is weak. The examples described in Japanese Patent Publication (Kokoku) No. 1-12850 disclose only fiber bundle comprising up to 12,000 filaments. If precursor fiber bundles each of which comprises 30,000 or more filaments handling in the present invention are joined at their mating ends directly or through an intervening stabilized fiber bundle according to the known method, breakage of filaments and burning out of filaments due the accumulation of heat occur for the reasons described above.
In addition, in the case of precursor fiber bundles having a high filament density, as the case may be, it may be necessary to impart crimps to the fiber bundles for intensifying the integrity between filaments for better handling convenience in continuously taking out the bundles from their stored condition. Since the crimped fiber bundles are bulky and have their filaments slightly entangled with each other, it is difficult to join the mating ends of the crimped precursor fiber bundles by using the method described in Japanese Patent Publication (Kokoku) No. 1-12850.
That is, even if crimped fiber bundles are overlaid and treated by a high speed fluid, the fiber bundles cannot be sufficiently opened compared to noncrimped fiber bundles since they are crimped. Furthermore, being crimped, the fiber bundles are bulky, cottony and likely to be inhibited in the movement of filaments, and interlacing at filament level is not sufficient compared to non-crimped fiber bundles. Therefore, compared to non-crimped fiber bundles, the filaments are less uniformly entangled with each other at the joining portion, and the joining strength at the joined portion becomes low.
In view of the above problems, the object of the present invention is to provide a continuous precursor fiber bundle for manufacture of carbon fibers, comprising two thick fiber bundles respectively having 30,000 or more filaments and joined each other at their mating ends directly or through an intervening fiber bundle, with the filaments of both the fiber bundles interlaced with each other at the joined portion, and also to provide a production apparatus thereof.
Another object of the present invention is to provide a method for manufacturing a carbon fiber bundle comprising stabilizing the continuous precursor fiber bundle and further carbonizing.
The precursor fiber bundle for manufacture of carbon fibers, the production apparatus thereof, and the method for manufacturing a carbon fiber bundle using the precursor fiber bundle, respectively of the present invention to achieve the above objects are as follows.
The following inventions A1 through A6 are included in the precursor fiber bundle for manufacture of carbon fibers of the present invention respectively.
Invention A1
A precursor fiber bundle for manufacture of carbon fibers, comprising a first precursor fiber bundle for manufacture of carbon fibers, having 30,000 or more filaments, a second precursor fiber bundle for manufacture of carbon fibers, having 30,000 or more filaments, and an intervening fiber bundle comprising many filaments having non-exothermic property at stabilizing treatment temperature, wherein the terminal end of said first fiber bundle and the starting end of said second fiber bundle are joined through said intervening fiber bundle; and at a first joined portion where the terminal end of said first fiber bundle and the starting end of said intervening fiber bundle are joined and at a second joined portion where the starting end of said second fiber bundle and the terminal end of said intervening fiber bundle respectively, the filaments in the respective fiber bundles are substantially uniformly interlaced with each other.
Invention A2
A precursor fiber bundle for manufacture of carbon fibers according to A1, wherein the intervening fiber bundle comprises a stabilized fiber bundle.
Invention A3
A precursor fiber bundle for manufacture of carbon fibers according to A2, wherein a relation of 0.4xc3x97Gxe2x89xa6Fxe2x89xa61.5xc3x97G is satisfied where F is the number of filaments of the stabilized fiber bundle and G is the number of filaments of each of the precursor fiber bundles for manufacture of carbon fibers.
Invention A4
A precursor fiber bundle for manufacture of carbon fibers according to any one of A1 through A3, wherein the filaments of each of the precursor fiber bundles for manufacture of carbon fibers have crimps and the crimps are removed at the joined portions.
Invention A5
A precursor fiber bundle for manufacture of carbon fibers, comprising a first precursor fiber bundle for manufacture of carbon fibers, having 30,000 or more filaments and a second precursor fiber bundle for manufacture of carbon fibers, having 30,000 or more filaments, wherein the terminal end of said first fiber bundle and the starting end of said second fiber bundle are directly joined, and the filaments in the respective fiber bundles are substantially uniformly interlaced with each other at a joined portion where the terminal end of said first fiber bundle and the starting end of said second fiber bundle are joined.
Invention A6
A precursor fiber bundle for manufacture of carbon fibers according to A5, wherein said filaments of each of the precursor fiber bundles for manufacture of carbon fibers have crimps, and the crimps are removed at the joined portion.
The following inventions B1 through B6 are included in the apparatus for producing the precursor fiber bundle for manufacture of carbon fibers of the present invention respectively.
Invention B1
An apparatus for producing a precursor fiber bundle for manufacture of carbon fibers, comprising
(a) a first fiber bundle holding means for holding the flatly opened terminal end of a first precursor fiber bundle for manufacture of carbon fibers, having 30,000 or more filaments, in the transverse direction of the terminal end, at least at two positions apart from each other in the longitudinal direction,
(b) a second fiber bundle holding means for holding the flatly opened starting end of a second precursor fiber bundle for manufacture of carbon fibers, having 30,000 or more filaments, in the transverse direction of the starting end, at least at two positions apart from each other in the longitudinal direction,
(c) an intervening fiber bundle holding means for holding the flatly opened starting and terminal ends of an intervening fiber bundle comprising many filaments having non-exothermic property at stabilizing treatment temperature, in the transverse direction of the starting and terminal ends, at least at two positions apart from each other in the longitudinal direction,
(d) a first interlacing treatment means for interlacing the filaments each other at the terminal end of said first fiber bundle and the starting end of said intervening fiber bundle, and
(e) a second interlacing treatment means for interlacing the filaments each other at the starting end of said second fiber bundle and the terminal end of said intervening fiber bundle, wherein
(f) said first fiber bundle holding means and said second fiber bundle holding means are provided in such a manner that the tip of the terminal end of said first fiber bundle and the tip of the starting end of said second fiber bundle are subjected to face each other, and
(g) said intervening fiber bundle holding means is provided in such a manner that the intervening fiber bundle is subjected to overlap with said first fiber bundle held by said first fiber bundle holding means and said second fiber bundle held by said second fiber bundle holding means.
Invention B2
An apparatus for producing a precursor fiber bundle for manufacture of carbon fibers according to B1, wherein the first interlacing treatment means and the second interlacing treatment means are filament interlacing treatment means using fluid respectively.
Invention B3
An apparatus for producing a precursor fiber bundle for manufacture of carbon fibers according to B1, wherein the first interlacing treatment means and the second interlacing treatment means are filament interlacing treatment means using a needle punch respectively.
Invention B4
An apparatus for producing a precursor carbon fiber bundle for manufacture of carbon fibers, comprising
(a) a first fiber bundle holding means for holding the flatly opened terminal end of a first precursor fiber bundle for manufacture of carbon fibers, having 30,000 or more filaments, in the transverse direction of the terminal end, at least at two positions apart from each other in the longitudinal direction,
(b) a second fiber bundle holding means for holding the flatly opened starting end of a second precursor fiber bundle for manufacture of carbon fibers, having 30,000 or more filaments, in the transverse direction of the starting end, at least at two positions apart from each other in the longitudinal direction, and
(c) an interlacing treatment means for interlacing the filaments each other at the terminal end of said first fiber bundle and the starting end of said second fiber bundle, wherein
(d) said first fiber bundle holding means and said second fiber bundle holding means are provided in such a manner that said first fiber bundle held by said first fiber bundle holding means and said second fiber bundle held by said second fiber bundle holding means are subjected to overlap with each other.
Invention B5
An apparatus for producing a precursor fiber bundle for manufacture of carbon fibers according to B4, wherein the interlacing treatment means is filament interlacing treatment means using fluid.
Invention B6
An apparatus for producing a precursor fiber bundle for manufacture of carbon fibers according to B4, wherein the interlacing treatment means is filament interlacing treatment means using a needle punch.
The following inventions C1 through C16 are included in the method for manufacturing the carbon fiber bundle of the present invention.
Invention C1
A method for manufacturing a carbon fiber bundle, comprising
(a) a step of overlaying the flatly opened terminal end of a first precursor fiber bundle for manufacture of carbon fibers, having 30,000 or more filaments and the flatly opened starting end of an intervening fiber bundle comprising many filaments having non-exothermic property, and substantially uniformly interlacing the filaments of both of the fiber bundles with each other to form a first joining portion,
(b) a step of overlaying the flatly opened starting end of a second precursor fiber bundle for manufacture of-carbon fibers, having 30,000 or more filaments and the flatly opened terminal end of said intervening fiber bundle, and substantially uniformly interlacing the filaments of both of the fiber bundles with each other to form a second joining portion,
(c) a step of treating to stabilize a continuous precursor fiber bundle for manufacture of carbon fibers formed with said first and second fiber bundles which are joined through said intervening fiber bundle at said first and second joining portions, to obtain a stabilized fiber bundle, and
(d) a step of treating to carbonize said stabilized fiber bundle, to obtain a carbon fiber bundle.
Invention C2
A method for manufacturing a carbon fiber bundle according to C1, wherein the intervening fiber bundle comprises a stabilized fiber bundle.
Invention C3
A method for manufacturing a carbon fiber bundle according to C2, wherein a relation of 0.4xc3x97Gxe2x89xa6Fxe2x89xa61.5xc3x97G is satisfied where F is the number of filaments of the stabilized fiber bundle of the intervening fiber bundle and G is the number of filaments of each of the precursor fiber bundles for manufacture of carbon fibers.
Invention C4
A method for manufacturing a carbon fiber bundle according to any one of C1 through C3, wherein means for forming the first and second joining portions comprise filament interlacing means using fluid respectively.
Invention C5
A method for manufacturing a carbon fiber bundle according to C4, wherein when the first and second joining portions are formed, a density of each of the fiber bundles overlapping to form the first and second joining portions is 4,000 filaments/mm or less.
Invention C6
A method for manufacturing a carbon fiber bundle according to C5, wherein where filaments in the first and second fiber bundles have crimps, the crimps of the filaments at the terminal end of the first fiber bundle and the starting end of the second fiber bundle are removed before forming the first and second joining portions.
Invention C7
A method for manufacturing a carbon fiber bundle according to any one of C1 through C3, wherein means for forming the first and second joining portions comprise filament interlacing means using a needle punch respectively.
Invention C8
A method for manufacturing a carbon fiber bundle according to C7, wherein when the first and second joining portions are formed, a density of each of the fiber bundles overlapping to form the first and second joining portions is 4,000 filaments/mm or less.
Invention C9
A method for manufacturing a carbon fiber bundle according to C8, wherein where filaments in the first and second fiber bundles have crimps, the crimps of the filaments at the terminal end of the first fiber bundle and the starting end of the second fiber bundle are removed before forming the first and second joining portions.
Invention C10
A method for manufacturing a carbon fiber bundle, comprising
(a) a step of overlaying the flatly opened terminal end of a first precursor fiber bundle for manufacture of carbon fibers, having 30,000 or more filaments and the flatly opened starting end of a second precursor fiber bundle for manufacture of carbon fibers, having 30,000 or more filaments, and substantially uniformly interlacing the filaments of both of the fiber bundles with each other to form a joining portion,
(b) a step of treating to stabilize a continuous precursor fiber bundle for manufacture of carbon fibers formed with said first and second fiber bundles which are joined at the joining portion, to obtain a stabilized fiber bundle, and
(c) a step of treating to carbonize said stabilized fiber bundle, to obtain a carbon fiber bundle. Invention C11
A method for manufacturing a carbon fiber bundle according to C10, wherein means for forming the joining portion comprises filament interlacing means using fluid.
Invention C12
A method for manufacturing a carbon fiber bundle according to C10, wherein means for forming the joining portion comprises filament interlacing means using a needle punch.
Invention C13
A method for manufacturing a carbon fiber bundle according to C11 or C12, wherein when the joining portion is formed, a density of each of the fiber bundles overlapping to form the joining portion is 4,000 filaments/mm or less.
Invention C14
A method for manufacturing a carbon fiber bundle according C13, wherein where filaments in the first and second fiber bundles have crimps, the crimps of the filaments at the terminal end of the first fiber bundle and the starting end of the second fiber bundle are removed before forming the joining portion.
Invention C15
A method for manufacturing a carbon fiber bundle according to C13 or C14, wherein after forming the joining portion and before the stabilizing treatment, a stabilization inhibitor is applied to the joining portion.
Invention C16
A method for manufacturing a carbon fiber bundle according to C15, wherein the stabilization inhibitor is boric acid water.
In the present invention, as the filaments constituting the precursor fiber bundles for manufacture of carbon fibers, filaments of an acrylic polymer conventionally used for production of carbon fibers is preferably used.
In the present invention, the filaments constituting the precursor fiber bundles for manufacture of carbon fibers may have crimps or have no crimp. If the filaments have crimps, it is preferable that a crimping degree of each of the filaments is 8 curls/25 mm to 13 curls/25 mm. When a precursor fiber bundle for manufacture of carbon fibers is joined with an intervening fiber bundle or another precursor fiber bundle for manufacture of carbon fibers, it is preferable that the crimps of the filaments are removed at a joining portion of the fiber bundles. It is preferable that a removal of the crimps is achieved by heat-treating the end of the fiber bundle.
In the present invention, the expression that the filaments of the intervening fiber bundle have non-exothermic property at stabilizing treatment temperature means that the calorific value obtained according to the DSC (differential scanning calorimeter) method at the stabilizing treatment temperature is 500 cal/g or less, and the detail will be described later.
As the intervening fiber bundle comprising many filaments having non-exothermic property at the stabilizing treatment temperature, a stabilized fiber bundle subjected to a stabilizing treatment, particularly a stabilized fiber bundle obtained by stabilizing a fiber bundle formed by acrylic polymer filaments at a temperature of 200xc2x0 C. to 350xc2x0 C. in air is preferably used.
In the present invention, the expression that the filaments are substantially uniformly interlaced with each other means that the many filaments constituting one fiber bundle and many filaments constituting another fiber bundle are individually interlaced with each other at single filament level, and does not mean interlacing between one group having several filaments and another group having several filaments.
In the present invention, a filament interlacing treatment means using fluid or a needle punch is preferably used as the filament interlacing treatment means for substantially uniformly interlacing filaments with each other at the joining portion formed between the end (the terminal end or the starting end) of a precursor fiber bundle and the end (the starting end or the terminal end) of an intervening fiber bundle, or at the joining portion formed between the end (the terminal end) of a precursor fiber bundle and the end (the starting end) of another precursor fiber.
It is preferable that the stabilizing treatment temperature for the precursor. fiber bundles for manufacture of carbon fibers in the present invention is 200xc2x0 C. to 350xc2x0 C.
Giving a stabilization inhibitor before stabilizing treatment, to the joining portion in one continuous precursor fiber bundle for manufacture of carbon fibers obtained by directly joining the mating ends of the precursor fiber bundles for manufacture of carbon fibers is intended to prevent burning and breaking of filaments likely to be caused by the heat accumulation at the joining portion during stabilizing treatment. As the stabilization inhibitor, boric acid water is preferably used.

Precursor fiber bundle for manufacture of carbon fiber, manufacturing apparatus and method of manufacturing carbon fiber bundle


A computer-printable adhesive note system configures a computer and a printer to print information on self-sticking adhesive notes. The system includes a note assembly and a plurality of instructions in the form of computer code. The note assembly includes a printing sheet with a strip of pressure-sensitive adhesive applied on one side thereof and covered by a backing sheet. The printing sheet is divided into a plurality of notes by lines of perforations. The plurality of instructions are installed on a computer and may utilize an existing word-processing program on the computer. The plurality of instructions configure the computer to receive, from a keyboard of the computer, information to be printed on the printing sheet of one of the notes of the note assembly. The plurality of instructions then configure the printer to print the received information on the printing sheet of one of the notes of the note assembly.

Adhesive notes, such as Post-its.RTM. Notes produced by Minnesota Mining and Manufacturing (3M), are ubiquitous in homes and offices around the world. The yellow, pink, blue, and fluorescent notes are used for everything from bookmarks to memoranda to labels to phone-message pads.
The great utility of adhesive notes lies in the pressure-sensitive adhesive (PSA) applied in a strip along one edge, which adhesive is of the removable or repositionable type. The PSA strip allows a plurality of sheets, typically about 100, to be adhered together to form a note pad. Individual notes are then written upon, removed from the pad, and adhered to a surface. The notes can then be easily removed, without adhesive remaining behind on the surface, and re-adhered to another surface.
As mentioned, the user writes information on the note in his or her own hand. In many instances it may be desirable to have a more professionally appearing note than that which is achievable with personal penmanship, particularly in a corporate environment. Further, it may be desirable to create "application specific" notes on which a template of information is printed with additional information being printed on the note on a per-use basis. With current adhesive note pads, such professionally appearing or application-specific adhesive notes are not possible.
Avery Dennison Corporation, which is the assignee of the present invention, markets a label-printing system under the name of LabelPro.TM. which enables a user to print information on individual die-cut labels of label sheets. The labels may then be peeled off the label sheet and adhered to files, index dividers, and so on. Although such a label-printing system is useful for generating professionally looking labels, it does not enable a user to print information on adhesive notes.


A halftone screening method creates screens of a plurality of colors, where each of the screens is divided into a plurality of cells, and intentionally changes a dot position of certain colors within cells of the screens of the certain colors relative to a dot position of a reference color within a cell of the screen of the reference color, so as to suppress a color tone change caused by positional errors of the screens.

This application claims the benefit of Japanese Patent Applications No.2001-162682 filed May 30, 2001 and No.2001-232336 filed Jul. 31, 2001, in the Japanese Patent Office, the disclosures of which are hereby incorporated by reference.
1. Field of the Invention
The present invention generally relates to halftone screening methods and storage media, and more particularly to a halftone screening method which uses halftone cells of a rectangular lattice, and a computer-readable storage medium which stores a computer program for causing a computer to process image data according to such a halftone screening method.
2. Description of the Related Art
FIGS. 1A and 1B are diagrams for explaining a conventional scattered dot dither type halftone cell. In FIGS. 1A and 1B, a non-regular hexagonal halftone cell is created by cutting a pair of confronting corners of a square halftone cell into a pair of confronting sloping sides. Since the pair of confronting corners of the square halftone cell made up of 9×9=81 pixels are cut into the pair of confronting sloping sides, the non-regular hexagonal halftone cell is made up of 81−9=72 pixels. FIG. 1A shows a non-regular hexagonal halftone cell C for one color, namely, cyan, and shows a case where 3×3=9 pixels at the central portion are colored to represent a dot C1 having a gradation level "9" with respect to a maximum number "72" of gradation levels.
When centers of halftone dots of each of the colors are arranged at the same pixel position of the halftone screen in a color printer, even a slight error in the positions of the halftone dots of each of the colors on the halftone screen results in a conspicuous change in color tone. FIG. 1B shows a case where a non-regular-hexagonal halftone cell M for magenta is shifted by 1 pixel to the right and 1 pixel to the top with respect to the non-regular hexagonal halftone cell C for cyan, and a non-regular hexagonal halftone cell Y for yellow is shifted by 2 pixels to the right and 1 pixel to the bottom with respect to the non-regular hexagonal halftone cell C for cyan. In this case, even if the 3×3=9 pixels at the central portion of the non-regular hexagonal halftone cell M is colored to represent a dot M1, the 3×3=9 pixels at the central portion of the non-regular hexagonal halftone cell Y is colored to represent a dot Y1, and the dots C1, M1 and Y1 are overlapped, the positions of the dots C1, M1 and Y1 do not match and the change in the color tone is conspicuous.

Halftone screening method and storage medium


An open/close valve construction for use in solid-state fluid transport circuits having discrete fluid passageways formed in rigid substrates with a substrate land between port regions of the fluid passageways. The valve construction comprises a diaphragm disk having a dome portion overlying the substrate land and port regions and having a self-restoring resilience sufficient to maintain its dome configuration against substantial line vacuum. A valve actuator is located above the dome portion and spring biased to compress the dome into a flat configuration closing the port regions. Means for negating the spring force are provided to allow the dome portion to restore its configuration and open the valve.

1. Field of the Invention
The present invention relates to improvements in solid-state fluid circuit systems for effecting controlled transport of liquids and/or gas substances. More particularly, it relates to improved valve structures for selectively providing fluid communication between spaced fluid passageways within such circuit systems.
2. Background Art
In applications where it is necessary to transport and process small quantities of liquid or gas substances in a highly controlled and precise manner, such as in biological liquid analyzers or gas chromatography systems, solid-state fluid circuit systems are gaining in popularity. Such solid-state fluid circuit systems typically comprise a solid plastic plate, usually comprising a laminated structure of two or more plastic plates, having a network of internal passageways for conducting pressurized fluid from one location to another. Various fluid-control devices, i.e. valves, and fluid sensors are located along such passageways to control the movement of the fluid between the passageways and to process the fluid as required. A key component to the effectiveness of any such fluid circuit system is the valving mechanism used to selectively provide a fluid communication between the spaced passageways.
A common approach for constructing valving mechanisms for fluid circuit systems of the above type has been to position a continuous membrane sheet atop a rigid substrate having a planar surface which has been milled-out, chemically etched or otherwise grooved, to define spaced fluid passageways, and to provide means for selectively moving portions of that membrane towards and away from a land portion separating the opposing passageways to respectively prevent and enable fluid communication between the passageways. U.S. Pat. No. 4,304,257 discloses such a valving structure wherein solenoid-operated actuators are affixed to selected portions of such a membrane sheet to mechanically move their respective attached sheet portions towards and away from the land separating spaced passageways. U.S. Pat. No. 5,203,368 discloses a similar valve structure wherein the membrane is pneumatically moved by suction or pressure applied to the side of a continuous sheet membrane that is opposite the fluid flow passageways. U.S. Pat. Nos. 5,083,742 and 5,176,359 disclose a valve mechanism similar to the aforementioned mechanisms, but wherein the membrane sheet is constructed to have a plurality of blister portions that form domes over the lands between spaced fluid passageways. These blister portions have self-restoring forces that normally urge them into their domed condition. Pneumatic actuators are provided for introducing a pressurized fluid into a chamber above each dome in order to flatten the dome into contact with the land between the spaced passageways and thereby disrupt fluid communication between the spaced fluid passageways.
While all of the above-noted valving structures are useful for controlling fluid flow in solid-state fluid circuits of the type described, all suffer significant problems with respect to fluid leakage. This is mainly due to the difficulty in bonding the dissimilar materials that constitute the flexible membrane and the sandwiching or underlying rigid substrates. Such leakage can allow escape of the transported fluid and/or unintended movement of valve elements, due to decreased "holding" pressure on the membrane portions at the open/close region.
U.S. Pat. No. 5,496,009 discloses an approach for avoiding the above-noted leakage problems. Rather than using a single flexible membrane that encompasses the entire surface area of a pair of confronting plates that cooperate to define a network of fluid passageways along which multiple valves are positioned, this approach uses a plurality of discrete flexible diaphragm disks. Each diaphragm disk is positioned within one of a plurality of small valve chambers formed in one of the plates, each valve chamber containing a pair of spaced fluid ports which, by virtue of the valve structure, are to be selectively fluidically connected. The peripheral edge of each disk is sandwiched between the confronting plates to hold the disk in a position overlying the ports. A control port is provided through one plate to access that side of the diaphragm that is opposite the fluid ports, and the diaphragm is moved towards and away from the fluid ports, to respectively close and open fluid communication therebetween, by application of positive or negative pressure to the control port. Since the surface area of each disk is only slightly larger than the respective surface area of the valve chambers, the disks themselves do not significantly interfere with the lamination process of bonding the plates together; thus, the aforementioned leaking of fluid is minimized. While this device is improved significantly with respect to inter-substrate leakage, it is disadvantageous in that it relies upon a pneumatic pressure differential to control movement of a flexible diaphragm member; this presents a problem in maintaining the valve closed over an extended period against positive pressure fluids in the transport passage. Affixing a mechanical actuator to such a thin compliant member would present bonding/attachment difficulties and would be contrary to the patentee's design approach, which is to provide a flexibly conforming seal construction at the diaphragm/flow passage interface. Further, there is still an opportunity for fluid to leak past the edges of the diaphragm disk and into the control port used to deflect the diaphragm disk.

Fluid transport circuit and valve structure therefor


An apparatus for removal bones from a fish fillet is presented. A conveyor is provided for conveying the fish fillet and supporting means is arranged on said conveyor for supporting the fish fillet as it is being conveyed by means of imposing the fish fillet on it so that the bones to be removed are exposed. A second supporting means is arranged sidewise to said first supporting means for maintaining the fish fillet in a fixed position as the exposed bones are removed with a bone removal unit, which is arranged above the conveying means.

One of the main concerns for fish processors is unwanted bones in fish fillet, such as whitefish in particular cod. Beside that such bones make the fish product less attractive it can have devastating effect if they are swallowed. This can have negative publicity, which may lower the value of the product. Therefore it should not surprise anyone that fish producers all over the world spent much effort in finding bones and removal them. This is and been very labour consuming operation, where some of the bones are difficult to find and to remove. In some cases a part of the fish fillet must be removed due to difficulties in removal the bones.
Apparatus for processing fish exist. In U.S. Pat. No. 5,525,101 a device is described for removal bones from fish meat. This device is however hand-held device, which means that the processing in operating the fish product is mainly controlled by the worker. Further this it is a demanding job to hold the device in hand with its electrical power supply. As the device is hand-held the possibilities to automate the process are very limited.
From a Danish utility Model DK 1999 00226 U4 an apparatus is presented for bone removal, where the apparatus is hinged to a frame above a conveyor. The bone-removal unit is then elevated semi- or fully automatically toward the upwardly facing surface of the fish filets and driven over the entire surface. The problem with this method is that the entire surface is brought into contact with the bone-removal unit, which can damage the fish fillet.
An improved apparatus and method for removal bones is presented in WO 01/43553, that comprises a conveyor and a bone-removal unit hinged above the conveyor, where the bone removal unit is movable in an approximated up-and downward direction toward the conveyor. The conveyor comprises an upwardly extending edge and a plurality of elevating means forming a horizontal support for the fish fillet there in-between for elevating a particular area of the fillet. On the outside of said elevating means a pressure means or device is provided to maintain the fish in a fixed position. The bones are removed by bringing the removal units into contact to that particular area to that are primarily located in the horizontal surface.
The main problem in WO 01/43653 is that the bones to be removed are not sufficiently exposed because of the horizontal support for the bone-removal unit, which may result in that some bones are left in the fish after the processing. Also, the movement of the bone-removal unit is limited to only up-and downward movement, and therefore bones that are not in the plane of the bone removal unit remain in the fish fillet. Further, the pressure means that is provided for maintaining the fish fillet in a fixed position may be reduced to the interval where the bones removal procedure is running, which would simplify the apparatus significantly.


Fiber optic backlighting substrates having a predetermined shape are manufactured by a special rotating fixture having a deep, narrow peripheral groove in which several windings of the fiber may be stacked on top of one another, to provide a closely packed spiral array having a thickness on the order of one fiber diameter and a radial extent equal to several times the diameter of a single fiber thick and several fibers wide. At least one wall of the groove is preferably hinged or otherwise removable, to provide convenient access to the spiral and to permit it to be removed from the fixture, whereupon the spiral may be cut radially to form a fiber optic substrate comprising a flat array of closely packed curved fibers, from which extends one or more bundles of loose fibers. By providing a cam-shaped groove having a non-constant depth relative to the rotational axis of the fixture, fiber arrays having segments of varying radii may be fabricated.

Fiber optic backlighting panels are commonly used to illuminate a high contrast image that is visible even under poor ambient light.
Typically, such prior backlighting devices utilize a plurality of optical fibers, each having a core surrounded by cladding, which are placed adjacent one another above an optically reflecting surface. Light is beamed into the optical fibers from a light source, such as a lamp. The light is propagated in the core of the optical fiber by means of partial internal refraction, and exits at one or more discontinuities in the fiber, providing local illumination in the region of the discontinuity.
In the past, such fiber optic backlighting devices have been manufactured from fiber optic substrates comprising one or more optical fibers grouped together in a rectangular ribbon or panel substrate configuration. Typically, the ribbon or panel substrate is about 0.01 to 0.03 thick. By deforming (for example, by a heated die) or machining (for example, by a computer-controlled laser beam) at least one surface of the substrate, local discontinuities are formed in at least some of the fibers at which some or all of the light introduced into one or both ends of the fiber will exit. Such illumination may be utilized for backlighting a variety of displays.
Analog indicators in automotive and other applications, such as speedometers, fuel level indicators, dial gauges, and the like, are traditionally arranged in the form of a circular annulus, or an angular segment of an annulus. In theory, such indicators can be backlit with one or more rectangular panels covering the entire area. However, backlighting the entire area of an annular indicator is inefficient and interferes with the use of the area in the middle or the corners of the display for other devices and mechanisms, such as a self-contained digital readout.
For such applications, it is thus desirable to use fiber optic illumination ribbons and panels having a curved shape. To date such curved shapes have been laid up one strand at a time, using a flat template defining the desired shape. Thus a need exists for a method and apparatus for the mass production of arrays of optical fibers that is not limited to rectangular panels and ribbons.

Method and apparatus for making arbitrarily shaped fiber optic backlighting substrates


A method and apparatus for calculating the volume fraction of carbon in the fly ash using a carbon in fly ash sensor that has a resonant cavity. The method first determines the volume fraction of ash in the fly ash. The method then determines the real and imaginary components of the dielectric constant of a mixture of pure carbon and pure fly ash, and the transmission factor of a signal from the oscillator in the sensor transmitted through the cavity due to absorption by material in the cavity. The method then determines the volume fraction of carbon in the fly ash by using the volume fraction of ash, the real and imaginary components of the pure mixture dielectric constant, the absorption transmission factor and the length of the cavity, the speed of light and the frequency of the oscillator.

This invention relates to sensors that measure the Carbon content of the fly ash produced by the combustion process in a pulverized coal-fired steam generator and more particularly to the calculation of the carbon content sensed by such a sensor.
Fly ash results from the incomplete combustion of pulverized coal in a pulverized coal-fired steam generator. The fly ash is the combination of inert and inorganic residue resulting from the incomplete combustion of the pulverized coal. The pulverized coal contains varying amounts of carbon or coke particles. In general, the inorganic ash particles consist primarily of silicates, oxides and sulfates, together with small quantities of phosphates and other trace compounds.
The presence of unburned Carbon in boiler fly ash has important economic and environmental consequences to the operator of a coal-fired boiler installation. Its presence is a measure of inefficient fuel utilization which means that more fuel must be burned in order to obtain a given output and which in turn directly increases the cost of electrical power generation. Furthermore, inefficient fuel utilization by virtue of requiring more fuel to be burned in order to produce a given output increases the presence of NOx emissions which is the basis for environmental concerns. Thus, knowledge of the Carbon content of boiler fly ash is an important element in establishing a low NOx boiler emission strategy.
In addition, low Carbon fly ash can be a potential source of income to the operator of a pulverized coal-fired boiler in that fly ash can be employed as a building material if the Carbon content in the fly ash is sufficiently low. Fly ash with a high Carbon content is unsuitable as a building material and normally requires the use of expensive waste disposal methods.
One system for continuous in-situ measurement of Carbon in fly ash is described in U.S. Pat. No. 5,729,470 (xe2x80x9cthe ""470 Patentxe2x80x9d) which is assigned to the same assignee as the present invention. The system described in the ""470 Patent includes a resonant cavity for measuring in-situ and in real time the Carbon content of the fly ash.
Referring now to FIG. 1 (which is FIG. 5 of the ""470 Patent), there is shown the resonant cavity 300 in the system of the ""470 Patent. Also shown in FIG. 1, are intelligence 100, transmitting section 200 and receiving section 400 of the system of the ""470 Patent. As is shown in FIG. 2 herein (which is FIG. 3 of the ""470 Patent), intelligence 100 includes a CPU 112.
Returning once again to FIG. 1, the transmitting section 200 includes a pressure boundary 202, an oscillator 204, a signal coupler 208, a reference detector 210, a signal isolator 214 and a waveguide 216.
The transmitting section 200 further includes a first air purge 218 and a second air purge 220.
The cavity section 300 is comprised of a first concave spherical mirror 302, a second concave spherical mirror 304, a common optical axis 306, a plurality of alignment screws 308, an inspection volume 300xe2x80x2, a first annular ring 302xe2x80x2 and a second annular ring 304xe2x80x2. As is shown in FIG. 3 (which is FIG. 6 of the ""470 Patent) the first and second concave spherical mirrors 302, 304 each contain a pattern of circular holes that are drilled therethrough that consist of a central hole 310, so located as to be on the optical axis 306, which is common both to the first concave spherical mirror 302 and the second concave spherical mirror 304 and an array of planetary holes 312 symmetrically located about the central hole 310.
As is shown in FIG. 4 (which is FIG. 7 of the ""470 Patent) the first and second concave spherical mirrors 302, 304 have attached to their nonreflecting sides three screws 308 symmetrically located about the center of the mirrors 302, 304 for the purpose of aligning said mirrors 302, 304 along the common optical axis 306. Two of three alignment screws 308 for each of mirrors 302, 304 are turned by an associated stepper motor (not shown in FIG. 1).
The receiving section 400 includes a pressure boundary 402, a waveguide 404 and a signal detector 408. The receiving section 400 further includes a first air purge 412 and a second air purge 414.
The oscillator 204 receives as input the electrical drive signal 104 originating from the intelligence section 100. The oscillator 204 typically may take the form of a free running biased tuned microwave oscillator, the nature of the construction and the mode of operation of which is known and understood by those skilled in the art. As a consequence of the input received thereby, the oscillator 204 generates as output a constant amplitude, sinusoidal signal 206 of electromagnetic radiation which repeatedly sweeps through a certain frequency span, xcex94f.
The oscillator output signal 206 is supplied in known fashion to the signal coupler 208. Again in known fashion, a small fraction 206xe2x80x2 of the oscillator output signal 206 is diverted by the signal coupler 208 to the reference detector 210, to be described hereinafter, and the remainder 206xe2x80x3 of the oscillator output signal 206 is supplied to the waveguide 216 via the signal isolator 214. Typically the signal isolator 214 may take the form of a waveguide section filled with a ferrite material so aligned that in combination with the magnetic field of a permanent magnet, electromagnetic radiation can propagate in one direction only. The purpose of the signal isolator 214 is to prevent signal return from the cavity section 300. Since reflected energy is sharply attenuated by the signal isolator 214 it helps ensure the frequency and amplitude stability of the oscillator 204.
The detector 210 is designed to receive as input the signal 206xe2x80x2 which is delivered from the signal coupler 208 in the form of electromagnetic radiation and whose power is a small fraction of the oscillator signal 206 power. The reference detector 210 typically may take the form of a full wave rectifier which may or may not be followed by a peak detector. The reference detector 210 is operative upon the input signal 206xe2x80x2 in a known manner in order to thereby generate as output a reference signal 212 in the nature of a DC voltage proportional to the power of the input signal 206xe2x80x2 that is supplied to the reference detector 210.
The signal 206xe2x80x3 in the form of electromagnetic radiation is supplied as an input to the waveguide 216 which, in accordance with the best mode embodiment of the invention, is rigidly fixed to the non-reflecting side of the first concave spherical mirror 302 so as to be aligned along the common optical axis 306. The waveguide 216 in turn is designed so as to be operative to deliver the signal 206xe2x80x3 to the cavity section 300 via the central hole 310 which is illustrated in FIG. 3. The waveguide 216, in accordance with the best mode embodiment of the invention, is preferably equipped with a first air purge 218. The air purge 218 is designed to be operative so as to direct an external source of pressurized air 218xe2x80x2 into and along the waveguide 216 through to the cavity section 300 via the central hole 310 depicted in FIG. 3. Such purging activity helps prevent fouling of the mirror 302 and the waveguide 216 which might otherwise occur due to fly ash buildup.
The transmitting section 200 includes a pressure boundary 202. The pressure boundary 202 may or may not enclose the oscillator 204, the signal coupler 208, the reference detector 210 and the signal isolator 214. The pressure boundary 202 coupled with the first spherical mirror 302 and an annular ring 302xe2x80x2 concentric with the mirror 302 is intended to define a volume 202xe2x80x2 which undergoes purging similar to that which has been described above. Such purging directs an external source of pressurized air 220xe2x80x2 into the aforesaid volume 202xe2x80x2 through to the cavity section 300 via the annular ring 302xe2x80x2 and the planetary holes 312 shown in FIG. 3. The purging activity helps prevent fouling of the mirror 302 which might otherwise occur due to fly ash buildup.
The cavity section 300 includes the first concave spherical mirror 302 and the second concave spherical mirror 304, each aligned along the common optical axis 306 and so oriented that their reflective sides face one another. For purposes of the description thereof the cavity section 300 further is considered to encompass the approximately cylindrical inspection volume 300xe2x80x2 subtended by the concave spherical mirrors 302, 304, as the latter are separated by a fixed distance, L, along the common optical axis 306, and an imaginary boundary not shown in FIG. 1 but shown in FIG. 9 of the ""470 Patent delimited by the beam spot size, w(z). It is through and across this inspection volume 300xe2x80x2 that the flue gas stream 28 is made to flow, carrying with it boiler fly ash.
As described hereinabove, the sinusoidal signal 206xe2x80x3 of electromagnetic radiation is supplied to the cavity section 300 from the transmitting section 200 via the waveguide 216. The signal 206xe2x80x3 enters the inspection volume 300xe2x80x2 from the center hole 310 depicted in FIG. 3. The signal 206xe2x80x3 propagates through the inspection volume 300xe2x80x2 to the second concave spherical mirror 304 and is reflected back to the first concave spherical mirror 302 to be reflected once again back to the second concave spherical mirror 304. To this end the signal 206xe2x80x3 is reflected back and forth between the two spherical mirrors 302, 304 numerous times. The resulting steady state signal 206xe2x80x3 is captured by the second concave spherical mirror 304 at the center hole 310 shown in FIG. 3. The signal 206xe2x80x3 is then delivered by way of the waveguide 404 to the signal detector 408. The waveguide 404, in accordance with the best mode embodiment of the invention, preferably is rigidly fixed to the non-reflecting side of the second concave spherical mirror 304 so as to be aligned along the common optical axis 306.
The signal detector 408 receives as input, from the cavity section 300, the signal 206xe2x80x3 that is in the form of electromagnetic radiation. Typically the signal detector 408 may take the form of a full wave rectifier which may or may not be followed by a peak detector. The signal detector 408 is operative upon the input signal 206xe2x80x3 in known fashion to provide as an output therefrom, a cavity signal 410 which is in the nature of a DC voltage that is proportional to the power of the input signal 206xe2x80x3 to the signal detector 408. The cavity signal 410 then functions as one input to the intelligence section 100.
It is further seen from reference to FIG. 1 that the receiving section 400 includes a pressure boundary 402. The pressure boundary 402 may or may not enclose the signal detector 408. The pressure boundary 402 coupled with the second concave spherical mirror 304 and an annular ring 304xe2x80x2, concentric with the second concave spherical mirror 304, define a volume 402xe2x80x2 which, preferably in accordance with the best mode embodiment of the invention, undergoes purging from an external source of pressurized air 414xe2x80x2 similar to that which has been described hereinabove, with respect to the transmitting section 200. Furthermore, the waveguide 404 that directs the captured signal 206xe2x80x3 to the signal detector 408 also, preferably in accordance with the best mode embodiment of the invention, undergoes a purging process from an external source of pressurized air 412xe2x80x2 similar to that which has been described hereinabove, with respect to the transmitting section 200. Such purging helps prevent fouling of the mirror 304 and waveguide 404 as a result of fly ash buildup, which might otherwise occur.
The component elements of the resonant cavity are affixed to the rear gas pass of the pulverized coal-fired steam generator by rigidly fixing the pressure boundaries 202, 402 by any type of conventional means suitable for use for such purpose, to the opposing walls of the rear gas pass at nearly the same elevation. The first and second concave spherical mirrors 302, 304 of the cavity section 300 are in turn mounted to the pressure boundaries 202, 402 via the alignment screws 308 so as to be capable of mutual alignment along the common optical axis 306 by way of the alignment screws 308. It should be noted that the first and second concave spherical mirrors 302, 304 are not affixed directly to the walls of the rear gas pass.
As the transmitted signal 206xe2x80x3 is swept through its frequency span, xcex94f, and reflected back and forth between the mirrors 302, 304, one or more cavity resonances may be excited. The resonances are typified by repetitive, sharp peaks in the power of the transmitted signal 206xe2x80x3 detected at the receiver 408. A resonance profile representative of resonant cavities is shown in FIG. 5 (which is FIG. 8 of the ""470 Patent). Such a data profile is presented to the central processing unit 112, via the data signal(s) 110. As is described in the ""470 Patent, the purpose of CPU 112 is to process the signals 110 to thereby characterize any resonances excited within cavity 300.
The ""470 Patent describes the use of a calibration curve so that the carbon loading can be obtained from the peak amplitude A of the signal received at receiver 408. The curve is generated by comparing known samples to peak amplitude and since the curve is nonlinear it has proven difficult to generate accurately in practice. Further the system of the ""470 Patent uses free spectral range to measure ash loading which is not easy to obtain from a microwave system. The method of the present invention solves overcomes these problems.
The present invention is a method for determining the volume fraction of carbon of fly ash using a sensor that has a resonant cavity that is excited by an oscillator. The method has the steps of:
a) calculating the volume fraction of ash Vfash in the fly ash; and
b) calculating the volume fraction of carbon in fly ash from:   Vfcarbon  =                    -        b            ±                                    b            2                    -                      4                                      (                              a                                                  xe2x80x83                                                c                            )                                                  2                              (          a          )                2
xe2x80x83where       a    =                  (                                            -              2                                    π                                      xe2x80x83                                                  Lf                                            (                Vfash                )                                                                ϵ              xe2x80x3                                    carbon                                C                                      (                              ln                                                  (                  Ta                  )                                            )                                      )            2            b    =          Vfash                    (                                            ϵ              xe2x80x2                                    ash                    -                                    ϵ              xe2x80x2                                    carbon                          )                  c    =          (                        -                      Vfash                                      (                                                ϵ                                      xe2x80x2                                                              xe2x80x83                                                                                ash                            )                                      -                  1          xe2x80x2                    )
and L is the length of the resonant cavity, C is the speed of light in meters per second and f is the frequency of the oscillator.
The present invention is also an apparatus for determining the volume fraction of carbon of fly ash using a sensor that has a resonant cavity that is excited by an oscillator. The apparatus has:
a) a digital processor; and
b) a routine executed by the digital processor for:
(i) calculating the volume fraction of ash Vfash in the fly ash; and
(ii) calculating the volume fraction of carbon in fly ash from:
c)   Vfcarbon  =                    -        b                          +        _                                                b            2                    -                      4                                      (              ac              )                                                  2                              (          a          )                2
xe2x80x83where   a  =            (                                    -            2                              π                                xe2x80x83                                          Lf                                      (              Vfash              )                                                      ϵ            xe2x80x3                              carbon                          C                                (                          ln                                            (                Ta                )                                      )                              )        2  xe2x80x83b=Vfash(xcex5xe2x80x2 ashxe2x88x92xcex5xe2x80x3 carbon)
c=(xe2x88x92Vfash(xcex5xe2x80x2 ash)xe2x88x921xe2x80x2)
and L is the length of the resonant cavity, C is the speed of light in meters per second and f is the frequency of the oscillator.

Method and apparatus for calculating carbon content of fly ash


An electronically controlled camera comprises a zoom lens which is capable of being driven to move in the direction of the optical axis thereof within a zooming area between a tele extremity and a wide extremity. A single operation member is provided for instructing the movement direction of the zoom lens, and the zoom lens is driven to move either stepwisely or continuously in accordance with the operating amount of the operation member.

The present invention relates to an electronically controlled camera using a zoom lens.
Conventionally, in a camera provided with a zoom lens, an operating member such as a zoom lever has been used for moving the zoom lens within a zoom range in order to arbitrarily set the focal length of the lens.
In such a camera, it is difficult to accurately locate the zoom lens at the position corresponding to a desired focal length in order to obtain a desired frame composition. When the distance between the current lens position and the position corresponding to the desired focal length is relatively large, it is preferred that the zoom lens is moved fast. On the other hand, in order to adjust the lens position, the lens is preferred to be moved slowly.
In order to solve the above problem, a camera in which the moving speed of the zoom lens can be changed has been suggested. The most preferable method is that the speed of the lens movement can be controlled in response to the operating amount of the operating member. If constructed in this way, however software as well as an electric circuit therefore becomes complicated.
Alternatively, it is suggested is the method that the zoom lens be moved stepwisely. In this case, the zoom lens is shifted to one of predetermined lens stop positions, and thereby the lens is accurately located at the position corresponding to the desired focal length.


A process for providing an improved hermetically sealed capacitor which includes the steps of applying a solder and a flux to an interior surface of a case; flowing the solder onto the interior surface; remove flux thereby forming a flux depleted solder; inserting the capacitive element into the casing; reflowing the flux depleted solder thereby forming a solder joint between the case and the solderable layer; and sealing the case.

The present invention is related to an improved hermetically sealed polymer capacitor and method of making an improved hermetically sealed polymer capacitor.
Hermetically sealed capacitors comprising polymeric cathodes have been utilized in the art for some time. One systemic problem with hermetically sealed capacitors comprising polymeric cathodes is a gradual increase in equivalent series resistance (ESR) and direct current leakage (DCL) at elevated temperatures. These systemic problems have always been considered a function of cathode breakdown and have therefore been accepted as an inherent function of the capacitor type.
Through diligent research the present inventors have discovered a mechanism of degradation which was previously unrealized and not predicted. By eliminating the unexpected mechanism of degradation hermetically sealed capacitors comprising polymeric cathodes can be manufactured with significant improvement in ESR and DCL thereby providing capacitors with a thermal stability previously considered unavailable.
The present invention provides a method of manufacturing a hermetically sealed capacitor comprising a polymeric cathode wherein the capacitor has improved thermal stability as indicated by improved ESR and DCL after exposure to elevated temperatures.

Hermetically sealed polymer capacitors with high stability at elevated temperatures


A multi-domain ESD protection circuit structure is described. The preferred embodiment of the present invention selects power lines of an internal circuit as ESD buses. The power lines of the remaining internal circuits are coupled with the ESD buses through the ESD connection cells. In another embodiment of the preferred invention, the VDD power line from one internal circuit and the VSS power line from another circuit are selected as ESD buses. In yet another embodiment, either a VDD power line or a VSS power line of an internal circuit is selected as an ESD bus.

It is well known that extremely high voltages can develop in the vicinity of an integrated circuit due to the build-up of static charge. A high potential may be generated to an input or output buffer of an integrated circuit, which may occur by a person simply touching a package pin, which is in electrical contact with an input or output buffer of the integrated circuit. When the electrostatic is discharged, a high current is produced at the package nodes of the integrated circuit. ElectroStatic Discharge (ESD) is a serious problem for semiconductor devices since it has the potential to destroy the entire integrated circuit.
The duration of the ESD transient is very short, typically in the order of nanoseconds, so that the conventional circuit breakers do not react quickly enough to provide adequate protection. For this reason, it is rapidly becoming a known practice to incorporate an ESD protection system in the circuitry itself. Conventionally, bi-directional diode strings are coupled between the nodes to protect the circuit. Other ESD devices such as transistors are also being used. ESD devices are also widely used between power lines to protect the internal circuit coupled between power lines and to discharge the ESD current to the ground.
For the purpose of decoupling noise, power lines in the integrated circuit are separated so that the noise generated in one part of the circuit does not affect another part of the circuit. However, the separation of the power lines creates more power lines that are subject to ESD. Therefore, more power line ESD protection schemes were developed.
FIG. 1 illustrates a conventional power domain ESD protection circuit. VDD power line 2 and VSS power line 6 form one power domain and VDD power line 4 and VSS power line 8 form another power domain. Internal circuit 10 is coupled between power lines 2 and 6 and internal circuit 12 is coupled between power lines 4 and 8. Bi-directional diode string 24 is used to protect circuit 10, and bi-directional diode string 30 is used to protect circuit 12. Since ESD may occur between power lines of different power domains, such as power lines 2 and 4, 6 and 8, ESD protection circuits are also required between power domains. As shown in FIG. 1, bi-directional diode string 14 is coupled between power lines 2 and 4, and a bi-directional diode string 18 is coupled between power lines 6 and 8. If a voltage transient occurs between power lines 2 and 4, the diode string 14 conducts in one direction and provides a path for electrostatic charges. Similarly, the diode string 18 between power lines 6 and 8 helps to eliminate the voltage transient between these two power lines.
When more power domains are used in the integrated circuit, every two adjacent power lines should be protected by an ESD protection circuit, therefore, the number of protection circuits increases dramatically. A more effective protection scheme, which was taken from U.S. Pat. No. 6,144,542, is devised by using ESD buses, as shown in FIG. 2. ESD buses 102, 108 and 112 formed of highly conductive materials are added into the circuit. Each VDD power line is connected to an ESD bus through an ESD connection cell wherein the ESD connection cells 11, 21, 31, . . . k1 are normally bi-directional diode strings or devices made of silicon-controlled rectifiers (SCR). VSS power lines are connected to an ESD bus 102 through ESD connection cells 12, 22, 32, . . . k2. The ESD buses are coupled with ESD clamp devices 100, 104 and 106, wherein the ESD clamp devices can be made of bi-directional diode strings or SCRs.
Comparing to the prior art in FIG. 1, instead of being coupled to each adjacent power line through an ESD protection device, a power line only connects to one ESD bus through an ESD connection cell. This greatly reduces the number of ESD protection devices required. In an example with a typical scenario, a transient occurs at one node in internal circuit i and a grounded node is at a node in another internal circuit j, where i and j are circuit numbers. The ESD current needs to go through at most two ESD connection cells, one connecting circuit i and the ESD bus and one connecting circuit j and the ESD bus. The ESD current also goes through at most one ESD clamp device in order to be conducted from one ESD bus to another.

Multi-domain ESD protection circuit structure

Taiwan Semiconductor Manufacturing Company, Ltd.


Methods and apparatus are disclosed for delivering enhanced caller information to a called party. A user document associated with a calling party is provided to the called party as part of signaling information associated with the call, such as a SIP invite message. The user document may be, for example, a vCard or vCalendar.

Modern telephone systems generally provide a caller identification feature for identifying the calling party. Caller ID services have become very popular with both residential and business customers. Caller ID services are especially valuable to businesses that use caller ID information to access customer records associated with an incoming call or to route an incoming call to specific customer representatives based on characteristics of the caller, such as a geographic location of the caller. In addition, residential customers frequently employ the caller ID feature to screen unwanted incoming calls.
Generally, customers register for a caller ID service with their telephone service provider. Typically, the customer is connected to the facilities of a service provider through a central office switch. If a called party subscribes to the caller ID service, information about the caller is automatically displayed on a display associated with the telephone of the called party whenever a call is received.
The information displayed about the caller is typically limited to the caller's name or telephone number (or both). U.S. Pat. No. 5,771,283 to Chang et al., entitled "Method for Delivering Enhanced Caller Identification Service in a Telecommunications Network," discloses a method for delivering enhanced caller identification services to a subscriber. Chang et al. extend the conventional caller ID feature to include information about the geographic location of the caller. Generally, if a called party subscribes to the enhanced caller ID service proposed by Chang et al., the directory number of the calling party is supplemented with geographic identification data associated with the originating switch, so that the true geographic location of the caller can be ascertained.
U.S. patent application Ser. No. 10/261,242, entitled "Method and Apparatus for Delivering Enhanced Caller Identification Services to a Called Party," discloses a caller ID system that provides a user document address to a called party. The user document address is a pointer or hyperlink, such as a uniform resource locator (URL), to a user document containing additional information about the calling party. While the disclosed caller ID system extends the caller ID information that is presented to a called party, the called party must use the address to access the identified document. For example, in a URL implementation, the called party must have an active Internet connection to obtain the document identified by the URL.
A need therefore exists for an improved method and apparatus for delivering enhanced caller identification services to a called party.

Method and apparatus for delivering enhanced caller identification services to a called party


A semiconductor structure includes a semiconductor substrate, a metal layer, an interlayer dielectric (ILD) layer. The metal layer is disposed over the semiconductor substrate. The ILD layer is over the semiconductor substrate and laterally surrounding the metal layer, in which the ILD layer has a first portion in contact with a first sidewall of the metal layer and a second portion in contact with a second sidewall of the metal layer opposite to the first sidewall of the metal layer, and a width of the first portion of the ILD layer decreases as a distance from the semiconductor substrate increases.

The semiconductor integrated circuit (IC) industry has experienced rapid growth. Technological advances in IC materials and design have produced generations of ICs where each generation has smaller and more complex circuits than the previous generation. However, these advances have increased the complexity of processing and manufacturing ICs and, for these advances to be realized, similar developments in IC processing and manufacturing are needed.
A metal-filling operation is a common and widely used operation to form a semiconductor device. However, with decreasing in a dimension of a semiconductor structure and increasing in an aspect ratio of the semiconductor structure, challenges in the metal-filling operation become more and more significant. A solution tackles the encountered problems is required.

Method of forming semiconductor structure having layer with re-entrant profile

TAIWAN SEMICONDUCTOR MANUFACTURING CO., LTD.


A method is for calibration of perfusion parameter images. The image data from tomographic imaging measurements are analyzed using a perfusion model, and perfusion parameter values obtained from the analysis are calibrated with a calibration factor to a physiological normal value. To perform the calibration, an image area which contains several different tissue compositions, and in which approximately normal perfusion conditions can be assumed, is selected from the obtained perfusion parameter image. A frequency analysis of the perfusion parameter values contained in this image area is then performed, and at least one frequency interval is selected which corresponds at least approximately to a frequency interval of the occurrence of perfusion parameter values of a known tissue composition. A mean value is calculated from the perfusion parameter values in the frequency interval, and a comparison with the physiological normal value for this tissue composition is made in order to determine the calibration factor or a calibration value included in the calibration factor. The method permits automatic or substantially automatic calibration of perfusion parameter images.

Image-producing perfusion measurements of organs represent an important tool in medical diagnosis. This applies particularly to the measurement of cerebral perfusion parameters which are used to present acute cerebral perfusion disorders, for example in the diagnosis of ischemic cerebral infarct. When measuring perfusion parameters, for example cerebral blood flow (CBF) or cerebral blood volume (CBV), several tomographic images of the same examination volume, generally sectional images of a predetermined layer of the brain, are taken in chronological succession following injection of a contrast medium bolus and are analyzed to determine the perfusion parameters.
Most imaging methods for determining brain perfusion parameters use tracer-kinetic models with which the perfusion parameters from the image data of the image are calculated in order then to present the perfusion parameters in image form. These perfusion parameter images then make it possible, for example, to assess the degree of severity and extent of ischemia.
Examples of models used, and the determination of various perfusion parameters in cerebral perfusion computed tomography, are set out in the publications by M. König et al., "CT-Perfusionsbildgebung beim akuten ischämischen Hirninfarkt: Vergleich von Parameter-bildern der zerebralen Perfusion und Nativ-CT-Befunden", [CT perfusion imaging in acute ischemic cerebral infarct: Comparison of parameter images of cerebral perfusion and native CT findings], Fortschr Röntgenstr 2000, 172, pages 219-226, and M. König et al., "Zerebrale Perfusions-CT: Theoretische Grundlagen, methodische Realisierung und praktische Erfahrungen in der Diagnostik des ischämischen Hirninfarktes" [Cerebral perfusion CT: Theoretical principles, methodology and practical experience in diagnosis of ischemic cerebral infarct], Fortschr Röntengstr 2000, 172, pages 210-218. The perfusion computed tomography used here has the advantage, compared to other imaging methods, that changes in concentration of the contrast medium in the vessel system are reflected directly in a proportional change of the CT values.
Nowadays, in addition to simple sectional images of the brain, it is possible, using multisection computed tomography, to measure larger volume areas of the brain or of other organs by simultaneous recording of several parallel sections.
The need to use models to determine the perfusion parameters from the image data often leads to methodology problems, since either it is not possible to produce an optimal injection bolus, or one of the parameters needed for the determination cannot be recorded with sufficient absolute accuracy. Although the perfusion parameter images obtained do then correctly reflect the relative perfusion conditions within the measured examination volume, they are associated with a patient-dependent, systematic error, which makes determination of the absolute values difficult. This is not an actual limitation for clinical diagnosis, because the image impression in most cases already permits adequate diagnosis, and relative values permit a quantitative analysis (cf. M. König et al.; "Quantitative Assessment of the Ischemic Brain by Means of Perfusion-Related Parameters Derived from Perfusion CT"; Stroke 2001; 32: 431-437).-However, a calibration to physiological normal values is desirable because, among other things, it permits normalized color image presentation, which greatly increases acceptance by users, for example neurologists.
In a known technique for calibration of perfusion parameter images, an ROI (region of interest) is placed manually in an anatomically coherent region of known tissue composition, and the perfusion parameter value in this ROI is determined. From the relationship of this value and an assumed physiological normal value for this tissue composition it is possible to determine, for the entire image, a calibration factor with which all perfusion parameter values of the image are scaled.
However, this procedure has some disadvantages. Thus, the ROI has to be positioned manually and its size must be adapted in order to obtain an image area of homogeneous composition. Because of the substantial layer thicknesses which are needed for adequate contrast in image-producing perfusion measurements, there are only a few areas of really homogeneous tissue composition. This applies above all to the gray matter of the brain, in respect of which corresponding ROIs must be chosen very small. Although larger cerebral medulla areas can be selected, these have lower perfusion parameter values, with the result that they produce more noise. In elderly patients, the values in these areas are also much more variable.

Method for automatic calibration of perfusion parameter images


Elevator tension members are disclosed. The disclosed tension member longitudinally extends along a longitudinal axis and includes a plurality of fibers formed into one or more primary strands or cords extending parallel to the longitudinal axis and a plurality of fibers formed into one or more secondary strands or cords extending parallel to the longitudinal axis and through less than the full length of the belt, and a jacket retaining the primary and secondary strands or cords. The secondary strands or cords have a tensile modulus greater than a tensile modulus of the jacket and less than a tensile modulus of the primary strands or cords. Methods of making the tension member are also disclosed.

Technical Field
The present disclosure is directed to tension members such as those used in elevator systems for suspension and/or driving of the elevator car and/or counterweight.
Description of the Related Art
Traction elevators are widely used. In general, a traction elevator system can include a car, a counterweight, one or more tension members interconnecting the car and counterweight, a traction sheave to move the tension member, and a motor-driven machine to rotate the traction sheave. The sheave is formed from cast iron.
In some elevators, the tension member is a rope formed from twisted steel wires. In other elevators, the tension member is a belt with the twisted wires retained in a polymer jacket. In any event, the transfer of the propulsive load between the sheave and the tension member requires coupling of shear forces along the contact length between the sheave and the tension member. With a belt as the tension member, if the shearing force exceeds the total pullout strength along the contact length, the jacket may crack, deform, or even separate from the belt.
In general, a conventional elevator tension member can include a plurality of steel wires of specific number, size and geometry for purposes of strength, cost of production, and/or durability. The polymer jacket used to retain the steel wires is usually made of polyurethane or other suitable polymer materials. However, as the tensile strength of steel is significantly higher than that of polyurethane, the polymer jacket may be susceptible to premature wear under the aforementioned shear forces, especially along the contact length between the steel wire and the iron sheave.
One way to address this issue is to reinforce the jacket with secondary tension members. For example, one elevator belt is known as including a plurality of planar steel cords encased in a polyurethane jacket, which is reinforced with a plurality of polymer cords distributed throughout the entire jacket. Moreover, each polymer cord is extending through the entire length of the belt. While effective in providing reinforcement to the elevator belt, the polymer cords may increase bending stiffness and may cause localized stress concentration, either of which may adversely affect the performance or service life of the elevator belt. Moreover, the polymer cords distributed throughout the entire jacket may increase the production cost and production time of the elevator belt.
Some power transmission belts, such as timing belts or serpentine belts in automobiles, includes interwoven reinforcement fibers encased in a polymer jacket. Such designs are labor intensive and consume more material, but are necessary for the strength of the belt due to the lack of stronger primary tension members (e.g. steel wires) in the power transmission belts.


A magnet valve is installed by a method in which the fully machined valve member is locked in a receptacle of a fixed installation device. A magnet plate and a spacer plate are mounted on a receiving mandrel. The magnet plate, spacer plate and valve member are pressed against the receptacle, then the magnet plate and the spacer plate are displaced relative to the valve member, and the armature is secured to the receiving mandrel of the valve member in such a way that the armature then rests on the magnet plate.

1. Field of the Invention
The invention relates to a unit fuel injector (UFI) and to a pump-line-nozzle unit (PLNU) for an internal combustion engine, with a pump element, the pump element having a pump chamber, and with a magnet valve, the magnet valve having a valve member and an armature; the magnet valve opens or closes a hydraulic connection between the pump chamber and a low-pressure region of the unit fuel injector.
2. Description of the Prior Art
In connection with the invention, the following discussion will refer only to the unit fuel injector (UFI), although pump-line-nozzle units (PLNUs) are always intended as well. The most essential distinction between unit fuel injectors and pump-line-nozzle units is that a pump-line-nozzle unit has a short high-pressure line between the pump element and the injection nozzle. For the present invention, this distinction does not matter, and hence the invention applies equally for unit fuel injectors and pump-line-nozzle units.
A unit fuel injector is known for instance from German Patent Disclosure DE 198 37 333 A1. In this unit fuel injector, the valve and the armature of the magnet valve are connected to one another nonpositively by a compression spring. Because the valve member and the armature are coupled only nonpositively, the dynamic performance of the magnet valve is difficult to control, and it is hardly avoidable that during operation, the armature and the valve member will repeatedly briefly separate from one another and after that collide again. This process is known as "bouncing". The bouncing is unwanted, since it has an adverse effect on the precision with which the magnet valve opens and closes. Moreover, the bouncing causes high wear to the armature, which is of a soft material, so that the valve stroke and thus also the operating performance of the magnet valve vary over the course of time. Finally, it should also be mentioned that the armature must be guided in a capsule, and for structural reasons this guide can only be relatively short. As a consequence, the armature has a tendency to tilting, and the armature guide wears down relatively quickly.
In a unit fuel injector and a pump-line-nozzle unit according to the invention for an internal combustion engine, with a pump element, the pump element having a pump chamber, and with a magnet valve, the magnet valve having a valve member and an armature, and in which the magnet valve opens or closes a hydraulic connection between the pump chamber and a low-pressure region, it is provided that the armature is fixedly connected to the valve member.


In a video processing system (14), a method of detecting and compensating for motion of an image which includes the steps of: detecting a first pixel value, a second pixel value, and a third pixel value, the first pixel value of a first scan line in a first field, the second pixel value of a second scan line in the first field, and the third pixel value in a second field; providing a motion indicator based on the first, second, and third pixel values; selecting a plurality of interpolation coefficients from a memory based on the motion indicator signal; and providing an interpolated color space pixel based on a first color space pixel associated with the first pixel value, a second color space pixel associated with the second pixel value, and based on the plurality of interpolation coefficients.

In video processing systems, such as systems that enhance a standard NTSC television signal to produce a higher resolution signal for display on a television display, a common problem is accounting for motion in an image to be displayed. To address this problem, many different circuits have been proposed to detect and to compensate for the motion of the image. However, such circuits typically include many electronic components, resulting in relatively low efficiency, high power, and high hardware costs.
Accordingly, there is a need for an improved method and system for detecting motion of an image in a video processing system. It would be particularly desirable if such improved method and system provided higher efficiency, lower power, and lower costs than conventional video processing methods and systems.

Methods and systems for processing video signal pixel data


An ion implantation system employs a mass analyzer for both mass analysis and angle correction. An ion source generates an ion beam along a beam path. A mass analyzer is located downstream of the ion source that performs mass analysis and angle correction on the ion beam. A resolving aperture within an aperture assembly is located downstream of the mass analyzer component and along the beam path. The resolving aperture has a size and shape according to a selected mass resolution and a beam envelope of the ion beam. An angle measurement system is located downstream of the resolving aperture and obtains an angle of incidence value of the ion beam. A control system derives a magnetic field adjustment for the mass analyzer according to the angle of incidence value of the ion beam from the angle measurement system.

In the manufacture of semiconductor devices, ion implantation is used to dope semiconductors with impurities or dopants. Ion beam implanters are used to treat silicon wafers with an ion beam, in order to produce n or p type extrinsic material doping or to form passivation layers during fabrication of an integrated circuit. When used for doping semiconductors, the ion beam implanter injects a selected extrinsic ion species to produce the desired semiconducting material. Implanting ions generated from source materials such as antimony, arsenic or phosphorus results in "n type" extrinsic material wafers, whereas if "p type" extrinsic material wafers are desired, ions generated with source materials such as boron, or indium may be implanted.
Typical ion beam implanters include an ion source for generating positively charged ions from ionizable source materials. The generated ions are formed into a beam and directed along a predetermined beam path to an implantation station. The ion beam implanter may include beam forming and shaping structures extending between the ion source and the implantation station. The beam forming and shaping structures maintain the ion beam and bound an elongated interior cavity or passageway through which the beam passes en route to the implantation station. When operating an implanter, this passageway can be evacuated to reduce the probability of ions being deflected from the predetermined beam path as a result of collisions with gas molecules.
Trajectories of charged particles of given kinetic energy in a magnetic field will differ for different masses (or charge-to-mass ratios) of these particles. Therefore, the part of an extracted ion beam which reaches a desired area of a semiconductor wafer or other target after passing through a constant magnetic field can be made pure since ions of undesirable molecular weight will be deflected to positions away from the beam and implantation of other than desired materials can be avoided. The process of selectively separating ions of desired and undesired charge-to-mass ratios is known as mass analysis. Mass analyzers typically employ a mass analysis magnet creating a dipole magnetic field to deflect various ions in an ion beam via magnetic deflection in an arcuate passageway which will effectively separate ions of different charge-to-mass ratios.
For some ion implantation systems, the physical size of the beam is smaller than a target workpiece, so the beam is scanned in one or more directions in order to adequately cover a surface of the target workpiece. Generally, an electrostatic or magnetic based scanner scans the ion beam in a fast direction and a mechanical device moves the target workpiece in a slow scan direction in order to provide sufficient cover.
Thereafter the ion beam is directed toward a target end station, which holds a target workpiece. Ions within the ion beam implant into the target workpiece, which is ion implantation. One important characteristic of ion implantation is that there exists a uniform angular distribution of ion flux across the surface of the target workpiece, such as a semiconductor wafer. The angular content of the ion beam defines implant properties through crystal channeling effects or shadowing effects under vertical structures, such as photoresist masks or CMOS transistor gates. A non-uniform angular distribution or angular content of the ion beam can lead to uncontrolled and/or undesired implant properties.
Beam diagnostic equipment can be employed to measure the angle content of ion beams. The measurement data can then be employed to adjust angle characteristics of the ion beam. However, conventional approaches can increase complexity of the ion implantation system and undesirably increase the length of path along which the ion beam travels.

Systems and methods for beam angle adjustment in ion implanters


A recombinant nucleic acid containing a transcriptional enhancer from a rice αAmy8 gene, a promoter operably linked to the enhancer, and a coding sequence operably linked to the promoter and encoding a transcript. Also disclosed is a stably transformed plant cell or a transgenic plant containing a recombinant nucleic acid described above, or a similar recombinant nucleic acid with a plurality of a rice αAmy3 enhancer.

Various strategies have been employed to increase the activity of promoters in transgenic plants. One of the strategies is to use an enhancer that increases the transcriptional activity of a promoter, either homologous or heterologous to the enhancer. This strategy is useful in producing transgenic plants over-expressing endogenous or exogenous genes that control agronomically important traits or over-production of biomolecules.

Rice α-amylase transcriptional enhancers