A full color, pulsed laser video system having solid state red (R), green (G) and blue (B) lasers (10, 12, 14) as a source, and with a projection screen having a two-channel image (24) for the screen, and with optical fiber remote image delivery (30).

A pulsed laser video imaging system and method is set forth in U.S. Pat. Nos. 4,720,747 and 4,851,918, issued on Jan. 19, 1988, and Jul. 25, 1989, respectively, both hereby incorporated by reference. These patents describe a video imaging system responsive to input signals representing a video image and employ one or more pulsed lasers, such as metal vapor lasers, to provide one or more monochromatic light sources.
The invention relates to a laser video display system and method. In particular, the invention relates to a full color, laser video image system wherein the pulsed laser light source comprises a green (G) laser with controlled multimode operation to minimize speckle, a tunable blue (B) laser and a red (R) laser with sum of frequency mix.
It is desirable to provide a new and improved pulsed laser projection system and method with one or more of the following improvements. The list of improvements include:
1. all solid state green laser design with controlled multimode operation to minimize speckle;
2. all solid state tunable blue laser design;
3. all solid state red laser design with sum of frequency mix;
4. diode laser pumped, all solid state, monochromatic red, green and blue light source with color space conversion;
5. uniform intensity line generation by a cylindrical asphere lens set;
6. two channel image output with achromatic image inversion;
7. remote image delivery by coherent fiber ribbon;
8. horizontal video line time adjustment (compression and expansion);
9. nonlinear control of vertical scanner (i.e., tangential correction); and
10. horizontal pixel time correction with sub-clock timing.
The various components of the improved laser video image system and method, and the differences and improvements from prior art systems and methods are set forth in detail below.
(1) All Solid State Green Laser Design with Controlled Multimode Operation to Minimize Speckle
The original invention described in U.S. Pat. No. 4,720,747 specifies the use of metal vapor lasers as light sources. U.S. Pat. No. 3,818,129, issued Jun. 18, 1974, to Yamamoto, incorporates use of a cw lamp pumped, repetitively Q-switched, frequency doubled Neodymium:Yttrium Alminum Garnet (Nd:YAG) laser (wavelength=532 nm) to be a light source for green, and it cites the short pulse duration and high average power as the primary reasons for the choice of the above-mentioned laser. However, U.S. Pat. No. 3,818,129 fails to mention another important factor affecting image quality, which is output beam quality from the above-mentioned laser.
Generally speaking, the output beam quality from the cw lamp pumped, repetitively Q-switched, frequency doubled, Nd:YAG laser with high output power tends to have a high multimode structure in transverse direction, which results in high beam divergence; therefore producing undesirable image blur at a screen. The above-mentioned laser can be constructed to produce near diffraction limited, single mode output (TEMoo mode) which minimizes the beam divergence; however, TEMoo mode output does maximize laser speckle effect, which is not desirable.
Then what is needed is the cw lamp pumped, repetitively Q-switched, frequency doubled Nd:YAG laser cavity design which produces controlled multimode output in transverse direction that minimizes the laser speckle and still produces reasonably crisp images on the screen surface because of optically manageable beam divergence. M2 is a measurable quantity which characterizes output beam spot size at far field and its divergence. When M2 is equal to one, the output beam is called diffraction limited beam or TEMoo mode, whereas when M2 is large (i.e., xcx9c100), then the output beam is said to have a high multimode structure. The acceptable range of M2 for the laser video display discussed in this invention is semi-empirically determined to be between 10 and 20. To achieve the acceptable range of M2=10-20, the cw lamp pumped, repetitively Q-switched, frequency doubled Nd:YAG laser has an intra-cavity aperture to strip excess modes, and the frequency doubling process is achieved by a Type II LBO (lithium triborate) or KTP (potassium titanyl phosphate) placed within the laser cavity. The schematic drawing of this green laser cavity is shown in FIG. 3.
(2) All Solid State Tunable Blue Laser
Blue light is produced by a frequency doubled Ti:Sapphire (Ti:Al2O3) laser, which is longitudinally pumped by the cw lamp pumped, repetitively Q-switched, frequency doubled Nd:YAG laser (wavelength=532 nm). The Ti:Al2O3 laser has broad range of near infrared emission; thus, it can be tuned to a specific wavelength by a set of birefringent plates, and for this particular application, the IR emission is tuned at 900 nm. The frequency doubling process is achieved by placing a Type I LBO or BBO (beta-barium borate) within the Ti:Al2O3 laser cavity (i.e., intra-cavity frequency doubling), which results in emission of blue light at 450 nm. Finally, the range of blue emission from this frequency doubled Ti:Al2O3 laser can be tunable by adjusting the angle of the birefringent plates. The schematic drawing of the frequency doubled Ti:Al2O3 laser is shown in FIG. 4.
(3) All Solid State Red Laser with Sum of Frequency Mix
A cw lamp pumped, repetitively Q-switched Nd:YAG laser produces primary laser radiation of 1064 nm. This 1064 nm radiation is used to pump the potassium titanyl arsenate (KTA) based intracavity optical parametric oscillation (OPO) and sum of frequency mix (SFM) mechanism to produce red light in wavelength between 626 nm and 629 nm. When KTA crystal is pumped by 1064 nm, it has been demonstrated to produce the signal (1520 nmxcx9c1540 nm) and the idler (xcx9c3540 nm) waves, and unlike KTP, the KTA does not exhibit reabsorption of the idler wavelength (xcx9c3540 nm); thus, relatively high conversion efficiency is expected from KTA based OPO once the pump beam exceeds OPO threshold. A separate Type III KTP will be used to achieve the sum of frequency mix process, and it has a phase match angle of 77xc2x0 for SFM process between the wavelength of 1520 nmxcx9c1540 nm and 1064 nm, producing the resultant red wavelength of between 626 nm and 629 nm. Similarly, Type II KTA or Type I LBO can be used to achieve sum of frequency mix (SFM) between 1520xcx9c1540 nm and 1064 nm to produce the desired red wavelength of 626xcx9c629 nm, instead of Type III KTP discussed above.
The lasing mechanism to generate 1064 nm radiation, and KTA based OPO, and subsequent KTP based SFM process can be placed in the same cavity structure (intra-cavity design) or the two can be separated, depending on peak power of 1064 nm radiation. The schematic drawing of the former cavity design is shown in FIG. 5.
(4) Diode Laser Pumped, All Solid State, Monochromatic Red, Green and Blue Light Source with Color Space Conversion
The all solid state red, green and blue laser designs discussed previously are based on cw lamp pump mechanism to produce primary laser radiation of 1064 nm from Nd:YAG crystal. However, diode laser pumped, all solid state red, green and blue laser light source described in U.S. Provisional Patent Application No. 60/032,269, filed Nov. 29, 1996 (Title: xe2x80x9cMonochromatic R,G,B Laser Light Source and Display Systems by Masayuki Karakawa), will also be used as an alternative light source to produce three primary colors. This diode laser pumped, all solid state red (wavelength: 626xcx9c629 nm), green (wavelength: 532 or 523.5 nm) and blue (wavelength: 450 or 447 nm) laser light source also incorporates digital color space conversion electronics circuit and produces a very short pulse at a high repetition rate.
(5) Uniform Intensity Line Generation by a Cylindrical Asphere Lens Set
In the laser video projection system described in U.S. Pat. Nos. 4,720,747 and 4,851,918, each pulse of laser light having Gaussian intensity distribution, from one or more laser source must be converted to a line by an optical set up, and enters into an acousto-optic cell which acts as a spatial light modulator. In this process it is important to have the optical set up, which converts the laser beam having circular cross section and Gaussian intensity distribution into a well-collimated, uniform intensity, thin line, in order to have good image quality at the screen and achieve maximum coupling with the acousto-optic cells.
In U.S. Pat. Nos. 4,720,747 and 4,851,918, the optical set up, which consists of a pair of cross-cylinder lenses with a collimator is suggested, and in U.S. Pat. No. 3,818,129, no particular optical set up is mentioned in this area. A pair of cross-cylinder lenses with a collimator approach does produce a line; however, the intensity distribution and the line thickness are not uniform across the line.
The improved optical set up disclosed herein consists of a cylindrical asphere lens and a pair of cylinder lenses cemented together to form a collimator set. The primary function of the cylindrical asphere lens is to convert a laser beam with circular cross section and Gaussian intensity distribution into a uniform intensity thin line, and the collimator set, made of a pair of cylinder lenses cemented back to back, keeps the line stray collimated at far field. An aspherical surface of the cylindrical asphere lens is given by equation:
X=cy2/[1+(1xe2x88x92c2y2(1+k))xc2xd]+A4y4+A6y6+A8y8+A10y10+ - - -
where k is conic constant and c is curvature.
It is very important to note that inclusion of the higher order terms (i.e., A4y4, A6y6, A8y8, A10y10, - - -) are essential to produce uniform intensity distribution across the entire line; thus, they should not be overlooked. The higher order coefficients such as A4, A6, A8, A10, - - - are determined based on the precise spatial intensity distribution (a measurable quantity) of the source laser beam.
(6) Two Channel Image Output with Achromatic Image Inversion
For a certain application, it is desirable to project two identical images on two different screen surfaces by one projector. To achieve this effect, it is necessary to:
1. split the image in half by trichroic beam splitter, which transmits 50% of the image through and also reflects the remaining 50% of the image;
2. apply necessary achromatic corrections to the reflected image to compensate color differences among red, green and blue, since the coating on the trichroic beam splitter may not divide red, green and blue images exactly in half;
3. then invert the reflected image, so that its geometry is the same as the transmitted one; and
4. finally, two images, the transmitted and reflected ones, are vertically scanned by two galvanometer driven scanners, controlled by the single electronic circuit, so that the two images are always at sync.
The schematic drawing of optical set up to achieve two image output, with achromatic image inversion, as described above is shown in FIG. 6.
(7) Remote Image Delivery by Coherent Fiber Ribbon
For a certain applications, it is desirable to decouple a main portion of the laser video projector mechanism, which includes red, green and blue lasers, three acousto-optic cells, and other optical components up to zero order focus (ZOF) beam block and a projector head, which includes the galvanometer driven vertical scanner and projection optics, and then connect them with fiber cable.
Since prior to launching into fiber all the imaging functions, including line-thickness control, and R,G,B field matching have been performed, the fiber cable used here should be 1xc3x97N coherent fiber ribbon, where N should be a sufficiently large number (integer) and preferably close to the number of horizontal pixels. The coherent fiber ribbon set up is necessary to preserve already encoded video images from one end of the fiber to the other end.
Two different applications are envisioned for this remote image delivery method by 1xc3x97N coherent fiber ribbon. The first application is single projector/single display use, and the second application is single projector/multiple display use. The only difference between the two applications is that in the second application, the image is divided in half by a fused fiber image divider prior to launching into two separate 1xc3x97N coherent fiber ribbons, which are then connected to two separate projector heads.
The single projector/single display application is shown in FIG. 7 and the single projector/multiple display application is shown in FIG. 8.
(8) Horizontal Video Line Time Adjustment (Compression and Expansion)
In U.S. Pat. Nos. 4,720,747 and 4,851,918, electronic video line time compression (or data compression) concept is included. This allows the use of a smaller size aperture, acousto-optic cell; thus, enabling the input laser light to attain high diffraction efficiency into the first order when the input signal considered is NTSC video signal only.
However, there are many other video signal formats available now, and for certain input signals applications, it is desirable and necessary to expand the input video line time. For example, consider the input signal having the resolution of 1280 (H) pixels by 1024 (V) lines at 72 Hz refresh rate with progressive scan format (non-interlace format): The horizontal video line time for this input signal is approximately equal to 11-12 xcexcs; whereas, the necessary aperture time for the acousto-optic cell is approximately equal to 22 xcexcs, if the multi-line writing scheme is implemented. Furthermore, for an anisotropic, acousto-optic cell, such as TeO2 operating in sheer mode, there is not much difference in diffraction efficiencies into the first order between 11 xcexcs (horizontal lengthxcx9c6.8 mm) aperture and 22 xcexcs (horizontal lengthxcx9c13.6 mm). Therefore, what is needed is not just video line time compression, but video line time adjustment, which includes compression and expansion means to manipulate input video line time best suited for different applications.
The input video line time expansion can be achieved in a similar manner as video line time compression by:
1. storing input each horizontal video line data into line or frame buffers momentarily;
2. retrieving the stored data from the line or frame buffers with different rates from the input video signal;
3. sending the output video signal to one or more transducers attached to acousto-optic cells; and
4. when the output video signal rate is shorter than the input one, the signal is compressed; whereas, if the output video signal rate is longer than the input one, the signal is expanded in time domain.
(9) Nonlinear Control of Vertical Scanner
Generally speaking, a galvanometer based vertical scanner, driven by linear ramp signal, makes incremental vertical sweep, with equally spaced angular displacement for given oscillation rate, and its linearity (i.e., each angular displacement) is known to be excellent.
However, when the galvanometer based vertical scanner is used to project each horizontal video line onto the screen surface with relatively short throw distance, the equally spaced angular displacement motion of the vertical scanner, driven by a series of linear ramp signals, does not translate into equal spatial spacing of each horizontal line at the screen surface. The actual result is that the horizontal line spacing is closer together at the top and bottom of the screen, and they are more apart at the center of the screen. In order to achieve equal spatial spacing of each horizontal line at the screen surface, the galvanometer driven vertical scanner has to be driven by nonlinear ramp signals, providing unequally spaced angular displacement motion.
Refer to FIG. 9, which shows each angular displacement of the vertical scanner and the screen surface, the ith incremental angular displacement made by the vertical scanner resulting in the projection of the ith horizontal line onto the screen is given by the equation:
Ai=ArcTan [Tan (Aixe2x88x921+Aixe2x88x922+Aixe2x88x923+ - - - +A2+A1)+Tan A1]xe2x88x92(Aixe2x88x921+Aixe2x88x922+Aixe2x88x923+ - - - +A2+A1)
Where:
A1=ArcTan (L/D)
L=Identical spacing for each horizontal line at the screen surface=H/N
H=Height of the screen
N=Total number of horizontal lines=vertical resolution of the image
D=Distance between the scanner and the center of the screen
The nonlinear angular displacement of the vertical scanner given by the equation above is used to calculate each angular displacement corresponding to each projected horizontal line, and the results can be programmed into look up tables within firmware, then the programmed data can be used to provide necessary electronics correction to ramp signal (tangential correction) which drives the vertical scanner.
(10) Horizontal Pixel Time Correction with Sub-clock Timing
When the laser video projector described in this invention is used with relatively short throw distance from the screen surface, the projected image suffers from a distortion known as xe2x80x9cpin cushionxe2x80x9d effect.
This distortion originates from the fact that it takes a longer time for a pixel to reach the upper or lower section of the screen than to reach the center section of the screen; therefore, the pixels at the top and bottom section of the screen expand more than those at the center section, resulting in the image having bow-shaped left and right edges.
In order to correct this image distortion, pixel by pixel-based time correction is needed such a manner, that additional time is assigned to a group of pixels corresponding to the center section of the image; whereas, lesser time is assigned to a group of pixels corresponding to the four upper and lower corners of the image. This pixel time correction is implemented within the acousto-optic cell in the following manner:
Consider a case with a video pixel time equal to 28 ns. Normally, this pixel signal is generated by 36 MHz master clock (f=1/28 nsxcx9c36 MHz) and pixel time interval does not change across the given video line within the acousto-optic cell. However, the additional sub-clock circuit oscillating at 500 MHz will provide +/xe2x88x922 ns change into the master clock circuit oscillating at 36 MHz, and the result enables the combined clock signal circuits to generate pixel time varying (28+/xe2x88x922.N)ns (where N is integer=0, 1, 2, . . . ). With this additional sub-clock circuit, the pixel time can be adjusted across the given video line so that shorter pixel time is assigned to a group of pixels at the both edges and longer time is assigned to a group of pixels at the center section of the video line.
This pixel time correction with sub-clock circuit produces the predistorted image within the acousto-optic cell, which will compensate for the xe2x80x9cpin cushionxe2x80x9d problem at the screen surface, resulting in an image with straight line left and right edges as desired.
The invention will be described for the purpose of illustration only in connection with certain illustrated embodiments; however, it is recognized that various changes, modifications, additions and improvements may be made in the illustrative embodiments without departing from the spirit and scope of the invention.


Sand control screens temporarily plugged with paraffin wax are installed in deep open hole wells wherein the wax has a melting temperature slightly greater or less than the nominal formation temperature in the zone from which well fluids are to be produced. Drilling fluids and other solids-laden wellbore fluids are removed from the wellbore by flowing the well up through a section of tubing disposed distal of the screen, through the interior of the screen and through the tubing string to the surface until the wellbore is cleaned. The wax is then melted due to the temperature of the produced fluid, is dissolved by the produced fluid or a solvent pumped down through the tubing string or is heated by a heater inserted into the interior of the screen such as a wireline conveyed electric heater. The distal tubing section is plugged so that production fluids are forced to flow through the sand control screen in a conventional manner.

1. Field of the Invention
The present invention pertains to a method of preferentially plugging a sand control screen for installation in a deep, open hole wellbore using a soluble or meltable screen plugging material which may be removed after clearing the wellbore of screen contaminating fluids, such as drilling mud.
2. Background
In the completion engineering of certain fluid producing wells, it is necessary or desirable to leave the wellbore in an "open hole" condition, that is, without installing and perforating a casing. Where possible, for example, generally horizontally extending wellbores are completed in an open hole condition due to the cost of installing and perforating casing over the substantial length of the fluid producing zone. In generally horizontal, open hole wells that require sand control equipment, so-called pre-packed sand control screens are usually installed at the end of the production tubing. The pre-packed screen not only prevents the production of formation sand into the produced fluid conducted through the tubing but also eliminates the need for a conventional gravel pack as a means of sand control.
However, one significant problem associated with completing an open hole well is the removal of drilling mud from the wellbore so that it does not contaminate and prematurely plug the sand control screen. Most drilling muds contain a weighting medium and a fluid loss control medium which are necessary during drilling but which can clog a sand control screen before substantial production of fluids from the well can begin. Although certain wellbore cleaning fluids can be circulated into the well into the vicinity of the producing zone to remove drilling mud prior to or during a sand control screen installation, these cleaning fluids can be expensive, particularly in deep, open hole wells wherein the formation fluid pressure is significant. The relatively high density brine type fluids preferred for cleaning deep wells may be prohibitively expensive. Accordingly, if the cost of the high density well cleaning fluids can be eliminated together with elimination of casing and perforation procedures in deep wells, the cost of these wells can be significantly reduced. Moreover, the procedures used in completing relatively shallow, horizontal type wells, even with relatively high velocity fluid circulation rates, are usually not effective in deep, generally vertical open hole wells where fluids such as drilling mud, having weighting agents to produce densities of 15 to 18 pounds per gallon, are required for well control.
Known methods to temporarily protectively plug a sand control screen usually require the use of an acid-soluble paste or wax that is painted over the exterior of the screen. Removal of this paste usually requires that acid or a solvent contact the entire exterior of the screen to effect paste or wax removal and this cannot be accomplished by forcing fluid down through the tubing string and out through the screen because the acid or solvent would flow through the small portion of the screen that is first opened and then would enter the formation. The remaining portions of the screen would never be cleaned except, perhaps, unless the acid or solvent was injected using coilable tubing. Coilable tubing operations in deep wells are particularly risky and it is desirable to avoid such operations where possible. If lower density cleaning fluids were to be used to circulate out the drilling fluid or "mud", the well would have to be "killed" after setting the production tubing packer which would then force drilling fluids solids through the inside of the screen and result in the likelihood of plugging the screen from that direction.
Certain developments have been carried out to place fluid impermeable coatings on sand control screens, which coatings can be removed at certain times in the screen installation. For example, U.S. patent application Ser. No. 07/774,393 filed Oct. 10, 1991 in the name of H. M. Cornette and assigned to the assignee of the present invention suggests placing a fluid impermeable paste on the inner surface of an auger type sand control screen to prevent the cross flow of fluid between different formation zones or intervals during screen installation and to prevent the flow of wellbore fluids into the gravel packing and out into the formation during screen installation when the well is in an overbalanced condition.
U.S. Pat. No. 2,224,630 to C. J. Dean, et al, and issued Dec. 10, 1940 describes the placement of a frangible liner on the inner screen surface and filling the screen perforations with a fusible material such as wax or asphalt during screen installation.
U.S. Pat. No. 3,880,233 to T. W. Muecke, et al and issued Apr. 29, 1975 describes provision of a sand control screen wherein a fusible material such as wax is applied to the inner and outer screen surfaces to prevent screen plugging during storage, handling and placement. However, Muecke, et al does not suggest the improvements of the present invention with respect to evacuating drilling fluid from the wellbore after the screen has been installed.
U.S. Pat. No. 4,202,411 to Sharp et al and issued May 13, 1980 describes the provision of a fluid impermeable inorganic matrix such as the reaction product of magnesium oxide and magnesium chloride as a well screen clogging preventative. However, as with the Muecke patent, Sharp et al does not suggest the arrangement or method of the present invention with respect to dealing with the evacuation of drilling fluid in deep open hole wells.
Smith U.S. Pat. No. 3,999,608 issued Dec. 28, 1976 and Schroeder, Jr., et al U.S. Pat. No. 5,062,484 and issued Nov. 19, 1991 deal with methods for gravel packing a well wherein the apertures in the gravel pack liner are sealed to prevent clogging during the installation of the gravel packing around the outside of the liner. Neither of these patents addresses or solves the problem associated with the present invention.
Certain other completion techniques normally used in shallow wells also have disadvantages. Accordingly, there has been a need to develop improved methods for installing sand control screens in deep open hole wells, in particular, to reduce the likelihood of prematurely plugging the screen with remnants of drilling fluid even before the production of formation fluids begins. The present invention solves this problem in a unique manner as will be appreciated by those skilled in the art upon reading the summary and detailed description of the invention which follows herein.

Sand control installation for deep open hole wells


In a process for chlorine-free bleaching of cellulose with an .alpha.-cellulose content of more than 90%, preferably from boiled cotton linters, more than 75% whiteness is achieved in a single-stage process using oxygen. The bleaching is conducted using the oxygen obtained by disproportionation of peroxo compounds in the pH range from 6 to 13 and with the bleaching time, depending on the bleaching temperature of 35.degree. C. to 15.degree. C., being between 15 and 150 minutes.

Bleaching using oxygen is already known, with the most important bleaching agents being hydrogen peroxide and sodium peroxide. Sodium perborate (NaBO.sub.3 .multidot.4 H.sub.2 O) is also of great importance, but has not been used in industrial bleaching for economic reasons; however, it has been used as a component of automatic detergents.
Peroxyacetic acid has posed handling difficulties in previous processes and has been used to a very limited extent for bleaching naphthol-dyed textiles. Potassium persulfate has also been proposed for bleaching as has sodium persulfate, as an additive in peroxide bleaching.
Molecular oxygen has likewise been used successfully as a bleaching agent in the MODO and SAPPI processes, with oxygen treatment taking place in the presence of NaOH at a temperature of approximately 100.degree. C. To suppress over oxidation of the cellulose, MgCO.sub.3 or complex manganese compounds are used.
Known bleaching processes using oxygen and peroxo compounds require temperatures of at least 100.degree. C. and a generally highly alkaline medium generally produced by using alkali hydroxides.
Activation and stabilization are critical for the bleaching process.
The purpose of stabilization is to prevent radical decomposition of hydrogen peroxide and to render inactive any catalyst present which may promote this breakdown.
One stabilizer commonly employed in peroxide bleaching is water glass, often used in combination with magnesium salts. Other stabilizers include magnesium salts together with dispersing agents or complex formers. Other known stabilizers for hydrogen peroxide are phosphorus salts such as Na.sub.2 H.sub.2 P.sub.2 O.sub.7.
Activation is effected by raising the temperature, alkalinity, and concentration. Activation begins and accelerates the bleaching process, but also favors the occurrence of undersirable side reactions, especially the breakdown of cellulose.
Disproportionation of peroxo compounds proceeds for H.sub.2 O.sub.2 for example according to the following general reaction formula: ##STR1##
Two O atoms have increased their oxidation number by +1; two O atoms have reduced their oxidation number by -1.
The same is true for the disproportionation of peroxo acids, for example peroxoacetic acid. ##STR2##
If disproportionation of the peroxo compounds does not take place through radicals, molecular oxygen is then released in a form which initiates oxidation reactions at low temperatures. As a result, oxygen form disproportionation which does not proceed through radicals permits a very protective form of oxidation, avoiding side reactions.
A chlorine-free multistage cellulose bleaching process is known form DE-OS 22 19 505, with at least three bleaching stages being used, with bleaching conducted using a peroxide in the first stage, a peracid in the second stage, and again, a peroxide in the third stage. This process uses neither chlorine nor water glass. NaOH is preferably used as the base, with the bleaching temperature being 20.degree. to 140.degree. C., preferably between 40.degree. and the boiling point of the bleaching bath.
Under these conditions, decomposition to oxygen radicals also takes place, which then initiates largely uncontrolled oxidation by the oxygen radicals.
Bleaching which is completed in a short time with oxygen from disproportionation that does not proceed through radicals does not take place here. Bleaching times for each stage are four hours at about 70.degree. C. and about 20 minutes at 100.degree. C.

Oxygen bleaching of cotton linters by disproportionation of hydrogen peroxide


A printing mechanism requires ribbon spools to be locked in place radially, and includes a pivoting ribbon tension arm that must be pivoted out of its normal operating position when ribbon is to be replaced. A ribbon spool lock assembly includes a rotating locking hub on the side of the printing mechanism. The rotating locking hub includes a locking feature that protrudes into the printing mechanism to radially lock the ribbon spool when the locking hub is in a locked position. A pivoting lock arm is provided for pivoting the locking hub into an unlocked position in which the locking feature is disengaged from the ribbon spool.

1. Field of the Invention
The invention relates to offset-type printing mechanisms for high-speed printing of magnetic ink character recognition (MICR) symbols which use a conventional spool of print ribbon.
2. Background Art
Offset-type printing mechanisms typically require that depleted spools of ribbon media be replaced at regular integrals by less-skilled personnel. Because such printing mechanisms typically include spring tensioner, guide and locking elements to ensure correct installation, location and control of the ribbon and ribbon replacement mechanisms must be designed with an eye to swift, self-evident and foolproof ways of replacing ribbon for minimum downtime.
Existing approaches fail to address all of these concerns. Existing approaches typically require operators to learn and remember a specific routine of steps for ribbon replacement, deviation from which will lead to problems.
For the foregoing reasons, there is a need for an improved ribbon spool lock assembly for use in offset-type printing mechanisms.


Light sheet microscope for recording 3D images of a specimen, comprising a light sheet generator, an objective lens, an image detector and a wavefront encoder element or system positioned between the objective lens and the image detector for extending the depth of field of the objective lens. By doing so, the restriction on the distance between the collecting objective and the light sheet is relaxed, allowing the use of a light sheet scanning unit. The resulting light sheet microscope allows for a robust, aberration insensitive, fast 3D imaging without the need to move or perturb the specimen.

The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section.
Light sheet microscopy (LSM) is a technique in which an specimen under investigation is illuminated with a sheet of laser light such that the fluorescence emitted from the specimen is recorded in the orthogonal direction with an image detector (such as a CCD, CMOS, sCMOS cameras or equivalent/similar). Optical sections are obtained by moving the object, which can then be combined to obtain a 3D representation of the object.
LSM has wide range of variants that have been developed in recent years, adopting names such that Selective Plane Illumination Microscopy (SPIM), Ultramicroscopy, Digital Scanned Laser Light Sheet Fluorescence Microscopy (DSLM), Orthogonal Plane Fluorescence Optical Sectioning (OPFOS), Thin Laser Light Sheet Microscopy (TLSM), Objective Coupled Planar Illumination (OCPI), among others. (See, e.g., Siedentopf, H. & Zsigmondy, R., Ann. Phys.-Berlin 10, 1-39 (1902); Voie, A. H., et al., J. Microsc.-Oxf. 170, 229-236 (1993); Fuchs, E., et al., Opt. Express 10, 145-154 (2002); Huisken, J., et al., Science 305, 1007-1009 (2004); Holekamp, T. F., et al., Neuron 57, 661-672 (2008); Dodt, H. U. et ai, Nat. Methods A, 331-336 (2007); Huisken, J. & Stainier, D. Y. R., Developments, 1963-1975 (2009); and Keller, P. J. & Stelzer, E. H. K., Curr. Opin. Neurobiol. 18, 624-632 (2008), and patents US2012098949 A1, US 20070109633 A1, EP 2444833 A1 and EP 2494399 A2, the disclosures of each of which is incorporated herein by reference).
All the set-ups for LSM to date come with a number of problems:                The alignment is critical. The distance of the objective to the light-sheet must be set with a precision of microns within the DoF of the objective, and the light sheet must be at 90° from the optical axis of the collection objective.        A change of the collection objective requires realignment and adjustment of the distance between the object and the light sheet.        Changes in the internal refractive index of the specimen effectively change the focal distance of the objective and can induce deformations, curvature and other inhomogeneities of the light sheet. These may result in a loss of focal position and therefore in a blurred image.        To obtain a 3D image                    The object needs to be moved (either in the z direction or rotated).            Both the light sheet and the collection objective must be scanned (displaced) in the z direction, always maintaining constant the distance with the light sheet.                        Both of these induce mechanical movements or pressure waves that may interfere with the specimen and the measurement.        All the above mentioned points prevent the technique to be used for fast 3D imaging of biological specimens. Moreover, for in-vivo imaging the movement can perturb the specimen behaviour and development, resulting in an invasive technique.
It is desirable for an imaging system to overcome the problems described above.

Light sheet-based imaging device with extended depth of field

Fundacio Institut de Ciencies Fotoniques


A reception device includes an estimating unit, a rank identifying unit, a stream-number determining unit, a precoding-matrix determining unit, and a transmitting unit. The estimating unit receives a known signal transmitted from a transmission device, and estimates a channel between the transmission device and the wireless communication device and a reception signal quality. The rank identifying unit identifies a rank of a propagation path based on the estimated channel. The stream-number determining unit determines the number of data streams based on the estimated reception signal quality and the identified rank. The precoding-matrix determining unit determines a precoding matrix based on the estimated reception signal quality and the determined number of data streams. The transmitting unit transmits information relating to the determined number of data streams and the determined precoding matrix to the transmission device.

Multi-input and multi-output (MIMO) communication systems in which a transmission device and a reception device perform communication using an antenna array having multiple antennas have been known. Moreover, with the recent increase of communication band, communication using millimeter-waves has been considered to be applied. The millimeter-waves have large space propagation loss compared to electric waves of ultra-high frequency (UHF) band. Therefore, in the communication using millimeter-waves, the MIMO communication technique is applied to perform beam forming, thereby improving the communication quality.
Moreover, in the MIMO communication system, a wireless communication system in which a radio frequency (RF) precoding matrix including a phase shift relative to a transmission signal and a baseband precoding matrix to pre-code a transmission signal in a baseband are calculated has been known. In such a wireless communication system, a data signal having the number of data streams according to a rank acquired from a channel between a transmission device and a reception device is pre-coded by the calculated precoding matrix, and transmitted from the transmission device to the reception device. Related-art example is described in Japanese National Publication of International Patent Application No. 2014-526191.
When a data signal is transmitted from the transmission device with the number of data streams according to the rank, depending on a propagation environment between the transmission device and the reception device, the data signal received by the reception device can include many errors. In this case, retransmission of the data signal occurs frequently, and the throughput of data transmitted by the transmission device decreases. On the other hand, depending on a propagation environment between the transmission device and the reception device, a data signal can be received including a small number of errors by the reception device even if the data signal is transmitted with the number of data streams larger than the number of data streams according to the rank. However, as the number of streams is fixedly determined according to the rank, the throughput remains at a certain value, even though there is a possibility of improvement in the throughput.

Wireless communication device, wireless communication system, and transmission-data control method


An electrical machine may include a plurality of stator coil ends each having a fluid passageway therein. The electrical machine may further include a plurality of rings and a plurality of axial connector assemblies for connecting the plurality of stator coil ends to the plurality of rings. Each axial connector assembly may include a header cap including an open end received on a respective stator coil end and a closed end opposite the open end, the closed end defining a coil spherical connector portion. The header cap may have a fluid port therein coupled to the fluid passageway of the respective stator coil end. A ring spherical connector portion may be carried by a respective ring, and a pair of connector members may receive therebetween the coil and ring spherical connector potions.

An example of relatively large electrical machinery is an electrical generator driven by a turbine in a power generating plant. The electrical generator generally includes a rotor, and a stator surrounding the rotor. Stator windings or coils extend outwardly to the ends of the stator. The stator coil ends are connected to parallel phase rings at the end of the stator.
The size and configuration of an electrical generator generally requires that, to facilitate the installing or replacing of stator coils of the generator, the stator coils be arranged in physically separate coil sections, or halves. After they are set in their appropriate location, the stator coils need to be electrically and mechanically connected to one another at their ends. Similar connections may also be used between the ends of each phase coil. Maintaining consistently reliable series and phase connections between such coil ends is an important consideration both from a mechanical and an electrical standpoint.
It is known to use brazing techniques to affix connectors, such as made up of solid copper bars, to each coil end. This can provide effective series and phase connections between the coil ends. However, such techniques may be time-consuming and could take several days for performing a service rewind operation, even for experienced and skilled service personnel.
U.S. Pat. No. 4,894,575 to Nilsson et al. discloses an electrical generator connection to connect coil ends in series. A header cap having a spherically shaped end portion is brazed to each coil end to be connected. The spherically shaped end portion includes a top coil water hose nipple in the center thereof to allow fluid for cooling to pass therein. A pair of connector bars, each having similarly sized spherical seats, receives the spherically shaped portion of each coil end header cap. Electrical and mechanical connections are provided by bolting two connector bars together.
Similarly, PCT Publication No. WO2006/063186 discloses a bolted spherical series and phase connector for stator coils. A header cap having a spherically shaped end portion with a fluid port centrally located therein is brazed or connected to each stator coil to be connected. A pair of connector bars, each having similarly sized spherical seats, receives the spherically shaped portion of each coil end header cap. Electrical and mechanical connections are provided by bolting two connector bars together.
Still, the above connecting techniques may not be time-saving, especially when connecting a stator coil to a parallel ring in performing a service rewind operation. This time can be further extended for performing a rewind operation on a non-OEM generator, where an existing parallel ring is not positioned serially, or in a top-bottom configuration. In this case, the techniques already known do not apply, as they apply to a radial connection for stator coils. Thus, there is a need to reduce the time for performing such operations.

Electrical machine including axial connector assemblies and related methods


The present invention relates to methods and compositions for assaying embryonic stem cell maintenance. In particular, the present invention provides reporter constructs for stem cell pluripotency and differentiation and cells and organisms containing such constructs.

Recent published reports on the isolation and successful culturing of the first human pluripotent stem cell lines have generated great excitement and have brought biomedical research to the edge of a new frontier (National Institutes of Health, Office of the Director, "Stem Cells: A Primer"). Stem cells have the ability to divide for indefinite periods in culture and to give rise to specialized cells. They are best described in the context of normal human development. Human development begins when a sperm fertilizes an egg and creates a single cell that has the potential to form an entire organism. This fertilized egg is totipotent, meaning that its potential is total. In the first hours after fertilization, this cell divides into identical totipotent cells. This means that either one of these cells, if placed into a woman's uterus, has the potential to develop into a fetus. In fact, identical twins develop when two totipotent cells separate and develop into two individual, genetically identical human beings. Approximately four days after fertilization and after several cycles of cell division, these totipotent cells begin to specialize, forming a hollow sphere of cells, called a blastocyst. The blastocyst has an outer layer of cells and inside the hollow sphere, there is a cluster of cells called the inner cell mass.
The outer layer of cells will go on to form the placenta and other supporting tissues needed for fetal development in the uterus. The inner cell mass cells will go on to form virtually all of the tissues of the human body. Although the inner cell mass cells can form virtually every type of cell found in the human body, they cannot form an organism because they are unable to give rise to the placenta and supporting tissues necessary for development in the human uterus. These inner cell mass cells are pluripotent—they can give rise to many types of cells but not all types of cells necessary for fetal development. Because their potential is not total, they are not totipotent and they are not embryos. In fact, if an inner cell mass cell were placed into a woman's uterus, it would not develop into a fetus.
The pluripotent stem cells undergo further specialization into stem cells that are committed to give rise to cells that have a particular function. Examples of this include blood stem cells, which give rise to red blood cells, white blood cells and platelets; and skin stem cells that give rise to the various types of skin cells. These more specialized stem cells are called multipotent.
While stem cells are extraordinarily important in early human development, multipotent stem cells are also found in children and adults. For example, consider one of the best understood stem cells, the blood stem cell. Blood stem cells reside in the bone marrow of every child and adult, and in fact, they can be found in very small numbers circulating in the blood stream. Blood stem cells perform the critical role of continually replenishing our supply of blood cells—red blood cells, white blood cells, and platelets—throughout life. A person cannot survive without blood stem cells.
Multipotent stem cells have not been found for all types of adult tissue, but discoveries in this area of research are increasing. For example, until recently, it was thought that stem cells were not present in the adult nervous system, but, in recent years, neural stem cells have been isolated from the rat and mouse nervous systems. The experience in humans is more limited. In humans, neural stem cells have been isolated from fetal tissue and a kind of cell that may be a neural stem cell has been isolated from adult brain tissue that was surgically removed for the treatment of epilepsy. In animals, it has been shown that some adult stem cells previously thought to be committed to the development of one line of specialized cells are able to develop into other types of specialized cells. For example, recent experiments in mice suggest that when neural stem cells were placed into the bone marrow, they appeared to produce a variety of blood cell types. In addition, studies with rats have indicated that stem cells found in the bone marrow were able to produce liver cells. These exciting findings suggest that even after a stem cell has begun to specialize, the stem cell may, under certain conditions, be more flexible than first thought.
Research on human adult stem cells suggests that these multipotent cells have great potential for use in both research and in the development of cell therapies. For example, there would be many advantages to using adult stem cells for transplantation. If one can isolate the adult stem cells from a patient, coax them to divide and direct their specialization and then transplant them back into the patient, it is unlikely that such cells would be rejected by the patient's immune system. The use of adult stem cells for such cell therapies could reduce the practice of using stem cells that were derived from human embryos or human fetal tissue, sources that trouble many people on ethical grounds.
Stem cells can be made to differentiate under certain culture conditions. However, in some applications it is desirable to maintain stem cells in a non-differentiated state. Additional methods for assaying the differentiation status of stem cells are needed.

Embryonic stem cell self maintenance and renewal reporter

The Trustees of the University of Princeton - Princeton University


A gaming table is disclosed according to which players in a table type game make their wagers by using chips that are embedded into the table. The table has apertures, with each aperture having an electro-mechanical device incorporated. Mounted on each electro-mechanical device is an adjustable elongated column graphically divided into sections resembling a stack of betting chips that are associated with each player to represent chips belonging to and wagered by each said player. The table also has manually operated switches associated with each player. The switches are electrically connected to corresponding electro-mechanical devices such that when switches are operated certain electro-mechanical devices move their corresponding elongated columns relative to its aperture simulating the increasing or decreasing of the number of chips in stacks associated with each said player. The manually operated switches are capable of causing the readjustment of all said elongated columns.

Table type games are known in which players use chips or coins for wagering. Generally, each player arranges his chips in one or more vertical columns on the tabletop directly in front of him. In a poker game for instance, after a number of cards are dealt to all players, the first player to act makes a wager by moving to a designated betting area in front of him a number of chips that represent the nominal betting amount established for the game, or any portion of it that he possesses. Each of the following players to act in sequence then has the option to call, raise or pass. A player calls by moving to a designated betting area in front of him a number of chips equal to the highest number of chips wagered by any of the preceding players, or any portion of it that he possesses; raises by moving to said designated area a number of chips equal to the sum of the highest number of chips wagered by any of the preceding players and the number of chips representing the nominal betting amount, or any portion of it that he possesses; or passes by folding his cards and forfeiting the game. The sequence is repeated, starting with the player that originated the betting sequence, each time a raise is made by any player, until all remaining active players have wagered the same number of chips, completing a betting cycle. The chips wagered are then moved from the individual designated betting areas to a common betting area near the center of the table by a designated dealer. The chips are generally arranged in separate groups and sub-groups that each player is entitled to win in proportion to his wager when wagers are made in disproportionate amount by different players. The betting process is repeated each time a new card is dealt to the remaining players, with the designated dealer separating the chips wagered as previously described, until all but one player has exercised the pass option or the maximum number of betting cycles established for the game has been reached, ending the game.

Apparatus for using embedded chips in a gaming table


A captured digital image is stored in memory together with metadata derived from a location signal only if the location metadata is determined not to be within one or more predefined exclusion zones. A GPS receiver module can be implemented to obtain the location signal.

Today, through use of digital cameras, consumers are able to easily capture and store large collections of personal digital images. These image collections can be stored either locally on a personal computing device or stored remotely on an online photo-management service such as Kodak Gallery, which are capable of maintaining digital image collections for a large number of users and enable users to share their digital images with other users via the internet.
Digital images are composed of pixel data which is used to render a two dimensional digital image on an electronic display or in printed hard copy form. In addition to pixel data, digital images often further include metadata which is data related to and associated with the digital image. Metadata is often useful for organizing and searching of digital images. Some metadata can be provided automatically when the image is first captured by a digital camera device, such as for example, capture date and time metadata. Other types of metadata may include metadata entered by the user such as a caption or 'favorite' designation. Other types of metadata may be provided by photo-management software such as a last edited date and time. Another example of metadata is people tag metadata identifying one or more people appearing in the digital image. People tag metadata can be entered either manually by a user or automatically by photo-management software, for example by using facial recognition algorithms.
Another type of metadata which can be associated with digital images is location metadata, such as longitude and latitude coordinate metadata. Location metadata may similarly be provided at the time the image is captured, for example by a digital camera device with a Global Positioning System (GPS) sensor. Alternately, a user may manually enter location metadata at some time after the image has been captured. Location metadata is also useful for organizing a collection of digital images. For example, commonly assigned U.S. Pat. No. 6,883,146 describes a graphical user interface (GUI) system for browsing and retrieving digital images by location. This patent is incorporated herein by reference in its entirety.
However, some users do not always want their digital images to include location metadata. Particularly, a user may wish to not include location metadata when sharing digital image files with other users or when publishing digital images publically, for example on an internet website. Users might, for example, want to publish an image captured at their home, but not necessarily provide the precise latitude and longitude coordinates of their home address.
In order to address this concern, some GPS-enabled cameras provide the ability to disable the location metadata feature so that metadata is not automatically saved every time a picture is captured. However, if the user wants some digital images to include the location metadata and others to not include the location metadata, the user must remember to turn on and off this setting prior to taking each picture. Alternately, the user may use photo-management software currently available to remove the location metadata prior to sharing or publishing each digital image. However, the user must also remember to do this and may not always be aware which digital images in his or her collection include such location metadata. Alternately, some photo-management services allow a user to specify privacy based on which other users can view location metadata for one or more pictures. However, the user must again actively manage which photos have location information shared for each image or group of images where the user wishes to have privacy. As a result, these known methods of addressing the privacy concern with location metadata can result in some images undesirably being shared or published with location metadata or some images undesirably captured without location metadata. An improved system for managing the privacy of digital images having location metadata is therefore desired.

Method for managing privacy of digital images


The present invention addresses an ATV clamp assembly. The clamp assembly includes a central body having a handlebar leg and a hand guard leg, a handlebar clamp pivotally connected to the handlebar leg and removably clamped to the ATV's handlebar and a hand guard member pivotally connected to the hand guard leg and removably connected to the hand guard. Also addressed is a motorcycle clamp assembly including a handlebar clamp removably connected to the motorcycle's handlebar and having a generally rectangular shape with rounded ends and having a tapered aperture configured to mate with handlebar's tapered portion, and a hand guard member connected to the hand guard and pivotally connected to the handle bar clamp. A method for manufacturing hand guards is disclosed. Using that method, one or more bends are cut in the X-Y plane and a bender is used to form at least one bend in the Z-axis.

Clamp assemblies exist for connecting a hand guard to the handlebar of all-terrain vehicles (ATVs). In the past, however, such clamps were specifically designed to be used with a particular model ATV. To meet customer demand for ATV clamps, a store must carry a variety of clamps, which requires a corresponding amount of storage and display space. Specifically designed clamps also are disadvantageous for the ATV owners. When clamps are designed to fit a specific ATV, the proper clamp must be purchased. As with replacement wiper blades, if the wrong clamp is purchased, the customer must return it to the seller and exchange it for the correct clamp. The same problems exist for motorcycle clamps, which are designed to fit specific motorcycle models.
Hand guards also exist for protecting the rider's hands. These handle guards generally are formed from elongate metal bars, which are bent using a conventional bender to form the desired shape. Using this method, however, each bend represents a structural weakness. More structurally robust handguards and methods for manufacturing them continue to be sought.


A system, method, and bit-stream format thereof for delivery, scalable encoded media data is described. The scalable encoded bit-stream is formatted to have first and second portions. The first portion corresponds at least to non-media type specific scalability attributes of the original encoded media data and data structure information of a second portion and the second portion corresponds to the original scalable encoded media data arranged in a non-media type specific indexable data structure having at least one dimension. The formatted media data allows the system and method to provide seamless, flexible delivery to media destinations having a variety of receiving attributes. The media data is transcoded prior to delivery based on the receiving attributes of the media destination and non-media specific scalability attributes of the formatted scalable encoded media bit-stream.

Users access the Internet today using devices ranging from handhelds to powerful workstations, over connections ranging from 56 Kbps modems to high speed 100 Mb/s Ethernet. Even though the available bandwidth, display and processing capabilities continue to grow, the heterogeneity and the spread of capabilities at any point in time are here to stay. On the other hand, as bandwidth and other factors grow, so does the richness of media that is delivered to users.
Under these circumstances, a rigid media representation format, producing decompressed content only at a fixed resolution and quality is clearly inappropriate. A delivery system based on such a compression scheme can only deliver content satisfactorily to a small subset of users interested in the content. The rest, either cannot receive anything at all, or receives poor quality and/or resolution relative to the capabilities of their network connections and/or accessing devices. The inability to cater to this diversity has been a determining factor that stunted the growth of new rich media, because such rich content can cater only to power users comprising a small fraction of the whole. Without adequate focus on seamless content adaptation, accessibility and usability of media will always be severely limited.
One known technique for providing media content to users having a variety of capabilities and preferences is to provide multiple versions of the media suiting a variety of capabilities and preferences. While this approach works with delivery models where the recipient directly connects to the media originator, for any other multi-hop, multi-recipient delivery scenario, too much redundancy and inefficiency is introduced, leading to wastage of bandwidth and storage. This is especially so, when the media creator wishes to provide a wide range of choices catering to a large consumer base, and therefore needs to maintain a large number of versions differing in a variety of ways.
In order to combat the above problem, scalable compression formats have been proposed. Scalable compressed representations can accommodate all users by automatically maximizing the multimedia experience for a given user's computing power and connection speed. By adapting rich media content written for high-end machines with fast connections, to less powerful machines with slower connections, the overheads involved in producing different versions as described above for different scenarios can be virtually eliminated. Furthermore, content created today at the highest possible quality, remains 'timeless' when represented in a scalable format, and the experience it provides gradually increases, as the power of machines and connection speeds improve.
One example of a scalable compressed representation is JPEG2000. JPEG2000 is a scalable standard for still images and endeavors to combine quality scalability and resolution scalability in a format specific to JPEG2000 compressed data, to enable distribution and viewing over a variety of connections and devices. However, in order to obtain the benefits of the scalability of the format, it is necessary to develop and deploy an infrastructure that specifically supports transcoding of JPEG2000 content and delivery to a heterogeneous recipient base.
In recent years, a great deal of attention has been focused on delivering streaming video over the Internet or wireless. Hence, video standards of MPEG-X (mostly MPEG-4) and H.26X families were developed that incorporate various forms of scalability for delivering media content such as streaming video to a heterogeneous recipient base. However, this type of scalable video over the Internet is limited to maintaining multiple versions for a few different types of connections, because complete infrastructures that support transport of scalable video formats are non-existent.
Any infrastructure, is expensive to deploy, and requires significant financial commitments from the patron companies or patron consortia. In order to guarantee constancy of the format it would also be desirable that the format the content is represented in be standardized. On the other hand, standards take several years to come into effect, typically much longer than is commensurate with the normal pace of change in the multimedia industry. As new types of media beyond traditional images, video and audio evolve; it would become more and more difficult to expect standards to support their representation. Even if scalable formats evolved for every new type of media, the inevitable difference in the structure of the content would necessitate use of different infrastructures for scalable delivery of different types of media. The expenses involved present a very formidable obstacle in adoption of such new media and supportability of its scalability features.
There are various types of bit-stream scalability that can be devised depending on the type of media. For example, SNR (quality) scalability refers to progressively increasing quality as more and more of the bit-stream is included, and applies to most types of media. Resolution scalability refers to fineness of spatial data sampling, and applies to visual media such as images, video, 3D etc. Temporal scalability refers to fineness of sampling in the time-domain, and applies to video and other image sequences. There are several types of scalability pertaining to audio, such as number of channels and sampling frequency and so on. In the future, with the evolution of newer, richer and more interactive types of media, there will be newer types of scalability that are, to date, unknown. A scalable bit-stream does not always have a single type of scalability. Different types of scalability can co-exist, so as to provide a range of adaptation choices.
In new rich media, different media elements are often bundled together to provide a composite media experience. According to one known technology, an image with audio annotation and some animation provides a composite experience of a presentation using three media elements (an image, an audio clip, some animation data). Composite rich media models such as this lead to newer types of scalability specific to the media, because certain non-critical elements of the composite may be dropped to accommodate other more critical ones within the limited resources of a recipient.
The present invention provides a system, method, and format thereof for scalable encoded media data delivery to a heterogeneous recipient base and that is not specific to the type of media being delivered thereby requiring a single delivery infrastructure for delivering all types of currently known media and future media.

System, method, and format thereof for scalable encoded media delivery

Hewlett-Packard Development Company, L.P.


A power conversion system includes first and second voltage sources for driving a multiple-phase AC motor and a control unit. The control unit is configured to compute first and second output voltage command values used to drive the multiple-phase AC motor based on a first output voltage command vector corresponding to the voltage source that is charged and a second output voltage command vector corresponding to the voltage source that is discharged. The first and second output voltage command vectors are determined so that a resultant vector of the first and second output voltage command vectors is coincident with a motor voltage command vector corresponding to a motor voltage command value, and a motor current command vector corresponding to the motor current command value is positioned within an included angle formed between the second output voltage command vector and a negative vector of the first output voltage command vector.

1. Field of the Invention
The present invention relates to a power conversion system and a power conversion control method.
2. Background Information
Japanese Laid-Open Patent Application Publication No. 2006-33956 discloses an example of a known motor drive system control apparatus that uses a plurality of power sources that supply electric power to an electric motor and that controls the electric power supplied from each of the power sources to a desired value. With the control apparatus disclosed in this reference, a voltage command value applied to the motor is divided according to the ratio of the distribution target values of the electric power outputted from the power sources to produce a second voltage command value group.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved power conversion system and power conversion control method. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.

Power conversion system and power conversion control method


Method for locating metal studs hidden from view by wall board members fastened thereto by screw-type fasteners characterized by a magnetic field of force which attracts particulate magnetic material, by first locating the screw-type fasteners which are hidden from view by spackling compound or other wall surface finishing material. The screw-type fasteners are located by depositing particulate magnetic material on the outer surface of the wall board, the particulate magnetic material being attracted to a screw-type fastener by the magnetic field of force and associating with the head of the fastener in a surrounding manner on the outside surface of the wall board.

(1) Field of the Invention
This invention relates, in general, to apparatus for, and a method of, locating a metal stud covered over by, and located behind, a wall partition. Further, it relates to apparatus means and a method for locating the metal screws fastening wallboard or the like to metal studs so that such metal screws can be removed and the wallboard then removed essentially intact.
(2) Description of the Prior Art
With more recent building practices, particularly in commercial buildings, it has become somewhat common to provide metal, rather than wooden, studs or upright members in the outer or inner walls of the building. Nevertheless, the use of metal studs is not limited just to commercial buildings. Such members are rather commonly used in new, residential housing construction, and in rehabilitation of older building structures, e.g. in the conversion of schools and other structures to condominiums. In such cases as last mentioned, the old walls may, in fact, be left standing with metal studs and new wall structures merely attached thereto.
Regardless of the building structure involved, once the metal studs are installed, the next step is to install the wall surface members. Thus, to these metal studs are then fastened the panels or wallboard members, e.g. the commonly so-called "dry walls" or other wallboard forming the wall surface. The wallboard members are fastened to the metal studs by a plurality of vertically disposed spaced apart metal screws that are driven through the wallboard member into the upright metal studs which are spaced apart from one another in horizontal disposition along the length of the wall e.g., 16 inches, center stud to center stud. These metal screws are commonly driven into the wall by an electric drill. Nevertheless, the screw heads are generally recessed and taped or spackled over, after which they are hidden, in anticipation of painting or otherwise finishing the walls.
Once a wall is installed and finished, it is sometimes most difficult to locate the concealed metal studs. Nevertheless, it may become necessary from time-to-time for various tradespersons such as carpenters, electricians, cabinet installers, etc., to locate the studs or a particular stud, for various desired purposes. In some cases, it may be desirable to locate all the metal studs behind a particular wall surface and the metal screws holding it so that such a wallboard or the like can be removed intact and later re-installed. Such may be the case where an electrician or plumber may need determine the existence and location of wiring or piping behind a wall surface. Or, when demolishing a building, it may be desirable to remove a wall intact rather than destroying or mutilating it for safety or environmental reasons, e.g., where asbestos is of concern. Even a homeowner may from time-to-time desire to locate a particular stud in a wall to use such as a foundation for mounting objects, e.g. pictures, on the wallboard or other outer surface.
There are, in general, three methods of which I am aware used for locating wall studs. The most fundamental method used is to tap the wall with a hammer at spaced-apart locations horizontally while listening to the sound made, attempting thereby to sense a relatively solid sound which occurs when the hammer is tapped on the wallboard directly in front of a wall stud. This method is mostly trial and error and is sometimes quite frustrating. Although damage to the wall, if any, is generally slight, e.g., dents and scratches, and relatively easily repaired in most cases, a wall stud may be completely missed, depending on the interval or distance apart of the striking locations. Thus, it may be necessary for a person to go over the same wall distance several times, at different tapping intervals, before sensing what appears to be a solid sound. Also, some individual's ears are more attuned to sound differences than others. It is not unusual, moreover, to mistake a solid sound, and to drive a nail into the wallboard only to realize that the stud's location has been missed entirely, or only its edge has been located. When the stud is missed entirely, one must try to locate the stud once again by tapping at different intervals and a nail must again be driven into the wallboard at chosen locations to determine if the hidden stud has been located.
A second method is to drive a nail through the wallboard at spaced locations along a horizontal line until a wall stud is finally encountered. This method is somewhat akin to the first method and suffers from the same disadvantage. Seldom is one able to choose the correct spacing or interval, in the first place, to locate the stud immediately. Thus, the spacing between "nail holes" may need be adjusted, more or less, until a portion of the stud at least is located. Once a stud is located, its horizontal extents and its center line can then, however, be readily determined. And once the centerline of one stud is located, other studs can then be located provided such are properly located on standard centers. The main disadvantage with this method of locating studs is that it is not only somewhat frustrating but such method necessarily involves physical damage to the wall surface. Each of the nail holes driven into a wallboard not located over a stud must, in general, be plugged, and then painted over, or the wall otherwise finished depending upon the particular wall covering involved. Such a method is not at all desired where the wallboard is papered over. Moreover, although it may be possible to locate a stud by this method, and the method first described, neither is of any help in locating the nails or screws that may have been driven into the wallboard fastening such to the stud.
A third method of locating wall studs involves the use of so-called "stud finders". These devices typically comprise, in general, a magnet supported in a manner to pivot in the presence of magnetic material, e.g. a nail driven through wallboard into a wooden stud. Exemplary of such prior art devices are U.S. Pat. Nos. 2,933,679; 3,293,544; and 3,363,208. None of these patents, however, disclose a device such as is contemplated by my invention. Neither could any of the devices disclosed be used, it is believed, to locate a metal screw driven into a metal stud.
U.S. Pat. No. 2,933,679 discloses a stud finder which makes use of the concept that certain materials of ferrous metal, e.g., nails, screws, or the like are attracted to a magnetic. Thus, in general, the stud finder disclosed comprises an elongated magnet mounted for rotation within a housing. In use, the stud finder is simply grasped by the hand and is moved horizontally along the wall. As a hidden nail holding a wall board to a wooden stud is approached, the pivotally supported elongated magnet will pivot and will align itself with the embedded nail. Although such a device might be helpful in locating a metal stud itself, as desired in part herein, the device will not, however, be found useful to locate the metal screws driven into a metal stud. This is because the magnet in the stud finder device will, it is believed, be attracted to the stud itself, not being able to distinguish between the metal stud and the metal screws located therein. Thus, locating the metal screws in a metal stud for removing such and the wallboard intact would still be largely a hit-and-miss operation. Moreover, the device disclosed in that patent includes a magnet searching, in a sense, for metal attracted thereby whereas my invention does not operate in such a fashion. As disclosed more fully later, my invention instead provides metal particles that are attracted to the metal screws located in the metal stud, and as such the metal screws act like magnets.
In U.S. Pat. No. 3,293,544, there is disclosed a nail detector using metallic particles. The nail detector comprises, in general, a spool located within a case, having a transparent outer face. The spool has a centrally disposed opening which extends from adjacent the transparent outer face to the rear face of the case which is in contact with a wall. A coil is provided upon the outer circumference of the spool connected to a source of electric current. When the coil is electrically energized it creates a magnetic field and magnetically exercises a plurality of iron filings seen through the transparent face. The case is moved along the wall while the iron filings are energized. As a result, when the opening in the spool passes over a hidden nail head, the iron filings will have a tendency to collect over the nail head, due to the nail being magnetized. The inner wall of the spool surrounding the opening, however, and at the location of the nail head, will permit the iron filings only to gather around the opening. When a nail head is so located, a pencil is inserted into the opening whereby to make a mark on the wall, at the location of the nail head. Such a device as disclosed in the patent, however, could not be used, it is believed, to locate the metal screws previously driven into a metal stud. It could not distinguish the metal screw from the metal stud.
U.S. Pat. No. 3,363,208 discloses a stud finding device wherein an elongated multiple magnetic sensor provides discernible deflection towards a nail head by one and generally two of a set of vertically mounted magnets pivotally mounted within the sensor. Thus, a plurality of elongated magnets are mounted one above the other, along the length of a U-shaped body member, open at one face. Each magnet is mounted at its top edge for pivotal motion toward the open face, placed against a wall, when a nail is encountered, as the elongated stud finding device is moved along a wall in a vertically upright manner. As the stud finder passes a stud, ordinarily at least two nails will cause a magnet to pivot inwardly toward the nails. This action can be readily detected by feel or observed where the back edge of the body member is of a transparent material. Such a stud finding device is of no use, however, in locating the individual metal screws fastening the wallboard to the metal studs, and which screws are hidden from view behind spackling compound, tape and paint.

Method for locating metal studs hidden behind a wall partition by use of particulate magnetic material


One embodiment is a display apparatus kit that has a wall support configured to be selectively coupled to a wall and at least one tubular divider configured to be coupled to the wall support. Wherein, the divider is coupled to the wall support to define a slot, the slot is sized to receive and maintain merchandise in an orientation that is beneficial to a user.

It is common practice for commercial and retail stores to use large shelving units to display the products that are sold. The shelving units often consist of a strong center member or wall that goes along the length of the aisle. The center member can act as a base for connecting many various shelving attachments. The shelving attachments are used to create a flat surface to set products on top of. Further, a hook or rail structure can be used to provide a means for hanging products on display from the center member.
The center member or wall must be adequately supported to prevent the center member from falling into the aisle. This is usually achieved by having a strong base section that provides support to the center member. The center member is also usually supported at the ends of the aisles by a second wall that is perpendicular to the center member. This second wall is often as wide as a longitudinal cross section of the shelving system and provides for additional support to keep the center member from becoming unstable.
In addition to providing needed support to the center member, the second wall is also an ideal space for displaying products. The second wall creates more exposure for a product than would the shelves along the center member because shoppers often walk along the exterior of the aisles prior to choosing an aisle that may contain the product they are looking for. From a marketing standpoint, displaying products on the second wall is ideal because it increases the exposure of the product to the customer.
With regards to animal beds or other similar products, using shelving along the aisle is not ideal. The animal beds are often too large to easily fit on the shelves. While the animal beds may be organized in an aesthetically pleasing fashion when the store opens, after consumers begin to remove the animal beds from the shelves they can become disorganized and hard to view. The current method of displaying animal beds is not ideal because it reduces the consumer's exposure to the animal bed by locating it on shelves within the aisles and it often results in a messy product display as consumers rummage through the various animal bed products.