In a device for the knotless joining of threads and yarns using compressed air, a chamber is provided including central region of substantially U or V cross-section, possibly with a flat base, and two lateral regions of substantially circular cross-section. The slits of the three regions, through which the yarns to be joined are inserted, form a continuous common gap which is closable frontally by a cover. A nozzle opens into the base of the central region in a direction perpendicular to the frontal opening of the slit of said central region, and a nozzle opens into the base of each lateral region opposite the frontal opening of the relative slit in a direction substantially tangential to the circular cross-section, these latter two nozzles being in opposing positions and feedable with compressed air via a duct which is separate from the feed duct for the nozzle opening into the central region.

This invention relates to a device for the knotless joining of threads and yarns using compressed air. These devices, commonly known as "thread splicing devices" are much used for joining threads and yarns, and have largely replaced the previously used knotting devices because of their numerous advantages over these latter.
It has been sought to continuously improve pneumatic splicing devices in order to make them suitable for an increasingly wide range of threads and yarns, including natural fibre, artificial fibre, monofilament, short fibre and long fibre types, to in each case achieve knotless joints of high tensile strength and of good appearance, so that they differ as little as possible from the strength and appearance of the original continuous thread or yarn. Various systems and methods are used to achieve this knotless joining. Pneumatic splicing is always carried out in a splicing chamber (also called a splicing channel) into which, after suitable prior pneumatic or mechanical treatment for removing the original twist of the threads and for opening and parallelizing their fibres, the ends of the threads to be joined together are inserted so that they lie partly superimposed one close to the other and are then subjected to short strong compressed air jets fed into the chamber through variously arranged apertures or nozzles.
One of these systems aims mainly at obtaining thorough mixing of the fibres forming the ends of the threads or yarns to be joined together so that they become effectively tangled and interlaced. To implement this system splicing chambers are used having substantially V or U cross-sections into which the compressed air jet or jets are fed from the base to directly strike the ends of the threads to be joined. As the chamber is in communication with the outside both at its two ends or lateral openings and via the front opening of a longitudinal slit through which the threads are inserted into the chamber, it is well known to close this front opening and hence the chamber during the splicing operation by a cover to prevent the thread ends escaping frontally through the opening of said longitudinal slit by the effect of the compressed air jets which strike them. In this case, under the effect of the jet or jets fed from the base of the chamber, the thread ends undergo violent undulatory action to strike the cover and the chamber base, so that their fibres are effectively interlaced to achieve a good strong knotless joint. However the appearance of the joint obtained suffers from the fact of individual fibres projecting from the sides of the joint.
It has been found that the result is much better if a substantially V or U-shaped chamber is used rather than a circular cross-section chamber, especially if not provided with a cover for the temporary closing of the front opening of its thread insertion slit.
Another system used aims more at mutual rolling-together of the thread ends to be joined, and uses mainly circular cross-section splicing chambers with compressed air feed nozzles arranged to cause rotary air circulation. In this case normally at least two opposing nozzles are used opening substantially tangentially into the circular chamber at points more or less close to the two ends or side openings of the chamber. This system, by which the joints are of excellent appearance because the end fibres of one thread are properly rolled about the other thread but are of less mechanical strength, requires that in arranging the nozzles by which compressed air is fed into the chamber, account be taken of the original twist of the yarns in the sense that they do not cause them to untwist but instead act in the same direction as their twist. The nozzle arrangement has therefore to be changed in changing from S to Z twist yarns to be joined. These briefly described known systems hence each has its advantages and defects.
It was therefore apparent that a system would be sought which combines all the advantageous of those previously used while at the same time eliminating their drawbacks. Attempts in this direction have been made known from the documents DE 32 40 485 A1, DE 34 11 482 A1 and DE 40 19 959 A1.
According to document DE 32 40 485 A1, a splicing device comprises a circular chamber with an oblique slit for inserting the threads to be joined, with two compressed air feed nozzles opening into the centre of the chamber from opposite sides, the first of these nozzles opening into the chamber from one side of said slit and being directed towards the longitudinal axis at the centre of the chamber and against its opposite wall, whereas the other nozzle opens into the chamber from the opposite side of the slit and is directed substantially tangentially to the circular chamber, the first nozzle being connected by a shorter duct and the second nozzle being connected by a longer duct to a common compressed air feed duct. The longitudinal slit through which the threads are inserted into the chamber is again open frontally and in communication with the outside. On feeding compressed air through said feed duct an air jet initially leaves from the first nozzle to interlace the fibres, and a moment later a supplementary air jet leaves from the second nozzle to roll the ends of the threads. The splicing operation takes place in two successive stages with a small delay between the first and second stages due to the different lengths of the ducts by which the compressed air is fed to the two nozzles, air being fed into the chamber firstly only from the first nozzle, and afterwards from both.
According to document DE 34 11 482 A1, the splicing device is improved in the sense that three nozzles are provided for feeding compressed air into the chamber (which is again of circular shape with a frontally oblique longitudinal slit always open for the insertion of the threads), of which one is positioned at the centre of the chamber and is directed towards its longitudinal axis and opposite wall, and the other two nozzles oppose each other and are displaced towards the respective ends of the chamber to open into it substantially tangentially. Compressed air from a single feed duct is fed to the three nozzles via a duct which partly surrounds the circular chamber. In this case the purpose of the central nozzle is to cause fibre interlacing and the purpose of the two opposing lateral nozzles is to roll the ends of the two threads in opposite directions. The arrangement of these lateral nozzles has to be determined on the basis of whether the threads to be joined are of S or Z twist.
Document DE 40 19 959 A1 proposes a further system improvement, consisting substantially of providing to the sides of the slit, through which the threads are inserted into the centre of the chamber, a first two opposing nozzles directed towards the longitudinal axis of the chamber and against its wall opposite said slit, and a further two mutually opposing nozzles displaced towards the respective ends of the chamber and opening into it substantially tangentially. The first two nozzles are connected by a common channel to a first compressed air feed duct and each of the further two nozzles is connected by its own channel to a common second compressed air feed duct. In this manner the order of compressed air feed into the chamber can be diversified so that it occurs firstly only through the first two nozzles and a moment later only through the further two nozzles.
These splicing devices proposed in the three aforesaid documents each have a chamber of circular cross-section constant from one end to the other, the chamber being in communication with the outside not only via its lateral openings but also frontally via the frontal opening of the always open slit through which the threads are inserted and which extends for the entire length of the chamber.
It has now been found that splicing devices of this type still suffer from various drawbacks deriving from the aforedescribed shape of the chamber. Firstly, the fibre interlacing achievable with the nozzle or nozzles directed towards the longitudinal axis of the circular chamber is not perfect in that it is not possible for the air jets leaving these nozzles to transmit the violent beating action and undulating movement to the two threads by which the fibres mutually mix, tangle and interlace. This is because the compressed air can also leave the chamber through the frontal opening of its slit through which the threads are inserted, so losing its effectiveness, and in addition the air jets leaving the nozzles directed towards the longitudinal axis of the chamber must always be directed against a solid opposite wall of the chamber and never against the front opening of said insertion slit, otherwise the threads are expelled from this opening.
In addition, the air jets fed substantially tangentially into the chamber have the same constant uniform cross-section over their entire length, and can therefore interfere with each other to make the rolling of one thread end about the other uncertain.

Device for the knotless joining of threads and yarns using compressed air


A lock has an actuating nut rotatable about an axis and formed with a radially extending guide, a bolt-controlling push rod slidable offset from the axis in a predetermined direction transverse to the axis, and a slide displaceable radially of the axis in the guide and having an outer end remote from the axis. A pin is engaged between the outer end of the slide and the push rod so that on rotation of the nut about the axis the slide and pin move angularly relative to the axis and the slide moves radially relative to the axis. The guide is a groove formed in the nut and he push rod is formed with a hole receiving the pin and the pin is fixed on the outer end of the slide.

The bolts of multibolt locks are either pushed in and out by means of a lock cylinder with the assistance of the pertaining key or by turning a latch from a normal horizontal position upwards for locking and downwards for unlocking. The latter latch-operable multibolt locks have gears between the nut and the push rod or rods, whereby one model uses space-saving gear segments for reasons of space economy. The cost of these models is high and it is difficult to achieve high efficiency with small overall dimensions. A multitude of toothed connections leads to a play which has a negative effect on the operation of the multibolt lock.


Method and apparatus for performing well operations, such as measuring or forming or testing or treating or the like, and combinations of the above operations, including the use of coiled-in-coiled tubing (CCT) connected to a bottomhole assembly package (BHA), such that the assembly is in communication with both fluid conduits (80 and 82) defined by the coiled-in-coiled tubing.

This invention pertains to safeguarded methods and apparatus for providing fluid communication with coiled tubing, useful in communicating fluids within wells, and particularly applicable to drill stem testing and/or operations in sour wells. The invention further pertains to multicentric coiled-in-coiled tubing, useful for safeguarded downhole or conduit operations, and its method of assembly, including preferred and alternate methods. The invention also pertains to the use of coiled-in-coiled tubing with a bottomhole assembly package for operations that may be particularly pertinent to horizontal and/or deviated wells, including operations such as treating or forming or testing or measuring and the like, and in particular, to combinations of the above operations performable in the same run.
This application is related to and comprises a continuation in part of prior pending application having PCT Serial Number PCT/US95/10007. The corresponding U.S. Ser. No. is 08/564/355.
The oil and gas industry uses various methods to test the productivity of wells prior to completing and tying a well into a pipeline or battery. After drilling operations have been completed and a well has been drilled to total depth (xe2x80x9cTDxe2x80x9d), or prior to reaching TD in the case of multi-zoned discoveries, it is common to perform a drill stem test (xe2x80x9cDSTxe2x80x9d). This test estimates future production of oil or gas and can justify a further expenditure of capital to complete the well.
The decision to xe2x80x9ccasexe2x80x9d a well to a particular depth, known as a xe2x80x9ccasing point electionxe2x80x9d, can result in an expenditure in excess of $300,000. Without a DST, a wellsite geologist must make a casing point election based on only core samples, cuttings, well logs, or other indicators of pay thicknesses. In many cases reservoir factors that were not knowable at the time of first penetration of the producing zone, and thus not reflected in the samples, cuttings, etc., can control the ultimate production of a well. A wellsite geologist""s problem is exacerbated if the well is exploratory, or a wildcat well, without the benefit of comparative adjacent well information. Further, the geologist must make a casing point election quickly as rig time is charged by the hour.
A DST comprises, thus, a valuable and commonly used method for determining the productivity of a well so that optimal information is available to the geologist to make a casing point election. Traditionally the DST process involves flowing a well through a length of drill pipe reinserted through the static drilling fluid. The bottom of the pipe will attach to a tool or device with openings through which well fluids can enter. This perforated section is placed across an anticipated producing formation and sealed off from the rest of the wellbore with packers, frequently a pair of packers placed both above and below the formation. The packer placement or packing off technique permits an operator to test only an isolated section or cumulative sections. The testing can involve actual production into surface containers or containment of the production fluid in the closed chamber comprised by the pipe, pressure testing, physically retrieving samples of well fluids from the formation level and/or other valuable measurements.
The native pressure in producing reservoirs is controlled during drilling through the use of a carefully weighted fluid, referred to above and commonly called xe2x80x9cdrilling mudxe2x80x9d. The xe2x80x9cmudxe2x80x9d is continuously circulated during the drilling to remove cuttings and to control the well should a pressurized zone be encountered. The mud is usually circulated down the inside of the drill pipe and up the annulus outside of the pipe and is typically made up using water or oil based liquid. The mud density is controlled through the use of various materials for the purpose of maintaining a desired hydrostatic pressure, usually in excess of the anticipated native reservoir pressure. Polymers and such are typically added to the mud to intentionally create a xe2x80x9cfilter cakexe2x80x9d sheath-like barrier along the wellbore surface in order to staunch loss of over-pressured drilling fluid out into the formation.
As can be easily appreciated, when an upper packer of a DST tool seals an annular area between a test string and a borehole wall, the hydrostatic pressure from the column of drilling fluid is relieved on the wellbore below the packer. The well below the packer, thus, can flow if an open fluid communication channel exists to the surface. At least the well will flow to the extent that native pressure present at the open formation of the isolated section exceeds the hydrostatic head pressure of the tested fluids in the drill pipe. Such produced fluids that flow to or toward the surface are either trapped in the pipe string or collected in a container of known dimensions and/or flared off. By calculating the volume of actual fluid produced, after considering such factors as the time of the test and the size of the choke used, a reasonable estimate of the ultimate potential production capacity of a well can be made. Upon occasion formation pores are too clogged, as by the drilling fluid filter cake, to be overcome by formation pressure and flow. It may be desired in such cases to deliver a gas or an acid to the formation to stimulate flow.
Many wells throughout the world contain hydrogen sulfide gas (H2S), also known as xe2x80x9csour gasxe2x80x9d. Hydrogen sulfide gas can be harmful to humans or livestock at very low concentrations in the atmosphere. In Alberta, Canada, sour wells commonly produce hydrocarbon fluids with concentrations of 2-4% H2S and often as high as 30-35% H2S. These are among the most sour wells in the world. It is also known that sour gas can cause embrittlement of steel, such as the steel used in drill pipe. This is especially true when drill pipe contains hardened steel, which is commonly used to increase the life of the drill string. Due to a tendency for drill pipe to become embrittled when exposed to H2S and the possibly disastrous effect of sour gas in the atmosphere with its potential for environmental damage or injury to people or animals, it is extremely uncommon to perform drill stem tests on sour wells. Even a pin hole leak in a drill pipe used for such purposes could have deleterious results.
Unfortunately, many highly productive wells are very sour and found in exploratory areas. In some cases, oil companies have been prepared to go to the expense of temporarily completing a sour well by renting production tubing and hanging it in a well without cementing casing in place, just to effect a production test. This method, due to the increase in rig time, can cost in excess of $200,000, which could be greater than the cost of a completion in shallow wells.
Coiled tubing is now known to be useful for a myriad of oilfield exploration, testing and/or production related operations. The use of coiled tubing began more than two decades ago. In the years that have followed coiled tubing has evolved to meet exacting standards of performance and to become a reliable component in the oil and gas service industry. Coiled tubing is typically manufactured from strips of low alloy mild steel with a precision cut, and rolled and seam welded in a range of OD (outside diameter) sizes, envisioned to run up to 6 inches. Currently, OD sizes are available up to approximately 4 inches. Improvements in manufacturing technology have resulted in increased material strength and consistent material quality. Development of a xe2x80x9cstrip bias weldxe2x80x9d has improved the reliability of factory made joints in the coiled tubing string. Heat treatment and material changes have increased resistance of the tubing to H2S induced embrittlement and stress corrosion cracking that can incur in operations in sour environments. An increase in wall thickness and the development of higher strength alloys are also allowing the industry to increase the depth and pressure limits within which the tubing may be run. The introduction of new materials and structure, such as titanium and composite material tubing design, is also expected to further expand coiled tubing""s scope of work.
Coiled tubing could be particularly valuable in sour or very sour wells due to coiled tubing""s typically softer steel composition that is not so susceptible to hydrogen sulfide embrittlement. However, another factor inhibits producing sour gas or performing a DST in a sour well with coiled tubing. The repeated coiling and uncoiling of coiled tubing causes tubing walls, presently made of the steel, to plastically deform. Sooner or later the plastic deformation of the tubing wells is likely to cause a fracture. A resulting small pin hole leak or crack could produce emissions.
Oil and gas operations have known the use of concentric pipe strings. Concentric pipe strings provide two non wellbore channels for fluid communication downhole, typically with one channel, such as the inner channel, used to pump fluid (liquid or gas or multiphase fluid) downhole while a second channel, such as the annular channel formed between the concentric strings, used to return fluid to the surface. (A further annulus created between the outer string and the casing or liner or wellbore could, of course, be used for further fluid communication). Which channel is used for which function can be a matter of design choice. Both concentric pipe channels could be used to pump up or down.
Concentric tubing utilizing coiled tubing, at least in part, has been proposed for use in some recent applications. Coiled tubing enjoys certain inherent advantages over jointed pipe, such as greater speed in running in and out of a well, greater flexibility for running in xe2x80x9clivexe2x80x9d wells and greater safety due to requiring less personnel to be present in high risk areas and the absence of joints and their inherent risk of leaks.
Patterson in U.S. Pat. No. 4,744,420 teaches concentric tubing where the inner tubing member may be coiled tubing. It is inserted into an outer tubing member after that member has been lowered into the wellbore. In Patterson the outer tubing member does not comprise coiled tubing. As FIG. 8 of Patterson illustrates, the inner tubing is secured within the outer tubing by spaced apart spoke-like braces or centralizers which hold the tubing members generally centered and coaxial. Sudol in U.S. Pat. No. 5,033,545 and Canadian Patent No. 1325969 discloses coaxially arranged endless inner and outer tubing strings. Sudol""s coaxial composite can be stored on a truckable spool and run in or pulled out of a well by a tubing injector. Sudol""s disclosure does not explicitly disclose how the coaxial tubing strings are maintained coaxial, but Sudol does show an understanding of the use of centralizers. U.S. Pat. No. 5,086,8422 to Cholet discloses an external pipe column 16 which is inserted into a main pipe column comprising a vertical section and a curved section. An internal pipe column is then lowered into the inside of the external pipe column. Cholet teaches that the pipe columns may be formed to be the rigid tubes screwed together or of continuous elements unwound from the surface. Cholet does not teach a single tubing composite that itself is wound on a spool, the composite itself comprising an inner tubing length and an outer tubing length. All of Cholet""s drawings teach coaxial concentricity. U.S. Pat. No. 5,411,105 to Gray teaches drilling with coiled tubing wherein an inner tubing is attached to the reel shaft and extended through the coiled tubing to the drilling tool. Gas is supplied down the inner tube to permit underbalanced drilling. Gray, like Sudol, discloses coaxial tubing. Further, Gray does not teach a size for the inner tube or whether the inner tube comprises coiled tubing. A natural assumption would be, in Gray""s operation, that the inner tube could comprise a small diameter flexible tube insertable by fluid into coiled tubing while on the spool, like wireline is presently inserted into coiled tubing while on the spool. The Griffiths patent, U.S. Pat. No. 5,503,014, issued Apr. 2, 1996, filed Jul. 29, 1994, practices a version of drill stem testing using dual coaxial coil. No test tool or bottomhole assembly is taught.
The present invention solves the problem of providing a safeguarded method for communicating potentially hazardous fluids and materials through coiled tubing. This safeguarded method is particularly applicable for producing and testing fluids from wells including very sour gas wells. The safeguarded method proposes the use of coiled-in-coiled tubing, comprising an inside coiled tubing length located within an outside coiled tubing length. Potentially hazardous fluid or material is communicated through the inside tubing length. The outside tubing length provides a backup protective layer. The outside tubing defines an annular region between the lengths that can be pressurized and/or monitored for a quick indication of any leak in either of the tubing lengths. Upon detection of a leak, fluid communication can be stopped, a well could be killed or shut in, or other measures could be taken before a fluid impermissibly contaminates its surroundings.
As an additional feature, the annular region between the tubing lengths can be used for circulating fluid down and flushing up the inside tubing, for providing stimulating fluid to a formation, for providing lift fluid to the inside tubing or for providing fluid to inflate packers located on an attached downhole device, etc.
The present invention also relates to the assembly of multicentric coiled-in-coiled tubing, the proposed structure offering a configuration and a method of improved or novel design. This improved or novel design provides advantages of efficient, effective assembly, longevity of use or enhanced longevity with use, and possibly enhanced structural strength. A preferred method and alternate methods of assembly of multicentric and concentric coil-in-coil are disclosed.
It has been discovered that coiled-in-coiled tubing can offer the same benefits of flexibility and thrustability that are found in single coiled tubing when compared to jointed pipe, characteristics particularly useful for work in horizontal and/or deviated wells. However, coiled-in-coiled tubing provides the operator with two conduits as opposed to one for the communication of fluids, as from the surface to the bottomhole, or from the bottomhole to the surface, from the surface to tool combinations in a bottomhole assembly, and/or to provide an insulating chamber. These conduits are in addition, of course, to the tubing-wellbore annulus that can or could be used as a conduit.
Some operations, as discussed above and below, can benefit from the availability of a safeguarded or insulated production conduit. Some tools, as mentioned in the above discussion of Sudol and the sand vacuuming tool, prescribe two fluid conduits for their operation, and others might benefit from such.
Given the construction of prototype coiled-in-coiled tubing, it has been subsequently discovered that well operations such as treating, forming, testing and/or measuring operations and the like, and especially including combinations of the above, could be performed cost effectively on coil-in-coil. For instance, the efficiency of testing combined with well enhancing operations could be increased if performed in the same run downhole with other operations. The flexibility provided by the availability of plural conduits for pumping down, pumping up, and circulating fluids, and performing the same simultaneously or sequentially, makes possible many novel combinations of operations not before possible in a run downhole. Plural circulating conduits permit combinations of operations to be performed downhole in new, improved and novel manners. The added efficiency can justify the added cost of utilizing coil-in-coil, as well as add a safety factor.
This invention relates to the use of coiled-in-coiled tubing (several hundred feet of a smaller diameter inner coiled tube located within a larger diameter outer coiled tube) to provide a safeguarded method for fluid communication. The invention is particularly useful for well production and testing. The apparatus and method are of particular practical importance today for drill stem testing and other testing or production in potentially sour or very sour wells. The invention also relates to an improved xe2x80x9cmulticentricxe2x80x9d coiled-in-coiled tubing design, and its method of assembly.
The use of two coiled tubing strings, one arranged inside the other, doubles the mechanical barriers to the outside environment. Fluid in the annulus between the strings can be monitored for leaks. To aid monitoring, the annular region between the coils can be filled with an inert gas, such as nitrogen, or a fluid such as water, mud or a combination thereof, and pressurized.
In one embodiment a fluid, such as water or an inert gas, can be placed in the annulus between the tubings and pressurized. This annular fluid can be pressurized to a greater pressure than either the pressure of the hazardous fluid being communicated via the innermost string or the pressure of the fluid surrounding the outer string, such as static drilling fluid. Because of this pressure differential, if a pin hole leak or a crack were to develop in either coiled tubing string the fluid in the annulus between the inner and outer string would flow outward through the hole. Instead of sour gas, for instance, potentially leaking out and contaminating the environment, the inner string fluid would be invaded by the annular fluid and continue to be contained in a closed system. An annular pressure gauge at the surface could be used to register a pressure drop in annular fluid, indicating the presence of a leak.
Communicated fluids through the inner string could be left in the closed chamber comprised of the inner string, for one embodiment, or could be separately channeled from the coiled-in-coiled tubing at the spool or working reel. Separately channeled fluids could be measured, or fed into a flare at the surface or produced into a closed container, for other embodiments.
The coiled-in-coiled tubing should be coupled or attached to a device at its distal end to control fluids flowing through the inner tube. Fluid communications through the annular channel should also be controlled. At a minimum this control might comprise simply sealing off the annular region. For drill stem testing, packers and packing off techniques could be used in a similar fashion as with standard drill stem tests. An additional benefit is provided by the invention in that a downhole packer could be inflated with fluid supplied down the coiled-in-coiled tubing.
The inner coiled tube is envisioned to vary in size between xc2xdxe2x80x3 (inches) and 5xc2xdxe2x80x3 (inches) in outside diameter (xe2x80x9cODxe2x80x9d). The outer coiled tube can vary between 1xe2x80x3 and 6xe2x80x3 in outside diameter. A preferred size is 1xc2xc to 1xc2xdxe2x80x3 O.D. for the inner tube and 2xe2x80x3 to 2xe2x85x9cxe2x80x3 O.D. for the outer tube.
It is known that steel of a hardness of less than 22 on the Rockwell C hardness scale is suitable for sour gas uses. Coiled tubing can be commonly produced with a hardness of less than 22, being without the need for the strength required for standard drill pipe. Thus, coiled tubing is particularly fit for sour gas uses, including drill stem testing, as disclosed. Other materials such as titanium, corrosion resistant alloy (CRA) or fiber and resin composite could be used for coiled tubing. Alternately, other metals or elements could be added to coiled tubing during its fabrication to increase its life and/or usefulness.
The invention further includes apparatus and method for use in downhole well operations such as treating, forming, testing or measuring and the like, and especially in combinations of the above. Treating operations refer generally to operations such as acidizing or fracturing or heating or other well stimulating activities, including injecting chemical and biological additives. Specifically, treating might refer to operations such as a polymer squeeze to close off suspected water producing zones, clay swelling control mechanisms, sand control mechanisms, filter cake removal systems, iron or sludge control and fines migration control. Treating might also refer to the addition of one or more of the following, either separately or in combination: emulsifiers, gellants, polymers, surfactants, buffers, neutralizers, corrosion control agents, inhibitors, diverting agents, breakers, cements, fluid loss control additives, detergents, cleaning agents, solvents, sequesterants, suspending agents, gels or proppants, foam or defoamers, gases, friction reducers, retarders, lost circulation material, flushes and preflushes, wax or paraffin removers, asphaltine control agents, viscosifiers, dispersants, bonding agents, cement additives and scale inhibitors. Generally, treating fluids could refer to any combination of acid and/or fracturing fluids as well as to additives thereto. Treating fluids would be mixed and applied simultaneously or sequentially according to the need of the particular formation. Treating operations could include jet cleaning and sand vacuuming operations.
Forming operations include operations such as drilling, modifying, perfing (perforating), establishing build sections and forming dog legs, as well as other activities that affect the structure and conformance of the wellbore.
Testing operations include producing operations, including both production testing and long term production. A general purpose tool might be referred to as a production/test tool.
There could be an overlap between testing tools and measuring tools. Measuring tools include the spectrum of logging tools as well as pressure measuring devices, flow meters, densitometers, locating tools, sampling tools and tools to perform chemical analyses or geological and geophysical analyses downhole.
Apparatus for use in well operations in accordance with the present invention comprises coiled-in-coiled tubing having an inner coiled tubing length contained within an outer coiled tubing length. The two tubing lengths define a first inner coil fluid conduit and a second inter-coil xe2x80x9cannularxe2x80x9d fluid conduit. The apparatus includes a bottomhole assembly package adapted to attach to a portion of the coiled-in-coiled tubing, typically attaching to the distal end of the coiled-in-coiled tubing, and in fluid communication with both fluid conduits defined by the coiled-in-coiled tubing.
The apparatus may include at least one packer adapted to be associated with the bottomhole assembly or the tubing. Typically the packer would be associated with the bottomhole assembly and might comprise a straddle packer. The packer optionally could be structured to permit the tubing to reciprocate or to slide while the packer packs off between a portion of the borehole wall and the tubing.
An emergency packer deflation mechanism might be included in the event of loss of communication. The mechanism could operate by pressure application to a sheer pin or a number of pins or by a variety of other methods, which would allow fluid to escape from the packers to the wellbore or to the coil tubing.
In most applications a surface control mechanism would control fluid communication within both the inner conduit and the coiled-in-coiled annular conduit. Preferably the coiled-in-coiled tubing at the surface would be connected to a spool or reel at its proximate end. The flow from both conduits could be separated with an adapting mechanism at the spool or reel to channel or control each flow separately, as desired.
A bottomhole assembly package could range from the elaborate to the simple. A drillstem test tool as disclosed in FIGS. 5 and 5A comprise one bottomhole assembly package. The tool is designed such that it could function as a production/test tool and a treatment injection tool. Valves in the tool control fluid communication between the inner and the annular conduits and the wellbore as well as between the conduits themselves. Alternately, a bottomhole assembly might comprise one or more of a production/test tool, a pump tool, a treatment injection tool, a vacuum tool, a jetting tool, a perfing tool, a drilling tool, an orienting tool, a hydraulic motor and/or an electric motor. A treatment injecting tool could inject treatment fluid. The bottomhole assembly might include a variable spacing unit. Such units could provide spacing from one to fifty meters.
Presently available tools, such as enumerated in the above list, would likely need to be adapted to work effectively with coiled-in-coiled tubing in a bottomhole assembly package. Some tools, such as a Sudol sand vacuuming tool, or a drillstem test tool as in FIG. 5, is adapted to work with coiled-in-coiled tubing. Adapting other tools to function in a bottomhole assembly package connected to coiled-in-coiled tubing may require only an appropriate sub to connect the tool fluid communication ports with the fluid communication capabilities of the coiled-in-coiled tubing, or with the tool sections above. If multiple tools are packaged in a bottomhole assembly, some provision will likely be made to port the tool""s own fluid communication ports with the fluid communication ports of the above tool as well as to port fluid communication through or around the tool in order to serve tools connected below. Such engineering and design parameters can be worked out as preferred bottomhole assembly packages develop. The greater the commercial market for a particular tool package assembly, the greater the likelihood that fluid communication channels will be incorporated into the tool body self as opposed to being arranged in an ad hoc or temporary fashion.
It is envisioned that pumps associated with a bottomhole assembly may include jet pumps, chamber liftpumps, and/or electric pumps. Such pumps could function as alternate systems to recover well effluent to the surface for measurement or analysis. Electrical submersible pumps are known. A wireline will likely extend through one of the two coiled-in-coiled tubing conduits to establish electrical communication between the surface and the bottomhole assembly package. The electrical communication could serve the functions of both power and communication, as is illustrated and taught in U.S. Pat. No. 4,898,236 to Sask, entitled xe2x80x9cDrill Stem Testing System.xe2x80x9d The important role of real time data is discussed in the Sask patent. The wireline could include a conductor within a braided line. Fibre optic wireline cables are also a possibility. If the wireline is to be included in the coiled-in-coiled annular conduit, as opposed to the inner conduit, the coiled-in-coiled tubing would likely be concentric as opposed to multicentric. Any single or multi-line conductor within a braided line or smaller coil tubing could function as a communication cable.
A variety of measuring tools may fortuitously be included in a bottomhole assembly package. Provision would be advantageously provided for multiple pressure, temperature, logging or other measurements.
The apparatus for use in well operations may omit a packer associated with the tubing and/or bottomhole assembly, as the bottomhole assembly package may include multiple tools and function that have no need for packing off. When a packer is included with the bottomhole assembly, one conduit of the coiled-in-coiled tubing could advantageously be used to hydraulically set the packer. Inflatable/deflatable strata packers may be appropriate for many operations.
The availability of the above apparatus, namely coiled-in-coiled tubing and an appropriate bottomhole assembly package, makes possible the performance of a variety of novel, efficient and cost effective downhole well operations, performable in one run. For such operations, the coiled-in-coiled tubing should be connected to the bottomhole assembly package such that both the inner and the annular fluid conduits are in fluid communication with the assembly.
The bottomhole assembly is to be located down a wellbore. Most easily the assembly is injected down the wellbore attached to the distal end of the coiled-in-coiled tubing being injected from a spool. One advantageous method of use of the above apparatus includes packing off between a portion of the wellbore and a portion of the tubing and/or assembly and pumping fluid down at least one of the two coiled-in-coiled tubing conduits for operations. Fluid, for instance, could be pumped down to set the packer. Fluid pumped down the conduit could also be advantageously used to power tools and to circulate into the wellbore. Wellbore fluid could be produced up a conduit, simultaneously or in sequence with pumping down to facilitate flushing operations.
For example, if a combination production/test and treatment injection tool, such as that of FIGS. 5 and 5A, were to comprise the bottomhole assembly, together with a packer, the methodology could include first setting the packer amid the drilling fluid in a wellbore by using water in a first conduit, preferably the annular conduit. The first conduit could then be shut off and wellbore fluid below the packer produced up the second conduit, preferably the inner conduit. The drilling fluid or mud remains in the wellbore tubing annulus above the packer. In the present example subsequent operation will not contaminate or otherwise destroy the value of this drilling fluid by circulating extraneous materials through it.
If testing of the produced fluid indicates that a well treatment might improve production, valves can be opened that permit circulation between the first conduit and the second conduit. Water in the first conduit and production fluid in the second conduit (and in the wellbore beneath the packer to a certain extent) can be circulated out and a treating fluid, such as acid, pumped down. When the fluids are suitably flushed, the second conduit can be closed and the treating fluid, such as acid, injected into the wellbore below the packer through the first conduit. The treating fluid may be followed by water. Both conduits may then be closed while the chemical acts. Production can be reestablished back up the second conduit, producing first any residual fluids in the conduit, spent acid and then formation fluid.
It can be assumed that the acid injected down the first conduit was followed by water such that when the acidizing is complete, water remains trapped in the first conduit. The formation fluid can be advantageously tested anew. If the test results on the produced formation fluid are now satisfactory, the packer can be deflated, particularly aided by using a conduit to depressurize the packer chamber, and the process repeated at another location. If the test results are unsatisfactory, the flush and treatment cycle can be repeated, using the same or different treatment fluids. Straddle packers can be used in lieu of a single packer to suitably isolate a production zone.
If testing indicates that a zone produces water, a polymer squeeze chemical could be applied through one conduit, such as the first conduit, to wall off the zone from production. The success or effectiveness of the polymer squeeze could be immediately subsequently tested by production with the tool. In the above sequence of operations, the drilling fluid in the well above the packer has not been contaminated by the necessity to flush any fluids through the wellbore-tubing annulus above the packer.
A packer might be set downhole such that it permits coiled-in-coiled tubing to slidingly reciprocate while the packer packs off between the wellbore and the tubing wall. Some treating operations such as sand vacuuming and/or jet cleaning require the movement of a tool during operation. Drilling also depends upon movement of the coiled tubing within the wellbore. A packer permitting the tubing to reciprocate through it, set at a build section, might permit, for instance, a horizontal well to be overbalanced in its vertical section, having drilling fluid above the packer, and underbalanced in its horizontal section below the packer. Gas could be pumped down one of the two conduits with liquid down the other, both to the bit, to drill under variably balanced conditions while providing adequate cooling and lifting power to the bit and at the same time a conduit carrying only liquid for acoustic communication and hydraulic fluid.
In one methodology, with or without a packer, fluid could be pumped down both conduits to a bottomhole assembly where each fluid comprises either a hydraulic operating fluid or a well treatment fluid. This methodology would permit the mixing of chemicals downhole. For instance, a first and second chemical might pump more favorably unmixed, such as fracturing fluid and gel setting chemicals and/or gel breaking chemicals, or such as two different acids. It is sometimes advantageous to have two different treatment fluids that are not mixed until ready for use. Heat could be generated downhole more safely by the mixture there of two chemicals.
Combustion downhole might be controlled by a controlled supply of oxygen. Two different tools could be hydraulically operated, each having their own independent hydraulic pressure and flow rate controlled at surface, as a hydraulically operated bit and a hydraulically operated orienting tool, or a hydraulically operated bit and a hydraulic jetting tool. One conduit could contain hydraulic fluid for operating a rotary cleaning jet while the other conduit contained a fluid, such as an acid fluid, for selectively dispensing out the rotating jets. Hydraulic fluid down one conduit could operate a pump while a treating or jetting fluid could be administered through the other conduit. In one embodiment a rotating jet cleaning tool could be operated together with a sand vacuuming tool. Many such tools could be computer controlled through real time feed back data.
In another methodology the outer conduit could be used to provide thermal insulation for fluid in the inner conduit. For example, viscous oil could be produced through the inner conduit while thermal insulation could be provided by a fluid, such as a gas, air, a gel or other insulation material in the outer conduit. For the purposes of the present disclosure a vacuum should be considered as a xe2x80x9cgasxe2x80x9d fluid, as it represents a limiting condition for the presence of a gas. Such insulating fluid could keep the oil temperature up and thus the oil viscosity down so that the oil could be more readily brought to surface.
One utilization of the present invention includes a methodology in which the bottomhole assembly comprises at least a pair of valved producing/treating tools separated by a bottomhole assembly spacer. Wellbore fluid could be produced from two different locations, each up a different conduit. The embodiment could be operated with or without packers. Advantageously the two producing tools could be separated by a packer in order to test alternative producing zones.
A surface computer system could be advantageously employed to recover and analyze data in real-time in order to calculate reservoir parameters. The same surface computer system could be used to control all downhole tool valves for the movement of all fluids and gases. The apparatus and method advantageously includes capability for remote data transmission from the well site to another location.
The present invention also includes optimal methods for assembling coiled-in-coiled tubing. These methodologies include extending a first length of coiled tubing essentially horizontally. A second inner coiled tubing length could then be pumped through the first coiled tubing length and/or pulled through the first coiled tubing length, by means of a cable, and/or injected through the first coiled tubing length by means of a coiled tubing injector. Any combination of pumping, pulling and injecting, together with lubricating between the coils, could be used simultaneously or sequentially to accomplish the assembling of coiled-in-coiled tubing.

Method and apparatus using coiled-in-coiled tubing


A process instrument having a wafer-style body for mounting between an upstream flanged pipe and a downstream flanged pipe has a flow passage, a transmitter connected to the body, and first and second end plates fixed to the body. The first end plate has a first set of cams for engaging a plurality of threaded fasteners extending between the upstream flanged pipe and the downstream flanged pipe. The second end plate has a second set of cams for engaging the plurality of threaded fasteners such that the first set of cams and the second set of cams center the flow passage with respect to the upstream flanged pipe and the downstream flanged pipe.

The present invention relates generally to fluid processing and, more particularly, to process instruments. Specifically, the invention concerns the alignment of wafer-style devices installed in a flow line.
Process instruments are used in a wide range of fluid handling systems. While the present invention will be described in the context of a flow measurement device, it is to be understood that the invention could be applied to other types of wafer-style process instruments. Flow measurement devices are used to monitor and control the flow rate or quantity of process flow within a conduit and come in many varieties, including positive displacement and magnetic flow meters, suited for use in numerous applications. The different types of meters employ technology based on the system in which they are installed. For example, a magnetic flow meter is advantageous when the use of moving parts within a flow line is not ideal or practical. While the present invention will be described in the context of a magnetic flow meter, it is to be understood that the invention could be applied to other types of flow meters.
Standard flow meters are interposed between upstream and downstream pipes, each pipe having an end flange. In order to secure the device between the pipes, traditional flow meters are equipped with a flange on each end, each flange having a circle of bolt holes that aligns with bolt holes on the end flanges of the pipes. While flow meter flanges ensure the flow passage of the meter is centered with respect to the flow passage of the conduit, flanged flow meters are relatively large and expensive. Moreover, there a number of possible bolt hole patterns in existing flanged pipelines, requiring flanged flow meters to have distinct bolt hole circles. One solution to reduce cost and simplify installation is to remove the flanges from the flow meter body. While flangeless, or wafer-style, flow meters save money and time, without bolt hole circles on the flanges, these meters can suffer from misalignment issues giving rise to local turbulence and inaccurate meter readings.
Current methods of resolving flow meter alignment issues include providing camming devices positioned between the pipe flanges and the flow meter body during the installation process. Such devices take advantage of existing hardware used to bridge the gap between the upstream and downstream pipes. By rotating camming devices with respect to the flow meter body, the bolts are forced to their extreme positions within the bolt holes, thus ensuring the flow passage of the meter is centered with respect to the flow line. Examples of existing alignment devices are disclosed in U.S. Pat. No. 4,345,464 and U.S. Pat. No. 5,632,632. While these devices can be used to center wafer-style flow meters installed in flanged pipelines having a variety of bolt hole patterns, the additional hardware is problematic both from a production and installation standpoint. Not only is the added equipment less cost-effective and more time-consuming than it could be, the additional hardware, such as camming sleeves or rings and the gaskets required to seal the flow meter between the pipe ends, can easily be ineffectively installed or inadvertently discarded.

Self-aligning wafer-style process instrument


An AC power supply apparatus for obtaining sampled data required for the FFT (Fast Fourier Transformation) by an A/D converter. Since a clock pulse train for forming an output voltage (power supply output) is used as sample clock pulses, sampled data associated with exactly one period can be obtained. This eliminates the need for the window processing. This makes it possible to provide a low cost, error-free apparatus.

1. Field of the Invention
The present invention relates to an AC power supply apparatus for supplying a load with an AC power and Fourier transforming a load current to monitor a spectrum and the like, and to a load current measurement method in an AC power supply apparatus.
2. Description of the Prior Art
Recently, with the diversification of load types connected to an AC power supply apparatus, it has been increasingly required to measure harmonic components contained in a load current.
Heretofore, to achieve such measurement, as shown in FIG. 1, a current value detected by a current detection circuit DET is inputted to an FFT (fast Fourier transformation) analyzer FAZ.
Since the prior art FFT analyzer shown in FIG. 1 is provided separately from an AC power supply PS, it has a so-called window processing is required.
The necessity for the window processing will be described with reference to FIGS. 2-4.
As well known, in analyzing an input signal by the FFT analyzer, the input signal is regarded as a periodical signal having a certain frame time so as to determine its Fourier series. The frame time is a value determined by the design of the analyzer, and is not varied with the input signal. For example, when a sinusoidal input signal shown in FIG. (A) is obtained in the frame time, a problem arises in that a Fourier series of a repeated signal as shown in FIG. 2B is determined.
Therefore, a discontinuous point is generated at a point for connecting the beginning and the end of the frame time, and a spectrum including a leakage (a spectrum number of harmonics) in addition to the proper sinusoidal wave spectrum is determined. However, in an exceptional case, when, as shown in FIG. 3A, the period of the sinusoidal wave exactly fits in one frame (the frame time is an integer multiple of the input signal period), or when, as shown in FIG. 3B, the beginning and the end of the signal are considered to converge to a same value, such discontinuous points are not generated and the exact spectrum can be determined.
Then, as a measure for such a problem, it is generally performed that an original signal is multiplied by a function called a window for reducing the leakage to transform the shape of the original input signal into the shape of the signal whose beginning and end converge at zero, thereby eliminating the generation of discontinuity. For example, when the original input signal is as shown in FIG. 4A, the signal multiplied by the window function is as shown in FIG. 4B (see, also FIG. 14A). The FFT analyzer determines a spectrum according to the window processed signal.
As described above, heretofore, in analyzing harmonic components contained in an AC load current, an appropriate window processing has been required to obtain an exact measurement value.

AC power supply apparatus and load current measurement method in AC power supply apparatus


A side view mirror for an automobile is configured to maximize viewing area and minimize image distortion. The side view mirror has a flat portion, having a flat portion major axis, a flat portion minor axis and a convex portion height. A convex portion is smoothly joined to the flat portion and having a convex portion major axis, a convex portion minor axis, a convex portion height; wherein the convex portion is configured to be defined around an origin point.

The embodiments herein relate generally to mirrors on automobiles. The challenge in mirrors on automobiles is to maximize viewing area while minimizing distortion. There is no shortage of endeavors in this regard, including: U.S. Pat. No. 3,408,136 issued to Travis; U.S. Pat. No. 6,069,755 issued to Li; U.S. Pat. No. 3,338,655 issued to Young; Published U.S. Application 2003/0081334 filed by Skinner; U.S. Pat. No. 6,199,993 issued to Mou; U.S. Pat. No. 8,128,244 issued to Lynam; U.S. Pat. No. 8,267,535 issued to Zhao; and U.S. Pat. No. 8,736,940 issued to Rawlings.
Travis and Skinner teach a rear view mirror with flat and convex elements. The convex portion is a rectangular convex shape (that is, a bent rectangle). Young uses a circular convex shape instead of a rectangle. Lynam and Rawlings add reflective portions to this mirror arrangement.
Mou and Zhao teach the familiar arrangement of having a small convex portion within an otherwise flat mirror. The present invention teaches away from this by having the round portion extend past the mirror in a number of places.
Li teaches a convex shape comprising numerous distinctive curved surfaces having a widely varying average curvature. In that regard, Li chooses average over Gaussian curvature as a design constraint.
Embodiments of the disclosed invention use a larger convex portion, defined by a different function, and measured by a different standard of consistency. In this regard, embodiments of the present invention offer an entirely unique way of solving this classical problem.


Several methods are described for assessing an individual's likelihood of developing or exhibiting a multifactorial trait. The methods include determining a plurality of genotypes for the individual at a plurality of biallelic polymorphic loci, using the genotypes to compute a score for the individual, and comparing the score to at least one threshold value.

The DNA that makes up human chromosomes provides the instructions that direct the production of all proteins in the body. These proteins carry out the vital functions of life. Variations in the sequence of DNA encoding a protein produce variations or mutations in the proteins encoded, thus affecting the normal function of cells. Although environment often plays a significant role in disease, variations and/or mutations in the DNA of an individual are directly related to almost all human diseases, including cardiovascular, metabolic and infectious disease, cancer, and autoimmune disorders. Moreover, knowledge of genetics, particularly human genetics, has led to the realization that many diseases result from either complex interactions of several genes or their products. For example, Type I and II diabetes have been linked to multiple genes, each with its own pattern of mutations.
Additionally, knowledge of human genetics has led to a limited understanding of variations between individuals when it comes to drug response—the field of pharmocogenetics. Over half a century ago, adverse drug responses were correlated with amino acid variations in two drug-metabolizing enzymes, plasma cholinesterase and glucose-6-phosphate dehydrogenase. Since then, careful genetic analyses have linked sequence polymorphisms (variations) in over 35 drug metabolism enzymes, 25 drug targets and 5 drug transporters with compromised levels of drug efficacy or safety (Evans and Relling, Science 296:487–91 (1999)). In the clinic, such information is being used to prevent drug toxicity; for example, patients are screened routinely for genetic differences in the thiopurine methyltransferase gene that cause decreased metabolism of 6-mercaptopurine or azathiopurine. Yet only a small percentage of observed drug toxicities have been explained adequately by the set of pharmacogenetic markers validated to date. Even more common than toxicity issues may be cases where drugs demonstrated to be safe and/or efficacious for some individuals have been found to have either insufficient therapeutic efficacy or unanticipated side effects in other individuals.
Because any two humans are 99.9% similar in their genetic makeup, most of the sequence of the DNA of their genomes is identical. However, there are variations in DNA sequence between individuals. For example, there are deletions of many-base stretches of DNA, insertion of stretches of DNA, variations in the number of repetitive DNA elements in coding or non-coding regions, and changes in single nitrogenous base positions in the genome called "single nucleotide polymorphisms" (SNPs). Human DNA sequence variation accounts for a large fraction of observed differences between individuals, including susceptibility or resistance to disease and how an individual will respond to a particular therapeutic or treatment regimen.
Multifactorial traits, or complex traits, are influenced by multiple factors, such as genes, environmental factors, and their interactions. Often, more than one combination of genetic and/or environmental factors will result in the same multifactorial trait, and this complexity makes it difficult to determine who will develop such a trait. Further, the contribution of each factor is typically not identical to the contributions of every other factor. That is, for example, some factors may have a very strong contribution while others may have a very weak contribution. To complicate the biological basis of multifactorial traits even more, the contributions of a factor may be additive, synergistic, or completely independent from the contribution of any other factor. Some complex traits manifest common diseases, such as cardiovascular disease, diabetes, obesity, and high cholesterol. Other complex traits include such phenotypes as the way in which an individual responds to a drug or other medical treatment regimen.
In the recent past, research into the genetic basis for disease has resulted in the development of a few genetic tests for diseases. However, these genetic tests will not be useful for predicting a healthy person's probability of developing a common multifactorial disease. Many argue that genetic testing for common multifactorial traits (e.g. diseases) will not be useful in practice due to the incomplete penetrance and low individual contribution of each gene involved (Holtzman and Marteau, 2000; Vineis et al. 2001). However, these arguments are based in large part on the use of single loci to predict whether or not an individual will exhibit the trait (Beaudet 1999; Evans et al. 2001). What is needed is a reliable approach for determining an individual's risk of developing or exhibiting a multifactorial trait that is based on the individual's genotype at a plurality of loci, each of which are factors in the manifestation of the multifactorial trait.


In an embodiment, a switched capacitor transformer transfers a differential reference voltage at its input ports to its output ports, where a capacitor is switched so that the capacitor is coupled to the input ports during a first portion of a cycle of operation and then coupled to the output ports during a second portion of the cycle of operation, where the first and second portions of the cycle of operation are non-overlapping. Other embodiments are described and claimed.

Integrated circuits often contain analog functional unit blocks (FUB) that require one or more reference voltages. For example, in FIG. 1, die 102 comprises a microprocessor with many sub-blocks, such as, for example, phase-locked loop 116, voltage regulator 118, and interconnect driver 120. Some of these FUBs allow die 102 to communicate with other integrated circuits, such as off-die cache 104 and higher memory hierarchy levels, such as system memory 108 accessed via host bus 110 and chipset 112. The reference voltages provided to these various FUBs are often used to set some circuit property, such as, for example, amplifier bias, PLL frequency, or the output voltage of a voltage regulator. The reference voltage should be stable with respect to low and high frequency noise coupled through the semiconductor substrate of die 102, interconnects, or power supply 114. Otherwise, the performance of various FUBs may be degraded. For example, the output voltage of a voltage regulator may fluctuate if the reference voltage is not stable.
Bandgap circuits have been used to generate local reference voltages. However, a bandgap circuit makes use of an amplifier, which may add an offset as well as high frequency power supply noise to the reference voltage. Bandgap circuits at different locations on a die may not provide identical reference voltages due to variations in offset and noise power. A single bandgap circuit may be used to distribute a reference voltage as a single ended signal to different locations on a die. However, a single ended signal is not tolerant to noise coupled through a power supply or the substrate, for example. As a result, differential signaling is often preferred to single-ended signaling. A receiving FUB may utilize a received differential signal directly, or translate the differential voltage into a single-ended voltage referenced to a local ground or local VCC.
Ideally, common-mode noise in a differential signal may be cancelled by forming the difference of the differential signal to arrive at a single-ended signal. An example of a differencing (or subtracting) circuit is shown in FIG. 2. A differential signal is provided at input ports 202 and 204. Resistors 206 are designed to have the same resistance, and the voltage at output port 208 is referenced to ground 210 and is ideally the difference of the voltages at input ports 202 and 204. Common-mode noise at input ports 202 and 204 is ideally subtracted out. However, in practice there is a matching error in resistors 206, and their resistance (for well resistors, for example) may be temperature and voltage dependent. Furthermore, there may be an offset and high frequency noise coupling due to amplifier 212. A low-pass RC filter may be used to filter out high frequency power noise, but due to large MOS gate leakage in present day process technology, it has become difficult to implement an area efficient RC filter with a time constant larger than about 1 nanosecond. There is consequently a need for a noise tolerant voltage distribution technique for present day process technology.

Analog voltage distribution on a die using switched capacitors


A nonvolatile storage element of a single-layer gate type structure is arranged so that a floating gate is formed of a conductive layer which partly overlaps with a control gate, formed of a diffused layer, and is provided with a barrier layer covering a part of or the whole surface of the floating gate. Nonvolatile storage elements characterized as such are used for redundancy control of defects or change of functions.

The present invention relates to a semiconductor integrated circuit device and, more particularly, to technology which is effectively applied in a semiconductor integrated circuit device including nonvolatile storage elements of a single layer polysilicon gate structure.
An example of a mask ROM (Read Only Memory), in which data are written using a mask, is disclosed in U.S. Pat. No. 4,939,386. Since this type of mask ROM can be fabricated by a poly-Si (polysilicon) one-layer process and is capable of storing one bit in one transistor, it is suitable for achieving larger capacity at lower cost. As mask ROMs are becoming more and more miniaturized, however, thereby increasing packaging density, some type of defect control technique must necessarily be adopted for improving yield. A known technique for controlling defective bits of the mask ROM is disclosed in, for example, ISSCC (International Solid-State Circuit Conference) Dig. Tech. Papers, February 1989, pp. 128-129, 311. In this paper, a redundancy technique using polycrystalline Si fuse is disclosed.
During the course of developing a new and improved technique using EPROM for redundancy control of defects or altering data stored in semiconductor integrated circuit devices having a memory array of mask ROM or the like, the following problems became evident.
An art using an EPROM (Erasable Programmable Read-Only Memory) of a two-layer gate structure for selecting a redundancy circuit is disclosed in Japanese Laid-Open Patent Publication No. 60-83349. The two-layer gate structure mentioned above is such that it is formed by depositing a gate insulating film, a floating gate electrode formed of a first layer of poly-Si film, an insulating film, and a control gate electrode formed of a second layer-of poly-Si film in succession on a semiconductor substrate. In the EPROM, it is required that a predetermined high voltage (around 12V) be applied to the control gate of an EPROM cell for writing information therein. Accordingly, the insulating film must be a thin insulating film having a quality and thickness controlled so as to satisfy required writing/reading characteristics. Therefore, in technology using the EPROM of a two-layer gate structure for the redundancy circuit, it is required that a special fabrication step be added for forming, for example, a highly reliable insulating film to be interposed between the floating gate and the control gate which thereby increases the number of fabrication steps. Known EPROMs of a two-layer gate structure are disclosed, for example, in U.S. Pat. No. 4,918,501 and IEDM (International Electron Device Meeting) Tech. Dig., pp. 631-634, 1985.
Further, a technology using an EPROM of a single-layer polysilicon gate structure is described, for example, in The Transactions of the Institute of Electronics, Information, and Communication Engineers, Vol. 90, No. 47, pp. 51-53, May 21, 1990.
The present inventors have carefully considered data retaining characteristics in connection with the development of their improved EPROM cell (nonvolatile storage element) and, through careful analyses of the relationship between the structure of the element and the data retaining characteristic, they were able to scheme their invention which is directed to a nonvolatile storage element of single-layer gate structure whereby the data retaining characteristic is improved and to a semiconductor integrated circuit device using such storage elements.
An object of the present invention is to provide a semiconductor integrated circuit device comprising nonvolatile storage elements of single-layer gate structure whereby the data retaining characteristics are improved.
Another object of the present invention is to provide a semiconductor integrated circuit device which is easy to fabricate and in which redundancy control of defects, change of functions, and trimming can be reliably achieved.
The above and other objects and novel features of the present invention will be better understood from the following description taken in connection with the accompanying drawings.
A representative aspect of the invention disclosed herein will be briefly described as follows.
A barrier layer is provided for a nonvolatile storage element of single-layer gate structure, which is constructed by arranging a floating gate formed of a conductive layer to partly overlap with a control gate formed of a diffusion layer, such that the barrier layer covers a part or the whole (or entire) surface of the floating gate. Such nonvolatile storage elements are used for redundancy control of defects or change of functions.
By the above described means, radical hydrogen presumed to diffuse from a final passivation film on the surface of the element is captured by the barrier layer, and, accordingly, a collapsing of information charges stored on the floating gate can be prevented. Thereby, with high reliability, redundancy control of defects or change of functions of semiconductor integrated circuit devices can be attained.


Methods and systems for quickly and accurately identifying a coded identification tag imaged by conventional CCTV video monitoring equipment are presented herein. In one aspect, a coded identification tag includes a plurality of dark-colored polygons arranged around a light-colored central background area to maximize contrast between the polygons and the central background area. An array of dark-colored dots is arranged over the light-colored central background area. A light-colored border is located around the plurality of dark-colored polygons. A Coded Identification Tag Monitoring (CITM) system estimates the position and orientation of the coded identification tag with respect to the collected image based on the unique orientation of the coded identification tag with respect to an image frame. In some examples, the CITM system decodes the coded identification tag when the tag occupies less than 10% of the area of the image collected by the video imaging system.

Automated identification of objects based on identification tags is widespread. A wide variety of tags and associated reading systems have been developed to perform an identification task with high accuracy. Examples include bar code identification tags and systems, magnetic identification tags and systems, etc.). However, these high accuracy identification techniques have some disadvantages. First, these identification systems require specialized tools to detect the code. Second, the detection hardware typically requires interaction with the identification tag at close range (e.g., touch magnetic card on a detector surface). Third, the specialized detection tools add cost to an overall identification system.
Closed circuit television (CCTV) systems are typically employed to monitor the presence and movements of people and objects in publically accessible areas. Modern, networked CCTV units record a stream of digital images and upload the recorded images to memory over a digital network. Although CCTV video imagery is available at relatively low cost, robust, high accuracy identification based on CCTV video imagery is currently limited by commonly available image resolution and practical computational limits.
For example, identification for access control requires very high accuracy of identification. This is particularly the case when access control to sensitive sites is required (e.g., access to military installations, high technology facilities, medical facilities, etc.). In some examples, accuracy of identification should be near perfect (e.g., 99.999%). Currently, this is out of reach of computationally practical facial recognition systems based on CCTV imagery.
Improvements to existing identification systems are desired to facilitate the identification of persons or objects of interest within images collected by conventional CCTV monitoring equipment at normal monitoring distances.

Methods and systems for recognizing and reading a coded identification tag from video imagery


Protective clothing and/or equipment may comprise an impact mitigation layer which comprises a plurality of impact mitigation assemblies positioned between an exterior surface and an interior surface. The plurality of impact mitigation assemblies may comprise an impact absorbing array of impact mitigation structures having at least one filament and a lateral support wall or connecting element. When force is applied to the exterior surface, the structures of the impact absorbing materials deform in a desired and controlled manner, reducing the force received by the interior surface.

Impact absorbing structures can be integrated into protective clothing or other structures to desirably prevent and/or reduce the effect of collisions between stationary and/or moving objects. For example, an athletic helmet typically protects a skull and various other anatomical regions of the wearer from collisions with the ground, equipment, other players and/or other stationary and/or moving objects, while body pads and/or other protective clothing seeks to protect other anatomical regions. Helmets are typically designed with the primary goal of preventing traumatic skull fractures and other blunt trauma, while body pads and ballistic armors are primarily designed to cushion blows to other anatomical regions and/or prevent/resist body penetration by high velocity objects such as bullets and/or shell fragments. Some protective clothing designs primarily seek to reduce the effects of blunt trauma associated with impacts, while other designs primarily seek to prevent and/or reduce "sharp force" or penetration trauma, including trauma due to the penetration of objects such as bullets, knives and/or shell fragments into a wearer's body. In many cases, a protective clothing design will seek to protect a wearer from both blunt and sharp force injuries, which often involves balancing of a variety of competing needs including weight, flexibility, breathability, comfort and utility (as well as many other considerations).
For example, a helmet will generally include a hard, rounded shell with cushioning inside the shell (and typically also includes a retention system to maintain the helmet in contact with the wearer's head). When another object collides with the helmet, the rounded shape desirably deflects at least some of the force tangentially, while the hard shell desirably protects against object penetration and/or distributes some amount of the impact forces over a wider area of the head. The impact absorbing structures, which typically contact both the inner surface of the helmet shell and an outer surface of the wearer's head, then transmits this impact force (at varying levels) to the wearer's head, which may involve direct contact between the hard shell and the head for higher impact forces.
A wide variety of impact absorbing structures have been utilized over the millennia, including natural materials such as leathers, animal furs, fabrics and plant fibers. Impact absorbing structures have also commonly incorporated flexible membranes, bladders, balloons, bags, sacks and/or other structures containing air, other gases and/or fluids. In more recent decades, the advent of advanced polymers and foaming technologies has given rise to the use of artificial materials such as polymer foams as preferred cushion materials, with a wide variety of such materials to choose from, including ethyl vinyl acetate (EVA) foam, polyurethane (PU) foam, thermoplastic polyurethane (TPU) foam, lightweight foamed EVA, EVA-bound blends and a variety of proprietary foam blends and/or biodegradable foams, as well as open and/or closed cell configurations thereof.
While polymer foams can be extremely useful as cushioning structures, there are various aspects of polymer foams that can limit their usefulness in many impact-absorption applications. Polymer foams can have open- or closed-cell structures, with their mechanical properties dependent on their structure and the type of polymer of which the cells are made. For open-cell foams, the mechanisms of cell edge and micro-wall deformations are also major contributors to the mechanical properties of the foam, while closed cell mechanical properties are also typically affected by the pressure of gases or other substance(s) present in the cells. Because polymer foams are made up of a solid (polymer) and gas (blowing agent) phase mixed together to form a foam, the dispersion, shape and/or directionality of the resulting foam cells are typically irregular and fairly random, which causes the foam to provide a uniform (i.e., non-directionally dependent) response to multi-axial loading. While useful from a general "cushioning" and global "force absorption" perspective, this uniform response can greatly increase the challenge of "tailoring" a polymer foam to provide a desired response to an impact force coming from different loading directions. Stated in another way, it is often difficult to alter a foam's response in one loading mode (for example, altering the foam's resistance to axial compression) without also significantly altering its response to other loading modes (i.e., the foam's resistance to lateral shear forces).
The uniform, multi-axial response of polymer foams can negatively affect their usefulness in a variety of protective garment applications. For example, some helmet designs incorporating thick foam compression layers have been successful at preventing skull fractures from direct axial impacts, but these thick foam layers have been less than successful in protecting the wearer's anatomy from lateral and/or rotational impacts (and can also allow a significant degree of concussive impacts to occur). While softening the foam layers could render the foam more responsive to lateral and/or rotational impacts, this change could also reduce the compressive response of the foam layer, potentially rendering the helmet unable to protect the wearer from impact induced trauma and/or additional brain concussions.
The balancing of force response needs becomes especially true where the thickness of a given compressive foam layer is limited by the cushioning space available in the protective garment, such as between an inner helmet surface and an outer surface of a wearer's skull. In many applications, it is desirous to minimize helmet size and/or weight, which can require a limited foam layer thickness and/or reduced weight foam layer which may be unable to protect the wearer from various impact induced brain concussions. A concussion can occur when the skull changes velocity rapidly relative to the enclosed brain and cerebrospinal fluid. The resulting collision between the brain and the inner surface of the skull in various helmet designs can result in a brain injury with neurological symptoms such as memory loss. Although the cerebrospinal fluid desirably cushions the brain from small forces, the fluid may not be capable of absorbing all the energy from collisions that arise in sports such as football, hockey, skiing, and biking. Even where the helmet design may include sufficient foam cushioning to dissipate some energy absorbed by the hard shell from being transmitted directly to and injuring the wearer, this cushioning is often insufficient to prevent concussions from very violent collisions or from the cumulative effects of many lower velocity collisions.


Writing predetermined data pattern to an allocated segment of a disk drive and appropriately reading that one data pattern while varying the read focus characteristics provides for efficient and effective read focus optimization in an optical disk drive. In order to produce helpful data, the read focus offset is varied while reading the different segments of the data pattern, thus producing read out signals with different peak to peak amplitudes. This is compared to data which is obtained by reading the same data pattern while the offset is held constant. Optimization of the read focus offset is carried out and made possible by appropriate analysis of the waveforms produced when reading the predetermined data pattern in these two reading passes. By appropriately tracking the results of the various read focus offsets, an optimum read focus offset can be easily determined.

The present invention relates to data storage systems utilizing an optical disk drive. More specifically, the present invention relates to an apparatus and system which optimizes the read focus offset in order to provide optimal focus for a read head in an optical disk drive.
In optical data storage systems, it is necessary to read out data from a data storage media utilizing an optical system. This optical system will detect variations or marks in the data storage media (e.g. an optical disk). These marks are written to the storage media in a meaningful manner and make up the stored data such that accurate retrieval is critical in order to reproduce the stored data.
As expected, the optical system typically includes various lenses and positioning devices which cooperate with one another to provide focusing on the data storage media. The optical characteristics of this system will often change over time thus causing variations in the system operation. These changes can result from a large number of things. Changes in temperature can cause related changes in optical properties, all of which dramatically affect the operation of the system. Further, the optical elements are typically mechanically positioned and aligned. This alignment and positioning can vary as the disk drive itself encounters shock and vibration. All of these misalignments affect the focusing of the read out system, and ultimately affect the performance of the disk drive.
Typically, read out systems include mechanisms which allow some offset to be injected into the focusing control. Often, focusing is controlled by a servo which will drive a focus motor and appropriately position the focusing lens. As is well known, an offset can easily be introduced into this servo system in order to vary the focus operations. Due to the circumstances outlined above, it is necessary to periodically check the focusing operation and insure that optimum focusing parameters are being used.
In addition to variations in the alignment of the focusing system, the actual storage media may not be consistent. Substrate thicknesses in the optical media often change from disk to disk. This requires that the read focus be optimized every time a disk is changed.
While it is possible to optimize the read focus characteristics of the read out system in all appropriate circumstances, lengthy calibration procedures increase the overall spin-up time. As expected, speed is critical in data retrieval systems so a lengthy spin-up time is undesired.
Various methodologies have been used to optimize read focus offset. U.S. Pat. No. 5,574,706 entitled xe2x80x9cFocus Offset Optimization For Reading Optically-Recorded Dataxe2x80x9d describes one such methodology wherein both control marks and reference data marks are recorded in each frame when the disk is initially written. The recorded reference data marks are placed no farther apart than the smallest distance between two successive data marks which must be resolved as a blank space or zero during the read out process. Analyzing the signals produced when reading out these signals, and insuring that the distance between marks can be resolved allows for optimum read focus. This method requires the placement of these reference data marks be recorded in each frame however, thus adding to the complexity of the storage frames. Additionally, a relatively small number of marks are placed in each frame, thus the accuracy of any amplitude measurements is not optimum. Further, high speed focus optimization is not best accomplished using this method.
Further systems have used isolated data sectors which are continually read at different read focus offset levels. This process however is quite time consuming as it requires the same data sector to be read multiple times. Using this methodology, the same data sector is read in order to ensure that variations in media quality and signal characteristics are accounted for. As can be appreciated, however, this process is time consuming. In order to read the same data sector, one complete revolution is required between each reading cycle. Consequently, if samples are to be taken at 30 different focus offset levels, at least 30 revolutions of the disk are required.
It is beneficial to develop a system and process for efficiently optimizing the read focus of an optical storage system. Such an optimum system would be fast, efficient, and would utilize only a small amount of disk space.
The present invention provides a system and method for read focus optimization which is both efficient and accurate. Further, read focus optimization can be accomplished fairly quickly, thus avoiding long spin up time period.
Prior to the actual process of read focus optimization, the data storage media or disk of the present invention is prewritten with three tracks of data specifically configured for the read focus optimization function. These prewritten tracks are placed at or near the middle radius of the disk, as this area is more representative of the user area than other portions of the disk.
The prewritten tracks of data are made up of data patterns which are chosen to simplify the read focus optimization process. The specific patterns are predominantly or exclusively made up of 3T data patterns of the RLL 1, 7 Code. By using this specific pattern, a focus offset can be determined which provides the maximum peak to peak amplitude when the 3T pattern is read out. Alternatively, the specific data pattern could be predominantly or exclusively a 2T pattern, or some other predetermined data pattern, including a combination of the 3T and 2T patterns.
In order to provide realistic conditions, three parallel tracks of data are written at the center radius, with only the center track including the predetermined data pattern. The two adjacent tracks can be written with any data pattern in order to create interference (cross talk) as is typically with user data. When the data is read for purposes of focus optimization however, only the center track is utilized.
In order to determine the optimum read focus, a specially tailored read function is carried out. In this read process, the above referenced center track of pre-recorded data is read out from the storage media in a specific manner. Also, rather than simply decoding this data and providing decoded data to the data buffer, peak to peak amplitude data is provided. The transferred amplitude data is preconditioned over a few channel bit samples in order to reduce the effects of system noise and media defects.
When reading out this predetermined data pattern, variations in the read focus are made. As is well known, the focus motor includes a servo control. Variations in read focus is accomplished by injecting offsets into this servo control at various points throughout the read process. More specifically, the focus offset is varied in a predetermined manner so that predetermined offsets are used in various sectors. In one embodiment of the present invention, the read focus offset starts at a maximum value and is decremented through a predetermined range. This predetermined range is established by factory default settings established by the manufacturer. After all the data is collected, an average 3T amplitude can then be calculated for each data sector.
In order to quickly perform read focus optimization, the read function actually utilizes two separate read passes. In the first pass no variable read focus offset is used. In the second pass, the same track is read while the offset is varied as mentioned above. Based on these two read passes, an amplitude variation can then be determined for each data sector. Specifically, the 3T peak to peak amplitude from the first pass is compared with the 3T peak to peak amplitude from the second pass for each data sector. The data sector with the largest positive difference is determined to have the optimal focus offset, and provides an optimum offset setting for the read focus servo system. This focus offset can then be used when user data is read. This process is efficiently carried out as only two revolutions of the disk are required.
As can be seen from the details outlined above, the system and process of the present invention accomplishes read focus optimization utilizing only three data tracks in the center of the optical disk. Consequently, the remainder of the area is available for user data writing. This provides for efficient use of the data media. Also, the read focus optimization process can be quickly carried out, thus reducing the initialization or spin-up time required for the disk.
It is an object of the present invention to provide a method of optimizing the read focus of an optical storage system which minimizes media consumption. That is, the process does not utilize large amounts of storage media simply for the read focus optimization process.
It is a further object of the present invention to provide a method and system for carrying out read focus optimization which is relatively fast and efficient.
It is a further object of the present invention to utilize a prewritten track of read focus data which includes predetermined data patterns when carrying out read focus optimization.

Read focus optimization for an optical disk drive


Designing a photonics switching system is provided. A photonic switch diode is designed to attain each performance metric in a plurality of performance metrics associated with a photonic switching system based on a weighted value corresponding to each of the plurality of performance metrics. A switch driver circuit is selected from a plurality of switch driver circuits for the photonic switching system. It is determined whether each performance metric associated with the photonic switching system meets or exceeds a threshold value corresponding to each of the plurality of performance metrics based on the designed photonic switch diode and the selected switch driver circuit. In response to determining that each performance metric associated with the photonic switching system meets or exceeds the threshold value corresponding to each of the performance metrics, the photonic switching system is designed using the designed photonic switch diode and the selected switch driver circuit.

1. Field
The disclosure relates generally to an improved silicon photonic chip and more specifically to designing a photonic switching system that utilizes an equalized driver to increase performance of photonic switch diodes located on the silicon photonic chip.
2. Description of the Related Art
Silicon (Si) photonics is a technology that is under worldwide research and development due to its promise of delivering high performance optical components built in low-cost silicon chip technologies. Silicon photonics is the study and application of photonic systems that use silicon as an optical medium. The silicon is patterned with sub-micrometer precision into silicon photonic components. The silicon typically lies on top of a layer of silica in what is known as silicon-on-insulator (SOI).
Photonic switches have been considered as a replacement to electrical switches due to their very large per-port bandwidth enabled by wavelength-division multiplexing, and due to the energy savings provided by the mitigation of optical detection and re-transmission before and after the electrical switch. Photonic switches, which often leverage phase alteration within forward or reverse biased diodes to achieve path selectivity, have demonstrated broad spectral operation with low crosstalk. Designing a photonic switch can be a complex task, requiring tradeoffs of various performance metrics for an optimized design. Notably, speed of the photonic switch is often traded for or against other performance metrics in the design of the photonic switch.

This patent is subject to a terminal disclaimer.

Designing photonic switching systems utilizing equalized drivers

International Business Machines Corporation


An NMR probe having a high-sensitivity solenoid probe coil for receiving free induction decay (FID) signals in nuclear magnetic resonance (NMR) spectroscopy, and an NMR spectrometer which incorporates this probe. The solenoid probe coil is fabricated by a building block approach where it mainly consists of coil substrates having superconducting thin film coils made from superconducting thin film thereon, and side holding plates and a wiring substrate with line pattern of superconducting thin films which are both perpendicular to the coil substrates. The superconducting thin film coils are connected with the line patterns of superconducting thin films by capacitive coupling to make the solenoid coil configuration and solenoid probe coil of superconducting material.

Nuclear magnetic resonance (NMR) spectroscopy, by which one can get atomic level information on matter, is an excellent method of analyzing the structure of a compound. The basic principle of analysis by this method is as follows: a sample placed in a static magnetic field is exposed to a radio frequency magnetic field and a response signal from the excited nuclear spin is received and analyzed. For high resolution analysis, an NMR spectrometer which has a superconducting magnet capable of generating a static magnetic field (B0) is employed. Currently, a 21.6 T (920 MHz) NMR spectrometer is available as an NMR spectrometer which is primarily intended to analyze three-dimensional protein structures.
In protein analysis, the sample volume is very small and the intensity of generated free induction decay (FID) signals is weak. Therefore, a probe for receiving FID signals must be highly sensitive. As described in Patent Document 1 (U.S. Pat. No. 5,247,256 specification), a method which reduces thermal noise by the use of a probe at a low temperature to increase the probe sensitivity has been known. In addition, the use of a superconducting material for the probe coil is also effective in increasing the sensitivity. Surface resistance in superconducting materials is two or more digits lower than that in normal metals such as copper. Therefore, the use of a superconducting material reduces the surface resistance of the probe coil and enables reception of signals with a high sensitivity. An example of the use of a superconducting probe coil is described in Patent Document 2 (U.S. Pat. No. 5,585,723 specification).
Superconductor used for the probe coil is a thin film made on a planar substrate and the film surface is arranged parallel to a static magnetic field in order to prevent deterioration in static magnetic field uniformity due to the perfect diamagnetism of the superconductor. In a typical NMR spectrometer, a static magnetic field is generated vertically (vertical type NMR spectrometer). A sample tube containing sample is inserted vertically and a substrate with superconducting thin film is disposed in a way to surround the sample tube. Hence, the superconductor-based probe coils in the prior art are of the Helmholtz type, saddle type or bird cage type. A probe coil of the bird cage type is illustrated in Patent Document 3 (Japanese Patent No. 3066359 specification). On the other hand, an NMR spectrometer (horizontal type NMR spectrometer) which generates a static magnetic field horizontally can use a solenoid probe coil. Solenoid probe coils are higher in filling factor than Helmholtz type, saddle type or bird cage type probe coils and thus higher in sensitivity.