A process for placing a roller burnished finish on the central portion of an unfinished lathe-turned heater tube includes controlling the rotational speed of the burnishing rollers and the pressure of the burnishing rollers against the central portion of the heater tube so that tooling marks are no longer apparent under substantially 10× magnification and the length of the central portion of the heater tube increases by no more than 0.002 inches per inch of length of the central portion of the heater tube.

In the early 1970s, the American Society for Testing and Materials™ (ASTM) promulgated ASTM D3241 Standard Test Method for Thermal Oxidation Stability of Aviation Turbine Fuels Procedure. This published ASTM standard, most recently revised in 2004, is incorporated herein by reference. The test described in ASTM D3241 measures the thermal stability of jet fuel by subjecting it to test conditions simulating those occurring in jet engine fuel systems.
The ASTM D3241 standard describes the use of an apparatus that, over a period of 2.5 hours, pumps 450 mL of pressurized jet fuel at a fixed volumetric flow rate around and over a single-use long, thin, cylindrical, heated aluminum tube. Such single-use tubes are typically referred to as heater tubes. The color and other characteristics of any fuel oxidation products (i.e., deposits) left on the surface of the central portion of the heater tube, are then evaluated to assess the thermal stability of the jet fuel being tested.
The quality of the surface finish of the single-use heater tube used in the ASTM D3241 test is key to obtaining satisfactory test results. U.S. Pat. No. 3,670,561 ("the '561 patent"), issued Jun. 20, 1972, to Alf Hundere, and which is incorporated herein by reference, illustrates a typical heater tube.
The heater tube used to test jet fuels has a generally circular cross-sectional shape, a substantially constant internal diameter, and an outside diameter that is larger at its extremities than at its central portion. The '561 patent suggests that the heater tube be constructed of aluminum, to minimize manufacturing cost. The outer diameter of the central portion of the tube may be as small as ⅛th of an inch. Furthermore, the '561 patent indicates that the heater tube should have a highly polished surface finish that is consistent from tube to tube and is suitable for rating the level of fuel deposited thereon during a test. U.S. Pat. No. 5,101,658 ("the '658 patent") and U.S. Pat. No. 5,337,599 ("the '599 patent") similarly depict and describe a heater tube and are also incorporated herein by reference.
A paper entitled "Comparison of JFTOT Heater Tube Deposit Rating Methods for the Evaluation of Fuel Thermal Stability," by Robert Morris, et al. of the Naval Research Laboratory, published Dec. 29, 1987, discloses that a standard heater tube can be manufactured from a common aluminum alloy known as 6061-T6 aluminum. 6061-T6 aluminum is an extremely popular alloy because of its low cost, good formability, corrosion resistance, high strength, and attractive appearance.
Disposable heater tubes for testing the thermal stability of fuels have been in existence for more than 30 years. A typical finished heater tube is approximately 6⅜ inches in length, including an approximately 2⅜ inch central portion. The central portion of the heater tube has an outer diameter of approximately ⅛ inch. The remainder of the heater tube has an outer diameter of approximately 3/16 inch.
While the ASTM D3241 standard and the '561, '658, and '599 patents disclose various aspects of the heater tube and the need for a consistent, "highly polished" surface finish, these references do not describe a means, a method, or a best process for obtaining the consistent "highly polished" surface finish. A SAE Technical Paper presented at the Aerospace Technology Conference & Exposition at Long Beach, Calif., between Oct. 14 and 17, 1985, by G. Datschefski and T. G. R. Farthing, entitled "Evaluation of JFTOT Tube Deposits by Carbon Burnoff" indicates that the industry's standard method of creating the surface finish on heather tubes is by the use of a petroleum distillate-based metal polishing liquid containing ammonia.
A metal polishing liquid typically includes an abrasive material suspended in wet lapping. The abrasive material in the metal polishing liquid cuts tiny grooves into the surface of the workpiece being polished. Because these tiny grooves are so small, when a metal polishing liquid is used on a heater tube, the surface of the heater tube appears to the human eye as being bright, reflective, and shiny. Interestingly, the more numerous these tiny grooves, the brighter, shinier and more reflective the surface finish of the heater tube is to the human eye. However, brightness, shininess and reflectivity does not equate to a good surface finish for a heater tube that is used in a jet fuel stability test.
The ASTM D3241 standard test method calls for a visual inspection of the heater tube prior to use. Such visual inspection typically includes checking the surface finish for quality defects and other inconsistencies under a magnifier.
It has long been desired to produce a heater tube with a surface finish superior to that which could be obtained by conventional polishing techniques. Such a heater tube having a superior surface finish would permit advances in studies to understand the mechanism of jet fuel deposit formation on the surface of the central portion of aluminum heater tubes. Use of a heater tube with a superior surface finish would result in a reduction in light scattering from the surface of the heater tube. The reduction in light scattering would permit improved visual observation and study of fuel deposits and their resultant fuel-related effects by reducing the glare associated with heater tubes whose surface finish has been created by the use of abrasive liquid polishing techniques. A heater tube with a superior surface finish would also permit advances in prior art deposit measurement techniques and the development or successful application of new deposit measurement protocols and techniques such as ellipsometry.
One of the techniques that has been evaluated for obtaining a superior surface finish on the central portion of a heater tube is roller burnishing. While roller burnishing has long been practiced as a way of achieving an improved visually pleasing finish on the surface of different items, to include cylindrical workpieces made from aluminum, prior art roller burnishing techniques failed when applied to heater tubes. Specifically, prior art roller burnishing techniques did not produce consistent, high quality surface finishes. For example, in the instruction manual for the CX-1T External Roller Burnishing Machine (copyright 1992), Cogsdill Tool Products, Inc. of Lugoff, S.C., it is indicated that the smaller the workpiece, the greater the speed needed for the roller burnishing tool to obtain a satisfactory surface finish. When this prior art technique of increasing the speed of the roller burnishing tool was tried on aluminum heater tubes, unsatisfactory surface finish results were obtained. Not only is the prior art incorrect with regard to the speed of the roller burnishing tool, but the prior art on roller burnishing also does not provide any instruction concerning the force to be placed on the surface of the heater tube by the burnishing rollers. Nor does the prior art provide any instruction as to understanding when the surface of the workpiece is to be considered as being roller burnished to an acceptable surface finish.
Therefore, there remains a need in the art for a roller burnishing method that will burnish the surface finish of a heater tube.

Method for roller burnishing a heater tube


Method and system for automatically adjusting a hearing aid. The method includes measuring an acoustic reflectance associated with an ear canal as a function of an incident pressure and an acoustic frequency, processing information associated with the measured acoustic reflectance, determining a reflectance slope based on, at least, information associated with the measured acoustic reflectance, and adjusting, at least, one parameter associated with the hearing aid based on, at least, information associated with the reflectance slope. The reflectance slope is associated with a reflectance component varying with the incident pressure.

The present invention relates generally to acoustic devices. More specifically, the invention provides a method and system for automatically adjusting acoustic devices based on acoustic reflectance. For example, the acoustic reflectance is a relationship between reflected waves and incident waves. Merely by way of example, the invention has been applied to hearing aids, but it would be recognized that the invention has a much broader range of applicability.
Hearing aids have been widely used to compensate hearing losses of human ears. A human ear is comprised of an outer ear, a middle ear, and an inner ear. The outer ear includes an ear canal, the middle ear includes an eardrum, and the inner ear includes a cochlea. Depending on individual needs, people often use different types of hearing aids. The types of hearing aids include in-ear aids, behind-ear aids, and canal aids.
These hearing aids are usually fitted to individual ears. Such fitting process includes several steps—measuring extent of hearing loss, determining gain of hearing aid, and adjusting frequency response of hearing aid. These steps are often performed by an audiologist, whose time spent on the fitting process is a significant cost associated with hearing aids. If the fitting process is not successful, the hearing aids are often returned to the manufacturers for full refunds. For example, the return rate may range from about 18% to 28%. Such high return rate can significantly increase costs of hearing aids.
Hence it is desirable to improve techniques for fitting hearing aids.

System and method for automatically adjusting hearing aid based on acoustic reflectance


A system for charging an electric vehicle includes a vehicle-side transformer part arranged behind a license plate of the vehicle. The vehicle-side transformer part couples with a charging station-side transformer part through the license plate when the charging station-side transformer part is arranged in front of the license plate such that electrical energy can be transferred through the transformer parts to the vehicle.

DE 24 34 890 B1 describes such a transmission system having two transformer parts provided respectively on an electric vehicle and a parking space. Electrical energy can be transferred through an inductive path from an AC network at the parking space to the traction battery of the vehicle upon the transformer parts being coupled together. The transformer part of the vehicle is located in a front bumper of the vehicle. The transformer part of the parking space is in a horizontal charging board at the parking space. The transformer parts are mounted on springs to achieve coupling without an air gap therebetween.
DE 24 34 890 B1 assumes that the shape, dimensions, and spatial arrangement of the two transformer parts respectively on the vehicle and the parking space match one another. This is not simple to satisfy in practical environments especially when the transmission system is to be used with vehicles having various diverse designs. The transformer part on the vehicle has to be adequately oriented with respect to the assembly of the transformer part of the parking space. The coupling of the transformer part of the parking space to the transformer part in the front bumper region of the vehicle is made more difficult in modern vehicles as the bumper is usually covered by body trim, such as by the so-called front apron. Moreover, different types of vehicles have various diverse shaped vehicle bodies. This makes a precise alignment of the two transformer parts even more difficult.

Charging system for vehicles where the charging coils are coupled through the vehicle license plate


A method for increasing the recovery of oil from a subterranean formation having at least one producer wellbore drilled therein, whereby a generally horizontal and generally circular wellbore is drilled so that oil is located between the generally horizontal and generally circular wellbore and the at least one producer wellbore. Fluid is injected through the generally horizontal and generally circular wellbore into the formation so that oil is swept to the at least one producer wellbore for recovery through the at least one producer wellbore.

1. Field of the Invention
The invention relates generally to the recovery of hydrocarbon reserves from a subterranean formation and, more particularly, to using a horizontal circular wellbore to improve the recovery of oil from a plurality of producer wellbores drilled into a subterranean formation.
2. Brief Description of Prior Art
In the production of oil from subterranean formations, the oil may be produced initially by allowing the oil to flow, as a result of the oil-bearing formation's natural pressure, to the surface through wellbores extending from the surface into the subterranean oil-bearing formation, without the use of pumps or the like. After the formation pressure has dropped to a value less than that required to cause fluids to flow to the surface at a satisfactory rate, pumps, gas lifts, and other devices are used to move fluids from the formation to the surface. This phase of production, which is referred to as primary production, is often practiced with wellbores drilled in a "nine-spot" pattern 10 as shown in the plan view of FIG. 1, depicting the prior art. The "nine-spot" pattern 10 includes an array of eight producer wellbores 12, 14, 16, 18, 22, 24, 26, and 28 drilled into a subterranean formation (not shown in FIG. 1) to a form a perimeter of wellbores which surround a central wellbore 20. The arrows 30 indicate the direction of flow of oil from the formation into the wellbores during primary production.
After the oil flow from the formation has become insufficient to justify continued primary production using devices such as pumps and gas lifts to remove fluids from the formation directly, the primary production is discontinued and enhanced oil recovery processes are used. Enhanced recovery of the oil can be achieved by a variety of techniques which will vary widely depending upon the particular formation of interest. Three such techniques commonly used are water flooding, gas flooding, and combinations of water and gas flooding, referred to as "WAG" flooding.
In water flooding, water, such as brine or filtered seawater, is injected as a wave of fluid into the oil-bearing formation and pushed from a water injection wellbore toward an oil production well. In the nine-spot pattern 10, shown in FIG. 2, water is injected through the central wellbore 20 into the formation and pushed outwardly in the direction of the arrows 32 toward the perimeter wellbores 12, 14, 16, 18, 24, 26, and 28. Initially, oil and, subsequently, oil and injected water, are recovered from the production wells. Additional quantities of oil can be recovered from many formations by water flooding.
Gas flooding has also been used alone or in combination with water flooding to recover additional quantities of oil from formations. The gas typically comprises an oil miscible solvent such as hydrocarbons containing from one to about five carbon atoms, carbon dioxide, nitrogen, and mixtures thereof and is injected from an injection wellbore across the depth of the oil-bearing formation to form an injection wave of gas passing through the oil-bearing formation toward a production well. The gas may be single contact or multi-contact miscible with the oil, as well known to those skilled in the art. In the nine-spot pattern 10, shown in FIG. 2, gas is injected through the central wellbore 20 into the formation and pushed outwardly in the direction of the arrows 32 toward the perimeter wellbores 12, 14, 16, 22, 24, 26, and 28.
FIG. 3, an elevation view of the nine-spot pattern 10 taken along the line3--3 of FIG. 2, shows the flow patterns of the foregoing water flooding and as flooding. In FIG. 3, the oil-bearing formation is designated by the reference numeral 40, and includes an overburden 42, which formation and overburden are shown penetrated by the central wellbore 20 and the perimeter wellbores 18 and 22. In operation, water is injected via the wellbore 20 into the formation 40 and, because water is heavier than oil, the water tends to "slump" in the formation, particularly if the formation is thick and highly permeable with good vertical communication. As a result, the water flows downwardly and outwardly through a flow path 44 in the formation 40 toward the perimeter wellbores 18 and 22. Gas can be alternated with water in a WAG process and injected via the wellbore 20 into the formation 40 and, because the gas is generally lighter than the water and the oil in the formation, the gas tends to rise in the formation, particularly if the formation has good vertical communication. As a result, the gas flows upwardly and outwardly through a flow path 46 in the formation 40 toward the perimeter wellbores 18 and 22. Oil in the flow paths 44 and 46 will be swept into the perimeter wellbores 18 and 22, but maximum oil recovery from the formation 40 is not achieved.
Because the flow path 44 of water is downwardly, and the flow path 46 of gas is upwardly, a region 50 is formed between the flow paths 44 and 46 adjacent to the perimeter wellbores 18 and 22, as well as each of the other perimeter wellbores 12, 14, 16, 24, 26, and 28, and other areas of the formation, through which little or no injected water or injected gas flows. It can be appreciated that, as a result, a drawback with the foregoing water flooding and gas flooding techniques is that additional oil is not recovered in the regions 50. Additionally, a sub-optimal water sweep occurs in the upper flow path 46 and a sub-optimal gas sweep occurs in the lower flow path 44, which leaves recoverable oil in these areas also.
A further drawback with the prior art is that relatively high pressure must be used to inject water and gas from the injector wellbore 20 into the formation 40 so that, as the water and gas disperse toward each of the perimeter wellbores, the pressure will not be dissipated below the pressure necessary to sweep oil to each of the perimeter wellbores.
Therefore, what is needed is a method and system for recovering oil in the flow paths 44 and 46 and in the region 50 which is not fully recovered by conventional water flooding, gas flooding, or WAG processes.

Using a horizontal circular wellbore to improve oil recovery


An exemplary WDM coupling device may include optical fibers. The coupling device may also include region(s) having varying coefficients of thermal expansion. During a temperature variation, one or more of the region(s) may alter in size to substantially cancel temperature-dependent changes associated with the WDM coupling device.

Wavelength Division Multiplexing (WDM) has revolutionized the world of fiber optics by dramatically increasing the bandwidth of optical fiber. WDM enables a number of different wavelengths of light to be transmitted along an optical fiber, thus increasing the number of light signals that may be transmitted at the same time. For example, an ordinary, non-WDM system may only utilize light signals at a single wavelength, such as 700 nm. In contrast, a WDM system may utilize light signals at a variety of different wavelengths, such as 980 nm, 1330 nm, 1480 nm, 1530 nm, 1560 nm and 1650 nm. Thus, WDM systems can enable multiple light signals at different wavelengths to travel separately and simultaneously along an optical fiber.
Additionally, WDM systems often use WDM couplers to separate light signals traveling at different wavelengths along an optical fiber. This is often done at receiving ends of telecommunications systems, where light signals may be separated and channeled along different fibers to various destinations. For example, if an optical fiber carrying two light signals at different wavelengths is passed through a WDM coupler, the light signals may be separated and exit the coupler along two separate optical fibers. This separation may occur due to the fibers' indices of refraction as well as the orientation and location of the fibers with respect to each other. Thus, a WDM coupler may enable multiple light signals that are multiplexed together to be split, allowing a light signal traveling along one fiber to pass uninterrupted to another fiber.
In addition, a properly calibrated WDM coupler may be used to measure the wavelength of a light signal based on the coupler's inherent wavelength dependence. For example, suppose a WDM coupler is designed to send 50% of a 1530 nm wavelength light signal into a first fiber and 50% of the light signal into a second fiber, and the coupler has different splitting ratios for light signals at other wavelengths. Since the wavelength dependent splitting ratio of the coupler is known at 1530 nm, the coupler could be used to test if an incoming light signal has a 1530 nm mean wavelength. Generally, WDM couplers may be used to measure the wavelength of a light signal in applications such as fiber optic gyroscopes, where the wavelength of light exiting a fiber optic coil may be measured to see what deviations have been caused by the coil. These deviations may then be used to correct the output of the gyroscope by compensating for any variation in scale factor caused by a mean wavelength shift.
Unfortunately, however, existing embodiments of WDM couplers have certain limitations. For example, temperature variations can often alter the intrinsic characteristics of a WDM coupler. To illustrate, a temperature variation within a coupler may cause certain materials to expand or contract, which may result in a change in the length of the optical fibers within the coupler. Additionally, the temperature variation may also change the intrinsic effective index of refraction of the optical fibers. Both of these changes may shift the center wavelength in the coupler's splitting spectrum, thus changing its wavelength-dependent splitting ratio.
Therefore, existing WDM couplers may be vulnerable to temperature variations that degrade the performance of the WDM system. Accordingly, it is desirable to have a coupling device that overcomes the above deficiencies associated with the prior art.

Wavelength division multiplexing coupling device


The present invention relates to power tongs used in the oil and gas industry to make up and break apart the joints on drill pipe and other tubular members. The invention provides a selectively releasable braking apparatus for a power tong. The selectively releasable braking apparatus comprises a braking ring operatively connected to a cage plate of the power tong and a braking surface mechanically connected to the cage plate. The apparatus further has a gripping device capable of selectively gripping and holding the braking surface and has a gear train transferring torque from said brake ring to said braking surface. Power tongs also typically have a throat, a ring gear with an opening, and a cage plate with an opening. The present invention further provides an apparatus for aligning the openings in the ring gear and the cage plate with the throat of the power tong and remotely reversing the direction of rotation of the ring gear and cage plate. The apparatus comprises a stop device preventing relative rotation of the ring gear and the cage plate until a preselected torque load is placed on said stop device. The apparatus also has a selectively releasable cage plate brake and a cage plate latch selectively preventing rotation of the cage plate.

Power tongs have been in existence for many years and are generally employed in the oil and gas industry to grip and rotate tubular members, such as drill pipe. It is necessary to grip drill pipe with high compressive forces while applying a high degree of torque in order to break apart or tighten threaded pipe connections. An example of a conventional power tong can be seen in U.S. Pat. No. 4,084,453 to Eckel. Most current power tong designs such as Eckel include an open slot or throat, through which the drill pipe is passed in order to place the power tong in position around the pipe. Typically power tong designs employ a cam mechanism for converting a portion of the torque into a gripping (compressive) force normal to the pipe. This conversion is often accomplished utilizing a power-driven ring gear having an interior cam surface. The ring gear will also have an opening corresponding in size to the throat of the power tong. The ring gear is rotatively positioned between an upper and a lower cage plate which form a jaw carrier. The cage plates are also rotatively positioned in the power tongs and also have openings corresponding with the throat of the power tong. Multiple jaw members are typically secured between the upper and lower cage plates in such a manner that relative movement between the ring gear and cage plates causes the jaws to ride upon the cam surfaces and to close on the drill pipe. After the jaws have closed on the drill pipe, the cage plates and the ring gear will then rotate as a unit to apply torque to the drill pipe.
In order to initially hold the cages plates stationary while the ring gear rotates sufficiently to close the jaws, a brake band typically encircles the upper cage plate. The brake band applies an initial frictional force to the cage plate, holding the cage plates stationary and allowing the ring gear to move relative to the cage plates. Generally, the brake band is adjustable such that it may be tightened or loosened in order to vary the amount of frictional force applied to the cage plate. After relative rotation begins and the jaws mount the cam surfaces and close on the drill pipe, the jaws will begin to transfer torque to the cage plates which will eventually overcome the resisting frictional force of the brake band. Because the cam surfaces translate torque into radial force, a higher torque needed to overcome the resistance of the brake band will result in a higher radial force being placed on the drill pipe. Therefore the frictional resistance of the brake band may be adjusted to regulate the radial load placed on the drill pipe.
While the prior art brake band has accomplished its intended function, it is very inefficient. After the cage plates and ring gear begin moving as a unit to rotate the drill pipe, the friction caused by the brake band now provides undesirable resistance to the torque being applied to the drill pipe and the energy expended by the power tongs in overcoming this resistance is wasted. Also, since it is primarily the resistance of the brake band which determines the radial force with which the jaws grip the drill pipe, this force cannot be varied without stopping work to adjust the brake band. Furthermore, it is difficult to insure the brake band will provide a constant resisting force to the cage plate. For example, grease or a similar substance may be deposited between the cage plate and brake band thereby lowering the frictional resistance of the brake band. Additionally, brake bands wear over time and do not grip as tightly as originally designed. This wearing tendency is often caused by the fact that the cage plate does not present a continuous surface but has an opening corresponding to the throat of the power tong. The contact of this opening with the brake band during rotation of the cage plate causes excessive wear and damage to the brake band.
After the desired torque has been applied to a drill pipe joint, the direction of the ring gear's rotation is reversed to allow the jaws to back off of the cam surfaces and release the pipe. Again the brake band holds the cage plate stationary during the ring gear's initial reverse rotation. Once the jaws have backed off the cam surfaces, it is necessary for the ring gear and cage plates to move in unison to align the openings of the cage plates and the ring gear with the throat of the power tongs. This is accomplished by the interaction of a backing lug on the ring gear and a backing pin inserted into the upper cage plate. The upper cage plate will have two apertures for receiving the backing pin. The backing pin is inserted into one of the two apertures depending on which direction the ring gear will be applying torque to the drill pipe. The ring gear will rotate relative to the cage plates until the backing pin contacts the backing lug. At this point, the openings of the ring gear and cage plates will be aligned and the interaction of the backing pin and backing lug will cause the ring gear and cage plates to rotate together. The operator of the power tong continues to rotate the ring gear in order to observe when the openings of the ring gear and cage plates are aligned with the throat of the power tongs. This alignment is necessary to back the power tongs off of the drill pipe.
This leads to another disadvantage encountered in prior art power tongs when the tong operator desires to reverse the rotational direction of the power tong. To do so, the operator must manually switch the backing pin to the alternate aperture. This may be very difficult in certain drilling operation, such as when operations are being carried out by an automated pipe handling system and the operator controlling the power tong is working from a control station some distance from the tong. The remote controlling of power tongs presents another problem in that the operator may not be able to view the throat of the power tong from his location. Thus the operator is not able to visually align the openings of the ring gear and cage plates with the power tong's throat in order to back the power tong off of a drill pipe.


A flame retardant aromatic polycarbonate resin composition comprising:    (A) an aromatic polycarbonate resin (component A);    (B) an acrylonitrile-styrene copolymer (component B);    (C) inorganic fillers (components C);    (D) an organic phosphorus compound-based flame retardant (component D); and    (E) a fluorine-containing anti-dripping agent (component E),            the amounts of the above components are specific and particularly the components C consist of (C1) mica and (C2) talc and/or wollastonite in a specific ratio,            and a molded article formed from the resin composition.

1. Field of the Invention
The present invention relates to a flame retardant aromatic polycarbonate resin composition. More specifically, it relates to a resin composition which comprises (i) resin components including an aromatic polycarbonate resin as the main resin component and a small amount of an acrylonitrile-styrene copolymer, (ii) inorganic fillers including mica having a predetermined particle diameter (C-1) and talc and/or wollastonite (C-2), (iii) an organic phosphorus compound as a flame retardant and (iv) a fluorine-containing compound as a anti-dripping agent, provides (a) a molded article having high stiffness, strength and dimensional accuracy, has (b) satisfactory flame retardancy in spite of a relatively small amount of the flame retardant, and (c) rarely wears away a mold though the inorganic fillers are contained. The resin composition of the present invention is suitable for molding parts which need flame retardancy and high dimensional accuracy, such as chassis and frames.
2. Description of Prior Art
High stiffness, strength and dimensional accuracy (low anisotropy) and excellent flame retardancy are required for plastic materials for use in the chassis or frames (may be simply referred to as "optical unit chassis" hereinafter) of apparatuses having an optical unit, such as laser beam printers, copying machines and projectors. A large number of proposals have already been made for the plastic materials for chassis. Low anisotropy is still strongly required for optical unit chassis. The above various apparatuses having an optical unit have been manufactured for a long time and a lot of know-how has already been accumulated. In the field of the apparatuses having an optical unit under the above situation, new models having higher performance have been developed whereas general-purpose models have been improved, placing stress on a reduction in cost. In this case, plastic materials may have problems with cost required for their molds and the service lives of the molds. That is, a material which rarely wears away a mold (to be referred to as "low mold wearability" hereinafter) is sought for.
A large number of resin compositions suitable for use as molded parts such as chassis and frames have been proposed up till now. (i) JP-A 5-287185 (the term "JP-A" as used herein means an "unexamined published Japanese patent application") discloses a resin composition prepared by loading an aromatic polycarbonate resin having a specific molecular weight with a large amount of a glass fiber or the like. And, (ii) JP-A 6-207089 discloses a resin composition which comprises an aromatic polycarbonate resin having a specific molecular weight, a fiber having a non-circular section and a lamellar inorganic filler and achieves low warpage. Further, (iii) JP-A 9-12733 discloses an optical write unit fixing chassis formed from a resin composition which comprises an aromatic polycarbonate resin and mica having a specific particle diameter and a specific thickness. The invention disclosed by JP-A 9-12733 has high stiffness, low warpage and torsion based on low anisotropy, and excellent flame retardancy. That is, it has favorable characteristic properties required for optical unit chassis. However, it is hardly said that molded articles which satisfy all the requirements such as high stiffness, high strength, low anisotropy (high dimensional accuracy), flame retardancy and low mold wearability are obtained from the composition of this invention.
JP-A 1-185360 discloses a resin composition which comprises an aromatic polycarbonate, polycaprolactone and carbon fiber and teaches that the composition has reduced mold wearability. However, the invention disclosed by the above publication does not take into full consideration low anisotropy and fails to disclose technical information on how sufficiently high strength is retained after low anisotropy is achieved.
JP-A 8-115589 discloses a CD-ROM part which comprises a polycarbonate resin, flaky inorganic filler and phosphate compound having a specific structure. However, it is hardly said that the publication discloses a resin composition which satisfies all the requirements such as high stiffness, high strength, excellent flame retardancy and low mold wearability.
JP-A 2001-164105 discloses a resin composition which comprises an aromatic polycarbonate resin, flame retardant, inorganic filler which consists of a glass fiber and talc in a specific ratio and polytetrafluoroethylene having fibril forming capability and teaches that the composition has high stiffness, strength and dimensional accuracy and excellent flame retardancy. However, the composition has room for further improvement as a material for use in models with greater importance attached to a cost reduction.

Flame retardant aromatic polycarbonate resin composition

Abstract: According to the present invention, there are provided a resin composition which has excellent mechanical properties, flame retardancy and dimensional stability, is light in weight and rarely wears away a mold and a molded article of the resin composition.


Installation including an industrial glass furnace (1) including a tank (2) for molten glass (3), a combustion heating chamber (4) situated above the tank (2), and a duct for evacuation of flue gases in communication with said heating chamber (4), and a stone furnace including a firing zone (21) for stone to be fired, the flue gas evacuation duct including a flue gas outlet that is connected to the firing zone (21) of stone to be fired and supplying the firing zone (21) of stone to be fired with flue gases at high temperature.

The furnace is subjected to very high thermal and mechanical stresses. The furnace is constructed with refractory linings of high quality. These refractory linings are costly and sensitive to certain constituents of the glass that are liable to react chemically. The refractory linings being poor conductors of heat, the glass bath is heated from above.
One or more liquid or gas fuel flame burners is or are disposed between the glass bath and the top of the furnace, also referred to as the vault. The glass bath is essentially heated by radiation. The gas outlet temperature is from 1300 to 1600° C. depending on the glass family.
Moreover, the manufacture of glass gives off large quantities of gas. The glass bath is degassed for several hours to prevent the formation of bubbles in the glass. To facilitate the degassing fining additives such as sulfates may be used. The furnace produces batches of glass of chosen composition.
The flue gases, from degassing and from combustion, are evacuated via a chimney.
Attempts have been made to recover the energy contained in the flue gases from a glass furnace. The fuel, either fuel oil or methane, can be preheated by the flue gas but only at temperatures below 550° C. Above that temperature decomposition into hydrogen and carbon occurs. Hydrogen is difficult to manipulate safely. Carbon is deposited on the walls of the pipes in the form of tars. The energy gain is slow, less than 50% of the latent heat of the flue gases.
Another proposal is to cause the flue gases to enter a first heat recovery device for storing thermal energy and oxidizing air to enter a second heat recovery device that has stored the thermal energy of the flue gases. Alternation is controlled by a set of valves. This system necessitating high investments offers a good efficiency of approximately 65%. The temperature of the gases at the outlet of the recovery device is of the order of 400° C.
The Applicant has pursued the objective of a major reduction in energy consumption relative to the mass of glass produced.


A long wearing nail enamel topcoat and a method for doubling the wear of nail enamel using the topcoat of the invention.

Nail lacquers represent a major portion of the cosmetic market. These products are used to protect and embellish the nails. Many performance expectations are required from nail lacquers, including smooth application, rapid dry time, and a lustrous appearance. Prehaps the most important parameter is wear. The significance and desirability of achieving maximum wear is apparent when the typical manicure regimen is examined. Ideally, a complete manicure consists of one coat of basecoat applied to all bare nailsites, followed by two coats of shaded lacquer, plus at least one coat of a clear topcoat. Obviously, considerable time and effort are required to complete such a treatment. In light of this rather involved procedure, it is reasonable to conclude that it is desirable to prolong the lift of the manicure as much as possible.
Many efforts have been conducted in order to maximize wear of nail lacquers. Much of this effort has been concentrated on the development of longer wearing shaded nail lacquers. Unfortunately, this is a very difficult task to accomplish. Similarly much experimentation has been performed on basecoats in order to extend wear, but this has proben very difficult.

Long wearing nail enamel topcoat and related methods


A convertible cargo carrier for offering a traveler the advantages of both pulling and pushing systems for use in conveying objects during their travels. The apparatus includes a cargo platform having a base, and a back coupled to the base; a motive structure coupled to the base for moveably supporting the cargo platform above a surface; a handle, coupled to the back, and a rack member, moveably and extendably coupled to the base, including one or more rack motive elements, the rack member including a first mode for engaging the surface with the one or more rack motive elements and a second mode with the one or more rack motive elements disengaged from the surface, the rack member presenting a platform adjacent the cargo platform when in the first mode.

The present invention relates generally to cargo conveyance systems and methods, and more particularly to manual personal cargo carriers used by individuals to move things from one location to another.
When one or more people travel from one location to another, either by foot, car, boat, plane or otherwise, it is often desirable or necessary to move one or more objects between these locations. For many different reasons, it is often inconvenient to carry these objects, whether due to the weight of the objects, the number of the objects, or just the bulk of the objects.
The prior art has developed travel aids for assisting travelers, including wheeled luggage and towable luggage dollies. Wheeled luggage include a number (typically two or four) wheels integrated into a base of each piece of luggage to permit the luggage item to be towed behind the traveler.
The luggage dolly permits the traveler to move objects that do not have integrated wheels because the traveler stacks the objects on a platform and tows the dolly (with the stacked objects) between the locations. These dollies are designed to be convenient by including folding cargo platforms and telescoping bodies to take up reduced space when not in use.
Some manufacturers integrated these luggage dollies directly into selected pieces of luggage, with a towing arm that telescopes out of a back to permit easy towing with a pair of wheels integrated into a base. This development is convenient in that a separate luggage dolly need not be accounted for between towing activities. Some inconvenience was increased for those travelers that used the dolly for conveying multiple objects. There are some specialty luggage items that may be towed in different configurations. For example, a large parallelepiped type of suitcase includes a pair of wheels integrated into one corner for upright pulling while it includes four wheels integrated into one face for converting into a flat cart that may be towed with other objects stacked on top, like a pull-cart.
These prior art systems and methods have limited effectiveness when a person or group of people travels with more objects than the number of people available for towing. Such is the case when a family travels with young children for example. The number of objects that need to be moved exceed the towing capacity of the available towers, again either because of number/weight/size of the collection of objects.
In some travel depots, like airports and train and bus depots, a push-cart is provided for limited use by travelers. These push carts are particularly advantageous in moving large numbers of objects, moving heavy objects, and/or moving bulky objects. Pushing is preferred in some implementations because heavier loads are more easily maneuvered when located out in front of the operator than from pulling the load behind the operator.
In crowded environments or when there is limited space for the operator to move, it is sometimes desirable to pull a cart, however, this pulling method is usually easier when the cargo load is not too large or heavy to fit on the cart. However, unlike a typical two-wheel Pullman-style cargo container, there is some advantage to providing three or more wheels on the floor and a flexible pivot point that lets the operator hold the handle at a comfortable position while maneuvering. This multi-wheel method also allows for a larger cargo payload on the cart than a two wheel Pullman approach. With regards to the advantages of pushing a cart versus pulling, there is the leverage provided and mechanical advantage of having both hands located on the out part of a wide handlebar when maneuvering a cart full of cargo. Having two hands on the handlebar is more practically achieved in a forward moving cart configuration than in a pull mode. It is also easier for the operator to maneuver a cart full of cargo forward when the cart with four wheels on the floor is largely perpendicular to the steering bar and is held rigidly in place to provide maximum leverage when steering and pushing the cart forward (versus the pull technique which provides some pivot movement in the relationship between the cart and the handlebar for user comfort when pulling).
It is desirable to provide an apparatus and method offering a traveler the advantages of both pulling and pushing systems for use in conveying objects during their travels.

Apparatus and method for convertible cargo carrier


A battery including: a plurality of battery cells arranged side-by-side, each battery cell including a terminal tab for delivering power from the cell; a bus plate made of an electrically non-conductive material, the bus plate also having an array of holes formed therein, the array of holes defining a plurality of hole pairs, wherein the terminal tab from each cell of the plurality of cells extends through a corresponding different hole in the array of holes, wherein for each hole pair of the plurality of hole pairs, the terminal tabs extending through that hole pair are folded one over the other to produce overlapping tabs for that hole pair; and a plurality of clamps each of which clamps together the overlapping tabs of a corresponding different hole pair.

In today's high demand for more efficient battery power and the development of thin plate batteries, methods of incorporating these cells into industry applications has led to creating new busing concepts and circuit protection that was not required for past battery technologies. The battery packs must meet the high power demands and be capable of passing large amounts of current safely from the thin plate battery assemblies. Moreover, the thin plate batteries allow one to utilize minimal space for the applications enclosure with all the components required for the battery technology.
Applications for thin plate technologies need to meet both safety and performance requirements. The busing concept described herein introduces a method that can help protect the sensitive packaging of the cell as well as provide all the necessary components required for optimal performance and safety. Certain thin plate chemistry demands more protection than other chemistries thus requiring power regulation and load balancing as well as thermal monitoring and short-circuit protection. The concepts described herein provide methods for integrating both internal and external monitoring applications within the battery package.
With the introduction of the thin plate cells into high-power applications, the high current output levels require busing methods that can handle those current loads with minimal impedance and without any resulting damage to the cells. The anode and cathode plates from which the power is extracted from the battery are of very sensitive parts of the packaging and must be able to withstand vibration. The concepts described herein will allow one to safely bus the batteries together and design a complete, capacity-rated output battery for the required application.
The busing concept described herein utilizes components that enable one to reduce the assembled height of the packaging of the battery pack as compared to prior art. The concept reduces the need for large gauge inter-connect cabling by incorporating bus clamps for the main power inter-connects. Internal monitoring circuitry can also be incorporated into a printed circuit board which is part of the bus assembly. Utilizing all of the components of the concepts described herein will allow a minimal envelope for the battery pack into its enclosure.
This concepts described herein, in their simplicity, should provide an adequate means of interconnecting thin plate battery cells, as sensitive as they are, into a wide variety of fields in the power application industry. The design concepts described herein were initially targeted for military and commercial aircraft applications but can be used in many other applications for the thin plate battery footprint.
In general, in one aspect the invention features a battery including: a plurality of battery cells arranged side-by-side, each battery cell including a terminal tab for delivering power from the cell; a bus plate made of an electrically non-conductive material, the bus plate also having an array of holes formed therein, the array of holes defining a plurality of hole pairs, wherein the terminal tab from each cell of the plurality of cells extends through a corresponding different hole in the array of holes, wherein for each hole pair of the plurality of hole pairs, the terminal tabs extending through that hole pair are folded one over the other to produce overlapping tabs for that hole pair; and a plurality of clamps each of which clamps together the overlapping tabs of a corresponding different hole pair.
Other embodiments include one or more of the following features. The plurality of clamps are made of an electrically conducting material, e.g. copper. The battery further including a plurality of fasteners securing the plurality of clamps to the bus plate, wherein the plurality of fasteners are screws. The plurality of clamps includes a first clamp that clamps the overlapping tabs of each of two neighboring hole pairs and electrically connects the overlapping tabs of those two neighboring hole pairs. The battery further including a plurality of terminal forms, each terminal form located between the two holes of a different hole pair and providing a structure over which the two overlapping tabs for that hole pair are folded. Each of the plurality of terminal forms has rounded upper edges. The plurality of terminal forms are integrally formed parts of the bus plate or the plurality of terminal forms are separate parts that are mounted on the bus plate. The battery further including circuitry mounted on the bus plate, wherein the circuitry is battery monitoring circuitry and/or short protection circuitry, and/or temperature monitoring circuitry, and/or load balancing circuitry. The battery also includes a protection plate mounted on and protecting most of the bus plate. The bus plate is made of a glass fiber resin. The battery cells of the plurality of battery cells are thin plate battery cells.
In general, in another aspect, the invention features a battery including: a plurality of battery cells arranged side-by-side, each battery cell including a first terminal tab and a second terminal tab, said first and second terminal tabs for delivering power from the cell; a bus plate made of an electrically non-conductive material and having a first array of holes and a second array of holes formed therein, the first array of holes defining a first plurality of hole pairs and the second array of holes defining a second plurality of hole pairs, wherein the first terminal tab from each cell of the plurality of cells extends through a corresponding different hole in the first array of holes, wherein the second terminal tab from each cell of the plurality of cells extends through a corresponding different hole in the second array of holes, wherein for each hole pair of the first and second plurality of hole pairs, the terminal tabs extending through that hole pair are folded one over the other to produce overlapping tabs for that hole pair; a first plurality of clamps each of which clamps together the overlapping tabs of a corresponding different hole pair among the first plurality of hole pairs; and a second plurality of clamps each of which clamps together the overlapping tabs of a corresponding different hole pair among the second plurality of hole pairs.
Depending on the configuration, current capacity, and maximum output requirements of the battery, in prior art designs simple wiring of the current from one cell to another necessitated not only numerous interconnections but also space to accommodate that wiring.
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.


A method of manufacturing a semiconductor device, comprising a first step of forming a layer insulation film on a lower layer wiring provided on a substrate and forming a connection hole in the layer insulation film, a second step of forming an alloy layer composed of a first metallic material constituting the lower layer wiring and a second metallic material different from the first metallic material, on the surface side of the lower layer wiring in the region to be a bottom portion of the connection hole, a third step of sputter-etching the alloy layer, and a fourth step of forming a via in the connection hole in the state of reaching the lower layer wiring; and the semiconductor device.

The present invention relates to a method of manufacturing a semiconductor device and a semiconductor device, particularly to a method of manufacturing a semiconductor device and a semiconductor device which are preferable for producing a multi-layer wiring structure by use of a copper (Cu) wiring.
In recent years, attendant on the enhancement of the degree of integration of semiconductor integrated circuit devices (LSIs), the wiring process technology in relation to the higher-speed operation of the LSIs has become deemed more and more important. This is because the increase in the wiring delay time has become conspicuous due to miniaturization of semiconductor devices. For suppressing the increase in the wiring delay time, it is desirable to reduce the wiring resistance and the inter-wiring capacity.
In regard of the reduction in the wiring resistance, investigations have been made of the copper (Cu) wiring which is lower in resistance, as compared with the aluminum alloy wiring which has hitherto been used. On the other hand, in regard of the reduction in the inter-wiring capacity, investigations have been made of insulation films lower in dielectric constant (lower dielectric constant films) as compared with silicon oxide which has hitherto been used as a layer insulation film. It is considered important to introduce a multi-layer wiring structure using a Cu wiring and a low dielectric constant film.
The multi-layer wiring structure as above-mentioned is generally formed by a trench wiring method such as the dual Damascene process (see, for example, G. B. Alers, Electromigration Improvement with PDL TiN(Si) Barrier in Copper Dual Damascene Structure, "INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM PROCEEDINGS", (USA) IEEE, 2002). In such a multi-layer wiring structure, the via is used in the case of connecting upper and lower wirings; in many cases, generally, a structure is adopted in which the via bites into the lower layer wiring side (see, for example, Jason Gill, Investigation of Via-Dominated Multi-Modal Electromigration Failure Distributions in Dual Damascene Cu Interconnects with Discussion of the Statistical Implication, "INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM PROCEEDINGS", (USA) IEEE, 2003). Such a structure is called as an anchor structure, which can conduct the reduction of the wiring resistance by increasing the region of joint between the lower layer wiring and the via.
Here, one example of the method of producing a multi-layer wiring structure in which an anchor structure is formed by use of the dual Damascene process will be described referring to FIGS. 8A to 8B. As shown in FIG. 8A, a lower wiring 15 composed of Cu is provided on the upper side of a wiring trench 13 provided in a layer insulation film 12 on a substrate 11, with a barrier film 14 therebetween. An etching stopper film 16 composed of silicon carbonitride (SiCN) is formed in the condition of covering the lower layer wiring 15 and the layer insulation film 12, and thereafter a low dielectric constant film composed of methyl hydrogen silsesquioxane (MSQ) is formed as a layer insulation film 17 on the etching stopper film 16. Next, a resist mask R provided with a connection hole pattern is formed on the layer insulation film 17 by an ordinary lithographic technique.
Subsequently, as shown in FIG. 8B, etching is conducted using the resist mask R, whereby the layer insulation film 17 is provided with a connection hole 18 reaching the etching stopper film 16. Thereafter, the resist mask R is removed.
Next, as shown in FIG. 8C, a resist mask (omitted in the figure) provided with a wiring trench pattern is formed on the layer insulation film 17 by an ordinary lithographic technique, and thereafter the layer insulation film 17 is provided with a wiring trench 19 in the state of being communicated with the connection hole 18, by etching using the resist mask. Thereafter, the etching stopper film 16 exposed at a bottom portion of the connection hole 18 is removed, whereby the surface of the lower wiring 15 is exposed.
Subsequently, as shown in FIG. 8D, by sputter etching using Ar, the surface side of the lower wiring 15 exposed at the bottom portion of the connection hole 18 is dug, thereby causing the connection hole 18 to reach the inside of the lower wiring 15.
Next, as shown in FIG. 8E, a barrier film 20 is formed on the layer insulation film 17 in the condition of covering the inside walls of the connection hole 18 and the wiring trench 19.
Next, as shown in FIG. 8F, a wiring material film 21 composed of Cu is formed on the barrier film 20 in the condition of filling up the connection hole 28 and the wiring trench 19 provided with the barrier film 20. Subsequently, a heat treatment is carried out, to cause crystal growth of Cu in the wiring material film 21.
Subsequently, as shown in FIG. 9, the wiring material film 21 (see FIG. 1F) and the barrier film 20 are removed by a chemical mechanical polishing (CMP) process until the surface of the layer insulation film 17 is exposed, thereby forming an upper layer wiring 22 in the wiring trench 19 and forming a via 23 in the connection hole 18. As a result, the via 23 is provided in the state of reaching the inside of the lower layer wiring 15, whereby an anchor structure in the condition where the via 23 bites into the lower wiring layer 15 is formed.
In addition, other than the manufacturing method described using FIGS. 8 to 9, a manufacturing method as follows is also carried out generally. First, as has been described using FIG. 8C, the procedure up to the step of removing the etching stopper film 16 at the bottom portion of the connection hole 18 to thereby expose the surface side of the lower wiring 15 is carried out in the same manner as in the above-described manufacturing method. Next, as shown in FIG. 10A, a first barrier layer 20a is formed on the layer insulation film 17 in the state of covering the inside walls of the wiring trench 19 and the connection hole 18.
Subsequently, as shown in FIG. 10B, by sputter etching using Ar, the first barrier layer 20a at the bottom portion of the connection hole 18 is removed, and the surface side of the lower layer wiring 15 is dug, thereby causing the connection hole 18 to reach the inside of the lower layer wiring 15.
Thereafter, as shown in FIG. 10C, a second barrier layer 20b is formed on the first barrier layer 20a in the state of covering the inside walls of the wiring trench 19 and the connection hole 18, thereby forming a barrier film 20 composed of the first barrier layer 20a and the second barrier layer 20b. The subsequent steps are carried out in the same manner as in the manufacturing method described above referring to FIGS. 8F to 9.

Method of manufacturing semiconductor device, and semiconductor device


Methods, systems, and articles of manufacture to improve image recognition searching are disclosed. In some embodiments, a first document image of a known object is used to generate one or more other document images of the same object by applying one or more techniques for synthetically generating images. The synthetically generated images correspond to different variations in conditions under which a potential query image might be captured. Extracted features from an initial image of a known object and features extracted from the one or more synthetically generated images are stored, along with their locations, as part of a common model of the known object. In other embodiments, image recognition search effectiveness is improved by transforming the location of features of multiple images of a same known object into a common coordinate system. This can enhance the accuracy of certain aspects of existing image search/recognition techniques including, for example, geometric verification.

This disclosure relates generally to image-based object recognition. Various feature detection algorithms are used for image-based object recognition. At the most basic level, feature detection algorithms generate descriptors that provide a means to characterize, summarize and index distinguishing features of an image (e.g., shapes, objects, etc.) for purposes of image-based object recognition, search and retrieval. One example of a feature detection algorithm for image-based object recognition is the Scale Invariant Feature Transform (SIFT) feature detection algorithm, such as described in U.S. Pat. No. 6,711,293 to Lowe. For example, the SIFT feature detection algorithm may be applied to an image to generate descriptors for the numerous features within the image.
Machine-based object recognition generally comprises two distinct steps. First, training images of known objects are analyzed using a feature detection algorithm (e.g., a SIFT feature detection algorithm), which generates descriptors associated with features in the image data. Descriptors associated with many different objects can be packaged as a recognition library or database for deployment on a recognition device (e.g., a smartphone). The image and/or the descriptor data associated with a known object is sometimes reference herein as a "document image." That is simply a label to refer to any image information, such as, for example, feature descriptors, which are associated with a known object. Second, the recognition device captures a new "query" image of an object. The device applies the same image processing algorithm to the query image, thereby generating query image descriptors. The device then compares the query image descriptors to the training image descriptors in the recognition library. If there are sufficient matches, typically nearest neighbor matches, then the query image is considered to contain a representation of at least one of the known objects.

This patent is subject to a terminal disclaimer.

Image feature combination for image-based object recognition


A system and processing techniques are provided for automatically detecting when an individual is under surveillance. At least one uniquely identifying characteristic associated with a vehicle or a person in proximity to the individual is detected as the individual moves about a geographic region, such as when the individual is traveling in a car. Positions in the geographic region where the uniquely identifying characteristics are collected and the times of these collections as the individual moves about the geographic region are also captured. Data is stored for detections of the uniquely identifying characteristics, times of detections and the positions where the uniquely identifying characteristics are detected as the individual moves about the geographic region. The stored data is analyzed to determine whether the individual is under surveillance based on (1) a match of the uniquely identifying characteristics with data stored in a database of known surveillance threats (vehicles, individuals or other characteristics) without regard to the time, distance and direction parameters associated with detection of those uniquely identifying characteristics, or (2) at least two detections of the same uniquely identifying characteristics sufficiently separated by time, distance and direction as said individual moves about said geographic region, or (3) based on either (1) or (2).

There are certain individuals who, because of their profession or their celebrity status, wish to know when and if they are subject to personal surveillance as they move about a geographic region. For example, certain public figures, businessmen, law enforcement officials, military personnel, intelligence officers and government officials stationed abroad, may become the target of a surveillance operation. The surveillance operation may be initiated by well-trained experienced individuals, terrorists, or by common criminals or from stalkers. Public figures, such as celebrities or elected officials, may face a kidnapping or stalker threat. In some areas of the world, business personnel constantly face threats posed by kidnappers, robbers, and/or terrorists. Law enforcement officials may face a threat from gang members, organized crime figures, narcotics traffickers, terrorists or common criminals. The threat level is particularly high, for law enforcement officers operating undercover, for those working with confidential informants and for law enforcement officials involved with individuals in a witness protection program. Military personnel and/or intelligence officers serving abroad in hostile locations are constantly as risk due to surveillance threats from local security services as well as terrorist and or criminal elements.
What is needed is a system that automatically monitors certain activity occurring around an individual as the individual moves about a geographic region or locality and alerts the individual when the activity confirms that the individual is under surveillance.

Surveillance detection system and methods for detecting surveillance of an individual


A zoom lens system, in order from an object side to an image side, comprising: a first lens unit having negative optical power; a second lens unit having positive optical power; a third lens unit having negative optical power; and a fourth lens unit having positive optical power, wherein the third lens unit is composed of two or less lens elements, the fourth lens unit is composed of two or less lens elements, the first lens unit has at least one air space between lens elements constituting the first lens unit, and the condition: Dair/fW>0.75 (Dair: an air space located on the most object side in the first lens unit, fW: a focal length of the entire system at a wide-angle limit) is satisfied; an imaging device; and a camera are provided.

1. Field of the Invention
The present invention relates to zoom lens systems, imaging devices, and cameras. In particular, the present invention relates to: a zoom lens system in which even in a configuration that the overall length of lens system is short and the size is small, a wide view angle at a wide-angle limit and a high zooming ratio are obtained and still quick focusing is achieved and, in particular, high optical performance is obtained even in a close-object in-focus condition; an imaging device employing this zoom lens system; and a thin and compact camera employing this imaging device.
2. Description of the Background Art
In the conventional art, in cameras such as digital still cameras and digital video cameras employing an image sensor for photoelectric conversion (simply referred to as digital cameras, hereinafter), increasing demands are present for size reduction and performance improvement.
As zoom lens systems to be employed in digital cameras in which size reduction and performance improvement are achieved as described above, for example, various kinds of zoom lenses having at least a two-unit construction of negative and positive have been proposed in which a first lens unit having negative optical power and a second lens unit having positive optical power are arranged in order from the object side to the image side.
Japanese Laid-Open Patent Publication No. 2005-352428 discloses a zoom lens having a four-unit construction of negative, positive, negative, and positive and achieving magnification change by changing air spaces between individual lens units, wherein in zooming from a wide-angle limit to a telephoto limit, the interval between the first lens unit and the second lens unit is changed so that magnification change is achieved, and wherein the first lens unit is composed of three lenses, the second lens unit is composed of four lenses, the third lens unit is composed of three lenses, and the fourth lens unit is composed of one lens.
Japanese Laid-Open Patent Publication No. 2008-197176 discloses a zoom lens having a four-unit construction of negative, positive, negative, and positive and achieving magnification change by changing air spaces between individual lens units, wherein in zooming from a wide-angle limit to a telephoto limit, the interval between the first lens unit and the second lens unit is changed so that magnification change is achieved, and wherein the first lens unit is composed of three lenses, the second lens unit is composed of three lenses, the third lens unit is composed of three lenses, and the fourth lens unit is composed of one lens.
Japanese Laid-Open Patent Publication No. 2010-122625 discloses a zoom lens having a three-unit construction of negative, positive, and positive and achieving magnification change by changing air spaces between individual lens units, wherein in zooming from a wide-angle limit to a telephoto limit, the interval between the first lens unit and the second lens unit is changed so that magnification change is achieved, and wherein the first lens unit is composed of two lenses, the second lens unit is composed of three lenses, and the third lens unit is composed of one lens.
Nevertheless, each of the zoom lenses disclosed in Japanese Laid-Open Patent Publication Nos. 2005-352428 and 2008-197176 includes ten or more lenses. This causes a high lens cost and further an increased overall length of lens system. Thus, requirements for digital cameras in recent years are not satisfied.
The zoom lens disclosed in Japanese Laid-Open Patent Publication No. 2010-122625 has lenses in a number as small as six, but still has an increased overall length of lens system. Thus, requirements for digital cameras in recent years are similarly not satisfied.

Zoom lens system, imaging device and camera

Panasonic Intellectual Property Management Co., Ltd.


A nuclear magnetic resonance imaging method that utilizes a LINA-EPI gradient pulse sequence, comprising the steps of: generating a LINA-EPI gradient pulse sequence comprising a read gradient, a RF excitation pulse, a slice gradient, and a phase encoding gradient; generating substantially monotonous gradient noise as a result of generating the LINA-EPI gradient pulse sequence, wherein the substantially monotonous gradient noise is substantially without banking and minimizes confounding BOLD effects during imaging; and imaging a test subject using the LINA-EPI gradient pulse sequence.

Magnetic resonance imaging (MRI) techniques enable noninvasive functional brain mapping with high spatial and temporal resolution. Signal detection in functional MRI (FMRI) is based on the blood oxygenation level dependent effect produced by the different paramagnetic and diamagnetic properties of deoxyhemoglobin and oxyhemoglobin. Neuronal activation, via the neurovascular coupling cascade, is associated with an increase of local oxyhemoglogin and a relative decrease of deoxyhemoglobin in the venous bed which enhances signal intensity in T2*-weighted MR-images.
Due to its advantageous flexibility and the astonishingly detailed spatial and temporal information it provides, FMRI has become the most widely used imaging tool for studying brain function in humans. Nevertheless, until recently, the study of the brain's auditory system has progressed at a considerably slower pace than other functional systems. This is because FMRI studies of the auditory system are confounded by problems arising from the high intensity acoustic noise produced by gradient switching during echo-planar imaging (abbreviated "EPI"). In particular, during operation scanner noise arises when pulses of current are passed through the gradient coil for spatial encoding of the MR signal. Since the gradient coil is placed inside a strong magnetic field, a pulsed Lorenz force is induced. This force vibrates the coil structure, which in turn generates a compression wave in the air that is perceived as the "scanner noise." Researchers Hedeen and Edelstein, Magn. Reson. Med., Vol. 37, pp. 7–10, 1997, have shown that the response of an MRI gradient system to pulsed currents is linear. Consequently, the sound spectrum generated by a particular gradient current waveform is the product of the frequency response of the gradient system and the Fourier transform of the waveform. The switched gradient field, which is proportional to the gradient current, along read, phase, and slice directions of a conventional EPI gradient pulse sequence is shown in FIG. 1. FIG. 1 also demonstrates the excitation and acquisition timing of the conventional EPI pulse sequence.
Conventional EPI pulse sequence timing used to acquire a single image slice consists of two parts. First, magnetization is excited with a slice selective (radio frequency) RF pulse, sometimes preceded by a fat suppression pulse, followed by navigator echoes, which takes about 5–30 ms. Second, the magnetization is spatially encoded and acquired during an oscillating read gradient (abbreviated "GR") and a blipped phase encoding gradient (abbreviated "GP"), which takes about 50–130 ms. The read gradient has a trapezoidal or sinusoidal wave form with a period of 0.5 ms to 2.0 ms. The number of positive and negative read gradient lobes is between 50 to 130.
The EPI sequencing thus generates acoustic noise consisting mainly of two components: (1) a first tone with a frequency of 500–2000 Hz and 50–130 ms duration, produced by the read gradient; and (2) an interruption period lasting for 5–30 ms during excitation and navigator echo acquisition, wherein the first tone is interrupted. Consequently, the acoustic noise generated by a conventional EPI pulse sequence is roughly a pulsed tone with frequency of 500–2000 Hz and pulse rate of 7–20 Hz, as visually demonstrated in FIGS. 2a and 2b. It turns out that the human auditory system is particularly sensitive to pulsed tones within this range of pulse, or repetition rates, generated by conventional EPI pulse sequences.
In practice, EPI noise can reach sound pressure levels (SPL) in the range of about 100 decibels (dB), depending on such factors as the specific imaging sequence, type of gradients, brand of scanner, slice thickness, spatial resolution, bandwidth of data acquisition, and size of the subject examined. The background noise that results from generating the EPI pulse sequence actually activates the auditory system and interacts unpredictably with the true experimental stimuli during studies of functional activation tasks, thereby confounding determinations of hearing threshold of experimental stimuli, studies of phonetic discrimination, and studies of foreground-background discrimination. Therefore, contamination of a test subject's response to an experimental auditory stimulus when exposed to environmental noise within the bore of the MRI magnet is of great concern.
As demonstrated by Ogawa et al., Proc. Natl. Acad. Sci., Vol. 89, pp. 5951–5955, 1992, fMRI, which is based on T2* weighted GE-EPI sequences, acquires a differentially high signal in accordance with local blood oxygenation in the brain, an effect known as the "blood oxygenation-level-dependent effect" or "BOLD effect." The proton signal-intensity alterations, or contrast, created by the BOLD effect occurs as a result of magnetic-susceptibility variation in living tissues. In particular, the magnetic susceptibility variation observed as the BOLD effect is caused by deoxyhemoglobin, which is an endogenous paramagnetic contrast agent. Areas in the brain that are relatively metabolically active (i.e., have more neuronal activation) at the time of FMRI scanning consequently have relatively more oxyhemoglobin, due to the neurovascular coupling cascade, and relatively lower levels of deoxyhemoglobin consumption due to increased blood flow in local venous beds. This relative increase in local oxyhemoglobin with a relative decrease in deoxyhemoglobin results in higher signal intensity in the T2*-weighted MR-images, which is observable as the BOLD effect.
Almost exclusively, GE-EPI sequences are used for fMRI, which provides the following advantages: (a) allows for a very quick image capture (i.e., approximately 70–100 ms per slice); (b) offers a good local resolution (i.e., approximately 2×2×2 mm3); and, (c) with respect to the BOLD effect, provides an optimal echo time TE (i.e., approximately 40–70 ms at 1.5 T, or approximately 20–40 ms at 3T). A typical GE-EPI sequence can be divided into two time segments: (1) the slice selective excitation (i.e., RF-pulse, slice selection gradient with refocuser) time segment and (2) the echo-planer acquisition in the k-space (i.e., oscillating reading gradient and phase coding gradients) time segment. A representative illustration of a conventional working GE-EPI pulse sequence used for fMRI is provided in FIG. 3. However, acoustic noise generated by conventional EPI gradients, as discussed above, is characterized by complex bursts occurring with each imaging slice. With fast fMRI, EPI gradients are repeated eight to twelve times per second and the noise generated excites the auditory cortex. Like other sensory systems, the auditory cortex is highly susceptible to stimulus presentation rates in this range, but responses progressively decrease as repetition rates increase as illustrated by FIG. 4.
As mentioned, during scanning repetition of the GE-EPI measuring sequence creates a characteristic noise gradient in the scanner with a loudness of approximately 90–100 dB volume. Specifically, the gradient coils of the scanner generate noise as their polarities are rapidly changed in accordance with the EPI sequence. This characteristic background noise is largely composed of a high-frequency component (approximately 500–1500 Hz generated by the oscillating reading gradients) and a low frequency component (approximately 10 Hz generated by a repetition of the measurement of approximately 100 ms duration, particularly by means of a 100 ms periodic interruption of the oscillating reading gradient by the layer selection gradient). This loud background noise, which can be best appreciated by listening to the sound recording entitled "conventional-EPI-sound.wav," incorporated herein by reference, causes various kinds of negative effects in preclinical and clinical FMRI investigations in animals and humans.
Various workgroups, such as by Seifritz et al. (See Science, Vol. 297, pp. 1706–1708 and supporting online materials, 2002), have confirmed that background noise generated by fMRI scanners during scanning creates a negative, confounding effect on imaging. Conventional GE-EPI gradient noise generated by the MRI scanner results in direct neural activation, with BOLD signal enhancement, in the hearing center of scanned human subjects' brains. Other researchers have shown that conventional GE-EPI acoustic noise of the gradient systems may directly induce neuronal and BOLD activation of the auditory cortices, and in other regions of the brain as well, such as in the visual or motor cortices thereby causing interagonism (See Cho et al., Magn. Reson. Med., Vol. 39, pp. 331–335, 1998). Conventional GE-EPI acoustic background noise of the gradient systems negatively influences cognitive exertion, as well as the neural bases for the same, and is generally perceived by patients and test subjects to be disturbing and unsettling. Other researchers have found that GE-EPI gradient noise specifically diminishes the ability to discriminate acoustic speech stimulation (See Shah et al., Neuroimage, Vol. 12, pp. 100–108, 2000), which is particularly disadvantageous in connection with clinical investigations directed to pre-operative localization of the speech center before a neurosurgical intervention (See Sabsevitz et al., Neurology, Vol. 60, pp. 1788–1792, 2003).
In view of these problems arising from background noise, worldwide intensive research is being conducted to reduce the gradient noise of fMRI sequences and several strategies have emerged to overcome this intrinsic problem. Methods for reducing the affects of gradient noise on the auditory system can be divided into three categories: (a) silent MRI sequences, (b) the use of passive and/or active noise reduction devices, and (c) exploiting the delayed onset of the BOLD signal change that follows acoustic stimulation so as to separate gradient noise from experimental stimuli.
The so-called silent sequences, for example BURST (See Hennig and Hodapp., Magma, Vol. 1, pp. 39–48, 1993, and Jakob P M et al, Magn Reson Med. 1998 October;40(4):614–21) and SIMEX (See Loenneker et al., Magma, Vol. 13, pp. 76–81, 2001) sequence technologies, fundamentally allow the gradient noise to be significantly minimized by generating a sound level that is much lower than the sound level of experimentally delivered stimuli. Silent sequences use slowly changing pulse shapes based on soft, or sinusoidal, ramps for all three gradient axes. This technique is generally not applicable to EPI sequences, but it can be applied to alternative acquisition techniques (i.e., FLASH sequences). While the application of silent sequences to fMRI can provide significant noise reduction reaching noise levels as low as 40 dB, this advantage is achieved, however, with a noticeable loss in temporal resolution of the fMRI measurement. In fact, the reduction in temporal resolution occurs at a factor of up to 300, which leads to significant and generally unacceptable lengthening of the measuring period (e.g., it may take several seconds to for each image slice) needed for clinical or scientific investigation. Consequently, this trade off of diminished temporal resolution in exchange for less gradient noise is impractical because the increased amount of scanning time required to make up for the decreased resolution is not commercially viable.
The BURST technique has been used to generate silent and rapid sequences and overcome the temporal resolution problem. The BURST technique utilizes a train of excitation pulses applied during a single, constant magnetic field gradient. This RF-burst generates a train of echoes that can be acquired with a second, single read-out gradient. As a result, the BURST technique does not require rapidly switched magnetic field gradients, which reduces imaging noise to about 40–50 dB. Compared to EPI, silent BURST offers nearly identical imaging speed; however, signal-to-noise ratio (abbreviated "SNR") is about 5 to 10 times less for BURST sequences than for either new or conventional EPI. In other words, the use of "quiet" fMRI sequences, such as FLASH sequences, results in significantly slower scanning or, in the case of BURST sequences, has an unacceptably bad signal-to-noise ratio compared to EPI sequences.
Other researchers have experimented with methodical approaches for reducing the GE-EPI noise using passive and/or active noise dampening (See Chen et al., IEEE Trans. Biomed. Eng., Vol. 46, pp. 186–191, 1999). The about 10 Hz pulsed background noise generated by the GE-EPI measurement can be passively reduced (e.g., by means of earplugs or headphones) or actively reduced (e.g., by means of a counter noise). The combined use of earmuffs and earplugs can passively attenuate GE-EPI noise by up to 40–50 dB but it cannot be entirely suppressed because noise conduction through body tissue permits up to 50 dB of noise to be conducted to the middle ear.
Active noise dampening techniques utilize an active device that produces a phase-reversed noise emission. If the cancellation noise is emitted inside earmuffs, the technique achieves only about a 20–30 dB reduction in noise because body tissues still conduct noise. While it is difficult to produce noise emissions outside of earmuffs that are exactly phase-reversed to the magnetic gradient noise components, which travel through the body, some success has been achieved by combining active noise reduction techniques with a passive noise reduction technique, thereby achieving noise cancellation as high as 50–60 dB (See Ravicz et al., J. Acoust. Soc. Am., Vol. 108, pp. 1683–1696, 2000). Unfortunately, the characteristic knocking noise (often referred to as "banking") of EPI gradient noise remains. Passive and/or active noise dampening, therefore, does not lead to completely satisfactory noise reduction because the effectiveness of these techniques depend upon both (a) the amount of noise energy, and (b), in particular, the kind of noise. More specifically, GE-EPI magnetic gradient noise is typically pulsed in character (i.e., banked or banking) and results in direct brain activation. Banking GE-EPI noise stimulates the brain in a manner that uses up cognitive resources and disturbs the test subjects despite attempts to actively and/or passively dampen the noise.
The third technique to diminish the effect of background gradient noise on scanning subjects attempts to separate the EPI scanner noise from experimental noise stimuli by taking advantage of the temporal delay separating neural stimulation from its hemodynamical effects and using an intermittent scanning approach. Generally speaking, the BOLD signal change induced by a neuronal stimulation appears only after a delay that is on the order of a few seconds, and the decay of the BOLD signal to baseline equilibrium takes at least 10 seconds. This delay in the hemodynamic response function can be used to disentangle EPI noise from experimental acoustic stimuli. So, a multislice echo-planar slab of the auditory cortex can be sampled a few times as follows: (a) after an auditory stimulation; (b) before the corresponding BOLD signal decays completely; and (c) before the BOLD response to the gradient noise appears. In order to separate EPI scanner noise effects from the experimental noise stimulus effect, the separation of successive acquisition blocks should be long enough to allow the auditory system to recover from the BOLD response of the preceding noise-producing EPI acquisition period, and the scan period must be short enough so that imaging does not pick up the rising limb of the BOLD response to the gradient noise.
From a practical standpoint, to perform these noise separation techniques, certain assumptions must be made. Assuming a delay time of about 2 seconds between stimulus onset and the BOLD response, and a dispersion time of about 2 seconds, then scanning times shorter than 2 seconds and repetition times (abbreviated "TRs") of about 15 seconds or longer should be used. This intermittent scanning approach has been termed "clustered" or "sparse" sampling by some researchers (See Edmister et al., Hum. Brain Mapping, Vol. 7, pp. 89–97, 1999; Hall et al., Hum. Brain Mappling, Vol. 7, pp. 213–223, 1999). However, these intermittent scanning methods are unacceptably time consuming due to the TRs of 15 seconds or more when compared to conventional EPI measurement, which uses TRs of about 1 to 3 seconds.
As indicated above, FMRI scanners and scanning methods of the prior art are unable to satisfactorily address the following technical problem. The characteristic, approximately 8–15 Hz pulsed background noise generated during conventional GE-EPI measurement negatively influences the measurable BOLD effect. So, during fMRI measurement of the auditory system of the brain, the background GE-EPI gradient noise is increased and the reserve capacity of the BOLD signal, and therefore the measurable BOLD signal amplitude, is reduced. In addition, during FMRI measurement of the visual and motor systems of the brain, the BOLD signal is changed by means of complex neural, sensorial and cognitive interactions, although the mechanism responsible for these interactions is not completely understood. Consequently, during fMRI experiments investigating higher cognitive functions, the GE-EPI background noise massively detracts from experiments in cognitive ability by distracting and stimulating the test subjects. This same background noise activates various auditory, visual and motor centers in the brain, thereby distorting measurements determining the connection between cognitive ability and neuronal activation in these test subjects.
Other technical problems are also not adequately addressed by the prior art attempts to reduce GE-EPI background noise effects. For example, during pre-operative clarification studies, particularly when the localization of the speech center is desired, the GE-EPI noise adversely influences the ability to detect and define specific functional centers in a patient's brain, as well as the corresponding associated neural and BOLD activation. Furthermore, the GE-EPI noise is disruptive and uncomfortable for patients and test subjects, and this problem is not adequately mitigated by the prior art technologies.
In summary, the prior art technologies for reducing GE-EPI background noise have proven to be inadequate and/or impractical solutions. Quiet sequences cannot be effectively applied to solve the above-named technical problems because noise reduction can only be achieved with a correspondingly disadvantageous reduction in temporal resolution. This loss of temporal information can only be remedied by a several fold lengthening in clinical and experimental fMRI measurements; however, the required increase in scanning time makes the use of quiet sequences impractical. Passive and active noise reduction methods have also failed to provide a satisfactory solution to the above-mentioned noise-related problems because, while noise attenuation is achieved to some degree, a significant residual amount of "banking" still remains to excite the auditory system. However, whatever advantages obtained using passive and/or active noise reduction methods are at least equally obtainable in connection with the use of the "LINA-EPI" method in accordance with the present invention. Lastly, while prior art intermittent scanning techniques may separate the effect of magnetic field gradient noise from the effects of experimental auditory stimuli, this technique requires an unacceptable increase in the amount of scanning time required and does not actually decrease the level of noise experienced by the test subject.
The present invention endeavors to provide an improved LINA-EPI pulse sequencing method for effectively reducing the GE-EPI background noise of an fMRI scan while maintaining the advantages of the prior art technologies directed to solving this problem.
Accordingly, one object of the present invention is to overcome the disadvantages of the prior art methods for reducing gradient noise.
Another object of the present invention is to lessen activation of the brain's auditory system by undesirable magnetic gradient noise, thereby achieving about a 50% reduction in confounding BOLD signal effects.
A further object of the present invention is to lessen interference (See Cho et al., Magn. Reson. Med., Vol. 39, pp. 331–335, 1998) between auditory activation and activation of other sensorial and senso-motor systems.
A still further object of the present invention is to provide less interference (See Mazad et al., J. Cogn. Neurosci, pp. 172–186, 2002) between auditory stimulation and higher cognitive functions by means of lessening magnetic field gradient noise.
A still further object of the present invention is to lessen interference between auditory stimulation, caused by magnetic field gradient noise, and speech recognition, thereby improving preoperative function testing of the speech system (Shah et al., Neuroimage, Vol. 12, pp. 100–108, 2000).
Yet another object of the present invention is to heightened comfort of the patients and test subjects during MRI investigations by reducing GE-EPI gradient noise.
A still further object of the present invention is to overcome the problems of silent FMRI sequences by achieving satisfactory temporal resolution during FMRI experiments while reducing the impact of magnetic field gradient noise by altering the noise spectrum generated during fMRI scanning.
A yet further object of the present invention is to improve the technical possibilities for reducing effects of magnetic field gradient noise in a scanner, either actively and/or passively.
A still further object of the present invention is to reduce the effective impact of GE-EPI magnetic gradient noise during fMRI scanning procedures without significantly lengthening the scanning period required to generate acceptable images.

Low-impact noise acquisition magnetic resonance imaging


An AC input power converter comprising a rectifier circuit (D3, D4, D5, D6) for rectifying an AC input signal, a first unidirectional device (D1) coupled in series with a first capacitor (C1) for charging the first capacitor (C1) and wherein the first unidirectional device (D1) and the first capacitor (C1) are arranged in parallel to an output of the rectifier circuit (D3, D4, D5, D6), a second unidirectional device (D2) coupled in series with a second capacitor (C2) for charging the second capacitor (C2) and wherein the second unidirectional device (D2) and the second capacitor (C2) are arranged in parallel to an output of the rectifier circuit (D3, D4, D5, D6), a first output (OUT1) for providing a first power and a first average voltage to a first power converter, wherein the first output (OUT1) s coupled to a first node between the first capacitor (C1) and the first unidirectional device (D1) and a second output (OUT2) for providing a second power and a second average voltage to a second power converter, wherein the second output (OUT2) is coupled to a second node between the second capacitor (C2) and the second unidirectional device (D2), wherein the first capacitor (C1) has a first value and the second capacitor (C2) has a second value, and wherein the first value of the first capacitor and the second value of the second capacitor are selected such that when the first power is lower than the second power, the first average voltage is larger than the second average voltage, and when the first power is larger than the second power, the first average voltage is lower than the second average voltage.

Light-emitting diodes (LEDs) are used as a kind of solid-state light source. Compared with conventional lighting, such as incandescent or fluorescent lamps, its advantages are compactness, high efficacy, good color, various and variable color, etc. LEDs are widely used in indoor lighting, decoration lighting and outdoor lighting.
The efficiency of the LEDs keeps on increasing, which increases the efficiency of lighting device during operating mode. However, nowadays, further requirements are put on the stand-by power of a lighting device comprising LEDs. Since the LEDs are turned off during stand-by, the energy consumption of the lighting device is mainly depending on the power converter and the load present at stand-by. Such a stand-by load can be for example wireless communication components, microcontrollers or other components to make sure the lighting device is capable to recover from a stand-by mode. A lot of effort has already been done on improving the efficiency of the stand-by load.
US 2010/0054007 discloses a power supply apparatus with low power in a standby mode. The apparatus includes a voltage multiplier configured to multiply an input voltage and including a first terminal through which the multiplied voltage is output and a second terminal through which a voltage lower than a voltage of the first terminal is output; a main switch-mode power supply (SMPS) configured to receive the voltage of the first terminal of the voltage multiplier; and a standby SMPS configured to receive a voltage of the second terminal of the voltage multiplier.

Apparatus and system for providing a power converter


A roll-up portable table or cooking grill which presents, when in an open first condition for use, a relatively flat, substantially rectangular, upwardly facing table adapted to be supported to define a generally horizontal rigid cooking surface. When in a rolled up second condition for transport or storage, the table is configured to be contained within a generally cylindrical container. The portable table or grill includes a plurality of bars, each having a straight, stiff, longitudinally extending, central rod spaced from and mutually parallel with respect to every other central rod; and two generally J-shaped hook portions, one at each end of that rod. The J-shaped hook portions of each bar each include a shank, a first end of which extends integrally from one end of the rod. These hook portions each include a hook which extends integrally from a second end of the shank. The shanks of the hook portions of each bar extend away from the rod in generally congruent relation to each other while converging slightly toward each other. The hooks of each bar extend from integral connection with their shanks diametrically away from each other and in concentric alignment with each other to lie in parallel relation to the rod of that bar. The bars are so configured that they can be assembled together so as to have both shanks of a leading bar extend under the rod of the next adjacent trailing bar and have both hooks of that leading bar extend outwardly over and above the shanks of that trailing bar.

1. Field of the Invention
This invention relates to portable campfire cooking grills of the type in which a plurality of parallel, spaced apart rods are positioned over a ground-supported campfire or bed of charcoal to broil, boil, fry or otherwise prepare food in an "away-from-home" situation, where such cooking grills must be carried to and from the cooking site whether cleaned or uncleaned, stowed in vehicles and/or backpacked for transport to or from the campsite/-cooking site, and stored at the "home base" between uses.
2. The Prior Art
This invention is an improvement on the inventions of my U.S. Pat. No. 4,977,824, granted Dec. 18, 1990. That patent and all of the references cited therein are incorporated into this disclose by this reference. The inventions disclosed and covered by my earlier patent have proved to be very effective for their intended purposes. A major improvement in this present invention over my earlier inventions is in the development of simplified structures which can be manufactured much more inexpensively, and, therefore, can be sold at a price which will make the grill successful in the marketplace. In addition, all of the advantages of the inventions set forth in my patent are also present in this present invention.