A computer is used to calculate the location of a target, customize the target to conform to the lens, frame and patient characteristics of each individual job and automatically compensate for parallax in the apparatus. A convenient open work surface is provided for the operator to position the lens blank on a non-skid surface. The block is applied at a constant limited force in a manual or automatic mode of operation on either frame or optical center. The offsets for positioning the lens blank are calculated within the blocker based upon frame and patient data. This data can be input directly or can be downloaded from a database. These offsets determine the location of the target relative to the optical markings on the lens blank. The amount the target is offset is scaled automatically to compensate for the fact that the lens blanks are on a work surface above the electronic display. A customized target is displayed. The target is scaled to match the segment widths for multi-focal lenses, and provides a centered target location with multiple horizontal lines for single vision lenses, including progressive lenses. Scaling of the width eliminates operator judgement to "eyeball" the center. The multiple horizontal lines provide an additional aid in aligning progressive lenses where the distance from the "mounting cross" to the horizontal line on the lens blank varies by manufacturer. The frame shape may also be displayed to provide a sense of fit.

This invention relates generally to optical equipment and more particularly concerns apparata for applying a block on a lens blank in preparation for mounting on a grinder.
The placement of a block on a lens must be accurate if the lens is to be correctly positioned in the frame to match the prescription of the patient.
To accomplish this placement, existing blocker type devices presently provide for entering data, displaying a target, displaying the spectacle rim shape and applying the block. However, computations within blockers are minimal. Targets are of a fixed shape with allowance for particular job requirements and judgement is required of the operator to center marks on the lens blank relative to the target. In some cases, clamping devices are used to hold the lens blank. Manually operated blockers are subject to a varying force when the block is applied to the lens blank.
It is therefore an object of this invention to provide a lens blocker which minimizes the need for operator judgment in blocking a lens. It is a further object of this invention to provide a lens blocker which routinely leads an operator through a target customizing process to tailor the target placement and/or configuration to the individual lens, patient and frame characteristics of each job. Another object of this invention is to provide a lens blocker which applies a constant, limited force to the lens during the blocking process. And it is an object of this invention to provide a lens blocker which operates in a variety of modes for direct operator input for calculating the placement of the block based on operator input, or so as to receive frame and/or patient data from measuring equipment and/or from a database. A further object of this invention is to provide a lens blocker that automatically compensates for parallax. Yet another object of this invention is to provide a lens blocker which will allow the operator to confirm the accurate location of the segment relative to the optical center in a multi-focal lens.


Outer cables disposed in a box girder in the longitudinal direction of a box girder bridge to prestress the box girder each have a transparent sheath made of a transparent polyethylene resin, vinyl chloride resin, polypropylene resin or the like, thereby allowing the grouting condition in the sheath to be inspected reliably and easily. If a colored grout is filled, the filling condition can be inspected even more reliably and easily. In addition, it is possible to readily find a portion left unfilled after the grout has hardened and to refill it for repairing by using openings for injection and ejection made at each side of the void left.

Prestressed-concrete structures built by the post-tensioning system include an inner-cable structure in which tendons, e.g. prestressing steel wires or steel strands, covered with sheaths are provided within a concrete member. In such an inner-cable structure, when a grout is filled in the sheaths after prestressing has been done, it is extremely difficult to detect the filling condition of the grout.
In compliance with the demand for a reduction in weight of prestressed-concrete box girders, an "outer-cable structure" has been adopted to reduce the wall thickness of box girder members, in which prestressing tendons are provided out of the concrete members in cross-section of the girder (i.e. in the space inside the box girder cross-section).
The use of the outer-cable structure allows the box girder itself to be reduced in weight and also permits a reduction in material cost and a reduction in work volume required for construction, plus enabling the maintenance and repair of prestressing cables, advantageously. In addition, the reduction in weight of the superstructure leads to a reduction in cost of the substructure (the foundation and piers of a bridge) supporting the superstructure.
In the outer-cable structure, a prestressing tendon that is made up of a large number of prestressing steel wires or steel strands is inserted into a sheath to form an outer cable.
As in the case of the inner-cable structure, tensile stress is applied to the tendon at anchorages provided at both ends of the box girder through anchoring devices to induce compressive stress (prestress) in the concrete girder, thereby improving the load-carrying capacity of the whole box girder.
In the outer cable, a steel pipe or a black polyethylene pipe is generally used as a sheath from the viewpoint of durability. The black polyethylene pipe is formed by mixing an ordinary polyethylene component with carbon black or the like to blacken the polyethylene pipe for the purpose of preventing the material from being deteriorated by ultraviolet exposure.
Incidentally, tendons, which are made of steel, must be subjected to anti-corrosion treatment because of its property. To carry out anti-corrosion treatment for the tendon in the sheath of each outer cable installed in a box girder at a bridge construction site, cement milk or a resin- or oil-based filler is injected into vacant spaces in the sheath as a grout.
Above all, cement milk is a strongly alkaline inorganic grout. Therefore, if cement milk is satisfactorily filled to enclose prestressing steel or the like, which is sensitive to stress corrosion, best durability is exhibited, and high reliability is obtained.
In general, a grout is injected into the sheath by a grout pump from a grout injection hole provided in the anchorage at one end of the sheath, and it is judged that filling of the grout has been completed when the grout has reached the anchorage at the other end of the sheath.
On this occasion, the filling condition of the grout injected into the sheath can be confirmed only indirectly by making a visual check as to whether or not excess grout has been discharged from the upper ends of discharge hoses provided at several positions in an intermediate portion of the sheath. There has heretofore been no technique for directly and reliably confirming or inspecting the filling condition of the grout in the sheath.
There are some advantages in adopting the outer-cable structure for a box girder bridge: reduction in weight of the concrete member; reduction in time and labor required for steel assembling and concrete placing operations; ease of replacing prestressing steel; and ease of improving an existing bridge in maintenance plus load-carrying capacity. To allow these advantages to be surely exhibited, a design of high accuracy and a reliable operation are required at each step of the outer cable installing operation. Above all, an operation of injecting a grout into a sheath enclosing a tendon is one of important factors influencing the performance of a structure with outer cables.
The object in injecting a grout into the sheath of an outer cable is to fill vacant spaces in the sheath with a homogeneous grout and to enclose a tendon made of prestressing steel or the like satisfactorily, thereby taking anti-corrosion measures. That is, in the grout injection operation, reliable and elaborate filling is important. In the conventional method, however, a black polyethylene pipe or a steel pipe is used as a sheath pipe, and it is therefore difficult to inspect or confirm the filling condition of the grout either during or after the grouting operation. In particular, the filling condition of the grout cannot readily be confirmed or inspected by visual observation. Accordingly, the conventional method suffers from serious problems in terms of reliability and so forth.
There has also been proposed a method of inspecting the filling condition of the grout in which ultrasonic waves are transmitted from one end of a sheath at an anchorage and received at the other end to detect an abnormality when the filling is insufficient [for example, see Japanese Patent Application Unexamined Publication (KOKAI) No. 4-182568]. There has also been proposed a method in which elastic waves are propagated from the sheath surface, and the filling condition of the grout is detected from the way in which the elastic waves are received [for example, see Japanese Patent Application Unexamined Publication (KOKAI) No. 10-54140]. However, it cannot be denied that any of the conventional methods involves problems in terms of practicality, e.g. difficulty in installing terminals for transmission and reception, and need of an advanced measuring device and a high level of signal analyzing capacity.
Moreover, outer cables are designed so that they are not only disposed in parallel longitudinally in a box girder but also caused to change in direction vertically by deflectors provided in the box girder. This is done to prestress the box girder not only in the longitudinal direction but also in the vertical direction so as to cope with various stresses induced in the whole concrete structure. Recently, however, size of a tendon has been increased so as to reduce costs of labor relative to post-tensioning operation including pre and post works such as placing ducts and injecting grout. The use of outer cables with an increased outer diameter requires a special consideration to be given to the deflector structure. That is, it is desirable to provide a structure in which the cable surface and the contact surface of each deflector should rub against each other smoothly without producing unnecessary frictional force transmitted through contacting pressure occurring at the deflector to the concrete structure. Accordingly, it has been desired eagerly that outer cables should be capable of meeting such a structural demand appropriately.
It will be apparent that the above-described outer cable structure is applicable not only to concrete box girders but also to steel box girders.

Box girder structure for bridge provided with outer cable and method of building the box girder


An improvement to wavelength modulation spectroscopy systems operating at frequency .OMEGA. and having a photodetector generating output with frequency components .OMEGA., 2.OMEGA., . . . n.OMEGA., where n is an integer greater than one, the improvement comprising a demodulator operating at frequency .OMEGA.+.delta., where .OMEGA.>>.delta., and additionally recovering signals at n.OMEGA.+n.delta.. The system provides information on multiple detection harmonics simultaneously, no phase adjustment is needed, and the system uses a heterodyne demodulation with its inherent low-noise advantage.

1. Field of the Invention (Technical Field)
The present invention relates to an improvement to wavelength modulation spectroscopy.
2. Background Art
Wavelength modulation spectroscopy (WMS) is a form of optical absorption spectroscopy that allows detection of small optical absorbances. The technique is effective because absorption measurements are shifted from frequencies near DC, where light sources are noisy, to high frequencies where shot-noise-limited absorption measurements are possible. This shift in detection band can improve measurement sensitivity by three to five orders of magnitude.
WMS is usually implemented with continuously tunable lasers such as diode lasers. Typically, the wavelength of the light source is modulated by a small amount about an absorption feature of the target species. The modulation frequency is .OMEGA.. As the light beam propagates through a sample, absorption by the target species converts some of the wavelength modulation into amplitude modulation (AM) of the light. When the light impinges onto a photodetector such as a photodiode, the output signal from the detector contains AC components at the modulation frequency, .OMEGA., and its higher harmonics, 2.OMEGA., 3.OMEGA., 4.OMEGA., etc. One of the AC components is selected for measurement using a phase sensitive detector such as a lock-in amplifier or a mixer. This signal processing step is known as demodulation and the signal obtained by demodulation at frequency n.OMEGA. is known as the nf signal. Usually a portion of the modulation waveform is used to generate a reference waveform (local oscillator) for the demodulator. The demodulated signal is related to the optical absorbance and to the intensity of the light beam.
Detailed theory describing WMS and the relationships between the absorption lineshape and demodulated lineshapes is given by Silver, "Frequency-modulation spectroscopy for trace species detection: theory and comparison among experimental methods," Applied Optics 31, 707-717(1992). In qualitative terms, the waveform produced by slowly stepping the average laser wavelength across an absorption line while demodulating at frequency n.OMEGA. looks like the nth derivative of the absorption lineshape.
The shape of a wavelength modulated spectrum depends strongly on the ratio of the extent of the wavelength modulation to the linewidth of the absorption feature. Any phenomenon that changes the absorber linewidth, such as variations in sample pressure or, to a lesser extent, variations in sample temperature, will change the shape and peak intensities of the corresponding wavelength modulation spectrum. Changes in absorber linewidth can, therefore, introduce error into quantitative applications of WMS. The present invention provides method and apparatus that improve WMS by reducing the measurement uncertainty resulting from such changes.
A number of methods exist that can be used to correct wavelength modulation spectra for changes in the absorber linewidth; each of these approaches, however, has some substantial limitation. For example, Wilson, "Modulation broadening of NMR and ESR line shapes," J. Appl. Phys. 34, 3276-3285 (1963), showed that the exact shape of a wavelength modulation spectrum ran be used to extract the absorber linewidth and, thereby, calculate the actual optical absorbance and the species concentration. Wilson's method, however, requires large signal-to-noise ratios in the WMS measurements in order to obtain accurate linewidths, absorbances, and species concentrations.
Goldstein, et al., have developed an improvement to wavelength modulation spectroscopy in which the detector signal at twice the modulation frequency (2.function.) is monitored while the extent of the wavelength modulation is changed. Goldstein, et al., "Gaseous Species Absorption Monitor," U.S. Pat. No. 5,026,991; and Goldstein, et al., "Measurement of molecular concentrations and line parameters using line-locked second harmonic spectroscopy with an AlGaAs diode laser," Appl. Opt. 31, 3409-3415 (1992). The response of the 2.function. signal is representative of the shape and width of the absorption line. Goldstein, et al.'s invention is simple to implement since it requires only a minor modification to standard WMS instrumentation. The most significant limitation of the invention, however, arises because lasers often respond non-linearly to applied modulation waveforms. Both the extent (depth) of modulation and the time dependence of the output wavelength may not track well the changes in the applied modulation signal. Proper implementation of the invention may require careful calibration of the response of each laser or using customized (i.e., non-sinusoidal) modulation waveforms. The non-linearities are particularly important when relatively large wavelength excursions are needed, such as occur for detecting absorbances from samples at atmospheric or higher pressure or from samples at high temperatures.
Species concentrations inferred from wavelength modulation spectra can be corrected by measuring sample temperature and pressure, and using corrections calculated from basic theory or from tabulated calibrations. The computational approach can be slow, however, and requires a significant amount of computing power, tabulating a set of corrections requires a lengthy and tedious calibration. In both cases, the instrument is made more complex and more expensive by adding pressure and temperature sensors.
Some of the demodulation and signal processing techniques employed by the present invention are known in the field of phase fluorometry. Berndt et al., "Fluorometry method and apparatus using a semiconductor laser diode as a light source," U.S. Pat. No. 5,196,709; Lakowicz et al., "Method and apparatus for multi-dimensional phase fluorescence lifetime imaging," U.S. Pat. No. 5,485,530; and Thompson et al., "Phase fluorometry using a continuously modulated laser diode," Anal. Chem. 64, 2075-2078 (1992). Demodulation of high frequency signals makes possible measurement of the phase lag, or time delay, between excitation of a fluorophore and fluorescence emission. These measurements can be used to determine fluorescence lifetimes, including deconvolution of multiple exponential decay rates (lifetimes). Phase fluorometry differs significantly from the present invention in several key ways: 1) the present invention measures optical absorption, not fluorescence; 2) the present invention is best performed using continuous wave (cw) light sources, whereas phase fluorometry requires amplitude modulated or pulsed light sources; 3) phase fluorometry relies on the amplitude modulation of the light source having many frequency components--effected either by varying the frequency of a sinusoidal amplitude modulation or by using short pulses--whereas wavelength modulation spectroscopy is best performed using a single modulation frequency, and relies on optical absorption to introduce multiple amplitude modulation frequencies onto a wavelength-modulated light beam; 4) the present invention provides information about absorption line shapes, whereas phase fluorometry typically uses a fixed wavelength source and acquires no information about spectral profiles.
The following patents likewise do not teach the present invention nor its objects and advantages:
Wong, "Concentration Detector," U.S. Pat. No. 5,047,639 describes an improvement to wavelength modulation spectroscopy which is useful for quantitave detection of a selected gas or gases using a diode laser. Wong describes 2.function. detection for gas concentration determinations. He employs 1.function. detection for line-locking, and describes using the 2.function. signal as a method for guaranteeing "capture" by the 1.function. error signal. However, Wong uses homodyne, not heterodyne demodulations; requires phase adjustments for all demodulations; and cannot acquire line width information.
Whittaker et al., "Method and Apparatus for Reducing Fringe Interference in Laser Spectroscopy," U.S. Pat. No. 5,267,019, also describes an improvement to wavelength (or frequency) modulation spectroscopy for use in detecting gases using diode laser;. Whittaker '019 achieves absorbance measurements with a reduction in unwanted optical interference fringes (etalons) by modulating the laser wavelength at two frequencies simultaneously and by performing sequential demodulations. While unwanted optical interference fringes can occur during practice of the present invention (and can be seen clearly in the phaseless WMS spectra shown in FIGS. 3, 4, and 6), the present invention does not address the fringes, nor would one skilled in the art expect the present invention to maximize or minimize the magnitudes of such fringes. Whittaker '019 is distinct from the present invention because he uses homodyne, not heterodyne demodulations; requires phase adjustments for all demodulations; cannot acquire line width information; and the demodulated lineshapes obtained (Whittaker '019 FIGS. 5-8) are significantly distorted relative to standard harmonic lineshapes, which greatly complicates quantitative measurement of absorbance and species concentrations.
Whittaker et al., "Method and Apparatus for Dual Modulation Laser Spectroscopy," U.S. Pat. No. 5,636,035, also describes an improvement to wavelength (or frequency) modulation spectroscopy for use in detecting gases using diode lasers. Whittaker '035 achieves absorbance measurements and laser line-locking by modulating the laser wavelength at two frequencies simultaneously and by performing two sets of sequential demodulations. Whittaker '035 is distinct from the present invention in that he uses homodyne, not heterodyne demodulations; requires phase adjustments for all demodulations; and cannot acquire line width information.
Zybin et al., "Spectroscopic Method with Double Modulation," U.S. Pat. No. 5,640,245, describes an improvement to optical spectroscopy that is best suited to laser light sources, particularly to diode lasers. He performs a wavelength or amplitude modulation of the laser beam at one frequency, f.sub.1, then modulates some optical property of the target species at a second, different frequency, f.sub.2. Improved detection limits are possible by demodulating the detector output at the sum frequency, f.sub.1 +f.sub.2 ; or at the difference frequency, f.sub.2 -f.sub.1 ; or at an integral harmonic of the sum or difference; or by using two demodulators in series with the first demodulator referenced to f.sub.1 and the second demodulator referenced to f.sub.2. Zybin's invention has relatively few applications, however, because it is usually difficult to find a straightforward method for modulating a useful optical property of the target species. Zybin's approach is most useful for detecting species in AC plasmas since species concentrations often vary synchronously with the plasma frequency. But, other applications listed by Zybin, such as changing the optical path length using "an electrically adjustable system of mirrors," are not feasible at the high frequencies, i.e., above 100 kHz, recommended in the description of the invention and, when implemented, may introduce other error sources such as unwanted optical interference fringes (etalons). More importantly, Zybin does not anticipate the present invention. As with Wong and with the two Whittaker patents, Zybin uses homodyne, not heterodyne demodulations; requires phase adjustments for all demodulations; and cannot acquire line shape information.
Lehmann, "Ring-Down Cavity Spectroscopy Cell Using Continuous Wave Excitation for Trace Species Detection," U.S. Pat. No. 5,528,040, describes a highly sensitive implementation of optical spectroscopy that is useful with diode lasers. His approach differs significantly from the instant invention and from the prior art cited above in that neither wavelength modulation nor frequency modulation techniques are used. Instead, weak optical absorbances are detected by using a special, mirrored optical cell that permits optical path lengths in excess of 1 km from a structure that is only about 1 meter long. Since Lehmann performs direct optical absorbance measurements, his invention can provide line width (and line strength) information, yet nothing in Lehmann's patent discloses or obviates the present invention. Key differences between Lehmann's approach and the present invention include: The present invention does not require a special optical cell, and can be used for open path or in situ measurements; and Lehmann does not require any modulation of laser wavelength nor demodulation of the detector output.
McCaul et al., "Gas Spectroscopy," U.S. Pat. No. 5,491,341, describes an optical spectroscopy technique that is well suited to diode lasers for gas measurements. McCaul's only similarity to the present invention is that both provide line width information. The two approaches are distinct, however, in nearly every other detail. Specifically, McCaul measures the optical transmission through a gas at a plurality--usually five--laser wavelengths that are symmetrically disposed about the absorption peak. These measurements provide the peak absorbance, the line width, and the laser wavelength error. The product of the peak absorbance and line width is proportional to the target gas concentration independent of changes in the line width. The laser wavelength error is used to correct the laser wavelength so that the plurality of measurements remains symmetrically disposed about the absorption peak. Other key differences include: (1) The laser wavelength is not varied continuously, as it is in wavelength modulation or frequency modulation spectroscopies. Instead, a sequence of step changes in laser wavelength is employed to obtain the plurality of measurements. Step durations are on the order of 0.5 ms, corresponding to a change rate of about 2 kHz. In contrast, the present invention employs continuous modulation, typically at frequencies of 50 kHz and higher. (2) One result of using step changes in laser wavelength is that synchronous demodulation (either homodyne or heterodyne) is not possible. Instead, McCaul obtains high detection sensitivity using fast subtraction or fast ratioing circuitry to cancel common mode noise between two photodetectors.
Kenny et al., "Method and System for Examining the Composition of a Fluid or Solid Sample Using Fluorescence and/or Absorption Spectroscopy," U.S. Pat. No. 5,491,344, describes an optical method for measuring species concentrations that is far removed from our application. Most importantly, Kenny uses multiple fixed wavelengths to perform absorption and/or fluorescence spectroscopy. Neither wavelength modulation nor detector demodulation are contemplated. Furthermore, the wavelength spacings are typically four orders of magnitude larger than the line widths of the individual rotational lines probed in typical diode laser spectroscopy. This coarse line spacing makes it impossible to obtain line width information. Other key differences include: (1) Kenny uses laser pulses, not a continuous wave (cw) laser beam, which obviates the type of wavelength modulation employed in the present invention; (2) Kenny does claim absorption spectroscopy using incoherent (i.e., lamp) light sources, but only in conjunction with fluorescence measurements made simultaneously with a pulsed laser system; and (3) Kenny does not use a continuously tunable laser but rather a system that can provide a plurality of fixed wavelengths.
Silver et al., "Laser Absorption Detection Enhancing Apparatus and Method," U.S. Pat. No. 4,934,816, describes a method and apparatus for removing the effects of unwanted optical interference fringes. Such fringes can occur during practice of the present invention (and can be seen clearly in the phaseless WMS spectra shown in FIGS. 3, 4, and 6), but the present invention does not address the fringes, nor would one skilled in the art expect the present invention to maximize or minimize the magnitudes of such fringes. More importantly, nothing in Silver anticipates the phaseless WMS technique. Silver is applicable to a wide variety of laser absorption methods (including the present invention) yet places no constraints on the absorbance method used. Silver invokes wavelength modulation spectroscopy in the preferred embodiment only to the extent that it allows high sensitivity absorption measurements such that unwanted optical interference fringes are significant compared with measured absorbances. Silver does not, however, mention limitations of WMS such as the need for phase adjustment or the lack of line shape information.
Bomse et al., "Mass Spectrometric Apparatus and Method," U.S. Pat. 5,015,848, which is in the field of mass spectrometry, has no relation to the present invention except for presence of a common inventor, but is included for sake of completeness.

Phaseless wavelength modulation spectroscopy


A tri-fold protective mailer for a stress-sensitive article. The protective mailer comprises a three-section, substantially-rectangular panel having a pocket on one outermost section for securing the stress-sensitive article. When the mailer is folded, the article is captured between the overlapping sections of the panel such that the stress-sensitive article is inaccessible from the exterior of the mailer. The pocket is positioned and configured such that the mailer can be handled by automated handling equipment without a significant risk of damage to the stress-sensitive article.

This invention relates to mailers and, in particular, to tri-fold mailers which are suitable for securing and protecting mailpieces, such as stress-sensitive articles, for safe handling by automated handling equipment.
The United States Postal Service utilizes high-speed automated handling equipment for sorting the large volumes of mail that it handles daily. To that end, the automated handling equipment utilizes pairs of vertical moving belts arranged in a network to grip and serially transport mailpieces. The moving belts convey the mailpieces at a linear velocity approaching 500 to 600 feet per minute. Each mailpiece is oriented in a vertical plane such that a three (3) inch edge portion of the mailpiece is gripped between the moving belts. A sensor/translator is provided adjacent to the moving belts for identifying a destination post office for each mailpiece. Mailpieces are sorted according to the destination post office and routed by the network of moving belts into assorted collection bins. Changes in direction of transported mail in automated handling equipment are accommodated by providing a drum over which the moving belts are trained at the point where the direction change is to occur. For example, if the mailpiece is moving linearly in a horizontal direction and it is desired to effect a directional change to a different horizontal direction, a drum mounted for rotation about a vertical axis is placed at the change-of-direction point in the path of travel of the opposed belts between which the mailpiece is gripped for transport. As the belts move about the rotating drum, the mailpiece travels through a curved path conforming to the drum periphery and emerges traveling between the moving belts in a new horizontal direction.
Conventional mailers are available for packaging breakable, frangible or stress-sensitive articles, such as compact disks or mini-compact disks, in a manner suited for handling by the automated handling equipment. Automation-compatible mailpieces must comply with postal regulations such as size requirements and address positioning while protecting the stress-sensitive article from damage during sorting by the automated handling equipment, Moreover, postal regulations require the mailer to be flexible enough to be bent and routed about the circumference of a cylindrical drum having an eleven (11) inch diameter and a height of about three (3) inches of the type used in automated handling systems at locations where directional changes occur in the travel path of the belts.
Stress-sensitive articles packaged in conventional mailers have a significant risk of breakage or damage as the mailer is bent about the circumference of the cylindrical drum. As the mailer is conveyed about the exterior of the drum, the stress-sensitive article must curve or bow and will experience a state of tension due to the flexure that can damage or even break the article. Moreover, conventional mailers position the stress-sensitive article such that the moving belts may apply a significant contact pressure to the article capable of damaging the surface of the stress-sensitive article so as to, for example, corrupt the information encoded thereon. Thus, because of these and other significant shortcomings, conventional mailers do not adequately safeguard stress-sensitive articles for handling by automated handling equipment used by the United States Postal Service.
Accordingly, there is a need for a mailer for a stress-sensitive article that can be handled by automated handling equipment and that fully complies with postal regulations while protecting the stress-sensitive article from damage during transit and sorting.
A primary objective of the present invention is to provide a mailer for a stress-sensitive article such that the mailer can be bent and transported about the circumference of the cylindrical drums used in automated handling equipment without damaging the article. A further objective of the present invention is to provide a mailer for a stress-sensitive article that positions the article such that the belts of the automated handling equipment do not contact the area of the mailer containing the article. A particular objective of the invention is to provide a mailer for a stress-sensitive article that can ensure damage-free handling by automated handling equipment of the postal service while securing the article during transit from a sender to a recipient.
According to the principles of the present invention, a mailer is provided having a substantially rectangular first panel with a pair of transversely-oriented free ends and a first and a second transverse fold line. The first and second fold lines have a spaced relationship between the free ends of the first panel so as to divide the first panel into a first and a second outer section positioned longitudinally on opposite sides of a middle section when the mailer is in an unfolded state. A second panel is attached to the first outer section of the first panel. A pocket is collectively defined between the first and second panels and is dimensioned to receive the stress-sensitive article therein. The pocket has an opening facing the first transverse fold line for insertion and removal of the article. To define a folded state for securing the stress-sensitive article, the first outer section is folded at the second transverse fold line over the middle section to sandwich the second panel therebetween. The second outer section is folded over the middle section with the first outer section and the second panel located therebetween for securing the stress-sensitive article such that the article is inaccessible from the exterior of the mailer.
These and other objectives and advantages of the present invention will be more readily apparent from the following detailed description.

Tri-fold protective mailer for stress-sensitive articles


A lubrication system for an aircraft engine includes an engine lubricant tank including at least a supply port hydraulically connectable to the aircraft engine, a lubricant makeup port, and an overfill port, an auxiliary lubricant tank, a lubricant makeup conduit hydraulically connecting the auxiliary lubricant tank to the lubricant makeup port. The lubricant makeup conduit includes a pump operable to move lubricant from the auxiliary lubricant tank to the lubricant makeup port, and an overfill conduit hydraulically connecting the overfill port to the auxiliary lubricant tank. A method of operating a lubrication system of an aircraft engine of an aircraft is also disclosed.

Prior art aircraft engine oil systems are suitable for their intended purposes, but may have drawbacks in certain circumstances. For example, prior art engine oil tanks may be refilled only while on ground using manual human measurement to avoid overfilling or insufficiently filling the engine oil tank. Excessive oil supply above the maximum engine oil tank level may induce accelerated wear to engine shaft seals, while insufficient oil supply may result in low oil pressure. Another reason why prior art systems are refilled only on the ground is that the effective oil level in the engine oil tank varies with varying aircraft attitude and oil temperature. Accordingly, there are typically procedures for the ground crew to follow when refilling prior art oil systems on the tarmac, the procedures including specifications of the tarmac inclination and oil temperature at the time of the oil level check and refill. Thus, improvements to prior art technology could be made.

Aircraft engine lubrication system and method


A method is disclosed for developing a sheet metal forming process prediction method which is based on the application of an anisotropic hardening rule of plasticity in the mathematic theory.

In the stamping industry, shape distortion due to springback from flanging operations is a serious problem. In many cases, manual correction for shape distortion remains the common practice. It is estimated that $100 million dollars is spent each year by North American stamping plants alone to correct shape distortion defects. This concern is even more critical for lightweight materials such as high-strength steel and aluminum. The generation of springback is based on the hardening rule in the mathematical theory of plasticity used in sheet metal forming simulations.
For simplicity, most sheet metal forming simulation codes use the isotropic hardening rule developed by the mathematical theory of plasticity. However, this hardening rule does not produce realistic numerical results when used to analyze cyclic loading and unloading processes, such as those associated with stretching, bending and unbending over a small radius, or straightening an initial wrinkling as happens in a draw forming operation. FIG. 1 shows that the amplitudes of the uniaxial stress under the specified strain history predicted by the isotropic hardening rule are unreasonably high. Therefore, an anisotropic hardening theory to establish the incremental stress/strain relationship should be used for a more exact simulation of sheet metal forming processes.
The simplest anisotropic hardening rule is the kinematic rule by Prager and Ziegler. This hardening rule has been used to simulate the Bauschinger effect. However, for complex loading histories, actual material behavior substantially deviates from that predicted by this kinematic hardening rule. In addition, there is no definite method for determining the tangent modulus for a non-linear hardening material. The hardening rule proposed by Mroz, "On the description of anisotropic work hardening; J. MECH. PHYS. SOLIDS, Vol. 15, pp. 163-175, 1967, based on an observation of material fatigue behavior, is more appropriate for studying the influence of complex loading histories on material behavior which cannot be explained by either the isotropic or the kinematic hardening rule.
FIG. 2 shows the amplitudes of the uniaxial stress predicted by Mroz's rule under the same strain history as that in FIG. 1. Notably, the stress up to A' is identical to that by the kinematic hardening rule for the uniaxial stress case; however, there is no difficulty in determining the tangent modulus for a nonlinear hardening material.
C. Chu in "A three dimensional model of anisotropic hardening in metals and its application to the analysis of sheet metal formability," J. MECH. PHYS. SOLIDS, Vol. 32, pp. 197-212, 1984 extended Mroz's rule to establish a general constitutive equation in terms of the Cartesian tensor for the elastic plastic material in a three dimensional continuum. Unlike the isotropic and kinematic hardening rules, in which a single yield surface is assumed either to expand or translate, respectively, as a result of plastic deformation, Mroz's model introduced the concept of the field of work-hardening moduli which are defined by the configuration of a finite number of initially concentric yield surfaces in deviatoric stress space. The general rules governing the configuration change are that yield surfaces must move as rigid bodies with the loading point when it is in contact with them, and that the surfaces cannot pass through one another. Therefore, the surfaces will become mutually tangent at the loading point. As it passes from the elastic into the plastic region, the loading point will first encounter the smallest yield surface, which has a radius .sqroot.2/3.sigma..sub.0 wherein .sigma..sub.0 is the initial yield stress. This surface will be pushed forward until the next larger surface is reached and then these two surfaces will then move forward together and so on. Each of these yield surfaces has a constant work hardening modulus. Since a surface is permitted only rigid body motion, its size may be used as a parameter to determine the modulus. When the material is deep into the plastic range and there are multiple yield surfaces tangent to one another at the loading point, the instantaneous modulus for continuous loading is the one associated with the largest yield surface in contact. This is the active yield surface. The smaller yield surfaces can become active again whenever unloading and reloading takes place.
The following derives the equations for change-of-yield surface size and central movement. The Von Mises yield criterion in Cartesian coordinate system is used. According to Mroz's rule, the yield's function is written as: EQU r=(3/2) (s.sub.ij -a.sub.ij) (s.sub.ij -a.sub.ij)-k.sup.2 =0(i,j=1,3)(1)
where s.sub.ij are the deviatoric components of the Cauchy stress tensor .SIGMA.a is the position tensor of the center of the active yield surface, and .sqroot.2/3 k is the radius of this surface. Note that the boldface character denotes a tensor, the index denotes its component and the repeated index means summation. The differential form of the yield's function is EQU (3/2) (s.sub.ij -a.sub.ij) (ds.sub.ij -da.sub.ij)-kdk=0 (2)
assuming the yield surface moves along a unit tensor b, the magnitude of da is the increment of the radius of the yield surface. Therefore, ##EQU1## Substituting this equation into Equation 2 yields EQU dk=(3/2) (s.sub.ij -a.sub.ij)ds.sub.ij /k (4)
where ##EQU2## and Equation 3 becomes ##EQU3## If the associated flow rule is assumed, the elastic, plastic constitutive equation can be derived in a procedure similar to that by means of the isotropic hardening rule.
An example depicting the change of active yield surfaces in a process for initial loading, unloading, reloading, unloading again and then reloading in a multiple-dimensional deviatoric stress component space is illustrated as follows:
1. Initial and Continuous Loading. The center of the initial yield surface is at the origin and its radius is .sqroot.2/3.sigma..sub.0 as shown in FIG. 3. One continuously loads to point A.sub.o where the radius of the yield surface is .sqroot.2/3k as shown in FIG. 3. The unit tensor b in Equation (3) is along OA.sub.o. The center of the smallest yield surface with radius .sqroot.2/3.sigma..sub.0 go moves to 0.sub.1.sup.(1).
2. Unloading and Reloading. One unloads inside the smallest yield surface with center at 0.sub.1.sup.(1) and reloads to A.sub.1 with the deviatoric stress increment ds. Using this increment and the unit tensor b, one can compute the center 0.sub.1.sup.(i) of the bigger yield surface and its radius .sqroot.2/3 k.sub.1 from Equations (4) and (5). The updated unit tensor b is along 0.sub.1.sup.(i) A.sub.1 and the center of the updated smallest yield surface is along this line and thus can be located at 0.sub.2.sup.(1) as shown in FIG. 3.
3. Unloading Again and Then Reloading. If one unloads again inside the newest smallest yield surface and reloads into the plastic range again, the center of the active yield surface is along the line 0.sub.1.sup.(i) 0.sub.2.sup.(1). This center cannot go beyond 0.sub.1.sup.(i) as shown in FIG. 3. If it does, the new center will lie on the line OA.sub.o. If continuous loading occurs, the center of the active yield surface cannot go beyond O; otherwise, the yield surface with the radius .sqroot.2/3 k will be active and move to tangent a yield surface with bigger radius than .sqroot.2/3 k and its center still at 0.
The hardening rule proposed by Mroz better explores the influence of complex loading histories on material behavior which cannot be explained by either the isotropic or the kinematic hardening rule. However, Mroz's model cannot accurately predict springback for nonlinear hardening materials. The linear elastic material model underestimates the amount of springback, while the isotropic hardening rule makes wrong predictions.
Accordingly, there is a need for a revised approach to the traditional isotropic hardening rule, one which allows a more accurate simulation of forming processes and particularly the prediction of springback for nonlinear materials.

Method of applying an anisotropic hardening rule of plasticity to sheet metal forming processes


A substrate transporting method includes: after a holding unit of a substrate holding apparatus receives a substrate from one placement location for a substrate and holds it, detecting a first positional deviation of the substrate from a reference position of the substrate on the holding unit; transporting the substrate held by the holding unit to a position facing another placement location; detecting a second positional deviation of the substrate from the reference position of the substrate on the holding unit, when the substrate is located at the position facing the another placement location; calculating, based on the first and second positional deviations, a positional displacement of the substrate relative to the holding unit that occurred during the transporting of the substrate to the position facing the another placement location; and determining whether or not the positional displacement thus calculated falls within a predetermined range.

1. Field of the Invention
The present disclosure relates to a substrate transport method, a substrate transport apparatus, and a coating and developing system including the substrate transport apparatus.
2. Description of Related Art
In the manufacturing process of semiconductor devices or flat panel displays (FPD), a substrate is sequentially transported to a plurality of processing modules by a substrate transport apparatus, where the substrate is subjected to predetermined processes. The substrate transport apparatus includes, for example, a fork for holding the substrate and a base that supports the fork rotatable and movable back and forth.
There are cases where the fork is provided with a vacuum mechanism in order to firmly hold the substrate. Specifically, the fork has a pipe formed inside the fork and opens at the end portion of the fork, suction ports (e.g., three suction ports) communicating with the pipe and opening at the surface of the fork, and pads made of an elastic material or another material disposed to surround each of the suction ports so as to improve the adhesion between the fork and the back surface of the substrate. The pipe is connected to a suction device. With such configuration, when a substrate is mounted on the pads on the surface of the fork, the substrate is pushed toward the pads by suction, whereby it is firmly held by the fork.
However, since the pads contact with the back surface of the substrate, abrasion of the pads may occur. When the pads are abraded, the substrate may shift from the pads during its transportation by the fork, possibly resulting in the substrate to be not appropriately placed on a substrate placement location. Although the abrasion of the pads can be visually inspected during, for example, regular maintenance, it is difficult to quantitatively determine the degree of abrasion. The operated substrate processing system may be driven to stop due to the positional displacement (shift) of the substrate during its transportation.
The factor of the substrate shift is not only abrasion of pads: it may as well be shifted from the pads for reasons such as warpage of the substrate, leakage in the pipe between the suction device and the pads, and reduction in suction force due to a failure in the suction device. These troubles may also cause the substrate to be not appropriately placed on the substrate placement location.
As an example of techniques for correcting deviation in the setting position of a substrate, JP8-031905A and JP2006-351884A disclose such techniques.

Substrate transport method, substrate transport apparatus, and coating and developing system


Frequency domain reflectometer and method of locating faults in a transmission line utilized by the reflectometer are disclosed. The reflectometer suppresses harmonics that may be interpreted as faults that in actuality do not exist. In general, the reflectometer applies a sweep signal to the transmission line in order to obtain a reflected sweep response signal. Then, the reflectometer obtains a sweep response spectrum from the reflected sweep response signal. The reflected sweep response signal includes a plurality of spectral peaks which represent the frequency components of the reflected sweep response signal. Then, the reflectometer mathematically determines which spectral peaks of the reflected sweep response spectrum were generated due to harmonics in the reflected sweep response signal. After determining that a spectral peak is a harmonic of a fundamental spectral peak, the reflectometer subtracts a percentage of the fundamental spectral peak from the harmonic spectral peak, thereby suppressing a harmonic of the reflected sweep response signal. The reflectometer then obtains from the adjusted sweep response spectrum a location of an impedance mismatch in the transmission line.

Community Antenna Television ("CATV") systems are used in a widespread manner for the transmission and distribution of television signals to end users, or subscribers. In general, CATV systems comprise a transmission subsystem and a distribution subsystem. The transmission subsystem obtains television signals associated with a plurality of CATV channels and generates a broadband CATV signal therefrom. The distribution subsystem then delivers the CATV broadband signal to television receivers located within the residences and business establishments of subscribers. The complexity and size of the distribution subsystem requires that operation and performance be periodically tested and/or monitored.
One test often performed by CATV service providers in order to pinpoint problems in the distribution subsystem is fault detection. Fault detection refers to the process of locating faults within the distribution subsystem such as breaks, shorts, discontinuities, degraded components, and improperly terminated transmission lines. Faults within the distribution subsystem are typically characterized by an impedance mismatch. In other words, the impedance of the fault is typically different than the characteristic impedance of the transmission lines of the distribution subsystem. For example, transmission lines in a CATV distribution subsystem typically have an impedance of approximately 75 ohms; however, a short on the transmission line would have an approximately zero impedance and a break would have an approximately infinite impedance.
One problem with faults in the distribution subsystem is that faults, due to their impedance mismatch characteristics, reflect signals transmitted through the distribution subsystem. As a result, beyond cutting off portions of the distribution subsystem in the case of a short or a break, faults in the distribution subsystem may also cause problems throughout the distribution subsystem due to interference from reflected signals. Therefore, it is important for CATV service providers to be able to locate faults within the network in order to cure reception problems of a single subscriber and to remove fault generated interference from the distribution subsystem as a whole.
One way of determining locations of faults within the distribution subsystem is to perform frequency domain reflectometry upon the distribution subsystem. Frequency domain reflectometry utilizes a reflectometer that applies a sweep signal to the distribution subsystem. The sweep signal is an RF signal that is swept from a start frequency to a stop frequency. If an impedance mismatch exists within the distribution subsystem, the impedance mismatch will reflect each transmitted signal back to the reflectometer at the same frequency as the transmitted signal but retarded in phase. As a result of this reflection, a standing wave is generated. The reflectometer measures the level of the standing wave at each swept frequency in order to obtain a reflected sweep response signal. The retardation of the reflected sweep response signal is such that the minimums of the reflected wave will align to 1/2 the wavelength of the impedance mismatch from the reflectometer. Due to this known relationship, the reflectometer may determine the distance from the reflectometer to the impedance mismatch.
A problem with the above frequency domain reflectometry technique is that the reflected sweep response signal typically contains harmonics. Due to these harmonics, the reflectometer may improperly indicate presence of impedance mismatches within the distribution subsystem that do not truly exist. Therefore, there is a need for a frequency domain reflectometer that is capable of removing the harmonics from the reflected sweep response signal so that the reflectometer does not improperly report presence of a truly non-existent impedance mismatch.
One frequency domain reflectometry system that corrects for harmonics is disclosed in U.S. Pat. No. 4,630,228. This system performs two sweeps on the transmission line under test in order to determine location of impedance mismatches. For the first sweep, the system internally couples a known length of reference cable to the transmission line and performs a first sweep upon the transmission line with the reference cable in order to obtain a first sweep response signal. From the first sweep response signal, the reflectometer generates a first sweep response spectrum that includes a plurality of spectral peaks that represent the frequency components of a first sweep response signal The system then decouples the reference cable from the transmission line and performs a second sweep on the transmission line without the reference cable in order to obtain a second sweep response signal. From the second sweep response signal, the reflectometer generates a second sweep response spectrum that includes a plurality of spectral peaks that represent the frequency components of a second sweep response signal.
If a spectral peak of the second sweep response spectrum is representative of an impedance mismatch at a first distance, then the spectral peak will have a corresponding spectral peak in the first sweep response spectrum that is located at the first distance plus the distance of the reference cable. However, if a spectral peak of the second sweep response is generated due to harmonics in the second sweep response signal, then the spectral peak will have a corresponding spectral peak in the first sweep response spectrum that is located at the first distance plus an integer multiple of the reference cable distance. Due to the above relationships, the reflectometer is able to discard spectral peaks that are generated due to harmonics in the sweep response signals by comparing the first sweep response spectrum with the second sweep response spectrum.
One problem with this type of reflectometer is that the reflectometer requires a lengthy reference cable in order to accurately determine which spectral peaks of a sweep response spectrum are truly due to harmonics within the sweep response signal. Alternatively, the above reflectometer may be implemented with a short reference cable; however, such a reflectometer would require the capability to accurately detect small differences in distance. Either of these two approaches adds cost to the reflectometer. The lengthy reference cable approach adds cost due to (i) the reference cable itself and (ii) the space required to house the reference cable. The short reference cable approach adds cost due to the higher quality of components required to accurately detect small differences in distance. Accordingly, there is a need for a reflectometer for locating faults within a transmission line which suppresses harmonics in a reflected sweep response signal without utilizing a reference cable.

Frequency domain reflectometer and method of suppressing harmonics


A projection apparatus comprises a projection control unit, power supply device and fan. The projection control unit generates an image beam. The power supply device comprises a filter and voltage driving unit. The voltage driving unit is coupled to the filter and comprises a voltage-regulation feedback unit and current amplification component. The filter receives a PWM signal and accordingly outputting a first DC voltage. The voltage-regulation feedback unit receives the first DC voltage and outputs a second DC voltage. The current amplification component is coupled to the voltage-regulation feedback unit for receiving an operational voltage and the second DC voltage, current-amplifying the second DC voltage, and accordingly outputting a driving voltage, which is fed back to the voltage-regulation feedback unit. The voltage-regulation feedback unit regulates the driving voltage according to the first DC voltage. The fan receives the driving voltage for releasing heat of the projection control unit.

1. Field of the Invention
The invention relates in general to a power supply device and projection apparatus using the same, and more particularly to a power supply device which regulates voltage by using a voltage-regulation feedback unit or has a protection device, and projection apparatus using the same.
2. Description of the Related Art
The projection apparatus normally uses a fan for releasing heat such that the inner system has a normal operation under suitable environmental temperature. Whether the fan stably operates is related to a power supply device in the projection apparatus.
Referring to FIG. 1, a partial circuit diagram of a conventional projection apparatus is shown. A projection apparatus 100 includes a power supply device 110, a fan 120, and a projection control unit 130. The projection control unit 130 is for generating an image beam. The power supply device 110 includes a bipolar junction transistor (BJT) M1, a metal oxide semiconductor (MOS) transistor M2 and a filter 112. The filter 112 is a LC filter for instance. The transistor M1 has an emitter coupled to a ground voltage, and a collector coupled to an operational voltage Vdd, such as 13V. The MOS transistor M2 has a gate coupled to the collector of the transistor M1, a drain coupled to the operational voltage Vdd and a source coupled to the filter 112. The fan 120 is coupled to the filter 112 and is used for releasing heat of the projection control unit 130.
As shown in FIG. 1, a pulse width modulation (PWM) signal is inputted to a base of the transistor M1 and the transistor M1 performs a power amplification operation on the PWM signal according to the operational voltage Vdd to generate a square-wave voltage Vin. The square-wave voltage Vin is current-amplified via the MOS transistor M2 to generate a voltage Vc, which is inputted to the filter 112. The filter 112 filters out a alternating-current (AC) component of the voltage Vc and accordingly outputs a direct-current (DC) voltage Vout for driving the fan 120. The air flow generated by the fan 120 releases heat of the projection control unit 130 outside the projection apparatus 100 and thus cool down the projection apparatus 100.
However, the operational voltage Vdd coupled to the power supply device 110 has normally 10% variation, which causes a large variation of the DC voltage Vout. As a result, the fan 120 generates loud noise due to rotating too fast or cannot effectively release heat of the projection apparatus 100 due to rotating too slow. Besides, the filter 112 is easily affected by loading on a subordinate circuits, such as the fan 120, and consequently, ripples are generated on waveform of the DC voltage Vout, which causes an unstable operation of the fan 120.
On the other hand, if the subordinate circuit of the power supply device 110 has shortcut situation, such as shortcut of a motor coil of the fan 120, the power supply device 110 without a shortcut protection device to stop an instant large current generated due to the circuit shortcut damages its inner circuit devices.

Power supply device and projection apparatus using the same


A method includes displaying regions in a graphical display. At least two regions correspond to different portions of a representation of an industrial process system. A thumbnail region corresponds to an entirety of the representation of the process system. A viewport region corresponds to a portion of the representation of the process system less than the entirety of the representation of the process system. The viewport region is disposed and movable within the thumbnail region. A current view region corresponds to a current view of the representation of the process system. The current view is associated with the viewport region. The method also includes, responsive to user activation, moving the viewport region within the thumbnail region and updating the current view region. The thumbnail region is configured to identify at least one fault condition indicator outside the viewport region.

Processing facilities are often managed using process control systems. Example processing facilities include manufacturing plants, chemical plants, crude oil refineries, and ore processing plants. Among other operations, process control systems typically manage the use of motors, valves, and other industrial equipment in the processing facilities.
An important function of process control systems is the ability to provide effective tools for operators to monitor and control industrial processes. These tools often include process schematics that graphically illustrate the industrial processes being controlled. In many cases, the process schematics for a large industrial process are divided into sections, so operators are able to view only smaller portions of the industrial process.

Apparatus and method for providing a pan and zoom display for a representation of a process system


A reformer suitable for micro-scale design has horizontal catalyst tube(s) passing through a baffled radiant section for convective and radiant heat transfer to the tube(s). To reduce the footprint and/or to facilitate field assembly a combustion chamber and convection section can be oriented transversely with respect to the radiant section; the tube(s) can be horizontal and/or include structured catalyst; and/or the combustion chamber provides flameless combustion or produces a flame without impinging on the tubes. Also, a skid frame-mountable version of the reformer; and a process for transporting, assembling, and/or operating the steam methane reformer.

A small or "micro" reformer, such as, for example, a steam methane reformer (SMR), is one that produces syngas at a capacity for making between 1 and 100 BPD of liquid hydrocarbons in a Fischer-Tropsch gas-to-liquid (GTL) process. Micro reformers have not generally been used at low capacity, e.g., to process low-Btu landfill gas, or remote or "stranded" natural gas from oil production. SMR reactors typically consist of vertically oriented, catalyst-filled tubes 12 meters or more in length mounted with spring hangers, and have an unacceptably high profile for micro-scale assembly and operation at a remote location. Moreover, operating temperatures of 850° C. and pressures of 15-25 atm complicate cost-effective, small-scale design.
The industry needs a compact, cost-effective reformer design having a lower profile that can be assembled on a single level without stacking and/or on a smaller footprint, suitable for skid mounting, transport, and/or assembly, yet is operable at a low capacity with high efficiency, low methane slip, and low NOx emissions.


Provided are embodiments for a resistor array. The resistor array includes a plurality of resistor elements, where the plurality of resistor elements includes a redundancy region for a most significant bit of an expected value. The resistor array also includes one or more switches coupled to the plurality of resistor elements, and a first terminal and a second terminal coupled to the plurality of resistor elements. Also provided are embodiments for trimming the resistor array where the resistor array includes a redundancy region for a most significant bit for an expected value.

The present disclosure is generally related to resistor array circuits and more particularly to redundant resistor networks.
Resistor networks include multiple resistors that can be provided in a known pattern. These resistor networks can be implemented in a variety of configurations and used for various applications. Such applications can include analog-to-digital conversion, digital-to-analog conversion, voltage dividers for power functions, computer applications, and more. There may be a need to improve the accuracy in the tunability of the resistor networks based on its application.


The present invention relates to a system and method that provide for automated notification to entities (e.g., individuals, groups of individuals, computers, systems . . . ) of welding system related information. The invention provides for determination of events and/or conditions that warrant automatic notification thereof to relevant entities. The notifications are conveyed via a most appropriate subset of available communication modes available. The system identifies most appropriate entities to receive the notification about the event, and optionally determines or infers state of the entities and conveys the notification via a communication mode (e.g., text, audio, graphical, video, combination thereof . . . ) and modality (e.g., wireless, Ethernet, cable, optical, telephone, e-mail, voicemail, pager, ghosting, instant messaging . . . ) that is most suitable given context/state of the event and entities.

Welding systems reside at the core of the modem industrial age. From massive automobile assembly operations to automated manufacturing environments, these systems facilitate joining in ever more complicated manufacturing operations. One such example of a welding system includes an electric arc welding system. This may involve movement of a consumable electrode, for example, toward a work piece while current is passed through the electrode and across an arc developed between the electrode and the work piece. The electrode may be a non-consumable or consumable type, wherein portions of the electrode may be melted and deposited on the work piece. Often, hundreds or perhaps thousands of welders are employed to drive multiple aspects of an assembly process, wherein sophisticated controllers enable individual welders to operate within relevant portions of the process. For example, some of these aspects relate to control of power and waveforms supplied to the electrode, movements or travel of a welding tip during welding, electrode travel to other welding points, gas control to protect a molten weld pool from oxidation at elevated temperatures and provide ionized plasma for an arc, and other aspects such as arc stability to control the quality of the weld. These systems are often deployed over great distances in larger manufacturing environments and many times are spread across multiple manufacturing centers. Given the nature and requirements of modem and more complex manufacturing operations however, welding systems designers, architects and suppliers face increasing challenges in regard to upgrading, maintaining, controlling, servicing and supplying various welding locations. Unfortunately, many conventional welding systems operate in individually controlled and somewhat isolated manufacturing locations in regard to the overall joining, fabrication and/or other production process. Thus, controlling, maintaining, servicing and supplying multiple and isolated locations in large centers, and/or across the globe, has become more challenging, time consuming and expensive.
The matrix of variables (e.g., performance, wear and tear, diagnostic, prognostic, throughput, quality, timeliness, robustness, extrinsic factors . . . ) results in situations where such variables need to be constantly monitored—which is very expensive. Lack of monitoring can lead to catastrophic failure of machines, lines, parts, leading to potential loss of revenue. However, it is not often practicable to have relevant entities continuously monitoring variables pertaining thereto.
In view of the above, it is submitted that there is an unsolved need for the subject invention, which addresses some of the aforementioned issues in a novel manner.

System and method providing automated welding notification


The present invention relates to a wiper plug and internal drop ball mechanism that may be used in conjunction with a downhole surge reduction tool to run, hang, and cement casing liners in a wellbore. The apparatus of the present invention comprises a wiper plug assembly removably attached to the drill string within the casing liner, a drop ball sub attached below the wiper plug assembly which releases a float valve actuator ball having a diameter larger than the drill string, and float equipment having a plurality of flapper valves. The apparatus of the present invention may further comprise a diverter tool connected between the drill string and the casing liner.

1. Field of the Invention
The present invention relates to an apparatus for running tubular members such subsea casing strings in a wellbore. More particularly the present invention relates to a wiper plug and internal drop ball mechanism that may be used in conjunction with the running and cementing of such tubular members in a wellbore.
2. Description of the Prior Art
In oilfield applications, a xe2x80x9ccasing linerxe2x80x9d and a xe2x80x9csubsea casing stringxe2x80x9d are tubular members which are run on drill pipe. The term xe2x80x9ccasing linerxe2x80x9d is usually used with respect to drilling operations on land, while the term xe2x80x9csubsea casing stringxe2x80x9d is used with respect to offshore drilling operations. For ease of reference in this specification, the term xe2x80x9ccasing linerxe2x80x9d is used to denote either a xe2x80x9ccasing linerxe2x80x9d or xe2x80x9csubsea casing string.xe2x80x9d
Prior art drop ball-actuated float equipment for use in cementing casing liners in place includes, for example, a float shoe or float collar which has one or more flapper valves and which is located at or near the bottom of the casing liner. The flapper valve or valves are conventionally held open by a breakable plastic tab which is actuated (i.e., broken) by a drop ball when the cementing operation is to begin. The industry has traditionally used systems where a drop ball is released at the surface, and the drop ball must be small enough in diameter to pass through the smallest restriction in the drill string, which usually is the diameter of the bore in the running tool. The size of such restrictions has, therefore, limited the maximum size of the opening in a float collar or shoe. In the case of 13xe2x85x9cxe2x80x3 casing liner, the maximum diameter of a drop ball is somewhere between 2 to 3 inches. Due to the small diameter bore of traditional float equipment and the highly contaminated environment in which such equipment is used, the valves in traditional float equipment tend to become plugged with cuttings and contaminants.
As a casing liner is lowered into the wellbore, the fluid in front of the casing liner must be displaced to flow through the opening in the float equipment as well as around the outside annulus defined by the wellbore and the casing liner. The flow resistance of the two flow paths may be high and thus causes a pressure known as surge pressure to build up below the casing liner. This surge pressure can: (a) cause damage to the formation; (b) result in loss of expensive drilling fluid; and (c) result in the casing liner sticking against the side of the borehole, which means the casing liner does not go to the bottom of the hole.
U.S. Pat. No. 5,960,881, which is incorporated herein by reference, discloses a downhole surge pressure reduction system to reduce the pressure buildup while running in a tubular member such as a casing liner. The system is typically located immediately above the top of the casing liner. Nonetheless, any plugging of the float equipment at the lower end of the subsea casing string can, and very well may, render the surge pressure reduction system of the ""881 patent ineffective.
The method and apparatus according to the present invention overcomes the plugging problem and allows enhanced passage of fluid through the tubular member and into the surge pressure reduction tool.
In accordance with the present invention, apparatus is provided for running a tubular member through a wellbore containing drilling fluid using a drill string.
Apparatus in accordance with the present invention comprises a running tool connected to the top of the tubular member having an axial bore therethrough.
Apparatus in accordance with the present invention further comprises a wiper plug assembly which is releasably suspended from a running tool for the wiper plug within the tubular member and having a receptacle sleeve to receive a drill pipe dart. During cementing operations, the wiper plug assembly receives the drill pipe dart and is released from the drill string at the top of the tubular member. The wiper plug assembly is then pumped downward forcing cement out of the bottom of the tubular member and into the annulus between the tubular member and the borehole.
One end of the running tool for the wiper plug is connected to the running tool attached to the tubular member. The running tool for the wiper plug comprises an axially indexing sleeve and a plurality of wedge-shaped fingers which releasably engage the wiper plug receptacle sleeve. During running in of the tubular member, the drilling fluid flows from the casing liner upward through the ports between the fingers and into the void above the wiper plug fins. To isolate the wiper plug fins from internal pressure during cementing operations, the drill pipe sleeve is indexed axially downward to block the ports between the fingers.
Apparatus in accordance with the present invention also comprises a drop ball sub attached to and below the wiper plug assembly within the tubular member. The drop ball sub releases a float equipment actuator ball which is larger in diameter than the smallest restriction in the drill string. When released, the actuator ball drops to the bottom of the tubular member where it actuates float equipment. Once actuated, flapper valves in the float equipment prevent the back flow of cement traveling downward through the tubular member.
Apparatus in accordance with the present invention may further comprise a surge pressure reduction device or diverter tool connected between the drill string and the running tool. When the diverter tool is in an open port position, the drilling fluid may flow upward from inside the diverter tool into the annulus between the casing cemented in place and the drill string. When in a closed port position, the device provides passage for fluid to travel downward through the drill string.


An air conditioning installation for the cabin of a motor vehicle comprises an air treatment and distribution unit having an upstream chamber containing a fan and a downstream chamber containing distribution valves for distribution of treated air to the cabin. The two chambers are separated by an evaporator, through which air is driven by the fan into the downstream chamber. A collector for recovery of condensates is located below the evaporator and drains to outside the vehicle. The installation includes control means arranged to operate an automatic scavenging cycle immediately prior to the start of a period of air conditioning operation. This cycle consists in closing all the distribution valves and then running the fan for a predetermined scavenging period so as to drive the stale air out of the interior of the unit.

It is known to provide air conditioning installations which include a unit for treatment and distribution of air, in which the unit comprises an upstream chamber containing a motorised fan unit and a downstream chamber having distribution valves, the upstream and downstream chambers being separated from each other by an evaporator. A collector for recovering condensate is located below the evaporator. The collector terminates in an outlet which communicates with the outside of the vehicle in which the installation is fitted. The evaporator is arranged to cool a stream of air, which is driven towards the evaporator by the fan of the motorised fan unit and passes from the evaporator to be distributed, under the control of the distribution valves, into the cabin of the vehicle.
In passing through the evaporator, at least some of the humidity which is contained in the blown air stream is extracted from the latter, and collects in the form of condensates in the condensate collector. These condensates are then either treated in various ways known to the person skilled in this art, or they are evacuated outside the vehicle, or both. However, after the installation is turned off, some of the condensate still remains within the air treatment and distribution unit, and undergoes chemical or biochemical changes which tend to render the air which is stagnant within the treatment and distribution unit noxious. As a result, when operation of the air conditioning installation is eventually restarted, the noxious air is conveyed into the cabin of the vehicle, to the discomfort of the occupants.

Method and apparatus for evacuating bad smells for an air conditioning installation for a motor vehicle


A door stop device, includes a blocking mechanism (2) and a guiding arm (1), one of these being fastened to the opening part of the door, the other being fastened to the frame, the blocking mechanism (2) including a braking element (24) pressed against a braking roller (21) which is kept in contact with the guiding arm (1), the axle (22) of the braking roller (21) being allowed to move relatively to the body of blocking mechanism (2) within specified limits, the blocking mechanism (2) also including elastic elements (26) defined to bring braking roller (21) and braking element (24), back in compression against each other. A mobile interface unit (25), allows to modulate the load generated by the elastic elements (26), increasing the load when braking roller (21) is in locked position and decreasing the load when braking roller (21) rotates freely.

The present invention relates to a door stop device, comprising a blocking mechanism and a guiding arm, one of these two elements being fastened to the opening part of the door, the other element being fastened to the frame of the door, the said blocking mechanism including at least one braking element pressed against at least one braking roller which is kept in contact with the guiding arm, the axle of the said braking roller being allowed to move relatively to the body of the blocking mechanism, within specified limits, the said blocking mechanism also comprising elastic means designed to bring back the said braking roller and braking element in a position where they are pressed against each other, allowing in this way to hold the door open in any stable position.
The invention is within the door stop area with applications more specifically in the area of motor vehicles, buildings of any kind and household appliances.


A process for alkylation of benzene, including: feeding benzene, a polyalkylate, and a catalyst to a reactor comprising a first and a second reaction zone; reacting the benzene and the polyalkylate in the first reaction zone under transalkylation conditions to form a monoalkylate product; feeding a C2-C4 olefin to the reactor intermediate the first and second reaction zones; reacting benzene and the C2-C4 olefin in the second reaction zone under alkylation conditions to form additional monoalkylate product; recovering an effluent from the reactor, wherein the effluent comprises benzene, the monoalkylate product, any unreacted C2-C4 olefins, heavy hydrocarbons, and the catalyst; separating the catalyst from the effluent; separating the benzene from the monoalkylate product and the heavy hydrocarbons within the liquid effluent; separating the monoalkylate product from the heavy hydrocarbons within the liquid effluent; and recovering the monoalkylate product.

1. Field of the Disclosure
Embodiments disclosed herein relate generally to catalytic alkylation and transalkylation of benzene using a C2-C4 olefin and a heterogeneous catalyst slurry, which can be continuously replaced during operation.
2. Background
Alkylation refers generally to a type of chemical reaction resulting in addition of an alkyl group to an organic compound. Olefins, such as ethylene, propylene, and butylenes, are well-known alkylating agents, frequently used in synthesis of alkylated derivatives. Alkylation of benzene is a commercially important process, used to increase the octane rating of fuel and to produce valuable chemical feedstocks. For example, alkylation of benzene with ethylene may be used to produce ethylbenzene, which may be subsequently converted to styrene. Similarly, alkylation of benzene with propylene may be used to produce cumene, which may be subsequently converted to phenol and acetone.
A typical benzene alkylation reaction is shown below:

Older alkylation technology, still widely employed in the petrochemical industry, involves the use of a catalyst based on phosphoric acid. Newer technology utilizes non-polluting, non-corrosive, regenerable materials, such as zeolitic molecular sieve catalysts. U.S. Pat. Nos. 4,371,714 and 4,469,908 disclose straight pass alkylation of aromatic compounds using molecular sieve catalysts in fixed beds. However, there are two main problems arising from the use of zeolitic catalysts in alkylation reactions, namely a more rapid deactivation of the zeolitic catalyst due to cooking and poisoning and a higher yield of polyalkylated by-products.
The first problem often results in frequent unit shut downs or other process interruptions, such as for thermal regeneration of the catalyst. U.S. Pat. No. 5,118,897 further discloses a process for reactivating the zeolitic alkylation catalyst by temporary substitution of the olefin supply stream with a hydrogen stream under certain conditions to shorten the thermal catalyst regeneration cycle.
U.S. Pat. No. 5,856,606 discloses a process for alkylating paraffins including a reaction zone containing a pool of liquid maintained at its boiling point and containing a suspended solid catalyst. U.S. Pat. Nos. 5,019,669, 5,080,871 and 5,118,872 disclose a moving bed reaction system for alkylation of aromatic compounds, in which a slurry is produced by adding solid catalyst to the aromatic feed stream into the reactor. The catalyst slurry circulated through the system may be continuously replaced and regenerated during operation, thus reducing the need for unit shut downs. In some embodiments, these patents also suggest inert distillation packing inside the reactive distillation zone and pressure control to adjust the reactor temperature.
The second problem may be addressed by the use of a second reaction zone for transalkylation of polyalkylate by-products with benzene to increase yield of the desired alkylation product. For example, U.S. Pat. No. 4,083,886 describes a process for transalkylation of alkylate aromatic hydrocarbons that uses a zeolitic catalyst in a fixed bed reactor. U.S. Pat. No. 4,891,458 describes the use of beta zeolite for the alkylation or transalkylation of aromatic hydrocarbons with polyalkylate aromatic hydrocarbons. In one embodiment, the process disclosed includes alkylation or transalkylation using a moving bed catalyst with a catalyst regeneration system. In another embodiment, the invention specifies a jacket or condenser type cooler to maintain constant reactor temperature.
Combining alkylation and transalkylation can thus maximize monoalkylate production. Such a combination can be carried out in a process having two reaction zones, one for alkylation and the other for transalkylation, or in a process having a single reaction zone in which alkylation and transalkylation both occur. For example, U.S. Pat. No. 4,008,290 describes a combination process in which the alkylation effluent and the transalkylation effluent are passed from separate reaction zones to a common separation zone, which separates the two effluents into product, by-product, and recycle streams including a recycle benzene stream.
U.S. Pat. No. 5,003,119 describes a combination process for producing monoalkylate aromatics in which the alkylation effluent passes to the transalkylation reaction zone, and the transalkylation effluent passes to a separation zone. In one embodiment, alkylation and transalkylation reactions take place in different reactors. In another embodiment, alkylation and transalkylation reactions takes place either adiabatically or using interstage cooling.
U.S. Pat. No. 5,902,917 describes a process for producing monoalkylate aromatics, wherein a feedstock is instead first fed to a transalkylation zone and the entire effluent from the transalkylation zone is then cascaded directly into an alkylation zone along with an olefin alkylating agent.
U.S. Pat. No. 5,998,684 describes a process for producing alkylate aromatics that operates with an alkylation zone and a transalkylation zone, where the transalkylation zone and the alkylation zone are arranged for series flow and the transalkylation zone effluent is passed with an aromatic containing feed and the olefinic feed, which is preferably propylene or ethylene, to the alkylation zone. In one embodiment, alkylation and transalkylation take place in separate reactors arranged in series.
Although various processes exist for the alkylation and transalkylation of benzene, as described above, there still exists a need in the art for improved processes for the alkylation and transalkylation of benzene and the removal of benzene from various hydrocarbon feeds.


The present invention relates to a process for the preparation of cis-2-tertiary-butylcyclohexanol, where 2-tertiary-butylphenol is hydrogenated in the presence of a nickel/iron catalyst mixture and 2-tertiary-butylcyclohexyl acetate.

The invention relates to a process for the preparation of cis-2-tertiary-butylcyclohexanol from 2-tertiary-butylphenol, the cis-isomer being formed under the hydrogenation conditions.
2-tertiary-butylcyclohexanol, which can arise in the form of the cis and trans stereoisomers, is a valuable intermediate for the preparation of the fragrance 2-tertiary-butylcyclohexyl acetate. In the industrial production of 2-tertiary-butylcyclohexanol, it is desired to obtain large proportions of the cis isomer in order then, by means of transesterification, to obtain cis-2-tertiary-butylcyclohexyl acetate, which is valuable from a perfumery viewpoint and is known under the name Argrumex HC.
For the hydrogenation of 2-tertiary-butylphenol to 2-tertiary-butylcyclohexanol, noble metal catalysts, such as metallic rhodium, rhodium/platinum and rhodium/ruthenium alloys, are known, which are deposited on catalyst supports (JP-A 42-13 938). A disadvantage of the hydrogenation in the presence of a rhodium catalyst is, as well as the high cost of the catalyst, the only low stereoselectivity with regard to the cis-isomer and the decrease in the activity of the catalyst at relatively high temperatures. In addition, tertiary-butylbenzene forms in the rhodium-catalyzed hydrogenation.
DE A 3401343 describes the hydrogenation of 2-tertiary-butylphenol to 2-tertiary-butylcyclohexanol in the presence of palladium and ruthenium, the process being carried out in two stages at hydrogen pressures above 200 bar and temperatures of 70xc2x0-200xc2x0 C. In the first stage, a palladium catalyst is used, and in the second stage, a ruthenium catalyst is used. The cis/trans ratio here is up to 90/10.
JP A 59/065031 describes the hydrogenation of 2-tertiary-butylphenol to 2-tertiary-butylcyclohexanol with Raney cobalt catalysis at 50 bar and 150xc2x0 C., the cis:trans isomer mixture being formed in the ratio 94:6.
DE A 2909663 describes the hydrogenation of 2-tertiary-butylphenol to 2-tertiary-butylcyclohexanol with ruthenium catalysis at 40 bar and 100xc2x0 C., the cis:trans isomer mixture being formed in the ratio 92.5:7.5.
JP A 49/045037 describes the hydrogenation of 2-tertiary-butylphenol to 2-tertiary-butylcyclohexanol with Raney nickel catalysis at 80 bar and 85xc2x0 C. The Raney nickel catalyst is treated prior to use with aqueous sodium boronate solution. Using this catalyst treated in this way, the cis:trans isomer mixture is formed in the ratio 92:8. Without treatment of the Raney nickel catalyst, the cis:trans isomer mixture forms in the ratio 80:20.
A disadvantage of the described prior art is that the service life of the catalyst and the proportion of the cis isomer are inadequate.
Accordingly, it is an object of the present invention to provide a process which produces 2-tertiary-butylcyclohexanol with a high cis isomer content at low cost and guarantees a catalyst service life which is longer than in the prior art.
A process for the preparation of cis-2-tertiary-butylcyclohexanol has been found which is characterized in that 2-tertiary-butylphenol is hydrogenated in the presence of a nickel/iron catalyst mixture and 2-tertiary-butylcyclohexyl acetate.
According to the present invention, preference is given to the use of Raney nickel/iron catalysts. The use of these catalysts in combination with 2-tertiary-butyl-cyclohexyl acetate leads to a 2-tertiary-butylcyclohexanol with a cis/trans isomer mixture of up to 95:5.
By adding 2-tertiary-butylcyclohexyl acetate, the service life of the catalyst can be considerably prolonged. It has been found that the Raney catalyst can be used more than 10 times, if 2-tertiary-butylcyclohexyl acetate is added without the cis:trans ratio falling below 90:10.
Comparative experiments have, on the other hand, shown that without the addition of 2-tertiary-butylcyclohexyl acetate in the hydrogenation, the cis:trans ratio is only 92:8. If the catalyst is used again, the cis:trans ratio decreases even more. When the catalyst is reused for only the third time without the addition of 2-tertiary-butylcyclohexyl acetate, the ratio is only 90:10.
For the process according to the present invention, the catalyst can be used in the dry or moist state.
For the process according to the present invention, in the dry catalyst, the amount of iron is 2-40% by weight, preferably 10-20% by weight; the content of nickel is 60-95% by weight, preferably 70-85% by weight, the content of aluminium is 1-20% by weight, preferably 3-10% by weight.
For the process according to the invention, the weight ratio of the catalyst used to 2-tertiary-butylphenol is (0.0001 to 0.1): 1, preferably (0.01 to 0.03): 1.
The weight ratio of the feed materials 2-tertiary-butylphenol and 2-tertiary-butylcyclohexyl acetate can be 100-0.2:1, preferably 7-9:1.
The reaction temperature for the process according to the invention is 50 to 200xc2x0 C., preferably 90 to 130xc2x0 C.
The hydrogen pressure is 1 to 100 bar, preferably 10 to 20 bar.
The reaction time is 2 to 100 hours, preferably 5 to 20 hours.
The process according to the present invention is generally carried out as follows:
A pressurized container fitted with stirrer is charged with 2-tertiary-butylphenol, 2-tertiary-butylcyclohexyl acetate and the catalyst. Hydrogenation is carried out at the chosen reaction temperature and hydrogen pressure. The resulting cis-2-tertiary-butylcyclohexanol is obtained following removal of the catalyst by filtration, decantation or centrifugation.
The resulting crude mixture can be reacted without further pretreatment with acetic anhydride to give the target product cis-2-tertiary-butylcyclohexyl acetate. Cis-2-tertiary-butylcyclohexyl acetate is a fragrance with woody-fruity properties (S. Steffen Arctander, Perfume and Flavour Chemicals, No. 438, Montclair, N.J., 1969).

Process for the preparation of cis-2-tertiary-butylcyclohexanol by catalytic hydrogenation of 2-tertiary-butylphenol