A method for rapid switching between operating modes with differing beam currents in a charged particle system is disclosed. Many FIB milling applications require precise positioning of a milled pattern within a region of interest (RoI). This may be accomplished by using fiducial marks near the RoI, wherein the FIB is periodically deflected to image these marks during FIB milling. Any drift of the beam relative to the RoI can then be measured and compensated for, enabling more precise positioning of the FIB milling beam. It is often advantageous to use a lower current FIB for imaging since this may enable higher spatial resolution in the image of the marks. For faster FIB milling, a larger beam current is desired. Thus, for optimization of the FIB milling process, a method for rapidly switching between high and low current operating modes is desirable.

In charged particle beam systems, such as electron microscopes or focused ion beam (FIB) systems, a column is typically used to focus a beam of charged particles onto the surface of a target to be imaged and/or processed. In a FIB column, an ion source (typically a liquid metal ion source, or LMIS) generates the initial beam of ions, which then passes into a "gun", which typically focuses these ions into a roughly parallel beam entering the main body of the column. In the column, this beam may be blanked (i.e., turned on and off), deflected (moved around on the target surface), and focused onto the surface of the target. In some cases, the ion beam is used to mill (sputter) material in controlled patterns from the surface of a target—in these applications, the milling rate is roughly proportional to the beam current, thus higher beam currents are generally preferred to improve process throughputs. In other cases, the ion beam is used to image a target, where the impact of the ion beam induces emission of secondary electrons which can be detected and used to form the image—in these applications, the image resolution is roughly determined by the beam diameter. A beam having a lower beam current can typically be focused to a smaller diameter than a beam having a greater current, and the lower beam currents results in less damage to the target. Although an ideal beam would have all the ions uniformly distributed within a desired beam diameter, in actuality, the beam current distribution is more or less bell-shaped and tapers off away from the beam center. The image contrast may be reduced if the focused ion beam has extended "tails".
Some applications require both imaging and milling. In particular, when a milled pattern needs to be precisely located with respect to a pre-existing feature on a target, it is necessary to first image the target with a lower current FIB, and then to switch to a higher current (typically larger diameter) FIB for milling. One important example of such an imaging/milling process is the preparation of thin "lamellae" (singular: "lamella") of various types of samples, such as semiconductor devices and cryo-frozen biological samples. In the case of semiconductor device failure analysis, a particular region of interest (RoI) within an integrated circuit, usually containing a defective device to be analyzed, is exposed by FIB milling on both sides, leaving a thin slice (lamella) of material remaining which contains the defective device—these lamellae are thin enough for use in high voltage transmission electron microscopes (TEMs) or scanning transmission electron microscopes (STEMs) where atomic resolutions are, in principle, available. Because the lamellae are only tens of nanometers thick, and the defects being observed may be on the scale of nanometers, the milling to create the lamella is extremely precise.
During preparation of a lamella, it is necessary to switch between using large current, large diameter beams suitable for rapid milling and using lower current, smaller diameter beams for fine milling or imaging. This is typically done by changing a beam-defining aperture (BDA) through which the beam passes. BDAs are typically holes in a metal strip, allowing only charged particles that pass through the hole to form the beam. There are typically several BDAs, or holes, in a metal strip, and switching apertures typically entails moving the strip so that a hole of a different diameter is positioned in the path of the beam. The mechanical movement of the aperture strip is typically accurate to only a few microns, so it has been considered necessary to realign the beam after changing apertures.
Changing apertures not only necessitated realigning the beam, but also adjustments to the lenses. The optical requirements for forming a large current, large diameter beam and a lower current, smaller diameter beam are not the same. FIG. 28 shows a graph of the logarithm of the spot size of the beam 2810 on a sample as a function of the logarithm of the beam convergence angle 2812. The convergence angle is the angular spread at the target of the ions that are formed into the beam. The aperture in the beam path determines the beam convergence angle—a larger aperture accepts charged particles from a wider angle.
The aperture size affects several properties of the beam. A larger aperture passes charged particles that are further away from the optical axis, thereby increasing spherical aberration (proportional to the cube of the convergence angle) in the beam and, as shown in line 2802, increasing the beam spot size, that is, the beam diameter at the sample. A larger aperture also increases the chromatic aberration (proportional to the convergence angle) as shown by line 2804.
Many charged particle systems form a spot on the sample by forming a demagnified image of the source and the spot size decreases with decreasing magnification (increasing demagnification) as shown by line 2806. The magnification of the optical system decreases with increasing convergence angle. Thus, increasing the convergence angle affects the aberrations and the source demagnification, the aberration tending to increase the spot size with increasing convergence and the source demagnification tending to decrease the spot size with increasing convergence angle.
FIG. 28 shows the combined effects 2808 of spherical aberration, chromatic aberration, and source demagnification on the spot size as the convergence angle changes. At the beam settings for the graph in FIG. 28, the smallest spot size A at the low point of curve 2808 is produced at beam convergence angle B. FIG. 28 shows that if a larger or smaller aperture were used, increasing or decreasing the convergence angle, the spot size would increase, moving away from the low spot in the curve 2808. To return to a more ideal spot size, FIB users would change the lens voltages when changing apertures, to change the magnification and return the beam spot size to a new low point in a modified curve.
Thus, in the prior art, switching between a high current mode and a low current mode has required not only switching of beam-defining apertures, but also realigning the beam and changing numerous lens voltages in order to separately optimize the column ion optics for each of these two modes. Unfortunately, since some column voltages may need to change by substantial amounts (>100 V), long power supply settling times may be required when changing between modes before a column is ready to function, e.g., when switching back-and-forth between milling and imaging. Thus it would be desirable to reduce the switching times between milling and imaging modes in order to improve throughput in the preparation of thin lamellae.

Method for rapid switching between a high current mode and a low current mode in a charged particle beam system


If an electronic camera is set in an image-capturing sensitivity automatic control mode, a program autoexposure calculation is executed based upon the subject brightness and the image-capturing sensitivity setting to determine a control aperture value and a control shutter speed. If the correct exposure is not achieved, a control exposure sensitivity is calculated based upon the exposure deviation and the image-capturing sensitivity setting is adjusted accordingly. If an internal flash unit or an external flash unit is utilized, an autoexposure calculation is executed by using the flash unit synchronizing speed, the subject brightness and the image-capturing sensitivity setting to determine the control aperture value.

1. Field of the Invention
The present invention relates to an electronic camera that captures a subject image with an image-capturing device.
2. Description of the Related Art
An apex operation is performed to determine the correct exposure quantity in a camera in the related art through the following formula (1) by using the aperture value AV of the photographic lens, the shutter speed (exposure time length) TV, the subject brightness BV and the exposure sensitivity SV.EV=AV+TV=BV+SV  (1)EV in the expression above represents the exposure quantity.In a silver halide camera, SV is determined by the sensitivity of the film being used in the camera and, accordingly, the aperture value AV and the shutter speed TV are calculated in correspondence to the subject brightness BV. If the exposure sensitivity SV of the image-capturing device can be varied in an electronic camera, the aperture value AV, the shutter speed TV and the exposure sensitivity SV are calculated in correspondence the subject brightness BV.
Under normal circumstances, if the exposure sensitivity SV is raised in an electronic camera, the noise that is superimposed on image signals increases to result in poor image quality. Accordingly, it is desirable to set an upper limit for the exposure sensitivity SV to ensure that the S/N ratio of the image does not fall below a specific value in an exposure sensitivity change mode which allows the exposure sensitivity SV to be varied. At the same time, a higher priority should be given to achieving the correct exposure than achieving a better S/N ratio for the image in a situation in which full exposure cannot be achieved easily, e.g., during a photographing operation performed in a dark area or during a photographing operation that needs to be performed at a higher shutter speed TV. In order to address this need, an electronic camera that can be set in a sensitivity boost mode in which the exposure sensitivity SV can be set higher than the upper limit has been proposed in the known art. Since the upper limit is set to the exposure sensitivity SV in the exposure sensitivity change mode and the exposure sensitivity SV can be set higher than the upper limit in the sensitivity boost mode, an operational conflict occurs if the two modes are set at the same time.
In addition, the subject brightness BV is often low in a situation that necessitates the use of an electronic flash unit for illuminating the subject. Under normal circumstances, the image-capturing sensitivity SV is adjusted to a higher value in the exposure calculation executed by using formula (1) above if the subject brightness BV is low. In such a case, there is a risk of an increased noise in the image signals to result in degraded image quality and, for this reason, it is better not to change the image-capturing sensitivity. In addition, if no photographic lens is mounted at the electronic camera, lens information such as the aperture value AV necessary for the exposure calculation is not available to the camera, and thus, the image-capturing sensitivity SV cannot be determined accurately. When the full information necessary for the exposure calculation is not available as described above, it is better not to change the image-capturing sensitivity SV that has been set.

Electronic camera that selectively performs different exposure calculation routines


The telecommunications cable of the invention comprises optical fibers and stabilization fibers disposed in an envelope in such a manner as to ensure longitudinal coupling therewith, such that part of the force to which the cable is subjected is shared uniformly over the fibers.

In general, an optical fiber cable comprises optical fibers disposed in an envelope. To ensure good signal transmission, it is generally desirable to keep the mechanical stresses to which the optical fibers are subjected while the cable is being handled down to a minimum, and in particular the stresses that occur during installation and use of the cable. That is why provision has been made over many years to associate optical fibers with a strength member of considerable size that provides decoupling between the structure of the cable, in particular the strength member, and the optical fibers, thereby ensuring that the mechanical forces exerted on the cable (in particular longitudinal forces in traction or compression) are withstood by the strength member.
Decoupling between the strength member and the optical fibers can be obtained during manufacture by providing for the optical fibers to be longer than the strength member, or by interposing layers having a low coefficient of friction and damping layers between the optical fibers and the strength member. Cables of those types are expensive to make and the resulting cable is bulky compared with the number of optical fibers it contains.
In order to mitigate those drawbacks, document FR-A-2 665 266 proposes making an optical fiber cable by providing longitudinal coupling between the optical fibers and the envelope in such a manner that mechanical forces, e.g. traction or compression forces, are shared between the envelope and the optical fibers. In the embodiment described in that document, the optical fibers are subdivided into modules, each of which is enveloped in a module sheath that is in contact with the optical fibers, and the various modules are grouped together in an envelope which is in contact with the module sheaths in order to provide longitudinal coupling therewith. The longitudinal coupling described in that document corresponds in practice to the optical fibers being in a disposition without extra length relative to the envelope, i.e. so that any lengthening or compression of the envelope gives rise to lengthening or compression of the optical fibers.
The force to be withstood by each optical fiber must remain below a threshold above which the transmission properties of the optical fiber are unacceptably degraded relative to the required performance. It will readily be understood that a cable made in that manner can withstand a larger force if it contains a larger number of optical fibers.
Also, when it is desired to manufacture cables of various dimensions, it is necessary not only to have corresponding tooling for making the envelopes, but also to stop the manufacturing line in order to change the tooling. For reasons of manufacturing costs, it is therefore preferable to minimize the number of cables having various dimensions. Also, the cost of optical fibers constitutes a very large fraction of the cost of a cable, so it is not desirable for a cable to have a large number of optical fibers solely for the purpose of distributing forces between them.

SAT Societe Anonyme de Telecommunications


A portion a the machine which the operator regularly engages with his or her hands has incorporated therein a plurality of passageways (14) through which a vacuum is applied to draw vapor which is emitted by the hands of the individual. Vapor from the individual's hands is drawn through a sampling apparatus. The sampling apparatus contains an electrical coil (32, 36, 42, 46) which is coated with a composite metal-nonmetal catalytic substance which causes ethanol to oxidize at the coil. When ethanol-containing vapor passes over the coil, oxidation at the coil causes an electrical charge to build up on the coil. The charge build-up is detected and processed in a discriminating type of electrical circuit which incorporates a wheatstone bridge or a constant-current loop. The resulting signal is further processed then ultimately used to estimate the alcohol content of the individual.

The presence and levels of certain types of toxins in the body of an individual is indicative of the consumption of certain substances which are known to impair the performance capability of an individual. In industry, the level of certain toxins in the body of an employee is used to determine the employee's capability to perform on the job, whether the employee can perform the job safely and whether the employee is in compliance with company policy regarding use Of substances (such as alcohol or cocaine) which produce the toxins. In the medical field the presence of toxins is known to aid in the determination of the origin of loss of motor function and life-threatening coma. In the legal field the specific level of certain toxins in the blood stream is used as an objective indicia of fitness to operate machinery or to drive an automobile or other vehicles. It is particularly important for law enforcement purposes to have simple, fast, convenient, automated qualitative methods of determining whether there are toxins in an individual's blood system such as alcohol and cocaine or metabolites of such substances.
Known methods of integrating a toxin-testing device into a vehicle have been problematic. Examples of such problematic devices are disclosed in U.S. Pat. No. 4,093,945 and U.S. Pat. No. 3,886,540.

System for monitoring and encumbering use of a hand-operated machine by an impaired individual through detection of toxins in the individual


A semiconductor integrated circuit device includes an internal circuit. A plurality of power supply nodes are connected with the internal circuit, and a plurality of pads are respectively connected with the plurality of power supply nodes. A switch section is configured to connect the plurality of power supply nodes one after another in a probe test mode and to separate the plurality of power supply nodes from each other in a product use mode. A power supply voltage is applied to one of the plurality of pads in the probe test mode, and the power supply voltage is applied to each of the plurality of pads in the product use mode. The switch section may include n switches (n is a natural number) provided for the plurality of power supply nodes.

1. Field of the Invention
The present invention relates to a semiconductor integrated circuit to which a power supply voltage is supplied.
2. Description of the Related Art
On a semiconductor wafer, a plurality of semiconductor integrated circuit devices are formed in a matrix as semiconductor chips. In each of the plurality of semiconductor integrated circuits, an internal circuit for attaining a function and electrode pads connected to the internal circuit are formed. For example, after the semiconductor integrated circuit device is produced, an electrical characteristic test is performed on the internal circuit. At this time, if it is determined to be a good product in the electrical characteristic test, a dicing process for cutting the semiconductor integrated circuit devices away from the semiconductor wafer is performed.
The electrical characteristic test includes a probe test. In the probe test, probe needles of a probe card (probe) are pushed against the electrode pads of the semiconductor integrated circuit device, to measure the electric characteristics by using a tester or a storage oscilloscope.
FIG. 1 shows the configuration of a conventional semiconductor system 130 at the time of the probe test to which a semiconductor integrated circuit device 101 is applied. This semiconductor system 130 has a semiconductor integrated circuit device 101 and a probe. The semiconductor integrated circuit device 101 has an internal circuit 102, a plurality of power supply nodes 103-1 to 103-3, and a plurality of bonding pads 104-1 to 104-3. The plurality of power supply nodes 103-1 to 103-3 are connected to the internal circuit 102. The plurality of power supply nodes 103-1 to 103-3 are provided as separated power supplies to reduce mutual interference between noises caused by a high speed operation of the semiconductor integrated circuit device 101. Thus, a same power supply voltage V is applied to the plurality of power supply nodes 103-1 to 103-3. The plurality of bonding pads 104-1 to 104-3 are connected to the plurality of power supply nodes 103-1 to 103-3, respectively. At the time of the probe test, probe needles 131-1 to 131-3 of the probe are pushed to the plurality of bonding pads 104-1 to 104-3, respectively. The probe supplies the power supply voltage V through the probe needles 131-1 to 131-3 to the plurality of bonding pads 104-1 to 104-3, respectively.
In accordance with this electrical characteristic test, whether or not the semiconductor integrated circuit device 101 is good is determined. As a result, in case of a good product, the dicing process for cutting the semiconductor integrated circuit device 101 away from the semiconductor wafer is performed to make it as the product.
FIG. 2 shows the configuration of another semiconductor system 140 (in the state of the product) to which the semiconductor integrated circuit device 101 is applied. The conventional semiconductor system 140 has the semiconductor integrated circuit device 101, a plurality of bonding wires 141-1 to 141-3, and an external power supply 142. In the state of the product, the plurality of bonding wires 141-1 to 141-3 are connected to the plurality of bonding pads 104-1 to 104-3, respectively. The external power supply 142 is connected to the plurality of bonding wires 141-1 to 141-3. The external power supply 142 supplies the power supply voltage V through the plurality of bonding wires 141-1 to 141-3 to the plurality of bonding pads 104-1 to 104-3, respectively.
As mentioned above, the plurality of power supply nodes 103-1 to 103-3 are provided such that one power supply node is separated to reduce the mutual interference between the noises caused by the high speed operation of the semiconductor integrated circuit device 101, in the state of the product. However, at the time of the probe test, although the probe needles 131-1 to 131-3 are brought into contact with the plurality of bonding pads 104-1 to 104-3, respectively, the perfectly same power supply voltage V must be supplied to carry out the electrical characteristic test. The increase in the bonding pads provided in the semiconductor integrated circuit device 101 leads to the proportional increase in the probe needles to be brought into contact with them. Thus, there is a limit on the number of the probe needles that can be measured at one time in the electrical characteristic test. Also, since the probe needle is expensive, the increase in the probe needles to be used results in the increase in cost necessary for the electrical characteristic test. In this way, in the state of the product, it is desired to reduce the noise, and at the time of the probe test, it is desired to decrease the use of the probe needle.
In conjunction with the above description, Japanese Laid Open Patent Application (JP-P2002-245796A: a first conventional example) discloses a semiconductor device. This semiconductor device has a test mode and a usual mode. The semiconductor device has an internal circuit; a test circuit for outputting a control signal to the internal circuit in order to check the function of the internal circuit in the test mode; a first power supply line to supply a power supply current to the internal circuit from an external unit; and a second power supply line which is set to be active in the test mode to supply a second power supply current to the test circuit, and which is set to be inactive in the usual mode. Thus, the consumption current of a memory can be accurately measured without any influence of the consumption current of the test circuit that is used only at a time of an internal test.
Also, Japanese Laid Open Patent Application (JP-P2000-114324A: a second conventional example) discloses a probe card. The probe card is used in a test of a semiconductor device formed in a chip that has first and second pads adjacent to each other in a first direction. The probe card contains a first external circumference layer having first probe needles to be brought into contact with the first pads; and a second external circumference layer that is arranged above the first external circumference layer and has a second probe to be brought into contact with the second pads. The first and second external circumference layers are relatively movable along the first direction. Thus, it can be inspected even when an arrangement pattern of the pads and the chip size are changed.
Also, Japanese Laid Open Patent Application (JP-P2002-111007A: a third conventional example) discloses a semiconductor integrated circuit. The semiconductor integrated circuit includes a first power supply line for supplying a first voltage; a second power supply line for supplying a second voltage lower than the first voltage; a constant voltage generating circuit that is electrically connected to the first and second power supply lines; a third power supply line for supplying a constant voltage that is generated by the constant voltage generating circuit in which the first voltage is defined as a standard; and an operation circuit electrically connected to the first and third power supply lines. At least a part of transistors of the constant voltage generating circuit is formed from first field effect transistors of a partial depletion type having an SOI structure in which a body region and a source region are electrically connected and at least a part of the transistors of the operation circuit is formed from second field effect transistors of the partial depletion type having the SOI structure in which the body region is electrically in an floating state, and the threshold voltages of the first and second field effect transistors are equal. Thus, through the application based on the characteristics of the devices having the SOI structure, the super low power consumption is attained.
Also, Japanese Laid Open Patent Application (JP-A-Heisei 11-74357: a fourth conventional example) discloses an integrated circuit. The integrated circuit has a plurality of terminals. In the integrated circuit, a particular terminal or all of the terminals among the terminals are connected through a switching circuit including a selecting circuit to the power supply line and internal circuit in the integrated circuit, and each of the respective terminals is switched to a signal terminal or power supply terminal. Thus, the particular terminal or all the terminals can be used while their uses are changed to the power supply terminal or the signal terminal.

Semiconductor integrated circuit device with power lines improved


A work vehicle includes an engine mounted on a traveling body, a straight-traveling system transmission path including a first stepless transmission device, and a turning system transmission path including a second stepless transmission device, the work vehicle being configured to combine outputs of the straight-traveling system transmission path and an output of the turning system transmission paths to drive left and right traveling units. The work vehicle also includes control sections that control the outputs of the straight-traveling system transmission path and the output of the turning system transmission paths in cooperation with each other, a transmission operation tool that specifies the output of the straight-traveling system transmission path, and a detector that detects the output of the straight-traveling system transmission path. The control sections select one of an instruction value from the transmission operation tool and an actually measured value from the detector and set the output of the turning system transmission path.

Some conventional work vehicles such as tractors and roller cranes include a work vehicle including two hydraulic stepless transmissions (HST) to which a driving force is transferred from an engine, and each of the two HSTs outputs a straight-traveling force and a turning force based on an engine output. The inventor of this application previously proposed, in Patent Literature 1 (PTL 1), a work vehicle in which a straight-traveling force and a turning force output from each of the two HSTs are combined by left and right planetary gear mechanisms to enable the work vehicle to turn.
Some work vehicles such as a tractor or a wheel loader include a work vehicle in which a hydro-static mechanical transmission (HMT) having a transmission efficiency higher than that of an HST is housed a transmission case to which a driving force is transmitted from an engine. The inventor also previously proposed, in Patent Literature 2 (PTL 2), an in-line hydro-static mechanical transmission in which a hydraulic pump and a hydraulic motor are disposed in line in such a manner that an input shaft of the hydraulic pump and an output shaft of the hydraulic motor are disposed concentrically.
In the in-line hydro-static mechanical transmission, the output shaft is rotatably fitted onto the input shaft to which a driving force is transmitted from the engine. A hydraulic pump, a cylinder block, and a hydraulic motor are also fitted onto the input shaft. The cylinder block alone is used for both the hydraulic pump and the hydraulic motor, and a driving force is transmitted from the hydraulic motor to the output shaft. Thus, unlike a typical hydro-static mechanical transmission, the in-line hydro-static mechanical transmission can combine a shifted driving force by hydraulic pressure and a driving force of the engine without interposition of planetary gear mechanisms so that high power transmission efficiency can be obtained advantageously.

This patent is subject to a terminal disclaimer.


A function generator is described that can be configured as a combinational logic, sequential logic, or routing cell. The function generator couples to a plurality of selector blocks that select a wire from a plurality of inputs. The selected wires are inputs to a function generator. The function generator, when configured as a combinational logic cell, can generate any function of its inputs. The function generator, when configured as a sequential logic cell, behaves as a register, where any of the inputs can be directed to input data, clear, clock enable, or reset signals. The register is configurable to a falling or rising edge flip-flop or a positive or negative level sensitive latch. As a routing element, logic cells selects one of its inputs. The output of the programmable cell can fan out to one or more inputs of another integrated cell.

1. Field of Invention
The invention relates to a programmable integrated cell containing one or more of combinational logic cells, sequential logic cells and routing cells for use in a programmable architecture integrated circuit (IC).
2. Description of Related Art
Field programmable gate arrays (FPGAs) typically enable user programming of integrated circuits (ICs), but typically result in slower performance (clock speed) because of the delays through the transistors, switches or multiplexers used to program the interconnects between configurable logic elements. Each logic element-can be connected to a multitude of other logic elements through switches, in which the path from one programmable logic element to the next may be strewn with many switches, slowing down circuit operation. Some paths in a programmable IC are not as critical as others. Therefore, a customized programmable IC can be designed, where speed in the critical paths are optimized over other non-critical paths.
Routing elements have increasingly been added to programmable logic devices/ICs such that routing elements now typically occupy a much larger area than the configurable logic elements themselves. Adding to the problem is the fact that routing delays are typically much greater than logic delays, resulting in a slow operating clock frequency. In a conventional implementation, a large fraction of the routing elements may be redundant.
Accordingly, it is desirable to have a programmable architecture that provides a greater flexibility of logic and routing elements.

Programmable function generator and method operating as combinational, sequential and routing cells


Apparatus and associated methods may relate to a coded contact information exchange made between source and target electronic devices. In an exemplary embodiment, the coding scheme may be a non-industry standard coding scheme. In an illustrative example, one or more contact fields comprising user contact information are encoded in a barcode format for exchange between the devices. In some examples, the barcode may be transmitted over a non-optical communications link. In other examples, the encoded barcode may be transmitted over an optical communications link. In some examples, the barcode may comprise a two-dimensional barcode. In some examples, the source and target devices may comprise handheld devices, such as mobile phones.

Many people exchange contact information every day. Contact information is commonly exchanged during business occasions as well as personal occasions. There are many tools for recording and storing contact information. One tool for storing contact information may be a paper address book. Another more modern tool for storing contact information may be an electronic device. With the ever-increasing fast-paced society, it is becoming more and more vital to effectively maintain accurate records of contact information.

System for the exchange of optically-encoded information


The invention relates to a reducing agent composition for use in the catalytic reduction process of nitrogen oxides in exhaust gases, the composition containing 20-40 w % of urea, 19-40 w % of ammonium formate, and water.

Nitrogen oxides (NOx) in the exhaust gases from combustion processes constitute a significant environmental hazard, and emissions of nitrogen oxides are subject to increasingly stringent restrictions. Diesel vehicles, especially commercial heavy-duty diesel vehicles, are subject to particularly stringent requirements. Under the Euro IV emission standard taking effect in Europe in 2005, the NOx emissions from heavy-duty diesel engines must not exceed 3.5 g/kWh, whereas the Euro V standard implemented in 2008 will limit the emissions to a maximum of 2 g/kWh.
The amount of nitrogen oxides in exhaust gases can be decreased by reducing these oxides. In principle, compounds containing ammonium nitrogen, such as ammonia, ammonium carbamate, ammonium carbonate, ammonium bicarbonate, ammonium formate, ammonium acetate, ammonium oxalate or ammonium hydroxide, can be used for this purpose.
A notable technical alternative in nitrogen oxide removal comprises the use of selective catalytic reduction (SCR techniques), in which nitrogen oxides are reduced into nitrogen and water by means of a catalyst and a reducing agent. Ammonia and urea have primarily served as reducing agents. The reducing temperature has usually been in the range 265-425° C., typically 300-400° C. For example V2O5-TiO2 catalyst has been used as the catalyst. SCR techniques have the additional benefit of allowing a decrease of the fuel consumption of the engine. Namely, this allows application of higher temperatures, involving more complete combustion but lower nitrogen oxide formation.
In the SCR techniques of vehicles, ammonia and ammonia water involve a problem in terms of operational safety. For this reason, urea, which is almost risk free, is preferably used. Urea is preferred for the additional reason that it contains a double amount of nitrogen per mole compared to the ammonia salts mentioned above. In fact, an aqueous solution of urea is a most appropriate nitrogen oxide remover. Urea is usually dissolved to form an approx. 32.5% by weight solution (e.g. AdBlue, a product name used by VDA), yielding sufficiently high solubility and the lowest resistance to temperature of the solution (−11° C.). Thus, European car manufacturers have chosen these techniques in order to meet the increasingly stringent requirements (Selective Catalytic Reduction, Final Report, ACEA 23, June 2003).
However, in Northern Europe and colder regions in general, the problem is that the outdoor temperature is frequently below −11° C., resulting in an obvious risk of freezing of the urea solution. The risk of freezing is reduced by installing various temperature sensors and resistors, with the primary purpose of preventing freezing or of remelting the frozen urea solution into liquid form. Thus, there have been suggestions to add various additives to a urea solution especially to achieve a lower freezing temperature.
The literature mentions the use of ethanol [F. F. Mao et al. "Urea-ethanol-water solution for diesel NOx control Using Urea", 6th Diesel Engine Emissions Reduction (DEER) Workshop August 20-24] and propylene glycol [Lambert et al. "Application of Organic Freeze-Point Depressant in Aqueous Urea Solution: Effect of Nox Reduction", SAE2003-01-0775] as an anti-freezing agent of an aqueous solution of urea used in the reduction of nitrogen oxides in exhaust gases from a diesel combustion process. In addition, it is generally known to use carboxylic acids for a lower freezing temperature of urea solutions. Such a use has been described e.g. in GB 111936. However, U.S. Pat. No. 6,387,336 states that e.g. ammonium formate is inappropriate for use with the aim to lower the freezing temperature of a urea solution used in an SCR-process, due especially to its corrosive properties.


A user equipment (UE) configured for signaling UE capability is described. The UE includes a processor and instructions stored in memory that is in electronic communication with the processor. The UE sends an indicator regarding whether the UE can support different time division duplex (TDD) configurations on different bands for a band combination. The UE also sends an indicator regarding whether the UE can support concurrent transmission and reception on different bands for the band combination. The UE additionally sends an indicator regarding whether the UE can support different uplink timing adjustments for the band combination.

Wireless communication devices have become smaller and more powerful in order to meet consumer needs and to improve portability and convenience. Consumers have become dependent upon wireless communication devices and have come to expect reliable service, expanded areas of coverage and increased functionality. A wireless communication system may provide communication for a number of wireless communication devices, each of which may be serviced by a base station.
As wireless communication devices have advanced, improvements in communication capacity, speed and/or quality have been sought. However, improvements in communication capacity, speed and/or quality may require increased resources.
For example, wireless communication devices may communicate with one or more devices using multiple channels or cells. However, communicating with one or more devices using multiple channels or cells may pose certain challenges. As illustrated by this discussion, systems and methods that enable or improve communication using multiple channels or cells may be beneficial.


An information input display device, having an input section for inputting information and a display section for displaying the information, which enables an access to protected information after being authenticated by an authentication processing executed after starting up of the information input display device, the information input display device including: an authentication processor which executes the authentication processing based on authentication information inputted by the input section; and an input display controller which, after the starting up of the information input display device and before being authenticated by the authentication processing, accepts inputting of prescribed information different from the authentication information through a screen displayed on the display section, and allows the display section to display the prescribed information on the screen.

1. Technical Field
The present invention relates to an information input display device and a control program thereof, and particularly to an information input display device in which an authentication processing is executed after its startup, and a control program to control information input and display of the information input display device.
2. Background Technology
In recent years, portable devices provided with display sections (hereinafter referred as information input display device), such as notebook-size computer devices and tablet type terminals, are commonly used. In order to ensure security, these information input display devices are configured to display, at the time of starting up the devices, an authentication screen for inputting authentication information such as a user ID or a password, and after the authentication information is validated, variable functions are enable to be usable.
In many cases these information input display devices are being carried by users, they are becoming to be used not only for simply displaying the information, but as a notepad for inputting comments or messages, and for displaying the inputted comments or messages.
Regarding the input of these comments or messages, in JPA2004-302613, for example, an electronic settlement processing device is disclosed which realizes to smoothly execute the settlement process, by displaying a screen for urging a comment (such as a comment in a sticky note) input through a data processing screen after a previous input of password. Further, JPA2004-185160 discloses a work progress management system which realizes a smooth execution of the process, by providing an input column for comments from a boss, in a data processing screen after a previous input of password. JPA2010-277476 discloses a health guidance system which realizes a smooth execution of the health guidance, by enabling an input of a participant comment for participant ID and an input of a guide comment for guide ID, in a data processing screen after a previous input of password. Further, JPA2010-092185 discloses a network relay device which realizes management of user information by receiving previously registered user ID/password information as a message from a server, and displaying it on a screen. Furthermore, JPA2006-189542 discloses a print production system which is configured to enable a comment input as a data at the time of order processing on a print order terminal.

Information input display device and control program thereof

KONICA MINOLTA BUSINESS TECHNOLOGIES, INC.


Aromatic dicyanate compounds which comprise aliphatic moieties having at least about six carbon atoms and resins and thermoset products based on these compounds.

1. Field of the Invention
The present invention relates generally to aromatic dicyanate compounds which comprise aliphatic moieties having at least about six carbon atoms and to resins and thermoset products based on these compounds.
2. Discussion of Background Information
The performance requirements for thermosetting resins used in electrical applications continue to escalate. In particular, high frequency electronics have become more commonplace with advances in computer, communications, and wireless technologies. In view thereof, there is a need for resins which show reduced dielectric constants and dissipation factors as well as enhanced thermal resistance.
Aromatic cyanate compounds have been used in electronics applications for many years. The most common cyanate, bisphenol A dicyanate of the following formula:
can be prepared by reaction of bisphenol A (isopropylidene diphenol) with a cyanogen halide, for example, cyanogen bromide, in the presence of an acid acceptor, for example, triethylamine. Another known aromatic dicyanate compound is the dicyanate of cyclohexanone bisphenol. See, e.g., EP 612 783, the entire disclosure whereof is expressly incorporated by reference herein.

Aromatic dicyanate compounds with high aliphatic carbon content


A data storage system using flash storage maintains a status indicator corresponding to data written into the flash storage. The status indictor of the data indicates whether a disruption, such as a power disruption or a device disconnection, occurred when the data was being written into the flash storage. The data storage system determines whether the data may be corrupted based on one or more of the status indictors. The data storage system may make this determination at a selected time or after a power-up of the data storage system. If the data is determined to possibly be corrupted, the data storage system may optionally discard the corrupted data from the flash storage or flag the corrupted data for future removal.

1. Field of Invention
The present invention generally relates to computer memory and storage. More particularly, the present invention relates to a system and method of detecting and reducing data corruption after a power disruption occurs in a storage device.
2. Description of Related Art
An electronic or computing device may include flash storage for storing data. Although the flash storage retains data after the electronic device is turned off, the electronic device is generally sensitive to power disruptions during normal operation. Such power disruptions may be caused by several factors such as, for example, a result of battery discharge, power drop-off, power fluctuation, disconnection from or poor connection with a host device, interference, failure of a component or connection, or the like. Data written into the flash storage during power disruption is susceptible to corruption particularly if the power disruption occurs during the writing of data.
In light of the above, a need exists for a system and method to detect and reduce data corruption caused by a power disruption occurring in a storage device. Additionally, there exists a need for removing the corrupted data to increase storage space for subsequent or future use in the operation of the storage device.

System and method for detecting and reducing data corruption in a storage device


Salt-resistant Bacillus subtilis var. chungkookjang, accession no. KCTC 0697BP, separated from “chungkookjang” a traditional Korean fermented soy bean paste and its poly-gamma-glutamic acid (or poly-gamma-glutamate, g-PGA), an edible, soluble, anionic, and biodegradable high molecular-weight polymer. Bacillus subtilis var. chungkookjang produces g-PGA with a higher molecular weight than other extracellular g-PGAs derived from general Bacillus sp. strains and can be utilized for the development of high value-added products, such as cosmetics, absorption agents, and biodegradable plastic materials.

1. Technical Field
The present invention relates to the salt-resistant Bacillus subtilis var. chungkookjang, accession number KCTC 0697 BP, derived from "chungkookjang", a traditional Korean fermented soybean food, and to the poly-gamma-glutamic acid (or poly-gamma-glutamate, hereinafter referred to as γ-PGA) produced from said strain, which is an edible, soluble, anionic, and biodegradable polymer. In particular, the present invention relates to a novel Bacillus subtilis strain that produces an extracellular γ-PGA from an enzyme complex comprised of (1) D-amino acid aminotransferase EC 184.108.40.206, hereinafter referred to as "D-AAT", which transfers the amino group of D-amino acids into keto acid, (2) glutamate racemase EC 18.104.22.168, hereinafter referred to as "GluRA", and alanine recemase, hereinafter referred to as "AlaRA", which catalyze the creation of isomers from alanine and glutamate, and (3) γ-PGA synthetase and γ-PGA produced from said Bacillus sp. strain.
As illustrated in FIG. 1, many enzymes participate in the synthesis of the γ-PGA.
2. Related Art
γ-PGA is a mucous polymer substance consisting of χ-glutamyl conjugated D, L-glutamate and is produced from Bacillus sp. strains separated from traditional fermented soybean foods, such as "chungkookjang" from Korea, "natto" from Japan, and "kinema" from Nepal. The γ-PGA produced from such Bacillus sp. strain is an edible, soluble, anionic, and biodegradable polymer (molecular weight: 100˜2,000 kDa), which can be applied as an absorption agent, hygroscopic agent, raw material for cosmetics, and in the manufacture naturally degradable plastic through the synthesis of ester derivatives.
Recently, many studies have been focused on the production and application of γ-PGA, especially in advanced countries. Thus far, researchers have actively attempted to develop materials to replace non-degradable polymers and produce heat-resistant plastic through ester reactions, soluble fibers, and membranes etc. In addition, the physical changes of γ-PGA caused by γ-irradiation have also been studied, along with the development and industrialization of hydrogels using bridge adhesives. For example, the composition of γ-PGA, the effects of Mn ions affecting the production of γ-PGA, uses for soluble polymers degraded by ultrasonication and low soluble plastic through the synthesis of ester derivatives (Biosci. Biotechnol. Biochem., 60(8): 1239–1242, 1996), and the production of γ-PGA in Bacillus subtilis and calcium dissolving agents as healthy food for treating osteoporosis (Japanese Laid-open Patent No. Hei. 6-32742) have all been reported. Moreover, the reduction of water contamination based on decreasing the phosphate content in water systems (European Patent No. 838160), a high ratio for making a gel through irradiation, hygienic products, including diapers prepared using a biodegradable adsorptive resin with a water-absorbing property, food, application in the horticultural industry (Japanese Laid-open Patent No. Hei. 10-251402), and it practical use (Japanese Laid-open Patent No. Hei. 7-300522, Japanese Laid-open Patent No. Hei. 6-322358) have also been disclosed. Furthermore, the uses of γ-PGA as a solidified biodegradable fiber or film and film-forming agent through dissolution, precipitation, and drying (Japanese Laid-open Patent No. Hei. 7-138364, and Japanese Laid-open Patent No. Hei. 5-117388), polymers for a drug carrier (Japanese Laid-open Patent No. Hei. 6-92870, Japanese Laid-open Patent No. Hei. 6-256220) have been reported.
Meanwhile, Korean studies, including the efficient production of γ-PGA (Korean Patent Application No. 1997-3404; Korean Patent Application No. 1997-67605) and the improvement of its physical properties have also been performed. While, Pacific Inc., a cosmetic company of Korea, produced γ-PGA from a Bacillus subtilis natto strain and used it as a raw material for cosmetics and other practical uses.


Spacer fluids comprising a dispersant selected from the group consisting of water soluble polymers comprising allyloxybenzene sulfonate or allyloxybenzene phosphonate polymerized with at least one of acrylic acid, acrylamides, alkyl acrylamides, maleic anhydride, itaconic acid, sulfonated or phosphonated styrene, sulfonated or phosphonated vinyl toluene, sulfonated or phosphonated isobutylene, acrylamidopropane sulfonate or acrylamidopropanephosphonate, vinyl alcohol, sulfonated or phosphonated propene and alkali metal, alkaline earth metal and ammonium salts thereof and water with optional additional components such as surfactants, viscosifiers and wetting materials to form a rheologically compatible spacer fluid for use between a drilling fluid and a cement slurry and a method for using such spacer fluids to displace drilling fluids from a wellbore space with a cement slurry.

1. Field of the Invention
This invention relates to spacer fluids which are useful in displacing a first drilling fluid from a wellbore space with a second incompatible fluid.
2. Description of the Prior Art
In rotary drilling of wells a drilling fluid, sometimes referred to as a drilling mud, is circulated downwardly through a pipe, sometimes referred to as a drill string, and back up the annulus between the drill string, and the inside of the wellbore. Drilling fluid performs various functions such as cooling the drill bit, maintaining the desired pressure in the well, carrying drill cuttings upwardly through the annulus between the drill string and the wellbore face and the like as well known to those skilled in the art. The drilling fluid can contain many different chemicals but will most often contain a viscosifier such as bentonite. When a casing or liner is to be cemented into the wellbore, any drilling fluid and remnants of the viscosifier present in the wellbore are preferably removed to aid the bonding of the cement between the casing or liner and the wellbore. In removing this drilling fluid from the wellbore and to clean the annulus, a wash or spacer fluid can be introduced ahead of a cement slurry.
Spacer fluids are conventionally used in cementing operations relating to well completion as follows. Drilling fluids and cement slurries are typically chemically incompatible fluids which undergo severe gelation or flocculation if allowed to come into contact. Thus the drilling fluid must be removed from the wellbore annulus immediately prior to cement placement in the annulus. Spacer fluids are pumped between the drilling fluid and the cement slurry to form a buffer between the drilling fluid and the cement slurry, clean the annulus and prevent the drilling fluid and the cement slurry from coming into contact.
Spacer fluids should possess certain rheological tendencies which assist in granular solids removal and which encourage removal of the drilling fluid filter cake from the walls of the well. A common cause of failure in primary cementing is the incomplete displacement of drilling fluids which results in the development of mud filled channels in the cement. These mud filled channels may open during well production permitting vertical migration of oil and gas behind the casing.
Conventional spacer fluids are typically composed of an aqueous base fluid and a weighting agent. The weighting agent is included in the composition to increase the density of the spacer fluid to a desired value and to increase the erosion effect of the spacer fluid on the filter cake clinging to the walls of the well.
The fundamental properties of the aqueous base spacer fluid are typically particle stability and suspension (anti-settling properties), fluid-loss control, favorable rheology, and compatibility with drilling fluids and cement slurries. These properties are directly related to the composition of the spacer fluid.
Consequently a conventional spacer base fluid may include one or more of an anti-settling agent, a fluid-loss controlling agent, a dispersing agent, and a surfactant for obtaining a water wetted surface to aid in cement bonding. The final composition of conventional spacer fluids is typically obtained by adding a weighting agent to the aqueous base spacer fluid to achieve a desired fluid density.
The anti-settling agent and fluid-loss controlling agent may comprise a single component of the composition or may comprise a plurality of components of the composition. The component agents typically are soluble or dispersible in water. Dependent upon the water available at the site and in the geological strata encountered in the wellbore, the aqueous base spacer fluid typically includes fresh water, sea water, brine or an aqueous composition containing one or more dissolved salts such as sodium chloride, potassium chloride, magnesium chloride and calcium chloride. It is preferred that the spacer fluid retain its above mentioned fundamental properties at all possible salt concentrations. Spacer fluids are conventionally used over a wide temperature range from the surface temperature to the bottom hole circulating temperature in a wellbore. The bottom hole circulating temperature may be 200.degree. C. or higher in the case of certain geothermal wells. The term "anti-settling properties" refers to the capacity of the spacer fluid to keep the weighting agent particles in stable suspension throughout the cementing operation which may typically last from about 1 to about 4 hours or longer. A spacer fluid is considered to have good fluid loss control properties if the fluid loss measured according to API specification 10, Appendix F is less than 100 milliliters/30 minutes and excellent if the fluid loss is less than 50 milliliters/30 minutes. Favorable rheology for a spacer fluid requires that the fluid has minimum friction pressure while maintaining adequate suspension of solids. Since the spacer fluid is to be pumped between the drilling fluid and the cement slurry for removing and replacing the drilling fluid in the well annulus, it is very important the spacer fluid be as compatible as possible with both the drilling fluid and the cement slurry.
The compatibility of a spacer fluid with a drilling fluid and a cement slurry is determined in the laboratory by studying the viscosity of binary or ternary mixtures of spacer fluid with the drilling fluid and/or cement slurry varying over the range of 0 to 100 percent by volume for each component of the mixture. Such compatibility in the past has been difficult to obtain primarily because the drilling fluid and the cement slurry are incompatible fluids.
The compatibility of the spacer fluid with the drilling fluid and the cement slurry is considered to be excellent if the viscosity of a mixture of the spacer fluid and the drilling fluid or the cement slurry at a given shear rate and temperature is equal to or less than the viscosity of the more viscous component of the mixture at the same shear rate and temperature. Likewise, the viscosity of a mixture of all three components is considered to excellent if it is less than or equal to the viscosity of the most viscous component at the same shear rate and temperature.
Conventional spacer fluid compositions do not usually demonstrate good compatibility with mixtures of drilling fluids and cement slurries while simultaneously possessing good rheological fluid loss control and anti-settling properties over the entire range of shear rates and temperatures normally encountered in oil field services.
Spacer fluids using sulfonated styrene-maleic anhydride copolymer (SSMA) have previously been used. Such spacer fluids are disclosed in U.S. Pat. No. 5,030,366 "Spacer Fluids" issued Jul. 9, 1991 to Wilson et al; U.S. Pat. No. 5,113,943 "Spacer Fluids" issued May 19, 1992 to Wilson et al; and U.S. Pat. No. 5,292,367 "Dispersant Compositions for Subterranean Well Drilling and Completion", issued Mar. 8, 1994 to Bloys et al. These patents disclose spacer fluids containing dispersing materials which have many of the desired properties of spacer fluids. These patents are hereby incorporated in their entirety by reference.
The preferred dispersants disclosed in these patents are sulfonated styrene-maleic anhydride copolymer (SSMA) and sulfonated vinyl toluene-maleic anhydride copolymer (SVT-MA).
Unfortunately, SSMA and SVT-MA have not always been commercially available in sufficient quantities for oil field operations. As a result, it has been difficult to obtain sufficient quantities of SSMA and SVT-MA to satisfy the demand for dispersants in spacer fluid compositions. Accordingly, a continuing search has been directed to the discovery of additional dispersant materials which can be used to produce effective spacer fluids. As previously noted drilling fluids and cement slurries are incompatible fluids and few dispersant materials are effective to disperse mixtures of the two.

Method and spacer fluid composition for displacing drilling fluid from a wellbore


A method for coating cloth especially fiberglass sheets with a resin and resulting structure is provided. The coating is performed in two steps. In the first step, essentially all of the strands of the fiberglass are coated with the resin solvent mixture as well as most of the interstices or openings, although some of the interstices or openings have holes where the coating does not completely fill in. This first coating is then partially cured to the extent that it will not redissolve in a second coating of the same resin solution. The coated fiberglass with partially cured resin thereon is then given a second coating of the same resin mixture which coats the first coating and fills in any holes in the first coating. This second coating is then partially cured, which advances the cure of the first coating and results in an impregnated fiberglass cloth structure for use as sticker sheets. This substantially reduces pinholing.

Resin-impregnated fiberglass sheets are commonly used in the formation of printed circuit boards. The fiberglass cloth is typically impregnated with the selected thermoset resin which is then partially cured and the impregnated cloth sheared to form what are known as sticker or prepreg sheets. In order to enhance the adhesion of the resin to the fiberglass, often a coupling agent, such as a silane, is coated onto the surface of the fiberglass prior to impregnation. The prepreg sheets are then laid up with sheets of metal such as copper or copper-invar-copper (CIC) and laminated with heat and pressure to fully cure the laid-up laminate with the metal sheets defining ground, power and signal planes. One of the desirable characteristics of the resin-impregnated fiberglass sheets is that the resin-impregnation must cover the fibers of the fiberglass and must be able to be partially cured to a non-tacky state wherein the sheets can be handled for the lamination process. This is often referred to as a B-stage, a cure state which allows the sheets to be sufficiently self-supporting to be laid up as a laminate, but not advanced enough in the state of cure that they are rigid or non-flowable when heated, and they can be further cured to a final cure with heat and pressure to form a laminate structure as is well known in the art. As indicated above, this lamination process normally includes the lamination of one or more sheets of metal, such as copper, CIC or other metal, to provide necessary ground planes, power planes and signal planes buried within the laminated circuit board. Also in conventional practice, openings are formed, either by drilling or other means, through the fully cured laminates which form the openings for vias or plated through holes where the connections can be made from one surface of the circuit board to the other and to the various internal planes within the laminate as required.
A conventional technique of forming the resin-impregnated fiberglass sheets is to provide a coil of the fiberglass material and unwind the fiberglass material from the coil and continuously pass it through a tank containing the solution of the desired resin in a solvent, and then pass the coated or impregnated material through a treater tower wherein heat is applied to drive off the solvent and to partially cure the resin material by initiating cross-linking and then coiling the partially-cured or B staged material into a coil. Thereafter, the partially-cured material is uncoiled and cut into sheets of the desired length. These sheets, known as prepreg sheets, are then used in the lamination process described above.
This prepreg material has long been used for manufacturing circuit boards, however, more recently, the same prepreg material and same laminating techniques that have been used to form a circuit board have been used to form chip carriers. A chip carrier is basically a small-size version of a circuit board where the metallurgy and the lay out can be much finer than on a circuit board. Printed circuit board reliability tests are defined, e.g., in IPC specifications, whereas chip carrier tests are defined by JEDEC specifications which are derived for ceramic carriers and are more severe tests. In addition, because of the finer geometry of the metallurgy and the lay-out, chip carriers are more prone to failure from various failure mechanisms.
A particular defect that can occur is the formation of pin holes. A pin hole is an opening in the resin which impregnates the fiberglass. Most pin holes will fill in during lamination. However, a small number of pin holes may remain and become the source of defects. With pin holes, shorts can develop between adjacent power planes or power and ground planes, or whatever planes happen to be adjacent to each other. Potentially, these pin holes provide shorting paths that can be established and revealed under leakage tests and other high potential tests.
The cloth styles of intermediate thickness seem to be the most susceptible to pinholing, while very light weight and heavy weight cloths have a lower defect density. Thus, according to conventional prior art techniques, in order to reduce pin hole density in any given cloth, thinner, finer weave clothes are used. However, this has several drawbacks. First, thinner, finer weave clothes are more expensive than thicker, coarser weave clothes per unit area, and secondly, the thinner clothes in many instances may not provide the necessary thickness or dielectric separation between two adjacent planes, thus necessitating the use of two laminated superimposed clothes. The use of two clothes significantly reduces the possibility of pin hole defects establishing shorting paths since it is highly unlikely that two pin holes would be exactly aligned or closely enough aligned to provide such a path. Thus, if only one cloth of the pair has a pin hole, the strong probability is that this in itself will not be enough to cause the shortage since it is highly improbable that a pin hole in the other cloth will be aligned with the pin hole in the first cloth. When thicker clothes are used with a higher pin hole density, two clothes can also be used, but this significantly increases the thickness of the circuit board or chip carrier being formed which often is undesirable. Alternatively, to maintain the thickness, two sheets of thinner cloths have to be used to attain the required reliability.
Hence, it is an object of the present invention to provide a resin-impregnated cloth and a method of forming said cloth wherein the pin hole density is significantly reduced over cloths produced by prior art techniques.

Technique for forming resin-impregnated fiberglass sheets with improved resistance to pinholing

International Business Machines Corporation


A carpet stretcher is provided with the improvement of a stabilizing apparatus and method that attaches to a carpet stretching tool to prevent the carpet stretching tool and any of its additional stretcher tubes from bending or bowing when utilized to stretch carpeting during carpet installation. The stabilizing apparatus consists of a bar with appropriate means for attachment to a carpet stretcher.

This invention relates to a carpet stretcher stabilizing device and to a carpet stretcher comprising such a device.
During the installation of carpet, carpet stretchers are often used to stretch the carpet to eliminate creases and wrinkles. It is common to attach one end of the carpet to a floor mounted wood strip, called a "tack strip", having embedded upwardly extending pins or short nails for engaging the carpet. The carpet is then laid out to the opposite side of the room and the carpet installer then utilizes a carpet stretcher to stretch out the carpet prior to securing the carpet to the opposite side of the room with additional tack strips.
Carpet stretchers, examples of which are well known in the art, typically comprise a tail block for bearing up against a wall, a head that has teeth for gripping a carpet, a shaft or piston member fixed to the head, a cylinder member within which the shaft is slidable, a variable number of interconnectable tubes (based upon the size of the carpet to be stretched) for connecting the cylinder member to the tail block, and a power unit for sliding the head relative to the cylinder member and longitudinally to the stretcher tubes. The power unit typically comprises a lever which is pivoted on the head and attached to the cylinder member by a pivotal link so that the head is forced forward when the lever is depressed. In this manner, the stretcher tubes serve to transmit the forces in use to stretch the carpet.
A disadvantage of the known carpet stretchers is that the stretcher tubes are resiliently flexible and consequently tend to bow sideways during operation, as shown in FIG. 2, thereby reducing the effectiveness of the stretching operation and of the forces being transmitted to the carpet.
In has heretofore been proposed to immobilize the stretcher tubes by attaching to the stretcher tubes a carpet gripper which has teeth or the like for gripping the carpet surface or having an addition brace kit as describe in U.S. Pat. No. 4,815,708 issued to Samson on March 28th, 1989. Both proposals have the potential for damaging the carpet if there is any deflection of the stretcher tubes when in use. In addition, the second proposal can be costly and time consuming in applying the additional brace kits for use.
Accordingly, it is believed to be advantageous to provide a less costly means for better stabilizing the stretcher tubes of a carpet stretcher that does not have the potential for damaging the carpet being stretched.

Stabilizing device for a carpet stretcher


A double valve has two coils which can be piloted separately from each other and which each have a core. The coils are arranged in a common valve housing, and a flange housing is mounted to the valve housing. Two valve seats are arranged in the flange housing, and a diaphragm is associated with the two valve seats, with each coil being associated with one valve seat.

The invention relates to a solenoid valve that can switch a fluidic communication.
Such solenoid valves are known in different configurations. One example can be found in document DE 201 00 471 U1. It comprises an actuating drive having two coils which actuate a commutation rocker. The commutation rocker acts on a diaphragm which in turn can cooperate with two valve seats. The diaphragm simultaneously forms the separation between the actuating drive and the fluidic side of the valve.
Generally, attempts are made to configure such valves in an increasingly compact manner. However, any manufacturing tolerances have a more aggravating effect the more compact the valves are by design, because the actuating forces that are obtainable by the actuating drive of the valve (preferably a solenoid coil) are greatly reduced with an increasingly smaller constructional volume. At the same time, the manufacturing tolerances of the components can only be reduced with great expenditure. The fact that it is no longer possible to considerably reduce the required space for the fluidic and electrical connections further complicates the miniaturization.
The object of the invention consists in providing a compact solenoid valve.


A system and method for using double-evoked otoacoustic emission (2EOAE) signals to elicit an evoked response from the cochlea. A three sample stimulus includes a first signal, a time delayed second signal and the superposition of the first and second signals. The time delay is selected to be less than the maximum latency of the cochlear emission. Each of the three signals elicits a response from the cochlea that include a linear response. The linear response is eliminated by subtracting the response to the first and second individual signals from the response to the superposition signal. One class of signals arises when the time delayed signal is a scaled version of the first signal. The signals can include click signals, chirp signal and the like. Chirp signals can be used to mimic classical distortion product (DP) responses. The signals may be presented using a single acoustic source or separate acoustic sources. With the appropriate selection of time delays, the 3 signal stimulus can greatly reduce nonlinear response due to probe distortion. With two acoustic sources, probe distortion can be virtually eliminated. The system also includes a noise coherence measurement to determine the relative levels of system response caused by random noise as opposed to nonlinear response. A real-time artifact rejection technique also simplifies the collection of data.

Cochlear response measurements in the ear canal pre-date the discovery of otoacoustic emissions. The importance of measurements of the acoustic impedance of the ear from a location in the ear canal has been long known, beginning with measurements obtained in 1928 and described in "Measurement of the Acoustical Impedances of Human Ears," by W. West, Post Office Electrical Engineers Journal, 21:293-300, 1928. Subsequent research has led to techniques that provide information on the external, middle and inner ear. One such system, described in U.S. Pat. No. 3,294,193, issued 1966 to Zwislocki, describes an instrument that measures a response function of the ear.
A subset of this response function provides measurements of reflected energy from the cochlea, because the mid-frequency part of the resistive component of the middle ear impedance is mainly due to the cochlear resistance, as first obtained by measurements in cats and rabbits, as described in "An Experimental Study of the Acoustic Impedance of the Middle Ear and its Transmission Properties," A. Moller, Acta Oto-Laryngol., 60:129-149, 1965, and Auditory Physiology, A. Moller, Academic Press, New York, 1983.
Early research had established the cochlear origin of subharmonic distortion products recorded in ear-canal pressure response measurements, as described in "On the Generation of Odd-Fractional Subharmonics," P. Dallos, J. Acousi. Soc. Am., 40:1382-1391, 1966, and in The Auditory Periphery, P. Dallos, Academic Press, U.S.A., 1973. Dallos also commented on his early research into the source of acoustic emissions in Comment on `Observations on the Generator Mechanism of Stimulus Frequency Acoustic Emissions-Two Tone Suppression` (D. T. Kemp and R. Chum) in Psychophysical, Physiological and Behavioral Studies in Hearing, page 42, E. deBoer and M. A. Viergever, editors, Delft University Press, 1980.
Following this early work by Dallos, otoacoustic emissions (OAEs) were discovered by D. Kemp, described in "Stimulated Acoustic Emissions From Within the Human Auditory System," D. T. Kemp, J. Acoust. Soc. Am., 64:1386-1391, 1978. Kemp's discoveries initiated an active period of research continuing to the present on cochlear-based signals that are inferred from pressure measurements in the ear canal. Broadly speaking, OAEs are classified into spontaneous otoacoustic emissions (SOAE), which refer to cochlear-based responses in the ear canal in the absence of any external stimulus, and evoked otoacoustic emissions (EOAE), which arise in response to an acoustic stimulus delivered into the ear canal.
These evoked responses are categorized according to the type of stimulus. The stimulus-frequency otoacoustic emission (SFOAE) is obtained using a sinusoidal signal, as described in "Observations on the Generator Mechanism of Stimulus Frequency Acoustic Emissions-Two Tone Suppression," D. T. Kemp and R. Chum, in Psychophysical, Physiological and Behavioral Studies in Hearing, pages 34-41, E. deBoer and M. A. Viergever, editors, Delft University Press, 1980. The SFOAE is a low-level signal measured in the ear canal at the frequency of the sine tone, which is based upon the property that the evoked emission has a saturating nonlinearity as the stimulus level is increased.
Other types of stimulus signals include a click-evoked otoacoustic emission (CEOAE) response, described in "Stimulated Acoustic Emissions From Within the Human Auditory System," J. Acoust. Soc. Am., 64:1386-1391, 1978, U.K. Provisional Patent No. 5467/78, 1978 to D. T. Kemp, U.S. Pat. No. 4,374,526, issued Feb. 22, 1983 to Kemp ("Kemp (1983)"), and U.S. Pat. No. 4,884,447, issued Dec. 1, 1989 to Kemp ("Kemp (1989)"). These references describe a measurement that is the pressure response to the presentation of a single click (also termed pulse), or the differential pressure response pulse to the presentation of clicks delivered at two (or more) intensity levels. A click, or, equivalently, a pulse, is a wide-bandwidth, deterministic, short-duration signal. The duration is usually limited by the duration of the impulse response of the acoustic source transducer, since the electrical input signal to the source transducer is typically much shorter than this impulse response duration. The stimulus duration is typically 1-4 milliseconds (msec), whereas the overall duration of the CEOAE response is in the range of 10-40 msec. In the prior art of Kemp (1983), the duration of the CEOAE response is assumed to extend over a 20 msec interval, and to prevent overlapping of the responses from succeeding pulse stimuli, it is stated that the time interval between pulses should be at least 20 msec, corresponding to a presentation rate of 50 Hz. Time gating of the response is recommended to remove the initial 5 msec of the total response, which is not included in the definition of the OAE response, and this initial portion of the response is thus excluded from the definition of the CEOAE response.
Distortion product otoacoustic emissions (DPOAEs or DPs) are OAEs measured in response to a stimulus comprised of two continuous, sinusoidal tones with frequencies .function..sub.1 and .function..sub.2. Information from the DPOAE includes the frequencies at which there are significant intensity levels, for example, at the 2.function..sub.1 -.function..sub.2 DP site. The term "site" refers to the location in the cochlea that is believed to generate the evoked emission. The underlying cochlear mechanisms leading to latencies or time delays in CEOAE also produce latencies in the DPOAE responses, which can be measured in terms of the group delay, as can be appreciated by those skilled in the art, and interpreted to provide information on cochlear micromechanics. The term "latency" refers to the time delay in the evoked response to the stimulus, whereas the group delay is defined based upon the rate of change of the signal phase with frequency. To control for probe nonlinearity, it is typical to use two source probes. One probe outputs the sine tone at .function..sub.1, and the other probe outputs the sine tone at .function..sub.2. The use of two independent probes controls for the intermodulation distortion that would otherwise occur at sum and difference frequencies if a single probe were used.
As described in "A Review of Otoacoustic Emissions." R. Probst, B. L. Lonsbury-Martin, and G. K. Martin, J. Acoust. Soc. Am. 89:2027-2067, 1991, current research indicates that these various OAE measurements systems are providing information from a common physiological origin, involving cochlear micromechanics and the mechanisms underlying signal transduction in the cochlea. Thus, advances in EOAE measurement techniques are aimed at providing more accurate, or more comprehensive, data regarding these cochlear mechanisms.
More complex stimuli have been used to measure EOAEs, including tone bursts created using short-duration, rectangular-windowed sinusoids (other windows including Gaussian have been used). Time averaging of the evoked response with artifact rejection and noise rejection is recommended by Kemp et al. (1986). "Artifact rejection" in this prior art has been taken to include a differential subtraction of responses, so as to eliminate the linear response, as in Kemp (1989), including the use of time gating. "Noise rejection" in this prior art is when the sound pressure level (SPL) exceeds some threshold during the portion of the signal after the first 5 ms. This is taken as evidence of a noise source external to the cochlear response. Time averaging is effective at attenuating noise, but has no benefits for reducing the nonlinear response output by the probe that is synchronous with the stimulus presentation rate. Artifact rejection, as used in the present application, differs in meaning from that of Kemp (1989), and is defined below. This probe nonlinearity interacts with the middle ear response in the first few milliseconds after presentation of a click stimulus. Both the middle ear response and the probe nonlinearity are large during this time interval.
Different linear cancellation procedures have been utilized in an attempt to control for this probe nonlinearity. One approach measures two responses, a first response to the stimulus at one level and a second response to the same stimulus, but at some higher level, typically on the order of 6 decibels (dB) higher. The low-level response is boosted or amplified by the same difference in level (6 dB in this example), and subtracted from the high-level response. If the system were linear, then the result would be a null response. Thus, the measured response after subtraction is due to the EOAE response and the synchronous residual probe nonlinearity. The residual probe nonlinearity can be significant and contaminates the beginning of the EOAE response. To eliminate this initial contamination, the EOAE response is typically nulled over the first 2-5 msec. However, eliminating the beginning of the EOAE response results in the elimination of the high-frequency content of the EOAE which is characterized by short latencies in this range. Presently, no techniques exist for CEOAE or tone-burst EOAE systems to control for probe nonlinearity that are as effective as the two-source probe technique for the DPOAE measurements.
Another standard subtraction technique in CEOAE systems, discussed in Kemp (1989), uses a single probe to produce four stimuli. The first three stimuli are three identical clicks and the fourth stimuli is a fourth click, but with the opposite polarity and three times the amplitude of the first three identical stimuli. The responses are summed to produce a response which would be zero if the cochlear EOAE behaved as an ideal linear response. This subtraction of the linear response is the "artifact rejection" of Kemp et al. (1986). This is argued as reducing random noise, but the probe nonlinearity is not controlled, and is worse than the previously described technique since the relative gain between high and low-level clicks is larger, thereby producing greater amounts of probe distortion. The initial 5 msec of the CEOAE response is nulled to remove probe artifacts.
Each of the existing EOAE systems lacks the ability to easily measure a wideband response or suffers from the inability to control for probe nonlinearities. Therefore, it can be appreciated that there is a significant need for a system and method to measure stimuli to produce evoked emissions while controlling for nonlinearities without the use of time-gating. Moreover, present theories do not allow the interpretation of click-evoked OAE responses within the framework of a distortion product-evoked OAE response model, and vice versa. The present invention provides this and other advantages, as will be seen from the following discussion and accompanying figures.

System and method for the measurement of evoked otoacoustic emissions


A detector for an x-ray tomography apparatus has a plurality of detection elements arranged near an x-ray incident position in an array transverse to the slice direction. Each detection element is formed with a phosphorescent element for converting an incident radiation beam into light and a photoelectric conversion element for converting light from the phosphorescent element into an electrical signal. The phosphorescent element is shorter in the slice direction than the sensitive region of the photoelectric conversion element such that radiation reaching an edge area of the phosphorescent element can also be detected within a sensitive region of the photoelectric conversion element and generation of virtual and false images can be prevented.

This invention relates to a detector for use with an x-ray tomography apparatus such as an x-ray CT apparatus.
As shown in FIG. 4 as an example, an x-ray CT apparatus comprises an x-ray tube 31, a collimator 34 and a radiation detector 35 such that a fan-shaped x-ray beam 32 emitted from the x-ray tube 31 passes through a target body 33 to be examined and, after passing through the collimator 34, is detected by the radiation detector 35 having many detector elements arranged in an array. Explained more in detail, the radiation detector 35 may be a solid radiation detector formed as a one-dimensional array of combinations of a scintillator for converting radiation into light and a photoelectric converter element for converting light into an electrical signal. An array of 8 to 30 such combinations of a scintillator and a photoelectric converter forms a block, and the radiation detector 35 is formed with several of such detector blocks 36 disposed continuously as a part of a polygon on the circumference of a circle.
As shown in FIG. 5, each block of the radiation detector 35 has many radiation detector elements arranged in a channel direction (indicated by double-headed arrow), mutually separated by screening plates 45, each radiation detector element comprising a rectangularly elongated scintillator element 41 and a photoelectric element 43 such as a photodiode having the same width as the scintillator element 41, pasted to the bottom surface of the scintillator element 41 and disposed on a supporting member 44.
When the fan-shaped x-ray beam 32 emitted from the x-ray tube 31 reaches this radiation detector, the x-rays are converted into light by the scintillator elements 41, this light is then converted into electrical signals by the photoelectric conversion elements 43 such that data can be obtained both in the channel direction and in the slice direction (indicated by another double-headed arrow in FIG. 5). An image is formed on the basis of these data.
With modern x-ray CT devices, however, the sphere of the x-ray tube is large, and this makes the displacement of its focal point also large corresponding to temperature variations. If the focal position moves in the channel direction, its effects are negligible according to the prior art technology described above because there are many radiation detector elements arranged in this direction. If the movement is in the slice direction, say, from Focal Position A to Focal Position B shown in FIG. 5, however, the light-receiving position by the scintillator element changes from its center part to an edge part, and this affects the sensitivity of the detection signal.
As shown in FIG. 6, the sensitivity curve of a detection element is flat near the center but it is not flat but decreases as one moves in the slice direction and reaches an edge position. Thus, if the light-receiving position of each scintillator element moves from the center to an edge position, the sensitivity of the detection signals is adversely affected and the outputted signal is not accurate. This was a cause of the generation of virtual and false images.
Especially when data of a thick slice are to be obtained, the difference in sensitivity between the center and edge parts of the detection elements in the slice direction is large, and virtual and false images are likely to appear because each scintillator element must be used from one end part to the opposite end part in the slice direction.


In a recording apparatus, an input moving image signal and sound signal are separately encoded. The encoded moving image signal and sound signal are recorded on a recording medium. When a recording stop instruction is input, recording of the encoded moving image signal is stopped while recording of the encoded sound signal is continued until a predetermined period elapses from stop of recording of the encoded moving image signal.

Conventionally, apparatuses which encode a moving image signal and a sound signal and records them on a magnetic tape or plays back them.
Particularly, of apparatuses of this type, VTRs which record or play back a moving image signal and a sound signal in accordance with an encoding scheme called DV format are known as consumer appliances. In the DV format, a moving image signal is encoded in a frame, and a sound signal corresponding to the moving image signal is encoded by PCM (Pulse Code Modulation) and recorded on a recording medium. The video signal and sound signal, which are encoded by the DV format are synchronized. Hence, when signals recorded on a magnetic tape by continuous recording are played back, the continuity of moving images and sound is maintained.
In recent years, VTRs which record a moving image signal and a sound signal on a magnetic tape by MPEG (Moving Picture Experts Group) have also made their debuts. Even for such VTRs using MPEG, methods which allow seamless playback in continuous recording have been proposed and disclosed in, e.g., Japanese Patent Laid-Open No. 10-262211.
In recording a video signal and a sound signal compressed by MPEG on a recording medium, the video signal is encoded for each GOP (Group Of Pictures) including a predetermined number of frames including intra-frame encoded images of one frame. However, the sound signal is encoded for an arbitrary number of samples.
For this reason, the encoding unit of moving image signals does not coincide with that of sound signals. Hence, as shown in FIG. 8, when recording of moving image signals is stopped, a sound signal of a frame for which encoding is not ended yet is not recorded. In playback, sound signals at the continuous recording portion cannot keep the continuity so that a silent portion is generated. This may make seamless playback impossible.
When recording is done by MPEG, as shown in FIG. 9, decoding of the start frame after continuous recording may be delayed due to a factor such as the VBV (Video Buffering Verifier) buffer control amount or GOP structure, and the image of the frame before the continuous recording may be played back in a freeze state. At this time, sound of the frame after the continuous recording is decoded and played back so that the moving image signal and sound signal, which are played back, do not match.


According to one embodiment, a video processing apparatus includes a video data output device which outputs a data packet signal obtained by packetizing a data enable signal and a synchronization packet signal obtained by packetizing a synchronization signal, a transmission device which transmits the data packet signal and the synchronization packet signal, the data packet signal being delayed by a first delay amount and the synchronization packet signal being delayed by a second delay amount, and a timing controller which generates the data enable signal and the synchronization signal so as to set a pulse of the synchronization signal within a blanking period of the data enable signal based on the data packet signal and the synchronization packet signal.

In general, a video data output device directly transmits a packet signal based on video data to a display device. An I/F format conversion device or a video data processing device is sometimes arranged between the video data output device and the display device. In any case, a signal is transmitted to the display device at a stable timing complying with constraints of the display device.
Various packet signals are transmitted not only from a video data output device to a display device but also from other devices (hardware) different from the video data output device to other devices different from the display device. In this case, packet signals are transmitted via a common transmission device. The transmission device arbitrates between packet signals to determine from which device transmission is performed to which device.
At this time, packet signals are delayed by the transmission device by inconstant delay amounts (different delay amounts). For this reason, the packet signals based on video data from the video output device are transmitted to the display device upon being delayed by different delay amounts. There is therefore a possibility that video data may become a signal which does not meet the constraints of the display device (which is not accepted by the display device).


A device and method for sensing a change in differential pressure within a fluid flow is disclosed. In one embodiment, a differential pressure is induced in a flow of fluid through a conduit between first and second axially spaced locations. One side of a diaphragm, piston, or other differential pressure movably responsive member in a differential pressure housing is exposed to the pressure of the flow at the first location, while its opposite side is exposed to the the pressure of the flow at the second location. A extension or the like engages the diaphragm on its high pressure side and passes out through a wall of the differential pressure housing where it is mechanically interconnected with a switch, which in turn is operatively interconnected with a valve in the conduit. Sufficient movement of the diaphragm due to certain change in the differential pressure between the two sides of the diaphragm will physically move the extension which is engaged therewith, which in turn will physically move the switch to a position where a signal is provided to valve to adjust the flow characteristics through the conduit. These movements may be used to identify an underflow condition where the flow rate between the first and second locations is less than a desired flow rate, and/or to identify an overflow condition where the flow rate between the two locations is more than desired.

Many fluid-based applications use some type of device to identify the existence of a leak somewhere in the relevant system. One such application is in the water distribution system for a house or other building structure (e.g., offices). Another involves fuel storage or distribution systems where at least part of the system is stored underground. Yet another application is irrigation systems where relatively large quantities of water are distributed to crops or the like. There are of course many other fluid-based applications where leak detection is desirable or required.
In some cases, the leak detection system exists principally because leaks cannot be readily detected. This is the case in underground fluid flow/storage applications where a visual inspection is not possible, as well as in those cases where a visual inspection is possible but where small leak rates are not readily visually discernible but are in fact important to identify. Other leak detection systems exist so that appropriate actions may be more readily initiated when the leak is detected. Leak detection systems can of course be designed with both of these parameters in mind.
Some leak detection systems are designed to detect a flow condition when there should be no flow. Other leak detection systems are available to detect a leak in a fluid system in which there is a fluid flow. Flow meters are used in both of these instances. Generally, the flow meter will sense an increase in the flow rate (whether from a zero flow condition to at least a certain flow condition, or from a predetermined/preset flow condition to an increased flow condition). Sensing of the increase in the flow rate will typically cause an electrical signal to be sent to some type of control circuit, and this control circuit will in turn send an electrical signal to a valve which will then shut to terminate the flow.
Existing leak detection systems suffer from a number of disadvantages. Some systems are quite complex which obviously increases the cost of the system. For instance, many leak detection systems require their own power source and controller. Increased complexity of the leak detection system can also make integration of the leak detection system into the fluid system more complicated than desired. Other leak detection systems are not what may be termed "generic." That is, some leak detection systems are designed for use with only certain flow rates or a very limited range of flow rates, and may not be appropriate or at least may not be readily adaptable for other applications having significantly different flow rates. Finally, some leak detection systems have an automatic reset feature. Although this may be appropriate for some applications, it is not necessarily appropriate for others.

Differential pressure detection system for signaling electrically-activated valve


A new computer-implemented method for determination of a financial index, namely, implied volatility for American options. The method involves the division of the period until option expiration into a series of sub-periods, and calculation of a node vega, the node vega being the exact derivative of the option price with respect to the volatility at the end of at least one of said subperiods.

Implied volatility is a quantity related to the price of a traded financial option to buy ("call" option) or to sell ("put" option) a particular asset. Specifically, implied volatility represents the market's estimate of the future price volatility of the underlying asset. According to results of Black and Scholes, the market price of an option depends solely on the asset's future price volatility, the current price of the underlying asset, the risk-free interest rate, the dividend yield (if any) from the underlying asset, the exercise price of the option, and the time to expiration.
In the case of "European" options (options which can only be exercised at expiration), Black and Scholes present a formula for the calculation of the fair market price of the option given its volatility and other inputs. Subsequent researchers showed how this formula could be inverted, essentially solving for the volatility using the other inputs and the current market price of the option. This value is referred to as implied volatility, and is used by options traders as an indication of the relative value of an option, in much the same way that yield serves as a measure of the relative value of a bond. An equivalent Black-Scholes type formula does not exist for American options.
Option pricing and implied volatility are known in the art, and further discussion of them provided in the following publications, all of which are fully incorporated herein by reference: Black, F. and M. Scholes, 1973, "The Pricing of Options and Corporate Liabilities", Journal of Political Economy, 81, 637-654; Cox, J. C., S. A. Ross, and M. Rubinstein, 1979, "Option Pricing: A Simplified Approach", Journal of Financial Economics, 7, 229-263; Cox, J. C., and M. Rubinstein, 1985, "Options Markets", Prentice-Hall, Englewood Cliffs, N.J.; and Latane, H., and R. Rendleman, Jr., 1976, "Standard Deviation of Stock Price Ratios Implied in Option Prices", Journal of Finance, 31, 369-382.

Method of determining implied volatility for American options