A vehicle display apparatus includes a plurality of display devices that superpose and display a plurality of pieces of information by displaying information at each position of a plurality of different positions in a predetermined direction towards the front of a vehicle that can be viewed by a driver of the vehicle, and includes as at least one of the plurality of display devices, an attention attracting display device that displays as the information, attention attracting information on the nearest side to the driver in the predetermined direction.

1. Field of the Invention
The present invention relates to a vehicle display apparatus.
2. Description of Related Art
Conventionally, a night vision system that detects a pedestrian from image data taken by a camera and displays image data in which the pedestrian is surrounded by a rectangular frame on a display device has been known (for example, refer to Japanese Unexamined Patent Application, First Publication No. 2010-88045).


A turbine blade comprises an airfoil/shank having a shank region and an airfoil region extending upwardly therefrom and two dovetail/platforms bonded thereto. The first dovetail/platform has a first dovetail region bonded to a first side of the shank region of the airfoil/shank, with a first platform region extending outwardly from the first dovetail region. The second dovetail/platform has a second dovetail region bonded to a second side of the shank region of the airfoil/shank and a second platform region extending outwardly from the second dovetail region in a direction generally opposite to that of the first platform region.

This invention relates to gas turbine engines, and, more particularly, to the structure and fabrication of turbine blades used in such engines.
In a gas turbine engine such as used by jet aircraft, air is drawn into the front of the engine and compressed by a shaft-mounted compressor. The compressed air is mixed with fuel, and the mixture is burned in a combustor. The resulting hot exhaust gases are passed through a turbine that causes the compressor shaft to turn, and then out the rear of the engine to provide forward thrust.
The turbine of the gas turbine engine includes stationary turbine vanes that redirect the generally axial flow of hot exhaust gas so that it has a small sideways momentum component. Turbine blades are mounted on a turbine disk that in turn is mounted on a rotating shaft, usually the same shaft that turns the compressor. The impact of the hot exhaust gas on the turbine blades forces the turbine blades to rotate circumferentially. The turbine disk turns, driving the compressor through the rotation of the shaft.
The turbine blades and turbine vanes are key components of the gas turbine engine. They must operate in a high-temperature oxidizing environment, which may carry salt and other corrosive and erosive agents. The turbine blades operate under high stresses created by centrifugal forces as the turbine disk turns. The ability of the turbine blades and turbine vanes to operate in these conditions is essential to the efficient operation of the gas turbine engine, because engine efficiency increases with increasing temperature of the hot exhaust gas that enters the turbine section of the engine. The turbine blades of the high pressure section and the forward stages of the low pressure section of the turbine section experience the highest temperatures and operating stresses. In most cases, the performance of these turbine blades limits the performance of the engine. The present invention is of most direct benefit to these turbine blades, but is applicable to the other turbine blades in the turbine section as well.
Because of the critical importance of the turbine blades to the operation of the gas turbine engine, a great deal of attention has been directed to their improvement. Turbine blades are typically made of complex alloys of nickel, cobalt, and other elements. Alloys of this type have been developed specifically for this application. The turbine blades may be made as single crystals or directionally aligned polycrystals, to take advantage of the mechanical properties of particular crystallographic directions. The turbine blades are often coated with thermal barrier coating systems to increase the permissible temperature of the hot exhaust gas. The turbine blades also may have cooling channels therethrough so that cooling air can be passed through the interior of the blades to reduce the blade temperature.
Although turbine blades must be engineered to operate in these highly adverse environments, they must also be manufactured in a reasonably economical manner. A typical commercial gas turbine engine may contain 80 turbine blades or more, and the cost of the turbine blades can add a substantial amount to the initial cost of the engine and its repair costs as the turbine blades are replaced during the operating life of the engine. Thus, there is a continuing need for improved, reduced cost manufacturing techniques to fabricate complex gas turbine blades from superalloy materials and with the required crystallographic structures and orientations.


In a magnetic recording medium to detect tracking error signals optically where an optical head and a magnetic head scan different tracks, two signals having phases different by .pi./2 are generated and added or subtracted. By changing the amplitude of the two signals with a changeable gain amplifying means, a phase of a tracking error signal is changed so that the servo operation is conducted at the middle of the amplitude of the tracking error signal to keep the magnetic head on track.

1. Field of the Invention
The present invention relates to information recording media which comprise a high density information recording means such as an optical information recording medium including an optical disk or a magnetic information recording medium including a fixed magnetic disk or a floppy disk, a tracking error signal detection apparatus for the information recording media, and an information recording apparatus which can precisely record, reproduce and erase information on the information recording media using the tracking error signal detection apparatus, and also relates to methods of adjusting an information recording apparatus.
2. Disclosure of the Prior Art
A track pitch of a conventional magnetic recording media on which information is recorded, such as a floppy disk. Therefore, the track pitch is much wider than that of an optical disk, which is about 1.6 .mu.m. Accordingly, a rough track location using a mechanical method such as a stepping motor has been sufficient. However, in order to realize a magnetic recording medium having a larger capacity, a track pitch from several .mu.m to several tens .mu.m is required. In this case, a precise track location becomes necessary.
FIG. 1 shows a configuration of a conventional magnetic recording apparatus which detects a tracking error signal by using light. In FIG. 1, a linearly polarized divergent beam 70 radiated from a semiconductor laser light source 10 is converted to a parallel beam by a collimator 20 and the parallel beam enters a polarizing beam splitter 30. All the parallel beam 70 entering the polarizing beam splitter 30 passes through the polarizing beam splitter 30 and enters a 1/4 wavelength plate 31. The parallel beam 70 is converted to a circularly polarized beam by passing through the 1/4 wavelength plate 31 and is focused on a magnetic recording medium 40 by an object lens 21.
FIG. 2 shows the relationship between the magnetic recording medium 40 and the focused light beam 70. The magnetic recording medium 40 has tracks Tn-1, Tn, Tn+1 . . . , which include the area on which information is recorded or reproduced by a magnetic head 99 with a certain pitch pt (approximately 20 .mu.m). Further, discrete guiding grooves Gn-1, Gn, Gn+1 . . . , which enable the optical detection of a signal synchronizing a tracking error signal and which enables rotations of the magnetic recording medium 40, are formed in the middle of adjacent tracks.
The beam 70 reflected and diffracted by the magnetic recording medium 40 passes through the object lens 21 again, and enters the 1/4 wavelength plate 31. By passing through the 1/4 wavelength plate 31 again, the beam 70 is converted to a linearly polarized beam having a 90.degree. phase change of the light source 10. All the beam passing through the 1/4 wavelength plate 31 is reflected by the polarizing beam splitter 30 and enters a photodetector 50. The incident light beam is converted into an electric signal by the photodetector 50 and inputted to a signal processing portion 80.
As illustrated in FIG. 1, the photodetector 50 has two light sensing portions 501, 502. Signals outputted from the light sensing portions 501, 502 are converted to voltage signals by current-voltage (I-V) converting portions 851, 852 respectively, and inputted to a differential operation part 871. The differential operation part 871 subtracts the two voltage signals outputted from the I-V converting portions 851, 852.
When a beam 70 from the optical system has a displacement x from the center of a guiding groove such as Gn on a magnetic recording medium 40, voltage signals v21, v22 outputted from the I-V converting portions 851, 852 become sine waves having opposite phases which can be approximately represented by the below mentioned formulae (1) and (2). The signals v2l, v22 can be illustrated as FIG. 3(a) and (b). EQU v21=-A.multidot.sin (2.pi.x/pt)+B (1) EQU v22=A.multidot.sin (2.pi.x/pt)+B (2)
In the formulae (1) and (2), A is an amplitude and B is a DC component.
A signal v23 outputted from the I-V converting portion 871 can be represented by the below mentioned formula (3) and outputted from a terminal 801 as the tracking error signal. EQU v23=2.multidot.A.multidot.sin (2.pi.x/pt) (3)
The signal v23 can be illustrated as FIG. 3(c). The tracking error signal v23 outputted from the terminal 801 is inputted to a driving portion 90 to adjust relative positions of a magnetic recording medium 40 and a base 95 including a tracking error signal detection optical system 100 and a magnetic head 99 for recording and reproducing information so as to form a desired track on the magnetic recording medium 40. The tracking error signal detection method is known as the push pull method.
(First Problem)
In a conventional magnetic recording apparatus using a magnetic head 99 for recording and reproducing information, and an optical system 100 for the detection of a tracking error signal, a distance d between a point S1 at which the magnetic head 99 contacts a magnetic recording medium 40 and a focal point S2 of a beam 70 from the optical system needs to be at least several hundred .mu.m to several mm. That is, the point S1 at which the magnetic head 99 contacts the magnetic recording medium 40 and the focal point S2 of the beam 70 scan different tracks on the magnetic recording medium 40.
In assembling a magnetic recording apparatus, the distance d is adjusted so as to have the working point of the tracking servo at the midpoint S3 of the signal amplitude of the tracking error signal v23 as illustrated in FIG. 3(c) when the point S1 is on a track of the magnetic recording medium 40. However, temperature or humidity change causes expansion or contraction of the magnetic recording medium 40 and the track pitch pt changes accordingly. Therefore, in the tracking operation at the point S3 using the tracking error signal v23 obtained from the optical system 100, the point S1 becomes off track and thereby drastically deteriorates the information reproduction characteristics.
In this case, for example, if a point S4 is the working point on the tracking error signal when the point S1 is on the track, a tracking servo can be enabled by applying an offset voltage to the tracking servo. However, the dynamic range of the orientation illustrated by the arrow D1 lowers and thereby deteriorate the followability in the case disturbance generates. Further, as the point S4 moves farther from the point S3, the servo gain of the tracking operation lowers. When the point S4 eventually reaches the point S5, a new problem occurs that the servo gain of the tracking becomes 0 thereby completely losing the tracking servo.
On the other hand, in an optical disk apparatus where the beam used to detect tracking error signals and the beam used to record information on the information recording medium are identical, a configuration forming a track on or between the guiding grooves so as to record and reproduce information with a further high density is proposed. However, in this configuration, when the relationship pt>.lambda./NA is satisfied where .lambda. is a wavelength of the beam radiated from the light source, NA is an numerical aperture of the object lens at the information recording medium side, and pt is a cycle of marks or guiding grooves formed on the information recording medium to enable the detection of the tracking error signals, a problem similar to the above mentioned problem occurs when the predetermined angle between the beam focused by the object lens and the information recording medium can not be sustained. Specific examples include the case having a wavelength .lambda. of 650 nm, a numerical aperture NA of 0.6, a cycle pt of marks or guiding grooves of 1.48 .mu.m, and a substrate thickness for the information recording medium of 0.6 mm.
(Second Problem)
Dusts or flaws on the magnetic recording medium 40 change the reflection ratio of the magnetic recording medium 40 and the intensity of a light beam 70 reflected thereby accordingly. In this case, a problem occurs in that an offset occurs in the tracking error signal, and thus the magnetic head 99 can not be controlled on a desired track of the magnetic recording medium 99.
(Third Problem)
Moreover, as in the above mentioned prior art, if a stepping motor is used in the tracking driving portion 90 for a magnetic recording medium having a track pitch of several .mu.m to several tens .mu.m for seeking tracking error signals using a light beam, an off track generates which depends on the step width of the stepping motor. By making the step width narrower to reduce the off track amount, a problem occurs in that the time for detecting tracks becomes longer. These two problems can be solved by the use of a DC motor instead of a stepping motor in the tracking driving system. However, since mechanical positioning can not be controlled if a DC motor is employed in a tracking driving portion 90, a new problem occurs in that information can not be recorded or reproduced in a magnetic recording medium having a track pitch of 188 .mu.m, which is now widely used.
(Fourth Problem)
Further, an optically optimum value for a numerical aperture NA of the object lens 21 for a magnetic recording medium having a track pitch of 50 .mu.m is about 0.017. However, when an angular dislocation .theta. exists between the beam 70 focused by the object lens 21 and the magnetic recording medium 40, the beam 70 reflected by the magnetic recording medium 40 can not enter the aperture. Therefore a problem occurs in that the quantity of the light beam introduced to the photodetector 50 decreases and thus the tracking operation becomes unstable. The relationship between a performance function Ev with respect to the angular dislocation .theta. (Ev=0.5.multidot.tan(2.multidot..theta.)/NA) and a quantity of light I of the beam 70 introduced by the photodetector 50 is shown in FIG. 4. With a numerical aperture NA for the object lens 21 of 0.017, the angular dislocation .theta. is 0.97 when the quantity of light I of the beam 70 on the photodetector 50 is 0, namely, the performance function Ev is 1. In this case, the tracking error signal can not be obtained at all.

Information recording medium and tracking error signal detection apparatus and magnetic recording apparatus and method of adjusting the magnetic recording apparatus

Matsushita Electric Industrial Co., Ltd.


A parallel operation system of transmission amplifiers enable the parallel running by the two distortion compensation amplifiers using the digital pre-distorter system and to provide a parallel operation system of the transmission amplifiers that makes it possible to switch to respective single running easily. The parallel operation system includes first and second transmission amplifiers which receive common input signals for outputting amplified signals from respective ones; and a coupling unit which combines outputs of the first and second transmission amplifiers, to provide as its output; the first and second transmission amplifiers each having a main amplifier; and a modulation unit disposed on the input side of the main amplifier; wherein the output of one of the modulation units included in the first and second transmission amplifiers is fed in common to the main amplifiers included in the first and second transmission amplifiers.

1. Field of the Invention
The present invention relates generally to a parallel operation system of transmission amplifiers, and more particularly to transmission amplifier parallel operation system adapted for a mobile radio base station.
2. Description of the Related Art
With mobile radio communication terminals prevailing in recent years and furthermore demands for high-speed data services rising, increasing the transmission output of base stations has become a greater problem. To increase the transmission output of base stations, high-powered transmission amplifiers are needed and to increase the electric power of transmission amplifiers it is generally necessary to enlarge heat dissipation fins. Therefore it is unavoidable that the configuration of transmission amplifiers becomes big.
On the other hand, when transmission amplifiers are made to perform amplification functions in the nonlinear range of amplification characteristics to obtain high-efficient output, nonlinear distortions arise. To compensate it, feed forward system is generally adopted.
As disclosed in Japan Patent Pub. No. Hei7-77330, for example, the transmission amplifiers adopting the feed forward system are configured such that distortion components are found from the difference between main amplifiers' inputs and outputs, the found distortion components are amplified to the level equivalent to the outputs of the main amplifiers and then added to the outputs of the above main amplifiers, and the found distortion components are canceled. Amplifier outputs with compensated distortions can thus be obtained.
However, the configuration of the transmission amplifiers adopting the feed forward system needs amplifiers for distortion components that amplify the distortion components to the level equivalent to the outputs of the main amplifiers. A delay circuit is also needed to adjust the timing to add the outputs of the amplifiers for distortion components and those of the main amplifiers.
Furthermore, there is a digital pre-distorter system as a method to compensate the nonlinear distortions of high-powered transmission amplifiers. The principle of the digital pre-distorter system is that characteristic components opposite to the distortion characteristics of the amplifiers are prepared on the input sides of the amplifiers through digital processing and these are added beforehand on the input sides of the amplifiers through digital processing. As a result, the distortion components created by the amplifiers themselves are canceled and the amplified outputs free from any distortions can be obtained from the amplifiers.
A configuration example of amplifiers using the digital pre-distorter system has been proposed before by the present applicant (see Japan Patent Laid-open Pub. No. Hei9-69733).
The amplifiers using the digital pre-distorter system don't need the amplifiers for distortion components, compared with the configuration that adopts the feed forward system. Therefore the amplifiers can be constituted easily because there is no need of adjustment to time the outputs of the amplifiers for distortion components and those of the main amplifiers.
On the other hand, mobile radio base stations adopt a redundancy configuration of transmission amplifiers to secure the reliability of devices. By way of example, FIG. 1 shows a redundancy configuration of the transmission amplifiers that adopt the feed forward system.
In FIG. 1, two amplifiers 1 and 2, each of which has distortion compensating function, adopt the above feed forward system and are parallel connected for the redundancy configuration. In normal times, transmission signals are modulated in a modulation unit 3 and its output is two branched in a branching unit 4.
The two branched outputs from the modulation unit 3 are inputted into the transmission amplifiers 1 and 2 respectively and amplified to the respective predetermined levels. The outputs of the transmission amplifiers 1 and 2 are again connected and outputted by a coupling unit 5. Through this in normal times, it is possible to obtain the output power for which the output powers of the transmission amplifiers 1 and 2 are combineed in the coupling unit 5.
Also in the configuration shown in FIG. 1, when either of the systems of the transmission amplifiers 1 and 2 is in trouble, the output power is halved but it is possible to continuously keep the output.
Furthermore, in the configuration shown in FIG. 1, when the output is two branched by the branching unit 4 in normal times, the level is halved (−3 dB). But the output of the modulation unit 3 is distributed in common phase in the branching unit 4 and the respective outputs of the transmission amplifiers 1 and 2 are connected in common phase in the coupling unit 5. Through this in the coupling unit 5, the loss in the branching unit 4 at the time of branching can be canceled. Therefore it is possible to use the outputs of the transmission amplifiers 1 and 2 efficiently also in the parallel configuration.
In FIG. 1, one modulation unit 3 is shown. But for the parallel configuration, two modulation units are prepared and either of the outputs is inputted into the branching unit 4 for redundancy.
As explained earlier, compared with the configuration of the distortion compensation amplifiers of the feed forward system, it seems advantageous to employ the transmission amplifiers using the digital pre-distorter system also in parallel running for the redundancy configuration because the configuration is easy in that neither the amplifiers for the distortion components nor the delay circuit and the like are necessary.
On the basis of such an idea, FIG. 2 shows an assumed configuration example when the transmission amplifiers using the digital pre-distorter system are parallel run. In the case of the transmission amplifiers using the digital pre-distorter system, because modulation units 3-1 and 3-2 where transmission signals are branched and inputted are arranged on preceding stages of the main amplifiers 10-1 and 10-2, the transmission amplifiers 1 and 2 that are parallel run and distortion compensated have the following problems.
That is, the modulation units 3-1 and 3-2 are respectively constituted, including digital pre-distorters (DPDs) 30-1 and 30-2, quadrature modulators (QMODs) 31-1 and 31-2, up-converters (UCONVs) 32-1 and 32-2 and down-converters (DCONVs) 33-1 and 33-2.
In FIG. 2, the up-converters (UCONVs) 32-1 and 32-2 have the function to change frequencies by multiplying carrier frequencies from local oscillators 320-1 and 320-2 in multipliers 321-1 and 321-2. Filters 322-1 and 322-2 are roll off filters to limit bands.
As described above, the two distortion compensation amplifiers 1 and 2 that are parallel run retain local oscillators 320-1 and 320-2 individually to change the frequencies in the respective up-converters (UCONVs) 32-1 and 32-2.
However, the phase difference of the output carriers is not compensated concerning the two local oscillators 320-1 and 320-2. Therefore it is difficult to connect in common phase the outputs of the two transmission amplifiers 1 and 2 in the coupling unit 5. So it is not ensured to compensate in the coupling unit 5 the loss when transmission signals are branch inputted into the transmission amplifiers 1 and 2.
When the transmission amplifiers are redundancy configured to secure the reliability of the device and the digital pre-distorter system is adopted for the transmission amplifiers due to the above reasons, the direct application corresponding to the feed forward system in FIG. 1 was difficult.

Parallel operation system of transmission amplifier


An integrated circuit transistor and a method for making the same are provided. The transistor is resistant to junction shorts due to the overetch of local interconnect trenches. The transistor includes a source/drain region with a first junction and a second junction that is located deeper than the first junction in the portion of the active area susceptible to the overetch junction short phenomena. The second junction is established by ion implantation through a mask that is patterned to create an opening corresponding to the intersection of the layouts of the active area and the local interconnect trench. Using this method, the second junction is only established where needed to prevent shorting and does not impede transistor performance.

1. Field of the Invention
This invention relates generally to semiconductor processing, and more particularly, to an integrated circuit that has an overetch resistant local interconnect structure, and a method for making the same.
2. Description of the Related Art
Modern integrated circuits routinely contain millions of individual transistors and other electronic components. Most of the interconnections for the numerous individual transistors in a modern integrated circuit are provided via one or more metallization layers that serve as global interconnect levels. Each metallization layer is ordinarily deposited on the substrate of the integrated circuit as a single continuous layer that is thereafter patterned lithographically and etched to remove metal from areas where metal lines are not required.
In addition to the one or more metallization layers, modern integrated circuits also incorporate numerous routing-restricted interconnect levels commonly known as local interconnect ("LI"). LIs are used for short metallization runs such as those that locally interconnect gates and drains in NMOS and CMOS circuits and those that connect a given metallization layer to a particular structure in the integrated circuit.
A method frequently employed to form LI structures involves a damascene process in which the substrate containing the integrated circuit is coated with a layer of dielectric material that is lithographically patterned and etched to form trenches in the dielectric layer where the LI structures will be deposited. For LI structures interconnecting transistor components, the trenches must be formed in close proximity to the components of the transistors. For example, an LI structure intended to interconnect the source or drain of a transistor requires a trench to be formed in the overlying dielectric layer that extends down to the source or drain. If the LI structure is designed to interconnect with an overlying structure, such as a metallization layer, and if alignment of the photolithographic process used to pattern the trench is perfect or nearly perfect, the trench will be patterned and etched only over the source or drain. However, LI structures are frequently used to interconnect adjacent circuit structures. Such laterally routed LI structures must pass over at least one border between the active area of the strapped transistor and its surrounding isolation trench. In addition, photolithographic processes seldom achieve perfect alignment. Lateral routing and/or misalignment result in the frequent patterning and etching of LI trenches over not only the targeted transistor structure, such as the source or drain, but also over the isolation structures that border the transistor. Since the isolation structures are frequently composed of the same or a similar type of dielectric material that is being etched to form the LI trench, the etching process may attack the isolation structures surrounding the transistor and form voids that extend to the active area of the transistor. When the LI material is ultimately deposited in the trench, conducting material fills the void and shorts the junction. The result is lower yields.
In addition to lowering yields, the overetch problem may lead to wasted electrical testing steps. The problem stems from the fact that the shorted junctions may not occur uniformly across the surface of a given wafer. As a consequence, shorted junctions may arise in the operational transistors, but not in the test structures in the wafer. The defects in the operational transistors may not be detected during the initial electrical characterization tests which are normally performed only on the test structures. Such defects may only be detected during subsequent probe testing of the operational circuits on the wafer. The result is wasted processing time.
In conventional LI processing, control of the overetch problem is attempted through manipulation of the etching process. The disadvantage of this approach is that precise control of the etching process is difficult to achieve. This is due, in large part, to the fact that the design rules for a conventional LI trench etching process are based upon an anticipated average thickness for the dielectric layer, and any underlying layers, such as TiSi.sub.2 and a Si.sub.3 N.sub.4 or oxynitride etch stop layer. In practice, however, the actual thicknesses of these layers may be less than the anticipated norm. As a consequence the etch process may remove these layers and attack the underlying isolation structure before the etch cycle is completed.
Furthermore, there may be variations in the composition of the dielectric and underlying TiSi.sub.2 and Si.sub.3 N.sub.4 layers that may enable the etchant species to attack certain areas more aggressively than others and lead to overetch. The overetch problem is, as noted above, exacerbated by the fact that the dielectric layer and the underlying isolation structures are composed of the same or a related dielectric material. Consequently, once the etch stop layer is compromised, the etchant gases will readily attack the isolation structure.
The present invention is directed to overcoming or reducing one or more of the foregoing disadvantages.

Transistor formation with local interconnect overetch immunity


A system for adjusting the white balance of a projector type color display device is shown. The color display device includes three single color cathode ray tubes from which single color beams are projected onto a screen to form a colored image on the screen. The white balance adjusting system comprises a first device for feeding one of the three cathode ray tubes with all white signal to cause the same to project a single color image on the screen; a second device for detecting a luminance value of the single color image on the screen; a third device for deriving luminance values of the other single color images from the detected luminance value; and a fourth device for controlling the selected cathode ray tube in such a manner that the derived luminance values are put in a tolerance which is provided for dealing with a noise of the second device.

1. Field of the Invention
The present invention relates to a system and a method for adjusting the white balance of a projector type color display device.
2. Description of the Prior art
In color projectors (viz., projector type display devices), "white balance adjustment" is usually carried out at the time when the projectors are still in a manufacturing line and/or they are brought to a user's setting place. As is known, by properly adjusting the white balance of the color projector, the color image on the screen can have a natural color tone. However, in the color projectors of a type wherein images on display surfaces of three (viz., Red, Green and Blue) color display TV tubes are projected onto a screen to form a colored image thereon, the white or color balance of the projector is easily out of tune due to complicated arrangement of the three display TV tubes. Thus, in the color projectors of such type, the white balance adjustment is always necessary when the setting place and setting orientation of the projector change. Furthermore, such white balance adjustment becomes necessary when the projectors are used for a long time.
Hitherto, the white balance adjustment at the manufacturing line has been made by using color sensors. That is, the color sensors are manually attached to the display faces of the three display tubes for sensing the colors displayed on the display faces. All white signals (such as 5IRE signal and 100IRE signal) are fed to each display tube as an external signal, and the white balance adjustment of the color projector is carried out with reference to the information signals issued from the color sensors. One of the methods of this type is described in Japanese Patent First Provisional Publication 3-236699.
The white balance adjustment at the user side has been made by using a colorimeter and a color-difference meter. That is, the adjustment has been made manually by an inspector who compares, with his or her eyes, the color image on the screen and the reference color data provided by the colorimeter and the color difference meter.
However, it is difficult or at least troublesome to adjust the white balance by using the above-mentioned conventional adjusting methods. In fact, attaching and detaching the color sensors to and from the display tubes on the manufacturing line are troublesome. This becomes much more severe when a plurality of stackable color display devices, which are used for forming a so-called "multiscreen", are subjected to the white balance adjustment. Furthermore, the white balance adjustment by using the colorimeter and the color-difference meter requires a great deal of skill.

System and method for adjusting white balance of projector type color display device


Fibers comprising a first thermoplastic composition having a softening temperature up to 120° C and a curable resin. Also disclosed are compositions comprising a plurality of fibers, with some of the fibers comprising a first thermoplastic composition having a softening temperature up to 120° C and some of the fibers comprising a curable resin. The fibers have an aspect ratio of at least 2:1 and a maximum cross-sectional dimension up to 60 micrometers. Fluid compositions containing the fibers and methods of contacting a subterranean formation using the fibers are also disclosed.

Various multi-component fibers are known. Examples include fibers that have a low temperature melting or softening sheath covering a higher melting core. Multi-component structures may be useful, for example, for fiber bonding, wherein the sheath, for example, when melted or softened serves as a bonding agent for the core.
In the oil and gas industry, production of oil and/or gas is sometimes increased using hydraulic fracturing, which involves injecting a viscous fracturing fluid or a foam at high pressure into a subterranean well to form fractures. As the fracture is formed, a slurry of a particulate material, referred to as a "propping agent" or "proppant", in the fluid or foam is carried into the fracture. Upon release of the pressure, the proppants form a pack which serves to hold open the fractures, thus providing a highly conductive channel in the formation.
The efficacy of the hydraulic fracturing-fracture propping approach may be hindered by undesired transport of the proppant during clean-up operations or during production from the well. The transport of proppants, which is also known as flow-back, may restrict flow in the well bore, increase fluid friction, and contaminate produced fluids and therefore is undesirable.
Several different approaches have been used to address the problem of flow-back. Some fibers have been used in combination with proppants for flow-back control, and the modification of proppant geometry including the aspect ratio and particle size distribution has been investigated. Resin coated proppants have also been used. Resin coated proppants are expected to adhere to each other downhole to form an integrated proppant block. Different types of resin coatings have been used, including thermosetting resins (e.g., an epoxy or phenolic) and thermoplastic elastomers (e.g., acrylic resins). A disadvantage of resin coated proppants for proppant flow-back control is the potential premature curing of the proppant, and their required compatibility with the components of hydraulic fracture fluid (e.g., breakers) provides challenges.
Despite the advances in the technologies for flow-back control, there is a need for additional flow-back control options.


A system, program product, and method for monitoring and managing a plurality of marine riser assets is provided. The system can include one or more floating vessels each carrying a shipboard computer, a plurality of riser assets to be tracked and monitored, a riser asset identification sensor positioned to identify select riser assets being deployed to establish a riser string, one or more riser joint instrument modules positioned along the length of the riser string to provide riser asset load data, a centralized data warehouse to store riser asset identification and loading data for riser assets deployed at multiple remote vessel locations, and a riser lifecycle management server and riser lifecycle management program product adapted to monitor riser asset conditions, issue automated service alerts based on actual use information, maintain routine and non-routine maintenance records, manipulate and categorize riser assets, and automatically generate an accurate riser system configuration as was actually deployed for any particular drilling/completion operation.

1. Field of the Invention
The present invention relates to riser management systems. More particularly, the present invention relates to a system, program product, and related methods for monitoring and managing a plurality of marine riser assets.
2. Description of Related Art
A problem presented by offshore hydrocarbon drilling and producing operations conducted from a floating platform or vessel is the need to establish a sealed fluid pathway between each borehole or well at the ocean floor and the work deck of the vessel at the ocean surface. This sealed fluid pathway is typically provided by a drilling riser system. Drilling risers, which are utilized for offshore drilling, extend from the drilling rig to a blowout preventer (BOP). Similarly, production risers extend from and provide communication between a subsea wellhead system and the floating vessel.
A typical marine drilling riser permits passage of drill pipe which is used for pumping lubricating mud down the well during drilling operations, return of drilling mud that has been pumped through the drill pipe into the main tube of the riser, and any associated drill cuttings, and provides a connection of the drilling vessel to the well above the subsea BOP stack. The drilling riser can be disconnected from the well above the BOP stack, allowing the drilling vessel to retrieve the riser and temporarily move from the drill site should the need arise (i.e., during a hurricane event, or a malfunction). The BOP stack, having remained on the wellhead, provides for containment of a live well while the vessel is not on location. Upon return, the vessel can deploy the riser, reconnect to the BOP stack, and reestablish hydrocarbon communication with the well.
The marine drilling riser also permits control of the well should the BOP stack have to be functioned. This is typically associated with drilling through a zone with geological fluid pressure that is substantially higher than that which the drilling mud can contain. During such events, the BOP is functioned, and well control is re-established by pumping an appropriate density mud thought the kill line and eventually circulating it back to the surface via the choke line. The marine drilling riser also permits improvement of mud circulation velocity. When needed, this is accomplished by pumping additional mud through the booster line and injecting it into the riser bore at the BOP stack. This increases the volume of mud in the riser; improving the return speed. The marine drilling riser further permits delivery of hydraulic fluid to the BOP stack control system. Such fluid is supplied through a dedicated external hydraulic line.
The drilling riser, for example, is typically installed directly from a drilling derrick on the platform of the vessel by connecting a series of riser joints connected together. After connecting the riser to the subsea wellhead on the seabed, the riser is tensioned by buoyancy cans or deck mounted tensioner systems. The riser is projected up through an opening, referred to as a moon pool in the vessel, to working equipment and connections proximate an operational floor on the vessel. In drilling operations, the drill string extends through a drilling riser, with the drilling riser serving to protect the drill string and to provide a return pathway outside the drill string for drilling fluids. Similarly, in producing operations, a production riser is used to provide a pathway for the transmission of oil and gas to the work deck.
Basic components of a riser system typically include, from the mud line and extending to the surface: a hydraulic wellhead connector which permits connection to a subsea wellhead; a SOP stack used for well control; a lower marine riser package which permits disconnect and reconnect of the marine riser at the BOP stack; multiple marine riser joints normally in the form of bare and buoyant joints each outfitted with a choke and kill line, a booster line, and a hydraulic line; and a termination joint which is a special riser joint where external lines are terminated and diverted to the appropriate facility on the vessel. For example, the kill line is terminated and connected to the mud pump via a high pressure flexible line. The components also include a tension ring which provides for the interface of the marine riser to the hydro-pneumatic riser tensioner designed to provide lateral load resistance while providing a somewhat constant vertical tension; and a telescopic joint typically made of two sliding pipes sealed together via an elastomer primarily used is to decouple the motion of the vessel, while permitting the riser tensioner system to apply a near constant tension on the marine riser. The components also include a diverter used for diverting of the unwanted gas in the marine riser; a gimbal located on the rig floor used during running and retrieval of the marine riser to dampen the pitch motion of the vessel, and a marine drilling riser spider used during the mating of each riser section to the next.
Other more specialized riser equipment includes a fill-up valve designed to prevent collapse of the riser pipe due to the differential pressure between the inside of the riser pipe and the surrounding water, an instrument riser joint typically used to monitor the tension and bending due to environmental conditions which allows for adjustment in top tension and vessel positioning, vortex suppression equipment which help suppress vortex induced vibrations typically found in conditions of high current and long riser length, and an emergency riser release which provides a specialized riser release system to prevent catastrophic failure typically found in conditions where incorrect vessel positioning or extreme environmental conditions may occur.
During a typical field installation, the marine riser components are individually lifted from the deck, connected to each other at the riser spider, and run down. Riser joints, which comprise the major length of the riser string, are fabricated in lengths ranging from 50′ to 90′. During the running procedure, the portion of the riser string that is fully made up is landed on the riser spider. The next riser joint is then picked up and placed just over the spider, immediately above the suspended riser string. The two riser sections are then joined by means of a mechanical connector, etc. The most common type for a riser joint provides a bolted flange configuration.
Marine risers are subjected to impact loads as well as unexpected side loads, which can damage fragile electronics. Marine risers are also subjected to environmental loads as well as vessel-induced loads. The associated environmental parameters include, among other things, wave height and period, water depth, current, wind, and tides. In the subsea environment, hydrostatic pressure can reach 4,500 psi in current deepwater areas, and probably will reach 5,500 psi within a few years, and the seawater temperature can be as cold as 30° F. The high temperature of the drilling mud could also impact electronic and sensor equipment, particularly electronic equipment attached directly to the riser pipe (joint) body. The vessel-induced loads include the applied top tension necessary to maintain the optimum shape for a riser string, and those imparted by the marine riser string due to motion of the vessel as it is subjected to wave, wind, and current loading. The most critical component of environmental loads is generally the current load directly imparted on the riser string. The current loads typically vary with the water depth, but are generally much stronger near the surface.
Some locations around the world, such as the West of the Shetlands and the Gulf of Mexico, offer unique challenges associated with strong currents. In the Gulf of Mexico, for example, an environmental event establishes a seasonal "Loop Current", which moves in a circular pattern reaching a diameter a hundred miles or more. Such loop currents impart exceptionally high environmental loads on a riser, often for weeks at a time. High current loading can result in shedding of vortices past a marine riser string, which, if coupled with unfavorable riser damping, can result in violent motion of a marine riser string, typically in a cross flow direction. This is commonly referred to as "Vortex Induced Vibration" or "VIV." The large amplitude of the riser motion during a VIV event can result in elevated stress levels in the riser string, which, in turn, dramatically reduces the fatigue life of the individual riser joints. A single fatigue event can potentially result in the catastrophic failure of the marine riser string. Worse yet, a VIV event can take place in higher modes, for example, such as where only a small portion of the riser string, possibly hundreds of feet below the water surface, is excited and experiences VIV. Recognized by the Applicant is that in such a scenario, an observer on the vessel, looking down at the visible portions of the riser string, would see no evidence of this VIV event. Fortunately, catastrophic failure of risers has been few and far between.
A goal or series of goals for both drilling and production risers is to manage stresses and loading of individual riser sections to provide for fatigue analysis, and thus, allow the operator to formulate an enhanced inspection, maintenance, and riser joint rotation program. If a single riser joint in a riser string fails or otherwise exceeds an operational constraint resulting in a requirement for immediate maintenance, an entire riser string may have to be retrieved and rerun. In deepwater operations, it might take two or more days to run or retrieve a marine riser. Given the approximate rate of well over $500,000 per day for a 5th generation drilling vessel, such a scenario would cost the operator over a million dollars just to establish communication with the subsea well. This point should illustrate the importance of saving time during the running and retrieving of the riser. It should also illustrate the importance of lost time, and the associated cost, resulting from a riser component failure. There have been, however, until now, no effective systems or methods of efficiently tracking riser assets, efficiently tracking cumulative stress or other loading on each riser asset, or accurately determining or differentiating expected stress levels between vessels or fields in order to properly forecast required maintenance.
Recognized by the Applicant, therefore, is the need for a system, program product, and methods of managing riser assets, especially riser joints, which can provide asset managers a list of all the riser assets allocated to each specific vessel and provide a further breakdown of those assets that are currently deployed, are on deck, or are out for maintenance, along with the expected return date; a list of upcoming scheduled maintenance events; an estimate of the amount of operational life being expended by a particular riser asset; and an estimate of the total amount of cumulative operational life used by a particular riser asset, along with the details of the most damaging events (i.e., a certain hurricane event). Also recognized is the need for a system, program product, and methods of managing riser assets, especially riser joints, which include a central database that can be used by field and maintenance personnel to maintain and communicate critical riser asset information, and that can enhance both routine maintenance scheduling and the process of identifying a requirement for an unscheduled maintenance event. Also recognized is the need for such a system, program product, and methods which can provide detailed information on riser maintenance history and critical/relevant manufacturing information, and provide a capability to properly track riser assets so that they can be moved from one vessel to another with their history intact.
Further recognized is the need for such a system, program product, and methods which can provide a time stamp for each riser deployment to permit the determination of where, in the water column, each riser asset was located for any particular drilling or production campaign, which can, in turn, provide the user with information to reconstruct a riser string configuration of any particular deployment to thereby analyze riser asset performance and preferred positioning. Also recognized is the need for a system, program product, and methods which can allow a user to optimally position a specific riser joint at a specific position (depth) along the riser string, for example, based on an amount of operational life available (remaining), for example, in order to match a riser joints having a high amount of operational life remaining with riser string depths expected to encounter a higher stress.
Still further, recognized is the need for a system, program product, and methods of managing riser assets, especially riser joints, which include provisions for controlling a riser tensioning system to extend the operational life of the various riser assets and to control riser performance such as, for example, when encountering vortex induced vibration.

Riser lifecycle management system, program product, and related methods


The present invention provides a new process for preparation of imidazo-tetrazine class of chemical entity useful as anticancer agent. The present invention provides a commercially and economically viable process for preparation of Temozolomide of formula (VI).

Temozolomide, also known as 3-methyl-8-aminocarbonyl-imidazo[5,1-d]-1,2,3,5-tetrazin-4(3H)-one is a known antitumor drug, and is represented by formula VI:

It is indicated for treating patients with malignant glioma such as cancer, refractory anaplastic, astrocytoma, i.e. patient at first relapse who have experienced disease progression in malignant glioma, glioblastoma multiform and anaplastic astrocytoma, on a drug containing a nitrosourea and procarbazine. It is sold in the US market as oral capsules dosage forms containing 5 mg, 20 mg, 100 mg, 140 mg, 180 mg or 250 mg as Temodar® by Schering Corporation.
J. Med. Chem. 1984, 27, 196-201 describes a process wherein 5-amino-1H-imidazole-4-carboxamide is converted into 5-diazo-1H-imidazole-4-carboxamide, which is then cyclised with methylisocyanate in dichloromethane to provide Temozolomide.
This process requires isolation of the unstable and potentially dangerous 5-diazo-1H-imidazole-4-carboxamide. Methyl isocyanate is another difficult reagent to handle and transport, especially on the industrial scale. Further, the cyclization using methylisocyanate also requires a long reaction time with large number of impurities formation.
J. Org. Chem. 1997, 62, 7288-7294 describes a process for preparing Temozolomide wherein the last step of diazotization results equi-formation of aza-hypoxanthine dye and temozolomide, resulting in poor yield. This literature does not provide the complete details of the experimental procedure for work up.
Edward et al in U.S. Pat. No. 5,260,291 first generically discloses the product Temozolomide and its derivatives as per Scheme-1
In this patent, the process results in the poor yield due to the decomposition of Temozolomide to impurities like compound of formula 5-(3-methyltriazen-1-yl) imidazole-4-carboxamide (VII)
and 5-amino-1H-imidazole-4-carboxamide. Further the reactant methyl isocyanate is not safe to handle in the industrial/lab purpose.
Shen-Chun et al in U.S. Pat. No. 6,844,434 describes a process involving the use of a bulky protecting group on nitrogen of the primary amide for cyclisation in presence of LiCl to minimize the undesired cyclization product. After cyclization the protecting group has to be removed, which makes the process more laborious with more number of steps as depicted in the below mentioned Scheme-2:

Shen-Chun et al in U.S. Pat. No. 7,087,751 generically discloses another process for making Temozolomide and its analogs as per Scheme-3:

Synthesis of the Temozolomide described in this patent consists of a high number of synthetic steps and the involvement of a dangerous reactant such as t-butylisocyanate resulting the process to be non-amenable to scale up for industrial synthesis.
Raghavendracharyulu venkata et al in US20070225496 discloses the synthesis of Temozolomide as per scheme 4:

The above described process involves use of methyl isocyanate, which is highly flammable and difficult to handle on large scales that make the process unsuitable for industrial synthesis. In addition to this, isolation of Temozolomide from the reaction mixture requires addition of large amount of ethyl acetate followed by addition of hexane and again ethyl acetate to isolate the compound.
Bhirud et al in WO20100140168 discloses a process for preparation of Temozolomide as per Scheme 5:

The process involves the necessarily use of alcoholic solvent, which was found to result in loss of intermediate yield besides more time consuming steps owing to impurities formation leading to an intermediate of purity about 90-95% (area % by HPLC). The process also involves use of organic acid as acetic acid as necessary requirement, however, inventors observed that said reaction was surprisingly found to run smooth while using hydrochloric acid or like mineral acids. A reproduction of the industrially amenable process was also found difficult owing to inconsistencies/variability in the steps due to impurities formation. Hence, inventors of the present application observed that many improvements are possible in the process to make the process not only economically viable & robust, but also easily amenable to scale up with green chemistry compliance.
Turchetta et al in U.S. Pat. No. 8,232,392 discloses the synthesis of Temozolomide by the addition of 5-aminoimidazole-4-carboxamide and N-succinimidyl-N′-methyl carbamate and further the cyclization of caramoyl-5-amino imidazole-4-carboxamide.

The process involves purification of Temozolomide by means of Column chromatography on adsorbent polymeric resin, which is considered to be tedious and more time consuming process and hence industrially not applicable.
S L Pathi et al in U.S. Pat. No. 8,258,294 discloses the synthesis of Temozolomide as per Scheme-7:

This process involves the counter current continuous liquid-liquid extraction technique to isolate Temozolomide.
Patent application describes two methods for the extraction of Temozolomide.
In first method, Temozolomide is extracted from the reaction mixture by counter current extraction using continuous liquid-liquid extractor. Although the use of counter-current extraction reduces the usage of solvent during extraction but isolation requires a specific apparatus. The use of tedious step of counter current extraction and need of the specific apparatus makes the process unsuitable from the industrial point of view.
In the second method, Temozolomide is extracted using conventional techniques which requires large volumes of solvent such as dichloromethane (1000 times) with respect to the starting imidazole intermediate to obtain reasonable amount of crude Temozolomide which needs further two or three times crystallization to achieve desired purity. The process is not industrially viable and product cannot be extracted effectively due to handling problem of huge volumes of solvent.
Other patent application viz; WO2018112589, WO2018122724, IN162/MUM/2012 and CN103626772 also discloses the processes for making Temozolomide, however they result in one or the other difficulties of industrial up scalability more particularly the poor yields, large number of impurities formation, multiple steps of isolation, size of equipment etc. Space has to be taken in to account, because use of such large reactors (for distillation) and specific apparatus for the extraction like liquid-liquid extractor, as reported in prior art, and handling of hazardous reagents resulting in the need of developing an industrial viable process.
Due to the existing difficulties in the prior art disclosed process, there still exist need to develop a process for preparing Temozolomide which is more convenient, especially on an industrial scale, to provide improved yields and purity.
Thus, present invention fulfils the need of the art and provides an improved and industrially applicable process for the preparation of Temozolomide.

Process for preparing highly pure temozolomide

Abstract: Present invention also relates to an intermediate compound of formula (III) and its preparation useful in the process for preparing Temozolomide.


In a power transmission, which adjusts and transmits the rotational output of an engine by the engagement control of a starting clutch 5, the rotational speed Ne and the suction negative pressure Pb of the engine are measured while the starting clutch is being actuated from a disengaged condition to an engaged condition with the engine being operated under a constant operational condition. An engagement-control value is calculated for the starting clutch when there is a change in the rotational speed and the suction negative pressure being measured, and the engagement-control value calculated is stored as an initial control value for starting an engaging action of the starting clutch. This initial control value is used for controlling the engagement of the starting clutch.

This application claims the priority of Japanese Patent Application No. 2001-375644 filed on Dec. 10, 2001 which is incorporated herein by reference.
The present invention relates to a method for controlling the engagement of frictionally engaging elements provided in a power transmission, through which engagement control, the rotational output of an engine is transmitted to wheels with some adjustment.
Generally, an automobile includes a construction that transmits the driving force of an engine through a power transmission to wheels for driving the vehicle body, and for controlling this power transmission, a plurality of frictionally engaging elements such as friction clutches are typically incorporated in the transmission. For optimizing the engagement characteristic of the friction clutches in engagement control, it is important to monitor accurately the engagement control value at the time of the initiation of engagement action. Generally, the power transmissions used in an automobile is equipped with hydraulically actuated friction clutches. In this case, hydraulic actuation pressures are evacuated from the clutches completely for disengagement. Therefore, when any friction clutch is to be engaged, the friction clutch must be at first cleared of the ineffective or invalid part of the stroke of the clutch piston before an actual engagement of the clutch starts. This arrangement of the hydraulic clutch has an inherent problem of experiencing a delay prior to the actual engaging actuation. To solve this problem, it is important to determine the pressure that initiates the real engaging action of the friction clutch in engagement control or the pressure that completes the clearing of the ineffective part of the stroke of the clutch and sets the clutch into pre-engagement condition, and to utilize this determined engagement-control pressure for controlling the engagement actuation of the friction clutches.
Especially in a case where a friction clutch is used as a starting clutch in a vehicle, if the starting clutch, which has been relieved of the pressure used for an engagement actuation, is supplied again with oil to generate the pressure necessary for controlling the starting of the vehicle, there is a delay before the actual engaging action of the clutch occurs. When the pressure in the clutch increases, the part of the stroke of the piston which does not contribute to the real engagement of the clutch is cleared (hereinafter referred to as xe2x80x9cinvalid stroke clearingxe2x80x9d). After the completion of the invalid stroke clearing, when the starting clutch begins an actual engaging action, the pressure actuating the engaging action may become substantially large and make the clutch to engage abruptly, causing a problem of startup shock. If such an abrupt engagement occurs in the starting clutch, then the load on the engine will increase suddenly and may cause an engine stall.
Furthermore, for the purpose of improving fuel economy and reducing air pollution, many vehicles nowadays are equipped with an idling elimination control, in which the operation of the engine is stopped when the vehicle comes into a halt. In such a vehicle, when the vehicle starts, the engine must be started with the starting clutch being controlled to engage appropriately. Therefore, it is important to determine the pressure that sets the starting clutch into a pre-engagement condition, i.e., a condition where the starting clutch can start a real engaging action.
On this background, a control that learns and sets an optimal pressure for a frictionally engaging element such as a starting clutch has been developed and set in practice to achieve the above mentioned pre-engagement condition or an engagement-starting condition. For example, there is a method for learning the pressure at which the starting clutch begins the real engaging action by detecting a change in the load on the engine experienced when the transmission is shifted from a neutral position (N range) to a drive position (for example, D range) from a change in the negative pressure of the suction of the engine. Furthermore, in a vehicle whose fuel supply to the engine is controlled to stop while the vehicle is in deceleration, another method is applied for learning the pressure at which the starting clutch begins the real engaging action. This method is based on the fact that, in this vehicle, while the fuel supply is stopped during the deceleration, the slip factor of the clutch is controlled such that the torque-transmission capacity of the clutch calculated from the engagement-control pressure of the clutch equals the friction torque of the engine.
However, in a case where the pressure at which the starting clutch begins the real engaging action is determined based on the detection of a load change during a shift from the N range to the D range, there is a problem that if the rotational speed of the engine changes during the determination, then the determination cannot be performed accurately. This limitation, i.e., the determination must be carried out while the rotational speed of the engine is kept constant, makes the determination of the engagement-control pressure difficult to perform. While the fluctuation of the engine rotational speed is minimized, the engagement-control pressure of the clutch is changed slightly, and the transmission is switched between the drive ranges. By repeating the switching of the drive ranges, optimal pressure values are measured. However, the measurement performed in this way takes a relatively long period of time (for example, a few minutes). If the measurement takes a longer period of time, then it is more difficult to prevent a fluctuation in the rotational speed of the engine.
In a case where the pressure at which the starting clutch begins the real engaging action is measured on the basis of the engagement-control pressure of the clutch, whose slip factor is controlled while the vehicle is in deceleration with the termination of the fuel supply to the engine, it is necessary to decelerate the vehicle for the measurement to be performed. Therefore, the measurement in this case is a large scale operation and takes a long period of time.
As mentioned above, for a vehicle which is controlled to eliminate engine idling, it is important to determine the engagement-control pressure that sets the clutch into a real engaging action in the engagement control of the clutch at the starting of the vehicle. In this case, unless the vehicle is actually driven for the control system to learn the engagement-control pressure, the system sets the vehicle not to perform an idling elimination control. Therefore, before the vehicle is shipped out of a factory, the engagement-control pressure at which the clutch begins the real engaging action should be measured and determined by a test on a bench using the above mentioned method. However, this measurement operation takes a long period of time and is difficult to perform accurately as mentioned above. As a result, this operation increases the manufacturing cost of the vehicle. As there is a choice that such setting operation is not performed at the shipping of the vehicle, if it is not performed at the factory, then the idling elimination control of the vehicle is not performed until the engagement-control pressure is learned and set appropriately in real driving situations. This condition affects adversely the fuel economy of the vehicle and may cause the driver or owner to feel something wrong with the vehicle.
It is an object of the present invention to provide a method for measuring simply and quickly an engagement-control value when the frictionally engaging element (friction clutch) begins an engaging action or when it is set into a pre-engagement condition where it can start immediately an engaging action.
To achieve this objective, the present invention provides a method for controlling the engagement of a frictionally engaging element (for example, the starting clutch 5 described in the following embodiment) in a power transmission (for example, the continuously variable transmission CVT described in the following embodiment), through which engagement control, the rotational output of an engine is adjusted and transmitted to drive wheels. In this method, at least either the rotational speed of the engine or a parameter which corresponds to the rotational speed of the engine is measured while the frictionally engaging element is being actuated from a disengaged condition to an engaged condition, with the engine being operated under a constant operational condition. When there is a change in at least any of the rotational speed of the engine and the parameter being measured, an engagement-control value is calculated for the frictionally engaging element, and the engagement-control value calculated is stored as an initial control value used for starting the engagement of the frictionally engaging element, so that the initial control value is used to control the next engagement session of the frictionally engaging element.
By this method, while the operational condition of the engine is kept constant, only the engaging condition of the frictionally engaging element is changed to measure the initial control value at which the engaging action of the frictionally engaging element starts. This measurement can be performed simply and quickly (in about 10 seconds), so it can be performed simply, for example, at the end of a manufacturing line before the vehicle is shipped from a factory, without complicating a pre-shipment inspection. If the initial control value is set by this measurement in pre-shipment condition in this way, then the vehicle equipped with an idling elimination control can perform the idling elimination control without any problem immediately after the delivery of the vehicle. Therefore, the method according to the present invention can improve the product value of the vehicle.
The initial control value set in this way is used for the engagement control of the frictionally engaging element when the power transmission is operated for the first time. Thereafter, the engagement-control value at which the frictionally engaging element begins an engaging action is calculated from the engagement characteristic determined from the condition of the frictionally engaging element being controlled to engage in real driving situations. Preferably, the engagement-control value is calculated and used to renew the initial control value in memory, continually. In this way, the engagement control can be performed appropriately and accurately in correspondence to the real driving situation even if the frictionally engaging element undergoes deterioration with age.
In this method, the above mentioned parameter may be the suction negative pressure of the engine, and when the suction negative pressure changes to a higher load side and when the rotational speed of the engine decreases, the engagement-control value for the frictionally engaging element is stored as the initial control value.
On the other hand, although the suction negative pressure of the engine changes to a higher load side, if the rotational speed of the engine increases or does not change, then this condition is judged as a case of wrong learning, so the engagement-control value for the frictionally engaging element in this case is not stored as the initial control value.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

Method for controlling engagement of frictionally engaging element in power transmission


Disclosed herein is a clamping structure for mounting a reducer. The clamping structure include a clamp body 431 that is formed at opposite sides thereof with a door connecting portion 431a and a latch member connecting portion 431b to form a rectangular shape with one open side, and a clamp door 434 that can be rotated about a hinge pin 433 formed at the door connecting portion 431a, wherein the clamp door 431 is formed at one side thereof with a fastening portion, to which a latch portion of a latch member 450 is latched to allow a lever handle 446 of a lever member 440 to be pushed, and wherein the lever member 440 is coupled at one end thereof to the latch member connecting portion 450 of the clamp body 431 by a hinge 444 and is rotatably coupled at a middle thereof to the latch member 450 by a hinge 454 of the latch member 450.

1. Technical Field
The present invention relates to a clamping structure for mounting a reducer and, more particularly, to a clamping structure for mounting a reducer of fire sprinklers, in which a clamp door can be easily rotated about a rotation coupling point of a hinge pin to be tightly secured to an opposite side of the rotation coupling point.
2. Description of the Related Art
Generally, as buildings become taller and larger, various fire suppression apparatuses have been developed and used to achieve effective and efficient suppression of fire in the event of a fire in the buildings.
As fire suppression apparatuses are generally used, sprinklers capable of suppressing fire by spraying high-pressure water from the ceiling of each floor of buildings are essentially provided to the buildings.
In order to mount a sprinkler in a building, a main water supply pipe for supplying water through the ceiling is provided to the building, and the sprinkler is coupled to a connection pipe which connects a plurality of branch water supply pipes to the main water supply pipe, such that water is intensively supplied to a place, at which fire occurs, in order to suppress the fire.
In one example, referring to FIG. 1, Korean Utility Model Registration No. 20-0179175 assigned to the present inventor discloses a fire suppression apparatus including a sprinkler, which is connected to a lower side of a reducer 10 by a typical flexible joint and sprays water onto a predetermined place, wherein the reducer 10 is formed at four lateral sides thereof with contact surfaces 12 to be inserted into a square insertion hole 32, and a plurality of wing bolts 38 is secured to a predetermined number of screw holes 36 formed on a lateral side of a reducer securing bracket 30 having an opening 34, into which a square bar 20 is inserted, and applies pressure to the contact surfaces 12 of the reducer 10 by applying pressure to the square bar 20. The reducer securing bracket 30 is formed at upper and lower sides thereof with through-holes 35 and is secured to a screw support withdrawn from the ceiling by upper and lower nuts.
The contact surfaces 12 of the reducer 10 are formed by cutting a round outer surface of the reducer 10, and the reducer 10 is formed at the lower side thereof with a sprinkler mounting portion 26 to which a sprinkler head is secured.
In another example, referring to FIG. 2, a clamp 300 disclosed in Korean Patent No. 10-1014385 based on the technique of FIG. 1 can be moved to a desired place, with a support frame (square bar) 100 inserted into one side of a clamp body 131, and a nut 138c serving to open or close a clamp door 134 is loosened, such that the clamp door 134 can be rotated about a hinge pin 133 to be opened. The clamp body 131 and the clamp door 134 are formed with a clamp groove 132 and a coupling groove 135, respectively, to define a space capable of receiving a body 222 of a sprinkler 200 when the body 222 is inserted into the clamp 300. Thus, in order to provide a clamping state between the clamp 300 and the sprinkler 200, the body 222 of the sprinkler 200 is inserted into the clamp door 134 in an opening/closing direction of the clamp door 134 without separating a spray nozzle 224 from the body 222, and, with the clamp door 134 closed, a bolt coupling rod 137c coupled to the clamp body 131 is inserted into a securing groove 136 of the clamp door 134, and then, a nut 138c is fitted to the bolt coupling rod 137c.
However, as shown in FIG. 1, in the above example, since the square insertion hole 32 is formed in the reducer securing bracket 30 and the reducer 10 is inserted and secured thereto, the reducer 10 provides good tightness, but has a problem in that separation or disassembly is inconvenient.
Moreover, as shown in FIG. 2, in the other example, since the clamp 300 has the structure wherein the clamp door 134 is rotated about the rotation coupling point of the hinge pin 133 to allow the securing groove 136 of the clamp door 134 to be open at one side thereof such that the nut 138c is fitted to the bolt coupling rod 137c inserted into the securing groove 136, there are problems in that coupling is difficult and disassembly operation is inconvenient due to the need to rotate the nut 138c during disassembly. In addition, since the securing groove 136 of the clamp door 134 has the one side-open structure, when a strong torque of 900 Kg/m2 or more is applied to the clamp 300, the clamp body 131 and the clamp door 134 come apart or are distorted, thereby making it difficult to use the clamp 300.


A process for the elimination of mercury from an overall steam cracking installation, characterized in that regeneration is terminated by the injection of regeneration gas onto an active demercurizing mass, such that there is substantially no trace of mercury in the air or liquids leaving the installation. The process involves the use of three demercurizing masses, namely two upstream of the installation which are in series and one downstream, which latter is demercurized by at least one of the upstream masses. The use more particularly applies to the depollution of steam cracking installations which are already polluted by mercury.

It is known that liquid condensates constituting the byproducts of gas production (natural gas, associated gas) and crude oil can contain numerous metallic compounds in the trace state and in particular mercury.
These charges are increasingly steam cracked and the consequence of this is to produce effluents polluted by mercury. The catalysts of the transformation processes located downstream of the steam cracking process are consequently severely poisoned, which in certain cases makes the gas condensates economically less attractive. In addition, mercury may also cause corrosion through the formation of amalgams with aluminium-based alloys, particularly in sections of the plant operating at a sufficiently low temperature to cause the condensation of liquid mercury (cryogenic fractionation, exchangers).
The prior art discloses numerous products having an interesting demercurizing activity. Thus, there are masses constituted by active carbon impregnated with sulphur or iodine in U.S. Pat. No. 3,194,629 and copper oxide in U.S. Pat. No. 4,877,920. U.S. Pat. No. 4,843,102 claims the use of a polysulphide-impregnated resin, as does U.S. Pat. No. 4,877,515, which deposits these polysulphides on a molecular sieve. According to U.S. Pat. Nos. 4,892,567 and 4,874,525 sometimes the molecular sieve is impregnated by a metal known to form amalgams such as gold or silver. U.S. Pat. No. 3,194,629, assigned to Institut Francais du Petrole (IFP) describes other masses incorporating copper at least partly in the sulphide form and a mineral support.
These different masses are very effective for trapping the metallic mercury, but relatively ineffective when the metal is combined in the form of dimethyl mercury or mercury compounds having hydrocarbon chains containing two or more carbon atoms and optionally other non-metallic elements (sulphur, nitrogen, etc.). In order to ensure a complete elimination of the mercury in all cases, IFP has described two processes constituted by two reaction zones in series containing two masses preferably used in series, the first carrying out the hydrogenolysis of the organometallic compounds in the presence of hydrogen and the second trapping most of the mercury contained.
Thus, French patent application FR-A-89/03581 describes the first catalyst as containing at least one metal M from the group constituted by nickel, cobalt, iron and palladium and followed by or mixed with a trapping mass containing sulphur or a metal sulphide.
French patent application FR-A 89/03500 describes the first catalyst as containing at least one metal M chosen from the group formed by nickel, cobalt, iron, palladium and platinum, at least one metal N chosen from the group formed by chromium, molybdenum, tungsten and uranium followed by or mixed with a mercury trapping mass containing a sulphide of at least one metal P chosen from the group formed by copper, iron and silver, or sulphur.
As these two processes operate in the presence of hydrogen, they cannot be used on cracked gases, which contain significant quantities of unsaturated compounds. It is therefore necessary to use them upstream of the steam cracker, while pretreating the charge. Such a situation is very interesting, because it makes it possible to ensure the elimination of the mercury from the entire installation on all the unsaturated fractions produced. It also prevents mercury pollution of installations in contact with the cracked gases prior to their separation into different fractions.
Nevertheless many steam cracking installations (zones) have operated with mercury-polluted charges without using any mercury elimination technology at all. In this case the complete installation is polluted by mercury and the limited, but not negligible, steam affinity for of this metal means that even the mercury-free effluents, because the steam cracker charge has been treated, could again become charged with mercury.
It is also standard practice to "import" unsaturated fractions in addition to those produced in situ in order to increase the flexibility of the installation. In this case it is not sufficient to eliminate the mercury from the steam cracker charge and it is also necessary to install trapping masses on the cracked products. In this case it is possible to use the various products referred to hereinbefore, but they all suffer from the disadvantage of a polluting reprocessing.
Thus, resins must be treated with solutions which entrain the trapped mercury, which imposes expensive downstream treatments. Carbons must be burned in order that it is possible to recover the active phase deposited on their surface, which causes a problem of serious pollution of the combustion fumes, which are seriously polluted by the volatile mercury. Molecular sieves are usually regeneratable, but here again it is necessary to have an installation making it possible to eliminate the mercury from the regeneration effluents.
However, the mercury trapping masses used upstream, like those described in French Application FR-A-89/03581 and 89/03500 are mineral products which have a composition similar to the ores containing the mercury. It is therefore standard practice to treat such solids in order to extract therefrom the metallic components and also the mercury contained.

Process for eliminating mercury from steam cracking installations


A semiconductor device includes a P-type semiconductor substrate, an N-type well region formed on the surface of the substrate, a P-type well region formed in the N-type well region and a MOSFET as a flash memory element formed in the P-type well region. Upon erasure of the information in the flash memory, a high voltage is temporarily charged to the P-type and N-type well regions, in such a manner that a first high voltage pulse of a predetermined width is charged to the N-type well region, a second high voltage pulse having a pulse width narrower than the pulse width of the first pulse is charged to the P-type well region in a period between the initiation end and the termination end of the first pulse.

The present invention relates generally to a semiconductor device. More specifically, the invention relates to an improvement for a voltage control circuit device for a well region on a semiconductor substrate during erasure of information in a flash memory capable of electrically writing and erasing information.
An electrically writable and erasable flash memory has been disclosed in "An 80-ns 1-Mb Flash Memory With One-Chip Erase/Erase-Verify Controller", IEEE JOURNAL OF SOLID-STATE CIRCUITS, Vol. 25, No. 5, October, 1990, pp 1147.about.1151, for example. When the flash memory is fabricated into an integrated circuit together with peripheral circuits, it is typically formed into the following construction.
An N-type well region is formed on the surface of a P-type silicon substrate. A P-type well region is formed within the N-type well region. N-type doped regions serving as a drain and a source of a memory element is formed within the P-type well region. On the P-type well region between the drain and source, a floating gate and a control gate are formed.
When the information in the memory element is to be erased, a high voltage is charged to the N-type well region and the P-type well region. At this time, if there is a difference in resistivities, junction capacitances or so forth between the N-type well region and the P-type well region, it is possible to establish a forward bias at PN junction between the well regions, in the transition of the voltage variation from the grounding voltage to the high voltage of the P-type and N-type well regions. Then, holes are injected from the P-type well region to the P-type silicon substrate via the N-type well region. This is a defect because it leads to an unnecessary increase in power consumption. Also, it is possible to cause latching up of a circuit formed by other complementary type MOS transistor by the hole.
Therefore, it is an object of the present invention to provide a semiconductor device which can prevent a temporary forward bias from occurring between the well regions, upon charging a high voltage to the P-type well region and the N-type well region.
Another object of the present invention is to provide a semiconductor device which can certainly maintain a reverse bias between the well regions upon erasure of information in the flash memory and thus will never affect, such as latching up or so forth, for other circuit.


A spotlight has an adjustable angle of radiation with modification of the angle of radiation being achieved in a manner other than by shading a beam path with a screen or mask. The spotlight has an interior light source (4) and a first lens (2) that is structured as a front lens. The first lens (2) is an aspherical lens.

This application claims a priority based on German Patent Application DE 199 01 391.8, filed Jan. 15, 1999, and the disclosure of that application is incorporated herein by reference.
The invention relates to a spotlight with an adjustable angle of radiation, wherein modification of the angle of radiation is achieved in a manner other than by shading a beam path with a screen or mask, having a light source arranged within the spotlight and a first lens that is a front lens of the spotlight. Profile projectors, in which small modifications of angles of radiation occur as a side effect during image focusing, do not belong to this class of spotlights.
Spotlights with adjustable angles of radiation as known in the prior art can be divided into three classes, namely stepped lens spotlights, spotlights with very deep reflectors, and spotlights with an optical unit, including a second lens, a light source, and a reflector, that is moveable relative to a front lens.
Conventional stepped lens spotlights have a single stepped lens (Fresnel lens). Incandescent bulbs, halogen bulbs, or discharge lamps are used as light sources in these stepped-lens spotlights. The light source and a reflector are mounted on a slide at a fixed distance from each other. The slide is movable relative to the Fresnel lens. Focusing is achieved by moving the slide. However, in stepped lens spotlights of this type, a significant effective loss of light occurs at focus settings with small angles of radiation. Since there is no second lens to concentrate the light toward the Fresnel lens, a large portion of the light emitted by the light source is simply absorbed by an inner wall of a housing at such focus settings, which results in loss of light and unneeded heating of the housing.
In general, a spotlight with a very deep reflector is constructed so that the lamp and reflector can be displaced relative to each other, but in these spotlights the lamp remains inside the reflector, along its optical axis, at all times. The angle of radiation of these spotlights is modified by changing the position of the lamp within the reflector. However, a focusing path that can be achieved in this way is minimal, so that an angle of radiation can be varied only within relatively narrow limits. Spotlights of this type do provide a high degree of light efficiency, but they exhibit unfavorable light distribution in nearly all lamp positions. A reason for this generally poor light distribution is that a particular fixed reflector shape provided respectively for each one of these spotlights, relative to a resulting light distribution, can be optimally designed for only a single lamp position. Uneven light distribution occurs when the lamp or the reflector are moved for focusing purposes, for example. Therefore, to improve light distribution, replaceable front lenses are often used in spotlights of this type. These lenses may have frosted properties, a honeycomb structure, or other specially formed features that serve to provide additional focusing or light dispersion, in which, however, aspherical front lenses have never before been used in spotlights with adjustable angles of radiation. With these spotlights, therefore, variously modified front lenses must be used for various angles of radiation. For many such spotlights with very deep reflectors, both the lamps and the reflectors are mounted in fixed positions in the housings, i.e. the angles of radiation are modified in such cases exclusively by replacing variously-shaped front lenses. This entails a relatively significant amounts of labor and time spent changing front lenses if such a spotlight is-used in a situation in which the angle of radiation must be often changed.
Spotlights with adjustable angles of radiation of the third group, in accordance with the above classification, are a significant improvement over the spotlights described above. Such a spotlight is disclosed by U.S. Pat. No. 4,823,243 and European Patent 0 846 913. This spotlight has a light source, a reflector associated with the light source, a first collector lens (front lens) placed in a beam path in a direction of a beam of the light source-reflector combination, and a second collector lens located between the light source and the first collector lens. The reflector, the light source, and the second collector lens are mounted as an optical unit that is movable relative to the first collector lens along an optical axis of the spotlight. Inside the optical unit disclosed in U.S. Pat. No. 4,823,243 a spacing between the light source and the second collector lens is adjustable. Very similar spotlights are also commercially available in which, however, mutual spacings between a reflector, a light source, and a second collector lens cannot be modified. In the latter spotlights, optical units can be moved only as fixed wholes. By contrast, in the spotlight disclosed in European Patent 0 846 913, within the optical unit that can be moved relative to the first collector lens, both the spacing between the light source and the second collector lens and the spacing between the light source and the reflector can be modified. Common to all the spotlights described in this paragraph, however, is that the front lens is a spherical lens.
The spotlights with adjustable angles of radiation specified in the previous paragraph, one of which is shown in a schematic view in FIG. 5, provide a large modification range of angles of radiation (see FIGS. 6a, 6b herein), and achieve a high degree of light efficiency in terms of energy required to operate spotlights. In addition, they provide exceptionally even light distribution. Moreover, such a spotlight no longer produces scattered light (light intensityxe2x89xa650% of maximum light intensity), as defined according to a conventional concept, owing to a sharp slope of the light intensity at the edge of the lighted area. As shown in FIGS. 6a, 6b, a characteristic illuminance curve of a lighted field does exhibit small increases in intensity at the edge, the size of which depends on the setting of the optical unit, but the light intensity across the entire lighted area is largely constant. Increases in intensity at the edge do not occur in the spot setting. They appear only upon movement of the spotlight out of the spot setting and then increase continuously in size until a critical setting in the angle of radiation between the spot setting and the flood setting is achieved, in which the size of the intensity increase at the edge reaches a maximum. Upon further movement of the spotlight in a direction toward the flood setting, the size of the intensity increase at the edge once again decreases continuously.
If graining, or pocking, is provided on a surface of the second lens so that a micro-lens structure arises on the grained surface, the intensity increase that occurs at the edge in the characteristic illuminance curve is dampened, but not entirely eliminated. Moreover, this reduction in intensity increase at the edge is achieved at a cost of increased scattering and loss of light.
It is an object of this invention to provide a spotlight of the type mentioned in the opening paragraph above that provides a more even light distribution, particularly in angle of radiation settings outside the spot setting, than do such spotlights known in the prior art.
According to principles of this invention, a spotlight, whose angle of radiation is modified in a manner other than by shading a beam path with a screen or mask, includes an interior light source and a first lens that is a front lens of the spotlight, with the first lens being an aspherical lens.
Use of an aspherical lens as a first lens, i.e. as a front lens of such a spotlight, ensures a more even light distribution outside of the spot setting in comparison to such spotlights known in the prior art.
The term xe2x80x9caspherical lensesxe2x80x9d means lenses in which at least one partial surface is not spherical in structure, with plane faces being always counted as spherical surfaces. Examples of aspherical lenses are lenses having one ellipsoid and one spherical surface, and lenses having one spherical surface and one hyperbolic surface. Fresnel lenses having aspherically structured partial surfaces are also aspherical lenses according to the above definition.
Advantageous and preferred embodiments of spotlights having enhanced features of this invention are described herein.
In one embodiment of a spotlight of this inventionxe2x80x94in which a second lens is placed in a light-beam path between the light source and the first lens, with a reflector, the light source, and the second lens being mounted as an optical unit that is movable along an optical axis of the spotlight relative to the first lensxe2x80x94prior-art edge-intensity increases in light distributions are entirely smoothed out, and particularly uniform lighting of the lighted area is achieved, with a high degree of variability of the angle of radiation, independently of selected settings of the angle of radiation.
In a spotlight according to the invention in which the second lens is grained on at least one surface, the graining does not need to be made as deep as graining of a second lens commonly known in the prior art. In this way, loss of light is reduced and, as is particularly important in the spot setting, greater light intensity is achieved with the same input power.
In a particularly preferred embodiment in which the second lens is an aspherical lens, light efficiency in the spot setting is increased in comparison with a second lens structured as a spherical lens, with the same input power.
Particularly uniform light distribution is achieved with embodiments of the spotlight wherein the lenses have surfaces formed in accordance with the equations disclosed and claimed herein.
In an embodiment of the spotlight according to the invention in which a spacing between the light source and the second lens is adjustable within an optical unit, it is ensured that the spotlight also has all the advantages of the spotlight disclosed in U.S. Pat. No. 4,823,243.
In an embodiment of the spotlight of the invention in which a spacing between the light source and the reflector is adjustable within the optical unit, it is ensured that the spotlight also has all the advantages of the spotlight disclosed in European Patent 0 846 913, specifically the very great variability of the angle of radiation and of the light intensity.

Spotlight with an adjustable angle of radiation and with an aspherical front lens