A frequency domain electromagnetic geophysical mapping instrument has a transmitter, a transmitter coil connected to the transmitter, the transmitter generating current pulse waveforms formed by half-sinusoidal output waveform segments of a waveform having a frequency equal to a resonant frequency of the transmitter coil, and a receiver, in which the transmitter generates current pulses including pulses comprising a plurality of immediately successive half-sinusoidal waveform segments of common polarity. The pulses immediately succeed each other and are of alternating polarity. The pulse lengths may in this case be equal, or vary in a manner providing a desired output spectrum, for example according to a pseudo-random sequence.

1. Field of the Invention
This invention relates to electromagnetic geophysical mapping instruments.
2. Review of the Art
In my co-pending patent application Ser. No. 08/657,454 now U.S. Pat. No. 5,796,253 the disclosure and drawings of which are incorporated herewith by reference, there is disclosed a time domain electromagnetic geophysical mapping instrument having a transmitter, the transmitter having a transmitter including a transmitter coil, the transmitter generating intermittent current pulse waveforms, formed by half-sinusoidal output wave form segments of a waveform having a frequency equal to a resonant frequency of the transmitter coil, and a receiver including a receiver coil, in which the transmitter generates current pulses which typically comprise a plurality of immediately successive half-sinusoidal waveforms of common polarity.
Techniques for the application of frequency-domain electromagnetic (FDEM) instruments for general geological mapping and the direct detection of sub-surface metallic mineral deposits have been well documented over the years. FIGS. 1A and 1B depict typical FDEM system configuration for airborne and ground based systems respectively.
The technique is based on the measurement of the secondary magnetic field from subsurface targets, as a result of the primary alternating magnetic field established by the system transmitter.
In its simplest form, the typical system will operate at a single frequency with a single receiver transmitter coil pair. To obtain as much information as possible about the subsurface target a range of single frequencies is transmitted and the responses measured one at a time in sequence. To cover the necessary range of frequencies, a long measuring time is required. This makes system operation inefficient and time consuming.
Sometimes, especially in airborne systems, multiple transmitter and receiver sets are employed, operating at different frequencies, so that information at multiple frequencies is obtained simultaneously. The multi-coil system is very often complex, heavy and expensive to build and maintain.
A wideband current waveform can be generated to allow fast multi-frequency electromagnetic field measurement by employing pulse modulation techniques. The conventional pulse modulation technique utilizes a pseudo-random binary sequence, where the multi-frequency signal is generated in a simple, straight forward and controlled manner. The pseudo-random binary signal has well defined frequency spectrum and it is simple to build and implement.
FIG. 2A shows an example of a pseudo-random signal waveform a and FIG. 2B shows its power spectrum.
Other waveforms, for example a square waveform, can also be used to generate a spectrum of frequencies.
In order to achieve the maximum depth of exploration, having regard to external and internal system noise, it is necessary to maximize the transmitter dipole moment (product of transmitter coil area, number of turns and output current).
There is always constraint on transmitter coil area (size) and available power, so that a practical way to increase dipole moment is to increase the number of turns of the transmitter loop.
Since the inductance of a multi-turn loop is proportional to square of the number of turns according to the relationship L=KN2(a+b) where: L is inductance of the loop, N is number of turns, a and b are loop dimensions and K is a constant, multi-turns loop in general have large inductance and therefore high impedance that prevents the use of large currents. In order to overcome the high impedance of the transmitter loop, the output coil is often resonated with a capacitor to a particular frequency, a technique well known to the radio-engineering community.
If at a particular frequency, a capacitor in series with transmitter loop is selected so to have the same absolute impedance as the coil inductance, the maximum current will be supplied to the output coil. This is illustrated by FIG. 3, in which the circuit values shown are related as follows;             i                    (        t        )              =                  e                          (          t          )                            r        +                  (                      ϖL            -                          j                                            1                ϖC                                              )                                        if              ❘              ϖL        ❘              =          xe2x80x83                          ❘                              1            ϖC                    ❘
                                                        Then                                                  xe2x80x83                                                  i                                            (                t                )                                                                      xe2x80x83            =              xe2x80x83                                    e                                (            t            )                          R
It is an object of the present invention to combine the efficiency of a tuned transmitter coil with a wide band output, using a transmitter arrangement of the kind described in the parent application; the invention employs such a transmitter in a frequency domain electromagnetic mapping instrument, utilizing for example a pseudo-random input signal waveform to the transmitter.
The invention thus provides a frequency domain electromagnetic geophysical mapping instrument comprising a transmitter and a transmitter coil connected to the transmitter, the transmitter generating current pulse waveforms, formed by half-sinusoidal output waveform segments of a waveform having a frequency equal to a resonant frequency of the transmitter coil, and a receiver, in which the transmitter generates current pulses comprising a plurality of immediately successive half-sinusoidal waveforms of common polarity, the pulses immediately succeeding each other being of alternating polarity. The pulse lengths may be equal, or vary in a manner providing a desired output spectrum, for example according to a pseudo-random sequence.

Frequency domain electromagnetic geophysical mapping instruments


Changes occurring downhole during a fracturing process can create or reflect pressure signals. Capturing and evaluating such pressure waves during fracturing enables personnel to monitor, in real time or later, what happens downhole. When a fracture extends, a burst of acoustic noise is embodied in a pressure wave or signal, as is noise coming from other sources. By transforming time-based pressure signals to a frequency base, one can monitor this acoustic noise. In a particular implementation, a waterfall plot of frequency spectra at successive time slices of the original signal is used to determine frequency ridges, such as a ridge of decreasing frequencies indicates fracture extension and a ridge of increasing frequencies indicates either closure or proppant backing up in the fracture. Filtering, such as wavelet filtering, can be used. A fracturing process can be controlled in response to determining whether the fracture is extending.

This invention relates generally to fracturing subterranean formations and to fracture monitoring methods.
There are various uses for fractures created in subterranean formations. In the oil and gas industry, for example, fractures may be formed in a hydrocarbon-bearing formation to facilitate recovery of oil or gas through a well communicating with the formation.
Fractures can be formed by pumping a fracturing fluid into a well and against a selected surface of a formation intersected by the well. Pumping occurs such that a sufficient hydraulic pressure is applied against the formation to break or separate the earthen material to initiate a fracture in the formation.
A fracture typically has a narrow opening that extends laterally from the well. To prevent such opening from closing too much when the fracturing fluid pressure is relieved, the fracturing fluid typically carries a granular or particulate material, referred to as "sand" or "proppant," into the opening of the fracture. This material remains in the fracture after the fracturing process is finished. Ideally, the proppant in the fracture holds the separated earthen walls of the formation apart to keep the fracture open and provides flow paths through which hydrocarbons from the formation can flow at increased rates relative to flow rates through the unfractured formation. In another application, acids are used to create uneven surfaces so that the fracture does not completely close, thus still providing effective flow channels through the fracture.
Such a fracturing process is intended to stimulate (that is, enhance) hydrocarbon production from the fractured formation. Unfortunately, this does not always happen because the fracturing process can damage rather than help the formation (for example, proppant can clog the fracture tip to produce a "screenout" condition).
Stimulating wells that behave nicely (for example, wells that are easily stimulated) allows service companies and operators to follow standard procedures commonly performed on such wells. No special attention needs to be placed upon specifics, such as how the fracture behaves; decisions and actions are based upon the experience the industry has acquired over many years.
However, as the hydrocarbon supply decreases and demand for it increases, the hunt for hydrocarbons becomes more challenging. New technologies, such as fluid chemistry and rheology, or even new stimulation techniques enter the marketplace. These techniques claim to provide better fracture creation, better conductivities, permeability modifications, and more. As these technologies are used, new methods for evaluating the effectiveness of the treatments are needed.
In at least these more challenging situations, fracture behavior is an important aspect in fracturing technology. Many techniques are available for pre-stimulation simulations and post-stimulation analyses of fracture behavior; however, few techniques address fracture behavior during the stimulation process itself. Various fracture behaviors, such as fracture extension, ballooning, and tip screenout are often not known to the operator until after it is too late or even after the job is completed. Therefore, there is a need for real-time analysis or monitoring of fractures.

Fracture monitoring using pressure-frequency analysis


Disclosed are new coatings compositions based on an HDI isocyanurate or biuret polyisocyanate and a bis(imine) reaction product of a diaminoalkane containing between two and five carbon atoms with an alkyl aldehyde containing between four and seven carbon atoms (advantageously a bis(imine) product of the reaction of 1,4-diaminobutane and isobutyraldehyde). The latter bis(imine) is completely miscible in HDI isocyanurate and biuret polyisocyanates, and, as a reactive diluent, allows the preparation of high performance coatings formulations that require only small amounts of solvents to achieve a conveniently sprayable viscosity.

Difunctional aldimines and ketimines, that is condensates of diamines with aldehydes or ketones, or, the condensates of dialdehydes or diketones with primary amines, are known in the prior art. The use of aldimines and ketimines in urethane coatings and sealant compositions is also known. For example, their use as-catalysts for urethane coatings and sealant systems are described in U.S. Pat. Nos. 3,553,118 and 3,637,903. Other disclosures of aldimines and ketimines in the prior art are largely directed at their use in moisture cure systems: for example, together with blocked isocyanate terminated. prepolymers (see U.S. Pat. Nos. 3,267,078; 4,507,443; and 4,847,319); and, with free isocyanate curatives (see U.S. Pat. Nos. 3,420,800; 3,440,087; 3,567,692; 3,589,932; 3,629,013; and 3,793,417). This last patent, U.S. Pat. No. 3,793,417, shows the use of systems based on aldimines, isocyanates and polyols in moisture and in heat cured coatings.
The bis(imine) reaction product of 1,4-diaminobutane with isobutyraldehyde is known and disclosed, for example, in U.S. Pat. No. 2,416,042. Additional information relating to the production and photochemistry of these compounds is disclosed in a 1985 technical journal article (J. Inst. Org. Khim., Moscow, USSR, 1985, 7, 1612-15) and in a 1991 technical journal article (Bittner and Rademacher, J. Chem. Research (S), 1991, 60-61), respectively.
Japanese Kokai JP 07 18,051, published on Jan. 20, 1995, discloses a polyurethane elastomer-forming composition containing, inter alia, a urethane prepolymer of 2,4-TDI, polyoxypropylene glycol, polyoxypropylene triol and a dialdimine obtained by reacting 1,4-diaminobutane and p-tolualdehyde. This elastomer-forming composition is said to exhibit good storage stability.
U.S. Pat. No. 5,214,086 discloses a plethora of aldimine and ketimine compounds within an empirical structural formula shown for such compounds. The compounds of the '086 patent are disclosed therein as reactive diluents for reducing the volatile organic content ("VOC") of a paint composition by increasing the solids content of the paint without adversely affecting the paint's performance.
Reactive diluents, such as the above-discussed difunctional aldimines are referred to as diluents since they have low viscosities, and are reactive, inasmuch as they participate in the film forming reaction during the formation of a coating. In view of these characteristics of reactive diluents, they are suitably employed to replace some or most of the solvent that is otherwise needed to reduce the viscosity of a coating formulation to a desired low viscosity, thereby reducing the quantity of VOCs emitted by the system, an advantage from an environmental and toxicology standpoint.
It has now been found by the present inventors that previously known aldimine and ketimine reactive diluents, such as those specifically described, for example, in the above-discussed '086 patent, suffer from a key deficiency. More specifically, these reactive diluents have relatively low solubility in polyisocyanates that comprise HDI isocyanurates ("trimer") and/or HDI biurets. Since a completely miscible system is a prerequisite for insuring a homogeneous film to provide good physical properties in the resulting coating, such low solubility reactive diluents require the use of additional formulation steps and/or solubilizing additives to permit the use of these reactive diluents in coating compositions to provide high performance coatings having good physical properties. Illustrative steps and solubilizing additives needed when using these prior art reactive diluents include, for example, the following: (a) using higher levels of solvents, which undesirably increases the formulation's VOC content; (b) replacing some or most of the isocyanurate or biuret polyisocyanate with an HDI uretidione based polyisocyanate, which reduces the average isocyanate functionality of the system and thereby reduces the crosslink density and the corresponding physical properties of the resulting film; and/or, (c) using lower molecular weight, lower functionality isocyanate reactive resins, which, likewise, reduces the crosslink density and performance characteristics of the resulting film. The second (b) and third option (c) also restrict the number of suitable isocyanate curatives and isocyanate reactive resins available to the coatings formulator, thus rendering the development of such systems more inflexible than otherwise might be desired.
Thus, there is a heretofore unsatisfied need in the marketplace for an imine-type reactive diluent that is completely soluble in HDI isocyanurate and biuret based polyisocyanates. Several such highly desirable reactive diluents are provided by virtue of the present invention.

Bis(isobutyraldimine) of 1,4-diaminobutane in HDI trimer and biuret-based coatings


A radiation shielding integrated circuit device comprising a x-ray shielding layer for shielding an electronic circuit device from receiving an amount of x-rays greater than the total dose tolerance of the electronic circuit device; a base coupled to the x-ray shielding layer; a radiation shielding top coupled to the base; a radiation shielding bottom coupled to the base; and the electronic circuit device coupled to the x-ray shielding layer; wherein the electronic circuit device is shielded from receiving an amount of radiation greater than a total dose tolerance of the electronic circuit device.

1. Field of the Invention
The present invention relates generally to integrated circuits. More specifically, but without limitation thereto, the present invention relates shielding integrated circuits from ionizing radiation and x-rays.
2. Discussion of the Background Art
In many radiation environments electronic circuits must be shielded from ionizing radiation and x-rays in order to function properly. For example, in a space environment, circuit die must be shielded from ionizing radiation or the circuit may fail to function properly. In other environments, e.g., where the risk of exposure to artificial nuclear radiation is high, the circuit must be shielded from x-rays.
Previous practices use an ionizing radiation shield to shield from ionizing radiation found in the natural space environment. Ionizing radiation found in the natural space environment is comprised primarily of electrons and protons with a small number of ionized highly energetic heavy ions. The electrons and protons contribute to the integrated radiation damage of a semiconductor device and is frequently called ionizing radiation. Ionizing radiation creates total dose damage in electronic circuits. The damage is frequently cumulative over the entire time the device is in space or in the ionizing radiation environment. Since, for the most part, the ionizing radiation found in space is isotropic, incomplete coverage of package shielding allows for only a percentage of radiation to leak through, which percentage can be predetermined. As shown in FIG. 1, by way of example, this radiation leakage occurs through the sides of the packaging where there is no radiation shielding material. Ionizing radiation comes from every direction, therefore allowing a certain amount of side radiation leakage is acceptable as long as it does not exceed the total dose tolerance of the circuit die.
In contrast, x-ray radiation resulting from, e.g., artificial nuclear detonations comes from substantially a single direction, which in many instances can not be predetermined. This type of x-ray radiation, or burst radiation, usually comes from a man-made event such as a nuclear detonation. X-ray radiation usually generates dose rate damage in electronic devices, because of the extremely short time frame that the burst exist. This type of damage is different from the slower total dose damage that occurs for the natural space radiation environment. X-ray radiation is electromagnetic and therefore the shielding effectiveness of materials is different from that of ionizing radiation. Additionally, since the direction from which x-ray radiation, such as burst radiation, will come can't be predetermined and because substantially all of such radiation comes from substantially a single direction, the shielding shown in FIG. 1 is insufficient as a very large dose of x-ray radiation could come from an angle which is not protected.
FIG. 1 illustrates a shielding package designed to shield from ionizing radiation, such as found in a natural space environment.
FIG. 1 shows a radiation shielding top 102, a radiation shielding bottom 104, a plurality of circuit die 106, a plurality of conductors 108, a base 110, and a line of sight angle 112.
As shown in FIG. 1, the plurality of circuit die 106 are shielded by the radiation shielding top 102 and the radiation shielding bottom 104. This shielding is sufficient to shield the plurality of circuit die 106 from an amount of radiation greater than the total dose tolerance of the plurality of circuit die 106. However, the line of sight angle 112 represents an exposed line of sight not protected by shielding material. Therefore, burst radiation coming from within the line of sight angle 112 may directly impact with the plurality of circuit die 106 and cause severe damage or destroy the operation of the plurality of circuit die 106.
Thus there is a need for package design to eliminate the problems discussed above.

Method and apparatus for shielding an integrated circuit from radiation


Interferometric scanning method(s) and apparatus for measuring optics either having aspherical surfaces or that produce aspherical wavefronts. A test optic is aligned and moved with respect to a scanning axis relative to the origin of a known spherical wavefront that is generated with a reference surface to intersect the test optic at the apex of the aspherical surface and at radial zones where the spherical wavefront and the aspheric surface possess common tangents. The test surface is imaged onto a space resolving detector to form interferograms containing phase information about the differences in optical path length between the reference surface and the test surface while the axial distance which the test optic moves relative to the spherical reference surface is interferometrically measured. The deviation in the shape of the aspheric surface from its design in a direction normal to the aspheric surface is determined and reported.

Aspherical surfaces have become more and more important in modern optical systems because they offer a higher number of parameters for simplifying systems while optimizing their performance. This can lead to systems with less surfaces, less weight, smaller dimensions and higher states of correction, to mention only a view advantages. This is especially true in fields where a high number of optical surfaces are not practical, like in astronomical telescopes or normal incidence reflecting surfaces for the EUV wavelength of 13.6 nm used for lithography tools where it is mandatory to keep the number of surfaces as low as possible. In such cases, there is no choice but to use aspherical surfaces. With demands for high quality performance for complete systems operating in the EUV-regime; the surface errors of reflecting surfaces within such a system must be kept below 0.1 nm, and the measuring accuracy and precision for such errors must be even higher to be able to produce the surfaces in a deterministic manner. In addition, lens surfaces in multi-element lithography lenses operating at wavelengths of 193 nm and 157 nm are made aspherical to lower the number of elements made, which are of rare and expensive materials. In these cases, the departures from a best fitting sphere can be as large as 1000 μm, and the dimensions of such lens surfaces have increased to nearly 500 mm.
In an optical system, the function of any of its lens elements is to modify the wavefront transmitted by the individual lens elements according to the optical design of the whole system. If a spherical wave or a plane wave enter such a lens, an aspherical wavefront with a very high departure from the best fitting sphere is produced, depending on the conjugates used in the particular test-configuration. So even the fundamental single lens element with either spherical or aspherical surfaces can only be tested properly if one is able to deal with aspherical wavefronts in a test set-up. Moreover, this ability is very important to testing wavefronts transmitted through lens elements because inhomogeneity of the lens material itself can deteriorate the wavefront even when the surfaces are otherwise free of error.
The measurement of aspherical surfaces and wavefronts has been very difficult because of the large departure from the best fitting sphere. With interferometric measurements, high precision is by making the dynamic range of the measurement very small, and for this purpose, the wavefront of the reference wavefront, against which the aspherical wavefront is compared, has to be made aspherically as well to ideally fit the wavefront to be measured completely. In prior art, this has been done either by refractive systems, so called "null-lenses", or with diffractive elements, so called "computer generated holograms", which alter a wave of known and measurable shape (spherical or preferably plane wave) as it transits the compensation element to fit the design aspherical surface at the location where it is placed in the test-set up by design.
In all these cases, the compensation element must be tested to be sure that the correct wavefront is delivered for comparison. But, it is obvious that the same difficulties exist for this type of testing because, again, an aspherical wavefront is produced. Therefore, only indirect test methods are, applied by, for, instance, measuring the surface of each lens element used in a null system, which is exclusively built with the help of spherical surfaces. Also, the refractive index of the lens material, the lens thickness and the air-spacing of the lenses are measured carefully. Nevertheless, the final accuracy is questionable because of accumulation of measurement errors and the uncertainty of the homogeneity within the lens, material.
There are many methods and apparatus in the prior art for measuring aspherical optical surfaces, for example: 1. Contacting and non-contacting stylus based profilers; 2. Contacting and non-contacting stylus based coordinate measuring machines; 3. Spherical wavefront interferometers; 4. Lateral and radial shearing interferometers; 5. Interferometers with null lenses in the measurement path; 6. Scanning spherical wave interferometers; 7. Scanning white light interferometers; 8. Sub-aperture stitching interferometers; 9. Interferometers using computer generated holograms-CGHs; 10. Point diffraction interferometers-PDis; 11. Longer wavelength interferometry; and 12. Two wavelength interferometry. While these techniques have utility for many applications, they are limited in their operational capabilities or precision compared with those needed for today's evolving lithography applications.
Contacting and non-contacting stylus based profilers mechanically scan the aspherical surface under test and, therefore, are slow because they measure only a few data points at a time. Slow techniques are very susceptible to measurement errors due to temperature variations during the measurement. The same limitations apply to contacting and non-contacting stylus based coordinate measuring machines.
Spherical wavefront interferometers usually require the spacing between the element generating the spherical wavefront and the aspherical surface under test to be scanned thereby increasing the measurement time for the entire surface under test thus introducing another parameter which must be measured, usually by another measurement device, and means, commonly known as stitching, for connecting the data from the various zones which fit as the spacing is scanned.
Scanning white light interferometers have many of the same limitations as spherical wavefront interferometers. Lateral and radial shearing interferometers usually measure the slope of the surface under test and thereby introduce measurement errors during the reconstruction of the surface under test via integration of the slopes. This latter type of limitation applies to differential types of profiling techniques as well.
Sub-aperture stitching interferometers introduce serious measurement errors in the stitching process. Interferometers using computer generated holograms are susceptible to errors introduced by the CGH and stray Moiré patterns. It is also difficult to calibrate, i.e., know the calibration of the CGH. Point diffraction interferometers are a class of spherical wavefront interferometers, and therefore, have many of the same limitations, as well as poor lateral spatial resolution.
None of the prior art approaches is entirely satisfactory since each involves a trade-off that places long lead times on the design of the measurement apparatus and method, requires additional fabrication, increases the difficulty of using and calibrating the measurement apparatus, decreases the accuracy and precision, and greatly increases the cost and delivery time of the aspherical optical element.
As a result of certain deficiencies in prior approaches to measuring aspheres, it is a principle object of the present invention to provide a method(s) and apparatus for high accuracy absolute measurement of aspherical surfaces or aspherical wavefronts, either the surface of the final optical part or the wavefront of the final optical lens element in transmission, or by absolutely qualifying the compensation elements for the measurement of aspheres, being either of the refractive, diffractive of reflective type, therefore enabling other, more productive methods for the measurement of the components to be produced in volume.
It is another object of this invention to measure the deviation of a given surface, such as an aspheric surface, from its nominal design shape in a direction normal to the surface.
It is another object of the present invention to provide method(s) and apparatus for measuring aspherical surfaces and wavefronts with large aspherical departures and surface slopes.
It is yet another object of this invention to provide method(s) and apparatus for measuring aspherical surfaces and wavefronts with small departures from spherical surfaces.
It is another object of the present invention to provide method(s) and apparatus for measuring aspherical surfaces and wavefronts with large diameters and clear aperture.
It is yet another object of the present invention to provide method(s) and apparatus which can be adapted to different measurement purposes and aspherical surfaces and wavefronts in an easy manner.
It is still another object of the present invention to provide method(s) and apparatus for measuring aspherical surfaces and wavefronts which can be calibrated absolutely.
It is a further object of the present invention to provide method(s) and apparatus which have highly reduced sensitivity to vibrations when measuring aspherical surfaces and wavefronts.
It is another object of the present invention to provide method(s) and apparatus which have reduced sensitivity to temperature changes in the measurement of aspherical surfaces and wavefronts.
It is yet another object of the present invention to provide method(s) and apparatus which have reduced sensitivity to air turbulence of the gas in the interferometer (measurement) cavity in measuring aspherical surfaces and wavefronts.
It is a further object of the present invention to provide method(s) and apparatus that can work with a light source of only a coherence length equal to the aspherical departure.
It is yet a further object of the present invention to provide method(s) and apparatus which can also work with wavelengths for which only point detectors exist (UV and IR-range).
It is still a further object of the present invention to provide method(s) and apparatus which automatically adjust for the spatial location from where the measurement points are sampled.
It is still another object of the present invention to provide method(s) and apparatus which can be adjusted to the spatial resolution required for the measurement.
It is yet a further object of the present invention to provide method(s) and apparatus which have reasonable speed of measurement.
It is still a further object of the present invention to provide method(s) and apparatus which compute both critical coordinates of the aspherical surface, the radial distance h and the axial distance, z, solely from interferometric measurements and not from the geometrical mapping of the detectors onto the surface.
Other objects of the invention will, in part, be obvious and will, in part, appear hereinafter when the detailed description is read with reference to the drawings.

This patent is subject to a terminal disclaimer.

Scanning interferometer for aspheric surfaces and wavefronts


A voice enhancement system is provided for improving the perceptual quality of a processed voice signal. The system improves the perceptual quality of a received voice signal by removing unwanted noise from a voice signal recorded by a microphone or from some other source. Specifically, the system removes sounds that occur within the environment of the signal source but which are unrelated to speech. The system is especially well adapted for removing transient road noises from speech signals recorded in moving vehicles. Transient road noises include common temporal and spectral characteristics that can be modeled. A transient road noise detector employs such models to detect the presence of transient road noises in a voice signal. If transient road noises are found to be present, a transient road noise attenuator is provided to remove them from the signal.

1. Technical Field
This invention relates to acoustics, and more particularly, to a system that enhances the perceptual quality of a processed voice.
2. Related Art
Many communication devices acquire, assimilate, and transfer a voice signal. Voice signals pass from one system to another through a communication medium. In some systems, including some systems used in vehicles, the clarity of the voice signal does not only depend on the quality of the communication system and the quality of the communication medium, but also on the amount of noise that accompanies the voice signal. When noise occurs near a source or a receiver, distortion often garbles the voice signal and destroys information. In some instances, noise may completely mask the voice signal so that the information conveyed by the voice signal is completely unrecognizable either by a listener or by a voice recognition system.
Noise, which may be annoying, distracting, or that results in lost information comes from many sources. Noise from a vehicle may be created by the engine, the road, the tires, or by the movement of air. When a vehicle is in motion on a paved road, a significant amount of the noise is produced when the tires strike obstructions or imperfections in the road surface. Transient road noises may be created when the tires strike obstructions such as bumps, cracks, cat eyes, expansion joints, and the like.
Transient road noises share a number of common characteristics which allow them to be identified as such. The most significant attribute of transient road noises is that they typically include a pair of related sounds or sonic events. The two sounds are generated when first the front wheels of the vehicle strike an obstruction followed by the rear wheels striking the same obstruction. The two sounds are separated in time by the length of time necessary for the rear wheels to travel the length of the vehicle's wheelbase given the vehicle's rate of travel. Furthermore, the sounds generated when the front and rear tires strike an object are broadband events having a characteristic spectro-temporal shape. Because most vehicles ride on air filled rubber tires the sounds generated when the tires strike an object have significant low frequency energy. Thus, the spectral shape is characterized by a rapid rise in signal intensity in the lower frequency ranges, a peak intensity, followed by a general tapering off in the higher frequency ranges.
These characteristics may be employed to identify the presence of transient road noises in a voice signal generated by a microphone or other source within a vehicle. Once transient road noises have been identified in a signal, steps may be taken to remove them.

Minimization of transient noises in a voice signal


A plasma reactor incorporating the invention includes a plasma chamber and one or more gas inlets for introducing an ionizable gas into the plasma chamber. A dielectric plate is positioned over an opening to the plasma chamber and above a support that holds a workpiece. An inductor is juxtapositioned to the dielectric plate and comprises multiple winding portions which evidence plural segments of increasing radii from a center of the inductor. Segments of lesser radii are arranged to reside further away from the dielectric plate than segments of greater radii, lending the inductor a truncated conical shape with respect to the dielectric plate. By modifying the pitch angle and/or radius of the plural segments, the field configuration within the chamber can be varied to accommodate different workpieces. Further, a conductive support is positioned between the dielectric plate and the plasma chamber and serves as a support for the dielectric plate, an electrostatic shield between the dielectric plate and the plasma chamber, and further provides channels for the introduction of one or more ionizable gases into the chamber.

Inductively coupled plasma (ICP) reactors use an inductive circuit element that is placed adjacent to, or inside a discharge region in order to couple energy from an RF power source to an ionizable gas. The inductive circuit element is typically a helical or spiral-like antenna structure. In certain plasma reactor systems, additional electrical reactances are used to tune the inductor, such that an electrical resonance occurs at the RF driving frequency.
When an inductive coupling element is driven in the electrical resonance condition, high potentials tend to exist on the structure which lead to a capacitive coupling to the plasma discharge. Capacitively coupled plasmas are characterized by high voltages which cause ions to be accelerated across the plasma sheath to the walls, at high energy, and can cause sputtering and heating of the walls. The prior art has reduced capacitive coupling into plasma sheaths by utilization of encompassing Faraday shields that are slotted so as to enable penetration of the inductively created energy, while shorting out the capacitive coupling.
J. Hopwood in "Review of Inductively Coupled Plasmas for Plasma Processing", Plasma Sources Science & Technology, Volume 1, 1992, pages 109-116, provides a review of a number of plasma reactor structures that are used for ICP processing. Several reactor versions employ helical inductors that are wound around a plasma chamber and are separated therefrom by slotted Faraday shields. A further version uses a planar spiral coil which is placed on a quartz window and induces energy into the plasma chamber through the quartz window.
J. Keller in "Inductive Plasmas for Plasma Processing", Plasma Sources Science & Technology, Volume 5, 1996, pages 166-172, provides further details regarding ICP reactor structures. Keller indicates that non-uniformities present in inductively induced plasmas can be reduced by increasing the turn height or width of the inductor that is used to create the plasma. Further, Keller indicates that the distance between coil turns in the middle of the coil, or where the plasma density is at a maximum, can also be increased. He further indicates that the RF fields can be reduced by an increase in the thickness of the dielectric window through which the energy is coupled. Also, he indicates that the plasma can be radially confined by multi-pole magnetic cusps and that gas injection can be improved through use of a "showerhead" so as to reduce non-uniformities in the resulting plasma sheath.
U.S. Pat. No. 5,556,521 to the Applicant herein, describes a sputter etching apparatus wherein an inductor is placed on a dielectric plate and induces a plasma within a chamber positioned beneath the dielectric plate. A contoured pocket in the dielectric plate receives the inductor and enables the creation of a high density, uniform plasma proximate to a substrate located in the plasma chamber.
ICP reactors are utilized for deposition and etching of materials, principally in the semiconductor industry. For example, plasma enhanced chemical vapor deposition (PECVD) of dielectrics and metal thin films onto large area wafers comprise standard manufacturing processes in the semiconductor industry. Further, such reactors are employed for dry etching of dielectric and metal thin films. ICP reactors are also used for manufacture of thin film transistors on large area glass substrates (e.g., for use in flat panel displays). Likewise, such reactors are used to create patterned dielectric and metal thin films on large area glass substrates.
In all such applications, it is desirable that capacitive coupling between the inductor and the plasma be minimized. As the plasma is most intense in the vicinity of the inductor assembly, there is a large ion flux directed toward the inductor. These ions are accelerated by a large sheath potential and sputter the underlying surface of the dielectric plate or window through which the inductive energy is coupled. Such sputtering forms particulates which contaminate a wafer or substrate being processed.
Because current ICP reactors operate at low pressures, the dielectric window through which the inductive energy is coupled is required to exhibit a substantial thickness so as to resist fracture due to the differential pressure that is present thereacross.
It is therefore an object of this invention to provide an improved ICP reactor wherein the structure of the inductor is arranged to enable a field configuration to be induced in the reactor chamber so as to provide a substantially uniform plasma therein.
It is another object of this invention to provide an ICP reactor which is enabled to utilize a dielectric window of relatively thin cross-section that reduces attenuation seen by energy that is inductively coupled therethrough.
It is yet another object of this invention to provide an improved ICP reactor wherein an incorporated Faraday shield substantially reduces capacitive coupling into the reactor, provides gas distribution and dielectric window support.


A method for fastening a fiber optic connector to a fiber optic cable including providing a fiber optic cable having at least one optical fiber, loose yarn serving as strength members and an outer cable sheath surrounding the loose yarn and optical fiber; providing a fiber optic connector having at least two recesses into which strength members of a fiber optic cable can be inserted; removing a portion of the outer cable sheath at an end of the fiber optic cable, thereby exposing a portion of the loose yarn at the end of the fiber optic cable; splitting the exposed portion of the loose yarn into at least two bundles; forming at least two yarn pins from the bundles; and inserting each yarn pin into a respective recess of the fiber optic connector and fastening using an adhesive. Also disclosed is the cable assembly made by the method.

The present application relates to a method for fastening a fiber optic connector to a fiber optic cable. Further, the present application relates to an assembly comprising a fiber optic connector fastened to a fiber optic cable.
Fiber optic cables like outdoor fiber optic drop cables comprise at least one optical fiber being positioned within at least one protection tube, strength members and an outer cable sheath surrounding said strength members and the or each optical fiber being positioned within the or each protection tube. The or each protection tube surrounding the or each optical fiber can be filled with gel. The strength members can be provided by rigid strength members such as glass-reinforced plastic (GRP) rods and/or by loose yarn being non-rigid.
In order to provide a connectivity function for such a fiber optic cable, a fiber optic connector has to be fastened to the fiber optic cable. When fastening a fiber optic connector to a fiber optic cable, the strength members of the fiber optic cable are fastened to an inner part of the fiber optic connector.
In case the strength members of the fiber optic cable are provided by rigid strength members like GRP rods, said rigid strength members are usually inserted into and fixed to recesses of the respective inner part of the fiber optic connector. Such a fastening solution can be used only in case the fiber optic cable comprises rigid strength members.
In case the strength members of the fiber optic cable are provided by loose yarn like loose glass yarn or loose aramid yarn, the loose yarn is crimped to the respective inner part of fiber optic connector.
However, such a crimped solution for fastening a fiber optic connector to a fiber optic cable may not provide the proper tensile strength as well as the flexing and twist performance required especially in outdoor applications.

Method for fastening a fiber optic connector to a fiber optic cable


A method of compensating for the distortion in a recording layer of a reversible thermosensitive recording medium, for which transparency of the recording layer is changeable, depending upon the temperature thereof, and the recording layer is capable of forming images and erasing the images reversibly. The distortion in the recording layer is caused by the repeated image formation by image formation means and/or image erasure by image erasing means. In this method, stress is applied to the recording layer before and/or after image formation by the movement of the recording medium relative to the image formation means, in a direction different from the direction of the application of stress in the course of a previous image formation or image erasure. Instead of the stress, thermal energy can be employed for compensating for the distortion in the recording layer.

1. Field of the Invention
The present invention relates to a method for compensating for the distortion in a recording layer of a reversible thermosensitive recording medium which comprises a substrate and a recording layer whose transparency changes depending upon the temperature of the recording layer. The distortion in the recording layer is caused while images are repeatedly formed by image formation means and/or while formed images are erased by image erasing means.
2. Discussion of Background
Recently attention has been paid to a reversible thermosensitive recording medium capable of temporarily recording images thereon and erasing the same therefrom when such images become unnecessary. As representative examples of this kind of reversible thermosensitive recording medium, there are conventionally known reversible thermosensitive recording media comprising a substrate and a recording layer in which an organic low-molecular-weight material such as a higher fatty acid is dispersed in a matrix resin such as vinyl chloride - vinyl acetate copolymer with a low glass transition temperature (Tg) of 50.degree. C. to less than 80.degree. C., as disclosed in Japanese Laid-Open Patent Applications 54-119377 and 55-154198.
These thermosensitive recording media, however, have the shortcomings that the recording layer is distorted and is caused to deteriorate while images are formed or erased repeatedly by a heating element such as a thermal head, so that image density and image contrast are significantly decreased while in use. This problem has not yet been dissolved.

Method of compensating for distortion in recording layer in reversible thermosensitive recording medium


A motor vehicle has a roof which can be adjusted between an opened and a closed position, and which has a roof skin. A rollover protection element can be moved out from an inoperative position into a protection position. For improved rollover protection, when the roof is in the closed position, the rollover protection element projects over the roof skin in the protection position.

This application claims the priority of German patent document 10 2004 062 999.4, filed Dec. 22, 2004, the disclosure of which is expressly incorporated by reference herein.
The present invention is directed to a motor vehicle having a movable roof and an extensible rollover protection element.
A motor vehicle of the above-mentioned type, known from German Patent Document DE 103 29 903 B3, has a movable roof in the form of a convertible top into whose roof skin a rear window is inserted. The motor vehicle also has a rollover protection element which is constructed as at least one rollover bar arranged behind a vehicle seat. The rollover bar, which is extensible from a lower or retracted inoperative position into an extended protective position projecting over the belt line of the motor vehicle, is held in a receiving cassette. When the roof is in the closed position, the rollover element takes up a first protective position, which is dimensioned such that the roof skin or the rear window are not destroyed. When the roof is in the opened position, the rollover protection element is moved out into a second protective position which projects over the first protective position.
One object of the invention is to provide a motor vehicle of the initially mentioned type, which affords improved rollover protection.
This and other objects and advantages are achieved by the present invention, which provides an enlarged protection area for the vehicle occupant/occupants, independently of the position of the roof (opened or closed). That is, the move-out height of the rollover protection element is maximally, selected independently of the roof position.
According to a further embodiment of the invention, the rollover protection element breaks through the roof skin in its protective position. In this case, it can be provided that the rollover protection element pushes through a non-transparent section of the roof skin. As an alternative, the rollover protection element can push through a transparent section (specifically, the rear window), or can at least partially detach or cut the rear window out of the roof skin. In a preferred embodiment, the rear window is equipped with a desired breaking point for this purpose which reliably permits a destruction of the rear window, and/or the rear window is held in the roof skin by way of a desired breaking point.
In order to favorably influence the destruction of the rear window or the penetration of the roof skin, in another preferred embodiment, the rollover protection element is equipped with a piercing element, particularly,
Finally, the movable roof may be constructed as a convertible top with a flexible convertible top material which, together with the rear window, can form the roof skin. However, it would also be possible to construct the roof as a convertible top which has a firm roof skin, for example, made of sheet metal, into which the rear window is inserted.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.

Motor vehicle with a movable roof and an extensible rollover protection element

Dr. Ing. h.c.F. Porsche Aktiengesellschaft


A transfer means has a film lightly contacting a back surface of a transfer medium and applying a transfer field thereto. The film rises rapidly with respect to a contact portion with the back surface of the transfer medium on the upstream side of the direction of movement of the transfer medium relative to the film, and slopes gently from the contact portion in a continuous curve on a downstream side of the direction of movement. The film is capable of displacement between a support and an image carrier, and contacts and disengages the transfer medium according to the presence or absence of electrostatic adsorptive force due to the supply or withdrawal of an electric current.

1. Field of the Invention
The invention relates to an image forming apparatus such as a copier, printer or facsimile machine employing a toner to form images. In particular, the invention relates to transfer technology for transferring a toner image formed on a surface of an image carrier (a photosensitive body etc.) on to a surface of a transfer medium (recording medium etc.).
2. Description of the Related Art
Generally speaking, in an image forming apparatus employing a toner to form images, it is necessary to transfer an image formed on a surface of an image carrier such as a photosensitive drum or the like onto a transfer medium such as a paper.
In order to faithfully transfer an image formed on a surface of an image carrier onto a transfer medium such as a paper so that it will reproduce well, it is necessary to prevent splashing of toner in the vicinity of a transfer portion.
In order to meet this demand with a relatively simple construction, the image forming apparatus of Japanese Patent Publication Hei. 6-202496, having the transfer structure shown in FIG. 10 has been proposed.
In FIG. 10, the reference numeral 1 indicates an image carrrier member (photosensitive drum), upon the surface of which a toner image is formed. The reference numeral 6 is a transfer medium, and 8 is a transfer medium support.
The refernce numeral 4 is a transfer charging means, comprising a conductive layer 401 made of a conductive rubber which has a shaped of a rectangular plate-like piece elongated in a direction perpendicular to the direction of conveyance of the transfer medium, and a highly conductive electrode 402 bonded to conductive layer 401 by means of a conductive adhesive and capable of applying a uniform current in the direction of thrust with respect to conductive layer 401. An abutting layer 405 having a lower coefficient of friction than that of the conductive layer 401 is provided by coating or the like on an upper surface of the conductive layer 401 contacting the transfer medium support 8. Further, a pushing member 404 (formed of a plate-like or film-like flexible member or the like) is disposed in an opposite side to that in which the abutting layer 405 of conductive layer 401 is arranged with respect to an electrical field applying member comprising the electrode 402, conductive layer 401 and abutting layer 405; and a uniform pushing force suitable for transfer is obtained in a sideways direction.
According to this kind of the image forming apparatus, a latent image is formed on the surface of the image carrying member 1, which rotates in the direction of arrow B in FIG. 10, by means of a laser beam or the like (not shown in the drawing), and this latent image forms a toner image on the surface of the image carrying member 1 by means of being developed by a developing means not shown in the drawing.
The transfer medium 6 is transported by the transfer medium support 8 in the direction of arrow A, and the toner image on the surface of the image carrying member 1 is transferred onto the transfer medium 6 by the application of an electric field by transfer charging means 4 at a transfer portion 3 (the portion contacting image carrier 1).
In the image forming apparatus described above, the shape of transfer charging means 4, positioned further downstream in the direction of conveyance of the transfer medium 6 than the transfer portion 3, is such that it is rectilinear and drops away suddenly due to the upper surface 4a and side surface 4b. Because of this, the electrical field positioned-downstream of the transfer portion changes suddenly, static electrical discharge occurs easily, and toner splash (especially splashing of the toner after transfer to the transfer medium 6) is created, and as a result, the problem arises that there is a fear that it will not be possible to carry out faithful transfer of a toner image which can be reproduced well onto the transfer medium.


An optical read/write drive such as a DVD+RW drive writes a block of new data to a read/write medium by locating an edit bit in the block of data that has already been written to the medium, and writing the block of new data to the medium, beginning or ending at the edit bit. The edit bit may be chosen to avoid errors arising from polarity conflicts between data already written to the disc and the new data. The edit bit could be, for example, a differing transition bit in a sync codeword of a modulation-encoded block.

The invention relates to optical data storage. More specifically, the invention relates to a method for writing data to an optical storage medium such as a DVD or a CD. xe2x80x9cRead/writexe2x80x9d optical discs include optical discs that allow new data to be written only once and optical discs that allow new data to be written many times. A DVD+RW disc is an example of a read/write disc that allows new data to be written many times. xe2x80x9cRead/writexe2x80x9d drives can write data to xe2x80x9cread/writexe2x80x9d optical discs. A read/write drive typically has a read mode of operation and at least one of the following write modes of operation: a write-append mode and an insert-edit mode. The write-append mode allows new data to be appended to previously written data on the read/write disc, and the insert-edit mode allows previously written data to be overwritten with new data.
When writing new data to a read/write disc, it is desirable not to create a frequency or phase discontinuity between the previously written data and the new data. The read/write drive might not be able to tolerate such discontinuities during read back of the previously written data and the new data. During readback, the discontinuities might cause problems for clocks and data recovery circuitry. Consequently, the discontinuities might render portions of the read/write disc effectively unreadable by the read/write drive.
The problems resulting from these discontinuities may be overcome by the use of xe2x80x9cedit gapsxe2x80x9d (also known as xe2x80x9csplice areasxe2x80x9d and xe2x80x9cbuffer zonesxe2x80x9d). The edit gaps separate the previously written data and the new data. A frequency or phase discontinuity might arise from an edit gap following a block of the previously written data. During readback of the previously written data and then the edit gap, the clocks and data recovery circuitry might become unstable. However, the edit gap allows sufficient time for the clocks and data recovery circuitry to recover before the newly written data is read back.
However, the use of edit gaps has its drawbacks. Storage capacity of the read/write disc is reduced because data is not stored in the edit gaps.
Moreover, the edit gaps might render portions of the read/write disc unreadable by existing read-only drives. Older read-only drives that were developed prior to newer generation read/write drives might not be capable of processing the edit gaps. Unless an existing read-only drive is somehow modified to navigate past the edit gaps, it will have difficulty reading the data stored on the read/write disc.
There is a need for a read/write drive that does not rely upon edit gaps to overcome the problem arising from discontinuities between previously written data and newly written data.
This need is met by the present invention, which may be regarded as a method of writing a block including new data to a read/write medium. The method includes locating an edit bit in a block that has already been written to the medium, and writing the new block to the disc, beginning or ending at the edit bit.
Other aspects and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.

Spliceless editing of a read/write optical medium


A flexible scabbard for securing a baton to equipment worn by a user includes a holster, a cover, and a clip. The holster and cover are made from flexible material. A strip of a first half of a hook and loop fastener wrapping around a top of the front of the holster and a first half of a snap fastener at a center of the front of a holster. The cover has a rear portion extending from the back of the holster to a forward portion having first and second security portions. A second half of the hook and loop fastener extends across the first and second security portions, with a second half of the snap fastener in the middle. When the halves of the snap fastener are engaged and the first and second halves of the hook and loop fastener are engaged, the hook and loop fastener in the security portions is orientated in a shear direction with respect to a release direction of the snap fastener.

Police and security personnel are often required to carry weapons of intermediate force such as nightsticks or batons. Batons are available in a variety of sizes, often times comprising three telescoping sections. In the retracted position, an expandable baton is only approximately one-third of its extended length.
In general, a baton scabbard may be attached to a waist belt or utility vest of the officer to enable the efficient transport and deployment of a baton. The scabbard should allow for a wide range of deployment or withdrawal directions that may be required when in pursuit or subduing a subject. However, the scabbard should also secure the baton to the officer during the officer's daily activities, such as when the officer is pursuing a subject and may be required to run, jump, climb over walls or fences or move quickly up or down stairs.
Scabbards may be made of rigid plastic, providing various means, such as a spring or a compression fit, for securely engaging a baton in the scabbard. However, flexible fabric scabbards may be desired for comfort or other reasons. Accordingly, there is a need for a flexible scabbard that secures a baton against loss while enabling quick deployment when needed.

Secured flexible case for police or military baton


A channel information feedback method for multi-antenna system, and a wireless communication device using the same method are provided. The proposed method could reduce feedback overhead for multiple-input multiple-output (MIMO) wireless channel information, and is based on compressive sensing technique. Prior to sending back channel information, a receiver estimates the channel and multiplies the vectorized channel with a random matrix to generate compressed feedback content. Upon receiving the compressed feedback content at a transmitter, the channel information could be restored with signal recovery algorithms of compressive sensing technique. In the other embodiment, the proposed method further adaptively adjusts compression ratio of the compressed feedback content in accordance to the prevailing channel quality. Further, for slow-varying MIMO channels, there is proposed another channel information feedback method which switches between a fixed sparcifying-basis and a signal-dependent sparcifying-basis.

Many recent researches have found that by equipping transmitters of wireless communication systems with large antenna arrays, huge array gain can be attained and high data rate can be achieved with very low transmission power. Such communication scheme, known as Massive-MIMO, is a promising technique for future wireless communication systems due to its high power efficiency. However, the benefits of Massive-MIMO are mainly attributed to the availability of channel state information (CSI) at the transmitter. Many MIMO techniques, including beamforming, channel inversion, adaptive power/bit allocations, and interference alignment, require the transmitter to possess certain spatial channel information. Hence, most of the relevant research works in this context has focused on time-division duplex (TDD) schemes as channel information can be acquired by the transmitter by exploiting channel reciprocity. Additional feedback mechanism is required for frequency-division duplex (FDD) systems, and apparently feedback overhead is a formidable challenge for Massive-MIMO due to the large number of antennas. In order to realize Massive-MIMO under FDD mode, a more efficient channel information feedback mechanism for Massive-MIMO should be designed.
Most of the prevalent MIMO communication standards, such as LTE-A and WiMAX, employ codebook-based approaches to reduce feedback burdens. A codebook which consists of multiple entries should be pre-configured and stored at both the transmitter and the receiver. Each index of the codebook maps to a quantized version of MIMO spatial channel information. Therefore, feedback volume can be tremendously reduced by merely sending the index of the codebook entry that provides the most appropriate representation of the current channel structure.
Codebook-based quantization approach may work properly for moderate MIMO systems with two to eight antennas. For Massive-MIMO with numerous antennas, however, the codebook size has to be expanded extensively to capture all prospective spatial channel structures. This makes codebook design much more difficult. Apparently, expansion of codebook size also leads to heavier feedback overhead. On the other hand, the intrinsic quantization errors of codebook-based approach may not be acceptable for massive MIMO-based green radio techniques that aim to save transmission power via precise beamforming.

Channel information feedback method and wireless communication device using the same

Industrial Technology Research Institute


Acetylacetone and an aqueous nitric acid are included in a solution in which organic metal compounds of metals constituting a ferroelectric in an organic solvent thereby forming a ferroelectric film formation solution. The solution is applied to a substrate, followed by drying and baking to obtain a ferroelectric film. As a consequence, even when forming a ferroelectric film such as a PZT or PLZT film containing a II group element in the periodic table, a stable ferroelectric film formation solution which prevents neither crystallization nor gelation and is reduced in a change with time in the viscosity thereof can be obtained. A ferroelectric film which contains a II group element and has excellent ferroelectric properties can be thus produced with ease.

The present invention relates to a ferroelectric film formation solution for forming a ferroelectric film on a substrate and a method for forming a ferroelectric film using the solution. Particularly, the present invention relates to a ferroelectric film formation solution which has neither crystallization nor gelation when forming a ferroelectric film containing a II group element in the periodic table such as Mg, Ca, Sr, or Ba and which can form a stable ferroelectric film on a substrate such as sapphire, titanium, or platinum. The present invention also relates to a method for forming a ferroelectric film using the ferroelectric forming solution.
Lead zirconate titanate (PZT) which is a complex oxide of Pb, Zr, and Ti and lead lanthanum zirconate titanate (PLZT) which is a complex oxide of Pb, Zr, Ti, and La have high dielectric capability, ferroelectricity, piezoelectric effect, and pyroelectricity. The thin films of these complex oxides are therefore used for semiconductor memories such as a DRAM (memories using paradielectrics with high dielectric constant such as (Ba,Sr)TiO3) and FRAM (memories using ferroelectrics such as PZT), capacitors, sensors, and actuators.
In recent years, ferroelectrics containing a small amount of Nb, Fe, Mn, Al, Sn, Bi, Sb, Ba, Ca, Sr, and the like have been studied to improve the characteristics of PZT or PLZT. These ferroelectrics are reported, for example, in Journal of American Ceramic Society, Vol 77, pages 2620-2624 (1994), Japanese Patent Application Laid-Open (JP-A) No. H1-260870, and the like.
Generally, an organic metal compound such as an alkoxide of a metal which is a component of ferroelectrics is reacted in an organic solvent. Then a chelating agent is added to the mixture to improve the stability of a solution, or the mixture is hydrated. And such a solution is widely used for forming the ferroelectrics.
In such a preparing method, however, a solution for forming a thin film of PZT or PLZT containing a II group element in the periodic table such as Mg, Ca, Sr, or Ba tends to crystallize or gel. Even when these phenomena are not produced, the viscosity of the solution changes with time. If the viscosity of the solution increases, the solution cannot be uniformly applied. Also, in the case where the viscosity of the solution increases or decreases, the film thickness when a film is formed varies, giving rise to the problem that it is very difficult to prepare a solution for forming a stable thin film.
An object of the present invention is to provide a stable ferroelectric film formation solution which prevents crystallization or gelation even when forming a ferroelectric film such as PZT or PLZT containing a II group element in the periodic table and which is reduced in a change in the viscosity of the solution with time.
Another object of the present invention is to provide a method for forming a ferroelectric film using the ferroelectric film forming solution.
The present inventors have conducted earnest studies to obtain a stable raw material solution, when forming a ferroelectric film by applying the raw material solution of a ferroelectric followed by drying and baking, which is used for forming the aforementioned ferroelectric film of PZT or PLZT or the like containing a II group element in the periodic table and which neither crystallizes nor gels in a solution condition and is reduced in a change with time in the viscosity of the solution. As a result, the present inventors have found that a stable solution for forming a ferroelectric film of PZT or PLZT or the like containing a II group element in the periodic table which solution neither crystallizes nor gels and is reduced in a change with time in the viscosity of the solution can be obtained by adding acetylacetone and an aqueous nitric acid solution to a solution prepared from an organic solvent and an organic metal compound such as an alkoxide of a metal which is a component of PZT or PLZT containing a II group element in the periodic table.
Accordingly, a ferroelectric film formation solution according to the present invention comprises acetylacetone and an aqueous nitric acid solution in a solution prepared from an organic solvent and an organic metal compound of a metal constituting a ferroelectric.
In this case, the solution prepared from an organic solvent and an organic metal compound means a solution comprising an organic metal compound and an organic solvent, for example the solution in which an organic metal compound is dissolved in an organic solvent or a reacted product is dissolved in an organic solvent, which reacted product is produced by an alcohol exchange reaction (a reaction between an organic metal compound and an organic solvent), a complex alkoxide formation reaction (a reaction between an alcohol exchange reaction product and the organic metal compound and a reaction between organic metal compounds), or coordination of the organic solvent to a metal atom.
Particularly when the aforementioned organic metal compound contains an organic metal compound of a II group element in the periodic table, crystallization or gelation tends to be caused. In the present invention in which acetylacetone and an aqueous nitric acid solution is added to the ferroelectric film forming solution, however, crystallization or gelation can be prevented, which is particularly preferable.
As the II group element, at least one element selected from the group consisting of Mg, Ca, Sr, and Ba may be used.
It is particularly preferable when the aforementioned organic metal compound comprise organic metal compounds respectively containing titanium, zirconium, lanthanum, and lead constituting lead zirconate titanate (PZT) or lead lanthanum zirconate titanate (PLZT), and further an organic metal compound of a II group element in the periodic table to prevent crystallization or gelation which is easily caused in these organic metal compound.
A method for forming the ferroelectric film of the present invention comprises (a) a step of preparing a solution containing an organic solvent and an organic metal compound of a metal constituting a ferroelectric and mixing acetylacetone and an aqueous nitric acid solution with the above solution to prepare a ferroelectric film formation solution, (b) a step of applying the ferroelectric film formation solution to the surface of a substrate, and (c) a step of baking the applied solution after it is dried.
It is particularly preferable when an organic metal compound of a II group element in the periodic table is contained in the above solution to form a ferroelectric film containing the II group element in the periodic table, because crystallization or gelation is not caused and a stable ferroelectric film containing the II group element in the periodic table can be formed.
When organic metal compounds respectively containing titanium, zirconium, and lead which constitute lead zirconate titanate (PZT) are used and further an organic metal compound of a II group element in the periodic table is added, there is obtained a PZT thin film to which the II group element is added.
When organic metal compounds respectively containing titanium, zirconium, lanthanum, and lead which constitute lead lanthanum zirconate titanate (PLZT) are used and further an organic metal compound of a II group element in the periodic table is added, there is obtained a PLZT thin film to which the II group element is added.

Solution for forming ferroelectric film and method for forming ferroelectric film


A semiconductor storage device includes a non-volatile first memory, a second memory that includes a first area for recording data to be recorded in the first memory and a second area for recording data read from the first memory, and a memory controller that controls the first memory. The memory controller acquires event logs for each event, adds a footer that specifies the data start position of the event log to an end of each of the event logs, sequentially records the event logs to which the footer is added in an order of occurrence of the event from a low address toward a high address of the first area, stores a plurality of the event logs which are recorded in the first area and has the footer added to the plurality of the event logs in the first memory, and sequentially reads the plurality of event logs stored in the first memory in an order from a latest event log, based on content of the footer added to each event log, to sequentially record the read event logs from a low address toward a high address of the second area in a read order of the read event logs.

A semiconductor storage device generates a log (event log) relating to an event thereof each time an event occurs and stores the generated log in a storage area in a readable manner. When a log read request is received from a host, the semiconductor storage device is configured to generate a Reporting Context from event logs stored in the storage area and transmit a log page in which the event logs are arranged in the latest order to the host. Here, the Reporting Context is information indicating a configuration of the log data generated by a controller. When transmitting a log page to the host, the requested event logs are required to be arranged in the latest order.
A semiconductor storage device stores data in a storage area in a certain amount of recording units. Therefore, the semiconductor storage device stores data in a buffer until the stored data becomes a recording unit and transfers the stored data of the recording unit to the storage area. Since an event log is generated each time an event occurs, when the log is stored in the storage area for each event type, storing timing will be changed depending on types of the event. Accordingly, the semiconductor storage device stores all event logs in the order of occurrence regardless of the types of the event. However, since a log page in which event logs are arranged in the latest order is requested to be transmitted, the semiconductor storage device may not satisfy this request when the stored event logs are provided as is.

Semiconductor storage device and control method thereof


A control device for a vehicle camera may include: a wiper relay connected to a multi-function switch to operate a vehicle wiper at a predetermined cycle; a camera controller connected to the wiper relay, and synchronizing the operation cycle of the wiper with an imaging cycle of the vehicle camera such that the vehicle camera images the front of the vehicle according to the operation period of the wiper; and an image filter connected to the camera controller, estimating the position of the wiper from edge information of the images taken by the camera, and searching and removing the wiper in the taken images.

Field of the Invention
Exemplary embodiments of the present invention relate to a controlling device and method of a vehicle camera, and more particularly, to a controlling device and method of a vehicle camera, which is capable of handling a situation in which it is difficult acquire an image due to a wiper operation of the vehicle in case of bad weather.
Description of the Related Art
When a vehicle camera takes images while a wiper is operated due to an external factor such as rain or snow, the quality of the images may be degraded by interference of the wiper operation or the rain or snow in the images.
The operation of the conventional vehicle camera is set in a fixed mode or an automatic mode (exposure, gain and the like) depending on external illuminance. Thus, when the above-described external factor occurs, the performance of a front-view camera system cannot be stably secured.
In particular, when an external factor occurs in the fixed mode, the operation of an intelligent driver assistance system may be limited in a situation where the stability of a driver is required due to the operation of the wiper.
In the automatic mode, the camera may be controlled depending on the external illuminance, and thus provide an image of which the quality is improved more than in the fixed mode. Under the condition where the external illuminance is hardly changed, however, the camera may not properly handle a situation in which an external factor such as the amount of rain or the operation speed of the wiper is changed.
From the above-described point of view, Japanese Patent Laid-open Publication No. H08-72641 has disclosed an image recognizing device for vehicle, which includes an imaging control unit to prevent the reception of image signals during a period of time corresponding to the operation of a wiper, in order to secure the precision of image information. In such an image recognizing device, however, since the imaging control unit prevents the reception of image signals during the period of time corresponding to the operation of the wiper, the input image information is inevitably limited.

Controlling device and method of vehicle camera


Disclosed is a method of making 1,1'-sulfonylbis[3-nitro-5-(trifluoromethyl) benzene] by reacting dibenzotrifluoride sulfide with at least four equivalents of fuming nitric acid and at least four equivalents of fuming sulfuric acid at a temperature below 20.degree. C., until the sulfide link is oxidized to a sulfone link, then raising the temperature to above 20.degree. C. until the reaction is complete. Also disclosed is the preparation of 1,1'-sulfonylbis[3-nitro-(5-trifluoromethyl) benzenamine] by reducing the benzene compound.

This invention relates to a method of making 1,1'-sulfonyl-bis (3-nitro-5-trifluoromethyl) benzene by reacting 1,1'-thiobis[3-(trifluoro-methyl) benzene] with fuming nitric acid and fuming sulfuric acid at a temperature below 20.degree. C., followed by raising the temperature to about 30.degree. to about 80.degree. C.
In co-pending application filed of even date by Jeffrey S. Stults and Henry C. Lin, titled "Novel Bis-M-Benzotrifluoride Compounds," Ser. No. 394,990, now abandoned in favor of continuation in part application Ser. No. 594,479, filed Oct. 9, 1990, herein incorporated by reference, there is disclosed the compound 1,1'-sulfonylbis[3-bis-nitro-5-(trifluoromethyl) benzene] (SBB), and the compound 1,1-sulfonylbis[3-nitro-5-(trifluoromethyl) benzenamine], which is made by reducing SBB. That application discloses that SBB can be made by first reacting benzotrifluoride meta-chloride with sodium sulfide to prepare 1,1'-thiobis[3-(trifluoromethyl) benzene]. In the next step, the benzotrifluoride sulfide is oxidized to the sulfone using an oxidizing agent such as hydrogen peroxide in acetic acid. Finally, the sulfone is nitrated using a mixture of fuming nitric acid and fuming sulfuric acid. While SBB can be prepared in good yield using that three-step process, a simpler and more direct process would be desirable.

Method of making 1,1'-sulfonylbis[3-nitro-5-(trifluoromethyl)benzene]


A liquid crystal device includes a first substrate, a second substrate, a liquid crystal layer disposed between the first substrate and the second substrate, a first alignment layer disposed on the liquid crystal layer side of the first substrate, and a second alignment layer disposed on the liquid crystal layer side of the second substrate. At least one of the first alignment layer and the second alignment layer is made of an inorganic porous film having pores exposed at its surface and grooves to control the orientation of the liquid crystal layer.

1. Technical Field
The present invention relates to a liquid crystal device including alignment layers controlling the orientation of the liquid crystal molecules, a method for manufacturing the liquid crystal device, and an electronic apparatus including the liquid crystal device.
2. Related Art
Liquid crystal devices are used as, for example, light valves of liquid crystal projectors. A liquid crystal device includes a pair of substrates and a liquid crystal layer disposed between the substrates with a sealing member. Alignment layers controlling the orientation of liquid crystal molecules constituting the liquid crystal layer are disposed on the liquid crystal layer sides of the substrates. The alignment layers are made of an organic film, such as polyimide film.
In the liquid crystal device having such a structure, unfortunately, moisture, impurity ions, and polar materials permeate into a space between the substrate through the sealing member or the like. This accelerates the degradation of the alignment layers and the liquid crystal layer by strong light from the light source of the liquid crystal device, for example, a liquid crystal projector. In addition, those impurities reduce the hold capacitance and further reduce the resistance to increase the current, thus causing display failure. Accordingly, for example, JP-A-3-233428 discloses a technique in which porous inorganic particles are dispersed in the alignment layers to absorb moisture, impurity ions and polar materials.
This technique, however, cannot establish a satisfying alignment of the liquid crystal molecules around the inorganic particles. Consequently, problems, such as display failure, undesirably occur. For example, when black is displayed, light leakage occurs. Particularly in liquid crystal projectors, such display failure is conspicuous in enlarged images. In addition, the thickness of the liquid crystal layer is increasingly reduced and finally to a degree smaller than the particle size of the inorganic particles. Consequently, inorganic particles cannot be used.

Liquid crystal device, method for manufacturing the same, and electronic apparatus including the same


In operation, a standard cell library having diode place-holders (16) associated with standard cell inputs (12) is used to design a standard cell-based semiconductor device. Each standard cell in the standard cell-based semiconductor device is analyzed to determine if its standard cell inputs (12) will be connected to a conductive element (18) during processing that can accumulate a charge. When a conductive element (18) that can accumulate charge is identified, the diode place-holder (16) associated with its standard cell input (12) is replaced with a diode (16).

Antenna diodes are diodes that are inserted in integrated circuit layouts to protect against electrostatic discharge (ESD). ESD may be caused by accumulation of charge on a metal net connected to input gates, or inputs, during manufacturing. These gates often have thin dielectric layers which are damaged by the ESD.
The ESD through a gate dielectric occurs when there is no lower resistance path for the charge to follow. For example, when a metal net that connects to the gate also connects to a drain or source of the integrated circuit, the charge is allowed to dissipate to the diffusion area of the drain or source which provides a lower resistance path, thereby protecting the gate dielectric from the charge. Therefore, antenna diodes are connected to metal lines that otherwise during manufacturing process would be connected to a gate but not to the substrate.
The use of antenna diodes is also used with standard cell libraries. Standard cell libraries include individual standard cells implementing various logical functions. Generally, each standard cell has at least one standard cell input for receiving a signal from another standard cell or external source. These standard cells are pre-designed, and used as a "building blocks" to create a larger standard cell-based design.
At the time a standard cell is designed, it is unknown what a standard cell input will ultimately be connected to. Therefore, it cannot be determined whether an antenna will ultimately be needed because the larger design is not known. Therefore, antenna diodes are connected to each standard cell input gate to assure ESD damage does not occur during manufacturing.
Adding antenna diodes to each standard cell input has several disadvantages. The first is an increase in capacitance associated with the standard cell input. This increase in capacitance results in slower operation and increased current consumption. Second, the diode results in additional current drain. The increased current consumption results in increase power consumption. Therefore, a standard cell library that limits the number of antenna diodes would be desirable.

Semiconductor device using diode place-holders and method of manufacture thereof


Device and methods of forming a device are disclosed. The method includes providing a substrate defined with a memory cell region. A first upper dielectric layer is provided over the substrate. The first upper dielectric layer includes a first upper interconnect level with one or more metal lines in the memory cell region. A second upper dielectric layer is provided over the first upper dielectric layer. The second upper dielectric layer includes a via plug coupled to the metal line of the first upper interconnect level. An alignment trench which extends from a top surface of the second upper dielectric layer to a portion of the second upper dielectric layer is formed. Various layers of a MTJ stack are formed over the second upper dielectric layer. Profile of the alignment trench is transferred to surfaces of the various layers of the MTJ stack to form a topography feature which serves as an alignment mark. The various layers of the MTJ stack are patterned to form a MTJ element using the alignment mark visible in top surface of the various layers of the MTJ stack to align the memory element to the underlying via plug.

Magnetic random access memory (MRAM) is a non-volatile random access memory which gains popularity in recent years as potential replacement for dynamic random access memory (DRAM), static random access memory (SRAM) and flash. MRAM, for example, includes magnetic tunnel junction (MTJ) element which uses magnetic polarization to store information. MRAM device, for example, includes MTJ stack layers having a plurality of magnetic layers. The MTJ stack layers are generally connected to interconnects in the interlevel dielectric (ILD) layer. The various MTJ stack layers, however, are not transparent to light. Thus, when the various MTJ stack layers are patterned using lithography and etch techniques, the patterned MTJ stack layers may not be aligned to the underlying interconnect structures due to non-transparent metal layers of the MTJ stack and thus fail to couple to the underlying interconnect structures. This may render the MRAM device inoperable.
Accordingly, it is desirable to provide reliable and cost effective techniques to properly align the various MTJ stack layers with underlying interconnect structure to ensure electrical connection for the MRAM device.

Magnetic tunnel junction stack alignment scheme


A modular electronic assembly includes a chassis, a housing supported by the chassis having an access opening through a first wall of the housing, a removable access panel or releasable member at least partially covering the opening, and a midplane supported by the chassis and slidably removable from the chassis through the opening when the housing is mounted on the chassis. A method of constructing a modular electronic assembly is also disclosed.

Assemblies for supporting a plurality of electrical components and connecting them to various power supplies, inputs, outputs and/or to one another are well known. The electrical components are often modular and can be individually connected to and removed from the assembly. Such assemblies may be referred to, for example, as electrical cabinets or racks and generally comprise a structural frame or chassis that supports the electrical components. The assembly may be at least partially surrounded by a housing to protect the electrical components.
The housing, in some instances, may comprise individual panels secured to the chassis. In other cases, a housing may include structural supports integrated therewith and lack a distinct chassis. As used herein, "chassis" will generally refer to structural elements of an electronic assembly and "housing" will refer to elements provided primarily for protecting or covering the electronic modules whether these elements are separately provided or integrally formed.
It is also known to provide such assemblies with a midplane. A midplane is frequently a printed circuit board (PCB) having a plurality of connectors connectable to the electronic modules supported by the assembly. A midplane is generally provided toward the middle of an assembly and often includes electrical connectors on front and rear surfaces thereof so that modules can be connected to both sides.
Typical assemblies include a chassis that is constructed around a midplane, which essentially makes the midplane an integral part of the chassis. This is especially true in the case of "dual bay" or "multi-bay" assemblies which are arranged to support multiple levels of electronic modules stacked vertically and thus have at least two bays on their front and rear sides. If a midplane requires repair or if an upgrade to the midplane is needed, the chassis must be disassembled to a significant degree to access the midplane. This is often difficult to do at a site where the assembly is installed because it may be difficult or impossible to properly realign the midplane with the chassis when it is reinstalled in the assembly. Moreover, employees or contractors skilled in assembling sheet metal chassis may not be adept at handling printed circuit boards, and a printed circuit board may be damaged when a chassis is assembled around it. Electrostatic discharge, for example, can damage the PCB if care is not taken during chassis assembly.
It would therefore be desirable to provide an electrical assembly to which a midplane may be added after chassis assembly is complete and which allows for the easy removal and replacement of a midplane.

Electronic assembly with modular midplane


A dual-port memory device provides for a memory array which is divided approximately in half. Between the two halves of the array, a bit line crossover scheme is provided which minimizes stray capacitance and cross-coupling capacitance between bit lines for the two different ports. A bit line layout plan which minimizes such capacitances causes the data for one of the ports to be inverted in one-half of the array. When data from this half of the array is read or written by such port, the data being read or written must be inverted.

1. Field of the Invention
The present invention relates generally to semiconductor integrated circuit devices, and more specifically to dual port memory devices.
2. Description of the Prior Art
Computer systems utilize cache memories to enhance system performance. A data cache contains the cached data, and a cache tag memory contains the addresses of data stored in the cache. A processor, when making a memory access, accesses the desired memory location through the cache. If the desired location is already in the cache, access is complete. If it is not, the memory location is fetched from main system memory and loaded into the cache.
The speed of the integrated circuit devices used in the cache are important. The cache tag memory must provide a hit or a miss signal for every memory access by the processor. If the cache tag memory is slightly slow, the performance of the entire system suffers.
As is known in the art, one technique to improve the operating speed of integrated circuit devices is to reduce or balance stray capacitances. Memories have relatively long bit lines which contribute significantly to such capacitances. Good device design can help minimize such capacitances, but the nature of a memory device causes inevitable problems. Therefore, balancing of bit lines in a memory device layout is important.
No successful design has previously been done for a dual port cache tag memory device. In such a device, the capacitances for two sets of bit lines must be considered. In addition to stray capacitances, coupling capacitances between bit lines for the two ports can adversely impact device performance. In a dual port cache tag memory, in which speed is important, the extra problems caused by the extra bit lines can be significant.
It would therefore be desireable to provide a layout and design for a dual port memory device which minimized problems caused by stray and cross coupling capacitances. Such design preferably provides significantly improved performance without adding undue complication to the overall device design. It is desirable that the dual port memory device design is suitable for use in cache tag memory integrated circuit devices.

Integrated circuit dual-port memory device having reduced capacitance


A trailer hitch guide device may include a guide ramp, a guide ramp release, a hitch guide base, and a bottom metal layer. The trailer hitch guide device may enable a person to couple a trailer and a towing vehicle with ease.

A trailer may include an unpowered vehicle, which may be adapted to be pulled or towed by a powered vehicle. A trailer hitch may include a tow ball and coupler configuration, a tow pin and jaw configuration, or a pintle hitch. A trailer hitch with a tow ball and coupler configuration may include a tow ball attached to the chassis of a vehicle. One advantage of a tow ball and coupler configuration may include allowing a trailer to swivel and/or articulate.


This invention is method of producing a creping cylinder adhesive comprising: contacting a dry form PVOH with a liquid form PVA at a temperature of less than 80° C., maintaining the PVOH and PVA at a temperature of between 90-95° C. until the PVOH is completely dissolved into a medium, and allowing the medium to cool to below 80° C.

This invention, relates to PVA compositions, useful in creping tissue paper. The desired properties of tissue paper, including softness, bulk, flexibility, and absorbency, are achieved by a process known as "creping". Typically, paper creping takes place on a heated creping cylinder (often referred to as a "Yankee Dryer") by the actions of a doctor blade. Creping is performed by transferring a wet paper sheet on to the creping cylinder's surface after it has been largely dewatered at a pressure roll nip. When first transferred, the non-water component of the sheet is about 35-90% of its mass. The sheet is further dried on the hot creping cylinder to achieve a non-water consistency of about 90-98% of its mass. The sheet then is removed from the creping cylinder by impact with the doctor blade. The mechanical action of the doctor blade results in a disruption of the fiber-fiber bonds in the sheet and forms microfold-structures within the sheet. These disruptions and microfold-structures produce many of the desired properties of tissue paper.
In order to crepe, the paper sheet must adhere to the surface of the creping cylinder. The adhesion is accomplished by the use of an adhesive coating applied to the creping cylinder. The most common adhesive coatings are synthetic polymers such as polyaminoamides, polyamides, polyamines, polyvinyl alcohols, polyvinyl acetates, polyacrylamides and polyethers. Various low molecular weight compounds are used to modify the coating properties. In order to function properly, an adhesive coating must have adequate: (i) uniformity, (ii) durability, and (iii) softness.
Uniformity of the coating is important for a few reasons. First, it affords consistent creping that affects the quality of the produced sheet. Also, it prevents direct exposure of the creping cylinder surface to the blade, which can lead to premature wear of the cylinder and the blade.
Durability is a characteristic of how well the coating remains on the creping cylinder's surface, particularly at the pressure roll nip. It is important because, if the coating is easily washed off, it exposes the creping cylinder and leads to excessive wear on the blade and the cylinder surface.
Softness is also important, because a coating that is too hard causes blade chatter. Blade chatter causes blade wear and non-uniform creping. Therefore, a coating which is uniform, durable, and soft is ideal.
The art described in this section is not intended to constitute an admission that any patent, publication or other information referred to herein is "Prior Art" with respect to this invention, unless specifically designated as such. In addition, this section should not be construed to mean that a search has been made, or that no other pertinent information, as defined in 37 CFR §1.56(a), exists.