The invention relates to a laser system for the ionization of a sample by matrix-assisted laser desorption in mass spectrometric analysis. The invention consists in providing an adjustable laser system which, in one setting, generates a single intensity peak on the sample and, in another setting, a multiplicity of intensity peaks, with the half-width, intensity, spatial arrangement and/or degree of spatial modulation of the single intensity peak and/or the intensity peaks being adjustable.

In the last 10 to 15 years, two methods for the soft ionization of biological macromolecules have prevailed in mass spectrometric analysis: matrix-assisted laser desorption/ionization (MALDI), and electrospray ionization (ESI). The biological macromolecules to be analyzed are termed analyte molecules below. With the MALDI method, the analyte molecules are generally prepared in a solid matrix on the surface of a sample support, whereas with the ESI method they are dissolved in a liquid. Both methods have a considerable influence on the mass spectrometric analysis of biological macromolecules in genomics, proteomics and metabolomics; their inventors were awarded the Nobel prize for chemistry in 2002.
In a prepared MALDI sample, there are 103 to 105 times as many matrix molecules as there are analyte molecules, and they form a polycrystalline matrix in which the analyte molecules are embedded, isolated in the interior of the crystals or at their grain boundaries. The prepared MALDI sample is irradiated with a short-time laser pulse, which is strongly absorbed by the matrix molecules. The pulsed laser irradiation means that the matrix is explosively transferred from the solid state into the gaseous phase of a vaporization cloud (desorption). The analyte molecules are usually ionized by being protonated or deprotonated in reactions with matrix molecules or matrix ions, the analyte ions being predominantly singly charged after leaving the vaporization cloud. The degree of ionization of the analyte molecules is only some 10−4. The term soft ionization is used when an analyte molecule is transferred separately into the gaseous phase and ionized without undergoing any bond breakage.
Despite the linear absorption by the matrix, matrix-assisted laser desorption/ionization is a nonlinear process, which for pulsed laser radiation with a duration of a few nanoseconds only starts above an intensity threshold of around 106 watts per square centimeter. For soft ionization, the maximum intensity lies at an upper limit of approximately 107 watts per square centimeter. With a typical duration of around ten nanoseconds, the stated intensity limits result in a fluence of the laser radiation between 10 and 100 millijoules per square centimeter.
The MALDI process is complex and affected by numerous factors, some of which are interdependent. Since the MALDI method was first published in 1988, many parameters have been investigated and varied. In spite of this, the processes in the matrix and in the vaporization cloud, which lead to the ionization of the analyte molecules, are still not completely understood and are still under intense research (K. Dreisewerd, Chem Rev. 103 (2003), 395-425: "The Desorption Process in MALDI").
The chemical parameters of the MALDI process, for example the matrix substances themselves, the concentration ratio between matrix and analyte molecules, and the preparation conditions, have been comprehensively researched. For analyte molecules of different chemical substance classes. such as proteins or nucleic acids, over one hundred different chemical matrix substances are known, such as sinapic acid, DHB (2,5-dihydroxy benzoic acid), CHCA (α-cyano-4-hydroxy cinnamic acid) or HPA (3-hydroxypicolinic acid). The matrix substances exhibit strong absorption in the wavelength range between 330 and 360 nanometers. A MALDI sample can be prepared in a number of different ways, for example with "dried droplet" preparation or thin layer preparation. In "dried droplet" preparation, the matrix substance is dissolved together with the analyte molecules in a solvent, applied to a sample support, and then dried slowly in air. In thin layer preparation, on the other hand, the matrix substance without analyte molecules is dissolved in a volatile solvent such as acetone or acetonitrile, and applied to the sample support. Compared with "dried droplet" preparation, the volatile solvent evaporates very quickly and facilitates the creation of a thin, homogeneous matrix layer. A solution with analyte molecules is then applied to the thin matrix layer, causing the latter to be partially dissolved again, and the analyte molecules are integrated into the matrix during the subsequent drying. Whereas in thin layer preparation a homogeneous MALDI sample with microcrystals is produced, in "dried droplet" preparation larger crystals are formed and the surface of the MALDI sample shows a distinct morphology with different sample thicknesses.
As far as the physical parameters of the MALDI process are concerned, until now the temporal duration of the laser pulses, the intensity in the laser focus, and the wavelength of the pulsed laser radiation have chiefly been considered.
Nowadays, commercially available mass spectrometers with MALDI mainly use pulsed laser systems in the ultraviolet spectral range (UV). A number of laser types and wavelengths are available: nitrogen laser (λ=337 nm), excimer lasers (λ=193 nm, 248 nm, 308 nm), Nd:YLF laser (λ=349 nm), and Nd:YAG laser (λ=266 nm, 355 nm). Only the nitrogen laser and the Nd:YAG laser at a wavelength of 355 nanometers are of commercial interest for the MALDI method far and away the most frequently used. The laser medium of the nitrogen laser is a gas, whereas with the Nd:YAG laser it is a YAG (yttrium aluminium garnet: Y3Al5O12) crystal doped with neodymium ions. With the Nd:YAG laser, the strongest laser line, at a wavelength of 1064 nanometers, is turned into the stated wavelengths in nonlinear optical crystals. The duration of the laser pulses used in the MALDI method is typically between 1 and 20 nanoseconds in the UV. In the academic field, however, pulse durations in the region of picoseconds have also been used.
For the MALDI method, laser systems which emit in the infrared spectral region (IR): Er:YAG (λ=2.94 μm) and CO2 (λ=10.6 μm) are also occasionally used in the field of research. Whereas with the UV-MALDI method the matrix molecules are supplied with energy via excited electronic states, in the IR-MALDI method molecular oscillations of the matrix molecules are excited. The pulse duration of the IR laser systems in the IR-MALDI method are between 6 and 200 nanoseconds. In contrast to the UV-MALDI method, both solid matrices and liquid matrices, for example glycerine, are used in the IR-MALDI method.
The laser systems used in the MALDI method differ not only in their wavelength but also in their spatial beam profile. For solid-state lasers such as the Nd:YAG laser or the Er:YAG laser, the laser medium is a crystal doped with ions. The laser medium is located in an optical resonator, which ensures that the spatial beam profile consists of one transverse fundamental mode or a few transverse beam modes. The radial intensity distribution of the transverse fundamental mode corresponds to a Gaussian function and is rotationally symmetric to the direction of propagation of the laser radiation. A laser beam like this can be focused to a minimum diameter which is limited only by the diffraction.
The nitrogen laser at a wavelength of 337 nanometers is by far the most frequently used type of laser in the MALDI method, this wavelength being the most intensive laser line of the nitrogen laser. The laser medium used is gaseous nitrogen, which is excited by means of an electrical discharge between two electrodes elongated along the beam direction. Since the most intensive laser line exhibits a high amplification, a laser pulse can remove the population inversion of the energy states even if it passes along the electrodes only once. Even when using a resonator with mirrors, many transverse beam modes are superimposed in the beam profile of the nitrogen laser, with the result that the minimum diameter of a laser focus in commercial nitrogen lasers at a wavelength of 337 nanometers is only around three micrometers. The typical diameter of the area irradiated in MALDI applications is around 20 to 200 micrometers. The beam profile has a rectangular shape at the front side of the two electrodes, the geometrical dimensions of the beam profile being determined by the width and spacing of the discharge electrodes. The intensity distribution inside of the rectangular shape is approximately homogenous (i.e. flat-top beam profile). The repetition rate of the laser pulses in the nitrogen laser is limited to around 100 hertz unless provision is made for a rapid gas exchange. Nitrogen lasers with a typical repetition rate of 50 hertz are used for MALDI applications.
In practice, the electrical gas discharge in the nitrogen laser is not the same pointing the discharge volume between the electrodes generating a spatially inhomogeneous amplification profile. The inhomogeneous amplification does not even out during the short time the laser is in action, but instead transfers to the intensity distribution of the beam profile of the nitrogen laser. The nitrogen laser thus has a spatially modulated flat-top beam profile with intensity maxima and minima, which is imaged onto the sample or focused onto it. These inhomogeneities being inherently present in the beam profile of the nitrogen laser lead to an intensity distribution of the laser radiation on the sample being spatially modulated and always exhibiting a multiplicity of intensity peaks.
The pulsed solid-state lasers used until now in the MALDI method usually have a beam profile which comes very close to a single Gaussian beam mode. If a pulsed laser beam is focused or imaged onto the sample, then at the location of the sample there is a Gaussian intensity distribution with a single intensity peak. The width of an intensity peak is generally given by the so-called half-width. In the region of the half-width, the intensity is greater than half the maximum intensity of the intensity peak. With solid-state lasers in the UV, the half-width can theoretically be less than one micrometer, but in MALDI applications it is typically between 20 and 200 micrometers. Even if laser pulse repetition rates of several hundred kilohertz are possible in principle with solid-state lasers, most current MALDI applications operate with a repetition rate of up to 200 hertz. The energy fluctuations from laser pulse to laser pulse are typically smaller in the case of solid-state lasers than with nitrogen lasers.
According to the prior art, the attempt is often made to achieve a spatially homogeneous intensity distribution on the sample in order to even out the inhomogeneities of the prepared MALDI sample, which occur, for example, in the case of non-uniform embedding of the analyte molecules in the matrix. In order to obtain a homogeneous intensity distribution on the sample with a Gaussian beam profile of a solid-state laser, the beam profile can be spatially homogenized by propagation in a fiber, and then imaged onto the sample. To facilitate this, the laser beam is coupled into a fiber in which a large number of transverse fiber modes with differing radial intensity distributions can propagate (multimode fibers). The propagation of the coupled laser beam in the multimode fiber means that energy is transferred out of the Gaussian beam mode and into a large number of transverse fiber modes which are superimposed at the output of the fiber. If the temporal coherence of the laser radiation used is sufficiently low, or the multimode fiber is sufficiently long, the intensity distribution at the end of the fiber is given by the sum of the intensity distributions of the individual transverse fiber modes. The large number of transverse fiber modes with differing radial intensity profiles thus results in a homogeneous intensity distribution at the end of the fiber. If the end of the multimode fiber is now imaged, a flat-top intensity distribution is also obtained on the sample. This method of homogenizing the beam profile is also used with the nitrogen laser to minimize the inherent inhomogeneities in the beam profile.
The quality of a mass spectrometric analysis is generally determined by the following parameters: mass accuracy, mass resolution, detection power, quantitative reproducibility and signal-to-noise ratio. The quality of a mass spectrometric analysis increases if at least one parameter is improved and the other parameters do not deteriorate as a result. The mass accuracy includes both a systematic deviation of the measured average ion mass from the true ion mass (mass trueness, or rather the deviation from mass trueness) and the statistical variance of the individual measured values around the mean of the ion mass (mass precision). The mass resolution determines which ion masses in the mass spectrometric analysis can still be distinguished. In practice, however, it is not only the quality but also the robustness of the mass spectrometric analysis that is important. A mass spectrometric analysis is robust if its quality changes little when the measuring parameters, for example the energy of the laser pulses or the preparation conditions of the MALDI sample, are
The ion signal of a mass spectrometer with MALDI is proportional to the ionization efficiency, to the desorbed sample volume and to the concentration of the analyte molecules in the sample. The ionization efficiency is given by the number of analyte ions, which can be evaluated, divided by the number of analyte molecules in the desorbed sample volume, i.e., the percentage of analyte molecules from the sample volume ablated by the laser irradiation which are available as ions for a mass spectrometric analysis. If analyte molecules are already present in the matrix as ions before the desorption process, the number of analyte molecules is increased by the number of analyte ions being already ionized. Since the desorbed sample volume can be relatively easily increased by the irradiated sample area and by the fluence, the ionization efficiency represents an important parameter for the optimization of the MALDI process. A high ionization efficiency permits a high detection power because a maximum ion signal at low concentration (or at low sample consumption) is achieved. With a typical degree of ionization of only 10−4 it is possible to considerably improve the MALDI process. The definition of the ionization efficiency of the MALDI process also takes into account the losses which arise as a result of a fragmentation of analyte molecules during the transfer into the gaseous phase, and therefore reduce the number of analyte ions which can be evaluated.
For mass spectrometric analysis of the analyte ions generated in the MALDI process, conventional sector field mass spectrometers and quadrupole mass spectrometers are suitable in principle, as are quadrupole ion trap mass spectrometers and ion cyclotron resonance mass spectrometers. However, particularly suitable are time-of-flight mass spectrometers with axial injection, which require a pulsed current of ions to measure the time of flight (TOF). In this case, the starting point for the time of flight measurement is dictated by the ionizing laser pulse. The MALDI process was originally developed for use in a vacuum. In more recent developments, matrix-assisted laser desorption/ionization is also used at atmospheric pressure (AP MALDI) or intermediate pressure. Here, the ions are generated with a repetition rate of up to 2 kilohertz and fed, with the help of an ion guide, to a with orthogonal injection (OTOF "orthogonal time of flight"), a quadrupole ion trap mass spectrometer or an ion cyclotron resonance mass spectrometer. In an OTOF mass spectrometer, the ions generated in the MALDI process can be fragmented and stored before the measurement of the time of flight is started by an electronic pulsed injection.
With specific analytical methods, the intensity on the sample is increased to such a degree that the ions generated have enough intrinsic energy to dissociate. Depending on the time between the generation of the ions and their dissociation, this is termed a decay within the ion source (ISD or "in-source decay") or outside the ion source (PSD or "post-source decay").
Moreover, there are also methods of imaging mass spectrometry analysis (IMS) in which the MALDI process is used to generate the ions. With IMS, a thin section of tissue obtained, for example, from a human organ, using a microtome, is prepared with a matrix substance, and mass spectrometrically analyzed with spatial resolution. The spatial resolution of the mass spectrometric analysis can be done either by scanning individual small spots of the tissue section or by stigmatic imaging of the ions generated. With the scanning method, the pulsed laser beam is focused onto a small diameter on the sample, and a mass spectrum is measured for each individual pixel. A one- or two-dimensional frequency distribution is produced for individual proteins from the large number of individual spatially resolved mass spectra. With stigmatic imaging, an area of up to 200 by 200 micrometers is irradiated homogeneously with a laser pulse. The ions generated in this way are imaged pixel by pixel onto a spatially resolving detector by an ion optic. Until now it has only been possible to scan the frequency distribution of one ion mass with a single laser pulse because spatially resolving ion detectors that operate fast enough are not available. The measured ion mass can be varied from laser pulse to laser pulse, however.

Laser system for the ionization of a sample by matrix-assisted laser desorption in mass spectrometric analysis


An energy saving type feeder voltage compensation apparatus improved in availability at low temperatures, wherein when a secondary battery is lower in temperature than a predetermined value, an output voltage output to a feeder side is made equal to or higher than a no-load output voltage of a substation connected in parallel. Power is supplied to a power running rolling stock preferentially from the secondary battery. The heating value of the secondary battery is increased and the battery temperature is raised by this discharging, whereby internal resistance of the secondary battery is lowered, and the charging and discharging loss is suppressed, and the efficiency and availability of the energy saving type feeder voltage compensation apparatus as a whole are improved.

The present invention relates to an energy storage type feeder voltage compensation apparatus and a method of controlling feeder voltage in which a secondary battery is connected to a feeder of an electric railroad via a power converter to absorb surplus power on the feeder and supply power from a secondary battery in response to power demand from power running rolling stocks.
In recent years, in a feeder system for supplying power from a substation to an electric rolling stock, the electric rolling stock utilizes regenerative brake with the object of power saving. This regenerative brake converts kinetic energy of the electric rolling stock to electric energy by using an inverter mounted on the electric rolling stock, regenerates the electric energy to the feeder, and decelerates the electric rolling stock. The electric energy generated by the regenerative brake is consumed as power running energy of other electric rolling stocks. As a result, energy saving in the feeder system can be attained.
If higher electric energy than needed in the neighborhood of the regenerative rolling stock, i.e., surplus regenerative power is generated, however, the voltage at a receiving point on the regenerative rolling stock rises. In the rolling stock, therefore, the brake must be altered from the regenerative brake to mechanical brake for the purpose of overvoltage protection. As a result, not only the electric rolling stock becomes uncomfortable to ride in, but also the power saving in the feeder system is aggravated.
To solve this problem, a method of storing surplus power in an energy storage apparatus and discharging the stored power as energy at the time of power running of the rolling stock is disclosed in JP-A-11-91415.
A control method for a feeder voltage compensation apparatus including an energy storage apparatus and a power converter is disclosed in MEIDEN REVIEW, Vol. 287, 2002, No. 6, pp. 4-7. An electric double layer capacitor is used as the energy storage apparatus. If the feeder voltage exceeds an upper limit value, the energy storage apparatus is charged. If the feeder voltage becomes lower than a lower limit value, the energy storage apparatus is discharged to suppress the variation in feeder voltage. In addition, when the feeder voltage is in a predetermined range, charging and discharging are conducted between the feeder and the energy saving apparatus so as to make the voltage on the electric double layer capacitor constant. As a result, regenerative power is used effectively, and the charging rate of the power saving apparatus is controlled. In addition, stable operation of the device is ensured.
If a secondary battery is used in the power saving apparatus using the technique disclosed in Meiden Periodical Report, Vol. 287, 2002, No. 6, pp. 4-7, however, the internal resistance value of the secondary battery becomes large at low temperatures, and chargeable and dischargeable power is restricted, resulting in a problem of a lowered availability of the device.

Energy storage type feeder voltage compensation apparatus and method of controlling feeder voltage


The invention provides a golf ball comprising a core and a cover of one or more layers, characterized in that the golf ball has an outer diameter of 43.0–45.0 mm and an initial velocity of at least 77.5 m/s measured by the USGA rotary drum initial velocity instrument approved by R&A. The golf ball minimizes the difference in travel distance with a driver (W#1) between high-head speed golfers and low-head speed golfers.

This invention relates to a golf ball which reduces the difference in travel distance with a driver (W#1) between high-head speed golfers and low-head speed golfers, as compared with prior art golf balls.
A number of golf balls having a larger outer diameter were proposed in the prior art. Such golf balls are known, for example, from U.S. Pat. No. 5,209,485, U.S. Pat. No. 5,273,287, U.S. Pat. No. 5,470,075, U.S. Pat. No. 5,482,286, U.S. Pat. No. 5,503,397, U.S. Pat. No. 5,507,493, U.S. Pat. No. 5,569,100, U.S. Pat. No. 5,588,924, U.S. Pat. No. 5,738,597, U.S. Pat. No. 5,833,554, U.S. Pat. No. 5,971,871, U.S. Pat. No. 6,102,816, U.S. Pat. No. 5,433,447, U.S. Pat. No. 6,315,683, U.S. Pat. No. 5,601,503, U.S. Pat. No. 5,609,532, U.S. Pat. No. 5,720,675, etc.
However, increasing the outer diameter of balls invites a loss of travel distance. This tendency becomes prominent especially in a high head speed region, failing to satisfy those golfers with an ability in that high head speed region, with respect to travel distance.
Also, simply increasing the initial velocity of golf balls permits not only low-head speed (HS) golfers, but also high-head speed golfers to get a gain in travel distance. For example, balls tailored to an initial velocity of at least 77.7 m/s are described in U.S. Pat. No. 5,846,141, U.S. Pat. No. 6,626,771, U.S. Pat. No. 6,672,976, etc.
However, since these golf balls place a focus on the improvement in dimples formed on the ball surface, their improvements in ball outer diameter and structure are insufficient. When two high and low-head speed golfers play with the same golf balls, there arises a significant difference in travel distance. This becomes a practical disadvantage to the low head speed golfer, achieving no compensation for the handicap. Therefore, if the difference in travel distance between high and low-head speed golfers is reduced to lessen the handicap difference between them, the ball becomes of greater value in use by high and low-head speed golfers.


An aniline monomer having a phosphonic acid of general formula (4) is polymerized to produce a polyaniline. In the formula, R1 is NH2 or NH3X, and X is a halogen. R2 are each independently a phosphonic acid or a salt thereof. R3 are each independently selected from the group consisting of a halogen atom, alkyl group having 1-15 carbon atoms, aralkyl group having 7-34 carbon atoms, alkoxy group having 1-15 carbon atoms, alkylthio group having 1-15 carbon atoms, alkylamino group having 1-15 carbon atoms, carboxyl group, carboxylic acid alkyl ester group wherein the alkyl group has 1-15 carbon atoms, nitro group, and cyano group. m is an integer of 1-4, n is an integer of 0-3, and the sum of m and n is 1-4. However, none of R2 and R3 is present at the para position relative to R1.

Electrically conductive polymers represented by polythiophene, polypyrrole, polyaniline and the like are a group of compounds that have been actively developed in the field of "organic electronics" recently. In the subject field, substances having conductivity in the range from about 10−2 to about 10−6 S/m are generally used as antistatic agents, static removing agent and the like.
Among such electrically conductive polymers, particularly, a polyaniline is obtainable from inexpensive raw materials, and a polyaniline is one of the first electrically conductive polymers that are in practical use. Thus, polyaniline that does not have any substituents is used as electrically conductive material. In order to cause polyaniline that does not have any substituents to achieve conductivity, however, it is necessary to perform doping (also referred to as dope) treatment with an acceptor or a donor with proton, iodine or the like, and such polyaniline itself that does not have any substituents does not have conductivity. Moreover, polyaniline that does not have any substituents is generally insoluble in solvents, and it is thus difficult to be shaped into a desired form, thus having a problem of poor workability.
In order to solve such a problem of a polyaniline that does not have any substituents, polyanilines, which are obtained by introducing a long chain alkyl group, ketone group, ether group or the like into polyaniline, with improved solubility against organic solvents have been reported. In the present specification, unless otherwise stated, the term "polyaniline" refers to both those that do not have any substituents and those that have substituents.
In addition, with regard to productivity, cost and the like in producing and shape processing of polyaniline, it is desirable for polyaniline to be water soluble. Thus, polyanilines with given water solubility have been recently developed by introducing an acidic substituent having proton into polyaniline. Furthermore, with regard to such polyaniline to which an acidic substituent is introduced, when the acidic substituent is introduced, the proton of the acidic substituent is doped. Thus, there is an advantage of obtaining conductivity without the need of performing a doping process separately (which is referred to as self-dope or self-doping). With regard to the acidic substituent herein, those in which a sulfo group (—S(O)2OH) or phosphonic acid group (—P(O)(OH)2) is used are known. Some of them are developed or expected in the use for prevention of static charge due to their conductivity.
As to polyaniline to which a sulfo group is introduced, "those obtained by sulfonating unsubstituted polyaniline with fuming sulfuric acid or chlorosulfuric acid" (Patent Document 1) and "those obtained by polymerizing aniline-sulfonic acids" (Patent Document 2) are known. In the method of performing sulfonation as described in Patent Document 1, a greatly excess amount of sulfonation agents are used for polyaniline to perform sulfonation, and a large amount of acidic waste is produced, resulting in a problem of difficulty in the disposal thereof. The method using aniline-sulfonic acids as described in Patent Document 2 has a problem of high product cost due to the high price of the raw material.
With regard to polyaniline having a phosphonic acid group, a method of polymerizing o-aminobenzylphosphonic acid to obtain poly(o-aminobenzylphosphonic acid) has been reported (Non-Patent Document 1). With this method, however, multiple stages of reaction are required to obtain a raw material that is used for polymerization. Specifically, a step of allowing o-bromomethyl-nitrobenzene (Br is present in Compound 1 in Scheme 1 on page 8518 of Non-Patent Document 1, and thus the description of "o-methylnitrobenzene 1" on page 8518, left column, 9th line from the bottom is a typographical error) to react with triethyl phosphite to obtain diethyl o-nitrobenzylphosphonate 2 (hereinafter, referred to as step 1); a step of reducing the diethyl o-nitrobenzylphosphonate 2 with cyclohexane to obtain diethyl o-aminobenzylphosphonate 3 (hereinafter, referred to as step 2); and a step of hydrolyzing the diethyl o-aminobenzylphosphonate 3 with concentrated hydrochloric acid to obtain o-aminobenzylphosphonic acid 4 (hereinafter, referred to as step 3) are performed to obtain a monomer that is used for polymerization. Furthermore, purification must be performed at each reaction, and thus there are many industrial problems to be solved from the viewpoint of productivity. In detail, it is necessary to perform reaction with 3 steps to obtain a raw material prior to polymerization, and including the polymerization, it is necessary to perform reaction of 4 steps. In Non-Patent Document 1, the yield and purification method of the respective steps are as follows: step 1: 64% (purification using column chromatography), step 2: 71% (purification using ion exchange), step 3: 65% (purification using recrystallization), and step 4 (polymerization): 30%.
As described above, various studies have been conducted for polyaniline; and with regard to the technique of allowing polyaniline to have an acidic substituent, sulfo groups are mainly studied as the acidic substituent. With regard to the technique of introducing a phosphonic acid group, those skilled in the art do not pay a lot of attention on it because the technique has some disadvantages such as complication of the producing steps, and no active studies have been conducted therefor. In particular, no studies have been conducted for the use of aniline monomers having a structure in which a phosphonic acid group is directly bound to a benzene ring.
Now, with regard to the mechanism of a polymerization reaction of aniline monomers as well as the structure of polyaniline, and the mechanism of expressing the conductivity, while there are some parts that have not been completely clarified, a variety of studies have been conducted and a variety of findings have been discovered.
For example, Yano et al., BUNSEKI KAGAKU Vol. 46, No. 5, pp. 343-349 (Non-Patent Document 2), Japanese Laid-Open Publication No. 2003-192786 (Patent Document 3), J. Stejekal et al., Progress in Polymer Science 35 (2010) 1420-1481 (Non-Patent Document 3) and Mukai et al., Keio University Hiyoshi Kiyou, Shizen Kagaku (The Hiyoshi review of the natural science), No. 50 (2011.9), p. 61-75 (Non-Patent Document 4), describe the mechanism of a polymerization reaction of aniline monomers.
Furthermore, Hino et al., Yamagata University Kiyou (engineering), Vol. 29, No. 2, February, Heisei-19 (Non-Patent Document 5) describes the mechanism of an oxidative polymerization of polyaniline and the structure of polyaniline obtained by an oxidative polymerization. Specifically, it is described that: a structure with conductivity referred to as an emeraldine salt is formed by an oxidative polymerization, and when the emeraldine salt is treated in an alkaline solution, an insulating structure referred to as emeraldine base is formed; when the emeraldine base is reduced, a structure referred to as leucoemeraldine is formed; and when the emeraldine base is oxidized, a structure referred to as pernigraniline is formed.
It is a well-known fact that polyaniline takes such four types of structures; and for example, Japanese Laid-Open Publication No. 2004-99673 (Patent Document 4), Japanese Laid-Open Publication No. 2008-33203 (Patent Document 5), and Japanese National Phase PCT Laid-open Publication No. 2011-501379 (Patent Document 6) describe the above-mentioned four types of structures.
It should be noted that while reactions in which phosphite is caused to bind with a benzene ring in the presence of a catalyst such as a palladium compound are publicly known (Non-Patent Documents 6 to 10), such reactions are solely studied for the purpose of developing a method for introducing a substituent into a benzene ring, and these reactions have not been known to be used for synthesis of polymers.

Method for producing polyaniline having self-doping function and antistatic agent containing polyaniline produced thereby


A musical tone generating apparatus is provided that generates a musical tone of a selected one of tone colors that is defined by a combination of a first kind of number and a second kind of number. An operating element used for setting a tone color and having an incrementing function and a decrementing function is operated to set at least the second kind of number by using at least one of the incrementing function and decrementing function. A memory device stores a list in which the tone colors to be selected are listed, the list having a first axis having a plurality of locations to which a plurality of first kind of numbers are respectively assigned, and a second axis having a plurality of locations to which a plurality of second kind of numbers are respectively assigned, each of the first kind of numbers having a basic tone color assigned thereto, each of the second kind of numbers having an extended tone color that is a variation of the basic tone color of a corresponding one of the first kind of numbers. Each time the operating element is operated, one of the second kind of numbers that is assigned to a currently selected tone color is changed to a number of the second kind assigned to a tone color that is different from the currently selected tone color and is present next to the currently selected tone color in the list.

1. Field of the Invention
The present invention relates to a musical tone generating apparatus, a musical tone generating method and a storage medium, wherein a first kind of number and a second kind of number are used to select a tone color of musical tones to be generated, from a tone color table.
2. Prior Art
A sound source module is known as a musical tone generating apparatus adapted for generating musical tones in accordance with MIDI events entered through a keyboard, sequencer, or the like.
In an example of the sound source module, the tone color of a musical tone to be generated may be set by a bank number and a program change number, where the bank number is taken along the abscissa, and the program change number is taken along the ordinate, as shown in FIG. 3. For instance, the sound source module uses a tone color list or table that has 128 locations in rows to which bank numbers "0" through "127" are respectively assigned, and 128 locations in columns to which program change numbers "0" through "127" are respectively assigned. A particular tone color at the address (n, m) may be selected by setting the bank number to "n", and setting the program change number to "m".
One example of the above-described tone color list is shown in FIGS. 4, 5 and 6. It is to be noted that only two musical instrument groups of basic tones, namely, those of Piano and Bass, are shown in FIGS. 4-6, and other fourteen musical instrument groups are not shown herein. While this tone color list contains 128 banks as numbered from "0" to "127", banks following the bank number "65" are omitted in FIG. 6.
In this tone color list, eight program change numbers are assigned to each musical instrument group, and eight basic tone colors are stored in each musical instrument group. These basic tone colors are stored in the column of bank number "0", and the total number of basic tone colors stored in the bank number "0" is 128, namely 128 kinds of basic tone colors are stored in the tone color list.
Each bank having the bank number "1" to "127" may store an extended tone color that is a variation of a corresponding basic color stored in the bank number "0". The extended tone colors, however, are not necessarily stored in all of the banks having the bank numbers "1" through "127".
For example, extended tone colors of basic tone color "SynBass2" stored at the location of the program change number "40" and bank number "0" in the Bass group, for example, include an extended tone color "MelloSB1" stored at bank number "6", an extended tone color "Seq Bass" stored at bank number "12", an extended tone color "ClkSynBa" stored at bank number "18", an extended tone color "SynBa2DK" stored at bank number "19", and others. When the user selects a bank in which no extended tone color is named, musical tones having a corresponding basic tone color are generated.
When the sound source module having the above-described tone color list is used to generate musical tones, the user sets the bank number and program change number to appropriate values by means of a switch device, so that musical tones having a desired tone color are generated. This switch device consists of an increment switch and a decrement switch. In setting the bank number, the bank number is increased by 1 if the increment switch is operated by the user, and the bank number is decreased by 1 if the decrement switch is operated.
One example of setting of the bank number will be illustrated with respect to tone color "SynBass2" stored at the address of bank number "0" and program change number "40" (which will be referred to as "address (0, 40)"). If the increment switch is operated by the user while the tone color at the address (0, 40) is selected, this address is changed to address (1, 40) at which the basic tone color "Synbass2" is selected. If the increment switch is operated again, the current address is changed to address (2, 40) at which the basic tone color "Synbass2" is selected. If the increment switch is then serially operated, the current address is changed to address (3, 40) where the basic tone color "SynBass2" is selected, address (4, 40) where the basic tone color "SynBass2" is selected, address (5, 40) where the basic tone color "SynBass2" is selected, and then to the address (6, 40) where extended tone color "MelloSB1" is selected. Thus, the increment switch is operated six times so that the first extended tone color "MelloSB1" is selected. Since the second extended tone color "Seq Bass" is stored at address (12, 40) that is 6 banks ahead of the current address (6, 40), the same switch needs to be operated additional six times so as to select this extended tone color "Seq Bass".
Thus, the known sound source module has a problem that a desired tone color cannot be efficiently selected.

Musical tone generating apparatus, musical tone generating method and storage medium


There is disclosed a fluid treatment device comprising a housing for receiving a flow of fluid. The housing comprises a fluid inlet, a fluid outlet, a closed fluid treatment zone disposed between the fluid inlet and the fluid outlet. Disposed in the housing is at least one elongate radiation source assembly having a longitudinal axis disposed in the fluid treatment zone substantially parallel to a direction of the flow of fluid through the housing. The radiation source assembly comprises an elongate radiation source disposed in a protective sleeve to define a substantially annular passageway. The protective sleeve has opposed open ends configured to permit heat to exit the passageway and the housing through at least one of the opposed open ends of the sleeve.

1. Field of the Invention
The present invention relates to a fluid treatment device. More particularly, in its preferred embodiment, the present invention relates to an ultraviolet radiation water treatment device.
2. Description of the Prior Art
Fluid treatment devices and systems are known. For example, U.S. Pat. Nos. 4,482,809, 4,872,980, 5,006,244 and 5,590,390 (all assigned to the assignee of the present invention) all describe gravity fed fluid treatment systems which employ ultraviolet (UV) radiation to inactivate microorganisms present in the fluid.
The devices and systems described in the '809, '980 and '244 patents generally include several UV lamps each of which are mounted within sleeves extending between two support arms of the frames. The frames are immersed into the fluid to be treated which is then irradiated as required. The amount of radiation to which the fluid is exposed is determined by the proximity of the fluid to the lamps. One or more UV sensors may be employed to monitor the UV output of the lamps and the fluid level is typically controlled, to some extent, downstream of the treatment device by means of level gates or the like. Since, at higher flow rates, accurate fluid level control is difficult to achieve in gravity fed systems, fluctuations in fluid level are inevitable. Such fluctuations could lead to non-uniform irradiation in the treated fluid.
So-called closed fluid treatment devices are known—see, for example, U.S. Pat. No. 5,504,335 (assigned to the assignee of the present invention). The '335 patent teaches a closed fluid treatment device comprising a housing for receiving a flow of fluid. The housing comprises a fluid inlet, a fluid outlet, a fluid treatment zone disposed between the fluid inlet and the fluid outlet, and at least one radiation source module disposed in the fluid treatment zone. The fluid inlet, the fluid outlet and the fluid treatment zone are in a collinear relationship with respect to one another. The at least one radiation source module comprises a radiation source sealably connected to a leg which is sealably mounted to the housing. The radiation source is disposed substantially parallel to the flow of fluid. The radiation source module is removable through an aperture provided in the housing intermediate to fluid inlet and the fluid outlet thereby obviating the need to physically remove the device for service of the radiation source. A disadvantage with this kind of closed fluid treatment device is that the seal between the radiation source module and the housing must be broken each time the former is to be serviced. This confers additional cost and complexity to the servicing needs of the device.
U.S. Pat. No. 6,500,346 (assigned to the assignee of the present invention) teaches a fluid treatment device, particularly useful for ultraviolet radiation treatment of fluids such as water. The device comprises a housing for receiving a flow of fluid. The housing has a fluid inlet, a fluid outlet, a fluid treatment zone disposed between the fluid inlet and the fluid outlet and at least one radiation source having a longitudinal axis disposed in the fluid treatment zone substantially transverse to a direction of the flow of fluid through the housing. The fluid inlet, the fluid outlet and the fluid treatment zone are arranged substantially collinearly with respect to one another. The fluid inlet has a first opening having: (i) a cross-sectional area less than a cross-sectional area of the fluid treatment zone, and (ii) a largest diameter substantially parallel to the longitudinal axis of the at least one radiation source assembly.
Many of the above mentioned fluid treatment systems have achieved significant commercial success in the treatment of municipal waste water and/or municipal drinking water.
In certain cases, it would be desirable to have a fluid treatment system for use in treating relatively low volumes of water—e.g., for domestic use, for use in an office environment, etc.
In this regard, reference may be made to:
U.S. Pat. No. 4,179,616,
U.S. Pat. No. 5,471,063 (assigned to the assignee of the present invention),
U.S. Pat. NO. 6,139,726,
U.S. Pat. No. 6,679,068, and
U.S. Pat. No. 6,832,844.
The '063 patent teaches fluid disinfection unit comprising a fluid treatment housing, an electrical supply module and electrical connection means connecting the fluid treatment housing and the electrical supply module. The fluid treatment housing comprises a fluid inlet and a fluid outlet in communication with a reaction chamber, an ultraviolet radiation lamp disposed in the reaction chamber and having a first electrical connector at a first end thereof and a second end thereof being closed. The second end of the ultraviolet radiation lamp is received and held in place by tapered, helical spring. The electrical supply module comprises ballast and which may be removably connected to the ultraviolet radiation lamp and the electrical supply module.
The device taught by the '063 patent has been commercially available from Trojan Technologies Inc. under the tradename Trojan UVMax™ and has achieved commercially success. Notwithstanding this, there is room for improvement.
One of the problems with devices such as those taught by the '063 patent is fluctuation in the environment surrounding the radiation source. This occurs primarily due to the fact that the temperature of the fluid (typically water) surrounding lamp is variable. The variability in temperature can occur to variability of the temperature of the fluid entering the fluid treatment system. Further, the variability of the temperature can occur due to fluid resting in the system when the system is in a non-flowing condition. Since the radiation source is constantly powered, fluid resting in the system will become relatively warmer (i.e., as compared to when fluid is passing through the system) thereby increasing the temperature of the environment around the radiation source.
In recent years, improvements in radiation source (e.g., lamp) technology have developed to the point that radiation sources are designed to operate at an optimum temperature—e.g., for achieving specified disinfection levels and the like. It is important to optimally control the temperature surrounding the radiation source to maintain optimum operation of the radiation source.
Further, over the years, the art has transitioned toward the use of protective sleeves for radiation lamps, wherein the protective sleeves an open end and a closed end thereby facilitating sealing of the radiation lamp—this is particularly important in water submersible systems.
Accordingly, it would be highly desirable to have a fluid treatment system in which the temperature of the environment surrounding the radiation source is relatively constant. More particularly, it would be highly desirable to have a fluid treatment system in which the occurrence of resting fluid described above and fluid temperature fluctuations had little or no effect on the operating temperature of the radiation source.


An electroshock device with a more effective physiological impact uses Shaped Pulse technology and integrated STUN GUN/EMD technology to produce high-voltage pulse transformers, and is distinguished by the considerable visual effect of its demonstration release of electric discharge. In one embodiment, the device employs parameters of electric discharges having frequencies of 100-200 Hz with pulse energy of at least 0.1 J and a pulse duration up to 1000 milliseconds, which allows one to achieve the goal of stopping and capturing the target. In other embodiments, a series of impulses based on STUN GUN technology alternate with separate impulses based on EMD technology in a single, uninterrupted electric discharge by which the target-stopping and target-capturing mechanisms are attained.

There are widely known electroshock devices containing an autonomous electric power supply (storage cell or battery), a converter of the electric power supply's low-voltage direct current to direct current of 600-4000 volts, a storage capacitor and a circuit consisting of the sequentially engaged low-voltage coil of an output high-voltage pulse transformer and a switch for which, as a rule, a pneumatic or gas discharger is used with ignition voltage that is 15-50% less than the output voltage of the converter when empty, which are connected in parallel to the converter outlet. These devices have the following drawbacks:
1. A low performance index due to energy losses at the high-voltage output pulse transformer.
2. Insufficient duration and energy of the individual pulse for stopping a target, due to the insufficient induction coefficient of the known high-voltage pulse transformers in the requisite size for handheld devices, and the negligible performance index energy transmission from a large-capacity storage capacitor through a high-voltage pulse transformer to a target.
Contemporary notions on the physiological effectiveness of the impact of an electric shock impulse, corroborated by numerous experiments by a leading global manufacturer of a non-lethal electroshock weapon, Taser International, Inc. (USA), include two operative mechanisms of a physiologically effective electric impulse. The operative mechanism (technology) that was first studied and is used in an absolute majority of electroshock devices, called the STUN GUN, induces pain shock in the receptor nerve endings as a current of electric impulses of short duration (10-40 milliseconds) and negligible energy (0.05-0.1 J), with a frequency of about 100-200 Hz passes through the surface layers of the tissues and muscles. The effect of these impulses is to induce strong sensations of paid, which cannot stop an attacker having a substantial pain threshold. However, such impulses have considerable aftereffects, from several seconds to several minutes, after the current ceases, expressed in numbness, trembling, muscle contractions around the area where voltage was applied, and general unpleasant sensations that prevent the attacker from taking effective action during the indicated time period following the impact of the electroshock device. This condition that follows the use of the electroshock device against an attacker makes it relatively easy to capture (e.g., handcuff) him.
The second operative mechanism (technology) that uses an electric impulse, called the EMD [Electro-Muscular Disruption] effect, overwhelms the skeletal musculature due to the penetration of high-energy current (no less than 1.76 J) at a frequency of 10-30 Hz into the deep muscle layers. The passage of such impulses induces negligible pain sensations since the current travels below the receptor nerve endings, but at the same time the skeletal muscles are completely overwhelmed and cannot be directed at will. These impulses can stop an attacker with any pain threshold, leading to the attacker's falling down, virtually regardless of where the current is applied (trunk or extremity). However, these impulses have virtually no aftereffects (that is, after the current ceases to run through the target, no subsequent unpleasant sensations are observed that might reduce the target's level of activity), which precludes capturing the attacker after the current's effect ceases.
To the present day, attempts to combine the effects of the STUN GUN and EMD technologies in a single electrical impulse in standard high-voltage pulse transformers with a duration of 30-40 milliseconds, uniting the operative mechanisms of both impulses, have yielded no success, due to the varied depth at which the skeletal musculature is located in the human body (need for high energy in an individual impulse). However, with high energy delivered in individual impulses, the current from which spreads deep into the conducting body following Kirchgoff's rule, no pain shock is brought about in the receptor nerve endings located on the body's surface. Research conducted in the USA and Russia has shown that increasing the duration of the impulse to over 120-150 milliseconds makes it possible to substantially reduce (virtually by an order of magnitude) its energy in order to attain the operative mechanism of the EMD. However at the present time, the impulses in the widely-used high-voltage pulse transformers that meet other electrical performance requirements, including the chief performance property, "spark gap through air", do not exceed 20-40 milliseconds in duration.
At present, the electroshock devices of the leading worldwide firm, Taser International, Inc., use the EMD technology in applying the Shaped Pulse technology (that is, preliminarily ionizing the discharge gap with a low-energy initial discharge in order for a strong impulse from the storage capacitor to pass along an ionized air channel). In the Shaped Pulse technology, an increase in the KPD of a discharge from storage capacitor(s) is attained by arranging for it to be discharged without being directly transformed into a discharge gap between the target and the shock electrodes (tactical electrodes), ionized by the preliminary, low-power discharge from the high-voltage pulse transformer.
An electroshock device that uses the EMD/Shaped Pulse technology is known under US Patent Publication No. 2004/156,163. It contains an autonomous electrical power supply; a converter of the electric power supply's direct-current low voltage to a current of about 2,000 volts, which is removable from the coil 3-4 of the converter transformer T1; a storage capacitor C1 that is connected in parallel through a diode D1 to the converter's outlet; a circuit made of a sequentially connected low-voltage coil of the high-voltage outgoing pulse transformer T2 (see FIGS. 23 and 24 of the patent description); and a switch GAP1, for which a gas discharger is used, the ignition voltage of which is 15-50% lower than the outgoing voltage of the converter when empty. The high-voltage coil of the impulse transformer has two coils; capacitors C2 and C3 and gas dischargers GAP2 and GAP3 are connected to each coil. Capacitors C2 and C3 are charged from separate coils of converter transformer T1 through diodes D2 and D3. After capacitor C1 is discharged through the primary coil of transformer T2, voltage in the phased secondary coils of transformer T2 turns out to be enclosed in the Rn-E1-GAP2-C2-C3-GAP3-E2 loop. At the same time, a disruption occurs among the device's discharge (tactical) electrodes. After the E1-Rn-E2 air gap is ruptured by a high-voltage discharge, its resistance goes down as a result of the ionization of the air, due to which the charged capacitors C2 and C3 begin discharging through the above-indicated contour, providing the basic power for the impulse that strikes the target. This device, and the one in FIG. 25 of the patent (the basic operating principle of which does not differ from the one described here) have the following drawbacks:
1. The low frequency of the strike impulses (no more than 25 Hz) with substantial pulse energy, approaching that of the EMD technology. Such a device facilitates performance of the target-stopping function, but when it is switched off it fails to fulfill the function of capturing the target, since the operative mechanism of the STUN GUN is not realized when discharge frequency is very low while discharge energy is substantial.
2. The complexity of executing the T1 and T2 transformers due to the large number of coils and the complications involved in isolating them to prevent abnormal disruptions between the turns of the coil.
Another electroshock device that uses Shaped Pulse technology is known under Russian patent No. 2108526 (see diagram in patent description). It contains an electric power supply, a direct-current converter 3 to convert the power supply's low voltage into voltage current in order to charge the storage capacitor C4, which is sequentially connected to the low-voltage coil of the high-voltage outgoing pulse transformer and discharger. The supplemental capacitor C5 is connected in parallel to capacitor C4 through the diode D6 from voltage converter 3. The high-voltage impulse transformer is made in the form of an autotransformer, the central terminal of which is connected to a common point of both capacitors and to the terminal of converter 3. One tactical (target-impacting) electrode is connected to the end of the autotransformer's high-voltage coil, while the other is connected to the point where the supplemental capacitor and diode connect. When the device operates, the converter simultaneously charges capacitors C4 and C5, the discharger 7 (having a low breakdown voltage of about 1000-2000 volts) breaks and capacitor C4 discharges into the low-voltage portion of the autotransformer's coil. Capacitor C5 is prevented by diode D6 from discharging into the low-voltage coil. A high-voltage pulse, induced in the high-voltage portion of the autotransformer coil in the event the target's resistance is far removed from tactical electrodes 12 and 13, breaks discharger 11 (usually called the "cutting electrodes" of the electric shocker). The spark travels through the air between the cutting electrodes without causing a discharge of capacitor C5. If the target resistance is located at a distance from tactical electrodes 12 and 13 that is less than the spark gap between the cutting electrodes, the discharge to the target occurs between tactical electrodes 12 and 13 and the reduced resistance of the ionized discharge channel causes capacitor C5 to discharge into that channel, which increases the force of the discharge. For the purpose of eliminating any residual direct current from capacitor C5 in the event the device acts through the cutting electrodes (for example, in a demonstration), the safety discharger 14 engages in sequence with the high-voltage circuit, at a breakdown voltage greater than that of the charged capacitor C5. This device has the following drawbacks:
1. The chief requirement in using electroshock devices is the capability of releasing a demonstration discharge in front of an aggressive attacker, upon which, as practice has shown, the visibly powerful discharge of the electroshock gun (i.e. color, noise) is in most cases sufficient to psychologically deter an attack.
2. The chief requirement in the commercial use of electroshock devices (basic sales principle) is also the visual appearance of the discharge, i.e., its color and the noise it produces, on the basis of which the buyer chooses in favor of one or another model of electroshock gun. Electroshock guns, even those that are truly more effective in the physiological effect of their discharge, always lose out to electroshock guns whose discharge is less effective physiologically but more visually effective. A demonstration discharge by the above-described electroshock gun, produced through the cutting electrodes (discharger 11), has a poor visual effect, since it is arranged without a discharge by capacitor C5, which contributes considerable noise to the visual appearance of the discharge and visibly enlarges its spark. Thus the commercialization from sales of the above-described electroshock device to develop the market and, accordingly, create additional jobs does not exceed the commercialization of all other models of electroshock devices under production. At present, no electroshock devices are being produced under the above-cited patent.
3. The production of high-voltage pulse transformers, a crucial component of an electroshock device for the quality of manufacture required, with wire of various diameters for the parts of the common coil (as required under the above-cited patent) is technologically complex and fails to attract the attention of manufacturers, as shown by the complete absence of autotransformer electroshock devices on the market.


A nano-liquid crystal on silicon (nano-LCoS) chip having carbon nanotube (CNT) pillars that are grown on a glass substrate thereof. As the heights of the CNT pillars are uniform, the CNT pillars can function as spacers providing a uniform cell gap between the glass substrate and a silicon chip of the nano-LCoS chip. Also, being excellent electrical conductors, CNT pillars can form a part of the electrical connection between an outside voltage source and the indium tin oxide (ITO) layer formed on the glass substrate. The nano-LCoS chip includes nano-LCoS alignment keys that are formed in the silicon chip and connected to the CNT pillars. By applying the same voltage to the ITO layer and keys, a portion of the liquid crystal activated by the keys become transparent fiduciary marks for optical alignment of nano-LCoS chips.

The present invention relates to micro-display devices, and more particularly to liquid crystal on silicon (LCoS) chip having carbon nanotube (CNT) pillars.
A micro-display device having LCoS structure (shortly, LCoS device) is an important component of various optical projection systems. LCoS devices, typically in the form of chips, are becoming increasingly prevalent in micro-display applications, such as big-screen TV, PC monitor, projector, etc. and may eventually replace cathode ray tubes (CRTs) in various visual display devices. (Hereinafter, term LCoS chip and LCoS device are used interchangeably.) A conventional LCoS chip has a liquid crystal positioned on a silicon substrate, where the light incident on the LCoS chip carries the information of images formed in the liquid crystal and is subsequently expanded by an optical system to display the images for human eyes. A conventional high-definition (HD) TV screen may have 1,920 and 1,080 scan lines in the horizontal and vertical directions, respectively.
One of the important parameters determining the image quality of an LCoS chip is the uniformity of the cell gap (sometimes referred to as the "cell spacing") in the LCoS chip. The cell gap is the space between the upper and lower substrates of the chip, with the liquid crystal being contained within the cell gap. For liquid crystal displays (LCDs), the upper and lower substrates are typically made of glass material. For LCoS chips, the upper substrate is typically made of glass, and the lower substrate is made of silicon, as illustrated in FIGS. 1A-1D.
FIG. 1A is an exploded perspective view of a conventional LCoS chip shown at 100, illustrating only few components for the purpose of simplicity. As depicted, the LCoS chip includes: an upper glass substrate 104; an indium tin oxide (ITO) layer 106; a lower silicon substrate 108; a ceramic substrate 102 for providing mechanical support for the silicon substrate 108; and an ITO connector 114, where the ITO connector 114 forms a part of the electrical connection from an outside voltage source to the ITO layer 106. Interposed between the upper 104 and lower substrates 108 is a rim seal 110 for containing a liquid crystal 112. The silicon substrate 108 includes electrical circuitry for forming images in the liquid crystal 112, where the incoming light 116a reflects from the silicon substrate 108 to become an outgoing light 116b carrying the image information. The rim seal 110 includes spacers 136 (FIG. 1B) that may provide uniformity of the cell gap and have a spherical or a cylindrical shape.
It is well known that a consistency in the thickness and/or uniformity of the liquid crystal 112 within the rim seal 110 must be achieved in order to obtain a high-quality optical image on the screen. In manufacturing the LCoS chip shown at 100, the typical practice is to spray the spacers 136 on a rim seal 110 prior to assembling or mating the glass substrate 104 (having the ITO layer 106 formed thereon) with the silicon semiconductor substrate 108. The term "mating" refers to the process of mounting the glass substrate 104 on top of the silicon substrate 108, applying a preset pressure and curing the rim seal 110. The uneven height defined by spacers 136, 156, and 176, as illustrated in FIGS. 1B-1D, results in non-uniformity of the cell gap, which in turn generates undesirable optical rings or color image shifts on the screen. FIGS. 1B-1D are cross sectional views of conventional LCoS chips, taken along the direction A-A (FIG. 1A), where the upper glass substrates 124, 144, and 164 are curved (convex or concave) or tilted with respect to the silicon substrates 128, 148, and 168, respectively, due to the non-uniformity of the spacer dimension.
As consumers can easily perceive the optical rings or color image shifts, the non-uniformity has been a challenging problem to overcome. To alleviate this problem, for example, many commercially available LCoS chips are fabricated without spacers. However, this process is not a guarantee for quality or yield because with larger size variations of silicon substrates or with thinner cell gaps, it is mechanically difficult to support constant spacing uniformity when mating the upper substrate with the lower substrate. In fact, this can become a serious issue if yield is significantly reduced due to the higher number of LCoS chips that will need to be discarded for having poor uniformity. Thus, there has been a strong need for a new approach to control the cell gap and provide a consistency in the uniformity of the liquid crystal.

Liquid crystal on silicon micro-display using carbon nanotube

Wuhan Splendid Optronics Technology Co., Ltd.


An apparatus includes a pressure vessel with a closure structure (14) including a part (62) consisting of a single, continuous body of homogeneous metal material. The part (62) has a plurality of fluid outlet openings (22), a fluid outlet conduit (88) communicating with the outlet openings (22), and a pocket (100) separate from the outlet conduit (88). The pocket (100) has a closed inner end (116) defined by a thin wall portion (120) of the part (62). An initiator (40) is received in the pocket (100), and is actuatable to rupture the thin wall portion (120) of the part (62). In a preferred embodiment, a retainer structure (102) holds the initiator (40) in the pocket (100). The retainer structure (102) and the part (62) have adjoining, unthreaded surfaces (160, 108) engaging each other in an interference fit which is tight enough to hold the retainer structure (102) and the initiator (40) in the pocket (100) when the initiator (40) is actuated.

An inflator for an inflatable vehicle occupant protection device, such as an air bag, may comprise a pressure vessel containing inflation fluid under pressure. Such an inflator is disclosed in U.S. Pat. No. 5,348,344. In the inflator disclosed in the '344 patent, the inflation fluid is an ingredient in a mixture of gases. The mixture of gases further includes a fuel gas which, when ignited, heats the inflation fluid.
The inflator has an igniter containing a small charge of pyrotechnic material. When the air bag is to be inflated, the igniter is actuated electrically. The pyrotechnic material is then ignited and produces combustion products which, in turn, ignite the fuel gas in the pressure vessel.
The fluid pressure inside the pressure vessel is increased by the heat generated upon combustion of the fuel gas. When the increasing fluid pressure reaches a predetermined elevated level, the pressure vessel is opened. The inflation fluid then flows outward from the pressure vessel and into the air bag to inflate the air bag.

Inflator for an inflatable vehicle occupant protection device


A byte code reader provides verification while optimizing and creating an internal SSA form to allow efficient machine code generation. Many functions are combined in one component honoring the difficult time constraints of just-in-time translation. This reader is engineered for retargeting and thus expedites the implementation of a JIT for any platform. The reader takes two single passes over the byte codes: a first pass that builds a flow graph using any set of rules for node creation, and maps definitions from the byte codes onto the flow graph nodes, and a second pass that translates whatever is in the byte codes into optimized machine code (or a traditional compiler intermediate form) with an embedded SSA graph. Global verification and global optimization are implemented while reading. Two data structures and a main program loop are provided. The data structures are used to allow the creation of a flow graph, and an exception handling (EH) graph.

Intermediate language (IL) code, such as MSIL (Microsoft Intermediate Language, produced by Microsoft Corporation, Redmond, Washington) or Java byte codes, is produced by a compiler at development time and then converted (e.g., JIT'ed or just-in-time translated) to machine code on a client machine. Conventionally, for each processor or platform supported, a different JIT compiler (referred to herein as a JIT) must be developed. Additionally, one of the typical steps performed by the client machine at run time is to verify the IL (or byte code stream) as part of the JIT process.
A JIT performs just-in-time translation of abstract byte codes to machine code under very tight time constraints that a normal compiler would not deal with. Conventionally, the prior art shows that a JIT will perform several passes (in different components) to produce optimized machine code that has been verified as safe for the target architecture. This invention improves on the prior art by performing both verification and optimizations in the JIT's reader, simultaneously, so that the resulting internal representation also contains an embedded form of analysis typically used for many traditional compiler optimizations. Additionally, this machine independent component can be easily re-targeted for many different processors. Thus, the invention provides a method to combine many functions in one pass which is a significant improvement to the prior art in an area (just-in-time translation) where time is critical.

Systems and methods to read, optimize, and verify byte codes for a multiplatform jit


1,3-Dihydroxybenzene derivatives of general formula (I) or (Ia) or physiologically tolerated, water-soluble salts thereof

1. Field of the Invention
The invention relates to novel m-dihydroxybenzene derivatives and to agents for dyeing keratin fibers containing these compounds.
2. Description of the Related Art
In the area of keratin fiber dyeing, particularly hair dyeing, oxidation dyes have attained substantial importance. In this case, the coloration is produced by reaction of certain developers with certain couplers in the presence of an appropriate oxidant. Suitable developers are, in particular, 2,5-diaminotoluene, 2,5-diaminophenylethyl alcohol, p-aminophenol, 1,4-diaminobenzene and 4,5-diamino-1-(2-hydroxyethyl)pyrazole, and suitable couplers are, for example, resorcinol, 2-methylresorcinol, 1-naphthol, 3-aminophenol, m-phenylenediamine, 2-amino-4-(2′-hydroxyethyl)aminoanisole, 1,3-diamino-4-(2′-hydroxyethoxy)-benzene and 2,4-diamino-5-fluorotoluene.
The oxidation dyes used for dyeing human hair must meet numerous requirements in addition to that of being able to produce colorations of the desired intensity. For example, these dyes must be harmless from a toxicological and dermatological standpoint, and the hair colorations obtained must have good light fastness, resistance to permanent waving, acid fastness and rubbing fastness. In any case, however, in the absence of exposure to light, rubbing and chemicals, such colorations must remain stable over a period of at least 4 to 6 weeks. Moreover, by combining appropriate developers and couplers, it must be possible to create a wide range of different color shades.
Attempts have already been made to improve the properties of m-dihydroxybenzenes by introduction of substituents. Thus, for example, resorcinols substituted in the 4-position are known from European Unexamined Patent Application EP 0 904 774 and WO Unexamined Patent Application 99/15148. Moreover, German Unexamined Patent Applications DE 30 016 905 and DE 198 59 800 teach the use of substituted m-dihydroxybenzenes in oxidation hair colorants. With the currently known dyeing agents, however, it is not possible to meet the requirements placed on dyeing agents in all respects. Hence, the need continued to exist for novel couplers that would meet the aforesaid requirements to a particularly high degree.

1,3-Dihydroxybenzene derivatives and colorants containing said compounds

Abstract: wherein R′1 denotes a substituted pyridyl group, a pyrimidyl group, a group of formula (IIa) or (IIIa)

Abstract: and the dyeing agents for keratin fibers containing these compounds.


An apparatus and method for allocating a bandwidth for up-stream data transmission to a plurality of Optical Network Units (ONUs) in an Ethernet Passive Optical Access Network (EPON) in which the ONUs are connected to a single Optical Line Terminal (OLT) are disclosed. The bandwidth allocation method for guaranteeing a Quality of Service (QoS) in the EPON includes the steps of: a) classifying up-stream data to be transmitted from a plurality of Optical Network Units (ONUs) of the EPON to an Optical Line Terminal (OLT) into a plurality of classes according to predetermined data priority information, and requesting bandwidths required for individual classes from the OLT; b) allowing the OLT to perform a bandwidth distribution process according to bandwidth requirement quantities of individual classes using weights pre-assigned to individual classes; and c) allowing the OLT to distribute a residual bandwidth acquired after the bandwidth distribution process is performed from among an available total up-stream bandwidth to the ONUs.

1. Field of the Invention
The present invention relates to an Ethernet Passive Optical Access Network (EPON) system, and more particularly to an apparatus and method for allocating a bandwidth for up-stream data transmission to a plurality of Optical Network Units (ONUs) in the EPON system in which the plurality of ONUs are connected to a single Optical Line Terminal (OLT).
2. Description of the Related Art
Typically, an Access Network (AN) is indicative of a communication area positioned between a service provider (e.g., Central Office (CO), a Head-End, or a Point-of-Presence (POP), etc.) and a service subscriber capable of receiving a specific service from the service provider.
Presently, a variety of networks are widely used as the aforementioned Access Network (AN), for example, currently xDSL networks (e.g., an Asymmetric Digital Subscriber Line (ADSL), and a Very high-data rate Digital Subscriber Line (VDSL)) based on a telephone line via which low-speed data and voice-oriented data are processed, and a Hybrid Fiber Coaxial (HFC) network serving as an optical/coaxial hybrid network, etc.
However, as technologies of a high-speed Internet, a high-speed LAN (Local Area Network), and a home network have recently been developed, and a variety of applications (e.g., a voice data service and a multimedia streaming service, etc.) required for the aforementioned technologies have been rapidly developed, an amount of a bandwidth required for an Access Network (AN) is rapidly increased, and the xDSL network based on a telephone line and the HFC network based on a coaxial cable cannot satisfy the aforementioned rapidly-increasing AN bandwidth requirement.
With the increasing development of a variety of communication services such as VOD-, CATV-, and HDTV-services, such that many developers have recently conducted intensive research into the implementation of high-speed Internet traffic and an Access Network (AN) which uses an optical line in a Broadband Convergence Network (BCN) environment. Specifically, a Passive Optical Network (PON) system has long been considered to be the most appropriate alternative network for an FTTx (Fiber To The x) scheme in technical-, economical-, and evolutional-aspects of communication networks.
Although the PON system and associated technologies have been initially developed for an Asynchronous Transfer Mode (ATM) network, the ATM PON (APON) based on ATM technologies has not been widely used by users due to a variety of problems (i.e., system complexity, high costs, Ethernet-based subscriber traffic increase, and difficulty of video service accommodation, etc.). Recently, the EPON (Ethernet PON) standardization based on the IEEE 802.3ah EFM (Ethernet in the First Mile) task force has been completed. The EPON technology transmits an Ethernet frame to a destination without modifying a protocol of the Ethernet frame in a passive optical line arranged between a subscriber and a Central Office (CO), such that it is more cost-effective than conventional networks based on telephone- and coaxial-lines. As a result, many developers have recently conducted intensive research into the aforementioned EPON technology, and a variety of companies have currently manufactured chips capable of satisfying a prescribed EPON standard. Recently, a variety of Access Networks (ANs) based on the EPON system have rapidly come into widespread use.
FIG. 1 is a block diagram illustrating a structure for transmitting up-stream data and down-stream data in a conventional Ethernet EPON system, and its operation principles.
Referring to FIG. 1, a conventional EPON system includes an Optical Line Terminal (OLT) 100, a splitter 105, and a plurality of Optical Network Units (ONUs) 110, 120, and 130. The EPON system includes a PTM (Point-To-Multipoint) structure in which the ONUs 110, 120, and 130 share the OLT 100 via a single optical fiber. In other words, a down-stream transmission scheme for transmitting data from the OLT 100 to the ONUs 110, 120, and 130 is implemented with a broadcast scheme. On the contrary, an up-stream transmission scheme for transmitting data from the ONUs 110, 120, and 130 to the OLT 100 is implemented with a MTP (Multipoint-To-Point) scheme.
The OLT 100 is located at the CO (Central Office). The ONUs 110, 120, and 130 collect subscriber traffic generated from a plurality of subscriber terminals (also called user terminals) 140˜145. The splitter 150 connects the single OLT 100 to the plurality of ONUs 110, 120, and 130 according to a specific ratio of 1:N, such that an optical distribution network between the OLT 100 and the ONUs 110, 120, and 130 is formed. Down-stream traffic 160 configured in the form of broadcast data is transmitted to a destination in the EPON system, such that it is similar to conventional Ethernet traffic. However, the up-stream transmission is implemented when the ONUs 110, 120, and 130 simultaneously transmit the up-stream traffic 150 to the single OLT 100. For example, the OLU 110 for use in the EPON system shares network resources with other ONUs 120 and 130 to transmit up-stream traffic L1, and the OLT 100 controls access authority of the shared network resources of the ONUs 110, 120, and 130. Therefore, a method for evenly and effectively allocating a bandwidth and a Multi Point Control Protocol (MPCP) are employed, such that they prevent an unexpected data collision from being generated when a tree-structure EPON system transmits up-stream data, and an effective bandwidth allocation process is executed. The easiest method from among a plurality of up-stream data transmission methods is a fixed bandwidth allocation scheme capable of dividing a bandwidth into sub-bandwidths according to the number of the registered ONUs 110, 120, and 130, and allocating the sub-banwidths to the ONUs 110, 120, and 130, respectively.
However, the fixed bandwidth allocation scheme has difficulty in supporting Quality of Service (QoS), and cannot provide individual ONUs 110, 120, and 130 with different bandwidths instead of the same bandwidths although there is a spare bandwidth in an overall bandwidth. A variety of dynamic bandwidth allocation methods have been proposed to obviate the aforementioned problems of the fixed bandwidth allocation scheme. A representative method from among the dynamic bandwidth allocation methods is an Interleaved Polling with Adaptive Cycle Time (IPACT) method. The IPACT method enables the OLT 100 to transmit a gate message to the next ONU 120 according to down-stream transmission before a current ONU 110 having transmission authority performs the last transmission. In more detail, if individual ONUs 110, 120, and 130 performs up-stream data transmission according to the gate message of the OLT 100, they inform the OLT 100 of buffer information of the ONUs 110, 120, and 130, such that the dynamic bandwidth allocation process can be performed. However, although the IPACT method provides different bandwidths according to the buffer information of the ONUs 110, 120, and 130, it can distinguish individual traffic requirement characteristics from each other on the condition that a variety of traffics having different characteristics are mixed, such that it has difficulty in providing an appropriate QoS.

Bandwidth allocation device for guaranteeing QoS in ethernet passive optical access network

Electronics and Telecommunications Research Institute


A latch is designed to attain and keep full engagement of a sub-assembly in a chassis and to increase the reliability and longevity of connectors by increasing the chances that they remain fully engaged even in the presence of shock and vibration.

Some electronic module sub-assemblies need to be inserted into a chassis and then be connected and fully mated with a chassis-mounted connector. Examples of such sub-assemblies are power supplies, RAID disks, peripheral devices, fan assemblies, and processors, all of which require a power connection of some sort. When these sub-assemblies have a power connection there is a requirement for sufficient surface contact (barrel contact) to insure adequate performance. Sufficient surface contact is only accomplished and assured with a fully mated or almost fully mated connector.
Providing for full connector insertion of power connectors (pre-loading) is of vital importance when preventing power failures as is maintaining the fully loaded connection during service. If a power connector loosens or begins to back out and there is less and less surface contact, the power connection and the connector itself may eventually fail. Consequently, yield (longevity and service life of the connector and thus any product) is compromised by a non-fully inserted power connector.
For purposes of quality and safety, and especially with high voltage, one typically uses an injector tool when inserting a sub-assembly into a chassis, usually then securing the sub-assembly with a lock of some kind and a mounting screw or two.
Previous solutions include securing screws, locking inserter/ejector levers, and simple locking mechanisms (like a door handle).
Securing screws can be used to provide enough pre-load to ensure fully mated connectors. The problem is they are often numerous in number and are subject to stripping or cross threading due to alignment problems. There are also tolerance problems in getting the threads started. The screw stripping, screw binding, and screw damage sometimes leaves metal particles and slivers that can short electronics near the failure. Furthermore, since the screws are not initially attached to the chassis or sub-assembly, they can be easily lost or misplaced. Sometimes when this happens, a sub-assembly is secured with less than the full number of required screws, and the connection is either not as complete as it needs to be initially or is prone to earlier failure.
Inserter/ejector levers themselves are adequate to fully engage a connector pair at time of insertion. The problem is that they generally cannot provide enough pre-loading to overcome extended field shock and vibration, especially in the telecom environment. Furthermore, they generally cannot maintain full engagement during fragility operations such as transportation and shipping because there is no pre-loading spring action.
Simple locking mechanisms do not provide any pre-load, and thus are inadequate for powered sub-assemblies, especially when the service environment includes shocks and vibrations.

Hewlett-Packard Development Company, L.P.


A reference circuit for coupling to a particular type of BiCMOS logic gate includes a V.sub.be multiplier coupled between V.sub.CC and a first internal node. The multiplier establishes a predetermined potential at the internal node which determines the voltage swing across the PMOS load devices utilized in the BiCMOS logic gate. A first PMOS transistor, configured as a current source within the multiplier, has its source coupled to the internal node. A second PMOS transistor has its gate coupled to the gate and drain of the first PMOS transistor in a source-follower configuration so as to drive the source node of the second PMOS transistor to the predetermined potential. A reference PMOS transistor is coupled between V.sub.CC and the source node of the second PMOS transistor, with the gate of the reference PMOS transistor being commonly coupled to the gates of the PMOS load devices and to a reference potential. A NMOS current source device is coupled to the source of the second PMOS transistor such that a reference current flows through the reference PMOS transistor; this current is then mirrored through the PMOS load devices of the BiCMOS logic gate.

Circuits which combine bipolar and complementary metal-oxide semiconductor (CMOS) devices on the same silicon substrate are known as BiCMOS circuits. BiCMOS logic circuits share the advantages of both CMOS and bipolar circuitries. For example, BiCMOS circuits are characterized by extremely low quiescent power consumption, rail-to-rail output capability, high-density and high input impedance. At the same time, the bipolar elements provide very fast switching capabilities and feature good performance over temperature and power supply variations.
Emitter-coupled logic (ECL) is a popular family of bipolar logic circuitry which is found extensively in the prior art. Lately, researchers have attempted to create low cost BiCMOS ECL logic gates in order to take advantage of the faster bipolar logic switching capabilities while minimizing the quiescent power consumption by utilizing CMOS circuit devices. Whereas ECL processes can fabricate resistors for ECL circuits, BiCMOS processes typically do not include a resistor device, and must utilize CMOS devices instead. For example, U.S. Pat. No. 5,124,580 describes a BiCMOS logic circuit which includes an emitter-coupled pair of bipolar transistors connected to differentially compare an input signal with a reference potential. Each of the transistors is loaded by a p-channel MOS (PMOS) transistor operated in its linear region.
One of the drawbacks of prior art BiCMOS ECL logic circuits has been the inability to provide an appropriate reference circuit which maintains the PMOS load transistors in a linear region despite variations in current, temperature, process etc. Often, the difficulty lies in having the PMOS load devices track with the n-channel MOS (NMOS) devices which are typically used as current sources. Another problem has been the use of large voltage swings, sometimes as large as the power supply voltage, for switching between the logic voltage levels. Most crucial is the fact that large voltage swings add delay to the circuit, thereby diminishing performance. One of the advantages of ECL is that it uses small voltage swings. The large (power supply voltage) swings used in CMOS circuits add delay to the circuit, thereby diminishing performance. These large swings also generate more noise.
Yet another related problem occurs when the input voltage exceeds the output swing. This typically causes saturation of the input bipolar transistors, which also slows the device's speed considerably. At the other extreme, if the voltage swing is too small there can be a problem in maintaining a sufficient noise margin. Of course, all of the aforementioned problems are exacerbated by variations in temperature, voltage, and processing.
As will be seen, the present invention provides a reference circuit in conjunction with a BiCMOS ECL gate that allows the use of controlled, small voltage swings, and emitter-following to increase the speed of the logic gate.

Reference generator circuit for BiCMOS ECL gate employing PMOS load devices


A water jet propulsion device for a vessel in which a suction inlet 4 is open at a vessel bottom part in a vicinity of a stern, water suctioned from the suction inlet 4 to a suction duct 5 is pressurized by a spiral blade 10 provided in an impeller housing 6, and jet water is ejected from an ejection duct 13 backward of the stern, and moreover, on an impeller shaft 7 provided in the impeller housing 6 are disposed a plurality of those spiral blades 10 with slipped phases, outer peripheral parts 10b of the spiral blades 10 are close to an inner circumferential surface of the impeller housing 6, and outer circumferential end parts 10c of the spiral blades 10 are extended to a suction side, and further in a fluid passage behind the spiral blades 10 are provided guide vanes 12, and cavitations and a rolling of a vessel body in a high-speed travelling are reduced, and a travel performance is improved.

As conventional propulsion devices for vessels of this type, there are known ones (for example, Japanese Utility Model Publication No. 1-27517) in which the propeller is made like a leaf, a plurality of those propellers are arranged on a propeller shaft, and the propellers have outer tubes provided on outer peripheral parts thereof for giving pressures.
Moreover, there is described in the Specification of Japanese Patent Application Laid-Open Publication No. 5-270486 a device that has a rotatable guide vane provided at a suction inlet of a suction duct, for changing the direction of inflowing water to the suction duct. Further, the Specification of Japanese Utility Model Publication No. 1-29200 has described therein also a device provided with a guide vane for guiding external water to a fin projected under a suction inlet. Furthermore, in Japanese Patent Publication No. 56-40078 for example, there is described also a device in which, when the propulsive force is reduced with drift matters adhering to a grid of a suction inlet, a fork-like member is rearwardly rotated to remove the drift matters.
Still more, there is described in Japanese Patent Application Laid-Open Publication No. 5-278683 also a propulsion device in which a deflection plate is provided at a bottom opening of a steering column, and jet water is frontwardly deflected with a rotatable flap.
However, in conventional water jet propulsion devices, although high-speed travel is permitted, as the blade width of an impeller is short, there is a problem that vortices occur with an increase in number of revolutions of the impeller. Still less, as the travel speed becomes high, the inflow rate of water incoming to a suction duct at a headway direction side decreases, developing low-pressure stream regions, causing cavitation phenomena on blade surfaces of the impeller, so that there may be vibrations and noises and a concurrent roll. And, in a device which has as a measure for prevention of cavitation a mobile guide vane provided at a suction inlet for changing the inflow direction to a suction duct, it may constitute an obstacle to inflowing water in high-speed travel. And, in a device which has a guide blade provided outside a suction inlet, though being able to increase the inflow rate to a suction duct, it may constitute a water fluid resistance, as the vessel moves astern or makes a turn, failing to achieve a rapid directional change.
Further, in a device provided with a grid at a suction inlet, although it has a favorable removability to solid bodies such as a driftwood, those drift matters which have a flexible nature may adhere to the grid or flow into a suction duct, binding an impeller, with a lowered performance causing a reduced propulsive force or a failure to travel. And, in a device in which adhering drift matters are removed from a grid, there is needed a speed reduction of a vessel, in addition to a manual operation. Yet less, in a device which has at a bottom part of a steering column a deflection plate provided for a reverse propulsion guide, it may constitute a water fluid resistance in high-speed travel. The invention of the present application has for its object to provide a propulsion device with improved suction performance and improved travelling performance, and a water jet propulsion device which removes drift matters adhering to a grid, while travelling, and which is small of a reduction in reverse propulsive force, when travelling astern, and free of a sudden braking nor a lateral slip, when performing a change between a forward movement and a backward movement.


An active acoustic attenuation system prevents overdriving of the canceling output transducer or speaker (14) by shunting at least part of the correction signal (46) to a parallel shunt path (306) and away from the output transducer (14) Variable gains (308 and 310) are provided in the shunt path (306) and the input to the output transducer (14) for varying the ratio between the part of the correction signal (46) supplied to the output transducer (14) and the part of the correction signal (46) shunted to the shunt path (306). A first adaptive filter model (40) has an error input (202) from the error signal and outputs the correction signal (46). A second adaptive filter model (142) models the output transducer (14) and the error path (56) between the output transducer (14) and the error transducer (16). A copy (312) of the second model (142) has an input from the output (46) of the first model (40), and the output of the copy (312) is summed with the error signal (44) and the resultant sum is supplied to the error input (202) of the first model (40), such that the shunt path (306) is provided through the model copy (312).

The invention relates to active acoustic attenuation systems, and provides a system for limiting output power of the correction signal to the canceling output transducer.
The invention arose during continuing development efforts relating to the subject matter shown and described in U.S. Pat. Nos. 4,677,676, 4,677,677, 4,736,431, 4,815,139, 4,837,834, 4,987,598, 5,022,082, and 5,033,082, incorporated herein by reference.
Active attenuation involves injecting a canceling acoustic wave to destructively interfere with and cancel an input acoustic wave. In an active acoustic attenuation system, the output acoustic wave is sensed with an error transducer such as a microphone which supplies an error signal to a control model which in turn supplies a correction signal to a canceling output transducer such as a loudspeaker which injects an acoustic wave to destructively interfere with and cancel the input acoustic wave. The acoustic system is modeled with an adaptive filter model.
In some applications, the acoustic pressure level of the input acoustic wave may exceed the ability of the canceling output transducer to cancel same. An example is a sudden change in the input noise level, for instance sudden engine acceleration in automotive exhaust silencing applications. During this condition, the active noise controller may become unstable if it is allowed to adapt and output a correction signal which is beyond the capability of the canceling loudspeaker or otherwise attempt to overdrive same. When the input noise decreases to normal levels, e.g. upon termination of the sudden acceleration, the control model will have to re-adapt and converge new weight update coefficients.
In one aspect of the present invention, overdriving of the canceling output transducer is prevented by engaging a power limiting function which is accomplished by shunting at least part of the correction signal to a shunt path and away from the output transducer. The shunt path is in parallel with the output transducer and when engaged at high input noise levels enables the adaptive filter model to remain stable and converged, with part of the correction signal still going to the canceling output transducer and the remainder of the correction signal going through the shunt path around the output transducer, while the adaptive filter model continues to adapt.
In another aspect, variable gains are provided in one or both of the shunt path and the input to the output transducer. The ratio between the part of the correction signal supplied to the output transducer and the part of the correction signal shunted to the shunt path is varied.
In another aspect, a second adaptive filter model is provided and models the output transducer and the error path, and the shunt path is provided through a copy of such second model.
In another aspect, the power limiter is engaged when the part of the correction signal supplied to the output transducer exceeds an engagement threshold, and is disengaged when a calculated correction signal, theoretically needed for full cancellation, decreases below a disengagement threshold. If the part of the correction signal supplied to the output transducer is greater than a given range, then the part of the correction signal supplied to the output transducer is decreased and the part of the correction signal shunted to the shunt path is increased. If the theoretically needed correction signal is less than another given range, then the part of the correction signal supplied to the output transducer is increased and the part of the correction signal shunted to the shunt path is decreased.

Active acoustic attenuation system with power limiting