The present invention provides a power source protection device comprising a switching circuit and an overload circuit coupled between the switching circuit and power source for driving the switching circuit to limit current stopping the increase in the current output by the power source. Thus, the device is protected against overcurrent damage and maintains stable system operation.

1. Field of the Invention
The present invention is relates in general to a protection device for a power source, and more specifically to the use of a switching circuit, an overload protection circuit, and a short protection circuit for protecting an electronic device.
2. Description of the Related Art
The simplest current limiting component is a fuse, and it can be used alone or with a protection component. The fuse is capable of preventing over current impact, hence it is essential to a system as it is the final defense against system breakdown.
Presently, there are two electron protection components for power supplies in common use. One is a general fuse, which has the drawback of only one time use, and requiring replacement change after burning out. Thus, it used a chance exists that must be returned to the manufacturer for maintenance.
Another type protection component is a poly switch, which possesses the advantage of continuous use after providing the protection function, with the defect of high operational temperature. FIG. 1 is a conventional temperature and current diagram of poly switch. A represents the characteristic curve of model nanoSMD, microSMD or miniSMD, B represents the characteristic curve of the model SMDH160. The protection current of poly switch increases with a temperature in the surrounding area causing the working range of voltage to be limited by the temperature in the FIG. 1. A poly switch, however, can be used continuously and only requires periodic replacement, thus it offers an advantage over the standard fuse.
The description of a poly switch is as follows. The poly switch can protect against circuit damage by adjusting itself resistance when high current occurs. Once the current goes back to predetermined level, the poly switch automatically reverts to the normal level of resistivity. These operational characteristics of the poly switch make it rational the ideal choice for power supply and communication applications, due to the fact that changing a battery or connecting device with USB plug may generate instant high current. The poly switch typically replaces traditional glass fuse in some circuits, but is used for mainly in USB applications.
The general fuse stops current by melting and the poly switch limits current by adjusting its impedance according to current passing. Both must be triggered by over current heat to implement the protection function in the induction circuit.
The general fuse and poly switch solutions are in widespread use, however, there is limitation above. Therefore, the present invention provides better temperature characteristics than a poly switch for limiting the current and stopping the output of a power source, and without replacement every time over current occurs.

Protection device for power source and electronic device


Techniques are described for compensating for distortion effects caused by projecting images to a surface that is non-perpendicular to a raster-scanning laser projector. Pixel size is modulated such that smaller pixels are projected to farther portions of the surface, and larger pixels are projected to nearer portions. Pixels within a raster scan line may have their lengths modulated through variation of a frequency of light source that generates the pixels, or through adjustment of a scan speed along the line. Pixel heights may be adjusted by modulating the distance between scan lines. Scan speed and distance between scan lines may be modified by controlling micromirrors incorporated into the laser projector for directing the light projection.

Projectors are used in many scenarios to create a visual display of information on a surface. However, when the projector is not parallel to the surface (e.g., when the line of projection from the projector to the surface is not perpendicular to the surface), the projection may be distorted. For example, when a projector is sitting on a table facing upward toward the projection surface, the projected image appears larger at the top than at the bottom. This distortion effect is commonly referred to as the keystone effect, given that the effect tends to distort the projected image into a trapezoid shape (i.e., the shape of an architectural keystone).


A connector axial compression tool having a lever end and a cable end, with a body slidably supporting a cradle in a cavity formed in the body. The cradle is slidable via a handle which pivots about the body, linked to the cradle by a lever mechanism. The cradle has a shoulder clamp adapted to mate with a connector body. Operation of the handle moves the cradle towards and away from a cable end of the cavity, against a cable clamp through which the cable may pass but against which a cable clamp sleeve of the connector abuts, axially compressing the connector to couple it to the cable. Because the shoulder clamp holds the connector body rather than pressing against the connector interface, a wide range of different connectors may be used with the same tool, without causing damage to the connector interface of the various connectors.

1. Field of the Invention
This invention relates to a tool for installation of electrical connectors upon an electrical cable. More particularly, the invention is concerned with an axial compression tool, which accepts electrical connectors having a range of different connector interfaces.
2. Description of Related Art
There have been advancements in connectors adapted for installation by compression fit. U.S. patent application Ser. No. 10/708,278 "Axial Compression Electrical Connector" filed Feb. 20, 2003 by Islam et al, assigned to Andrew Corporation of Orland Park, Ill., as is the present invention, describes several embodiments of such connectors. Electrical connectors adapted for installation upon electrical cables by axial compression are field installable using an axial compression hand tool. The prior axial compression tools typically comprise a lever action, which actuates a chuckhead towards the connector interface of the electrical connector. The electrical cable and the electrical connector are fed through a stop against which the chuckhead actuates to axially compress the connector components together, permanently forming the electrical connection between the connector body and the electrical cable.
The prior chuckhead is adapted to engage the electrical connector at the face of the connector interface. Therefore, the prior tools are typically supplied dedicated to a specific connector type, such as Type F, and or include a range of different exchangeable chuckheads, one for each desired connector interface. Maintaining a range of different connector interface specific tools and or exchanging the chuckheads as different connector interfaces are encountered, increases installation tooling requirements and labor costs.
If there is any axial misalignment during the compression, the chuckheads may damage the inner conductor, sealing, and or insulator assemblies of the connector interface. Also, the compression force may push the inner conductor into the cable and away from the connector. This also may result in unnecessary labor and costs to repair and or replace any damaged components of the electrical connector and electrical cable assembly.
Competition within the electrical connector industry has focused attention on equipment and tooling costs, as well as time requirements for installation of electrical connectors.
Therefore, it is an object of the invention to provide an apparatus that overcomes deficiencies in the prior art.


A microprocessor-based integrated circuit for smart cards includes an application software layer and a peripheral management system including an intermediate software layer to manage the hardware processes on peripherals of the integrated circuit that are called up by at least one process of the application software layer.

One integrated circuit for a smart card type application is commonly called a microcircuit or an electronic micromodule. In addition to a microprocessor, a microcircuit includes a number of other hardware resources, generally called peripherals, such as counters, serial interface circuits, random-number generators, clock-signal generators, etc. Also, memories are usually provided, particularly a read only program memory (ROM), electrically erasable programmable read only memories (EEPROMs) for storing application data, or working memories such as random access memories (RAMs). It has also been the practice to have a peripheral access controller that manages the address and data buses with the peripherals.
An integrated circuit of this kind is commonly delivered to a customer who is not necessarily the final user. For this customer, at least one application has been implemented in this integrated circuit, depending on its final purpose. The present trend is towards the implementation of several applications at a given time, one of which is activated by an external application.
These applications may be of different types. They may be, for example, a smart-card operating system, a cryptographic library that could be used for computations or signature verification, enciphering, or incorporated test software. This list of applications is not exhaustive.
These applications are implemented in the integrated circuit in the form of software processes in an application software layer. These processes are executed by the microprocessor of the integrated circuit. To perform certain operations of a given software process, the application software layer must call up processes in the peripherals, hereinafter referred to as hardware processes (as opposed to software processes).
Usually, the application software does so directly, i.e., it directly manages the peripherals of the integrated circuit. To this end, the integrated circuit manufacturer provides all the necessary information, including the addresses of the different peripherals of the integrated circuit, the addresses (in ROM program memory) of the tables of the hardware interrupt vectors, etc. These pieces of information are specific to the integrated circuit. They enable the application software layer to directly call up the hardware process on a peripheral. They also enable the software layer to manage the peripherals in interrupt mode. This means that it can continue to work for as long as the peripheral has not finished executing a requested hardware process (e.g., the programming of an EEPROM memory page).
In this case, it is the application software layer that directly manages the hardware interrupts sent by the peripherals. This implies that it must read and write registers and access the table of the hardware interrupt vectors in the ROM program memory to identify an interrupt source and undertake the necessary action.
Of course, further improvements in the security of the smart cards are constantly being sought in an attempt to prevent any use of these cards for fraudulent purposes.

Method for the management of peripherals in an integrated circuit


An exhaust apparatus and a high vacuum pumping unit including a high vacuum device and an auxiliary vacuum pump are disclosed, wherein a high vacuum is achieved in a vacuum vessel such that the gas molecules within the vacuum vessel are ionized and accelerated to be exhausted. In the high vacuum pumping unit, those gas molecules are diffused back or released from the vacuum pump are ionized and accelerated to be returned to the vacuum pump.

1. Field of the Invention
The present invention relates to an exhaust apparatus and a vacuum pumping unit including the exhaust apparatus, which are specifically adapted for discharging a gas in a vacuum vessel to produce an ultrahigh vacuum in the semiconductor process or the like.
2. Prior Art
FIG. 12 conceptionally illustrates the prior art vacuum equipment including a high vacuum pump, wherein a vacuum chamber 1 is connected to a vacuum pump 2 through an exhaust pipe 3. The vacuum pump 2, which comprises, for example, a turbo molecular pump, on oil diffusion pump, an ion pump and the like and, exhausts only the gas molecules which fly into the exhaust pipe 3 from the vacuum chamber 1.
However, in the above-constructed vacuum equipment, when a turbo molecular pump is used to exhaust a gas with a low compression ratio such as hydrogen, helium or the like, gas molecules may diffuse back to a high vacuum side i.e. to the vacuum chamber 1 and, thus causes a decrease in the vacuum level.
In the case of an oil diffusion pump, the gas molecules, which were once exhausted by the pump, may flow back into the vacuum chamber and further, the vapor of pumping oil heated also diffuses back. Thus, the vacuum level decreases.
In the case of the ion pump, gas molecules absorbed into a titanium wall of the pump are released and flow back into the vacuum chamber, thus reducing the vacuum level.
In the prior art, no effective means were available against the back diffusion of gas molecules with a low compression ratio or released gas molecules from the vacuum pump. Nevertheless, oil vapor from the oil diffusion pump may be prevented only by providing a cold trap with liquid nitrogen. However, complete prevention for any counterflow has been very difficult.


This invention relates to processes for forming hydrogen mediated saline hydride initiated anionic polystyrene distributions via novel polymerization conditions. This invention also relates to novel hydrocarbon soluble super active saline hydride catalyst and reagent compositions useful in conducting the hydrogen mediated saline hydride initiated polymerizations of this invention. This invention also relates to novel low molecular weight polystyrene polymer composition formed exclusively from styrene and molecular hydrogen as the monomers.

Low molecular weight—Mw<<4000 Daltons—polystyrene compositions are useful in a variety of applications both in their end use such as polymer slip reagents (see EPO 741147) or as substrate precursor's for further synthetic derivatization. Such synthetic derivatization generally conducted through aromatic electrophilic substitution reactions (see: U.S. Pat. No. 8,217,120B2 "Functionalized styrene oligomers and polymers"). Anionic chain transfer polymerization of polystyrene provides an economic benefit due to the cost-effective efficient use of the anionic chain transfer catalyst when forming low molecular weight polystyrene compositions due to the use of substantially reduced amounts of organolithium reagents and other alkali earth metal regents used in forming the chain transfer initiator and catalyst. Accordingly, methyl benzene compounds (toluene). polymethylbenzene compounds (xylenes, mesitylene, durene, etc.) are excellent chain transfer agents for forming low molecular weight polystyrene compositions suitable for further synthetic elaboration. Such methyl benzene chain transfer agents owe in part their effectiveness because the pKa of such compositions are generally at least one order of magnitude lower than that of a poly(styryl) anion's conjugate acid. Other alkyl substituted benzenes, ethylbenzene in particular, have been reported (EPO 741147) or at least suggested to be suitable organic chain transfer agents for forming anionic chain transfer styrene distributions using catalyst formed from potassium t-butoxide, butyllithium and TMEDA. Regardless of the method of forming an anionic chain transfer distribution, it is desirable to form low molecular weight polystyrene compositions free or essentially free of such organic chain transfer agents.
TABLE IPrior Art EPO 741147 Anionic Chain Transfer Styrene Polymerization w/Ethylbenzene as the Chain Transfer AgentEPO 741147 Example #1234567Cyclohexane Diluent (ml)0155815581558155815581558g Cyclohexane/g Styrene00.360.360.960.960.960.36Mole K:Mole Li1:11:11:11:11:11:11:1Mole Styrene/mole0.447.037.037.0914.1814.1818.86EthylbenzeneMole Styrene/hr/mole0.020.318.104.22.1682.361.05EthylbenzeneMole Styrene/hr/mole10.6710.6631.9832.0664.1232.0621.30LithiumMn164876121293221371736596Mw262197004180015004830375033300MzNRNRNRNRNRNRNRPD1.6022.5034.501.612.262.1655.90Standard Deviation12740607013728239918704414σn = (MwMn − Mn2)1/2
From the experimental details of EP 0 741 147 A1, as presented in Table I above, it can be seen by comparison of EP 0 741 147 Examples 2-7 that only Example 4 produced an anionic chain transfer styrenic reaction polymer distribution (ACTSR distribution) having limited breadth (standard deviation) and small polydispersity. Minor changes in the relative feed rates or charges as reported, or both simultaneously, resulted in ACTSR distributions having very large standard deviations and having polydispersity that increase significantly, and in some Examples, astronomically. Thus, it can be seen that from such experimental details, a very narrow and limited process window for producing distributions with narrow breath, i.e., small standard deviation σn is provided. Investigations of this prior art technology reveals that the process technology suffers from the undesirable formation of a catalyst composition of low or limited solubility in the hydrocarbon reaction medium. The process also relies on very slow relative feed rates conducted over long feed times (6 to 18 hours) in order to attempt to equilibrate living and dead polymer chains. The principle problem with ethylbenzene as a chain transfer agent is that the pKa of ethylbenzene is of the same order of magnitude as that the conjugate acid of a poly(styryl) anion. It is desirable to have a new catalyst and anionic chain transfer polymerization conditions that can provide lower molecular weight polystyrene distributions under more economical use of reagents as well as shorter time periods and thus more productivity of the polymerization reactor.
Polymerization of styrene under a hydrogen atmosphere is known for Zeigler Natta polymerization of styrene (Murahashi, S.; Nozakura, S.; and Utsuhara Y. "Polymerization of Styrene with the Ziegler-Natta Catalysts in the Presence of Molecular Hydrogen." Bulletin of the Chemical Society of Japan 1960 33 431). Additionally there is at least one report of for metallocene polymerization of styrene under a hydrogen atmosphere (Ref. 14: Tomotsu, N., Kuramoto, M., Takeuchi, M., & Maezawa, H. (1996). Metallocenes 1996, 96, 211. (i) Chien, J C W.; in Tomotsu, N., et al. "Syndiospecific Polymerization of Styrene." Journal of Molecular Catalysis A: Chemical 1998 128.1 167). In both polymerization chemistries formation of the hydrogenation product of styrene—ethylbenzene—is mentioned. Thus Utsuhara and coworkers reported that isotactic polystyrenes of low molecular weight could be obtained in the presence of hydrogen, although in addition to this there was found another reaction which is competitive to the polymerization reaction, i. e. hydrogenation of styrene to ethylbenzene. In both approaches—Ziegler Natta and metallocenes catalysis—to hydrogen mediation of styrene polymerization ethylbenzene is kinetically inert and represents an unrecoverable yield loss.
Deffieux and coworkers report the hydrogenolysis of poly(styrl)lithium distributions (50° C. H2 1 atm) leading to the in situ formation of lithium hydride capable of reinitiating styrene anionic polymerization at 100° C. (Ménoret, S., Deffieux, A., & Desbois, P. "Initiation of retarded styrene anionic polymerization using complexes of lithium hydride with organometallic compounds." Macromolecules, (2003) 36, 5988). Deffieux further reports that: "However, the slow addition of LiH to styrene with respect to propagation yields incomplete initiation." Deffieux reports that with addition of an added organometallic reagent (n,sec-Bu2Mg, or BuMgOBT or i-Bu3Al) the solubility and reinitiation efficiency of the LiH is improved but the catalyst efficiency is only between 50% and 150%. Furthermore the bimetallic complex formed decreases the rate of termination and the half-life of the active or living poly(styryl)lithium species is greatly increased from 40 min for uncomplexed poly(styryl)lithium to 34 hours for the bimetallic complexed poly(styryl)lithium at 50° C. in cyclohexane and 1.1 atm H2. In fact they report that it requires 50 atms H2 to restore the half-life of the living poly(styryl)lithium species to 50 minutes. Deffieux and co-workers teach that soluble lithium hydride is a potential initiator of styrene polymerization:                "Lithium hydride, as long as it remains soluble, is a potential initiator of styrene anionic polymerization, at least at 100° C., even in nonpolar solvent. The efficiency of this initiator is improved by complexation with organometallic derivatives which first ensure its solubility and then reduce the styrene propagation rate. When n,sec-Bu2Mg is used as additive, Li—H bonds are not the real initiating sites, the polymerization proceeding after a ligand exchange between the two metal atoms."        "At high temperature, H2 acts as a chain transfer agent in styrene anionic polymerization. However, to be efficient, its concentration in the medium should be high in order to shift the equilibrium toward the formation of metal hydride. This requires high hydrogen working pressures."However Deffieux and coworkers require complexation of LiH with Lewis acids such as dialkylmagnesium reagents, aluminum alkyls and/or alkylaluminum hydrides to solubilize the LiH. Such complexed LiH reagents thus formed are not efficiently reduced once used to polymerize styrene. Thus such Lewis acid complexed poly(styryl)lithium chains are not efficiently reduced nor do their reduction effectively regenerate a highly active or super active form of LiH initiator.
It is documented in the literature that only two highly soluble Group 1 metal hydrides free of Lewis acid complexing agents are known (see: Stasch, A. and Fohlmeister, L. Aust. J. Chem. 2015, 68, 1190-1201; and Liptrot, D. J., Springer Thesis: Group 2 Mediated Dehydrocoupling, Chapter 2. Group 1-Group 2 Bimetallic Alkyls and Hydrides, Springer International Publishing, 2016, pp. 41-61). These are: (1) the "super aggregate" [(t-BuOLi)16(LiH)17] generated via photolytic decomposition of a mixture of butyllithium lithium t-butoxide (Thomas, D. et. al., J. Am. Chem Soc. 1997, 119, 11998; and Thomas, D. et. al., Angew. Chem. Int. Ed. 1998, 37, 1537); and (2) Stash's hydrocarbon soluble LiH complex, [(DipNPPh2)4Li8H4] (Dip, 2,6-iPr2C6H3), prepared by the application of phenylsilane to a reactive metal precursor (Stasch, A. Angew. Chem. Int. Ed. 2012, 51, 1930.) However this hydrocarbon soluble LiH reagent is not reactive enough to hydrolithiate the very active species diphenylacetylene or 1,1-diphenylethylene. Thus one of ordinary skill in the art would understand that [(DipNPPh2)4Li8H4] would not likely hydrolithiate a styrenic or other vinyl aromatic monomer and consequently would not initiate polymerization of such monomers. Stash also reports the formation of "initially clear solutions" of LiH/Li(pz) (pz=3,5-di-tert-butyl-1H-pyrazole) which turn milky likely due to formation of colloidal LiH. Such "initially clear solutions" are prepared by treating 3,5-di-tert-butyl-1H-pyrazole (pzH) with more than one equivalent of n-butyllithium in aromatic or aliphatic solvents, followed by addition of phenyl- or diphenylsilane to convert the excess alkyllithium groups to hydrides. Stash has prepared the first NaH complex [(pz)6Na7H] by the same synthetic strategy as the LiH/Li(pz) methodology again using the sterically demanding pyrazolate ligand (pz) by the reaction of [Na(pz)], [Na(n-Bu)] and diphenylsilane in aromatic solvents. The application of the same synthetic strategy used to produce [(pz)6Na7H] to form a KH hydride analogue resulted only in the formation of crystalline polymeric [K(pz)]. Thus a stable aliphatic and/or cycloaliphatic and/or aromatic hydrocarbon soluble monometallic, bimetallic or polymetallic alkali (Group 1) metal hydride formed directly from molecular hydrogen, H2, is heretofore unknown.
In their publication (Stasch, A. and Fohlmeister, L. Aust. J. Chem. 2015, 68, 1190-1201) teach the following:                "Well-defined hydride complexes purely of Group 1 metals are very rare and are in fact only known for lithium and sodium so far . . . . Most isolated compounds involving alkali metals and hydridic hydrogen centres are mixed-element systems and are best described as 'ate'-type complexes in which the strongest interaction of the hydride ligand is with the non-alkali metal centre or metalloid . . . . This makes the majority of these 'ate' complexes covalent hydride complexes. The most prominent examples in this compound class are perhaps LiAlH4, NaBH4, and other related commercial derivatives such as L-Selectride®, N-Selectride®, and K-Selectride® (lithium, sodium, potassium tri-sec-butyl(hydrido)borate), or derivatives with sterically demanding ligands." emphasis added.
In contrast to covalent hydrides, saline, or ionic, hydrides are defined by the presence of hydrogen as a negatively charged ion, H−, in combination with an alkali metal or alkaline earth metal. With regard to the addition of other saline hydrides to styrene with concomitant polymerization Deffieux and coworkers provide the following background (ibid):                "To the best of our knowledge, very few papers deal with anionic polymerization of vinylic monomers initiated by metal hydrides. Williams briefly mentioned one styrene polymerization experiment initiated by NaH in hexane at 25° C. However, the initiation efficiency was very low and the conversion reached only 90% after 3 days."
Liao and coworkers reported a form of highly active alkali metal hydrides having nanometric (z 20 nm) particle size distributions (Liao, S.; et. al. Journal of Molecular Catalysis, 1993, 84, 211.) In this paper Liao reports formation of highly active saline hydrides (HASH) from the corresponding alkali metal and hydrogen (1 atm) in THF (40° C.) catalyzed by TiCl4 and naphthalene. Complete conversion to the saline hydride required 2 hours for LiH*, 4 hours NaH* and 28 hours for KH* (the * denoting highly active or super active hydride). These nanometric saline hydrides were found to have some utility in the dechlorination and debromination of certain arylhalides. They were also reported to be active as co-catalyst for the hydrogenation of olefins such as 1-hexene when used in certain transition metal complexes. Turnover frequencies in the range of 0.003 to 45.3 s−1 were reported. Thus highly active alkali metal hydrides (50-300 mol) when used in conjunction of a transition metal catalyst (1 mol) only reduce olefins, no disclosure of polymerization or even dimerization of the olefin is made.
Other applications of nanometric size alkali metal hydrides were later reported by Liao and coworkers (Liao, S.; et. al. Synth. Comm. 1997, 27 3977.) Such applications include the reduction of carbonyl carbon to aldehydes and/or alcohols of benzaldehyde, methyl benzoate, acrolein and the methyl and n-butyl ester of acrylic acid. The reactions were conducted in refluxing THF using a stoichiometric excess of highly active saline hydride—either as NaH* or as KaH*—and reactions times of 0.25 to 15 hours. Of particular interest are the reduction of acrolein (0.3 hour) and methyl acrylate (0.25 hour) with NaH* to yield allyl alcohol in 97% and 96% yield respectively. In another publication Liao and co-workers report that heat treated nanometric LiH, NaH and KH complexed with Cp2TiCl2, CP2TiCl2-MH (M=Li, Na or K), can be used as a catalyst to hydrogenate either styrene (M=Li or Na) or octene (M=K). Nanometric KH with Cp2TiCl2 under one atmosphere H2 did not hydrogenate styrene instead initiated polymerization to form very high molecular weight (MW) polystyrene (Mw=200,000) with a wide range of melting points T=160-180° C. It was further found that nanometric KH alone polymerized styrene, one of ordinary skill in the art would understand that such high MW anionic polystyrene (APS) compositions are the result of inefficient initiation of polymerization thus resulting in formation of only very few living polymer chains which rapidly incorporate the styrene monomer at the expense of the remaining insoluble nanometric KH.
Zhang and co-workers report highly active catalysts for the hydrogenation of styrene (2 ml) in toluene (9 ml) under hydrogen atmosphere at −17° C. to 42° C. (Zhang, M.; et. al. Catal Lett 2008, 124, 146). The highly active catalyst was formed from nanometric sized sodium hydride (20 mg, 8.7×10−4) and 12 different Lewis base free titanocene complexes (0.5 mL of 4×10−4 mol/L i.e. 2×10−7 mol)—NaH*/Ti=4350). Uptake of hydrogen was not observed in two other examples where the titanocene complex contained a coordinating oxygen (ether) or nitrogen (tertiary amine) species. Despite the large excess of NaH* to the titanocene catalyst, no report or even mention is made of the polymerization of styrene much less any form of chain transfer chemistry.
The preparation of super active—extremely finely divided—forms of lithium, sodium and potassium hydrides were reported by Schleyer and co-workers (Schleyer, P. v. R.; et. al. J. Org. Chem. 1987. 52, 4299; and Schleyer, P. v. R.; et. al. Angew Chem Int. Ed. Engl. 1986 25 465.) The preparation of these super active saline hydrides (SASH) as a fine suspension entailed the hydrogenation of the corresponding alkali metal alkyls in the presence of N,N,N′,N′-tetramethylethylenediamine (TMEDA) in hexanes. Formation of super active LiH* was conducted between 30 and 35° C., super active NaH* was prepared under cryogenic conditions (−10° C. to −15° C.), and super active KH* was reported to be formed at −20° C. to −25° C. The application of the hydrides to organic synthesis was explored by Schleyer and reported in the above cited open literature papers. Most of the synthetic reactions (metalations, additions and reductions) were conducted under cryogenic conditions with temperatures as low as −90° C. with a few reactions conducted between room temperature and 50° C. There were also no disclosures in Schleyer to use the hydrides for polymerization of styrenic, vinyl aromatic or conjugated diene monomers much less hydrogen mediation of such polymerization processes.
Harder and coworkers have reported that styrene can be catalytically hydrogenated (20° C., 20 atmospheres H2, 15 hours in benzene) with 2.5 mole % of the organocalcium catalyst, [DIPPnacnacCaH.THF]2 initially formed from phenylsilane, (see. Harder, S., Speilman, J., Buch, F. Angew. Chem. 2008, 120, 9576 also published as Angew. Chem. Int. Ed. 2008, 47, 9434.) The hydrogenation produced ethylbenzene in 85% yield along with a 15% yield of oligomers comprised mostly of styrene dimer with traces of styrene trimers and oligomers. Harder further reports 1,1-diphenylethene is reduced at a low conversion to yield 14% Ph2CHCH3 and 7% dimer in a catalyst formed from 5 mole % butyllithium/TMEDA complex at 20° C., 20 atmospheres H2, 15 hours in benzene. With regard to this reaction the authors make the following statement:                "The reaction catalyzed by commercially available nBuLi/TMEDA proceeded only to low conversion . . . suggesting that, at lower H2 pressures, the heavier alkaline-earth metal complexes are the more efficient catalysts."
Tetrahydrofuran soluble forms of magnesium hydride were produced by Ashby and coworkers from ortho-substituted (2,6-dimethyl- and 2,6-di-isopropylphenoxides) aryloxymagnesium reagents and an active form of solid magnesium hydride. Tetrahydrofuran insoluble forms of magnesium hydride resulted from alkoxymagnesium reagents and the solid magnesium hydride reagent (see Ashbey, E. C., Goel, A. B., Lin, J. J. Tetrahedron Letters, 1977, 3133.) Ashby also reported the formation of tetrahydrofuran soluble dialkylaminomagnesium hydrides a series of bulky dialkyl and alkylsubstituted cycloalkyl secondary amines and an active form of solid magnesium hydride. Said active form of magnesium hydride was prepared by the reduction of dimethylmagnesium with LiAlH4 in diethyl ether. Thus the bulky dialkyl and alkylsubstituted cycloalkyl secondary amines are reacted with dimethylmagnesium to form the bis(dialkylamino)magnesium compounds which were in turn reacted in THF with the active form of magnesium hydride (see Ashbey, E. C., Goel, A. B., Lin, J. J. J. Or. Chem., 1978, 43, 1564. Such aminomagnesium hydrides are likely to initiate polymerization by the addition of amide to the monomer and result in undesired amine functionality in the resulting polymer distribution.
Michalczyk report the formation in ethereal or hydrocarbon solvents in the presence of "appropriate ligands" the formation of a precipitated form of magnesium hydride MgH2Lx. Such appropriate ligands included tetrahydrofuran, ethylene glycol dimethyl ether, and TMEDA. The reducing agent employed was phenylsilane (see Michalczyk, M. J. Organometallics, 1992, 11, 2307). In a recent review entitled "Molecular Early Main Group Metal Hydrides: Synthetic Challenge, Structures and Applications" Harder reviews the state of the art of the controlled synthesis of well-defined Group 1 and Group 2 metal hydrides. In general such hydrides have been prepared by the methods outlined above which include: photo-degradation; reactions of active hydrides to form "ate-complexes" such as the aryloxymagnesium hydride as well as the dialkylaminomagnesium hydrides reported by Ashby; Harder's [DIPPnacnacCaH.THF]2 initially formed from phenylsilane; and Stach's soluble lithium hydride complex formed from phenylsilane. Additionally Harder reviews a host of hydrides formed from the thermal decomposition of magnesite complexes [(iPr2N)3Mg−]M+(M+=Na+, K+). A common feature of all approaches to forming soluble saline hydride compositions is the use of bulky (usually isopropylated ligands) to achieve solubility. In all cases except for the poorly catalytic species formed during the hydrogenation of styrene to ethylbenzene (85% yield) such as the example using [DIPPnacnacCaH.THF]2 (which again was initially formed from phenylsilane) the saline hydride complexes were formed from some other reagent other than molecular hydrogen. Only Scheyer's insoluble forms of super active saline hydrides (SASH) are formed from molecular hydrogen and as the initial reagent.
Accordingly, the prior art does not disclose the use of either a highly active saline hydride (HASH) or a super active saline hydride (SASH) species for anionic-chain transfer polymerization of vinyl heteroaromatic monomers and/or vinyl aromatic monomers such as a styrenic monomers and/or conjugated diene monomers or other olefinic hydrocarbon anionically polymerizable monomers. The inventor has discovered that the use of these hydrides can catalyze a hydrogen mediated saline hydride initiated polymerization (HMSHIP) process. This invention provides a process for the efficient anionic chain transfer polymerization of vinyl aromatic monomers under ambient temperatures (e.g., about 20° C. to 100° C.) where hydrogen is the principal or sole chain transfer agent. Said process can be conducted at relatively low to very low hydrogen pressures partial pressures. Furthermore the inventor has discovered that the novel polymerization catalysts of this invention provide low molecular weight anionically polymerized styrene distributions comprised solely of styrene.

Process and catalyst for hydrogen mediated saline hydride initiated anionic chain transfer polymerization


A document editing hyphenating text words to obtain a more efficient use of the print material and provide a more aesthetically pleasing printed document. The apparatus has a keyboard for inputting text and including a hyphenation key. Also included in the apparatus are a display, a CPU, and a word dictionary that stores data of hyphenation positions of words. Once text is entered into a hot zone at the end of a line, the CPU executes line advance at the first space in the hot zone or the space preceding the word entered in the hot zone. When hyphenation is selected by the operator, based upon the displayed text, a cursor is moved to the left of a current line and the CPU calculates how many letters can be added to the right end of the preceding line. The CPU produces a display immediately above the word to the right of the cursor that indicates the number of letters that may be moved to the preceding line. The CPU also moves the cursor to an acceptable hyphenation position that is less than or equal to the number of letters that may be moved. The operator may accept the CPU designated hyphenation position or move the cursor to another position within the word for hyphenation. The operator designated hyphenation position may not be greater than the number of letters that may be moved to the preceding line.

1. Field of the Invention
The present invention relates to a document editing apparatus which performs automatic line advancement in response to a key entry made at a character position near the end of a text line, and particularly to a document editing apparatus capable of splitting a word into segments and placing the word segments at the tail of the first line and the head of the second line of two consecutive text lines.
2. Description of Related Art
A conventional document editing apparatus operative to split a displayed character string, i.e., a word, into segments and display the word segments continuously on two text lines based on the operator's response is disclosed in Japanese Patent Laid-open No. 63-20661, for example. This technique is designed to evaluate the size of a blank portion at the line end, which would be created if space characters used between words on the text line were reduced in size and the text line were left justified, and display the number of characters, which can be moved to the created blank portion, at the top of the next line. The operator is informed of the maximum number of characters, out of the leading word on the next line, which can be moved to the blank portion of the preceding line, so that the operator knows the range of possible word split positions for the leading word on the next line.
In general, when a word is split into two segments displayed on two consecutive lines, a hyphen is attached to the end of the former segment to indicate that the two segments form a complete word. The word split position, i.e., the position of hyphenation, is not arbitrary, as each word has legitimate split position(s) depending on syllables and meaning of the word.
The conventional document editing apparatus, however, merely displays the number of characters which can be moved to the preceding text line, and therefore the operator is obliged to determine the best position of word segmentation and hyphenation in moving a word segment to the preceding text line on each occasion. For this reason, a wrong word split position can possibly be selected and considerable time expended before the operator chooses or determines a proper word split position.
The "IBM Technical Disclosure Bulletin", Vol.29, No.1, pp.383-384, published in June 1986, describes the function of hyphenation based on a dictionary. However, this hyphening function simply inserts a hyphen in a word in accordance with the dictionary, and it sets a hyphening position without any consideration of the number of characters of the word and the number of characters which can be placed at the end of the preceding text line. Accordingly, the operator must decide on hyphenation through the assessment of the matching between the number of characters of the former word segment and the number of characters which can stay at the end of the preceding text line by counting the characters. Consequently, the operator spends a lot of time selecting the proper hyphening position.

Automatic hyphenation apparatus displaying grammatically correct suggestions for hyphenation of a word isolated on a single display line


Systems and methodologies for generating a bridge file linking a subject identifier (Subject ID) (or a tokenized subject identifier), used to anonymize a subject in a trial, to tokenized personal identification information (PII), used to de-identify other data for the subject, without revealing the link between the subject identifier (subject ID) and the personal identifying information (PII) for the subject. The bridge file can then be used to link trial data for the subject anonymized with a subject ID to other data for the subject de-identified with tokenized PII.

Generally, regulations and laws protecting the privacy of personal data have created a plethora of strategies for protecting the identity of personal data. For example, it is a potential Health Insurance Portability and Accountability Act (HIPAA) violation to incorporate personal health information (PHI) elements into a healthcare data set. Accordingly, to be compliant with government regulations, all PHI data elements must be removed and/or de-identified before being incorporated into any healthcare data set. Typically, institutions, organizations, and businesses that create personal data have their own methods for complying with identity protection laws. These methods may include in-house developed proprietary methods, or one of many disparate off-the-shelf solutions. The conventional methods utilized for protecting personal data have been responsible for serious identity breaches resulting in the theft of customer and employee personal information. Conventional methods implement processes of de-identification by the use of hashing methods applied to strings of characters generated from private data elements in data records. These conventional processes are built using a single hashing seed or encryption key, which is shared across many disparate target sites. Such systems suffer the risk that the resulting generated values can be mapped back to the original source data. Once a breach has occurred, all the target data sites have exposed values which, in themselves, could become regulated data values. Conventional processes also create problems because once PHI data elements are removed from record, users have no way to understand which individuals in the data set match the de-identified individuals, and so conventional healthcare data systems are limited in their ability to identify the existence of duplicate records or duplicate individuals from individual de-identified records in healthcare data sets.
Additionally, the personal data records stored by the various entities cannot be shared or aggregated for any meaningful or useful data analysis. Specifically, the personal data cannot be shared between entities where the identity any one particular individual is of no importance. A problem associated with protected personal data is easily recognizable in the industries related to healthcare where each provider or insurer typically employs their own proprietary methods for de-identifying personal data records, making it nearly impossible to do any meaningful aggregations of the data for important clinical research or cost analysis at higher regional, state, or national levels. This problem is compounded by the fact that there are many separate and distinct companies involved with the care of an individual patient, making it difficult to share and or tie the information together for a single patient once the stake holder has applied their own proprietary de-identification process to the patient's personal data records.
Standardized solutions, such as Datavant's de-dentification and linking solutions have been developed to address these issues. However, even with a standardized way of de-identifying and linking data based on tokenizing the personal identifying information (PII) of the individual associated with the data, trials, such as clinical trials, provide additional issues. Typically, each participant in a trial is identified with a subject identifier (Subject ID) rather than their personal identifying information (PII) to maintain anonymity. For example, the subject named "John Smith" might be identified as "Subject 12" for the purposes of the data collected and presented in the trial. This additional layer of abstraction means that data for a subject from the trial cannot be easily linked to other data for the subject that has been de-identified in conventional manner by tokenizing the personal identification information (PII) associated with the data. Since the subject in the trial is identified by a subject ID, there is no personal identification information (PII) associated with the trial data to be encrypted and linked to other data using such standardized solutions. While the trial site might collect the subject's PII when setting up the trial, the PII never leaves the trial site. The trial originator or sponsor or other entities interested in the data only get the subject ID identification associated with the trial data.

This patent is subject to a terminal disclaimer.

Linking of tokenized trial data to other tokenized data


A fuel injection pump for internal combustion engines having in-line cylinder bushes, in each of which a pump piston defining a pump work chamber is guided, the piston being rotatable by a governor rod for the sake of fuel supply quantity regulation. Mounted on the pump housing is an adjusting device, in which an adjusting piston is guided axially parallel with the governor rod; the adjusting piston has a radial pin, which protrudes through a slit in the wall of the adjusting device and pump housing into an oblong slot of the governor rod, thus limiting the adjusting motion of the rod in certain operating ranges. The position of the adjusting piston determines the maximum governing travel of the governor rod in the full-load direction upon engine starting. The adjusting piston is variable via an adjustable stop acting upon one face end thereof and is also variable as a function of temperature via a temperature-dependent spring element disposed on its circumference. In addition, with its face end, the adjusting piston defines a pressure chamber, by way of which the adjusting piston can be adjusted pneumatically in the direction of a zero supply quantity; via two stops of the oblong slot, the adjusting piston moves the control rod with it in the process and in this way interrupts the fuel delivery.

The invention is based on a fuel injection pump for internal combustion engines as defined hereinafter. In a fuel injection pump of the type disclosed in German Patent 26 46 546, which is the same as U.S. Pat. No. 4,208,998, an adjusting device is mounted on the pump housing, an adjusting piston is longitudinally displaceably adjustable in this adjusting device, parallel to the axis of the governor rod of the fuel injection pump, by a pressure medium counter to the force of a restoring spring, and the adjusting piston has a radially protruding intermediate member that via a windowlike recess in the pump housing engages an oblong slot of the governor rod. The axial boundary edges of the oblong slot in the direction of governor rod motion, in cooperation with the intermediate member, form one stop each in the directions of the full-load and zero supply quantities, the stops corresponding to stop positions and becoming operative only when the adjusting piston has been displaced. The motion of the adjusting piston tripped by the pressure medium serves to adjust it in the direction of a zero supply quantity, and the intermediate member comes to rest on the boundary edge of the governor rod; as the adjusting motion continues, counter to the force of a drag member on the governor, the adjusting piston displaces the governor rod as far as a stop position. The known adjusting device is used in this way primarily to turn off the engine; via a support forming a stop of the adjusting piston in the event of pressure relief, the maximum supply quantity position is also adjustable via the adjusting device, especially when the engine is started. For that purpose, it is possible to embody this stop adjustably and to control this adjustment as a function of engine operating parameters, such as temperature. However, if it is intended that the known adjusting device not only perform the shutoff function but also provide an adjustable starting quantity and independently thereof a temperature-dependent starting quantity control as well, then additional components are required, and they must be mounted on the housing of the adjusting device, which means that they take up additional space.

Fuel injection pump for internal combustion engines


A system, method, and computer program are provided for using speech recognition to assist call center interactions with a caller. In operation, utterances are received between a caller and an agent. Additionally, speech recognition is performed on the utterances utilizing a context of the utterances. Furthermore, an interaction with the caller is assisted utilizing the speech recognition.

Customer interaction is an important aspect for every business providing a product or a service. Developing and maintaining efficient mechanisms for customer interaction is desirable. For example, it is desirable to implement efficient and reliable mechanisms for customer interactions involving phone communications, as these communications make up a large number of interactions with customers. There is thus a need for addressing these and/or other issues.

System, method, and computer program for speech recognition assisted call center and self service interface


Mixed micelles containing poly(L-histidine)-poly(ethylene glycol) block copolymer and poly(L-lactic acid)-poly(ethylene glycol) block copolymer are a pH-sensitive drug carrier that release the drug in an acidic microenvironment, but not in the blood. Since the microenvironment of solid tumors is acidic, these mixed micelles are useful for treating cancer, including those cancers exhibiting multidrug resistance. Targeting ligands, such as folate, can also be attached to the mixed micelles for enhancing drug delivery into cells. Methods of making poly(L-histidine), synthetic intermediates, and block copolymers are also described.

This invention relates to drug delivery. More particularly, this invention relates to polymeric micelles for targeted drug delivery, including drug delivery for treating cancer and bypassing multidrug resistance of cancer cells by taking advantage of tumor pH.
Although important findings in scientific research and technological advances, such as long-circulating carriers, enhanced permeation and retention (EPR) effect, and receptor-mediated endocytosis, have been achieved in the last decades for effective solid tumor targeting, chemotherapy still faces a major challenge for improving specific drug accumulation in tumor sites. Z. Ning et al., Increased microvascular permeability contributes to preferential accumulation of stealth liposomes in tumor tissue, 53 Cancer Res. 3764–3770 (1993); S. M. Moghimi et al., Long-circulating and target-specific nanoparticles: Theory and practice, 53 Pharmacol. Rev. 283–318 (2001); D. Putnam & J. Kopecek, Polymer conjugates with anticancer activity, 122 Adv. Polymer. Sci. 57–123 (1995); D. C. Drummond et al., Optimizing liposomes for delivery of chemotherapeutic agents to solid tumors, 51 Pharmcol. Rev. 691–743 (1999); M. Yokoyama, Novel passive targetable drug delivery with polymeric micelles, in Biorelated Polymers and Gels 193–229 (T. Okano ed. 1998).
The tumor extracellular pH (pHe) is a consistently distinguishing phenotype of most solid tumors from surrounding normal tissues. The measured pH values of most solid tumors in patients, using invasive microelectrodes, range from pH 5.7 to pH 7.8 with a mean value of 7.0. More than 80% of these measured values are below pH 7.2, while normal blood pH remains constant at pH 7.4. K. Engin et al., Extracellular pH distribution in human tumors, 11 Int. J. Hyperthermia 211–216 (1995); R. van Sluis et al., In vivo imaging of extracellular pH using 1H MRSI, 41 Magn. Reson. Med. 743–750 (1999); A. S. E. Ojugo et al., Measurement of the extracellular pH of solid tumors in mice by magnetic resonance spectroscopy: a comparison of exogenous 19F and 31P probes, 12 NMR Biomed. 495–504 (1999). The acidity of tumor interstitial fluid is mainly attributed, if not entirely, to the higher rate of aerobic and anaerobic glycolysis in cancer cells (proton production by lactate formation and ATP lysis) than normal cells. M. Stubbs et al., Causes and consequences of tumour acidity and implications for treatment, 6 Opinion 15–19 (2000). Such acidic extracellular pH has prompted researchers to attempt to establish pH-sensitive anticancer drug delivery systems, such as pH-sensitive liposomes. However, effective systems have not been achieved because of lack of proper pH-sensitive functional groups in the physiological pH range. O. V. Gerasimov et al., Cytosolic drug delivery using pH- and light-sensitive liposomes, 38 Adv. Drug Deliv. Rev. 317–338 (1999); O. Meyer et al., Copolymers of N-isopropylacrylamide can trigger pH sensitivity to stable liposomes, 421 FEBS Lett. 61–64 (1998). Recently, water soluble polymers modified with sulfonamide self-assembled nanoparticles showed enhanced drug release, interaction with and internalization into cells at tumor pH. K. Na & Y. H. Bae, Self-assembled hydrogel nanoparticles responsive to tumor extracellular pH from pullulan derivative/sulfonamide conjugate: Characterization, aggregation and adriamycin release in vitro, 19 Pharm. Res. 681–688 (2002); S. K. Han, K. Na & Y. H. Bae, Sulfonamide based pH-sensitive polymeric micelles: physicochemical characteristics and pH-dependent aggregation, Colloids. Surf. A. Physicochem. Eng. Aspects 00 1–11 (2002); K. Na, E. S. Lee & Y. H Bae, Adriamycin loaded pullulan acetate/sulfonamide conjugate nanoparticles responding to tumor pH: pH-dependent cell interaction, internalization and cytotoxicity in vitro, J. Contr. Release (in press).
In view of the foregoing, it will be appreciated that providing a pH-dependent drug carrier that releases a drug in the acidic microenvironment of solid tumors while maintaining stability in the blood would be a significant advancement in the art.

pH-sensitive polymeric micelles for drug delivery


A process for the enzymatic hydrolysis of cellulose to produce a hydrolysis product from a pre-treated cellulosic feedstock is provided. The process comprises introducing an aqueous slurry of the pre-treated cellulosic feedstock at the bottom of a hydrolysis reactor. Axial dispersion in the reactor is limited by avoiding mixing and maintaining an average slurry flow velocity of about 0.1 to about 20 feet per hour, such that the undissolved solids flow upward at a rate slower than that of the liquid. Cellulase enzymes are added to the aqueous slurry before or during the step of introducing. An aqueous stream comprising hydrolysis product and unhydrolyzed solids is removed from the hydrolysis reactor. Also provided are enzyme compositions which comprise cellulase enzymes and flocculents for use in the process. In addition, a kit comprising cellulase enzymes and flocculent is provided.

Fuel ethanol is currently produced from feedstocks such as cornstarch, sugar cane, and sugar beets. However, the production of ethanol from these sources cannot expand much further due to limited farmland suitable for the production of such crops and competing interests with the human and animal food chain. Finally, the use of fossil fuels, with the associated release of carbon dioxide and other products, in the conversion process is a negative environmental impact of the use of these feedstocks
The possibility of producing ethanol from cellulose-containing feedstocks such as agricultural wastes, grasses, and forestry wastes has received much attention due to the availability of large amounts of these inexpensive feedstocks, the desirability to avoid burning or landfilling cellulosic waste materials, and the cleanliness of ethanol as a fuel compared to gasoline. In addition, a byproduct of the cellulose conversion process, lignin, can be used as a fuel to power the cellulose conversion process, thereby avoiding the use of fossil fuels. Studies have shown that, taking the entire cycle into account, the use of ethanol produced from cellulose generates close to nil greenhouse gases.
The cellulosic feedstocks that may be used for ethanol production include (1) agricultural wastes such as corn stover, wheat straw, barley straw, oat straw, oat hulls, canola straw, and soybean stover; (2) grasses such as switch grass, miscanthus, cord grass, and reed canary grass; (3) forestry wastes such as aspen wood and sawdust; and (4) sugar processing residues such as bagasse and beet pulp.
Cellulose consists of a crystalline structure that is very resistant to breakdown, as is hemicellulose, the second most prevalent component of cellulosic feedstocks. The conversion of cellulosic fibers to ethanol requires: 1) liberating cellulose and hemicellulose from lignin or increasing the accessibility of cellulose and hemicellulose within the cellulosic feedstock to cellulase enzymes, 2) depolymerizing hemicellulose and cellulose carbohydrate polymers to free sugars, and 3) fermenting the mixed hexose and pentose sugars to ethanol.
Among well-known methods used to convert cellulose to sugars is an acid hydrolysis process involving the use of steam and acid at a temperature, acid concentration and length of time sufficient to hydrolyze the cellulose to glucose (Grethlein, 1978, J. Appl. Chem. Biotechnol. 28:296-308). The glucose is then fermented to ethanol using yeast, and the ethanol is recovered and purified by distillation.
An alternative method of cellulose hydrolysis is an acid prehydrolysis (or pre-treatment) followed by enzymatic hydrolysis. In this sequence, the cellulosic material is first pre-treated using the acid hydrolysis process described above, but at milder temperatures, acid concentration and treatment time. This pre-treatment process increases the accessibility of cellulose within the cellulosic fibers for subsequent enzymatic conversion steps, but results in little conversion of the cellulose to glucose itself. In the next step, the pre-treated feedstock is adjusted to an appropriate temperature and pH, then submitted to enzymatic conversion by cellulase enzymes.
The hydrolysis of the cellulose, whether by acid or by cellulase enzymes, is followed by the fermentation of the sugar to ethanol, which is then recovered by distillation.
The efficient conversion of cellulose from cellulosic material into sugars, and the subsequent fermentation of sugars to ethanol, is faced with a major challenge regarding commercial viability. In particular, acid prehydrolysis requires large amounts of acid. For a clean feedstock, such as washed hardwood, the sulfuric acid demand is 0.5% to 1% of the dry weight of the feedstock; for agricultural fibers, which can contain high levels of silica, salts, and alkali potassium compounds from the soil, the acid demand can be up to about 10-fold higher, reaching 5% to 7% by weight of feedstock. This adds significant cost to the process. A second drawback of using large amounts of acids in a prehydrolysis process is that the acidified feedstock must be neutralized to a pH between about 4.5 and about 5 prior to enzymatic hydrolysis with cellulase enzyme. The amount of caustic soda used to neutralize acidified feedstock is proportional to the amount of acid used to acidify the feedstock. Thus, high acid usage results in high caustic soda usage, which further increases the cost of processing cellulosic feedstock to ethanol. Furthermore, the cost of enzymatic hydrolysis is high, as cellulose remains resistant to hydrolysis despite pre-treatment, which increases the enzyme dosage required. Such increased requirement can be counteracted by increasing the hydrolysis times (90-200 hours), in turn requiring very large reactors, which again adds to the overall cost.
A method of decreasing the enzyme dosage while maintaining high levels of cellulose conversion is Simultaneous Saccharification and Fermentation (SSF). In this type of system, enzymatic hydrolysis is carried out concurrently with yeast fermentation of glucose to ethanol in a reactor vessel. During SSF, the yeast removes glucose from the reactor by fermenting it to ethanol and this decreases inhibition of the cellulase by glucose. However, the cellulase enzymes are still inhibited by ethanol. SSF is typically carried out at temperatures of 35-38° C., which is a compromise between the 50° C. optimum for cellulase and the 28° C. optimum for yeast. This intermediate temperature leads to substandard performance by both the cellulase enzymes and the yeast. Thus, the inefficient catalysis requires very long reaction times and very large reaction vessels—both of which are costly.
A method for higher volumetric productivity is disclosed in U.S. Pat. No. 5,258,293 (Lynd). This method utilizes a lignocellulosic feedstock along with microorganisms that are continuously introduced into a reaction vessel. Fluid is also continuously added from the bottom of the reaction vessel, but no mechanical agitation of the slurry occurs. As the reaction progresses, the lignocellulosic feedstock being digested tends to accumulate in a spatially non-homogenous layer while the ethanol product rises to a top layer, where it is removed. The insoluble substrate accumulates in a bottom layer and can be withdrawn from the vessel. This arrangement results in a differential retention of the fermenting substrate, which allows for increased residence time in the reactor vessel.
In another approach, disclosed in U.S. Pat. No. 5,837,506 (Lynd), ethanol is produced using an intermittently agitated, perpetually fed bioreactor. Lignocellulosic slurry and microorganisms are added to a reactor; the mixture is then agitated, either by mechanical means or by fluid recirculation, for a specific time interval, after which it is allowed to settle. Ethanol is then removed from a top portion of the reactor, additional substrate is added, and the cycle continues. In a similar method, Kleijntjens et al. (1986, Biotechnology Letters, 8:667-672) utilize an upflow reactor to ferment cellulose-containing substrate in the presence of C. thermocellum. The substrate slurry settles to form an aggregated fibre bed, which is accelerated by slow mechanical stirring. Substrate is added periodically, while liquid is continuously fed to the reactor. Ethanol product accumulates in a top layer, where it is removed from the reactor. The methods disclosed in U.S. Pat. No. 5,837,506, U.S. Pat. No. 5,258,293 and Kleijntjens et al. result in an increase in the residence time of the feedstock in the reactor vessel. However, all three methods suffer from the disadvantages of the SSF process.
U.S. Pat. No. 5,348,871; U.S. Pat. No. 5,508,183; U.S. Pat. No. 5,248,484; and U.S. Pat. No. 5,637,502 (Scott) teach a method to improve the conversion efficiency in enzymatic hydrolysis through the use of an attritor in association with an agitated reactor vessel. The agitator produces a high-shear field for size reduction of solid particles in the cellulosic feedstock, which constantly provides new surface area for the cellulase enzymes. Therefore, the reaction efficiency is increased and the enzyme requirements are decreased. However, the high shear often inactivates the enzymes. Furthermore, the cost of the attritor equipment is much greater than the savings due to the decreased enzyme dosage.
U.S. Pat. No. 5,888,806 and U.S. Pat. No. 5,733,758 (Nguyen) teach an alternative approach using a tower hydrolysis reactor comprising alternating mixed and unmixed zones, thus reducing the mixing power consumption and cost. The slurry is moved upward in plug flow through the reactor and is intermittently mixed in the mixing zones, thus preventing channeling of liquid and ensuring uniform heat and mass transfer. While the methods disclosed in U.S. Pat. No. 5,888,806 and U.S. Pat. No. 5,733,758 reduce the shearing and denaturation of the enzymes, the cost of the mixing equipment is substantial. Furthermore, the kinetic performance of the enzymes is no better than can be achieved in a batch hydrolysis mode.
At present there is much difficulty in the art to attain high conversion efficiency while maintaining lowered costs. Increasing hydrolysis times to avoid higher costs of increasing the enzyme dosage requires larger reactors, which in turn increases equipment costs. Mixing and intermittent mixing of the feedstock during hydrolysis can increase enzyme efficiency but equipment costs will again increase, and shear forces will cause enzyme denaturation. Other systems compromise the optimal enzyme activity and reduce the efficiency of the enzymes.

Upflow reactor for enzymatic hydrolysis of cellulose


A Class D amplifier includes a tracking circuit and a regulation circuit to provide efficient, accurate protection against excessive current flow in the power FET's of the amplifier output stage. The FET currents flowing in the output stage are mirrored across tracking resistors by the tracking circuit. The resultant voltage drops are compared to reference voltages to detect over-current situations. By mirroring scaled-down versions of the output currents, power consumption in the tracking circuit is minimized. When an over-current situation is detected, the regulation circuit modulates the duty cycle of the signal input to the output stage until the FET currents fall to acceptable levels. If two over-current indications occur during a single clocking cycle of the pulse-width modulator of the amplifier, the regulation circuit shuts off the amplifier to protect against short-circuit damage.

1. Field of the Invention
The present invention relates to Class D electronic amplifiers, and in particular, to amplifier output stage over-current protection circuits.
2. Discussion of the Related Art
In a Class D amplifier, a pulse-width modulator (PWM) converts an incoming signal into a high-frequency rectangular wave, the average value of which tracks the incoming signal magnitude. This rectangular wave is fed to a set of power FET's, which provide an output signal that is filtered and then used to drive an external speaker. As shown in FIG. 1, a signal ANALOG.sub.-- IN is received by a pulse-width modulator, or PWM 101. PWM 101 generates a signal PWM.sub.-- OUT, which is a rectangular wave of a frequency defined by a PWM clock CK101. Signal PWM.sub.-- OUT is then split and fed through level shifter/line driver circuits 103, 104, 105 and 106, to FET's Q107, Q108, Q109 and Q110, respectively, which make up an FET output bridge 121. An inductor L117, a capacitor C119, and an inductor L118 provide output filtering that averages the digital output of the output bridge and provides an analog driving signal across external speaker 120. Speaker 120 can be a single speaker or a set of speakers. When signal PWM.sub.-- OUT is in a HIGH state, circuit 103 activates FET Q107 and circuit 104 activates FET Q110. At the same time, because an inverter 102 inverts signal PWM.sub.-- OUT as it is going to circuits 104 and 105, FET's Q108 and Q109 are turned off. As a result, current flows from FET Q107 to FET Q110, through speaker 120. When signal PWM.sub.-- OUT switches to a LOW state, FET's Q107 and Q110 are turned off, and FET's Q108 and Q109 are activated. Now current flows through speaker 120 in the opposite direction, from FET Q109 to FET Q108. This alternating current flow drives the voice coil in speaker 120, reproducing the original input signal ANALOG.sub.-- IN as an audio output.
In the FET output bridge of a conventional Class D amplifier, the individual FET's have a limited current sourcing capacity. A short at the FET bridge outputs or an overly large input signal can place excessive current demands on the FET's, leading to possible damage to both the amplifier and the external load. A typical defense against this scenario is to use protective fuses, as illustrated by fuses F111 and F112 in FIG. 1. An over-current situation in FET Q107 would cause fuse F111 to blow before any major damage to the amplifier could occur, while an over-current in FET Q108 would break the link in fuse F112. In either case, however, the blown fuse would have to be replaced before the amplifier would regain functionality. Therefore, although this method provides positive protection against overload, recovery from an over-current incident is cumbersome. A second over-current protection scheme used in conventional Class D amplifiers alleviates some of the inconvenience associated with fuses. Instead of a fuse, a small resistor is placed in series with each FET. The voltage drop across the resistor is monitored, and the amplifier is shut down when the voltage drop exceeds a predefined limit. This implementation is depicted in FIG. 1 by resistors R113 and R114. Comparator circuits 115 and 116 monitor the voltage drops across resistors R113 and R114, respectively, and generate a signal SHUT.sub.-- DOWN to turn off power to the amplifier when a threshold voltage limit is passed. While this method provides a more precise over-current setpoint and easier recovery from over-current situations, the resistor in the signal path increases power consumption during normal operation, decreasing overall amplifier efficiency. In addition, both of the described methods are a less-than-optimal solution to the scenario in which the excessive currents are caused by a large incoming signal. While a short-circuit definitely requires some sort of immediate examination, a large incoming signal may only be temporary, and is not necessarily indicative of a severe problem. However, conventional protection schemes preclude continuous amplifier output when any over-current situation arises.
Accordingly, it is desirable to provide an over-current protection circuit that consumes low quiescent power and maximizes amplifier output while still preventing damage from short-circuit situations.

Short-circuit protection and over-current modulation to maximize audio amplifier output power


Optical parts and optical equipment, including lenses, mirrors and laser media made of athermal glasses having compositions comprising 0-13 mol % CdO, 9-24 mol % CdF.sub.2, 5-10 mol % LiF, 30-34.5 mol % AlF.sub.3 28-33.5 mol % PbF.sub.2, 0-4 mol % KF, 0-6.5 mol % YF.sub.3, and 0-2 mol % LaF.sub.3 and having little or no optical path length change as a function of temperature in the infrared region of 1.mu.m to 5.mu.m.

The present invention is related to glasses for infrared applications, especially infrared athermal fluoride glasses whose optical path length change as a function of temperature change will become practically zero especially in the infrared region of 1 to 5.5 .mu.m, and optical parts as well as optical equipment utilizing these glasses.
In performing precise optical measurements, generally, the problem is that there is an optical system variation due to temperature change. As a typical example, the optical system may comprise a camera, especially camera lenses, for example, on board a space satellite, where a large temperature difference will occur between the portion irradiated by the sun light and the shaded portion. When a temperature difference occurs in a lens, it will appear as heterogeneity in refractive index and cause disorder in the image, and it MAY detrimentally affect the resolution capability of the camera--this has been observed in the past. Generally, the refractive indices of oxide system glasses rise with the rise in temperature. The temperature coefficient of refractive index, dn/dT is of the order of +10 to +2.times.10.sup.-6 /.degree. C. (Tryggve Baak, J. Opt. Soc. Am., 59 (1969) 851).
In conjunction with the refractive index change, there is a linear expansion coefficient problem which will appear as a thickness change in the optical system. Although the linear expansion coefficient of quartz (silica) is very small, 5.times.10.sup.-7 /.degree. C., it exhibits a large dn/dT value of +10.times.10.sup.-6 /.degree. C. Because of this, attempts have been made to find a special oxide glass system to make the temperature coefficient of the refractive index, dn/dT, zero, and to account for both the refractive index temperature change and expansion. The development of athermal glass, whose optical path length temperature change, ds/dT, is zero, has been attempted by developing special oxide glasses (F. Reitmayer and H. Schroeder, Appl. Opt., 14 (1975) 716). However, these are based on interference methods utilizing a visible laser light; thus they are athermal glasses in the visible region. So far no report has been published on athermal glasses at wavelengths longer than 1 .mu.m, which would be important for infrared cameras, etc.
Of course, the infrared transparency of metal fluoride glasses has long been recognized, and efforts have been made to develop stable fluoride glasses to exploit this transparency. U.S. Pat. Nos. 4,537,864 and 4,752,593, for example, report stabilized Cd--Li--A1--Pb--F glasses with excellent transparency in the 2-6 micron wavelength range.
Little attention has been given, however, to the thermal properties of halide glasses in the infrared regime. Thus the values of dn/dT and ds/dT of fluoride glasses, have been reported only for ZrF.sub.4 system glasses. These values of dn/dT and ds/dT.sub.abs are, respectively, -11.times.10.sup.-6 /.degree. C. and -2.2.times.10.sup.-6 /.degree. C. (for ZrF.sub.4 --BaF.sub.2 --GdF.sub.3 --AlF.sub.3); and for the AlF.sub.3 system glass example, dn/dT and ds/dT.sub.abs are -6.7.times.10.sup.-6 /.degree. C. and Technology, Vol. 7, No. 8 (1989) p. 1256. These numbers do not suggest that fluoride glasses would be superior infrared athermal glasses, consequently, no report has been published on optical systems and optical parts constructed of athermal glasses operating in the infrared region.
Furthermore, athermal glasses are effective as laser media where the laser medium refractive index temperature change due to heat generation during laser oscillation and the optical path length change present problems for the stability of the laser oscillation mode. In recent years, oxide glasses and fluoride glasses are being developed as media for Er, Nd, etc. lasers which oscillate at wavelengths longer than 1 .mu.m; however, presently, there has been no use of athermal glass as a laser medium at wavelength longer than 1 .mu.m.
As described above, the realization of infrared athermal glasses which will not generate optical path length difference in the infrared region and the realization of optical parts and optical equipment utilizing these glasses are strongly desired.
The objective of the present invention is to provide new glass compositions which do not change optical path length as a function of temperature change in the 1-5.5 .mu.m band. Furthermore, by using these glasses as lens or laser media for incorporation into optical parts, it is an aspect of the present invention to provide infrared optical equipment or optical parts which will not suffer degraded resolution capability due to temperature change in the infrared region and which will not increase in instability during laser performance.

Optical parts and equipment using infrared athermal glasses


A magnetic head supporting mechanism includes a head positioning actuator having an arm, and a load beam connected to the arm. The load beam has a gimbal. The gimbal includes a magnetic head slider fixing portion on which a magnetic head slider having a magnetic head is mounted, a first pair of beams extending from opposite sides of the magnetic head slider fixing portion along a traverse direction of the load beam perpendicular to a longitudinal direction thereof, and a second pair of beams respectively connected to the first pair of beams and extending so as to face the opposite sides of the magnetic head slider fixing portion.

1. Field of the Invention
The present invention relates to a magnetic head supporting mechanism used for a magnetic disk drive.
2. Description of the Related Art
A magnetic head slider on which a magnetic head is mounted is attached to a free end of a load beam, and is maintained, during a recording/reproducing operation, in a state in which the magnetic head slider flies above a magnetic disk.
Recently, it has been required to improve an HDI (Head Disk Interface) characteristic, which is one of the parameters describing the reliability of magnetic disk drives. In order to meet the above requirement, it is necessary to diminish the mass of the magnetic head slider or reduce a spring force urging the magnetic head slider towards the magnetic disk.
The following event will occur when the magnetic head slider is diminished. It is necessary to reduce the size of a supporting spring which holds the magnetic head slider as the slider is reduced in size. This is intended to maintain the following characteristic with respect to waviness of the disk and maintain the flying stability of the head. The following event will occur when the spring force on the head slider is reduced. That is, the flying stiffness of the head is degraded due to reduction of the spring force on the head slider. Further, the possibility of assembly errors increases because parts, such as a slider and a supporting spring, are diminished in mass. With the above in mind, it is necessary for a device for supporting a magnetic head slider to have a mechanism capable of sufficiently ensuring the flying stability of the magnetic head slider.
Conventionally, the magnetic head supporting mechanism is made up of a load beam, a gimbal fixed to the load beam, and a magnetic head slider fixed to the gimbal. With the above structure, it is more difficult to assemble (position) these parts as the size of the parts is reduced. When there is an assembly error, the magnetic head slider is maintained in an unbalance flying state in which the slider flies in a tilted state. Hence, the reliability of the flying head is degraded and further the read/write characteristics are also degraded. As a result, the reliability of the magnetic disk drive is also degraded.
In order to eliminate the factors causing the unbalanced flying due to the assembly error of the head supporting mechanism, Japanese Patent Laid-Open Application No. 3-189976 proposes an improvement in which an integrally formed supporting spring corresponding to the conventional load beam and gimbal is used and assembly is no longer needed.
FIG. 1 shows a magnetic head supporting mechanism 1 disclosed in the above application document. The magnetic head supporting mechanism 1 includes a load arm 3 and a load beam 4 (which is also referred to as a flexure). The load beam 4 includes a gimbal 5, which has openings (through holes) 6 and 7 having a substantially C shape. Further, the gimbal 5 includes a beam 8 supported at both ends in a direction in which the beam 8 traverses the load beam 4, and tongue portions 9 and 10 extending from the beam 8. The back surface of the magnetic head slider 11 is formed so that grooves are formed in the width direction of the load beam 4.
The magnetic head slider 11 can be rotated together with a twist of the beam 8 in a pitching direction indicated by an arrow 12, and can be rotated together with a bend of the beam 8 in a rolling direction indicated by an arrow 13.
It is necessary to reduce the rotation stiffness of the gimbal 5 in order to ensure the flying stability of the compact magnetic head slider. Further, it is impossible to reduce the thickness t of the gimbal 5 having the above structure because the load beam 4 needs to be stiff. In order to reduce the rotation stiffness of the gimbal 5 without reducing the thickness t of the load beam 4, it is necessary to lengthen the length l of the beam 8. If the load beam 4 and the gimbal 5 are made to have different thicknesses, it is necessary to a complex process in which only the gimbal 5 is half etched, while the load beam is not processed. However, it is very difficult to obtain a desired precision in thickness by the above process and to obtain desirable characteristics.
If the length 1 of the beam 8 is increased, the following disadvantages will occur. First, the resonance point (frequency) of vibration of the twist and bend of the beam 8 becomes lower, and it becomes likely that the degree of flying of the magnetic head slider 11 is varied. Second, the width W of the load beam 4 increases, and hence the resonance frequency of vibration of the load beam 4 itself will becomes lower. Thus, the flying magnetic head slider 11 becomes unstable.
Consequently, when the integrally formed supporting spring having the integrated load beam and gimbal is used, it is very difficult to realize a structure of the integrated supporting spring in which only the rotation stiffness is reduced without decreasing the resonance frequency of the gimbal.
It becomes impossible to neglect the influence of lead wires connected to the head because of degradation of the air bearing stiffness caused by down-sizing of the slider and reduction in the load force on the head slider. More particularly, the slider is affected by the stiffness of the lead wires and may cause the slider to fly in the tilt state. Particularly, when a magneto-resistive effect type head (MR head) is used as a reproduction head, such a head is combined with an interactive type head. Hence, four lead wires equal to twice the number of lead wires for the conventional recording/reproducing head are needed. Use of the four lead wires increases the influence of the stiffness of the lead wires. This degrades not only the reliability of the flying head but also the read/write characteristics. Hence, the magnetic disk drive does not have satisfactory reliability.


The subject matter described herein relates generally to compositions and formulations and methods of use of combinations of pyroglutamic acid and a strobilurin fungicide for improving plant growth, health and yields, and for protecting plants against selected stress conditions.

The use of agrochemicals has greatly enhanced agricultural productivity and yields. Rapid plant growth is desirable as it is an important factor in timing, harvesting and cost of production. As such, rapid plant growth and yield maximization are economically important goals for many agricultural businesses that grow high-value crops.
Though productivity has increased, it has become apparent that there are limits to the amount of agrochemicals that can be added to plants and that can be safely absorbed into the environment. With increased demands on agricultural productivity comes environmental and economic requirements. This is particularly true with regard to the use of agrochemicals during production because of cost and safety. Efficiency of agrochemicals is important because of the associated costs, and the possible impact of agrochemicals on the environment and the health of humans and animals. There is a desire for reduction of the amount of agrochemicals applied; yet, the need for ever-increasing production remains.
What is therefore needed and addressed by the subject matter described herein is an improvement in plant growth, health and yields.

Combination of pyroglutamic acid and a strobilurin fungicide for improved plant health effects


Disclosed herein, among other things, is a method performed by a user equipment (UE) for providing to a network channel station information (CSI). The method comprises: receiving from the network two measurement power offsets, a first measurement power offset and a second measurement power offset; selecting one of said two measurement power offsets; computing CSI using the selected measurement power offset; and transmitting to the network the determined CSI.

Multiple input multiple output (MIMO) is an advanced antenna technique to improve the spectral efficiency and thereby boosting the overall system capacity. The MIMO technique uses a commonly known notation (M×N) to represent MIMO configuration in terms number of transmit (M) and receive antennas (N). The common MIMO configurations used or currently discussed for various technologies are: (2×1), (1×2), (2×2), (4×2), (8×2) and (8×4). The configurations represented by (2×1) and (1×2) are special cases of MIMO and they correspond to transmit diversity and receiver diversity respectively. The configuration (2×2) is used in WCDMA release 7 and configurations ((4×4), (4×2) (4×1)) are being defined in Third Generation Partnership Project (3GPP) release 11.
Currently a 4Tx transmissions scheme for High-Speed Downlink Packet Access (HSDPA) is discussed within 3GPP standardization. Previous versions of the specification supported up to 2 TX antenna transmissions. In order to support 4Tx MIMO transmissions, it is necessary to obtain 4 channel estimates in order to characterize each of the spatial layers, which will require new pilot signals to be defined. Pilots are needed for two main functionalities; channel state information (CSI) estimation through channel sounding where rank, a channel quality indicator (CQI) (also referred to as channel quality information) and a precoding control index (PCI) are estimated and channel estimation for demodulation purposes.
For 4 branch MIMO, at least two different approaches are possible (1) Common pilots for both CSI and channel estimation for data demodulation and (2) Common pilots for CSI estimation and additional pilots for channel estimation for data demodulation.
In the above context, "common pilots" refer to pilots that are made available to all users and which are transmitted without user specific beamforming.
Common pilots may be transmitted at instances in which legacy users (Release 7 MIMO and Release 99), who are not able to demodulate 4TX transmissions are scheduled. These legacy users cannot make use of the energy in the common pilots. However, the energy in the additional common pilots will reduce the amount of energy available for High-Speed Physical Downlink Shared Channel (HS-PDSCH) scheduling to the legacy users. Moreover, the additional pilots cause interference to these users. Therefore, to minimize performance impacts to non 4TX users, it is essential that the power of the common pilots can be reduced to a low value.
In a High-Speed Downlink Packet Access (HSDPA) system, the user equipment (UE) (e.g., communication device) has to periodically report a channel quality indicator (CQI). The period is configured by the higher layers. For the purpose of channel quality reporting the UE has to know the powers of the pilots and the measurement offset (a.k.a., measurement power offset).
In Release 7 MIMO (2×2), for the purpose of CQI reporting, the UE shall assume a total transmit power of HS-PDSCH (PHSPDSCH) is given by:PHSPDSCH=PCPICH+Γ in dB,where the total transmit power is assumed to be evenly distributed among the HS-PDSCH codes corresponding to the reported CQI value, and the measurement power offset Γ (i.e., an offset value) is signaled by higher layers. PCPICH denotes the combined transmit power of a set of CPICH(s) (e.g., a primary CPICH and three secondary CPICHs) used for MIMO operation of the High-Speed Downlink Shared Channel (HS-DSCH).
The base station (e.g., Node B) sends the measurement power offset information through higher order signaling for example Radio Resource Control (RRC) messages. The actual measurement power offset can vary from TTI to TTI since HS-PDSCH power depends upon power transmitted by Node B when user is scheduled. A user can be scheduled every TTI. To reduce overhead, the measurement power offset is signaled preferably only at the start of an HSDPA session. Therefore, the Node B re-computes the actual CQI based on the current or recent measurement power offset and the signaled measurement power offset. The Node B knows the signaled measurement power offset. In a four branch MIMO, it was decided to use two types of pilot solutions. The Node B informs the UE which one of the two to use. In each case, the measurement power offset computation is different. Hence a new method to determine the measurement power offset and convey this information is desired.

Systems and methods for determining measurement power offsets


In a keypad device of the type that includes a unique output function as a consequence of physically adjacent keys or key equivalents operated simultaneously: a continuous elastomeric material with integrally molded key cap structure identifying individual and combination keys of minimal height differential with a sealed cursor control device placed with the key matrix a indentation in a non-exposed side near the center of a plurality of individually actuatable key switches; individual key switches in excess of the number of individual key caps.

Electronic devices continue to become smaller and more complex. As complexity increases, there is a tendency for these devices to require more buttons, including entire alphanumeric character sets, function-specific keys and ultimately cursor control. Combination keypad locks are more difficult to guess when an increased number combinations are possible.
Examples include: desktop and cellular telephonic products capable of accessing the Internet; two-directional hand held written communication devices; remote controls for television set top boxes offering computer functionality or interactive television; combination keypad lock interfaces and wired telephones with peripheral control abilities.
Such devices are problematic because the human hand remains relatively constant in size while the components shrink. The result is that the interface to the hand--the keypad--often dictates the smallest possible size of an electronic device. It is therefore increasingly important to minimize the size of the keypad without reducing the size of the keys to be smaller than the human hand may use comfortably.
Previous efforts to address this issue consist of the following:
Scale the Keypad Smaller
The most obvious way to increase the number of functions in a given area is to scale the keypad smaller, reducing key cap size and decreasing the distance between key cap centers. This technique causes the user to feel constrained. Products which use small keypads suffer from the impression that they are toy-like, largely because, in fact, they are scaled for use by a child. Decreasing key cap size makes the keys less comfortable to the full-sized adult finger. Decreasing the distance between key cap centers increases the likelihood of accidental input. Decreasing the size of the legend reduces legibility and the ease of viewing. In these ways, this solution is workable but far from optimal.
Chorded keyboards
Chorded keyboards have a relatively small number of keys, often linearly disposed to conform with the resting position of the human hand, which operate in combination to form each input, offering 2 raised to the N number of different inputs where N is the number of keys. The primary problem with this solution is that it requires the user to memorize 2 N input combinations and to develop the necessary motor skills. While this is a workable solution for extremely dedicated users, it is impractical and requires an unrealistically large amount of practice for most.
Modal Solutions
There are a variety of solutions in which individual keys are given a plurality of functions: Time variance modality varies the time between key operations to define the output function. This is non-intuitive and severely restricts the pace at which an operator may work; Function key modality alters the functionality of the keystroke(s) which follow in a predetermined manner. While this is an extremely common technique, it has limitations. While a function key doubles the possible outputs of a keypad, it also doubles the number of keystrokes required. Further, it is impractical to reduce the dimension of the standard 10-key keypad or the space required by the 26 letters of the alphabet by implementing a function key solution because the characters of these sets are of near-equal significance; Force sensitive modality incorporates a plurality of force-levels to a single button, and thereby a plurality of functions. Tests show that there is a wide variation in the forces naturally applied by users and wide variations in the levels of force sensitivity between users. The solution is highly non-intuitive. For these reasons, force sensitive keys are not widely applicable, nor desirable.
Smart Keys
There are a variety of solutions in which the character input by any given key is modified as a consequence of the previous letters entered, based on likely probabilities within a given language, such as that provided by Aiki Ltd, a Seattle company. With this technology, the probability of the device guessing correctly increases with the length of word. However, the first letter of each word in always a problem. Obviously any keyswitch technology, including the object of this invention, may be combined with a Smart key solution.
There are further goals beyond the primary objective of providing a tiny, easy-to-use keypad. Because the environment for miniaturized products is one of constant abuse, reliability and robustness are critical. Devices intended to survive within pockets and to be used at the dinner table must be water and crumb proof. Furthermore, the next generation of miniaturized devices will require a cursor control device that can be fully integrated, yet without compromising on overall robustness, manufacturability, or performance. With absolute miniaturization as the goal, even millimeters become significant for the entire product to fit into a pocket or onto a wrist.
What is desirable is a keypad which increases the number of functions which can be output from a given number of keys and within a defined area, without compromising the ergonomic advantages of full-size and individually operable key caps. It is further desirable to not require any learning or practice. The keypad would be non-modal to eliminate the confusion and errors commonly associated with modalities. Each output function would permanently correlate with a single key cap location. The identifying legends would be full-size for easy identification. Functions would be accessible by a single finger push. The keypad would be small without being toy-like because it is designed to accommodate a full-size human finger. Ideally a compact keypad would effect full-sized key caps with on center distances smaller than full-sized key cap dimensions allow. It would be low-cost yet robust, reliable and include a cursor control.
It is therefore a goal of the present invention to provide: a compact keypad in which each function may be actuated comfortably by an adult-sized human finger; an increased number of functions within a given area without compromising the ergonomic advantages of full-size key caps; a compact keypad in which each function may be accessed by a single finger motion; and an increased number of inputs without requiring memorization, training to use, or the introduction of a modality for normal operation.
It is yet further goal to provide a low cost, reliable, ruggedized miniature product that can withstand normal daily activities such as eating, drinking, and being tossed.
It is yet a further goal to decrease the accuracy required to reliably actuate adjacent keys of a keypad in which multiple adjacent keys are operated with a single push of a finger, especially for molded elastomeric sheets operating over printed circuit boards.
It is yet a further goal to reduce the force required to reliably actuate adjacent keys of a keypad in which multiple adjacent keys are operated with a single push of a finger, especially for molded elastomeric sheets operating over printed circuit boards.
It is yet a further goal to eliminate the electronic ambiguities inherent with simultaneous operation of the adjacent keys in a scan matrix.
It is yet still further a goal to provide a cursor control means that may be integrated within the constraints explained above.