The present invention provides, inter alia, dihydropyridone compounds and compositions, including analogs of a vesicular monoamine transporter type 2 (VMAT2) antagonist. The present invention also provides methods of using such compounds/analogs for modulating glucose levels, and/or preventing, treating, or ameliorating the effects of diabetes and hyper-glycemia.

Diabetes mellitus is a growing epidemic affecting hundreds of millions of people worldwide. (Zimmer et al., 2001). Despite a recent explosion of new classes of hypoglycemic agents, the medical need remains largely unmet and innovative diagnostics and therapeutics are still urgently needed.
D-Glucose, with the synergistic effects of certain amino acids, is the major physiological stimulus for insulin secretion (reviewed in (Henquin 2000)). Net insulin production and glucose homeostasis, however, is regulated by a number of other molecules, including several classical neurotransmitters (Ahren 2000; Brunicardi, et al. 1995) that act directly on beta cells, and indirectly through other target tissues such as liver and skeletal muscle. Many of these molecules function as amplifying agents that have little or no effect by themselves, but enhance the signals generated by the beta cell glucose sensing apparatus (Henquin 2000). For example, during the cephalic phase of insulin release, acetylcholine (ACh) is released via islet parasympathetic innervation. Beta cells express the M3 muscarinic receptor (Duttaroy, et al. 2004) and respond to exogenous ACh with increased inositol phosphate production, which in turn facilitates sodium (Na+) ion exit and calcium ion entry. This results in augmented insulin vesicle exocytosis (Barker, at al. 2002).
The amino acid glutamate, the major excitatory neurotransmitter in the central nervous system, is present in both alpha- and beta-cells of the endocrine pancreas. Glutamate is stored in glucagon-containing granules (Hayashi, et al. 2003), and is proposed to enhance insulin secretion when it is released into the vicinity of islet cells (Storto, et al. 2006). The presence of metabotropic glutamate receptors on alpha- and beta-cells themselves suggests the presence of both autocrine and paracrine circuits within islet tissue involved in the regulation of insulin secretion (Brice, et al. 2002).
Other neurotransmitters, such as the monoamines, epinephrine and norepinephine, acting both systemically and via nerve terminals in the vicinity of islets, may act to suppress glucose stimulated insulin secretion by direct interaction with adrenoreceptors expressed (mainly the alpha 2 receptor) on pancreatic beta cells (Ahren 2000; El-Mansoury and Morgan 1998). Beta cells of the endocrine pancreas also express dopamine receptors (D2) and respond to exogenous dopamine with inhibited glucose-stimulated insulin secretion (Ahren and Lundquist 1985; Niswender, et al. 2005; Rubi, et al. 2005; Shankar, et al. 2006). Purified islet tissue is a source of monoamines, and has been shown to contain 5-hydroxytryptamine, epinephrine, norepinephrine and dopamine (Cegrell 1968; Ekholm, et al. 1971; Hansen and Hedeskov 1977; Lundquist, et al. 1989; Niswender et al. 2005; Wilson, et al. 1974).
Beta cells also have the biosynthetic apparatus to create, dispose of, and store specific neurotransmitters. For example, tyrosine hydroxylase, the enzyme responsible for catalyzing the conversion of L-tyrosine to L-3,4-dihydroxyphenylalanine (L-DOPA), a precursor of dopamine, L-DOPA decarboxylase, responsible for converting L-DOPA to dopamine (Rubi et al. 2005) and dopamine beta hydroxylase, the enzyme that catalyzes the conversion of dopamine to norepinephrine, are present in islet tissue (Borelli, et al. 2003; Iturriza and Thibault 1993). Thus, L-DOPA is rapidly converted in islet beta-cells to dopamine (Ahren, et al., 1981; Borelli, et al. 1997).
Monoamine oxidase (MAO) is a catabolic enzyme responsible for the oxidative de-amination of monoamines, such as dopamine and catecholamines, and maintains the cellular homeostasis of monoamines. The possible role of MAO in islet function has been studied, (Adeghate and Donath 1991) and MAO has been detected in both alpha- and beta-cells of pancreatic islet cells, including beta cells (Feldman and Chapman 1975a, b). Interestingly, some MAO inhibitors have been shown to antagonize glucose-induced insulin secretion (Aleyassine and Gardiner 1975). The secretory granules of pancreatic beta cells store substantial amounts of calcium, dopamine and serotonin (Ahren and Lundquist 1985).
In the central nervous system, the storage of monoamine neurotransmitters in secretory organelles is mediated by a vesicular amine transporter. These molecules are expressed as integral membrane proteins of the lipid bilayer of secretory vesicles in neuronal and endocrine cells. An electrochemical gradient provides energy for the vesicular packaging of monoamines, such as dopamine, for later discharge into the synaptic space (reviewed by (Eiden, et al. 2004)). Both immunohistochemistry and gene expression studies show that islet tissue and the beta cells of the endocrine pancreas selectively express only one member of the family of vesicular amine transporters, vesicular monoamine transporter type 2 (VMAT2) (Anlauf, et al. 2003).
VMAT2 is one member of the vesicular transporter family responsible for the uptake and secretion of monoamine neurotransmitters in neurons and endocrine cells. (Zheng et al, 2006) Recent studies have shown the feasibility of noninvasive measurements of the amount of VMAT2 in the pancreas as a useful biomarker of beta cell mass both in humans (R. Goland, et al. 2009) and rodents (Souza, et al. 2006) using [11C] dihydrotetrabenazine (DTBZ) and positron emission tomography, but the possible functional role of VMAT2, as expressed in islet tissue and beta cells, in glucose metabolism has not yet been explored.
As indicated, endogenously synthesized and/or stored monoamine neurotransmitters appear to participate in paracrine regulation of insulin secretion and entrainment of the activity of various cells within islets (Borelli and Gagliardino 2001). Given the important role of vesicular amine transporters in the storage and distribution of monoamine neurotransmitters, the possible of role of VMAT2 in glucose-stimulated insulin secretion was explored using the VMAT2-specific antagonist, tetrabenazine (TBZ) (Scherman, et al., 1983). TBZ acts as a reversible inhibitor of monoamine uptake into granular vesicles of presynaptic neurons (Pettibone, et al. 1984) through its ability to bind to VMAT2 (Scherman 1986) thereby facilitating monoamine degradation by MAO. Monoamine neurotransmitters that are depleted via VMAT2 inhibition by TBZ include serotonin, dopamine, and norepinephrine. Administration of TBZ to rats (plasma elimination with half life, t1/2, equals 2 hours) reduces dopamine levels by 40%, serotonin by 44%, and norepinephrine by 41% in the brain (Lane, et al. 1976).
Although there are other vesicular amine transporters (e.g. vesicular monoamine transporter type 1, or VMAT1), tetrabenazine is highly specific for VMAT2, binds to the transporter with a dissociation constant in the nanomolar range, and displays a more than 10,000-fold reduced affinity towards VMAT1 (Erickson, et al. 1996; Varoqui and Erickson, 1997). Given the known effects of monoamine neurotransmitters on insulin secretion, the expression of VMAT2 by beta cells and the antagonist action of TBZ on monoamine transport, it would be desirable to identify compounds, pharmaceutical compositions and methods to modulate glucose metabolism and insulin secretion to, e.g., prevent, treat, or ameliorate the effects of impaired glucose metabolism, such as, e.g., diabetes and hyperglycemia.

The Trustees of Columbia University in the City of New York


The invention relates to a permeable diaphragm for an electrochemical cell.. The diaphragm consists of a sheet of fibrous, organic polymeric material, obtained from a suspension of the said polymeric material in an organic liquid.. The invention applies to permeable diaphragms for cells for the electrolysis of aqueous sodium chloride solutions.

The present invention relates to a permeable diaphragm for an electrochemical cell, in particular for a cell for the electrolysis of aqueous solutions of alkali metal halides.
It relates more particularly to a permeable diaphragm, for an electrochemical cell, which is made of a fibrous, organic polymeric material.
It is known to use diaphragms based on organic polymers in the fibrous state in electrochemical cells.
Thus, U.S. Pat. No. 4,036,729, in the name of Patil et al., filed on Apr. 10, 1975 and published on July 19, 1977, relates to a permeable diaphragm which consists of a felt formed, on the perforated cathode of an electrolysis cell, from a dispersion of a fibrous polymeric material in an aqueous medium containing acetone and a surface-active agent.
This known diaphragm exhibits the disadvantage that it requires the incorporation of a surface-active agent in the aqueous medium used for its manufacture, so as to permit adequate dispersion of the polymeric material in this medium. It exhibits the additional disadvantage that it requires the addition, to the fibrous polymeric material, of an additive which can be wetted by the aqueous electrolytes, so that the diaphragm can be sufficiently wetted by these electrolytes. Practice has shown that, in the absence of a wettable additive (such as asbestos fibers, mica, talc or particles of titanium dioxide), the diaphragm is generally too hydrophobic to permit its normal use in electrochemical cells for treating aqueous electrolytes, in particular in cells for the electrolysis of aqueous solutions of alkali metal halides.
Furthermore, the known diaphragm described above exhibits the disadvantageous characteristic that it can only be produced from a very specific and expensive variety of polymic fibers, namely fibers obtained by the melt extrusion of a polymer subjected to an intense shear stress in an auxiliary liquid medium. This characteristic of the known diaphragm has the disadvantageous consequence of increasing its cost.
Japanese Patent Application No. 49/124,302, filed on Apr. 6, 1973 by Mitsubishi Rayon Co., Ltd, describes a process for the manufacture of porous sheets, in accordance with which a fibrous polymeric material, generally a fluorinated polymer, is dispersed in an organic liquid, for example a halogenchydrocarbon, and a felt is separated from the resulting organic suspension.

Permeable diaphragm for an electrochemical cell


A landscaping blower nozzle assembly includes an inlet section for allowing air into the assembly, an elbow section and a motor. A nozzle is insertable into the elbow section such that the motor moves the elbow section in a moveable motion back and forth though at least 180 degree of motion for aiding the operator in the movement and removal of leaves and other debris. A breakaway coupler prevents damage to the blower nozzle when coming into contact with a rigid surface or structure. A tensioner assembly prevents distortion of the nozzle tip when subjected to high velocity air from the blower motor.

Leaf and debris blowers are well known in the art and work as powered tools that propel air out of a nozzle. These tools are typically used to move yard debris such as leaves or lawn debris. Leaf blowers are most often powered by either electric or gasoline motors. Moreover, leaf blowers are typically self-contained handheld units, or backpack mounted units that use a handheld wand. The latter is more ergonomic for prolonged use. Larger units may rest on wheels and even use a motor for propulsion. These are sometimes called "walk behind leaf blowers" because they must be pushed by hand to be operated. Some units can also be towed behind a vehicle and may be difficult to operate due to their distance from the operator.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.


The adhesion of a sputter-resistant layer is improved by providing the layer with a fairly high quantity of glass frit, in which the frit and the sputter-resistant material have a mass ratio Mfrit/Msrm of 0.9 or more.

The invention relates to a picture display device comprising at least one compartment containing an ionizable gas, in which walls of the compartment are provided with electrodes for selectively generating a plasma discharge of the ionizable gas during operation, and an electro-optical layer of a material having an optical property which is dependent on the discharge state of the plasma discharge.
Picture display devices for displaying monochromatic or color images comprise, inter alia, plasma-addressed liquid crystal display devices, referred to as PALC displays, and (DC) plasma display panels (PDPs). The PALC displays and PDPs are used as television and computer displays and are preferably of the flat-panel type.
A picture display device of the type described in the opening paragraph is known from PCT patent application WO-A-99/04408 (PHN 16458). The flat-panel picture display device described in this document comprises a display screen having a pattern of (identical) data storage or display elements and a multitude of compartments. The compartments are filled with an ionizable gas and provided with electrodes for (selectively) ionizing the ionizable gas during operation. In the known picture display device, the compartments have the shape of parallel, elongate channels (formed in a channel plate) which function as selection means for the picture display device (the plasma-addressed row electrodes). By applying a DC voltage difference across the electrodes in one of the channels of the channel plate, electrons are emitted (from the cathode) which ionize the ionizable gas, thereby forming a plasma (plasma discharge). When the voltage across the electrodes in one channel is switched off and the gas is de-ionized, a subsequent channel is switched on. On the display screen side of the picture display device, the compartments are closed by a (thin) dielectric layer (xe2x80x9cmicrosheetxe2x80x9d). The picture display device further comprises a layer of an electro-optical material provided between the channel plate and a substrate provided with further electrodes which function as the data electrodes or column electrodes of the picture display device. The picture display device is formed by the assembly of the channel plate with the electrodes and the ionizable gas, the dielectric layer, the layer of the electro-optical material and the substrate with the further electrodes.
In the known picture display device, the light transmissibility of the electro-optical layer is determined, during operation, by the plasma, discharge (also dependent on the voltage at the column electrodes).
In a plasma display panel, a plasma discharge is used to directly excite a layer comprising electroluminescent phosphors of display elements, in which (electrons of) the ionized gas in the compartment itself excite(s) the phosphors. In an alternative embodiment of a plasma display panel, a plasma discharge is used to generate light (for example, UV light) in which the light excites a layer comprising photoluminescent phosphors of display elements.
In the known display device, the energy consumption of such picture display devices is reduced by providing at least one of the electrodes with a layer comprising particles of a sputter-resistant material.
Since a (DC) plasma discharge is used in the picture display device, the electrodes in the compartment are subject to an ion bombardment and, generally, the electrodes are made of a sputter-resistant material, or the electrodes are preferably provided with a sputter-resistant layer. The use of sputter-resistant material increases the resistance of the electrodes against sputtering. In said patent application, at least one of the electrodes is provided with such a layer comprising (macroscopic) particles of a sputter-resistant material or xe2x80x9crefractory materialxe2x80x9d.
Practice has proved that such a layer comprising a sputter-resistant material generally adheres poorly to the electrodes. It is an object of the present invention to obviate this drawback.
To this end, a picture display device according to the invention is characterized in that at least one of the electrodes is provided with a layer comprising sputter-resistant material and a frit, in which the frit and the sputter-resistant material have a mass ratio Mfrit/Msrm of at least 0.9, in which Mfrit and Msrm represent the mass of frit and the mass of sputter-resistant material, respectively, per surface unit.
The mass ratio Mfrit/Msrm is preferably at least 1 or more. It has been found that very satisfactorily adhesive layers can be obtained with these ratios. At a mass ratio from about 3.5, however, the generated plasma is unstable.
Sputter-resistant material suitable for the purpose of the invention comprises rare earth borides, for example LaB6 or GdB6, or ruthenium oxide (RuO2).
The sputter-resistant material can be prepared with the frit which is, for example, a glass frit in the suitable mixing ratio and subsequently provided on the electrodes.
In an alternative embodiment according to the invention, the layer of sputter-resistant material is provided on a (glass) frit on (at least one of) the electrodes. By manufacturing the layer in two steps, parts of the sputter-resistant material fill pores of the (glass) frit layer. In this respect it is to be noted that WO-A-99/04408 (PHN 16458) already states the possibility of improving the adhesion of the layer by adding very finely ground glass frit (typical grain sizexe2x89xa61 xcexcm) to the particles of the sputter-resistant material. In contrast to the present invention, a small quantity of frit is chosen in the method described in this document, because the presence of frit particles generally does not lead to a reduction of the effective surface of the sputter-resistant material, which is undesirable for a maximal secondary emission coefficient of the layer of sputter-resistant material.


A DSL modem with a receiver and a transmitter includes an LDPC encoder which utilizes a generation matrix G which is derived from a substantially deterministic H matrix in order to generate redundant parity bits for a block of bits. The H matrix is determined by assigning xe2x80x9conesxe2x80x9d of a first column Nj randomly or deterministically. Then, beginning with the second column, assignment of xe2x80x9conesxe2x80x9d is carried out deterministically with each xe2x80x9c1xe2x80x9d in a previous ancestor column generating a xe2x80x9c1xe2x80x9d in the next descendant column based on the rule that a descendant is placed one position below or above an ancestor. As a result, descending or ascending diagonals are generated. When distributing xe2x80x9conesxe2x80x9d in any given column, care is taken to ensure that no rectangles are generated in conjunction with other xe2x80x9conesxe2x80x9d in the current column and previous columns. By avoiding generation of rectangles, diagonals are interrupted.

1. Field of the Invention
The present invention relates generally to telecommunications. More particularly, the present invention relates to DSL modems utilizing low density parity check (LDPC) codes and methods of simply generating such LDPC codes.
2. State of the Art
LDPC codes were invented by R. Gallager in 1963. R. G. Gallager, xe2x80x9cLow-Density-Parity-Check Codesxe2x80x9d, MIT Press, Cambridge, Mass. 1963. Over thirty years later, a number of researchers showed that LDPC code is a constructive code which allows a system to approach the Shannon limit. See, e.g., D. J. C. MacKay and R. M. Neal, xe2x80x9cNear Shannon limit performance of LDPC codesxe2x80x9d, Electron. Letters, Vol. 32, No. 18, August 1996; D. J. C. MacKay, xe2x80x9cGood Error-Correcting Codes Based on Very Sparse Matricesxe2x80x9d, IEEE Transactions on Information Theory, Vol. 45, No. 2, March 1999; D. J. C. MacKay, Simon T. Wilson, and Matthew C. Davey, xe2x80x9cComparison of Constructions of Irregular Gallager Codesxe2x80x9d, IEEE Transactions on Communications, Vol. 47, No. 10, October 1999; Marc P. C. Fossorier, Miodrag Michaljevic, and Hideki Imai, xe2x80x9cReduced Complexity Iterative Decoding of LDPC Codes Based on Belief Propagationxe2x80x9d, IEEE Transactions on Communications, Vol. 47, No. 5, May 1999; E. Eleftheriou, T. Mittelholzer, and A. Dholakia, xe2x80x9cReduced-complexity decoding algorithm for LDPC codesxe2x80x9d, Electron. Letter, Vol. 37, January 2001. Indeed, these researchers have proved that LDPC code provides the same performance as Turbo-code and provides a range of trade-offs between performance and decoding complexity. As a result, several companies have suggested that LDPC code be used as part of the G.Lite.bis and G.dmt.bis standards. IBM Corp., xe2x80x9cLDPC codes for G.dmt.bis and G.lit.bisxe2x80x9d, ITU-Telecommunication Standardization Sector, Document CF-060, Clearwater, Fla., Jan. 8-12, 2001; Aware, Inc., xe2x80x9cLDPC Codes for ADSLxe2x80x9d, ITUxe2x80x94Telecommunication Standardization Sector, Document BI-068, Bangalore, India, Oct. 23-27, 2000; IBM Corp., xe2x80x9cLDPC codes for DSL transmissionxe2x80x9d, ITUxe2x80x94Telecommunication Standardization Sector, Document BI-095, Bangalore, India, Oct. 23-27, 2000; IBM Corp., xe2x80x9cLDPC coding proposal for G.dmt.bis and G.lite.bisxe2x80x9d, ITUxe2x80x94Telecommunication Standardization Sector, Document CF-061, Clearwater, Fla., Jan. 8-12, 2001; IBM Corp., Globespan, xe2x80x9cG.gen: G.dmt.bis: G.Lite.bis: Reduced-complexity decoding algorithm for LDPC codesxe2x80x9d, ITUxe2x80x94Telecommunication Standardization Sector, Document IC-071, Irvine, Calif., Apr. 9-13, 2001.
LDPC code is determined by its check matrix H. Matrix H is used in a transmitter (encoder) for code words generation and in a receiver (decoder) for decoding the received code block. The matrix consists of binary digits 0 and 1 and has size Mk*Mj, where Mk is the number of columns, and Mj is the number of rows. Each row in the matrix defines one of the check equations. If a xe2x80x9c1xe2x80x9d is located in the k-th column of the j""th row, it means that the k-th bit of the code block participates in the j-th check equation.
Matrix H is a xe2x80x9csparsexe2x80x9d matrix in that it does not have many xe2x80x9conesxe2x80x9d. Generally, the matrix contains a fixed number of xe2x80x9conesxe2x80x9d N in each column and a fixed number of xe2x80x9conesxe2x80x9dNk in each row. In this case, design parameters should preferably satisfy the equation:
Mk*Nj=Mj*Nkxe2x80x83xe2x80x83(1)
Although it is convenient to have equal numbers of xe2x80x9conesxe2x80x9d in each column and in each row, this is not an absolute requirement. Some variations of design parameters Nk and Nj are permissible; i.e., Nk(j) and Nj(k) can be functions of j and k, correspondingly. In addition, another important constraint for matrix design is that the matrix should not contain any rectangles with xe2x80x9conesxe2x80x9d in the vertices. This property is sometimes called xe2x80x9celimination of cycles with length 4xe2x80x9d or xe2x80x9c4-cycle eliminationxe2x80x9d. For purposes herein, it will also be called xe2x80x9crectangle eliminationxe2x80x9d.
Generally, there are two approaches in the prior art to designing H matrices. The first approach was that proposed by Gallager in his previously cited seminal work, R. G. Gallager, xe2x80x9cLow-Density-Parity-Check Codesxe2x80x9d, MIT Press, Cambridge, Mass. 1963, and consists of a random distribution of Nj ones within each matrix column. This random distribution is carried out column by column, and each step is accompanied by rectangle elimination within the current column relative to the previous columns. The second approach to H-matrix design is based on a deterministic procedure. For example, in the previously cited IBM Corp., xe2x80x9cLDPC codes for G.dmt.bis and G.lit.bisxe2x80x9d, ITUxe2x80x94Telecommunication Standardization Sector, Document CF-060, Clearwater, Fla., Jan. 8-12 2001, a deterministic H-matrix construction is proposed which includes identity matrices and powers of an initial square permutation matrix.
Both of the prior art approaches to designing H matrices have undesirable characteristics with respect to their implementation in DSL standards. In particular, the random distribution approach of Gallager is not reproducible (as it is random), and thus, the H matrix used by the transmitting modem must be conveyed to the receiving modem. Because the H matrix is typically a very large matrix, the transfer of this information is undesirable. On the other hand, while the deterministic matrix of IBM is reproducible, it is extremely complex and difficult to generate. Thus, considerable processing power must be dedicated to generating such a matrix, thereby adding complexity and cost to the DSL modem. Besides, this approach does not allow constructing a matrix with arbitrary design parameters Mk and Mj.
It is therefore an object of the invention to provide simple methods of generating reproducible H matrices.
It is another object of the invention to provide DSL modems which utilize simply generated reproducible H matrices.
In accord with these objects which will be discussed in detail below, the DSL modem of the invention generally includes a receiver and a transmitter with the transmitter including a substantially deterministic LDPC encoder. The encoder is a function of a substantially deterministic H matrix (H=A|B) which is determined according to the steps and rules set forth below. More particularly, the encoder takes a block of bits and utilizes a generation matrix G=Axe2x88x921B which is derived from (i.e., is a function of) the H matrix in order to generate redundant parity bits. The redundant bits are appended to the original block of bits to generate a word.
The substantially deterministic H matrix is determined as follows. First, the xe2x80x9conesxe2x80x9d of a first column N are assigned randomly or deterministically. Preferably, the ones are distributed evenly within the first column with the first xe2x80x9c1xe2x80x9d in the first row of the first column according to the algorithm:
H(r,1)=1, where r=1+(ixe2x88x921)*integer (Mj/Nj); i=1,2, . . . Njxe2x80x83xe2x80x83(2)
Then, beginning with the second column, assignment of xe2x80x9conesxe2x80x9d is carried out deterministically with each xe2x80x9c1xe2x80x9d in a previous (ancestor) column generating a xe2x80x9c1xe2x80x9d in the next (descendant) column based on the rule that a descendant is placed one position below or one position above an ancestor (it being determined in advance by convention whether the position below is used or the position above is used). As a result, a descending diagonal or an ascending diagonal is generated. Where a descending diagonal is used and the ancestor is in the lowest row of the matrix, the descendant may take any position in the next column, although it is preferable to place the descendant in the highest free position.
When distributing xe2x80x9conesxe2x80x9d in any given column, each new descendant should be checked to ensure that no rectangles are generated in conjunction with other xe2x80x9conesxe2x80x9d in the current column and previous columns. If a rectangle is generated, the location of the descendant is changed, preferably by shifting the location down or up (by convention) one position at a time until the descendant is in a position where no rectangle is generated. If the position is shifted down and the lowest position is reached without finding a suitable position, the search is continued by shifting the location one position up from the initial descendant position until a suitable position is found.
According to the invention, the descendants may be generated in any given order. Two preferable generation orders correspond to increasing or decreasing ancestor positions in the column. For example, descendants may be generated by first generating a descendant for the ancestor at the bottom of the matrix, then by generating a descendant for the ancestor above that in the column, then by generating a descendant for the ancestor above that one, etc. (also called herein xe2x80x9cbottom-upxe2x80x9d); or by first generating a descendent for the ancestor at the top of the matrix, then by generating a descendant for the ancestor below that in the column, then by generating a descendant for the ancestor below that one, etc. (also called herein xe2x80x9ctop-downxe2x80x9d).
When generating descendants it is possible that one or more descendants can xe2x80x9cdisappearxe2x80x9d because of the lack of free positions satisfying the rectangle elimination criterium. To regenerate the xe2x80x9clost descendantxe2x80x9d, it is generally sufficient to change the order of descendant generation for that column. Thus, if the order of descendant generation was conducted xe2x80x9cbottom-upxe2x80x9d, the direction of generation is switched to xe2x80x9ctop-downxe2x80x9d and vice versa; preferably for that column only. If changing the order of descendant generation in a column does not cause a free position to appear, the descendant disappears for that column.
When a descendant disappears it is desirable in the next column to provide a new descendant which does not have an ancestor. In this case, a search of an acceptable position for an xe2x80x9cancestor-lessxe2x80x9d descendant is conducted, preferably from the first row down.
Additional objects and advantages of the invention will become apparent to those skilled in the art upon reference to the detailed description taken in conjunction with the provided figures.

DSL modem utilizing low density parity check codes


A pretreatment process is disclosed for increasing conversion and reducing the fouling rate of reforming catalysts wherein the catalyst is pretreated at a temperature from 1025.degree. F. to 1275.degree. F. in a reducing atmosphere prior to contacting the catalyst with a hydrocarbon feed in the presence of hydrogen.

The present invention concerns a pretreatment method useful for increasing the conversion and lowering the fouling rate of a reforming catalyst.
Catalytic reforming is a well-known process that is used for raising the octane rating of a naphtha for gasoline. The reactions that occur during reforming include: dehydrogenation of cyclohexanes, dehydroisomerization of alkylcyclopentanes, dehydrocyclization of acyclic hydrocarbons, dealkylation of alkylbenzenes, isomerization of paraffins, and hydrocracking of paraffins. The hydrocracking reaction should be suppressed because that reaction lowers the yield of hydrogen and lowers the yield of liquid products.
Reforming catalysts must be selective for dehydrocyclization, in order to produce high yields of liquid product and low yields of light gases. These catalysts should possess good activity, so that low temperatures can be used in the reformer. Also, they should possess good stability, so that they can maintain a high activity and a high selectivity for dehydrocyclization over a long period of time.
While most reforming catalysts contain platinum on an alumina support, large-pore zeolites have been proposed as supports. These large-pore zeolites have pores large enough for hydrocarbons in the gasoline boiling range to pass through. Commercial application of zeolitic reforming catalysts have thus far been very limited, although certain catalysts comprising a large-pore zeolite containing at least one Group VIII metal have a very high selectivity for dehydrocyclization.
It is known that reforming catalysts require pretreatment prior to utilizing these catalysts for reforming naphtha feedstocks. For example, U.S. Pat. No. 4,517,306 issued to Waldeen Buss on May 14, 1985 claims a composition comprising: (a) a type L zeolite; (b) at least one Group VIII metal; and (c) an alkaline earth metal selected from the group consisting of barium, strontium and calcium, wherein said composition is reduced in a hydrogen atmosphere at a temperature of from 480.degree. C. to 620.degree. C. (896.degree. to 1148.degree. F.). It is preferred that the composition be reduced at a temperature from 550.degree. to 620.degree. C. (1022.degree. to 1148.degree. F.).
U.S. Pat. No. 4,539,304 issued on Sep. 3, 1985 to Field discloses a two-step pretreatment process for increasing the conversion of reforming catalysts wherein the catalyst is first treated at a temperature of from 120.degree. C. (248.degree. F.) to 260.degree. C. (500.degree. F.) in a reducing gas. In the second step, the temperature of the catalyst is maintained at 370.degree. C. (698.degree. F.) to 600.degree. C. (1112.degree. F.) in a reducing atmosphere.
U.S. Pat. No. 4,539,305 issued on Sep. 3, 1985 to Wilson et. al. discloses a pretreatment process for enhancing the selectivity and increasing the stability of a reforming catalyst comprising a large-pore zeolite containing at least one Group VIII metal. The catalyst is reduced in a reducing atmosphere at a temperature of from 250.degree. C. (482.degree.) to 650.degree. (1202.degree. F.). The reduced catalyst is subsequently exposed to an oxygen-containing gas and then treated in a reducing atmosphere at a temperature of from 120.degree. C. (248.degree. F.) to 260.degree. C. (500.degree. F.). Finally, the catalyst is maintained at a temperature of from 370.degree. C. (698.degree. F.) to 600.degree. C. (1112.degree. F.) in a reducing atmosphere. Preferably, the first reduction step is carried out in the presence of hydrogen.
U.S. Pat. No. 5,155,075 issued to Innes et. al. shows an initial catalyst reduction at 300.degree. F. to 700.degree. F., followed by a temperature ramp up to a final hydrogen treatment temperature between 900.degree. F. and 1000.degree. F.
U.S. Pat. No. 5,066,632 issued on Nov. 19, 1991 to Baird et. al. discloses a process for pretreating a catalyst useful for reforming a naphtha wherein the catalyst is calcined at temperatures in excess of 500.degree. F., preferably at temperatures ranging from 500.degree. F. to about 750.degree. F. in air or in atmospheres containing low partial pressures of oxygen or in a non-reactive or inert gas such as nitrogen. The catalyst is then contacted with a dry hydrogen-containing gas at a temperature ranging from about 600.degree. F. to about 1000.degree. F., preferably from about 750.degree. F. to about 950.degree. F., at a hydrogen partial pressure ranging from about 1 atmosphere to about 40 atmospheres, preferably from 5 atmospheres to about 30 atmospheres.
European Patent Application Publication Number 243,129 discloses a catalyst activation treatment with hydrogen at temperatures from 400.degree. C. (752.degree. F.) to 800.degree. C. (1472.degree. F.), preferably from 400.degree. C. (752.degree. F.) to 700.degree. C. (1292.degree. F.) for a catalyst used for cracking a hydrocarbon feedstock. The treatment pressure may vary from 100 to 5,000 MPa but is preferably from 100 to 2,000 MPa. A carrier gas which contains 1-100% v/v, preferably from 30-100% v/v, of hydrogen is used.
U.S. Pat. No. 4,717,700 issued to Venkatram et. al. discloses a method for drying a zeolite catalyst by heating while in contact with a gas. The rate of catalyst temperature increase is controlled so as to limit the rate of water evolution from the catalyst and the water vapor concentration in the gas. The gas used to heat the catalyst is gradually increased in temperature at about 28.degree. C. per hour. The moisture level of the effluent gas is preferably between 500 and 1500 ppm during the drying step. The catalyst drying method with a subsequent reduction with hydrogen wherein the temperature is raised to a maximum temperature of 450.degree. C. is exemplified in Example 1.
Austrian Patent Specification No. 268,210 relates to a metal-charged zeolite molecular sieve, which is suitable as a catalyst for the conversion of hydrocarbons. Methods for preparing the catalyst are described. It is disclosed that the catalyst prepared by such methods usually has a high water content and that it is desirable to activate the catalyst before use since the catalyst is sensitive to water. The recommended activation process comprises: 1) slow heating of the catalyst in air at 300.degree. to 600.degree. C., preferably 500.degree. C.; followed by 2) slow heating of the catalyst from room temperature to approximately 500.degree. C. in a current of hydrogen gas under atmospheric pressure.
A pretreatment process of Pt-Al.sub.2 O.sub.3 catalysts in hydrogen in the temperature range of 450.degree. C. (842.degree. F.) to 600.degree. C. (1112.degree. F.) is disclosed in Journal of Catalysis (1979); Vol. 59, p. 138 (P. G. Menon and G. F. Froment). The effect of catalyst reduction temperature on the conversion of n-pentane and n-hexane using Pt-Al.sub.2 O.sub.3 catalysts is disclosed. For the Pt-Al.sub.2 O.sub.3 catalyst reduced at 400.degree. C. (752.degree. F.), hydrogenolysis is the main reaction; whereas for the Pt-Al.sub.2 O.sub.3 catalyst reduced at 600.degree. C. (1112.degree.), the hydrogenolysis and total activity are considerably suppressed. This reference specifically discloses the effect of a hydrogen pretreatment process on Pt-Al.sub.2 O.sub.3 catalysts and does not disclose the effect of hydrogen pretreatment on zeolitic catalyst.
Additionally, the effects of hydrogen pretreatment of the Pt-Al.sub.2 O.sub.3 catalyst with respect to isomerization is disclosed. The activity for dehydrocyclization was not increased.
Prior art processes have observed both a reduced catalytic activity and reduced hydrogen chemisorption for catalysts which have been reduced at temperatures in excess of 500.degree. C. Furthermore, there has been no clear understanding of the phenomena which occur during high temperature catalyst reduction. Thus, reduction at high temperatures may result in strongly chemisorbed hydrogen, may cause loss of spillover hydrogen altering the local charge transfer from the support to the metal at the particle boundary, may induce changes in morphology of the metal crystallite, or may affect reduction of the support resulting in the formation of an alloy with atoms from the support.

Pretreatment method for increasing conversion of reforming catalyst

Chevron Research & Technology Co., a Div. of Chevron U.S.A. Inc.


In a workpiece supporting device for supporting a workpiece, a holding shaft carrying at its one end a center member adapted to support one end of the workpiece is slidably received in a housing. A hydraulic cylinder is formed in the housing and a sleeve member is rotatably mounted on a piston rod of the hydraulic cylinder with a connecting member being threadedly engaged with the sleeve member. A spring is adjustably interposed between the holding shaft and the connecting member and relative axial movement between the holding shaft and the connecting member is limited within a predetermined distance.

1. Field of the Invention:
The present invention relates to a workpiece supporting device for supporting a workpiece by center members.
2. Description of the Prior Art:
The conventional workpiece supporting device for supporting a workpiece by center members is somewhat satisfactory in performing its intended function. However, the device is complicated in construction, thus necessarily making it relatively expensive in cost.
Moreover, since the hydraulic actuator for moving the holding shaft carrying the center member toward and away from the workpiece is also connected to act on a spring for applying a holding force to the workpiece being supported by the center members, the spring is excessively compressed each time the hydraulic actuator is operated to retract the holding shaft from the workpiece. Therefore, there is a possibility that the spring will be damaged by repeated excessive compression.
Furthermore, such conventional device cannot meet the requirement that the holding shaft be accurately adjusted to a desired position for supporting, for example, workpieces with the same length but with slightly different center bores.


A molded part and a method for producing the molded part. The molded part is rotationally symmetrical or at least partially annular in cross section and formed by a plasticized polymeric mass containing fibers being injected through an injection opening into a cavity of a molding tool. Once the polymeric mass has solidified, the molded part is removed from the tool. Injection into the cavity takes place through at least two injection openings in such a way that the fibers are aligned predominantly in the main stress directions of axial tension and torsion in the molded part.

Injection molding is a known discontinuous molding method used for plastic materials. Injection molding allows the production of a large quantity of molded parts, with high accuracy, which can immediately be used industrially. For this purpose, the material and/or molding mass is plasticized in an injection unit of an injection molding machine and injected into an injection molding tool. Modern injection molding machines work with a screw conveyer which plasticizes, conveys and injects the molding mass into the tool. The polymeric mass solidifies in the cavity and/or mold cavity of the tool, whereupon the molded part can be removed from the tool. A volume contraction resulting from solidification can basically—however, only to a certain extent—be compensated by a holding pressure applied prior to removal of the part.
Certain thermoplastics, duroplastics and elastomers can be processed by means of injection molding. Using masses containing fibers in injection molding thermoplastics has also been known, whereby molded parts with comparatively higher strength can be produced. During injection molding, the mass temperature is approx. between 100° C. and 350° C., the injection pressure approx. between 400 bar and 1600 bar and the tool temperature approx. between 40° C. and 160° C. When processing thermoplastics, the conveyor screw is relatively warm in order to melt the thermoplastic material. In contrast, the tool is relatively cold in order to cool the just molded part. When processing duroplastics, the temperature of the plasticizing unit has to be adjusted to the flow and cure behavior and is therefore in general lower than for thermoplastics, while the tool has to be kept warmer than the injection unit so that the mass can adequately harden there.
In contrast to calandering, by means of which only plane layers of uniform thickness can normally be produced, in injection molding, the hollow space of the tool, the so-called cavity, determines the shape and superficial structure of the finished part, so that molded parts of the type mentioned above—with rotationally symmetrical or in particular at least partially annular cross section—can be produced in a single operation by injection molding. For this purpose, the plasticized polymeric mass is injected into the cavity through an injection opening, whereby the mass flows in an annular manner around an inner core of the tool, and merges at the side opposite the injection opening. A weld line results at this point, which normally has a lower strength than the remaining body of the molded part.
It is the object of the present invention to provide a method of the type mentioned above, by means of which a molded part with a rotationally symmetrical, in particular, annular, or at least partially annular cross section, such as a nut, a collar, a pipe connector, a pipe coupling or similar part, can be produced with improved strength in the stress direction and, preferably, also controlled shrinkage and warping during solidification of the polymeric mass using simple technology.

Method for producing a screw part with an annular cross-section


A round baler having a frame with opposing side walls, a series of inwardly facing moving surfaces defining a baling chamber for forming cylindrical packages of crop material, a pick up for feeding crop material into the chamber, a plurality of rotatable transverse rollers mounted between the opposing side walls of the frame, and a support assembly for mounting at least one of the rollers. The support includes a bearing assembly having a generally cylindrical stationary first race and a concentrically disposed generally cylindrical rotatable second race between which races a bearing cavity is formed for seating a series of bearings housed between the first and second races. The second race is rotatable with the one roller relative to the first race. A generally concentric ring shaped outer member, affixed to the outer race, includes a plurality of integral ribs extending radially and outwardly from the outer member to engage crop residue and urge it away from the journal under conditions where the roller is rotating.

Agricultural machines towed by a tractor across a field for picking up windrowed crop material to form a cylindrical bale are commonly referred to as round balers. These machines have either a fixed or an expandable bale forming chamber disposed between opposing vertical sidewalls. The chamber is usually defined by a floor and transverse confining means comprising a continuous flexible apron and/or a plurality of transverse rolls. Frequently the apron includes an array of side-by-side belts trained around a series of rollers that extend between the sidewalls, and the floor consists of either a large roller or a continuous conveyor belt.
During field operation, crop material such as hay is picked up from the ground and fed into the chamber. The volume of crop material increases continuously in the chamber until a compact cylindrical package is formed. The package is wrapped while still in the chamber and then ejected onto the ground as a completed bale.
Round balers of the general type mentioned above comprising a chamber defined at least partially by a plurality of side-by-side, longitudinally extending belts supported on a plurality of transverse rollers have encountered problems of varying degree caused by trash, such as stray crop material and other debris, that finds its way into the mounting bearings for the transverse rollers. When the crop material being baled is damp, and particularly if it is a short cut of grass crop, fine random debris from the crop material being formed into a cylindrical package in the chamber is also a cause for concern. Field experience has shown that standard bearing seals when continuously exposed to unwanted trash are not sufficient to prevent debris from working its way into the bearing cavity. Eventually, if permitted to go uncorrected, serious wear problems may occur culminating in bearing failure.
In one known round baler where these problems could occur the configuration includes an apron having an expandable inner course of side-by-side belts which cooperates with a sledge assembly to define a bale chamber which expands between a bale starting position and a full bale position. The sledge assembly includes a plurality of driven rollers and an idler roller in engagement with the apron belts to maintain the apron in close proximity to one of the driven rollers during movement of the sledge assembly between the bale starting and full bale positions. The idler roller is commonly referred to as a follower roll. This type of baler is disclosed in U.S. Pat. No. 4,870,812, issued Oct. 3, 1989 in the name of Richard E. Jennings, et al.
In round balers of this type, as well as all other types, durability and reliability are very important design concerns. For example, as mentioned above, serious problems arise under conditions where trash is permitted to build up in the roll bearing area resulting in down time and costly repair if not rectified on a timely basis. Of specific concern are the bearings for rolls located in particularly critical areas insofar as crop residue and debris being trapped are concerned. An example of such an area is the follower roll on the sledge assembly of the baler disclosed in U.S. Pat. No. 4,870,812, mentioned above.
Various prior art round balers have been provided with mechanisms that address the problem of unwanted trash accumulation. For example, adjacent belt paths have been transversely staggered at a particular point along their path to provide egress between adjacent belts for trapped debris as shown in U.S. Pat. No. 4,399,746, issued Aug. 23, 1983 in the name of Jean Viaud. Twisted belts have also been employed on round balers in another attempt to solve the same problem of trapped debris, which approach is disclosed in U.S. Pat. No. 4,707,974, issued Nov. 24, 1987.
In other prior art efforts to remove unwanted trash from round balers, active discharge mechanisms have been utilized, such as the transverse belt arrangement shown in U.S. Pat. No. 5,080,009, issued Jan. 14, 1992 in the name of David P. Fritz, et al, and rotating elements projecting between the belts as shown in U.S. Pat. No. 5,090,760, issued Mar. 24, 1992 in the name of Howard J. Ratzlaff, et al. In still another arrangement a passive discharge arrangement has been used wherein a discharge gate is provided in the rear section of the baler sidewall as disclosed in U.S. Pat. No. 4,444,098, issued Apr. 24, 1984 in the name of Gust S. Soteropulos.
The problem of trash accumulation in critical areas of and round balers is troublesome in varying degree throughout all baling conditions from the extremes of high moisture hay to low moisture hay or straw. When trash accumulates and eventually becomes entrapped or wraps in the roller bearing areas potentially significant problems could arise having a serious effect on baler performance.

Trash removal apparatus for a round baler


A liquid crystal display and a display device, when the liquid crystal display is powered on, a pixel electrode and a common electrode form an electric field, and liquid crystal molecules are deflected under the action of the electric field. However, due to network of the polymer, the liquid crystal polymer is in a scattering state which destroys the condition of total reflection of light from a backlight between two substrates, in such a manner that at least part of light from the backlight is scattered by the liquid crystal polymer and then is emitted from one side of a first substrate. When the liquid crystal display is in an off-state, a long-axis direction of the liquid crystal molecules in the liquid crystal polymer is the same as an extending direction of a long-chain in the liquid crystal polymer, and the liquid crystal polymer is in a transparent state.

A liquid crystal display generally includes an upper substrate and a lower substrate; a liquid crystal layer located between the upper substrate and the lower substrate; a pixel electrode and a common electrode for producing an electric field on both sides of the liquid crystal layer; an upper polarizer positioned on an outer side of the upper substrate, a lower polarizer on an outer side of the lower substrate; and a backlight.
With the development of display technology, transparent displays based on the liquid crystal display attract more and more attention from people, especially, the transparent displays are widely used in places such as shop windows, buildings, vehicles. However, the conventional transparent liquid crystal displays have the problem of low transmittance.

This patent is subject to a terminal disclaimer.

Liquid crystal display and display device


A first operation member includes a first sidewall and a first engaged part. A second operation member includes a second sidewall and a second engaged part. A holding member includes a holding member main body, a first engagement part, a second engagement part, an elastically deformable part, a first limiting part, and a second limiting part. The elastically deformable part elastically deforms in a manner that the first engagement part is displaced in a direction away from the first limiting part until insertion of the first engaged part into between the first engagement part and the first limiting part is allowed, and elastically deforms in a manner that the second engagement part is displaced in a direction away from the second limiting part until insertion of the second engaged part into between the second engagement part and the second limiting part is allowed.

1. Field of the Invention
The present invention relates to a press operation device used in an electronic equipment provided in a vehicle and the like.
2. Description of Related Art
Conventionally, as an operation device installed in various electronic equipments, a press operation device is known. For example, in a case of being installed in a vehicle such as a car, such a press operation device is used for operating an electronic equipment of the vehicle such as an air conditioner, a car navigation system, or a car audio system.
An example of such a press operation device is disclosed in the following Patent Document 1. This press operation device is provided with a plurality of operation members 110 (FIG. 9) and a holding member 130 (FIG. 10) holding the operation members 110. As illustrated in FIG. 9, the operation member 110 includes an operated part 111 that is press-operated, sidewalls 112 formed on a back side of the operated part 111, and engaged parts 113 that are engaged by the holding member 130. As illustrated in FIG. 10, the holding member 130 includes a plurality of holding parts 132 divided from each other by a partition wall 131. The holding parts 132 each have a shape capable of respectively holding each of the operation members 110. Further, each of the holding parts 132 includes a first insertion hole 133 and a second insertion hole 134 allowing the engaged parts 113 of the operation member 110 to be respectively inserted thereinto. The engaged parts 113 are respectively inserted into the insertion holes 133, 134 and become in contact with a back side of the holding member 130. Thereby, the operation member 110 is held by the holding part 132.
Patent Document 1: Japanese Patent Laid-Open Publication No. 2011-009132
In the press operation device described in Patent Document 1, in order to allow insertion of the engaged parts 113, a dimension of each of the insertion holes 133, 134 in an aligned direction (left-right direction in FIG. 10) of the insertion holes must be configured to be larger than a thickness dimension that is a sum of a dimension of the sidewall 112 in the aligned direction and a dimension of the engaged part 113 in the aligned direction. This can lead to problems, for example, such as the following.    (1) In a case such as when an impact is applied to the press operation device, the engaged parts 113 of the plurality of the operation members 110 may slip out from respective insertion holes 133, 134. Therefore, there is a possibility that the operation members 110 may simultaneously drop out from the holding member 130.    (2) The holding member 130 is prevented from being reduced in size in the aligned direction, which prevents the operation member 110 from being reduced in size in the same direction. Specifically, there is a case where a light source for illuminating the operated part 111 of the operation member 110 is provided on a printed circuit board arranged on the back side of the holding member 130. In this case, in order to secure an illumination range of the light source, it is necessary that a dimension between the first insertion hole 133 and the second insertion hole 134 of the holding part 132 in the aligned direction be equal to or larger than a predetermined dimension. As described above, the dimension of each of the insertion holes 133, 134 in the aligned direction is configured to be larger than the thickness dimension. Therefore, it is unavoidable that the holding parts 132 each become large in the aligned direction and thus it is also unavoidable that the operation members 110 each become large in the aligned direction. \


A process of filtering digital images to reduce image flicker. An anti-flicker filtering is performed after a step of calculating the image and before a step of displaying the image so that the flicker is filtered as soon as the image is created.

1. Field of the Invention
This invention generally relates to processing of digital images which are displayed on a screen, and more particularly to screen displays for a computer or television screen.
2. Description of the Prior Art
In general, the displaying of computer generated graphics on a low-resolution television screen with interlaced refresh has always presented major technical difficulties without achieving genuinely satisfactory quality for users by reason of a flicker effect. On a television screen of standard type, the refreshing of the lines is performed in an interlaced manner. Stated otherwise, the lines of odd rank are refreshed firstly and the lines of even rank subsequently and so on and so forth. If two consecutive lines exhibit very different brightness levels, the human eye of the user will perceive locally a flicker at a frequency of 50 or 60 hertz according to the television standard adopted. This flicker effect is relatively tiresome and in any event very detrimental to the image quality perceived by the user. In actual fact, it turns out that computer generated images such as graphics, windows or sub-windows typically exhibit strong contrasts from one line to another.
At present, the portable computer and television markets are about to merge, under the driving effect of the development of the Internet and of interactive television which requires associated technologies. It is therefore important to be able to display images with strong contrasts from one line to another such as the pages broadcast by the Internet network, on a standard television screen with visual comfort which is acceptable to the user.
The systems used hitherto to suppress or limit this flicker effect are often referred to as flicker filters. Since the flicker effect is due to the contrast between two consecutive lines, stated otherwise to high frequencies on a vertical column of the image, the basic anti-flicker filter systems implement a low-pass vertical digital filtering. After the filtering, two consecutive lines are closer together in terms of color and the flicker effect is diminished.
The effectiveness of a digital filter is tightly bound to the number of points taken into account. This type of filtering consists in fact in replacing a point or pixel by the average of the neighboring points and the larger the number of points to which the average pertains, the more effective is the filtering. This has an important influence on the slope of the transition between the passing part of the filter and the blocked or filtered part. In most graphics architectures, the data relating to the color of a point or of a pixel are read from a buffer memory according to a horizontal scanning order, this requiring the implementation of a number of line memories equal to n−1 for a filter with n steps, this translating into a very high cost of the line memories whose capacity must be large. These line memories are so expensive because they require large areas of silicon, because the anti-flicker filters are generally three-step, that is to say with storage of two lines, this translating into mediocre filtering performance. In point of fact, the filtering takes place during the steps of displaying the image, this requiring high throughput performance even if the filtering is mediocre.
Conventionally, an ideal filter makes it possible to completely suppress the flicker effect due to high frequencies, whilst preserving the low-frequency image details. Real filters are a compromise between flicker reduction and preservation of image precision. Either the entire image seems to be relatively stable but is scrambled on account of the filter, or the entire image is richer in details but is at risk of flickering. The user can be allowed to adjust the filtering according to the compromise which he deems best.
Accordingly, there exists a need for overcoming the disadvantages of the prior art as discussed above.

Anti-flicker filtering process and system


A printer has a paper feed roller and a pressure roller on the upstream side of a platen in the paper feed direction. These rollers nip the continuous paper at a nipping position. When the pressure roller bends down due to pressure from the paper feed roller, the pressure roller moves on a curved path centered on a pivot point of a paper pressing lever. The nipping position of the continuous paper therefore follows the downward movement of the paper feed roller and moves to the side away from the platen along the outside surface of the paper feed roller. The slope θ of the tangent to the nipping position therefore changes, the leading end of the continuous paper conveyed to the platen side rises, and slack in the continuous paper is removed.

1. Technical Field
The present disclosure relates to a printer that conveys the recording medium toward a platen using a paper feed mechanism including a paper feed roller and a pressure roller.
2. Related Art
The paper feed roller can be deflected by the pressure from the pressure roller in a printer that has a paper feed roller and a pressure roller on the upstream side of the platen in the paper feed direction. For example, when the conveyance path is wide and the pressure of the pressure roller is increased to increase the media conveyance force, deflection of the paper feed roller increases. In this event, the middle of the width of the recording medium that is pressed by the paper feed roller also bends and sags greatly. When the recording medium is fed to the platen while thus sagging, the middle of the width of the recording medium may catch on the platen and a paper jam may occur in front of (on the upstream side of) the platen.
A paper feed mechanism that conveys the recording medium while the paper feed roller is in a deflected state is disclosed in JP-A-2009-202978. The image reading device (scanner) taught in JP-A-2009-202978 causes the drive roller (paper feed roller) to bend to the downstream side in the conveyance direction. The left and right ends of the drive roller therefore slope from the ends in toward the center, and the paper can be conveyed without being wrinkled. Because the relative positions of the drive roller and driven roller (pressure roller) are thus offset in the paper conveyance direction at the center of the drive roller, the paper nipping position in the center of the drive roller moves down from the nipping position at the left and right ends of the drive roller. In JP-A-2009-202978, the driven roller is moved downstream in the conveyance direction according to the amount of deflection across the drive roller. As a result, the difference in the height of the nipping positions at the left and right ends of the drive roller and the nipping position in the middle of the drive roller is corrected, and downward deflection of the middle of the width of the paper is prevented. The leading end of the paper can therefore be prevented from catching on the image scanning unit.
The device taught in JP-A-2009-202978 eliminates variation in the nipping position resulting from the drive roller (paper feed roller) bending to the downstream side in the media conveyance direction, and thereby eliminates sagging in the paper, but does not align the height of the nipping positions when parts of the drive roller move up or down, and does not correct sagging in the paper caused by pressure from the driven roller causing the drive roller to bend to the downstream side. Furthermore, the height of the nipping position will change with deformation of the driven roller by simply moving the driven roller in the conveyance direction because the driven roller located in the middle of the drive roller is made from a flexible material, but if the driven roller is a roller that does not change shape, aligning the height of the nipping positions with this simple operation is difficult.


Disclosed herein is a suppressor using one ion-exchange tube which has an inner diameter close to that of a tube connected to a separation column and which is constituted by an ion-exchange membrane. The ion-exchange tube is folded or wound more than once in a plane into a sheet form to provide an ion-exchange tube sheet through which an eluate from a separation column flows. The ion-exchange tube sheet is accommodated in a container. The container provides a regenerant flow channel so that a regenerant is allowed to flow on both sides of the ion-exchange tube sheet.

1. Field of the Invention
The present invention relates to a suppressor for suppressing the background electrical conductivity of an eluate from a separation column of an ion chromatograph or for removing nontarget ions from a sample and an ion chromatograph for separation and analysis of inorganic ions or organic ions contained in a sample solution as one example of an analyzer utilizing such a suppressor.
2. Description of the Related Art
In an ion chromatograph, a sample is introduced into a separation column to separate it into component ions, and then the component ions are detected by measuring the electrical conductivity of an eluate from the separation column in an electrical conductivity measurement cell. In order to achieve high-sensitive measurement, a suppressor is provided between the separation column and the detector. The suppressor removes nontarget ions contained in an eluate from the separation column to reduce the electrical conductivity of the eluate.
A suppressor is used also in a sample pretreatment process to remove nontarget ions from a sample solution.
In a suppressor, ion exchange is performed to remove nontarget ions. Therefore, as a suppressor, one utilizing an ion-exchange column filled with an ion-exchange resin or one utilizing a planar ion-exchange membrane is used. In the case of an ion-exchange column-type suppressor, nontarget ions are removed through ion exchange by allowing a sample solution to pass through a column filled with an ion-exchange resin.
The ion-exchange column needs to be filled with a large amount of ion-exchange resin not only to increase its ion-exchange capacity but also to maintain its ion-exchange ability for a long period of time. However, filling the ion-exchange column with a large amount of ion-exchange resin leads to a larger inner diameter of the ion-exchange column than that of a tube connected to a separation column. This causes broadening of peak segments (bands), separated by the separation column, in the suppressor.
On the other hand, an ion-exchange membrane-type suppressor has two flow channels opposed to each other with an ion-exchange membrane being interposed between them. In the ion-exchange membrane-type suppressor, a sample solution is allowed to flow through one of the flow channels to remove nontarget ions through ion exchange using the ion-exchange membrane, and a regenerant is allowed to flow through the other flow channel to regenerate the ion-exchange membrane.
In the case of the ion-exchange membrane-type suppressor, its flow channel size can be made smaller as compared to the ion-exchange column-type suppressor. However, the flow channel of the ion-exchange membrane-type suppressor is rectangular in cross section, which changes flow conditions. Also in this case, broadening of peak segments occurs in the suppressor.
As a method for suppressing broadening of peak segments in a suppressor, one using an ion-exchange tube constituted by an ion-exchange membrane has been proposed (see U.S. Pat. No. 4,486,312). According to this method, an eluate from a separation column is allowed to flow inside the ion-exchange tube to perform ion exchange inside the tube to remove nontarget ions, and a regenerant is allowed to flow outside the ion-exchange tube to regenerate the ion-exchange membrane outside the tube. In this case, the inner diameter of the ion-exchange tube is made close to that of a tube connected to a separation column. This makes it possible to suppress broadening of peak segments in a suppressor.
The ion-exchange tube needs to be fixed in some way. For example, in the case of the method proposed in Patent Document 1, the tube is wound around a cylindrical core in the form of a coil, and a regenerant is allowed to flow along the wall of the coil. However, the winding of the tube around a core inevitably leads to an increase in the size of a suppressor. Further, the winding of the tube around a support such as a core makes it impossible to bring a regenerant into contact with the surface of the tube located on the support side. This reduces the regeneration efficiency of the ion-exchange membrane by a regenerant, and thus, ion-exchange performance is reduced.

Suppressor utilizing micro ion exchange tube and ion chromatograph utilizing the same


An apparatus for filling a container with a liquid to a predetermined weight which utilizes a scale which generates a control signal which is based on the weight of liquid within the container, a control valve such as a ball valve having a valve element which permits a selectively variable flow rate through the valve, an actuator which is operatively connected to the control valve to vary the position of the valve element and thereby vary the flow rate, a valve positioner to control the operation of the actuator/valve in response to a calculated positioning signal which is related to the control signal and which is generated by an interface arrangement operatively connected to the scale and the positioner. The apparatus further includes a conduit assembly for introducing liquid into the container, the filling assembly including a generally hook-shaped filling lance which is pivotally mounted for rotation about a generally horizontal axis and which can be moved to a liquid discharge position wherein liquid discharged therefrom is directed generally downwardly thereby permitting the filling of foaming liquids without the necessity for subsurface filling. There is also included a fume disposal assembly and a drip collection assembly for the lance being contained within the fume disposal assembly, the drip collection assembly serving to catch any drops of liquid from the lance.

The present invention relates to an apparatus for filling containers with a predetermined weight of liquid and, more particularly, to such an apparatus employing an improved filling lance and interfacing arrangement wherein the liquid is introduced into the container at a rate based on the weight of the liquid already in the container and a flow control equation or program.
The filling of containers with a liquid to a predetermined or desired weight is generally carried out, depending upon the type of liquid, in one of two fill cycles: in the first type of fill cycle, which can be described as "fast-slow-off," the liquid is initially introduced into the container at a relatively high filling rate until a predetermined weight of liquid has been introduced into the container at which point the remaining portion of liquid is admitted at a second, slower fill rate. The first, faster filling rate is known in the art as "fast fill" while the second, slower filling rate has been termed "dribble fill." When the desired weight of liquid has been introduced into the container, the dribble fill is terminated, completing the cycle.
The second type of fill cycle can be termed "slow-fastslow-off." This type of fill cycle is commonly employed with liquids such as detergents or other liquids which easily foam such that if the liquid were initially introduced at a high fill rate into an empty container, the foaming liquid would be forced out of the fill opening of the container resulting in a messy and hazardous work environment. A particularly hazardous environment can exist in the case where the liquid is of a type which not only foams but which also may be quite toxic, such as an insecticide, herbicide or the like. To accommodate such foaming liquids, and for other reasons, it is common to use what is known as "subsurface fill" wherein the conduit or filling lance is inserted into the container for a distance such that the emission end of the conduit or lance is disposed just above the bottom of the container. The liquid is then introduced into the container at a dribble fill rate until a level of liquid is reached in the container such that the emission end of the lance is below the surface of the liquid. At this point, the liquid may then be introduced at a fast fill rate until a predetermined weight of liquid is reached. At this point, dribble flow rate is again used to bring the volume of liquid introduced into the container to the desired fill rate. At this point, the fill cycle is complete and the flow of liquid is stopped.
Examples of prior art apparatus for carrying out liquid filling of containers include U.S. Pat. Nos. 4,211,263 and 4,337,802, both of which to Applicant's knowledge represent the closest prior art.
There are numerous problems associated with the prior art apparatus such as described in the aforementioned patents. In order to carry out either of the two fill cycles described above, the prior art systems have either employed two valves, one for fast fill and one for dribble fill, or, alternatively, have used a single valve with three positions, i.e. fully closed, fully open and selectable intermediate. Filling apparatus employing such valve assemblies are bulky, complicated to construct and maintain and require extensive logic circuitry if the apparatus is to be used for the automatic filling of containers. Moreover, because the prior art systems require a dribble fill mode in order to prevent overshooting the desired weight of liquid in the container, there is a necessary loss of efficiency because of the time consuming dribble fill. Another problem with such prior art systems is that because for accuracy with optimum efficiency, they must fill the bulk of the liquid in a fast fill mode and then switch to a second slower, dribble fill mode, there is a necessity to have a fast valve closure lest there be an inadvertent overfill. Over and above the added expense of providing such a fast close valve system, such systems inherently produce a water hammer effect in the liquid feed line leading to the fill apparatus. As is well known to those skilled in the art, the water hammer effect is undesirable as it puts unnecessary stresses on flow lines, valves and fittings. Moreover, there is always the possibility of a line or fitting rupture caused by the instantaneous pressure build up with the result that a serious spill of liquid can occur.
The prior systems such as disclosed in the aforementioned U.S. patents present serious disadvantages when subsurface filling is necessary. In prior art subsurface fill operations, the filling lance is normally withdrawn from the container at a rate which maintains the end of the lance below the liquid surface in the container. Operator withdrawal of the lance results in some inaccuracy in the final fill weight since there is a tendency to withdraw the lance slower than necessary to avoid breaking the surface of the liquid. On the other hand, in systems wherein the movement of the lance is automatically controlled at the various stages in the filling process, such as the withdrawal during a subsurface fill operation, it requires expensive logic circuitry, limit switches and associated equipment all of which is expensive to manufacture and relatively complicated to maintain. Additionally, such automated systems wherein the lance is automatically withdrawn require a movable carriage mounted on a suitable track system which will move the lance, the valve and the peripheral equipment in a vertical reciprocating fashion so that the lance may be inserted and withdrawn from the fill opening of the container. It will be appreciated that such an apparatus wherein an elongate fill lance must be moved vertically so as to clear the top of the container will be bulky, and require a large amount of overhead space.
Prior art filling systems have also generally required movable, programmable drip pan assemblies to catch liquid drops from the withdrawn lance to avoid either spillage onto the container and surroundings or overfill of the container, elaborate fume hood assemblies to control noxious vapors, and wiper rings, in the case of subsurface filling, to remove excess liquid from the exterior surface of the lance as it is withdrawn from the filling container. Lastly, to ensure accuracy in the filling of the containers, more modern prior art devices have utilized a foot valve assesmbly to prevent liquid which is contained in the filling lance from emptying into the container after the main control valve has been closed.

Apparatus for liquid filling of containers


A radio apparatus communicates with a plurality of terminal apparatuses by using a packet signal composed of at least one stream. A control unit divides a certain period into a plurality of partial periods and assigns respectively the plurality of partial periods to the plurality of terminal apparatuses by associating the periods with the terminal apparatuses. The control unit also generates a packet signal for use in control and packet signals for use in inquiry. In so doing, the control unit generates the inquiry packet signals for the plurality of respective terminal apparatuses, as a single packet signal. A baseband processing unit and other units transmit the control packet signal and then transmit the inquiry packet signals, and receive packet signals, containing inquiry results, from the plurality of respective terminal apparatuses.

1. Field of the Invention
The present invention relates to a communication technology, and it particularly relates to a method for transmitting a packet signal composed of multiple subcarriers, and a radio apparatus and a communication system utilizing the same.
2. Description of the Related Art
An OFDM (Orthogonal Frequency Division Multiplexing) modulation scheme is one of multicarrier communication schemes that can realize the high-speed data transmission and are robust in the multipath environment. This OFDM modulation schexme has been applied to the wireless LAN (Local Area Network) standards such as IEEE 802.11 a/g and HIPERLAN/2. The packet signals in such a wireless LAN are generally transferred via a time-varying channel environment and are also subject to the effect of frequency selective fading. Hence, a receiving apparatus generally carries out the channel estimation dynamically.
In order for the receiving apparatus to carry out the channel estimation, two kinds of known signals are provided within a packet signal. One is the known signal, provided for all carries in the beginning of the burst signal, which is the so-called preamble or training signal. The other one is the known signal, provided for part of carriers in the data area of the packet signal, which is the so-called pilot signal (See Reference (1) in the following Related Art List, for instance).
Related Art List
    (1) Sinem Coleri, Mustafa Ergen, Anuj Puri and Ahmad Bahai, "Channel Estimation Techniques Based on Pilot Arrangement in OFDM Systems", IEEE Transactions on broadcasting, vol. 48, No. 3, pp. 223-229, Sept. 2002.
In wireless communications, adaptive array antenna technology is one of the technologies to realize the effective utilization of frequency resources. In adaptive array antenna technology, the directional patterns of antennas are controlled by controlling the amplitude and phase of signals, to be processed, in a plurality of antennas, respectively. One of techniques to realize higher data transmission rates by using such an adaptive array antenna technology is the MIMO (Multiple-Input Multiple-Output) system. In this MIMO system, a transmitting apparatus and a receiving apparatus are each equipped with a plurality of antennas, and packet signals to be transmitted in parallel are set (hereinafter, each of data and the like to be transmitted in parallel in a packet signal is called "stream"). That is, streams up to the maximum number of antennas are set for the communications between the transmitting apparatus and the receiving apparatus so as to improve the data transmission rates.
Moreover, combining this MIMO system with the OFDM modulation scheme results in a higher data transmission rate. In the MIMO system, the data rate can also be adjusted by increasing or decreasing the number of antennas to be used for data communications. Furthermore, the data rate can be adjusted in greater detail by applying the adaptive modulation to the MIMO system. To perform such an adjustment of data rates more reliably, the transmitting apparatus should acquire from the receiving apparatus the information on data rates suited for the radio channel between the transmitting apparatus and the receiving apparatus (hereinafter this information will be referred to as "rate information"). To raise the accuracy of the rate information like this, it is desired that the channel characteristics between a plurality of antennas in the transmitting apparatus and a plurality of antennas contained in the receiving apparatus, respectively, be acquired by the receiving apparatus.
To improve the accuracy of rate information in the above-mentioned requirements, it is necessary that the channel characteristics be acquired with high accuracy. To improve the accuracy in the acquisition of channel characteristics, the transmitting apparatus or the receiving apparatus transmits from all of antennas the known signals for use in channel estimation. Hereinafter, the known signals, for use in channel estimation, assigned to a plurality of streams will be referred to as "training signals" independently of the number of streams to which data are assigned. For example, even though data are assigned to two streams, the training signals are assigned to four streams.
Under these circumstances, the inventor of the present invention came to recognize the following problems to be solved. When the training signals are transmitted, the number of streams containing known signals for use in channel estimation (hereinafter referred to as "channel estimation known signals") differs from that containing data. A known signal for setting AGC (Automatic Gain Control), hereinafter referred to as "AGC known signal", at the receiving side is assigned anterior to the channel estimation known signals. When an AGC known signal is assigned only to a stream where data is assigned, part of the channel estimation known signals is received, in a state where the AGC known signal has not been received, anterior thereto. In particular, when the strength of AGC known signal gets larger at the receiving side, the gain of AGC is set to a value which is large to a certain degree. In so doing, when the strength of channel estimation known signal of a stream where the AGC known signal is not assigned is larger, there is a strong possibility that said channel estimation known signal may be amplified to such a degree that distortion is caused by AGC. As a result thereof, the error in channel estimation based on said channel estimation known signal becomes large.
On the other hand, when an AGC known signal is assigned to a stream where a channel estimation known signal is assigned, the number of streams to which the AGC known signal is assigned differs from the number of streams to which data is assigned. Hence, there is a possibility that the gain set by the AGC known signal is not suitable for the demodulation of data. As a result, the demodulated data are subject to errors. In particular, if the difference between the number of streams to which the channel estimation known signals are assigned and that to which the data are assigned gets larger, these problems to be solved will become more important issues.
When the base station apparatus multiplexes the communication with a plurality of terminal apparatuses, CSMA (Carrier Sense Multiple Access) is carried out. For the purpose of improving the transmission efficiency, one basestation apparatus occupies a frequency band in a predetermined period of time so as to continuously transmit a plurality of packet signals. That is, the base station apparatus specifies, in partial periods of time, the timing at which the signals are to be transmitted to a plurality of terminal apparatuses (hereinafter referred to as "transmit timing") and the timing at which the signals from a plurality of terminal-apparatuses are to be received (hereinafter referred to as "receive timing"). Then the base station apparatus informs respectively the plurality of terminal apparatuses of said specification, and each of the plurality of terminal apparatuses carries out a processing in accordance with said specification (hereinafter, such a processing will be referred to as "assignment mode"). Here it is assumed that after a plurality of transmit timings for the plurality of terminals are specified, a plurality of transmit timings are specified consecutively. A terminal apparatus receives a signal at the specified transmit timing. Even if the aforementioned training signals are transmitted under such circumstances, it is still desirable that the degradation of transmission efficiency be prevented.

Communication method for transmitting multiple packet signals, and radio apparatus and communication system using the same


Engine torque is managed, particularly during a gear change, so as to improve comfort and reduce wear of the engine and components associated therewith. A transmission control module is adapted to determine start and end times for torque management on the basis of a plurality of look-up tables stored in memory which are accessed via one or more engine operating parameters determined from a plurality of sensors. The contents of the look-up tables are determined experimentally to give the most appropriate start and end times for the given conditions, and not on the basis of any mathematical formula.

The present invention relates to a method for controlling engine torque for use, for example, during a gear changing operation in a vehicle.
It is known, particularly for automatic and semi-automatic transmissions, to control the engine torque when the transmission is changing from one gear to another in order to improve the comfort for the driver and passengers of the vehicle.
One example of a method of controlling engine torque in an automatic transmission is shown in EP-A-0,355,070, in which the engine torque is reduced during a period of the gear change. The start and end times of this control period are determined from mathematical formulae which are based on the engine speed at particular points in the gear change. A problem with this type of torque control is that the mathematical formulae do not give the best results over the whole range of gear changes.

Control method for managing engine torque


The present invention is directed to providing an accumulator for pulsation absorption on a feeding passage between a hydraulic pressure generating device and hydraulic pressure booster equipment, and to provide a restriction on a section of the feeding passage between the accumulator and the hydraulic pressure generating device. As the result, the pulsation caused by a pump is reduced by the restriction, and the pulsation thus reduced is absorbed by the accumulator. Therefore, pulsation is effectively decreased by the restriction and the accumulator, and the pulsation transmitted to the hydraulic pressure booster equipment is quite small.

The present invention relates to a hydraulic pressure booster system, in which a hydraulic pressure booster equipment such as brake booster boosts the input to the predetermined value and outputs it by the pressurized operating fluid from hydraulic pressure generating means.
The hydraulic pressure booster system is used in various equipment and devices such as brake booster system in brake unit of automobile or clutch booster system in power transmission equipment, and it provides big operating force by small actuating force.
In the hydraulic pressure booster system of conventional type, hydraulic pressure generating means is provided for generating hydraulic pressure because hydraulic pressure is utilized, and a pump consisting of piston pump is normally used as such hydraulic pressure generating means.
However, in case such piston pump is used, pulsation occurs in the hydraulic pressure circuit by reciprocal movement of the piston, and this pulsation is transmitted to the hydraulic pressure booster equipment through the hydraulic pressure circuit. For this reason, the noise caused by pump pulsation is generated in the vehicle through the hydraulic pressure booster equipment. Also, because of such pump pulsation, stable operation of the hydraulic pressure booster equipment is hindered.
To solve the problem, it is proposed that an accumulator to absorb this pulsation is provided on the supply passage to feed the operating fluid. By such accumulator, pump pulsation can be absorbed to some extent.
However, it is difficult by this accumulator for absorbing pulsation in some cases to absorb the pulsation efficiently and adequately, and the transmission of the pulsation to the hydraulic pressure booster equipment cannot be prevented completely.
Even in such case, it is desirable that pulsation can be absorbed as much as possible. To cope with such demand, study has been performed in various ways, and it has been found that, if long flexible hose is furnished before and after the accumulator, the pulsation can be efficiently absorbed even when it is difficult to absorb the pulsation by accumulator only. In such case, in order to perfectly obtain the pulsation absorbing effect by flexible hose, it is necessary to sufficiently extend the length of the hose.
Incidentally, the hydraulic pressure booster equipment such as hydraulic brake booster or hydraulic clutch booster equipment must be designed in compact form to suit the place or the space where it is furnished. Therefore, the length of the flexible hose as described above must also be limited to such length as to match the layout of the system.
Thus, the demands must be fulfilled, on the one hand to extend the length of the hose as long as possible in order to obtain the better pulsation absorbing effect, and on the other hand, to shorten the length of the hose to meet the requirements limited by the layout of the system.


Compounds of the formula ##STR1## wherein the broken line represents an optional double bond; X is O, S, CH.sub.2 or CH.sub.2 CH.sub.2, and the pharmaceutically acceptable salts thereof. The compounds are useful in treating inflammation or other prostaglandin or leukotriene mediated diseases.

The present invention relates to pyrroloquinoline and pyrrolophenothiazine carboxamides and related compounds, methods of preparing such compounds, pharmaceutical compositions comprising such compounds and the use of such compounds in treating inflammation (e.g., arthritis) or other prostaglandin or leukotriene mediated diseases.
Oxindole-carboxamides useful as antiinflammatory agents and analgesics are referred to in U.S. Pat. Nos. 4,556,672, 4,569,942, 4,644,005, 4,678,802, and 4,686,224, and in U.S. Ser. No. 670,697, filed Nov. 13, 1984, and U.S. Ser. No. 821,296, filed Jan. 22, 1986.
U.S. Pat. No. 4,695,571 refers to tricyclic oxindoles as antiinflammatory agents.
United States Patent 4,690,943 refers to 1,3-diacyl-2-oxindoles as antiinflammatory agents and analgesics.
U.S. Pat. No. 4,658,037 and U.S. Ser. No. 670,697, filed Nov. 13, 1984, refer to intermediates for preparing oxindole carboxamides.


Frames of a virtual desktop are encoded using a hybrid approach that combines the strength of software encoding by a central processing unit (CPU) and hardware encoding by a graphics processing unit (GPU). A method of encoding frame data of one or more virtual desktops in hardware and in software and transmitting the encoded frame data to one or more client devices, includes the steps of encoding a first portion of the frame data in the GPU to generate a first encoded frame data, encoding a second portion of the frame data in software, i.e., programmed CPU, during encoding of the first portion, to generate a second encoded frame data, and transmitting the first encoded frame data and the second encoded frame data from a host computer of the one or more virtual desktops to the one or more client devices as separate video streams.

Desktop virtualization is software technology that separates the desktop environment and associated application software from a client computing device that is used to access it. Virtual desktop infrastructure (VDI) implements desktop virtualization using virtual machines (VMs). In VDI, the desktop environment and associated application software are executed in a VM which runs on a remote host computer. The virtual desktop is generated at the host computer and display frames of the virtual desktop are transmitted from the host computer to the client computing device so that they can be displayed at the client computing device. User inputs are made at the client computing device and such inputs are transmitted to the host computer for processing by the host computer.
Remote display protocols for efficiently delivering the frames of the virtual desktop from the host computer to client computing devices have been developed. PC over IP (PCoIP) is one such remote display protocol. According to PCoIP, the frames are encoded at the host computer, typically using a central processing unit (CPU) of the host computer, to capture only regions of the virtual desktop that have changed, and the encoded frame data is transmitted to the client computing device as a pixel stream.
VMware Blast® is another remote display protocol. The VMware Blast encodes the frames according to the H.264 video encoding standard and the encoded data is transmitted to the client computing device as a standard video stream instead of a pixel stream. The VMware Blast protocol can be implemented on either the CPU or a graphics processing unit (GPU) of the host computer.

Hybrid software and GPU encoding for UI remoting