An optical scanning device has: a first optical system for converting a flux of light that has been emitted from a light source into another flux of light; a second optical system for focusing the flux of light that has been converted by the first optical system as a linear image elongated in the main scanning direction; deflecting means for reflecting and deflecting the flux of light that has left the second optical system; and a third optical system for guiding the flux of light that has been deflected by the deflecting means onto a surface to be scanned. The flux of light emitted from the light source is entered into a deflection surface of the deflecting means at a limited angle in the sub-scanning section and, by setting parameters in a manner that satisfies a given condition, the pitch unevenness can effectively be reduced in the optical systems.

1. Field of the Invention
The present invention relates to an optical scanning device and an image forming apparatus using the same. More specifically, the invention relates to reduction in pitch unevenness in an optical scanning device where a flux of light emitted from light source means enters a deflection surface of deflecting means at a given angle in the sub-scanning section and the flux of light reflected and deflected by the deflecting means is applied to a recording medium (photosensitive drum) surface to record image information. The optical scanning device of the present invention is suitable for an image forming apparatus that involves an electrophotographic process, such as a laser beam printer, a digital copying machine, and a multi-function printer.
2. Related Background Art
Various multi-beam optical scanning devices which achieve multi-color by making fluxes of light enter into a common scanning optical system have been proposed in the past. To irradiate surfaces to be scanned with fluxes of light separately in this type of multi-beam optical scanning device, the light fluxes have to be separated after deflected and reflected by a light deflector (e.g., polygon mirror), and if sources of the light fluxes have the same wavelength, spatial separation is necessary. Objective spatial separation is achieved by, for example, making the fluxes of light enter into a deflection surface (reflection surface) of a light deflector from an oblique direction in the sub-scanning section (hereinafter referred to as oblique incidence).
FIGS. 15A and 15B are partial sectional views showing oblique incidence in an optical system of a multi-beam optical scanning device. FIG. 15A shows the main scanning section whereas FIG. 15B shows the sub-scanning section perpendicular to the paper plane of FIG. 15A. Illustrated in FIGS. 15A and 15B are two fluxes of light entered into a deflection surface of a light deflector from opposing directions and the behavior of the light fluxes after they are deflected and reflected by the deflection surface.
In FIGS. 15A and 15B, reference numeral 91 denotes a light deflector, for example, polygon mirror. 92a and 92b denote two oblique incident rays deflected and reflected by the polygon mirror 91. 95 denotes a scanning lens system (fθ lens system) composed of a cylindrical lens 93 and toric lenses 94a and 94b (a two-lens system). The cylindrical lens 93 has a given refractive power only in the main scanning section.
An incidence optical system, which is not shown in FIGS. 15A and 15B, makes two fluxes of light enter obliquely into the polygon mirror 91. In the incidence optical system, two light fluxes are emitted from two light sources (the number of light sources corresponds to the two oblique incident rays 92a and 92b), are converted into parallel pencils of light by a collimator lens, and then form a linear image in the vicinity of a deflection surface 91a of the polygon mirror 91 with the help of a cylindrical lens that has a given refractive power only in the sub-scanning section. This is a measure taken to correct a tilt of the polygon mirror's deflection surface within the sub-scanning section by placing the polygon mirror's deflection surface and a surface to be scanned (photosensitive drum surface) in an optically conjugate relation. In short, the incidence optical system constitutes a deflection surface tilt correction optical system.
The two light fluxes deflected and reflected by the polygon mirror 91 (the oblique incident rays 92a and 92b) are led to given positions on surfaces of photosensitive drums by the scanning lens system 95 through their respective light path-bending mirrors (not shown in the drawings). As the polygon mirror 91 is rotated, the rays draw scanning lines in the axial direction (main scanning direction in which deflection scan with the light fluxes proceeds) and rotation of the photosensitive drums which is synchronized with the rotation of the polygon mirror 91 arranges the scanning lines at regular intervals in the sub-scanning direction perpendicular to the main scanning direction.
In this way, surfaces of two photosensitive drums can simultaneously be scanned. If a scanning optical system is placed on each side of the polygon mirror to share the polygon mirror between the two scanning optical systems, exposure and development can be finished for four colors at once, thus making high-speed, full-color printing possible.
However, the principle of separation of rays through oblique incidence makes variation in distance from a rotation axis to deflection surfaces inevitable due to polygon mirror's manufacture error and the like (the difference is hereinafter referred to as "deflection surface eccentricity"). The deflection surface eccentricity makes the pitch irregular and leads to poor image reproducibility.
Therefore, while a normal scanning optical system only has to deal with pitch unevenness caused by a tilt of a deflection surface of a polygon mirror, an oblique incidence optical system has to solve pitch unevenness caused by deflection surface eccentricity in addition to pitch unevenness caused by a tilt of a deflection surface of a polygon mirror.
Although a multi-beam optical scanning device is taken as an example in the above description of prior art, conventional single-beam optical scanning devices that use oblique incidence also have the same problem.
Prior art has proposed a diversity of optical scanning devices in which pitch unevenness due to deflection surface eccentricity is reduced (see Japanese Patent Application Laid-Open No. H10-327302 and Japanese Patent Application Laid-Open No. 2001-051226, for example).
Japanese Patent Application Laid-Open No. H10-327302 discloses a technique that reduces, in the case of on-axis incidence, pitch unevenness resulting from polygon mirror's deflection surface eccentricity by setting parameters in a manner that limits the pitch unevenness to within ¼ pixel. Japanese Patent Application Laid-Open No. 2001-051226 discloses a technique that reduces, in a system where a flux of light has a given incident angle also in the main scanning section, pitch unevenness resulting from polygon mirror's deflection surface eccentricity by setting parameters in a manner that limits the pitch unevenness to within ⅕ pixel to 1/10 pixel.
Japanese Patent Application Laid-Open No. H10-327302 and No. 2001-051226 both state that pitch unevenness caused by a tilt of the deflection surface can be ignored because of a deflection surface tilt correction system provided. In actuality, however, no deflection surface tilt correction system has ever truly succeeded in correcting the tilt throughout the entire scan region since the deflection surface wobbles as the polygon mirror rotates. Furthermore, the conjugate point could be shifted by error in manufacture, arrangement and the like of an imaging lens and other components, thereby deteriorating further deflection surface tilt and increasing the pitch unevenness.

Optical scanning device and image forming apparatus using the same


This disclosure features methods and compositions for treating diseases of the gastrointestinal tract with IL-10 or an IL-10 agonist.

Interleukin 10 (IL-10) is a key immunoregulator of various types of infection, including but not limited to: Toxoplasma gondii infection (see, e.g., Gazzinelli et al., J. Immunol. 157:798-805, 1996; Wilson et al., J. Neuroimmunol. 165:63-74, 2005; Jankovic et al., J. Exp. Med. 204:273-283, 2007; Roers et al., J. Exp. Med. 200:1289-1297, 2004), Trypansoma cruzi infection (see, e.g., Hunter et al., J. Immunol. 158:3311-3316, 1997; Reed et al., J. Immunol. 153:3135-3140, 1994; Holscher et al., Infect. Immun. 68:4075-4083, 2000), Streptococcus pyogenes infection (see, e.g., Stumhofer et al., Nat. Immunol. 8:1363-1371, 2007), Helicobacter infection (see, e.g., Kullberg et al., J. Exp. Med. 196: 505-515, 2002), Listeria monocytogenes infection (see, e.g., Fleming et al., J. Leukocyte Biol. 66:961-967, 1999), human immunodeficiency virus infection (see, e.g., Ji et al., Int. Immunol. 17:729-736, 2005; Elrefaei et al., J. Immunol. 178:3265-3271, 2007), MCMV infection (see, e.g., Redpath et al., J. Immunol. 162:6701-6707, 1999), and Candida albicans infection (see, e.g., Netea et al., J. Immunol. 172:3712-3718, 2004; and Montagnoli et al., J. Immunol. 169:6298-6308, 2002).
IL-10 was first discovered as a T helper 2 specific cytokine (Fiorentino et al., J. Exp. Med. 170:2081-2095, 1989). However, numerous innate and adaptive immune cells are able to produce and secrete IL-10, such as mast cells, natural killer cells, eosinophils, neutrophils macrophages, regulatory T cells, dendritic cells, B cells (see, e.g., Fillatreau et al., Nat. Immunol. 3:944-950, 2002; Maloy and Powrie, Nat. Immunol. 2:816-822, 2001; Maynard et al., Immunol. Rev. 226:219-233, 2008; Moore et al., Annu. Rev. Immunol. 19:683-765, 2001; and Roncarolo et al., Immunol. Rev. 212: 28-50, 2006).
IL-10 deficient mice develop colitis and colorectal cancer indicating the crucial role of IL-10 in intestinal homeostasis; and has suggested a role of IL-10 in control of gut flora (Kuhn et al., Cell 75:263-274, 1993; Leon et al., Ann. N.Y. Acad. Sci. 856:69-75, 1998; Sellon et al., Infect. Immun. 66:5224-5231, 1998).
IL-10 is an anti-inflammatory cytokine and inhibits the production of an array of inflammatory mediators by STAT3 activation (Murray, Proc. Natl. Acad. Sci. U.S.A. 102(24):8686-8691, 2005; Moore et al., Annu. Rev. Immunol. 19:683-765, 2001; Mosmann, Ad. Immunol. 56:1-16, 1994). Treatment with an IL-10 receptor agonist may therefore provide relief for patients suffering from diseases with extensive and excessive inflammation (Fioranelli, J. Integr. Cardiol. 1:1, 2014).
The gastrointestinal (GI) tract generally provides a therapeutic medium for an individual's body. At times, therapeutic drugs may need to be dispensed to specified locations within the small intestine or large intestine, which is more effective than oral administration of the therapeutic drugs to cure or alleviate the symptoms of some medical conditions. For example, therapeutic drugs dispensed directly within the small intestine would not be contaminated, digested or otherwise compromised in the stomach, and thus allow a higher dose to be delivered at a specific location within the small intestine. However, dispensing therapeutic drugs directly within the small intestine inside a human body (e.g., the cecum, the ascending colon) can be difficult, because a device or mechanism (e.g., special formulation) would be needed to transport a therapeutically effective dose of drug to a desired location within the small intestine and then automatically deliver the therapeutic drug at the desired location. Dispensing therapeutic drugs directly within other locations in the GI tract of the human body can be similarly difficult. Such a device or mechanism also would also need to be operated in a safe manner in that the device or mechanism needs to physically enter the human body.
In sum, there remains a significant unmet medical need for improved treatment regimens for gastrointestinal diseases, such as inflammatory bowel disease (IBD), including a need for regimens which can dispense therapeutics to specific locations within the GI tract, thereby reducing or avoiding the drawbacks of oral or other forms of systemic administration.

Treatment of a disease of the gastrointestinal tract with IL-10 or an IL-10 agonist


Metal carbide supported polycrystalline diamond (PCD) compacts having improved abrasion/impact resistance properties and a method for making the same under high temperature/high pressure (HT/HP) processing conditions. The PCD compact is characterized as having a mixture of submicron sized diamond particles and large sized diamond particles.

The present invention relates to supported polycrystalline diamond (PCD) compacts made under high temperature/high pressure (HT/HP) processing conditions, and more particularly to supported PCD compacts having improved diamond to diamond particle bonding and increased diamond density in PCD compacts.
A compact may be characterized generally as an integrally-bonded structure formed of a sintered, polycrystalline mass of abrasive particles, such as diamond or CBN. Although such compacts may be self-bonded without the aid of a bonding matrix or second phase, it generally is preferred, as is discussed in U.S. Pat. Nos. 4,063,909 and 4,601,423, to employ a suitable bonding matrix which usually is a metal such as cobalt, iron, nickel, platinum, titanium, chromium, tantalum, or an alloy or mixture thereof. The bonding matrix, which is provided at from about 10% to 30% by volume, additionally may contain a recrystallization or growth catalyst such as aluminum for CBN or cobalt for diamond.
For many applications, it is preferred that the compact is supported by bonding it to substrate material to form a laminate or supported compact arrangement Typically, the substrate material is provided as a cemented metal carbide which comprises, for example, tungsten, titanium, or tantalum carbide particles, or a mixture thereof, which are bonded together with a binder of between about 6% to about 25% by weight of a metal such as cobalt, nickel, or iron, or a mixture or alloy thereof. As is shown, for example, in U.S. Pat. Nos. 3,381,428; 3,852,078; and 3,876,751, compacts and supported compacts have found acceptance in a variety of applications as parts or blanks for cutting and dressing tools, as drill bits, and as wear parts or surfaces.
The basic HT/HP method for manufacturing the polycrystalline compacts and supported compacts of the type herein involved entails the placing of an unsintered mass of abrasive, crystalline particles, such as diamond or CBN, or a mixture thereof, within a protectively shielded metal enclosure which is disposed within the reaction cell of a HT/HP apparatus of a type described further in U.S. Pat. Nos. 2,947,611; 2,941,241; 2,941,248; 3,609,818; 3,767,371; 4,289,503; 4,673,414; and 4,954,139. Additionally placed in the enclosure with the abrasive particles may be a metal catalyst if the sintering of diamond particles is contemplated, as well as a pre-formed mass of a cemented metal carbide for supporting the abrasive particles and to thereby form a supported compact therewith. The contents of the cell then are subjected to processing conditions selected as sufficient to effect intercrystalline bonding between adjacent grains of the abrasive particles and, optionally, the joining of the sintered particles to the cemented metal carbide support. Such processing conditions generally involve the imposition for about 3 to 120 minutes of a temperature of at least 1300.degree. C. and a pressure of at least 20 kbar.
As to the sintering of polycrystalline diamond compacts or supported compacts, the catalyst metal may be provided in a pre-consolidated form disposed adjacent the crystal particles. For example, the metal catalyst may be configured as an annulus into which is received a cylinder of abrasive crystal particles, or as a disc which is disposed above or below the crystalline mass. Alternatively, the metal catalyst, or solvent as it is also known, may be provided in a powdered form and intermixed with the abrasive crystalline particles, or as a cemented metal carbide or carbide molding powder which may be cold pressed in to shape and wherein the cementing agent is provided as a catalyst or solvent for diamond recrystallization or growth. Typically, the metal catalyst or solvent is selected from cobalt, iron, or nickel, or an alloy or mixture thereof, but other metals such as ruthenium, rhodium, palladium, chromium, manganese, tantalum, and alloys and mixtures thereof also may be employed.
Under the specified HT/HP conditions, the metal catalyst, in whatever form provided, is caused to penetrate or "sweep" into the abrasive layer by means of either diffusion or capillary action, and is thereby made available as a catalyst or solvent for recrystallization or crystal intergrowth. The HT/HP conditions, which operate in the diamond stable thermodynamic region above the equilibrium between diamond and graphite phases, effect a compaction of the abrasive crystal particles which is characterized by intercrystalline diamond-to-diamond bonding wherein parts of each crystalline lattice are shared between adjacent crystal grains. Preferably, the diamond concentration in the compact or in the abrasive table of the supported compact is at least about 70% by volume. Methods for making diamond compacts and supported compacts are more fully described in U.S. Pat. Nos. 3,141,746; 3,745,623; 3,609,818; 3,850,591; 4,394,170; 4,403,015; 4,797,326; and 4,954,139.
As to polycrystalline CBN compacts and supported compacts, such compacts and supported compacts are manufactured in general accordance with the methods suitable for diamond compacts. However, in the formation of CBN compacts via the previously described "sweep-through" method, the metal which is swept through the crystalline mass need not necessarily be a catalyst or solvent for CBN recrystallization. Accordingly, a polycrystalline mass of CBN may be joined to a cobalt-cemented tungsten carbide substrate by the sweep through of the cobalt from the substrate and into the interstices of the crystalline mass notwithstanding that cobalt is not a catalyst or solvent for the recrystallization of CBN. Rather, the interstitial cobalt functions as a binder between the polycrystalline CBN compact and the cemented tungsten carbide substrate.
As it was for diamond, the HT/HP sintering process for CBN is effected under conditions in which CBN is the thermodynamically stable phase. It is speculated that under these conditions, intercrystalline bonding between adjacent crystal grains also is effected. The CBN concentration in the compact or in the abrasive table of the supported compact is preferably at least about 50% by volume. Methods for making CBN compacts and supported compacts are more fully described in U.S. Pat. Nos. 2,947,617; 3,136,615; 3,233,988; 3,743,489; 3,745,623; 3,831,428; 3,918,219; 4,188,194; 4,289,503; 4,673,414; 4,797,326; and 4,954,139. Exemplary CBN compacts are disclosed in U.S. Pat. No. 3,767,371 to contain greater than about 70% by volume of CBN and less than about 30% by volume of a binder metal such as cobalt Such compacts are manufactured commercially by the General Electric Company under the name BZN 6000.RTM..
As is described in U.S. Pat. No. 4,334,928, yet another form of a polycrystalline compact, which form need not necessarily exhibit direct or intercrystalline bonding, involves a polycrystalline mass of diamond or CBN particles having a second phase of a metal or alloy, a ceramic, or a mixture thereof. The second material phase is seen to function as a bonding agent for the abrasive crystal particles. Polycrystalline diamond and polycrystalline CBN compacts containing a second phase of a cemented carbide are exemplary of these "conjoint" or "composite" polycrystalline abrasive compacts. Such compacts may be considered to be "thermally-stable" as compared to metal-containing compacts as having service temperatures above about 700.degree. C. Compacts as those described in U.S. Pat. No. 4,334,928 to comprise 80 to 10% by volume of CBN and 20 to 90% by volume of a nitride binder such as titanium nitride also may be considered exemplary of a thermally-stable material. Such CBN-TiN compacts are manufactured commercially by the General Electric company under the name BZN 8100.RTM..
With respect to supported compacts, it is speculated, as is detailed in U.S. Pat. No. 4,797,326, that the bonding of the support to the polycrystalline abrasive mass involves a physical component in addition to a chemical component which develops at the bondline if the materials forming the respective layers are interactive. The physical component of bonding is seen to develop from the relatively lower CTE of the polycrystalline abrasive layer as compared to the cemented metal support layer. That is, upon the cooling of the supported compact blank from the HT/HP processing conditions to ambient conditions, it has been observed that the support layer retains residual tensile stresses which, in turn, exert a radial compressive loading on the polycrystalline compact supported thereon. This loading maintains the polycrystalline compact in compression which thereby improves fracture toughness, impact, and shear strength properties of the laminate.
In the commercial production of supported compacts it is common for the product or blank which is recovered from the reaction cell of the HT/HP apparatus to be subjected to a variety or finishing operations which include cutting, such as by electrode discharge machining or with lasers, milling, and especially grinding to remove any adherent shield metal from the outer surfaces of the compact Such finishing operations additionally are employed to machine the compact into a cylindrical shape or the like which meets product specifications as to diamond or CBN abrasive table thickness and/or carbide support thickness. Especially with respect to diamond and CBN supported compacts, a substantially uniform abrasive layer thickness is desirable since the abrasive tables on the blanks are often machined by the user into final products having somewhat elaborate configurations, e.g., sawtoothed wedges, which are tailored to fit particular applications. It will be appreciated, however, that during such finishing operations, the temperature of the blank, which previously had been exposed to a thermal cycle during its HT/HP processing and cooling to room temperature, can be elevated due to the thermal effects of grinding or cutting operations. Moreover, the blank or product finished therefrom may be mounted onto the steel shank of a variety of cutting or drilling tools using braze or solder techniques requiring temperatures of from about 750.degree. to about 800.degree. C. to melt the filler alloy. This again subjects the compacts and supports to thermal gradients and stresses. During each of the thermal cyclings of the supported blank, the carbide support, owing to its relatively higher coefficient of thermal expansion (CTE), will have expanded to a greater extent than the abrasive compact supported thereon. Upon heating and cooling, the stresses generated are relieved principally through the deformation of the abrasive table which may result in its stress cracking and in its delamination from its support.
To improve the bond strength at the interface between, particularly, PCD compacts and their cemented metal carbide supports, proposal have been made to interpose an intermediate layer between the PCD and carbide layers. As is detailed in U.S. Pat. Nos. 4,403,015 and 5,037,704, the intermediate layer is provided to contain less than about 70% by volume of CBN and a balance of a nitride such as TiN, and is sintered directly between the PCD and carbide layers using the traditional HT/HP method. The interposition of a CBN-TiN bonding layer has been observed to prevent the influx or "sweep" of the cobalt binder from the carbide layer to the PCD layer wherein it would have otherwise catalyzed the back-conversion of diamond to graphite hereby weakening the interface between the PCD and carbide layers.
As to supported PCD compacts, it is known in the art to use various size feed powder in forming sintered diamond compacts. However, using fine diamond particles alone usually causes unacceptable reduction of the high abrasion resistance. Using large diamond particles alone results in reduction of diamond density and diamond to diamond bonding. Since supported PCD compacts heretofore known in the art have garnered wide acceptance for use in cutting and dressing tools, drill bits, and the like, it will be appreciated that further improvements in the strength and impact properties of such materials would be well-received by industry. Especially desired would be supported diamond compacts having improved thermal stability, abrasion and wear resistance and impact resistance which would expand the applications for such material by enhancing their machinability, performance, and wear properties. Thus, there has been and heretofore has remained a need for supported PCD compacts having improved physical properties.

Abrasive compact with improved properties


The present invention provides methods of reducing the virucidal activity of a composition comprising a PCV-2 antigen as well as antigenic preparations and immunogenic compositions comprising a PCV-2 antigen, wherein the virucidal activity has been reduced. In addition, the present invention also relates to a method of increasing the immunogenicity of an immunogenic composition comprising a PCV-2 antigen as well as immunogenic composition with an increased immunogenicity.

Field of Invention
The present invention relates to methods and compositions, for reducing the virucidal activity of compositions that would normally exhibit some degree of virucidal activity. By using the methods of the present invention, the virucidal activity of such compositions can be reduced in comparison to the virucidal activity of a composition that does not include the steps of the present invention. More specifically, the present invention relates to methods for producing antigenic Porcine Circovirus Type II (PCV-2) compositions such that they show relatively little or no virucidal activity as compared to the compositions known in the art using current detection methods, and in particular, as compared to compositions not produced by a method according the present invention. The present invention further relates to a novel immunogenic composition, preferably a PCV-2 containing composition produced according to the method provided by the present patent application, preferably characterized by reduced or no virucidal activity relative to comparable compositions described in the art. According to a further aspect, the present invention also provides immunogenic compositions comprising purified PCV-2 antigen, preferably purified PCV-2 antigen with an improved immunogenicity.
Description of the Prior Art
Porcine circovirus type 2 (PCV-2) is a small (17-22 nm in diameter), icosahedral, non-enveloped DNA virus, which contains a single-stranded circular genome. PCV-2 shares approximately 80% sequence identity with porcine circovirus type 1 (PCV-1). However, in contrast with PCV-1, which is generally non-virulent, swine infected with PCV-2 exhibit a syndrome commonly referred to as Post-weaning Multisystemic Wasting Syndrome (PMWS). PMWS is clinically characterized by wasting, paleness of the skin, unthriftiness, respiratory distress, diarrhea, icterus, and jaundice. In some affected swine, a combination of all symptoms will be apparent while other swine will only have one or two of these symptoms. During necropsy, microscopic and macroscopic lesions also appear on multiple tissues and organs, with lymphoid organs being the most common site for lesions. A strong correlation has been observed between the amount of PCV-2 nucleic acid or antigen and the severity of microscopic lymphoid lesions. Mortality rates for swine infected with PCV-2 can approach 80%. In addition to PMWS, PCV-2 has been associated with several other infections including pseudorabies, porcine reproductive and respiratory syndrome (PRRS), Glasser's disease, streptococcal meningitis, salmonellosis, postweaning colibacillosis, dietetic hepatosis, and suppurative bronchopneumonia.
Several vaccine are available to reduced the impact of PCV-2 infections in pigs. U.S. Pat. No. 6,703,023 provides a DNA based vaccine for the prophylaxis of pigs against PMWS. In WO 03/049703 production of a live chimeric vaccine is described, comprising the non-pathogenic PCV1 virus in which, however, the ORF2 protein is replaced by the ORF2 protein of the pathogenic PCV-2. WO 99/18214 and WO 99/29717 have provided several PCV-2 strains and procedures for the preparation of a killed PVC2 vaccine. Preparation of subunit vaccines have also been described in WO 99/18214 and WO 99/29717. An effective ORF2 based subunit vaccine has been reported in WO 06/072065. A further ORF-2 based subunit vaccine is described also in WO 07/28823. However, none of the vaccine described in the prior art includes a non-virucidal and/or purified PCV-2 antigen, preferably a highly purified PCV-2 ORF2 antigen.
Immunogenic compositions against PCV-2 and various immunogenic compositions against other pathogens often have a virucidal effect on other antigens. Current regulatory standards (9 CFR 113.35) permit some virucidal activity in multivalent compositions, but this virucidal activity cannot result in a loss of more than 0.7 logs/ml of a live virus or less than 0.7 logs/ml CFU of live bacteria when combined with the other components of the immunogenic composition. Compositions that have more virucidal activity than permitted cannot be combined with other antigens to create a multivalent vaccine.
Open reading frame 2 (ORF2) protein of PCV-2, having an approximate molecular weight of 30 kDa when run on SDS-PAGE gel, has been utilized in the past as an antigenic component in vaccines and immunogenic compositions for PCV-2. Typical methods of obtaining ORF2 for use in such vaccines and compositions generally consist of amplifying the PCV-2 DNA coding for ORF2, expressing the ORF2 protein within a host cell, and extracting the ORF2 protein from the host cell via cell lysis. The recovered ORF2 cell lysate is then used as the antigenic portion of an immunogenic composition or vaccine. In some cases the ORF2 containing cell lysate is separated from the cell debris.
What is needed is a method for reducing the virucidal activity of PCV-2-containing immunogenic compositions and antigens therein such that regulatory requirements can be met and efficacious multivalent compositions can be administered. What is further needed are methods for decreasing or reducing the virucidal activity and effect of PCV-2-containing compositions on Porcine Reproductive and Respiratory Syndrome Virus (PRRSV). What is still further needed are immunogenic compositions that have undergone the methods of the present invention such that their virucidal activity has been reduced to acceptable standards and can be combined with other antigens to form multivalent immunogenic compositions.

Methods of reducing virucidal activity in PCV-2 compositions and PCV-2 compositions with an improved immunogenicity


A drive arrangement effects movement of a disk conveying portion to a plurality of first positions and to a second position relative to a case and a rotatable turntable. The drive arrangement includes a driving gear, a slide member having a gear portion engaging the driving gear, and a movable slide plate engaged by the slide member, the slide plate having a stepwise cam portion which effects movement of the disk conveying portion between its positions. The disk conveying portion has two rotatable rollers which can engage an edge of a disk in the case when the disk conveying portion is in one of its first positions, and which rotate in order to extract the disk. As the disk conveying portion moves to its second position, the disk supported by the rollers moves to the turntable, and a clamp member is moved from a retracted position to a clamping position to hold the disk against the turntable, after which the rollers are disengaged from the disk.

Since CD players for car use have been developed because CDs are widely utilized, it becomes possible to enjoy music of high quality during driving. For such a CD player for car use, in order to alleviate the inattention given to the driving operation by exchanging CDs often, there is a tendency of adopting a so-called autochanger system, which is constructed such that a desired piece of music can be easily selected by setting a plurality of CDs together in a magazine and loading this magazine into a player. FIGS. 8A, 8B and 8C show the construction of a magazine 2 used in such an autochanger system. In the inner space of a box-shaped magazine 2 there are disposed a plurality of e.g. 5 spacers with a certain interval. Owing to these spacers a plurality of CDs, in this case 6 CDs can be accommodated. The spacers 8 are made of a material having a soft surface selected so as not to damage the CDs.
In the case where the player is loaded with a magazine, in which a plurality of CDs are set as described above, a CD selecting mechanism is required. This mechanism selects an arbitrary CD, takes it out from the magazine and moves it to a play position.
Heretofore such a selecting mechanism is constructed by a lead screw system utilizing a lead screw.
However the prior art CD selecting mechanism using the lead screw system has several problems as described below.
1. The precision of the selected position is low, in the case where a CD is selected from the magazine. PA1 2. The selecting operation is slow, because the lead screw is used. PA1 3. The mounting efficiency is low, because a high precision is required for positioning parts, when they are mounted in the player.


The present invention features a process and a resulting article in which copper-based multilevel interconnects are fabricated. The copper-based multilevel interconnect formed by the inventive process first includes the process step of depositing a pattern of copper lines upon or in an applicable substrate, such as silicon dioxide. The copper lines are approximately one micron thick. The lines are coated with approximately 50 to 100 nm of titanium by sputter deposition, and undergo subsequent annealing at approximately 300.degree. C. to 400.degree. C. in an argon ambient. The titanium and copper layers are annealed to provide a Cu.sub.3 Ti alloy at the copper/titanium junction. The unreacted titanium between the copper features is then stripped away by dry etching with fluorine-based etch. The remaining Cu.sub.3 Ti alloy is subsequently transformed into TiN(O) and copper by a rapid thermal annealing in an NH.sub.3 atmosphere at an approximate temperature of below 650.degree. C., and then usually at temperatures ranging from between 550.degree. C. to 650.degree. C. for approximately five minutes. The copper lines are thereby capped with a layer of TiN(O), since oxygen is incorporated into the TiN layer during the heat treatment. The TiN(O) layer is more effective as a diffusion barrier than is TiN.

The integration of a large number of components upon a single chip requires the formation of sophisticated interconnects. The interconnects should be formed with minimal signal delays and optimal packing density, in accordance with the principles enunciated in "On-Chip Wiring for VLSI: Status and Directions" by M.B. Small and D.J. Pearson, IBM J. Res. Develop., Vol. 34, No. 6 (11/6/90) pp. 858-867.
To achieve the above objectives, the preferred interconnect material is copper. Copper provides a number of advantages for wiring applications including low resistivity and a high melting point.
At present, aluminum is the material used in fabricating interconnects on most integrated circuits. This invention seeks to replace the aluminum with copper in the fabrication of advanced integrated circuits and ultra-fast logic devices.
As previously mentioned in the aforesaid U.S. patent application Ser. No. 07/790,971, the use of copper as an interconnection material presents several problems, such as (1) copper oxidizes easily at low temperatures; (2) copper has poor adhesion to substrates; (3) copper has a high diffusion in silicon dioxide and other dielectric materials used in micro-circuitry; (4) copper has a low reaction temperature with most silicides; and (5) copper requires a high temperature for patterning by reactive ion etching (RIE).
In order to overcome these disadvantages when using copper as an interconnect material, it is necessary to passify the copper surfaces and provide diffusion barriers between the copper and the adjacent layers.
It has been proposed in the aforementioned U.S. patent application Ser. No. 07/790,971, to TiN-encapsulate the copper fine line structure by annealing the copper-titanium alloy lines in an NH.sub.3 ambient. This technique is very versatile because a barrier layer can be formed simultaneously on all exposed surfaces of the copper lines.
A number of limitations to the above method have been discovered, however, particularly when forming fully-planar copper lines by filling grooves in a dielectric and removing the excess. In this case, the copper alloy must be deposited into a feature without leaving a void, so electroplating or chemical vapor deposition is required. It is difficult to deposit refractory metal-copper alloys, such as copper-titanium, with electroplating or chemical vapor deposition techniques. Additionally, any residual titanium in the copper lines increases the resistivity above that of pure copper.
The present invention discloses a self-aligning process for capping the copper lines without the need for deposition of a copper alloy (such as copper-titanium).

Self-aligned process for capping copper lines


This specification discloses a communication system across networks and the method thereof for processing remote controls of devices in a private network from a public network. By providing a server end that contains correspondence relations between client ends and mobile ends in a public network, packets in the public network are automatically transmitted to devices in a private network according to the correspondence table in the server end for remote controls. The invention increases the convenience in managing devices in a private network.

1. Field of Invention
The invention relates to a communication system and the method thereof. In particular, the invention relates to a communication system across networks and the corresponding method that can implement remote controls of devices in a private network from the client end of a public network.
2. Related Art
Due to prosperous Internet developments in recent years, networking devices requiring IP addresses also grow rapidly. The IP addresses are unique. Moreover, the widely used IP addresses are in accord with the fourth-generation protocol (IPv4), which only uses 32 bits to locate all networking devices worldwide. Therefore, the IP addresses are insufficient for current uses.
In observation of this, some vendors provide the network address translation (NAT) technique to make full use of the limited amount of IP addresses. Generally speaking, the IP addresses include public IP addresses and private IP addresses. The so-called public IP address is a legal IP address issued by an Internet service provider (ISP), i.e., a physical network address on the Internet (the public network). The private IP address is an IP address that is reserved and not issued, also called a virtual IP address. The reserved IP addresses are for an intranet (the private network). They can be arranged and issued by the network administrator according to needs. For example, the reserved IP address according to IPv4 range from 10.0.0.1 to 10.255.255.254, from 172.16.0.1 to 172.31.255.254, and from 192.168.0.1 to 192.168.255.254. A same private IP address can be used in different private networks. Therefore, this method can effectively solve the problem of insufficient IP addresses. However, since different private networks may have the same private network addresses, packets cannot be freely transferred between private and public networks in order to avoid incorrect addressing. To transmit, packets have to rely on an intermediate end between the private and public networks and supporting IP address translations, such as an IP router.
However, the above-mentioned IP address translation requires a first device in the private network to sends a connection request to a second device in the public network, so that the correspondence relation between IP address of the first device and the second device is recorded in a correspondence table at the intermediate end during the connection request. The correspondence table is then used for packet transfers. Therefore, if the first device does not send a connection request to the second device, it is impossible for the second device in the public network to perform a remote control on the first device in the private network.
In summary, the prior long has the problem that the second device in the public network cannot actively perform remote controls on the first device in the private network. It is therefore highly desirable to provide a solution.

Communication system across networks and method thereof


A system and method for simplifying Session Initiation Protocol (“SIP”) Back To Back User Agent (“B2BUA”) development by associating different call legs with each other across multiple SIP entities. Call legs may be associated with one another through a common or shared identification.

The present disclosure relates to call identification by a Session Initiation Protocol ("SIP") Back To Back User Agent ("B2BUA").
Session Initiation Protocol ("SIP") is a protocol or standard for handling an interactive user session. The session may involve any multimedia element. Voice over IP ("VoIP") calls may use SIP. SIP is used as a signaling protocol in many different VoIP offerings, including for example Microsoft Live Communications Server and the 3GPP IP Multimedia Subsystem ("IMS") architecture. Generally, SIP is a protocol for establishing and using multimedia communications.
A Back To Back User Agent ("B2BUA") may be a logical entity that acts as an intermediary in a SIP call. A Signaling gateway that is part of a Session Border Control ("SBC") may be an example of a B2BUA. A B2BUA may also be an interface in an IP Multimedia Subsystem ("IMS") network between the IMS and an external network. The B2BUA may be a proxy for both ends of a SIP call and act as a server on one end and a client on the other end that handles all SIP signaling. In one example, the B2BUA may act as both a client (UAC) and a server (UAS) to both ends of a call. When one client sends a request, acting as a UAC, to the B2BUA, which acts as a UAS to receive the request. The B2BUA may then act as a UAC to send the potentially modified request to another endpoint, which uses UAS functionality to receive the request. If the endpoint then responds, the response is sent using UAC from the endpoint to UAS on the B2BUA. After B2BUA processing, the response is transmitted from the B2BUA via UAC functionality before being received back at the starting endpoint via UAS functionality. In other words, a request may be both sent via UAC functionality and received via UAS functionality.
Specifically, in the SIP specification for the RFC 3261 standard, B2BUA is defined as:                . . . a logical entity that receives a request and processes it as a user agent server ('UAS'). In order to determine how the request should be answered, it acts as a user agent client ('UAC') and generates requests. Unlike a proxy server, it maintains dialog state and must participate in all requests sent on the dialogs it has established. Since it is a concatenation of a UAC and UAS, no explicit definitions are needed for its behavior.
The B2BUA may allow for additional tracking of calls as well as allow for new features that would otherwise be unavailable in a traditional end to end call. The B2BUA may receive, respond to, and generate requests. In other words, the SIP signaling, from call origination to call termination can be controlled by the B2BUA. The B2BUA may include call management functions, network interworking, SIP-based VoIP interworking, managing/monitoring entire call state, cloaking endpoint location, centralized call management, and the hiding of network internals. It may maintain records of all requests or connections that are established by tracking each call. Consequently, value-added features may be offered in the call as a result of the B2BUA.
The RFC 3261 specification does not contain any recommendations for B2BUAs on how to associate incoming/outgoing/multiple call legs belonging to the same call/conference. Current B2BUA implementations normally generate a random and unique Call-ID header for the outbound call leg. RFC3261 describes a Call-ID as a header field acting as a unique identifier to group together a series of messages. It may be the same for all requests and responses sent by either UA in a dialog. In addition, the Call-ID may be one of three elements, in addition to the 'To' tag and the 'From' tag, that define a SIP dialog. The SIP dialog may define a unique peer-to-peer SIP relationship between two entities.
For example, for a message from user A to user B with Call-ID 1111 and another message also from user A to user B but with a Call-ID of 2222, there are two different dialogs or communications sessions. For instance, Call-ID 1111 could be for a VoIP session and Call-ID 2222 could be for an Instant Messaging session. The use of a B2BUA between the endpoints may disrupt the normal peer-to-peer communications between SIP endpoints. The technique used by a SIP endpoint to determine which SIP sessions are a part of a given conference is to rely on the Call-ID. All sessions with the same Call-ID at a given endpoint may be considered to be part of a single conference. If the B2BUA generates random Call-IDs on call legs that it extends, the endpoint will not be able to successfully recognize the conference because of the differing Call-IDs. The ability to maintain the same Call-ID may be required by endpoints for some SIP features, such as MICROSOFT'S MULTI-PARTY IM®. This is one scenario in which a constant Call-ID is required, however, there may be additional programs or circumstances that also require a constant Call-ID. In addition, there may be situations where call legs are terminated and later re-established. In this situation, the generation of a new Call-ID by the B2BUA makes it difficult for the endpoint to recognize that the "new" call leg is simply the reestablishment of the previous call leg. This may be important for historical call tracking.
FIG. 1 illustrates a related art conference setup. FIG. 1 shows a conference 100 in which three users 102, 104, 106 are connected according to the related art. The conference may be an instant messaging ("IM") conference, Voice over IP ("VoIP") call, or any other connection. In this example, there is no B2BUA in the network, so the calls are routed directly. Additionally, there may be a SIP proxy, but it is omitted from FIG. 1. Each User 102, 104, 106 is labeled independently. User A is 102, User B is 104, and User C is 106.
As shown in FIG. 1, User A originates a call with User B by sending an invitation 108 to join in a call. The call may be an IM session. As part of the invitation 108, User A creates a SIP Call-ID, such as 1234. The SIP Call-ID identifies the call. Subsequent to the invitation 108, User B requests 110 that User A invite User C into the call. User A sends invitation 112 to User C using the same Call-ID as from the invitation 108. The invitation 112 may also pass a list of conference participants notifying User C that User A and User B are in the call. User C may then send out invitations to the other parties in the conference. For example, User C sends out invitation 114 to User B using the same Call-ID to identify the call. Accordingly, conference 100 has three endpoints and each have the same Call-ID. From the perspective of an individual endpoint, all sessions that have the same Call-ID are considered to be part of the same conference.
FIG. 1 illustrates a system 100 that has a conference call between endpoints without the presence of a B2BUA. FIG. 2 illustrates a related art system using a B2BUA. Specifically, conference 200 illustrates a conference call is established with a B2BUA 208 in the network in which three users 202, 204, 206 are connected. Additionally, there may be a SIP proxy, but it is omitted from FIG. 2. Each User 202, 204, 206 is labeled independently. User A is 202, User B is 204, and User C is 206.
As shown in FIG. 2, User A originates a call by sending an invitation 210 to User B. User A creates a SIP Call-ID, such as 1234. The invitation 210 goes through the B2BUA 208. The B2BUA generates a new call leg 212 to User B. The generation of new call leg 212 results in the generation of a new Call-ID, such as 2000. User B subsequently may ask User A to also include User C in the call in 214. User A then sends an invitation 216 to User C using the same Call-ID used in the original invitation 210, which is Call-ID 1234, and passes a list of conference participants to User C. The invitation 216 goes through the B2BUA. The B2BUA generates a new call leg 218 to User C. The call leg 218 is generated with a new Call-ID, such as 3000. User C sends out invitation 220 to User B, who is the other user in the conference. The invitation 220 is sent using the same Call-ID that User C received, which is 3000. The invitation 220 goes through the B2BUA. The B2BUA may then generate a new call leg 222 to User C. Call leg 222 results in the generation of another new Call-ID, such as 4000.
The conference 200 that is attempted after call leg 222 includes multiple Call-IDs for the different call legs. At this point, User B is unable to correlate the sessions. User B's session with User A has an ID of 2000 and User B's session with User C has an ID of 4000. As a result, the conference may fail. Accordingly, the use of a B2BUA in the conference 100 results in a conference 200, which fails because of the inability of some endpoints to correlate the sessions between end users.

System and method to identify and associate call legs in session initiation protocol back to back user agents


Embodiments of the invention provides, among other things, methods for identifying agents that inhibit oncogenic transcription factors, induce apoptosis, inhibit the growth of transformed cells and cancer cells, and potentiate the effects of other agents that induce apoptosis and that inhibit the growth of transformed cells and cancer cells. Embodiments of the invention further provide compositions useful for the same comprising an agent the inhibits one or more oncogenic transcription factors and an agent that induces apoptosis, particular compositions wherein the apoptotic effect of the combination is greater than either agent by itself. Embodiments of the invention further provide for the use of such agents and compositions to treat cancer. In illustrative embodiments the agents that inhibit transcription factor activity are thiazole antibiotics, such as Siomycin and thiostrepton, and the apoptosis inducing agent is a member of the TNF ligand superfamily, such as TNF-alpha. In illustrative embodiments the cancers are those in which both the FoxM1 and the NF-kB oncogenic pathways are activated.

Oncogenic transcription factors are important mediators of process involved in cell growth, differentiation, and de-differentiation, and they play important roles in oncogenesis, cancer progression, and metastasis.
For instance, the forkhead box (Fox) family of transcription factors plays important roles in regulating cellular proliferation, differentiation, longevity, and cellular transformation. Wang et al., Proc. Natl. Acad. Sci. USA 98:11468-11473 (2001). The mammalian transcription factor Forkhead Box M1 (FoxM1; previously known as HFH-11B, Trident, WIN, or MPP2) is induced during the G1 phase of the cell cycle, and its expression continues through the S phase and mitosis (1). FoxM1 is especially important for the execution of the mitotic program as seen by the failure of FoxM1-depleted cells to progress beyond the prophase stage of mitosis (2). This is consistent with the demonstration that FoxM1 transcriptionally upregulates a number of target genes including Cyclin B, Survivin, Aurora B kinase, Cdc25b phosphatase, and Plk1, all of which are implicated in mitosis (2, 3). Also, FoxM1 transcriptionally induces Skp2 and Cks1 (specificity subunits of Skp1-Cullin1-F-box ubiquitin ligase complex) leading to the degradation of cyclin-dependent kinase inhibitors p21WAF1 and p27KIP1, thereby resulting in cell cycle progression (2). In line with its pro-proliferative nature, while FoxM1 is expressed in all dividing mammalian cells and tumor-derived cells, its expression is turned off in terminally differentiated cells (4-7).
FoxM1 is overexpressed significantly in primary breast tumors (8), basal cell carcinomas (9), hepatocellular carcinomas (10, 11), intrahepatic cholangiocarcinomas (12), non-small cell lung cancers (13), anaplastic astrocytomas, and glioblastomas (14). Also, increased levels of FoxM1 has been seen to accelerate prostate cancer development and progression in mouse models (15). Furthermore, a large-scale analysis of microarray results revealed that FoxM1 is one of the most common genes overexpressed in a majority of solid tumors (16). Together, these studies indicate that FoxM1 could be an attractive target for anti-cancer therapy. This notion is supported by a recent finding that depletion of FoxM1 by RNA interference (RNAi) in breast cancer cells leads to mitotic catastrophe (8). In a similar manner, knock-down of FoxM1 by small interfering RNAs (siRNAs) in several prostate and lung cancer cell lines was shown to lead to a significant reduction in cell proliferation and anchorage-independent cell growth on soft agar (13, 15). Consistent with these observations, inhibition of FoxM1 transcriptional activity by a peptide containing amino acids 24-46 of p19ARF also reduced anchorage independent cell growth (17).
The central role of oncogenic transcription factors, such as FoxM1, in regulating cell growth, proliferation, and differentiation, and in pathologies associated with changes in their functioning, such as cancers, makes them attractive targets for drug development. Accordingly, there has been a great deal of research and development work not only on characterizing these factors and their roles in cellular and disease processes, but also on therapeutic agents that modulate their activity. Although these efforts have resulted in some success, the agents that have been developed thus far are far from ideal. There is a need therefore for improved methods of identifying agents that modulate the activity of oncogenic transcription factors, and for the agents themselves, as well as for formulations comprising the agents and for methods of using the agents and composition to treat diseases, such as malignancies and cancers.

Identification and use of agents that modulate oncogenic transcription agent activity

The Board of Trustees of the University of Illinois


An embodiment of a method for call management, performed by a processing unit of a mobile device, is introduced. A telecommunications network is notified to block MT (mobile-terminated) calls through a base station after the mobile device has successfully associated with a WLAN (wireless local area network) AP (access point) deployed in a region in which noises should be avoided or limited, so as to avoid sounding a ringtone in response to a receipt of a paging reques

1. Technical Field
The present invention relates to call management, and in particular, relates to methods for barring MT calls and apparatuses using the same.
2. Description of the Related Art
Users can experience embarrassment when bringing a mobile phone in a quiet region, such as a lecture hall, a cinema, a library, a recording studio, an assembly hall, or others, but the mobile phone sounds a ringtone for an incoming call. There are two ways to prevent the bothersome ringtone. The user may power-down the mobile phone or manually switch the mobile phone to silent mode when seeing a posted notice, watching a reminder video, or hearing a broadcast at a particular place. Although this can avoid the bothersome sound, many users usually forget to turn their mobile phones back on and restore the ring settings, resulting in their potentially missing incoming calls. A mobile phone blocker may be employed at a particular location to interfere with or block radio frequency (RF) signals to cause nearby mobile phones to lose the ability to receive any messages broadcast from a base station. However, the mobile phone blocker bars not only incoming call requests but also other communications signals, causing the mobile phone to be unable to make outgoing calls, receive and send short messages and e-mails, and surf the Internet. In addition, the mobile phone will attempt to increase its power level to search for available cells when camping on no cell, resulting in the unnecessary consumption of battery power and a reduction in the life of the battery.
Therefore, there is a need for technologies that will allow a mobile phone to block only MT call signals but do not affect other communications when entering a particular region, and that cancels the blocking after the mobile phone in question has left the region.

Methods for barring MT calls and apparatuses using the same


A modular unmanned aerial vehicle (UAV) having a fuselage, a nose cone, a left wing piece, a right wing piece, and a tail section. The tail section and nose cone each join to the fuselage through mating bulkhead structures that provide quick connection capability while being readily separated so as to enable the UAV to break apart at these connection points and thereby absorb or dissipate impact upon landing. The UAV is capable of rapid assembly in the field for two-man launch and data retrieval, as well as quick disassembly into these five component parts for transport and storage in a highly compact transport case that can be carried as a backpack.

1. Field of the Invention
The present invention relates generally to unmanned aircraft and, more particularly to a hand-launchable unmanned aerial vehicle (UAV) carrying sensor instrumentation for terrain surveillance, in which the components of the UAV are easily assembled in the field, can absorb landing shocks, and can be disassembled so as to fit in a small size package.
2. Description of the Related Art
There is a need for a small size unmanned aerial vehicle (UAV) which is able to collect data from a sensor such as a television camera carried on board the UAV and transmit the collected data to be received by a ground receiver, as for example at the point of launch.
Such a UAV must be capable of being disassembled, transported in a small size container to the point of launch, then quickly reassembled and launched, for data retrieval. With known UAV designs, the assembly process is often slowed due to the nature of the component connection elements which are often difficult to align and which can appear to be connected properly when in fact, the components are slightly out of alignment.
Once in flight, conventional UAV wing designs in which the servos controlling the elevons are mounted on the fuselage often cause the UAV to oscillate, resulting in instability that can negatively impact the data gathering mission.
Further difficulties often arise when the UAV returns upon completion of a surveillance mission, in that the landing process frequently results in considerable damage to the airframe of the UAV. This damage typically results when one of the wings is caught or collides with a ground-based object, twisting the airframe and tearing the wings and/or fuselage. Damage to the UAV may also occur as a result of the abruptness of the landing which can be caused when the launching clip tunnels into a soft ground surface, acting like an anchor and causing the UAV to flip or tumble rather than skidding on its belly.
Therefore, a need exists for an UAV that is constructed to absorb or dissipate the impact of landing without sustaining damage to a degree that would prevent nearly immediate redeployment, i.e., reuse while still in the field. The UAV must also be readily assembled and disassembled, with positively connecting components that provide fast and foolproof connection in a mission environment using a minimum of tools and requiring minimal operator training. Finally, the UAV must be constructed to have a low "ground adhesion" characteristic to further reduce shock and to maintain a steady airframe skid orientation upon landing.

Autonomous, back-packable computer-controlled breakaway unmanned aerial vehicle (UAV)


In an exemplary embodiment, a motor assembly includes a shaft and a compound fan assembly that provides axial and centrifugal air flow. The fan assembly includes a body including an outer surface, a cavity defined by the body outer surface, a plurality of first blades extending radially outwardly from the body outer surface, and a plurality of second blades disposed within the cavity. The shaft is concentric with the body and the second blades are rotatably coupled to the shaft.

This invention relates generally to fans, and more particularly, to electric motor assemblies that include fans.
Fans are incorporated into different types of machines and systems including heating, ventilating, and air-conditioning (HVAC) systems. HVAC systems typically utilize supply and exhaust or return air fans. In addition, high-efficiency centrifugal fans have sometimes been used to supply air through duct systems and to cool motors. Such fans are chosen based on aerodynamic, economic, and functional suitability considerations.
Many HVAC systems utilize relatively large axial flow fans in condenser units to draw air across a plurality of condenser coils. These systems also typically utilize auxiliary centrifugal fans to draw cooling air through the axial fan motor. Such dual fan systems use a long shaft to mount the two separate fans. In addition, such systems, wherein an end user or wholesaler mounts the fans to a shaft, are subject to vibration and noise problems and require additional assembly.
In an exemplary embodiment, a motor assembly includes a compound fan assembly that generates axial air flow and centrifugal air flow. The fan assembly includes a body including an outer surface, a cavity defined by the body outer surface, a plurality of first blades disposed within the cavity, and a plurality of second blades that extend radially outwardly from the body outer surface. The fan assembly further includes a shaft concentric with the body, the second blades and a least a portion of the first blades configured to be rotatably coupled to the shaft. The first blades and the second blades are configured such that the first blades discharge air in a first direction and the second blades discharge air in a second direction.
In practice, the first blades draw air across a condensing unit, and the second blades draw air up through a motor to cool the motor. The motor shaft, the first blades, and the second blades are combined into a single part to improve efficiency. This single part is either manufactured through a molding process or assembled from components manufactured from stamped metal.

Combined axial flow and centrifugal fan in an electrical motor


A compressed hay bale cutting and stacking system includes a compressed bale cutter and a stacker arranged to stack half-cut or quarter-cut bales in multi-tier stacks while maintaining slices of the bales in substantial alignment. The bale cutter is oriented to discharge the half-cut or quarter-cut bales as a unit at a predetermined elevation. The stacker has a table assembly and a pushoff assembly positioned to receive each bale as a unit from the bale cutter and automatically form a stack of at least 2 bale by 2 bale tiers. The table assembly has an elongate first platform movable vertically on the stacker frame between a raised position aligned with the bale cutter discharge to form a first row of bales and a lowered position for receiving a second row of bales, to accumulate a tier of stacked bales while maintaining the bales substantially aligned along their vertical sides. The pushoff assembly is mounted on the frame with a vertical pushoff plate adjacent the table assembly and is extendable across the platform when in the lowered position to sweep each tier of stacked bales off the platform to add it to a stack.

This invention relates generally to apparatus for recompacting, slicing and stacking hay bales into high density compact units.
In the packaging of baled hay for international shipment, it is become commonplace to recompact the hay bales for efficient and economical handling and shipping. As further described, for example, in U.S. Pat. No. 5,001,974, conventional hay bales weighing about 50 kg. (110 pounds) are compressed to about half their field length.
In order to make the recompacted bales easier to handle manually, the recompacted bales can be passed through a cutting means to sever it into two uniform size and weight bales suitable for handling, shipping, and manual handling at the destination. The above-referenced patent describes the use of a double-edged knife blade mounted for vertical reciprocal movement in vertical guides, to cut each recompacted bale along a vertical plane. As an alternative to this method, I have previously built and used what I refer to as a box knife. The box knife has a chamber that is mounted at about a 30.degree. angle from horizontal; a fixed knife blade mounted across the chamber adds the same 30.degree. angle and positioned at about 20.degree. angle from perpendicular to the length of the chamber. A hydraulic ram mounted at one end of the chamber presses each recompacted bale, which is dropped into the chamber in such a way that its straps are oriented parallel to the knife, i.e., at about 30.degree. from horizontal, and pressed through the box knife to slice the bales in half.
An alternative approach to hay recompression is described in my U.S. Pat. No. 5,392,591, which describes enclosing the recompacted bale in an elastomeric net, rather than securing it with straps, and cutting the bale in half at various positions in the recompaction process.
To facilitate shipping, the recompacted bales are assembled into stacks of various sizes, consisting of K-N-M rows, columns and layers of bales. Conventionally, the bales have been stacked manually and thereafter handled by a squeeze truck and then wrapped or strapped into a unit so that the stack can be easily handled either by a squeeze truck or lift truck during loading into and unloading from a shipping container. Manual stacking is very hard work and time consuming but attempts to automate the stacking process have also encountered difficulty. One difficulty is that the half-cut bales do not stack easily, particularly if they have been cut on a vertical plane.
Simpson Equipment Company has previously marketed a box knife-type bale cutter consisting of an elongated chamber with a plunger in one end and a knife blade fixed across the opposite end in the middle of the chamber, the chamber having a hopper for receiving compressed hale bales between the plunger and the fixed knife. This type of bale cutting device was oriented with its sides at about a 45.degree. angle to the horizontal and vertical planes and the knife fixed at about 45.degree. from vertical. The half-cut compressed bales are then conventionally hand stacked and the stacks are preferably unitized for easy handling by a lift truck or squeeze truck, as is known in the art, and then loaded into a shipping container.
Once the shipping container reaches its destination, the stacks of half-cut compressed bales are unloaded and trucked to a feedlot or dairy farm where the half-cut hale bales are removed from the stack and fed to livestock. Handling of the half-cut bales is often done by hand, which is very difficult work even for half-cut bales.
Accordingly, a need remains for ways to improve the efficiency of processing compressed hale bales, cutting and stacking them and handling them when they reach the end user.

Recompacted hay bale cutting and stacking system


A sealant melter incorporates a sealant block feed assembly that reduces the labor required to feed sealant blocks to the sealant tank of the melter and that reduces or even eliminates the risk that hot liquid sealant will splash out of the sealant tank when sealant blocks are fed into it. The sealant block feed assembly preferably includes a top-fed splash box and a conveyor assembly for feeding sealant blocks to the splash box from a towing/storage vehicle or the like. The splash box incorporates internal guards in the form of counterbalanced flaps that prevent hot liquid sealant from splashing out of the splash box when the sealant blocks are fed into it from above. The conveyor assembly includes a conveyor that is selectively controllable, either from the towing/storage vehicle or from curbside, to receive sealant blocks and to selectively feed the received sealant blocks to the splash box. The height and/or the length of the conveyor can be varied to meet the needs of a particular towing/storage vehicle, and the entire sealant block feed assembly is configured for detachably mounting on the sealant melter frame so as to be easily retrofittable on a previously-assembled sealant melter.

1. Field of the Invention
The invention relates to sealant melters and, more particularly, relates to a sealant melter having a sealant block feed assembly for the controlled delivery of sealant blocks to a heated sealant tank of the sealant melter without splashing and to a retrofittable sealant block feed assembly usable with a sealant melter.
2. Discussion of the Related Art
Sealant melters are well-known for use in conjunction with applicators that apply a viscous hot liquid sealant to joints or cracks in concrete, asphalt, or the like. The typical sealant melter includes a mobile frame (typically a trailer) on which is mounted a melter and an applicator. The applicator typically takes the form of a wand or nozzle. The melter typically takes the form of a sealant tank and a liquid fuel-fired heater mounted on the frame adjacent the sealant tank and operable to supply heat to the sealant tank. The heated sealant tank melts blocks of sealant and stores the hot liquid sealant for subsequent dispensation to the applicator.
Feeding sealant blocks to the traditional sealant melter is a labor-intensive task that places operators at risk of being splattered by sealant splashing from the sealant tank. Sealant blocks typically are delivered to a worksite by a towing/storage vehicle (typically a dump truck, flatbed truck, or the like) that hauls the sealant blocks and that also tows the trailer. Solid sealant blocks, typically weighing about 30 lbs, are delivered one at a time from a first operator stationed on the towing/storage vehicle to a second operator stationed on the ground. The second operator then delivers the sealant blocks one at a time through an upper inlet in the sealant tank. This inlet typically is located at or near the level of the second operator's head. The second operator therefore must expend substantial effort in delivering sealant blocks to the sealant tank. If the sealant tank is nearly full, hot sealant (on the order of 500.degree. F.) may splash out of the sealant tank upon the ingress of the sealant blocks and splatter on the surrounding area and even on the second operator.
Hence, there is a need for a sealant block feed assembly that is usable with a sealant melter and that facilitates the supply of sealant blocks to the sealant tank.
One prior attempted solution to this problem involved the use of an unpowered gravity-feed roller conveyor that led from the towing/storage vehicle to a receptacle on the sealant tank. The receptacle took the form of a box having an inlet in one of its vertical sides. The roller conveyor sloped downwardly from the towing/storage vehicle to the side inlet of the receptacle so that sealant blocks placed on its upper end slid by gravity into the side inlet of the receptacle.
The sealant block feed assembly using an unpowered conveyor and a side-fed receptacle proved imperfect. The receptacle may have helped reduce splashing, but its front or side inlet terminated so close to the inlet opening of the sealant tank that it could not assuredly prevent liquid sealant from splashing out of the sealant tank upon sealant block ingress. Moreover, there was no practical way to arrest sealant block movement along the conveyor and hence no way to prevent sealant blocks from sliding into the receptacle once they were placed on the conveyor. Sealant blocks therefore could not be loaded in batches by a single operator and then subsequently fed one at a time into the sealant tank from curbside but instead needed to be fed to the receptacle one at a time by an operator stationed on the vehicle. In addition, the sealant block feed assembly was difficult to retrofit onto previously-assembled sealant melters.

Sealant melter with retrofittable sealant block feed assembly


A microwave cavity including a pair of opposing clamshell halves, such halves comprised of a metal selected from the group consisting of silver, copper, or a silver-based alloy, wherein the cavity is further characterized as exhibiting a dominant TE.sub.011 mode is provided together with an embodiment wherein the interior concave surfaces of the clamshell halves are coated with a superconductive material. In the case of copper clamshell halves, the microwave cavity has a Q-value of about 1.2.times.10.sup.5 as measured at a temperature of 10K and a frequency of 10 GHz.

Conventional right-circular cylindrical resonant cavities have several electromagnetic modes. One mode of typical interest is the TE.sub.011 mode. This mode has the electric field flowing circumferentially, which implies that no electric currents cross a joint if, for example, the end walls are removed. This type of electric flow is important as it allows the replacement of the end walls with other materials and measures surface resistance without concern about accounting for losses due to electric currents crossing a joint. Unfortunately, the TE.sub.011 mode is degenerate with a TM.sub.111 mode, which does in fact have currents that flow across joints. For right circular cylinders these two modes can be separated with a mode separator, i.e., a notch in the bottom of the cavity. Such a notch perturbs the two modes such that the TE.sub.011 mode is separated in frequency from the TM.sub.111 mode. This result is easily seen on the transmission curve of the cavity. While such a system has the desired concomitant circumferential electric field, the design, in particular the dimensions, of a right-circular cylindrical cavity is generally unsuitable for coating with superconductive materials, especially high temperature superconductive materials. It has become highly desirable to coat microwave cavities with superconductive materials, especially high temperature superconductive materials, so as to increase the quality factor, i.e., the Q-value, of the cavity as well as the performance of the cavity.
Accordingly, it is an object of this invention to provide a microwave cavity having a geometry adapted for subsequent coating by a superconductive material, preferably a high temperature superconductive material.
Another object of this invention is to provide a microwave cavity having a geometry design wherein the TE.sub.011 and TM.sub.111 modes are separated without the need for a mode separator.
It is a still further object of this invention to provide a microwave cavity having its interior surfaces coated with a superconductive material, preferably a high temperature superconductive material.

Clamshell microwave cavities having a superconductive coating

The Regents of the University of California


A guide for a machine tool or tool drive (7) means for moving a surfacing tool over the substantial surface of a work piece (1), said guide comprising a guide means adapted for positioning over said work piece, said guide means including two horizontal spaced apart guide rails (2) and a gantry (3) adapted for linear travel in an X-axis along said guide rails wherein said gantry includes a gantry rail (4) adapted to bridge said spaced apart guide rails, a pair of gantry arms (5) fitted to either end of said gantry rail each gantry arm having a gantry foot for co-operating with said guide rail wherein said tool drive (7) is fitted to said gantry by a gantry mount adapted for lateral movement along the length of said gantry Y-axis, said mount including a vertical Z-axis height adjustment face plate (9) for mounting said tool drive wherein the fitting of said gantry rail to said guide rails is adjustable about said X-axis and the fitting of said tool drive to said gantry mount is adjustable about said Y-axis such that the cutting face of a tool fitted to said drive can be adjusted to correspond to the surface on planar face of said work piece without the need to clamp said work piece to said guide.

The machining of large pieces of wood or wood related material, particularly of a type which occur when large slabs or flitches of timber require machining, pose particular problems for the machinist if a refined or high level of machining and finish are required of the finished product of the tool. Traditionally timber logs are prepared in a timber mill by way of large band sawing operations or small scale operations including preliminary machining which can be accomplished by chainsaw mills. Such mills are readily available and provide a tracking or guide system for operating a chainsaw such as a horizontally positioned log or piece of work can be sawn horizontally into a series of slabs by the controlled movement and guiding of a large chainsaw with the use of an apparatus known as a chainsaw mill.
While such machining accomplishes a task of reducing a wooden log to a series of slabs or flitches, the very nature of chainsaw mill operations and even industrial band saw mills results in a very rough and preliminary machining finish which leaves the task for the furniture builder or cabinet maker to dress the slab product into a more suitable form for production of furniture and the like. Such machining is traditionally accomplished by way of joiners and thicknesses, which plane the surface of a wooden slab to the required dimensions. Similarly drum sanding devices can accomplish a similar result. However, such devices when put to the task of machining large dimensions of slabs of timber result in very heavy duty and expensive apparatus which is not readily available outside of the commercial and industrial sphere. One object of the invention is to provide an improved guide for a machine tool or a tool drive adapted for surface dressing and finishing large slabs of timber or similar products where the guide can be readily adjusted and fine tuned to control the action of a cutting tool and/or sanding tool.
Whilst prior art machines are available for mounting cutting and sanding tools in the manner of the machine described above; when large cutting tools are used or sanding disks having a substantial surface or working area in contact with the work piece, prior art tools are often found to be deficient particularly in their inability to fine tune and very precisely align the working face of the tool in a plane corresponding precisely with the plane of the work piece in question.
One object of the invention is to provide an improved machine tool guide.


A device and method for plugging a tube that includes setting a tapered plug in a tube with a compression ring that circumscribes the plug. The ring radially expands when axially compressed and wedges the plug in the tube. An anchoring assembly fits over the tapered end of the plug and is coupled to the plug while being pushed against the compressed ring. When coupled to the plug, the anchoring assembly maintains the ring in a compressed state. The anchoring assembly can be made up of legs that fasten to the tapered end of the plug and have shoulders attached on a free end that are positioned against a lateral side of the compressed ring.

1. Field of the Invention
The present invention relates to an apparatus for use with a fluids handing device. More specifically, the invention relates to an apparatus for plugging a fluid passage in a tube sheet.
2. Description of the Related Art
Heat exchangers for transferring heat between two different fluids typically employ multiple tubes having an inlet and an outlet both held by a tube sheet. Bores are formed through the tube sheet that register with the end of the tubes. The tubes may experience a leak along their body or where they join with the tube sheet. Corrective action may involve plugging the leaking tube at one or both ends rather than mending the leak itself. A prior art example of a plug assembly 10 is shown in a perspective and partial sectional view in FIG. 1.
In the prior art example of FIG. 1, the plug assembly 10 is set within a tube 12 to provide a pressure and flow barrier through the tube 12. The plug assembly 10 is made up of a tapered plug 14 having a blunt end and a narrow end. The body of the plug 14 narrows linearly from the blunt and narrow ends. An annular compression ring 16 surrounds a portion of the plug 14 and has an undulating outer surface along the length of the ring 16. The undulations fill a radial space between the outer surface of the plug 14 and inner surface of the tube 12. Typically, the plug 14 and an uncompressed compression ring 16 (not shown) are inserted into the tube 12, with the blunt end being inserted first. When initially inserted into the tube 12, the outer diameters of the undulations on the compression ring 16 are exceeded by the inner diameter of the tube 12, so that the plug 14 and uncompressed compression ring 16 may be inserted into the tube 12 largely unimpeded. An installation tool, not shown, having an outer sleeve is inserted into the tube 12. A force F pulls the plug 14 in the direction shown in FIG. 1 while the outer sleeve is held in place against a lateral side of the compression ring 16. The force F urges the plug 14 axially through the ring 16 and the outer sleeve retains the compression ring 16 in place. Continued pulling repositions the plug 14 within the ring 16 so that a larger diameter portion of the plug 14 is circumscribed by the compression ring 16. Continued pulling positions the ring 16 onto larger diameter portions of the plug 14, thereby increasing the force required to slide the ring 16 over the plug 14. Eventually, the resistive sliding force of the increasing diameter of the plug 14 overcomes the yield strength of the compression ring 16 and the ring 16 compresses by the combination of the pulling force F and presence of the sleeve. When axial compressed, portions of the ring 16 radially expand into spaces between the plug 14 and tube 12. The sleeve is then removed from the tube 12 along with the tool that applied the pulling force F. While the undulating peaks on the outer surface of the compression ring 16 can become deformed and provide a tight fit, over time the compression ring 16 may slide along the plug 14 towards the tapered end and introduce a risk of removing the pressure barrier provided by the plug assembly 10.


A method for link fault detection and recovery based on Address Resolution Protocol (ARP) interaction, including: configuring an IP address and a mask code, a strategy routing or static routing module and an ARP module for network devices of a home terminal and an opposite terminal; the strategy routing or static routing module regularly inquiring whether an ARP entry to which a next hop corresponds exists, if the ARP entry exists, a link being available, otherwise, notifying the ARP module to perform keepalive on the next hop; and the ARP module performing a process of keepalive on the next hop, and after performing keepalive on the next hop, notifying the strategy routing or static routing module to judge whether the link is available. Further, a device for link fault detection and recovery based on ARP interaction.

Static routing refers to routing information configured manually by a network manager. When a topology structure of a network or a link state has a change, the network manager needs to manually modify the related static routing information in a routing table. The static routing information is private by default, and will not be transferred to other routers. Of course, the network manager can also make the static routing information become shared by setting a router.
Strategy routing is a data packet routing forward mechanism which is more flexible than routing based on a target network. Using the strategy routing, the router will determine how to process a data packet needed to be routed through a routing map, wherein the routing map determines a next-hop forwarding router of one data packet. With the strategy routing, the routing map used by the strategy routing must be specified, and the routing map needs to be created. One routing map is comprised of lots of strategies, and each strategy defines one or more matching rules and corresponding operations. After the strategy routing is applied on one interface, all packets received by this interface are detected, and a data packet which does not comply with any strategy in the routing map will be processed in accordance with a usual routing forward, and a data packets which complies with a certain strategy in the routing map will be processed in accordance with the operation defined in the strategy.
Equal-Cost Multipath Routing (ECMP) exists in a network environment where a plurality of different links arrive at the same destination address. If a traditional routing technology is used, the data packets transmitted to the destination address can only use one link therein, and other links are in a standby state or a failure state, and it is needed a certain time for switching with each other in a dynamic routing environment; however, an equal-cost or equal-value multipath routing protocol can use a plurality of links at the same time in the above-mentioned network environment, which not only increases transmission bandwidth, but also can back up the data transmission of the failure link without delay and packet loss. The greatest characteristic of the ECMP is to implement the purpose of multipath load balancing and link backup with equal-cost or equal-value, and both the strategy routing and the static routing substantially support the ECMP function.
The ARP is to transform an Internet address of a machine into a physical address. The IP data packet passes through physical networks one after another when being propagation in the Internet, and when arriving at the destination network, the IP data packet needs to be transmitted through the last physical network to a destination host. When passing through the physical network, the data packet needs the physical address of the machine, while the IP address of the machine is used for the transmission of the data packet, so one mechanism is needed to transform the IP address of the machine into the physical address.
Both the static routing and the strategy routing are based on configuration, and cannot transmit messages actively, and after an outcoming interface of the routing (a physical port of a home terminal to which a link corresponds) is from down to up, the link can be used theoretically. However, in fact, the outcoming interface of the routing being up does not represent that the link is available.
For example, when the home terminal and the opposite terminal connect using a layer 1 or layer 2 device, the method of detecting whether the next hop is available using a state of the outcoming interface of the routing is not able to detect the connectivity of the next hop; when the outcoming interface of the routing is up but the link is abnormal, the ECMP uses this link, which results in that all traffic which selects this link is discarded; and, in addition, if the outcoming interface of the routing is up, the link is normal, but forwarding information (e.g., ARP) of the opposite terminal cannot be learned immediately, then it will be also resulted in discarding the traffic which is transmitted in a certain time before learning the forwarding information.
A protocol of being able to detect the link state based on IP messages is needed to detect the state of the physical link and be able to be cooperated with the static routing and the strategy routing. A Chinese patent with an application No. CN200710187500.0 (a method for fault detection and link recovery based on a bidirectional forwarding link) provides a method for detecting the physical link based on Bidirectional Forwarding Detection (BFD). The BFD supports fast detecting the link state with a message transmission interval being a minimal value of 3.3 ms, so the BFD has natural advantages in terms of fast fault detection. In the respect of fault recovery, the BFD transmits a unicast IP message to trigger ARP learning, which ensures that the traffic can be normally forwarded on the link when the BFD detects that the link fault is recovered.
However, there are some disadvantages for using the BFD to detect the link state, that is: the detection parameters need to be configured, the configured detection parameters must be consistent with those of the next hop of the routing, a plurality of the next hops need to correspond to a plurality of BFD detections, the BFD messages need to be transmitted periodically, and the shorter the detection time is, the larger the system overhead which is occupied is.

Method and device for link fault detecting and recovering based on ARP interaction


A method of obtaining an image tile from a server by a client includes a client submitting a request to a server for extracting an image tile from a compressed image file. The server controls access to the compressed image file, the compressed image file contains multiple different resolution image layers and the image tile is to be extracted from one of these image layers. The request includes the identity of the image layer and the coordinates of the image tile in the image layer. The server extracts the requested image tile directly from the image layer in the compressed image file using the request and transfers image tile to the client at the decompressed image resolution and quality such that the image tile can be displayed on a display of the client.

Aerial images are used for a variety of purposes such as surveying. Such aerial images are typically captured from an airborne platform such as a drone and then stored on disk (or in the cloud), e.g. in a compressed format. A stored image may then be accessed by a client via a server such that a user of the client machine is able to view the image.
The stored images are typically very large and so when a user of the client machine makes a request for an image, this may require large amounts of data to be transferred from the server to the client in order to download the image, once the requested image has been located by the server. Invariably this takes a long time for the user to receive, and be able to view, the images at the resolution they desire.
One option is to download the whole of a compressed image file from the server to the client and then decompress the image file, before displaying the part of the image the user wishes to view. However, this requires a large amount of data to be downloaded and then decompressed, even though the user may not wish to view the entire image. Both downloading and decompressing the image file takes a finite amount of time which results in a large delay between the image being requested and being able to be viewed. This process can be sped up by the server employing a tile cache, such that tiles of images which have been requested by a client previously are available more readily for downloading subsequently. Furthermore, such image tiles may be decompressed for storing in the cache such that these pre-computed tiles are available for downloading. An extension of this approach is for the server to pre-compute all tiles at all possible resolutions and store them in the tile cache ready for retrieval even before any single tile request has been made.
Another option is to use a streaming protocol (e.g. JPEG 2000 Interactive Protocol (JPIP)) that uses tile evolution. This first downloads a low quality version of the requested image that can be viewed relatively quickly. A higher quality version of the image is also downloaded such that the lower quality image is updated to be displayed in higher quality. However, the higher quality image takes longer to download and so there is still a delay in being able to view the image at the desired quality.


In a capacitor of an analog semiconductor device having a multi-layer dielectric film and a method of manufacturing the same, the multi-layer dielectric film can be readily manufactured, has weak reactivity with corresponding electrodes and offers excellent leakage current characteristics. In order to obtain these advantages, a lower dielectric film having a negative quadratic VCC, an intermediate dielectric film having a positive quadratic VCC, and an upper dielectric film having a negative quadratic VCC are sequentially formed between a lower electrode and an upper electrode. The lower dielectric film and the upper dielectric film may be composed of SiO2. The intermediate dielectric film may be composed of HFO2.

This application claims priority to Korean Patent Application No. 10-2004-0051974, filed on Jul. 5, 2004, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present invention relates to an analog semiconductor device and a method of manufacturing the same, and more particularly, to an analog semiconductor device having a multi-layer dielectric film and a method of manufacturing the same.
2. Description of the Related Art
Analog capacitors are used in analog-to-digital converters (AD converters), RF devices, switching capacitor filters, CMOS image sensors (CISs), and the like. When a voltage applied to an analog capacitor is changed, the electric charge applied to electrodes surrounding a dielectric film is also changed. Analog capacitors retain signal information that is based on the variation of the electric charge.
In general, when a voltage (V) is applied to a capacitor, the electric charge of the electrodes can be expressed by the following equation:Q=C×V,where C denotes an electrostatic capacitance, that is, a capacitance, and V is the voltage.
When the capacitance (C) is constant, the electric charge (Q) is linearly proportional to the voltage (V). When the voltage (V) is constant, the electric charge (Q) of the capacitor is linearly proportional to the capacitance (C). Assuming such a linear relationship, the operating voltage range of the capacitor can be quantized into a plurality of steps and each of the quantized voltages can correspond to a bit of a binary number.
In order to obtain a large number of bits from an analog capacitor, the difference in electric charge corresponding to each of the quantized voltages must be large and constant. Therefore, analog capacitors are composed of a dielectric film having the property of an excellent voltage coefficient of capacitance (VCC). A dielectric film with excellent VCC ensures that, when a voltage is applied to the capacitor, the capacitance is almost constant and is sufficiently large, and that leakage current is small.
High integration of analog semiconductor devices results in the requirement for smaller capacitors. With the smaller size, in order to prevent a decrease of capacitance, a high-k dielectric film is used. In this case, the high-k dielectric film is defined as a dielectric film having a dielectric constant of 8 or greater.
Meanwhile, the capacitance of a capacitor generally depends on applied voltage. That is, the capacitance C(V) is a function of an applied voltage (V). The capacitance C(V) can be expressed as:C(V)=C(0)×(a×V2+b×(V+1)),where C(0) denotes the capacitance of the capacitor at an applied voltage of 0 V, a denotes a quadratic voltage coefficient of capacitance (VCC), and b denotes a linear VCC. Accordingly, in order to have a small VCC, a and b each should be 0 or nearly 0, and in particular, a should be nearly 0.
The quadratic coefficient a depends on interfacial characteristics between the electrodes and the dielectric film of a capacitor. That is, when a voltage is applied, when depletion occurs in the electrodes, the quadratic coefficient a becomes negative. On the other hand, when electrons flow to the dielectric film, thereby decreasing the effective thickness of the dielectric film, the quadratic coefficient a becomes positive.
The dielectric film of an analog capacitor is preferably a high-k dielectric film having a small leakage current and a quadratic VCC a having a small absolute value. However, currently, leakage current characteristics and voltage efficiency characteristics for analog capacitor cannot be satisfied by the use of a single high-k dielectric film.
In order to overcome this problem, multi-layer dielectric films have been employed in the manufacture of analog capacitors. An example of such a capacitor is disclosed in "Capacitor with Multi-component Dielectric and Method of Fabricating the Same" (U.S. Pat. No. 6,341,056), by Allman et. al.
However, in such capacitors, reaction between the multi-component dielectric film with the electrodes needs to be reduced. In addition, an improvement in leakage current characteristics at high temperatures, shortening of the manufacturing process of the multi-layer dielectric film, and prevention of contamination in the multi-layer dielectric film are needed.

Capacitor of analog semiconductor device having multi-layer dielectric film and method of manufacturing the same