A method and apparatus for correcting error modes of a deformable mirror, including selecting or targeting one or more target error modes of a deformable mirror; and designing a pattern and/or shape of one or more electrodes, wherein the pattern and/or shape of the electrodes are designed to optimally correct the target error modes when the electrodes are disposed on the deformable mirror via an active material. Also disclosed is a deformable structure, including a composite shell including a plurality of plies each including carbon fibers embedded in a resin; a nanolaminate comprising individual nanolayers attached to a first side of the composite shell; an actuation structure attached to a second side of the composite shell; and a flexible electrode routing layer attached to the actuation structure.

1. Field of the Invention
This invention relates to a deformable mirrors and a method for fabricating deformable mirrors.
2. Description of the Related Art
(Note: This application references a number of different publications as indicated throughout the specification by one or more reference numbers within brackets, e.g., [x]. A list of these different publications ordered according to these reference numbers can be found below in the section entitled "References." Each of these publications is incorporated by reference herein.)
Deformable mirrors are able to correct the wavefront shape in optical instruments for a variety of applications, including astronomy [1], high-energy lasers [2], microscopy [3], and ophthalmology [4]. Each application has different requirements, in terms of precision of correction and the amplitude, spatial frequency and temporal frequency of the wavefront error to be corrected [5]. There are three basic technologies for deformable mirrors [6]: surface-normal actuation, surface-parallel actuation, and boundary actuation. Surface-normal actuators apply forces perpendicular to the optical surface; an array of push/pull actuators produces local displacements and slopes [7] by reacting against a backing structure. It is an efficient solution to compensate for relatively high spatial frequencies and low amplitude errors. Surface-parallel actuated systems consist of an active material laminated to a mirror face-sheet; the in-plane stretching or contraction of the active material causes the mirror to bend [8-11]. This solution does not require any backing structure and hence is suited to lighter mirrors and to the correction of larger amplitude errors. Alternative implementations have adopted discrete actuators embedded in a lightweighted structure [12]. Systems with boundary actuators use forces and moments along the edge of the mirror to bend the optical surface [13]. This approach minimizes the actuator print-through and is ideal to compensate for low spatial frequency errors with a relatively small number of actuators.
Active primary mirrors in earth-based telescopes have already enabled the emergence of very large apertures [14] and the future development of larger space-based observatories will require novel active primary mirror technologies [15]. Earlier studies [9] have shown that 1 m diameter spherical segments forming a 10 m diameter segmented aperture with a focal length of 10 m would require a correction bandwidth of the order of 250 μm to achieve the required shape in all segments.
Moreover, optical-quality mirrors are heavy, expensive and difficult to manufacture. Traditional mirrors, such as that for the Hubble Space Telescope are made by grinding and polishing a thick slab of near-zero coefficient of thermal expansion (CTE) glass down to nanometer-level precision. Not only is this method difficult and expensive to implement but the areal density of such mirrors is extremely high [31]. Advancements in lightweight mirrors such as those for the James Webb Space Telescope (JWST) have reduced this number greatly [32]. However, as these mirrors must still be polished down to optical-quality tolerances, the associated cost and manufacturing complexity is still too great. Simpler shell-type mirrors constructed using replication techniques are also under development [33-34] however they often suffer from a lack of figure accuracy and surface quality.
Several efforts have also been made to incorporate some level of actuation into the mirror structure. This allows the mirror to 1) correct for any manufacturing figure errors, 2) correct for any errors introduced during operation (i.e. due to thermal variations) and 3) modify its figure in order to accommodate different optical prescriptions. Concepts incorporating a variety of materials and actuation schemes for both thick and shell-type mirrors have been proposed. The most advanced of these is the Actuated Hybrid Mirror (AHM) from AOA Xinetics [35-36]. These structures are made from light-weighted silicon carbide with embedded piezoelectric stack actuators. Mirrors of this design have been demonstrated on large scales (>1 m) and down to optical-quality tolerances (<10 nm RMS). However, they are expensive to produce and their full-scale actuation range is limited as they are still relatively stiff structures. Highly-deformable shell mirrors are also under development [37-38] however they are limited in aperture size and shape accuracy.

Optimized actuators for ultra-thin mirrors


An anamorphic lens attachment to be used in conjunction with a basic lens. The attachment provides a variable anamorphic ratio. The attachment comprises a first lens group having positive refractive power in a first direction, a second lens group having negative refractive power in the first direction, and a third lens group having positive refractive power in the first direction. The second lens group is movably located between the first lens group and the basic lens. The third lens group is located between the second lens group and the basic lens at a fixed distance from the first lens group. The lens groups of the attachment have neutral refractive power in a second direction substantially perpendicular to the first direction.

1. Field of the Invention
This invention relates to an anamorphic attachment to be used in conjunction with a basic lens.
2. Background Information
A picture has an aspect ratio, which is the ratio between the image width and height. Motion pictures were originally recorded on film where the image area had an aspect ratio of 4:3 (1.33:1), sometimes referred to as academy ratio. To accommodate the addition of a soundtrack, the standard ratio for filming was adjusted slightly to be 1.37:1. Television also uses a 4:3 aspect ratio.
To enhance the theatrical cinematic experience, various methods have been devised to present a motion picture that is wider than a 4:3 ratio. Some common presentation formats and the percentage increase in width over academy ratio are as follows:
CinemaScope .RTM. 2.55:1 192% Panavision .RTM. 2.40:1 180% Super 35 2.34:1 177% Flat widescreen U.S. 1.85:1 139% High-definition television 1.78.1 134% Flat widescreen Europe 1.66:1 125%
Presentation of motion pictures with a wide aspect ratio is sometimes accomplished by masking the full frame of the image on the media to be displayed to produce the desired image ratio. This process is often called flat widescreen. While this requires minimum modification to the projector to display a wider image than academy ratio, the object being projected is smaller. This results in a projected image that is not as bright and is of lower quality than an image of the same height projected from the full frame of the display media.
Flat widescreen presentations from film media using modern projectors achieve acceptable quality levels. However, emerging projection technologies for digitally encoded motion pictures use display media that presently cannot provide the resolution of film. The loss of resolution inherent in a flat widescreen process makes masking of the projected object undesirable with such projection technologies.
Another method of presenting a wide motion picture is the anamorphic process. The image to be projected is compressed horizontally to fit in a full frame by using anamorphic optics, or by other means such as electronic image manipulation. The image is then expanded by corresponding anamorphic optics on the projector which provide greater magnification horizontally than vertically to produce the appropriate display aspect ratio. It should be noted that, while it is convenient to speak in terms of compressing when recording and expanding when reproducing along one axis, the same result can be achieved by compressing when recording along one axis and compressing when reproducing along the perpendicular axis. It is also possible to use expansion in both processes rather than compression. Thus, the recording lens may either have a reciprocal anamorphic ratio to the reproducing lens with the anamorphic effect of both applied along the same axis, or both lenses can have the same anamorphic ratio applied along perpendicular axes.
Anamorphic systems produce presentations of a high quality, but the necessity for the additional anamorphic optics increases the cost of the projector. Anamorphic lens attachments generally provide only a single ratio of anamorphic effect. Therefore, a different anamorphic attachment is required to provide the appropriate anamorphic ratio for every format that is to be presented with an anamorphic process.
The use of anamorphic optics to provide a variety of display aspect ratios is particularly beneficial for systems based on emerging digital display technologies because all available resolution of the recording and display media can be utilized. Further, some digital media use ratios other than academy ratio. For example, media with a 1280 by 1024 element resolution has a ratio of 1.25. Without anamorphic optics, a 4:3 ratio image could use only 963 elements vertically, while a 1.85:1 flat widescreen image would use only 692 vertical elements. By using anamorphic optics with an anamorphic ratio of about 1.07:1, a 4:3 ratio image can utilize the full 1024 element vertical resolution.
It would be desirable to use an anamorphic process to display a variety of formats that are wider than academy ratio to enjoy the benefits of brighter images of higher quality without the expense of a large number of anamorphic lens attachments. This is especially desirable for emerging digital projection technologies where all available resolution is needed. Accordingly, there is a need for an anamorphic attachment with a variable anamorphic ratio for use in recording or projecting images with aspect ratios that differ from the aspect ratio of the image area on the recording or display medium.


A method in connection with continuous cooking of chips, comprising impregnation of the chips with impregnation liquid in an impregnation vessel (3) and cooking of the impregnated chips in a digester (4), the impregnation vessel and the digester being connected to each other by means of a transfer circulation, which partly, via a feed line (25), feeds the chips from an outlet end (27) of the impregnation vessel to the top of the digester for separation of free liquid in a separator (28), and partly, via a return line (26), feeds separated liquid from the top of the digester to the outlet end of the impregnation vessel for use as transfer liquid for the impregnated chips, besides which cooking liquid is added to the chips in the top of the digester. According to the invention, as a first part, less than 100%, preferably less than 95% and more preferred less than 90% of the liquid which is separated from the chips in the transfer circulation, is recirculated to be used as transfer liquid.

Environmental demands has forced our industry to develop improved cooking and bleaching methods. One recent breakthrough within the field of cooking is ITC.TM., which was developed in 1992-1993. ITC.TM. is described in WO-9411566, which shows that very good results concerning the pulp quality may be achieved. ITC.TM. is mainly based on using almost the same temperature (relatively low compared to prior art) in all cooking zones in combination with moderate alkaline levels. The ITC.TM.-concept does not merely relate to the equalization of temperatures between different cooking zones, but a considerable contribution of the ITC.TM.-concept relates to enabling an equalized alkaline profile also in the lower part of the counter-current cooking zone.
Moreover, it is known that impregnation with the aid of black liquor can improve the strength properties of the fibers in the pulp produced. The aim of the impregnation is, in the first place, to thoroughly soak each chip so that it becomes susceptible, by penetration and diffusion, to the active cooking chemicals which, in the context of sulphate cellulose, principally consist of sodium hydroxide and sodium sulphide.
If, as is customary according to prior art, a large proportion of the white liquor is supplied in connection with the impregnation, there will exist no distinct border between impregnation and cooking. This leads to difficulties in optimizing the conditions in the transition zone between impregnation and cooking. Now it has been found that surprisingly good results can be achieved when:
1. Keeping a low temperature but a high alkali content in the beginning of a concurrent cooking zone of the digester; PA1 2. Withdrawing a substantial part of a highly alkaline spent liquor that has passed through at least the concurrent cooking zone; and PA1 3. Supplying a substantial portion of the withdrawn spent liquor that has a relatively high amount of rest-alkali, to a point that is adjacent the beginning of an impregnation zone. PA1 a screw feeder having an inlet end and an outlet end for feeding wood chips in an upward direction from the inlet end towards the outlet end of the screw feeder; PA1 a rotatable shaft in operative engagement with the screw feeder; PA1 a drive unit secured to the rotatable shaft for rotating the rotatable shaft; PA1 a cylindrical screen basket enclosing the screw feeder; and PA1 a liquid collecting space enclosing the cylindrical screen basket for separating a substantial portion of a free liquid, the liquid collecting space being in fluid communication with a return line connected to the outlet of the impregnation vessel; and PA1 a distribution means for supplying a cooking liquid to the fiber material, said distribution means being positioned downstream of the collecting space in relation to the flow of the chips.
This leads to a reduced H-factor demand, reduced consumption of cooking chemicals and better heat-economy. Additionally, the novel method leads to production of pulp that has a high quality and a very good bleachability, which means that bleach chemicals and methods can be chosen with a wider variety than before for reaching desired quality targets (brightness, yield, tear-strength, viscosity, etc.) of the finally bleached pulp. This novel process is defined in more detail in our co-pending application PCT/SE97/00192.
The present invention relates to a preferred method and device for practising the above. In connection with the continuous cooking of cellulose containing fibre material, it comprises impregnation of the fibre material with an impregnation liquid in an impregnation vessel and cooking of the impregnated fiber material in a digester, the impregnation vessel and the digester being connected to each other by a transfer circulation, which, via a feed line, feeds the fibre material from an outlet end of the impregnation vessel to the top of the digester, which feed-line comprises a separator for separation of free liquid from the fibre material and, which via a return line, feeds separated liquid back to the outlet end of the impregnation vessel for use as transfer liquid for the impregnated fibre material. Cooking liquid, is added to the fibre material after separation of the free liquid, preferably in connection with the top of the digester, downstream said separation of liquid.
According to conventional technique for withdrawal of liquid from the cooking system, this is normally done directly from the withdrawal strainer of the digester itself. Alternatively in connection with a two vessel system the impregnation vessel, may be supplied with fresh cooking liquor and equipped with a screening device, from which some of the withdrawn liquid is transferred to a recovery plant, possibly after first having passed a flash cyclone. The use of such a screening device involves a considerable cost, due to a special construction of the impregnation vessel being necessary, assembly of conduits and installation of screens, blind plates, nozzles, a possible central line and different instruments in addition to labour for assembling, welding etc. In addition to this there are difficulties in optimizing the withdrawal at this point. Moreover the operating costs of such a screening device is not neglectable. Furthermore the addition of white liquor (fresh cooking liquid) within the impregnation vessel or in the transfer circulation line leads to difficulties in optimizing the process. Firstly when supplying to the impregnation vessel it can be difficult to achieve sufficient mixing of the added white liquor in the impregnation vessel, leading to varying levels of alkaline in different parts. Secondly different kind of wood chips may consume varying amounts of alkaline, making it more difficult to optimize the conditions in the impregnation vessel. It is even claimed that the above might have a bad influence on cost and the quality of pulp, since if a too high amount of alkaline exists in connection with the mechanical action of the outlet scraper might deteriorate fibre strength.
The object of the present invention is to improve and simplify the cooking department with respect to withdrawal and supply of liquid from the cooking system. This is achieved by the use of a new method in connection with a new separator, also leading to a simplified construction of the impregnation vessel with resulting savings in material and costs and to a better way of optimizing withdrawal and supply of liquid thereby also creating conditions for a better utilisation of the cooking liquid.
The device according to the invention is characterised by a separator for wood chips disposed in the feed line between an impregnation vessel and a digester comprising:
According to a further aspect of the invention, less than 100%, preferably less than 95% and more preferred less than 90% of the liquid which is separated from the fibre material in the transfer circulation is recirculated to be used as transfer liquid for the impregnated fibre material and/or to be re-used in connection with the impregnation vessel, either as a transfer liquid or as an impregnation liquid.
Further the apparatus according to the invention is characterised in that it comprises a connection, which stretches from the liquid chamber of the separator to a recovery plant, for withdrawal of a second part of the liquid which is separated by the separator from the cooking system.
According to a preferred embodiment of the invention, the mixture of fibre material and impregnation liquid is fed through the entire impregnation vessel, without liquid being withdrawn from the cooking via the impregnation vessel, besides which a second part of the liquid which is separated in the separator is transferred to recovery.
It is preferred that the second part of the withdrawn liquid is allowed to flash before the recovery.
The second part of the withdrawn liquid may suitably constitute at most 20 m3/ADMT of pulp and at least 0.5 m3/ADMT of pulp, preferably at least 2 m3/ADMT of pulp and more preferred at least 4 m3/ADMT of pulp. It is suitable that liquid is separated from the fibre material in a controlled amount, so that the fibre material contains at least 0.5 m3 free liquid/ADMT of pulp.
According to yet another preferred embodiment of the invention, cooking liquid is added to the separator after separation of liquid in order to be intimately mixed with the fibre material which is poor in liquid, by influence of an upwards feeding screw in the top separator.
The said second part of liquid is suitably withdrawn from said return line via a branch line, directly or indirectly, outside the fibre material to the recovery without any essential part thereof being recirculated to the digester.

Continuous digester system having a top separator


A prosthetic assembly and a method of assembling same. The prosthetic assembly includes a base component with at least one engagement surface. A pyrolytic carbon component includes at least one engagement surface. The pyrolytic carbon component is elastically deformed to mechanically interlock with the engagement surface on the base component. The pyrolytic carbon component retains at least a portion of the deformation stress created during coupling with the base component.

Pyrolytic carbon is a material that has thus far been used to great satisfaction in the field of medical prostheses. One of the interesting properties of pyrolytic carbon is its Young's modulus is close to that of bone as well as its low coefficient of friction. As a result, pyrolytic carbon may work in frictional contact with bone without causing significant wear.
Yet pyrolytic carbon has the drawback of being poorly adapted as component of an assembly. On account of its brittleness it is difficult to attach pyrolytic carbon components using fasteners or welding. Nor can it be drilled as easily as other materials such as metals. For this reason, very few methods have been proposed thus far for joining a pyrolytic carbon component to another component in an assembly.
U.S. Pat. No. 5,458,647 describes an assembly that consists of a pyrolytic carbon cylinder force-fit into a bore in a metal component shorter than the cylinder. In this assembly, the pyrolytic carbon is permanently kept under stress. The danger exists, therefore, that the pyrolytic carbon will break when it is subjected to additional stresses during use. Moreover, the region of the junction between the component of the pyrolytic carbon cylinder engaged in the bore and the component situated outside of the bore constitutes a fragile region that may cause rupture of the pyrolytic carbon.
EP 1 365 165 discloses another type of assembly where a pyrolytic carbon component is shaped as a concave cone into which a convex cone of another component is fitted. One surface of the concave component perpendicular to the axis of the cones is abutting a corresponding surface of the convex component in order to account for the poor tensile strength of pyrolytic carbon, and thus limit the tensile stress of the concave component. This assembly also keeps the pyrolytic carbon permanently under stress. Moreover, the convex and concave cones must have a bearing surface sufficiently long for a good hold of the convex cone within the concave cone, as in all conical couplings. Such an assembly may thus not be realized when the pyrolytic carbon concave component has a small height.
U.S. Pat. No. 5,593,445 discloses a prosthesis with a pyrolytic carbon annular component snap-fit onto a spherical head of a convex component. The spherical head and the pyrolytic carbon annular component are engaged into a shell-shaped concave component. The convex and concave components are made of a titanium alloy or of ceramics. The annular pyrolytic carbon component is free to move on the spherical head but is held onto this head by the snap-fit arrangement. The convex and concave components are articulated like a ball-and-socket joint, and both are able to slide on the annular pyrolytic carbon component placed between them. This assembly of convex and concave components made of a material other than pyrolytic carbon and an intermediate mobile component made of pyrolytic carbon produces important friction, and thus risks of wear.

Method and assembly of a pyrolytic carbon component attached to another component


A support for one or more rolls of sheet stock material includes a sloped support surface for supporting at least one roll, an operating stop toward a lower end of the support surface that defines an operating position at which a stock roll is held for paying out sheet stock material from the roll, and a holding stop. The holding stop extends above the support surface. The holding stop holds one or more rolls at a location spaced from the operating position, and is movable to allow a stock roll to move down the support surface, past the holding stop to the operating position.

In the process of shipping an item from one location to another, protective packaging material is often placed in the shipping container to fill any voids and/or to cushion the item during the shipping process. Paper, which is biodegradable, recyclable and composed of a renewable resource, is a popular source of packaging material for environmentally-conscientious shippers, but other sheet materials also are used to make dunnage products.
Paper and other sheet stock materials often are supplied in a compact roll form for a conversion machine to convert into a relatively lower density dunnage product. The sheet stock material typically is supported on a spindle or axle that passes through the core of the roll with its ends projecting therebeyond for cradled receipt in respective laterally spaced apart spindle supports of a stock roll holder. The spindle supports may be provided, for example, directly on the frame of the cushioning conversion machine or on a mobile cart as shown in U.S. Pat. No. 5,123,889.
A stock roll typically is loaded from a position on the floor. An axle rod is inserted through a hollow core at the center of the stock roll, and the stock roll is then raised by grasping and lifting the ends of the axle rod where it projects from opposite ends of the stock roll. The loading operation is completed by lowering the projecting ends of the axle rod onto the laterally spaced apart spindle supports that have recesses for cradled receipt and retention of the axle rod.
The conversion machine generally is disposed above the floor, sometimes at or above head level, which makes loading a stock roll more difficult because of the greater height to which the stock roll must be lifted. Also, the machine may be positioned over a conveyor which may require the operator to reach over the conveyor when loading a stock roll. Moreover, in some installations a person other than the machine operator may be designated to lift and load stock rolls. In these situations, delay may arise when such person, or attendant, is not immediately available. Consequently, the operator must wait until such an attendant is available. The delay may be of considerable length when the attendant is busy with another task, such as loading a stock roll for another machine or machines.

Dunnage conversion machine and method with sequential stock roll storage and loading


A memory device includes a memory element, a first wiring and a second wiring. The memory element includes a memory layer retaining information based on a magnetization state of a magnetic material and a magnetization pinned layer in which a magnetization direction is pinned and which is provided for the memory layer through a non-magnetic layer, in which current flows in a stacking direction to change a magnetization direction of the memory layer. The first wiring supplies current flowing in the stacking direction of the memory element, and the second wiring supplies current to apply a current magnetic field to the memory element. When information is recorded in the memory device, a first pulse current is supplied to the first wiring, a second pulse current is supplied to the second wiring, and the second pulse current falls at least 10 picoseconds after the first pulse current falls.

The present application relates to a memory device that includes a memory element having a memory layer which stores a magnetization state of a magnetic material as information and a magnetization pinned layer in which a magnetization direction is pinned. A magnetization direction of the memory layer is changed by supplying current, and the memory device is suitably applied to a nonvolatile memory.
Since information communicating apparatuses, in particular, small-sized apparatuses for personal use such as portable communication terminals have been widely used, further high performance such as higher integration, higher operation speed and lower electric power usage is requested for a memory element, logic element or the like included in such apparatuses.
Specifically, a nonvolatile memory may be a necessary component for highly-functional apparatuses.
As a nonvolatile memory, a semiconductor flash memory, FeRAM (Ferroelectric Random Access Memory) or the like has been used and further research and development have been carried out for higher performance.
Lately, as a nonvolatile memory using a magnetic material, MRAM (Magnetic Random Access Memory) using tunnel magneto-resistance effects has been developed and attracting attention (for example, refer to "J. Nahas et al., IEEE/ISSCC 2004 Visulas Supplement, p. 22").
MRAM includes regularly-arranged minute memory elements in which information is recorded and wiring such as a word line and a bit line provided to access each of the memory element.
Each magnetic memory element is configured to have a memory layer in which information is recorded as a magnetization direction of a ferromagnetic material.
The magnetic memory element employs a structure using MTJ (Magnetic Tunnel Junction), including the above-described memory layer, a tunnel insulating film (non-magnetic spacer) and a magnetization pinned layer where a magnetization direction is pinned. The magnetization direction of the magnetization pinned layer may be pinned by providing an anti-ferromagnetic layer, for example.
In such structure, a tunnel magneto-resistance effect is caused, in which a resistance value to tunnel current flowing through a tunnel insulating film changes in accordance with an angle between the magnetization direction of the memory layer and the magnetization direction of the magnetization pinned layer. Accordingly, information is written (recorded) using the tunnel magneto-resistance effect. The resistance value becomes maximum when the magnetization direction of the memory layer and the magnetization direction of the magnetization pinned layer are anti-parallel, and becomes minimum when these are parallel.
Information is written (recorded) to the above-described magnetic memory element by controlling a magnetization direction of the memory layer in the magnetic memory element using a combined current magnetic field caused by supplying current to both of a word line and a bit line. Typically, magnetization directions are stored corresponding to information "0" and information "1", respectively.
Japanese Unexamined Patent Application Publication No. H10-116490, for example, discloses a method using an asteroid characteristic, and U.S. Patent Application Publication No. 2003/0072174, for example, discloses a method using a switching characteristic, in order to record information into the memory element.
On the other hand, in order to read recorded information, the recorded information may be detected by detecting a difference between the magnetization directions of the memory layer as a difference between voltage signals using the tunnel magneto-resistance effect of the magnetic memory element after a memory cell is selected using an element such as a transistor.
MRAM has such an advantage that the information "0" and information "1" are rewritten by inverting the magnetization direction of the memory layer formed of a ferromagnetic material and therefore information can be rewritten at high speed and without a limit of times (>1015 times) as compared with other nonvolatile memories.
However, a comparatively intensive current magnetic field may be required for MRAM in order to rewrite recorded information. Therefore, a certain amount of current (for example, several mA to several tens mA) may need to be applied to address wirings. Thus, power consumption may be large.
Further, MRAM may require address wiring for the writing and address wiring for the reading separately, and therefore it is difficult for a memory cell to be miniaturized.
Furthermore, with a memory element miniaturized, such problems as described below may occur. Accordingly, address wiring becomes thin and it is difficult to apply a sufficient amount of current thereto, and power consumption increases due to the intensive current magnetic field required for large coercive force.
Therefore, it has been difficult to miniaturize the element.
U.S. Pat. No. 5,695,864, for example, discloses a method for coping with such problems, in which recording without using a current magnetic field is studied and, in particular, a memory that uses magnetization inversion based on spin-transfer attracts attention as a configuration in which the magnetization direction can be inverted with less current.
Japanese Unexamined Patent Application Publication No. 2003-17782, for example, discloses magnetization inversion based on spin-transfer, in which electrons passing through a magnetic material and being spin-polarized are injected into other magnetic materials to cause the magnetization inversion.
Specifically, when spin-polarized electrons passing through a magnetic layer where a magnetization direction is pinned (magnetization pinned layer) enter another magnetic layer where magnetization direction is not pinned (magnetization free layer), spin-transfer torque is given to magnetization of the magnetization free layer. When current of a threshold value or more flows, the magnetization direction of the magnetic layer (magnetization free layer) may be inverted.
For example, if current is applied in the direction perpendicular to a film surface of a great magneto-resistance effect element (GMR element) or of a magnetic tunnel junction element (MTJ element) which includes a magnetization pinned layer and a magnetization free layer, the magnetization direction of at least a part of the magnetic layers of those elements may be inverted.
Accordingly, a memory element including a magnetization pinned layer and a magnetization free layer (memory layer) is formed, in which a polarity of current flowing through the memory element is changed to invert a magnetization direction of the memory layer, thereby rewriting information "0" and information "1".
A tunnel magneto-resistance effect is used similarly to MRAM by providing a tunnel insulating layer between the magnetization pinned layer and the magnetization free layer (memory layer), thereby reading recorded information.
Magnetization inversion by spin-transfer has an advantage that the magnetization inversion may be realized without increasing an amount of current even though an element is reduced in size.
An absolute value of current flowing through the memory element to cause the magnetization inversion is 1 mA or less in the memory element of about 0.1 μm, for example, and the absolute value is reduced in proportion to a volume of the memory element, which is advantageous in scaling.
Further, since a recording word line that is necessary for MRAM is unnecessary, there is such an advantage that a configuration of a memory cell is simplified.
A memory element using spin-transfer is hereinafter called SpRAM (Spin-transfer Random Access Memory) and spin-polarized current that causes the spin-transfer is called spin injection current.
SpRAM is expected as a nonvolatile memory consuming less electric power and having large capacity while keeping advantages of MRAM that operates at high speed and can be rewritten without a limit of times.
FIG. 1 is a schematic sectional view showing a memory cell in a memory (SpRAM) that uses typical spin-transfer.
A diode or MOS transistor or the like may be used to electrically select a memory cell in order to read information recorded in the memory cell. The memory cell shown in FIG. 1 uses a MOS transistor.
First, a configuration of a memory element 101 forming a memory cell of SpRAM is described.
An anti-ferromagnetic bond is formed between a first magnetization pinned layer 112 and a second magnetization pinned layer 114 through a non-magnetic layer 113. Further, the first magnetization pinned layer 112 is provided in contact with an anti-ferromagnetic layer 111 and has a strong unidirectional magnetic anisotropy caused by exchange interaction between the layers. A pinned layer 102 is configured to have the four layers 111, 112, 113 and 114. Specifically, the pinned layer 102 includes two magnetic layers (first magnetization pinned layer 112 and second magnetization pinned layer 114).
A ferromagnetic layer 116 is configured such that a direction of magnetization M1 is inverted comparatively easily to form a memory layer (magnetization free layer) 103.
A tunnel insulating layer 115 is formed between the second magnetization pinned layer 114 and the ferromagnetic layer 116, specifically, between the pinned layer 102 and the memory layer (magnetization free layer) 103. The tunnel insulating layer 115 disconnects a magnetic bond between the magnetic layers 116 and 114 stacked in a vertical direction and supplies tunnel current. Thus, a TMR (tunnel magneto-resistance) element is configured to have the pinned layer 102 in which the magnetization directions of the magnetic layers are pinned, the tunnel insulating layer 115 and the memory layer (magnetization free layer) 103 in which the magnetization direction can be changed.
Thus, the memory element 101 includes each of the layers 111 to 116 as described above, a ground layer 110 and a topcoat layer 117 to form the TMR element.
A selection MOS transistor 121 is formed in a silicon substrate 120, and a connecting plug 107 is formed on a diffusion layer 123 that is one of diffusion layers provided for the selection MOS transistor 121. The ground layer 110 of the memory element 101 is provided on the connecting plug 107 to be connected thereto. The other diffusion layer 122 of the selection MOS transistor 121 is connected to a sense line through the connecting plug, although not shown in FIG. 1. A gate 106 of the selection MOS transistor 106 is connected to a selective signal line.
The topcoat layer 117 in the memory element 101 is connected to a bit line (BL) 105 provided on top thereof.
In a steady state, magnetization M11 of the first magnetization pinned layer 112 and magnetization M12 of the second magnetization pinned layer 114 are in almost a perfect anti-parallel state based on a strong anti-ferromagnetic bond through the non-magnetic layer 113.
Typically, the first magnetization pinned layer 112 and the second magnetization pinned layer 114 are configured to have equal products of saturation magnetization and film thickness, and therefore a leakage component of a magnetic pole and magnetic field is sufficiently small to be negligible.
A resistance value of TMR element including the layers 114, 115 and 116 is changed depending on whether the direction of magnetization M1 of the ferromagnetic layer 116 that is the memory layer 103 and the direction of magnetization M12 of the second magnetization pinned layer 114 included in the pinned layer 102 are in a parallel state or an anti-parallel state through the tunnel insulating layer 115. The resistance value is low if two of the magnetizations M1, M12 are in the parallel state and the resistance value is high if these are in the anti-parallel state. A whole resistance value of the memory element 101 also changes when the resistance value of TMR element (layers 114, 115, and 116) is changed. Information can be recorded and the recorded information can be read using the above described changes. Specifically, a state where the resistance value is low is assigned to information "0", for example, and a state where the resistance value is high is assigned to information "1", thereby binary (1 bit) information being recorded.
In order to rewrite information in the memory cell and to read information recorded in the memory cell, it may be necessary to supply spin injection current Iz. The spin injection current Iz passes through the memory element 101, the diffusion layer 123 and the bit line 105.
A direction of the spin injection current Iz flowing through the memory element 101 may be changed from an upward direction to a downward direction, or vice versa, by changing a polarity of the spin injection current Iz.
Accordingly, information in the memory cell may be rewritten by changing the direction of magnetization M1 of the memory layer 103 in the memory element 101.
Japanese Unexamined Patent Application Publication No. 2005-277147 discloses a configuration of SpRAM in which not only spin injection current is supplied to the memory element, but also a bias current magnetic field is applied to the memory element and other elements, in order to invert magnetization direction of a memory layer in a memory element.
Specifically, for example, in a configuration shown in FIG. 1, spin injection current Iz is supplied to a memory element 101 through a bit line 105, and a bias current magnetic field Hx (not shown) caused by current flowing in the bit line 105 (equal to the spin injection current Iz) is applied to the memory layer 103 in the memory element 101.
Thus, a direction of magnetization M1 of the memory layer 103 can be changed efficiently.
A diagram showing a state of a memory cell is hereinafter called a phase diagram in which a vertical axis represents spin injection current Iz and a horizontal axis represents a bias current magnetic field Hx. Here, the phase diagram is prepared using a peak value of pulse current, in the case of using pulse current as bias current that causes spin injection current Iz and a bias current magnetic field Hx.
FIG. 2 shows an example of an apparatus that measures values for a phase diagram of SpRAM. The apparatus shown in FIG. 2 uses a Helmholtz coil 72 instead of a bit line to generate a bias current magnetic field Hx, and bias current Ib flowing in the Helmholtz coil 72 is supplied independently from an external power supply 71.
The spin injection current Iz flows from or flows out to another driving circuit through the bit line 105 connected to the memory cell.
A direction of magnetization M1 of the ferromagnetic layer 116 that is the memory layer 103 may be changed with the spin injection current Iz and bias current magnetic field Hx.
Using the apparatus shown in FIG. 2, intensity and phase of the spin injection current Iz and bias current magnetic field Hx may optionally be set and values for a phase diagram may be measured.
As described above, in a typical SpRAM, information in the memory cell is rewritten by changing a polarity of the spin injection current Iz. However, there is a case in which a result of magnetization inversion (inverted, or not inverted) may not necessarily be determined with a polarity of the spin injection current alone due to instability in the magnetization inversion phenomenon using spin-transfer.
In such case, in order to securely invert magnetization, an auxiliary bias magnetic field may be needed.
However, when spin injection current Iz and a bias current magnetic field Hx are generated using the same bit line as proposed in Japanese Unexamined Patent Application Publication No. 2005-277147, intensity and phases of the spin injection current Iz and the bias current magnetic field Hx may not be set independently. For example, intensity of the spin injection current and intensity of the bias current may not be adjusted independently and optionally, and timing of the spin injection current, timing for applying the bias magnetic field and a polarity thereof may not be adjusted independently.
Therefore, in a typical SpRAM including a configuration proposed in Japanese Unexamined Patent Application Publication No. 2005-277147, since a condition in the case of rewriting information in a memory cell is restricted, for example, it is difficult to optimize the condition so that electric power consumption may be minimized and the rewriting may be performed at high speed.
Further, instability in the above-described magnetization inversion phenomenon using spin-transfer may not be sufficiently prevented, because the condition in the case of rewriting information in a memory cell is restricted.
Here, FIG. 3A shows the case in which a configuration proposed in Japanese Unexamined Patent Application Publication No. 2005-277147 is applied to a memory cell shown in FIG. 1, and shows each timing of pulse current of spin injection current Iz and of pulse current of bias current Ib that generates a bias current magnetic field.
As shown in FIG. 3A, both of spin injection current Iz and bias current Ib have rectangular pulses in order to simplify an explanation. t0 shows an initial condition; t1 and t2 show the time of the spin injection current Iz and bias current Ib rising respectively; and t3 and t4 show the time of the spin injection current Iz and bias current Ib falling respectively; and ts shows the time at which a finished condition is observed.
Duration of each pulse is t3−t1 for the spin injection current Iz and is t4−t2 for bias current Ib. The spin injection current Iz is switched off before t1, and is switched on at t1, and is switched off at t3.
In such case, part of current flowing through the bit line 105 is used as spin injection current Iz and the other is used as bias current Ib to generate a bias current magnetic field Hx. Therefore, the spin injection current Iz and the bias current Ib are supplied to the bit line 105 from the same driving power supply, and so the injection current Iz and the bias current Ib may not be applied at a different timing.
Consequently, time t1 of rising 91 in a pulse of the spin injection current Iz and time t2 of rising 92 in a pulse of the bias current Ib will surely be the same time.
Subsequently, FIGS. 3B and 3C show examples of change in electric resistance of the memory element 101 over time when a typical SpRAM is used. Two curves in FIGS. 3B and 3C correspond to spin injection current Iz ±2.5 mA that exceeds a threshold value for inverting a magnetization direction, respectively. Here, duration (t3−t1 in FIG. 3A) for a pulse of the spin injection current Iz is 5 ns (nanoseconds) and a peak value of a pulse of the bias current Ib is zero. Also, t5−t1 in FIG. 3A is 10 ns.
FIG. 3B shows an example in which an initial resistance is started from a low resistance state ("0" state) and a magnetization direction can be normally inverted.
As shown in FIG. 3B, a high resistance state inverted from the initial state (a low resistance state) can be obtained under a condition where a peak value of spin injection current Iz is −2.5 mA, and a low resistance state remains unchanged as the initial state under a condition where a peak value of spin injection current Iz is +2.5 mA.
On the other hand, FIG. 3C shows an example in which an initial resistance is started from a high resistance state (state "1") and magnetization direction may not be inverted.
As shown in FIG. 3C, a low resistance state inverted from an initial state is temporarily obtained under a condition where a peak value of spin injection current Iz is +2.5 mA; however, the resistance state returns to the original high resistance state when the spin injection current Iz is turned off after passing 5 ns, and a high resistance state remains unchanged as the initial state under a condition where a peak value of spin injection current Iz is −2.5 mA.
A phenomenon in which switching from a high resistance as an initial resistance shown in FIG. 3C may not be inverted normally is observed in the following cases. Specifically, in the case where magnetization M1 of the memory layer (magnetization free layer) 103 does not reach a parallel state due to short duration for spin injection current Iz, in the case where an inverse magnetic domain is generated in a part of the magnetization free layer 103 in a switching process where a magnetization direction changes, or in the case where magnetization M11 or M12 of the pinned layer 102 that may not change basically moves a little by huge spin torque.
Spin torque tends to increase along a current magnetic field in spiral shape formed by the spin injection current Iz, and therefore an inverse magnetic domain of a pattern that resists the current magnetic field in spiral shape formed by the spin injection current Iz is formed in a magnetization free layer 103.
SpRAM is an excellent memory in which current (inversion threshold current) necessary for inverting a magnetization direction of a memory layer can be reduced using spin torque, and intensity of spin torque is huge that easily exceeds torque caused by a static magnetic field which increases in inverse proportion to the size of an element.
Thus, SpRAM has a characteristic that if the size of an element is small, it is advantageous to obtain more inversion threshold current; however, the huge spin torque may cause instability in a spin-transfer magnetization inversion phenomenon. With such instability, a phenomenon in which a magnetization direction may not be inverted by a polarity of the spin injection current alone is observed, as shown in FIG. 3C.
Next, a relationship between the above-described phenomenon and a phase diagram is explained.
A typical phase diagram includes: a hysteresis area 80; an area 81 where a memory cell is in "0" state (low resistance state) regardless of an initial magnetization state; an area 82 where a memory cell is in "1" state (high resistance state) regardless of an initial magnetization state; and an unstable operation area 83 where the above-described three areas coexist.
In order to function as a memory in which SpRAM has a realistic margin (operating margin), three areas (hysteresis area 80, "0" state area 81 and "1" state area 82) may need to independently exist as sufficiently wide areas respectively.
As shown in FIG. 3C, a phenomenon in which a magnetization direction may not normally be inverted by a polarity of spin injection current Iz alone appears on a phase diagram as an unstable operation area 83 where two or more states coexist in the "0" state area 81 and in the "1" state area 82.
FIG. 4 shows an example of a measured phase diagram of a typical SpRAM in which duration of spin injection current Iz and that of bias current Ib are 5 ns.
The phase diagram shown in FIG. 4 is a diagram showing a state of a memory cell in a switching finished condition (for example, t5 in FIG. 3A) with a peak value of a pulse of spin injection current Iz as a vertical axis and a peak value of a pulse of a bias current magnetic field Hx as a horizontal axis.
As shown in FIG. 4, the unstable operation area 83 where the three states 80, 81, 82 coexist appears upper right in the figure (first quadrant) and lower left in the figure (third quadrant).
It should be noted that the "0" state area 81 appears on the second quadrant, the "1" state area 82 appears on the fourth quadrant and the unstable operation area 83 appears on the first and third quadrants in FIG. 4, however, these are not necessarily universal characteristics. Depending on a method of defining the direction of spin injection current Iz and the directions of magnetization M11 and magnetization M12 of the pinned layer 102, the "0" state area 81, the "1" state area 82 and the unstable operation area 83 may appear on different quadrants from those shown in FIG. 4.
In the case where the unstable operation area 83 appears in the phase diagram as shown in FIG. 4, spin injection current Iz and bias current Ib when performing magnetization inversion may need to be set to the outside of the unstable operation area 83.
However, it may be difficult to set current so as not to be in the unstable operation area 83 in such a configuration that the currents Iz, Ib are supplied from the same bit line.


An apparatus and method improving effective system throughput for replication of data over a network in a storage computing environment by using software components to perform data compression is disclosed. Software compression support is determined between applications in a data storage computing environment. If supported, compression parameters are negotiated for a communication session between storage systems over a network. Effective system throughput is improved since the size of a compressed lost data packet is less than the size of an uncompressed data packet when a lost packet needs to be retransmitted in a transmission window.

A storage system, which also may be known as a filer or a file server, is a computer that provides file services relating to the organization of information on storage media such as disks. The storage system includes a storage operating system that implements a file system to logically organize the information as a hierarchical structure of directories and files on the disks. Each "on-disk" file may be implemented as a set of disk blocks configured to store information, whereas the directory may be implemented as a specially-formatted file in that information about other files and directories are stored.
Storage systems may issue packets using file-based access protocols, such as the Common Internet File System (CIFS) protocol or Network File System (NFS) protocol, over the Transmission Control Protocol/Internet Protocol (TCP/IP) when accessing information in the form of files and directories. Alternatively, storage systems may issue packets including block-based access protocols, such as the Small Computer Systems Interface (SCSI) protocol encapsulated over TCP (iSCSI) and SCSI encapsulated over Fibre Channel (FCP), when accessing information in the form of blocks.
A common type of file system for a storage system is a write in-place file system, in which the locations of the data structures (such as Modes and data blocks) on disk are typically fixed. An Mode may be a data structure used to store information, such as metadata, about a file, whereas the data blocks are structures used to store the actual data for the file. The information contained in an Mode may include information relating to: ownership of the file, access permissions for the file, the size of the file, the file type, and references to locations on disk of the data blocks for the file. The references to the locations of the file data are provided by pointers, which may further reference indirect blocks that, in turn, reference the data blocks, depending upon the quantity of data in the file. Changes to the Modes and data blocks are made "in-place" in accordance with the write in-place file system. If an update to a file extends the quantity of data for the file, an additional data block is allocated and the appropriate Mode is updated to reference that data block.
Another type of file system is a write-anywhere file system that does not overwrite data on disks. If a data block on disk is read from disk into memory and "dirtied" with new data, the data block is written to a new location on the disk to optimize write performance. A write-anywhere file system may initially assume an optimal layout, such that the data is substantially contiguously arranged on the disks. The optimal disk layout results in efficient access operations, particularly for sequential read operations. A particular example of a write-anywhere file system is the Write Anywhere File Layout (WAFL®) file system available from Network Appliance, Inc. The WAFL file system may be implemented within a microkernel as part of the overall protocol stack of the storage system and associated disk storage. This microkernel may be supplied as part of the storage operating system.
A storage operating system generally refers to the computer-executable code operable on a storage system that manages data access. The storage operating system may, in case of a filer, implement file system semantics, such as the Data ONTAP® storage operating system provided by Network Appliance, Inc., of Sunnyvale, Calif. The storage operating system may also be implemented as an application program operating on a general-purpose operating system, such as UNIX® or Windows®, or as a general-purpose operating system with configurable functionality, which is configured for storage applications.
Disk storage may be implemented as one or more storage volumes that comprise physical storage disks, defining an overall logical arrangement of storage space. Currently available storage system implementations can serve a large number of discrete volumes. Each volume may be associated with its own file system.
The disks within a volume may be organized as a Redundant Array of Independent (or Inexpensive) Disks (RAID). RAID implementations enhance the reliability and integrity of data storage through the writing of data "stripes" across a given number of physical disks in the RAID group, and the appropriate storing of parity information with respect to the striped data. In the example of the WAFL® file system, a RAID 4 implementation is advantageously employed, which entails striping data across a group of disks, and storing parity (a data protection value) on a separate disk in the RAID group. A volume typically comprises at least one data disk and one associated parity disk (or possibly data/parity) partitions in a single disk arranged according to a RAID 4, or equivalent high-reliability, implementation. A person of ordinary skill in the art would understand that other RAID implementations can be used, such as RAID-5, RAID-DP, as desired.
A storage system may mirror (i.e. replicate), distribute, or exchange large amounts of data to another storage system across a network. A network may be a local area network (LAN), a wide area network (WAN), the Internet, a wired network, a wireless network, or a computer bus, as desired. The replication of data may be needed for disaster recovery or data distribution, as desired. Since storage systems may each be in different, remote, geographical locations, high latency (i.e. delay) occurs and some data packets may be lost when data is communicated across a network. An undesirable effect of the high latency and lost packets is a decrease in effective system throughput, or data rate, over a network when moving data between storage systems. Effective system throughput decreases since lost packets in a time or transmission window are typically retransmitted by a storage system until they are successfully received by a second storage system across a network. A transmission window may be a maximum amount of data a storage system may receive within a predetermined time frame.
To improve system throughput and overall link utilization, storage systems may use data compression. Conventional storage systems require additional hardware adapters for data compression. The additional hardware results in various incompatible hardware configurations for supporting compression between storage systems.
Therefore, a need exists for exchanging large amounts of data between storage systems across a network while maintaining a high data rate without the undesirable need for additional hardware.

Data replication network traffic compression


The present disclosure relates to image processing devices and methods image processing devices and methods that can reduce noise that is recognized in synchronization with an intraframe appearance cycle.

Moving image encoding normally involves intraframes for intra-frame encoding, and interframes for inter-frame prediction. Intraframes are normally set every 0.5 to several seconds, and the remaining frames are encoded as interframes. When an interframe is encoded, an intraframe or another interframe is used as a reference destination in inter-frame prediction.
Cyclic noise is sometimes caused by such moving image encoding, and the noise is normally called heartbeat noise. Heartbeat noise is noise that is recognized in synchronization with the intraframe appearance cycle, and, because of the heartbeat noise, an image appears to be changing in a constant cycle. Heartbeat noise tends to be generated more often at locations where there are few moving objects, there is little panning of a camera or the like, and inter-frame prediction is valid in interframes.
For example, after an intraframe appears in the first cycle, encoding that does not involve transmission of DCT coefficients, or skipping, is employed with inter-frame prediction. As for the intraframe that appears in the next cycle, encoding that does not involve transmission of DCT coefficients, or skipping, is also employed with inter-frame prediction.
In a case where images subjected to such encoding are viewed, a visual gap is sometimes felt between an inter-frame predicted image group 1 after the intraframe that appears in the first cycle and an inter-frame predicted image group 2 after the intraframe that appears in the next cycle. The subjective image degradation due to this gap is the heartbeat noise described herein.
As a technique for reducing this heartbeat noise, there is a technique for reducing the above described visual gap between the predicted image group 1 and the predicted image group 2 with a smoothing filter. For example, the technique disclosed in Patent Document 1 is a method of removing grain noise that overlaps images captured by a camera or the like, and this method can also be used on heartbeat noise.

Reducing noise in an intraframe appearance cycle

Abstract: At time t0, the respective pixels are copied from the image that is output at the previous time, and only the pixels denoted by Δ among the pixels in a replacement pattern are replaced. At time t1, the respective pixels are copied from the image that is output at the previous time t0, and only the pixels denoted by X among the pixels in the replacement pattern are replaced. At this point, all the pixels in the image have been replaced with a decoded image. That is, by time t1, which is one time before the time when the decoded image is an intraframe, all the pixels in the image are replaced with the decoded image. The present disclosure can be applied to image processing devices, for example.


The present invention is a method for the production of a water absorbent resin, which comprises preparing a monomer component possessing an ability to form a cross-linked structure and convert itself into a hydrated gel polymer during the course of aqueous solution polymerization, possessing an acid group-containing monomer content of at least 50 mol %, and having 10 to 50 mol % of said acid group-containing monomer neutralized and subjecting said monomer component to aqueous solution polymerization within a reaction vessel having a plurality of rotary shafts each fitted with stirring blades.

1. Field of the Invention:
This invention relates to a method for the production of a water absorbent resin. More particularly, it relates to a method for the production of a water absorbent resin which is excellent in absorption properties.
2. Description of the Prior Art:
As water absorbent resins obtainable by the polymerization of a monomer, cross-linked polyacrylates, saponified acrylic ester-vinyl acetate copolymers, modified cross-linked polyvinyl alcohols, partially neutralized cross-linked polyacrylates, cross-linked isobutylene-maleic anhydride copolymers, and starch-acrylic acid graft copolymer have been known in the art. They are extensively utilized as sanitary absorbents such as sanitary napkins and disposable diapers and as water-retaining agents, dehydrating agents, etc. in the field of agriculture and horticulture and in the field of civil engineering, for example.
Among various methods heretofore available for the production of such water absorbent resins, there resorting to the principle of reverse phase suspension polymerization are disclosed in Japanese Patent Laid-Opens SHO Nos. 56(1981)-161,408, SHO 57(1982)-94,011, SHO 57(1982)-158,209, and SHO 57(1982)-198,714, for example, and those resorting to the principle of aqueous solution polymerization are disclosed in Japanese Patent Laid-Open SHO No. 57(1982)-34,101, Japanese Patent Publication SHO No. 48(1973)-42,466, Japanese Patent Laid-Open SHO No. 58(1983)-49,714, Japanese Patent Publication SHO No. 59(1984)-37,003, U.S. Pat. Nos. 4,286,082, and 4,625,001, for example.
The method of reverse phase suspension polymerization necessitates use of an organic solvent and, therefore, entails disadvantages that the organic solvent not only impair the working environment but also threaten explosion due to flashing. Measures must be taken against these disadvantages. The measures render the operation of reverse phase suspension polymerization expensive together with the expense of the organic solvent itself and the expense for the removal of spent solvent. Further, it has a drawback that since the restriction imposed on solid concentration, the productivity of the operation is degraded. Since this organic solvent tends to remain, though in a minute amount, in the product of reverse phase suspension polymerization, an attempt at ensuring perfect removal of the residual organic solvent from the product renders the method all the more expensive. Moreover, since the absorbent resin produced by the method of reverse phase suspension polymerization is in the form of beads of an unduly small diameter, the resin beads used in disposable diaper, for example, have the possibility of falling off the fibrous absorbent core component such as pulp. This resin suffers inconvenience in handling from the fact that it is in the form of minute beads. Further, the method of reverse phase suspension polymerization entails the disadvantage that when the cross-linking agent of insufficient hydrophilicity is used, this cross-linking agent tends to dissolve out in the hydrophobic organic solvent. Though it is possible to increase the solubility of the cross-linking agent in an aqueous monomer solution by the decrease of the neutralization degree of the monomer solution, when this case, it has a problem that the acid group-containing monomer tend to dissolve out in the hydrophobic organic solvent and induce flocculation.
The method of aqueous solution polymerization suffers from none of the drawbacks mentioned above. Particularly the methods disclosed in Japanese Patent Laid-Open SHO No. 57(1982)-34,101 and U.S. Pat. No. 4,625,001 are those for producing a cross-linked polymer by a procedure which comprises effecting radical aqueous solution polymerization of the aqueous solution of a monomer capable of forming a cross-linked structure in the molecular unit thereof on exposure to aqueous solution polymerization and consequently converting itself into a hydrated gel polymer in combination, with a polymerization initiator in a reaction vessel provided with stirring blades by finely dividing the hydrated gel polymer produced in consequence of the progress of the polymerization with the shearing force of the stirring blades generated by the rotation of the stirring shaft. According to these methods, they enjoy extremely high operational efficiency and also have an advantage that finely divided hydrated gel polymer possessing a cross-linked structure in the molecular unit thereof can be produced with ease. Even in these methods of such characteristic features, it has possibility that the production of an absorbent resin exhibiting a high capacity for absorption and containing water solubles in a small amount is difficult.
It is widely known to persons skilled in the art that the ratio of absorption of a given resin is increased by lowering the density of cross-linking. It is also well known that when a water absorbent resin is produced by a procedure capable of lowering the cross-linking density, the produced water absorbent resin suffers from an increase in the content of water solubles. The water solubles are of such nature that when the water absorbent resin forms a hydrogel structure on contact with various liquids such as water, urine, and body fluid, they are exuded through the hydrogel structure. The water solubles which are thus extracted by the liquids subjected to absorption not only degrades the water absorbent resin's ratio of absorption but also accelerates the deterioration of the water absorbent resin. Moreover, the viscid consistency of the water solubles gives birth to a disadvantage that it excites an unpleasant sensation in the human skin and smears the liquid subjected to absorption.
In the circumstances, the desirability of perfecting a method for the production of a water absorbent resin enjoying a high ratio of absorption and containing water solubles only in a small amount has been finding growing approval. U.S. Pat. No. 4,654,039 discloses a method for producing a water absorbent resin enjoying a high ratio of absorption and containing water insolubles only in a small amount by subjecting a substantially free acid type monomer to aqueous solution polymerization. It has been demonstrated, however, that when an unneutralized monomer is polymerized by the use of a conventional radical polymerization initiator, the amount of residual monomer increases in the produced polymer. Naturally, the increase in the amount of residual monomer is nothing to be desired from the standpoint of safety.
An object of this invention, therefore, is to provide a novel method for the production of a water absorbent resin.
Another object of this invention is to provide a method for the production of a water absorbent resin excelling in absorption properties and containing an residual monomer only in a small amount.

Method for production of water absorbent resin


In some embodiments, the invention involves multiple integrated circuit stubs coupled in series. At least one of the integrated circuit stubs including first conductors to receive signals from a first adjacent one of the integrated circuit stubs, second conductors to provide signals to a second adjacent one of the integrated circuit stubs, and third conductors to provide signals to an integrated circuit chip. The integrated circuit stubs include first drivers and second drivers coupled to the first, second, and third conductors, wherein the first drivers receive the external signals from the first conductors and drive them onto the second conductors and the second drivers receive signals from the first conductors and drive them onto the third conductors.

1. Technical Field of the Invention
The present invention relates to integrated circuits and, more particularly, use of active integrated circuit stubs in a point-to-point system of integrated circuits.
2. Background Art
FIG. 1 illustrates a system 10 of integrated circuits including integrated circuits IC0, IC1, IC2 . . . ICn. The integrated circuits are connected through a bus 16. Integrated circuit IC0 may be a controller to control IC1, IC2 . . . ICn or can be the same as them or can be the same as other integrated circuits or can be different. System 10 may be a system that is referred to as multi-drop system in which one or more of integrated circuits IC1, IC2 . . . ICn are selectively joined to bus 16 through stubs 18-1, 18-2, . . . 18-n, respectively. Merely as an example, system 10 may be a memory system in which controller 14 is a memory controller (either joined with a processor on chip or in a different chip from the processor) and in which integrated circuits IC1, IC2 . . . ICn are, for example, dynamic random access memory (DRAM) chips that are on one or more printed circuit boards (PCBs). They could also be in a multi-processor system.
Address, data, and control bits on bus 14, may be on separate conductors of bus 14 or they may be, for example, time division multiplexed or packetized. For example, bus 14 may include some conductors used to carry only address bits, some conductors used only to carry only control bits, and some conductors used to carry only data bits. Or, some conductors may be used to transmit some combination of address, control, and/or data bits at different times or through a packetized or arrangement.
FIG. 2 illustrates a system 20 including integrated circuits IC0, IC1, IC2 . . . ICn. The integrated circuits are connected through busses 24-1, 24-2, . . . 24-n. IC0 may be a controller to control the other integrated circuits or can be the same as them. System 20 is of the type that is sometimes referred to as point-to-point bus system. An optional conductor 28 completes the loop. System 10, by contrast, is referred to as a radial bus system.
A disadvantage of radial bus systems is that they are slower do to the relatively large amount of capacitance associated with relatively long conductors and multiple receiving circuitry in IC0, IC1, IC2, . . . ICn. An associated disadvantage is that energy is dispersed through the stubs as well as through the bus. For example, in FIG. 1, at the junction of the bus 16 and stub 18-1, some electrical energy passes through stub 18-1 and other electrical continues through bus 18 past stub 18-1. This reduces the effective bus speed.
Another disadvantage of current point-to-point systems is that in many systems there is a set number of chips. Even if the number of chips can be added to by adding to the last chip, if a chip in the interior of the loop fails, the whole system is down. For example, in FIG. 2, if IC2 is defective, the entire system may be nonoperational. By contrast, multi-drop systems are typically relatively easy to add to and in many such systems, if one of the chips fails, the system as a whole can still operate. For example, in FIG. 1, if IC2 is defective, the rest of the system may be able to continue.
Bi-directional signaling refers to using the same conductors to transmit signals in both directions. For example, data may be transmitted either to or from an integrated circuit. If the same conductor is used in both directions, the signaling is bi-directional. The bi-directional signaling may be sequential or simultaneous. In the case of sequential bi-directional signaling, enable signals may be used to, for example, tri-state or turnoff unused drivers or receivers. In the case of simultaneous bi-directional signaling, the threshold voltage of the receiver may be changed depending on the state of the adjacent driver. For example, if the adjacent driver is transmitting a 0, the receiver threshold may be set to Vcc/4. If the remote driver is also 0, the threshold will not be met. If the remote driver is a 1, the Vcc/4 threshold will be met. If the adjacent driver is also transmitting a 1, the receiver threshold may be set to 3Vcc/4. If the remote driver transmits a 1, the threshold will be met and if it transmits a 0, the threshold will not be met.

Integrated circuit stubs in a point-to-point system


Systems and methods for conducting contact-free thickness and refractive-index measurements of transparent objects, such as intraocular lenses using a dual confocal microscopy system are disclosed.

The development and use of intraocular lenses ("IOL") for refractive cataract surgery has changed the life of cataract patients and has become more popular since the first implantation of such lenses in 1949. Among many of the physical parameters that determine the characteristics and quality of an intraocular lens, focal length (or dioptric power), modular-transfer function ("MTF"), astigmatism, thickness, and refractive index play important roles. MTF, astigmatism, and dioptric power can be measured using commercially available IOL-characterization equipment. However, in spite of their significance in the characterization of intraocular lenses, thickness and refractive index of an intraocular lens have not been precisely measured by users. It has been found that the thickness of an intraocular lens cannot be accurately measured by simple mechanical devices, such as calipers or micrometers, since these mechanical devices can affect the optical quality of the intraocular lens since such a method requires that the intraocular lens be brought into direct physical contact by these mechanical devices during measurement. In addition, the curvature of the intraocular lens itself can raise difficulties for obtaining precise thickness measurements. As such, there is a need for determining the precise thickness and refractive index of an intraocular lens that does not require direct contact with the intraocular lens.

Systems and methods for conducting contact-free thickness and refractive-index measurements of intraocular lenses using a self-calibrating dual confocal microscopy system

The United States of America as represented by the Secretary, Department of Health and Human Services


In a system which includes adaptors a controller and plug receptacles connected to electronic devices, an adaptor that can store identification information about electronic devices is connected to an electronic device, and the plug receptacle side to which the electronic device is connected transmits to the power line its own identification information, etc. in coordination with the identification information of electronic devices from the adaptor. The controller receives this information and keeps track of locations of the electronic devices.

1. Field of the Invention
This invention relates to a system that keeps track of the location of various electronic devices using AC lines (power lines), and various devices used in the system, including adaptors, controllers, and plug receptacles.
2. Description of the Prior Art
The idea of communicating using AC lines (power lines) is already known (see unexamined patent H10-341249 [1998]). The idea is also already known to provided within amusement devices a trouble information collection device that collects error information and other trouble information, a coin information collection device that collects information about sales, and a power line modem that superimposes on the power lines within the facility, as data, the collected trouble information, sales information, and other information within the device, and to have a central controller that collects data from power lines within the facility via a power line modem and controls the amusement devices (see unexamined patent H6-210067 [1994]).
However, in controlling electronic devices of many different types, there is the problem that their arrangement position and storage position cannot be managed efficiently.
That is, although internal information for each amusement device can be reported to a collection device by connecting amusement devices to the power line, one cannot obtain such information as where an amusement device is located.

Adaptor; controller and plug receptacle for electronic device


An apparatus for dispensing a hydratable material includes a source of the hydratable material to be dispensed, including a container and a metering unit. A continuous-flow first mixer has a truncated conical mixing chamber with an open upper end and an open lower end of smaller diameter than the upper end. The upper end is disposed to receive the flow from the metering unit and the lower end delivers a flow of a mixture of the hydratable material and water. A plurality of water inlet openings at an upper end of an inner surface of the conical mixing chamber introduce water tangentially along the inner circumference of the cone to create a vortex effect within the cone. A continuous-flow second mixer is positioned directly adjacent to and below the first mixer and receives the flow of mixture from the first mixer. The second mixer includes at least one outlet opening of a size less than a preselected size, an impeller disposed to mix the mixture of hydratable material and water with high energy and force the mixture toward the outlet opening, and a motor that turns the impeller to have a tip speed of at least about 25 feet per second.

This invention relates to the dispensing of a relatively small flow of a solid or liquid into a mass of fluid, and, more particularly, to the dispensing of an even, unagglomerated flow of a hydratable material.
In some mineral beneficiation processes, a flocculant is dispensed into a fluid to clarify the fluid of solids (including colloids) that are present in the fluid. The flocculant is a hydratable material that first is wetted by the fluid as it is mixed with the fluid, which is typically water or an aqueous solution. Ideally, the wetted flocculant thereafter chemically reacts with finely divided solids in the fluid to cause them to agglomerate into larger masses. The masses of flocculated solids are removed from the fluid by filtration or other suitable process.
The dispensing of the flocculant into the fluid sometimes presents some problems. In a typical case, the flocculant is a finely divided powder. The flocculant begins to absorb water and become wetted as soon as it contacts the fluid. However, at the same time its molecular structure changes In a manner comparable to polymerization so that it reacts with solids in the fluid to achieve the flocculation reaction. Since the wetting and chemical reactions are occurring generally simultaneously, the flocculant can sometimes itself agglomerate into masses, often termed "fisheyes" in the art, before it has a chance to react with the solids in the fluid. Any such self-agglomerated flocculant is not available to flocculate solids in the fluid, with the result that the flocculation treatment is only partially effective or is wasteful of the expensive flocculant material.
Existing techniques for dispensing flocculant seek to add the flocculant in a flow and rely upon achieving a degree of mixing of the flocculant with the fluid before the flocculant can self-agglomerate. However, it is found that this approach is often not successful, and flocculant lumps are observed in the fluid regardless of the care taken in adding the flocculant. There is therefore a need for an improved approach to dispensing such hydratable materials into fluid masses. The present invention fulfills this need, and further provides related advantages.

Apparatus for dispensing hydratable material


A device for examining the optical properties of surfaces includes a first radiation source which emits radiation to an examination surface, at least one first detector device, for detecting the radiation reflected off the surface and emitting at least one signal that is characteristic of at least one parameter of the detected radiation, wherein the detector device includes a plurality of image capturing components arranged in a specified detection area and wherein a control is provided for compensating signal changes caused by a shift of the location where the reflected radiation is incident on the detection area.

Devices for examining the optical properties of surfaces are known from the prior art. Generally, these devices use a light source which directs light at the examination surface and a detector that detects and evaluates the light reflected or diffused off of the surface. Such evaluation allows a determination of the optical properties of surfaces such as color, gloss, orange peel and the like. Such a determination or characterization is required since motor-vehicle bodies or their paintwork make different impressions on the human eye depending on the incident light, thus requiring a neutral characterization for comparing different surfaces.
The devices known from the prior art are placed on the examination surface. In the prior art there is the problem that for example in the case of curved surfaces, measurement results of identical measuring points also depend on the incident angle of the light on the examination surface. Such curvatures may also lead to incorrect results.
This effect may occur for example when examining paint coatings comprising pigments or so-called flakes. These pigments or flakes are for instance metal particles statistically distributed in the layer of paint or on its surface. The pigments exhibit different characteristics in dependence on the incident angle of the light such as a slightly changed angle of observation, a different color or a different brightness. If present, the reflected light is particularly strongly affected by deviations from the angle of reflection.

Apparatus for the examination of the properties of optical surfaces