The subject invention relates to a toughened epoxy matrix formulation useful as a prepreg for fiber reinforcements comprising at least two epoxy components, an amine hardener and about 10%-25% of a micropulverized polyimide thermoplastic having a molecular weight of from about 20,000 to about 100,000 and Tg of at least about 220.degree. C. The invention further relates to a process for preparing a toughened epoxy matrix formulation comprising:. a. preheating a blend of at least two epoxy compounds to a temperature of about 130.degree. F. to about 140.degree. F.; PA1 b. blending into the epoxy blend from step (a) a micropulverized polyimide thermoplastic; PA1 c. mixing the blend of epoxy and thermoplastic at a temperature of about 110.degree. F. to about 130.degree. F.; and PA1 d. adding to the blend of epoxy and thermoplastic an amine hardener and mixing at about 110.degree. F. to about 130.degree. F. until a low mix viscosity is obtained.

Epoxy resins, due to their good processability combined with good mechanical properties and good high temperature performance, are materials commonly used for the production of high performance composite structures. Such resins usually consist of blends of various epoxies, curatives and additives, which enhance specific characteristics of the epoxy or impart new characteristics to the epoxy. These high performance epoxy matrices, reinforced with fiber, are used widely in the advanced composite industry.
Advanced composites are cured articles resulting from the combination of epoxy or other high performance matrices with a reinforcing fiber, such as glass fiber, aramid fiber (organic fiber), or graphite fiber or fabric, to form prepreg material. In order for prepregs to be useful for manufacturing primary structures, they must possess certain physical and mechanical characteristics. One such characteristic is defined by compression after impact testing, and relates to the retention of compressive strength upon sustained damage to the material. Other desirable characteristics include hot/wet performance, which relates to the performance of the material at high temperatures under humid conditions, working life, and tack and drape, which relate to processability and handleability. Therefore, these materials are evaluated by not only their mechanical performance, but also their handleability and/or processability.
Cured epoxy resins, due to high cross-linking density, display good temperature performance. Unfortunately, however, cured epoxy resin parts lack the needed toughness and are brittle. One solution used to compensate for this brittleness has been to incorporate rubber into the epoxy resin formulation. Rubber tends to improve the toughness of the epoxy by preventing the propagation of cracks and bolstering the strain capability. Other elastomers, such as nylon or liquid reactive oligomers of butadiene acrylonitrile rubbers, have also been used to enhance the toughness in epoxy resin systems.
The use of rubber or other similar elastomeric additives, however, has a significant drawback in that these additives generally possess low modulus and therefore reduce the stiffness of the cured article. The resulting composite material, therefore, displays a commensurate reduction in strength. Also, rubbers and elastomers tend to have low glass transition temperatures, which contributes to the diminished hot/wet performance of composites containing these additives. U.S. Pat. No. 4,680,076 discloses multiphase epoxy thermosets having a crosslinked continuous phase and a crosslinked discontinuous phase which contains a rubber phase.
Reactive oligomers have also been used to enhance the toughness of epoxy resin systems. The resulting systems are characterized by a phase inverted morphology. The most popular thermoplastic oligomer used to toughen epoxy resins has been an amine-terminated polysulfone. Use of this oligomer, however, presents problems in terms of reproducibility, as well as hot/wet performance and out-time. U.S. Pat. No.'s 4,656,208 and 4,656,207 disclose thermoset compositions having multiphase morphology with at least one glassy continuous phase and at least one glassy discontinuous phase, and comprising a polyepoxide component, an amine hardener, and a specified amount of an aromatic oligomer with functional groups which react with the polyepoxide and/or hardener when cured.
More recently, the industry has attempted to solve the toughness problem of epoxy composites by incorporating linear polysulfone thermoplastics into the epoxy formulation. Such polysulfone thermoplastics are specifically tailored to exhibit a spinodal morphology in the cured epoxy matrix. While these thermoplastics do help solve the tughness problem encountered with cured epoxy resins, they only marginally improve the hot/wet performance of the resin as compared to the results achievable when using rubber or elastomers as the additive.
Polyimide thermoplastics have also been used in conjunction with epoxy resins. U.S. Pat. No. 4,567,216 discloses an epoxy composition modified with a thermoplastic to improve tensile properties. The composition contains a bis(2,3-epoxyclyclopentyl)ether, a diamine hardener and a phenoxy, polycaprolactone, polyetherimide or polyarylether thermoplastic. The polyimide thermoplastic is usually combined with the epoxy in a solution blend, requiring that the amount of thermoplastic added be less than 10%. Amounts in excess of 10% polyimide thermoplastic dissolved in the epoxy formulation can not be handled due to the excessive viscosity of the material. The solution of thermoplastic in the epoxy is normally accomplished by either dissolving the two components in a common solvent and removing the solvent while mixing the material, or by heating the thermoplastic and the epoxy to a temperature above the Tg of the thermoplastic and melting the two components together. The high viscosity, as well as poor tack, drape and stiffness, make the matrix unacceptable for hot melt processing or for prepregging. Using less than 10% thermoplastic solution allows the user to control the viscosity of the matrix, however, the resultant composite will not achieve the desired toughness.
It has been found that the rate of increase in viscosity of the epoxy-polyimide thermoplastic blend is much higher than the rate of increase in toughness of the resultant matrix. In other words, the limiting factor for toughening the epoxy with the polyimide thermoplastic has been the exponential viscosity increase, making these materials unsuitable for prepregging purposes.
Therefore, while a greater percentage of polyimide thermoplastic in the resin positively increases the toughness of the resin, anything over about 10-12% polyimide increases the viscosity of the resin to a point where the resin is no longer processable. For prepreg processing purposes, the tolerable limit of addition of polyimide thermoplastic to epoxy resin is in the 8-10% range. Consequently, optimum toughness must be sacrificed in order to maintain processability of the resin.
Therefore, it is an object of the subject invention to provide a novel epoxy resin formulation for use in the advanced composite industry which displays increased toughness, and good processability and handleability, while maintaining good thermal characteristics.
It is another object of this invention to provide a process for producing a toughened epoxy matrix which displays good handleability as well as excellent performance characteristics.

Epoxy matrix containing amine hardener and micropulverized polyimide


A product display system which includes a basic unit including a track, a front wall, a back wall and a side member. The basic unit is easily assembled and disassembled. Two of more basic units can be ganged together to created customized displays to accommodate a wide varies of products of various sizes.

Product displays for use in retail establishments typically are designed to display products so that the products are easily visible and accessible to the consumer. A drawback to conventional product displays is that they do not provide easy access to the products. Another drawback in conventional displays is that either the displays cannot or do not easily accommodate different sized products. A retailer therefore has to purchase several different displays to display various sized products.


A portable light and reflector for use on the spoke of a bicycle wheel or on other similar vehicles uses a centrifugal switch to complete an electrical circuit between a light source and power source. The centrifugal switch responds to the centrifugal force occurring from the rotation of the wheel. The centrifugal switch, power source and lighting circuitry is mounted within a water tight chamber of the light and reflector housing. The housing contains both translucent and reflective surfaces to take advantage to light incident upon the reflector from outside sources as well as transmitting light and reflecting light from the light source provided. The portable light and reflector disclosed use an LED and lithium battery and is has an easy method for assembling and attaching the housing to the spoke of the bicycle wheel.

Lights, warning lights and reflectors for use on bicycles and other vehicles are well known and have been widely used for years in promoting safe driving habits during dark or dimly lit driving conditions. Reflectors of varying colors have been placed on bicycles to reflect the lights from approaching vehicles. The reflectors have been mounted on the fenders, seats, pedals, handle bars and on as many surfaces as possible so that approaching vehicles can see that the bicycle is present and in the interest of safety, avoid an unwanted accident. Reflectors placed on the spokes of bicycle wheels are effective in not only the light that is reflected but in the circular motion that is distinctive of a traveling bicycle. Lights as well as reflectors have been adapted to the rotating wheel for the same reason. Emitting light in the distinctive rotational manner is an excellent indicator to approaching vehicles that a bicycle is present. Should the approaching vehicle or conditions fail to provide sufficient light to reflect off of the bicycle or any reflector on the bicycle, light emanating directly from the bicycle will eliminate that need.
Reflectors typically use mirrored surfaces or multifaceted lenses to reflect incident light. Lights typically use mirrored surfaces and direct the beam of light outward toward the direction preferred depending on the placement of the light on the bicycle and the optimum direction sought for giving notice to any oncoming vehicles. Power for the light source has been provided by mounting a battery within the light housing and by the use of hub mounted generators and wire leads connected to from the generator to the light source. Combinations of a light and reflector have been incorporated into a spoke mounted assembly. Switches have been added to the lighting circuits that require a positive manual action to switch the light on and off when needed. Centrifugal switches have also been incorporated into circuitry that uses the centrifugal force of the rotation wheel. The inherent objective or goal is to provide a warning and visual indication to oncoming vehicles that a bicycle is near and that safety be a prime consideration.
U.S. Pat. No. 4,135,229 (Safety Device for Use on a Bicycle Wheel) issued to Modurkay on Jan. 16, 1979 discloses a combination of reflector and light for mounting on the spokes of a bicycle wheel includes the use of a battery clamped to the wheel hub. A socket receiving an electric light bulb is mounted within a housing having transmissive side walls and means for clamping the housing to spokes of the wheel with the light transmissive side walls facing laterally away from the wheel. The means for electrically connecting the light bulb socket in series with the battery includes a switch that enables one to turn off the light when it is not needed, thereby conserving the battery.
U.S. Pat. No. 4,796,972 (Illuminated Spoke Mounted Reflector for Bicycles) issued to Thomas et al. on Jan. 10, 1989 discloses a rotary electrical contact assembly that is mounted on the axle of a bicycle wheel. The rotary electrical contact assembly provides power from a conventional bicycle generator to light bulbs within reflectors mounted on the spokes of the bicycle wheel. A slidable switch on the rotary electrical contact assembly is connected to a shift cable for remote manual actuation by the bicycle rider. A constant or flashing mode operation can be selected.
U.S Pat. No. 4,787,014 (Spoke Mounted Bicycle Light) issued to Wodder et al. on Nov. 22, 1988 discloses a safety lighting device containing a self contained light source that is removably secured to the spoke of a wheel. The patent points out the excessive amount of night time fatalities that result from collisions between automobiles and young riders under the age of 14. Also pointed out is the fact that reflectors alone have limited distances in which they can be effective and typically lights provide only thin beams. It goes on to state how the use of generators are often unreliable, relatively expensive, and undesirable for use by these younger riders due to the drag that is placed on the wheel. In essence, the patent expresses the need for a low cost bicycle safety light which renders the cyclist highly visible to motorists, which is easy to install and maintain, and which will be accepted for long term use by younger riders.
U.S. Pat. No. 4,176,390 (Light) issued to Galbert on Nov. 27, 1979 discloses a light that is mounted to the spoke of a bicycle wheel. The light turns off automatically when the bicycle is not being ridden, and turns on automatically in response to centrifugal force when the bicycle is being ridden. A light bulb is affixed to the wheel in a manner that orients the light's battery on an axis positioned radially or the wheel and that orients the light's battery radially inward of the light's bulb. A switch spring is provided that normally biases the battery out of electrical contact with the bulb when the wheel is not rotating, but which permits the battery to be biased into electrical contact with the bulb in response to centrifugal force when the wheel is rotating and thus turn on the light.
U.S. Pat. No. 5,016,144 (Illuminating Wheel Covers) issued to DiMaggio on May 14, 1991 discloses a rotating mercury switch which gathers mercury during rotation and causes a momentary electrical contact. Light emitting diodes (LED) are arranged in an array and activated by the mercury switch. A 9 volt battery is used as the power source for what is described as a unique and improved illumination wheel cover using advanced electronics to illuminate light emitting diodes, aesthetically arranged to create an illusionary effect.

Bicycle wheel portable light and reflector


An energy subtraction processing method and apparatus for radiation images includes irradiating radiation, which has a predetermined energy range, into an object in a recording unit, and irradiating the radiation, which has passed through the object, to a recording medium capable of recording a plurality of radiation images during its exposure to radiation with different energy distributions. A plurality of radiation images of the object are thereby recorded on the recording medium. From the recording medium on which the radiation images have been recorded, a plurality of image signals are obtained by a read-out unit. The image signals represent the radiation images of the object. A modulation transfer function (MTF) correcting process is carried out on the image signals in an operation unit such that differences between MTF's of the radiation images of the object may be eliminated. Subtracting operations are then carried out in the operation unit on image signals, which are obtained from the MTF correcting process.

1. Field of the Invention
This invention relates to an energy subtraction processing method for radiation images, and an apparatus for carrying out the energy subtraction processing method for radiation images. This invention also relates to a superposition processing method for radiation images, and an apparatus for carrying out the superposition processing method for radiation images. This invention further relates to an apparatus for reading out radiation images from two or more stimulable phosphor sheets and obtaining the image signals, which represent the radiation images and which are to be subjected to one-shot energy subtraction processing or superposition processing.
2. Description of the Prior Art
Techniques for reading out a recorded radiation image in order to obtain an image signal, carrying out appropriate image processing on the image signal, and then reproducing a visible image by use of the processed image signal have heretofore been known in various fields. For example, as disclosed in Japanese Patent Publication No. 61(1986)-5193, an X-ray image is recorded on an X-ray film having a small gamma value chosen according to the type of image processing to be carried out, the X-ray image is read out from the X-ray film and converted into an electric signal, and the electric signal (image signal) is processed and then used for reproducing the X-ray image as a visible image on a copy photograph or the like. In this manner, a visible image having good image quality with high contrast, high sharpness, high graininess, or the like can be reproduced.
Also, when certain kinds of phosphors are exposed to radiation such as X-rays, .alpha.-rays, .beta.-rays, .gamma.-rays, cathode rays or ultraviolet rays, they store part of the energy of the radiation. Then, when the phosphor which has been exposed to the radiation is exposed to stimulating rays such as visible light, light is emitted by the phosphor in proportion to the amount of energy stored thereon during its exposure to the radiation. A phosphor exhibiting such properties is referred to as a stimulable phosphor. As disclosed in U.S. Pat. Nos. 4,258,264, 4,276,473, 4,315,318, 4,387,428, and Japanese Unexamined Patent Publication No. 56(1981)-11395, it has been proposed to use stimulable phosphors in radiation image recording and reproducing systems. Specifically, a sheet provided with a layer of the stimulable phosphor (hereinafter referred to as a stimulable phosphor sheet) is first exposed to radiation which has passed through an object, such as the human body. In this manner, a radiation image of the object is stored on the stimulable phosphor sheet. The stimulable phosphor sheet, on which the radiation image has been stored, is then scanned with stimulating rays, such as a laser beam, which cause it to emit light in proportion to the amount of energy stored during exposure to the radiation. The light emitted by the stimulable phosphor sheet, upon stimulation thereof, is photoelectrically detected and converted into an electric image signal. The image signal is then used during the reproduction of the radiation image of the object as a visible image on a recording material such as photographic film, on a display device such as a cathode ray tube (CRT), or the like.
Radiation image recording and reproducing systems which use stimulable phosphor sheets are advantageous over conventional radiography using silver halide photographic materials, in that images can be recorded even when the energy intensity of the radiation to which the stimulable phosphor sheet is exposed varies over a wide range. More specifically, since the amount of light which the stimulable phosphor sheet emits when being stimulated varies over a wide range and is proportional to the amount of energy stored thereon during its exposure to the radiation, it is possible to obtain an image having a desirable density regardless of the energy intensity of the radiation to which the stimulable phosphor sheet was exposed. In order for the desired image density to be obtained, an appropriate read-out gain is set when the emitted light is being detected and converted into an electric signal (image signal) to be used in the reproduction of a visible image on a recording material, such as photographic film, or on a display device, such as a CRT.
In the radiation image recording and reproducing systems wherein recording media, such as X-ray film or stimulable phosphor sheets are used, subtraction processing techniques for radiation images are often carried out on image signals detected from a plurality of radiation images of an object which have been recorded on the recording media.
With the subtraction processing techniques for radiation images, an image is obtained which corresponds to a difference between a plurality of radiation images of an object recorded under different conditions. Specifically, a plurality of the radiation images recorded under different conditions are read out at predetermined sampling intervals, and a plurality of image signals thus detected are converted into digital image signals which represent the radiation images. The image signal components of the digital image signals which represent the image information recorded at corresponding sampling points in the radiation images are then subtracted from each other. A difference signal is thereby obtained which represents the image of a specific structure or part of the object represented by the radiation images.
Basically, subtraction processing is carried out with either the so-called temporal (time difference) subtraction processing method or the so-called energy subtraction processing method. In the former method, in order for the image of a specific structure (for example, a blood vessel) of an object to be extracted from the image of the whole object, the image signal representing a radiation image obtained without injection of contrast media is subtracted from the image signal representing a radiation image in which the image of the specific structure (for example, a blood vessel) of the object is enhanced by the injection of contrast media. In the latter method, such characteristics are utilized that a specific structure of an object exhibits different levels of radiation absorptivity with respect to radiation with different energy levels. Specifically, an object is exposed several times to radiation with different energy levels, and a plurality of radiation images are thereby obtained in which different images of a specific structure are embedded. Thereafter, the image signals representing the plurality of the radiation images are weighted appropriately and subjected to a subtraction process in order to extract the image of the specific structure. The applicant proposed novel energy subtraction processing methods using stimulable phosphor sheets in, for example, U.S. Pat. Nos. 4,855,598 and 4,896,037.
With the energy subtraction processing method proposed in U.S. Pat. No. 4,896,037, the operation for recording a radiation image is carried out twice with two kinds of radiation different in energy level, the two radiation images thus recorded are read out, and two digital image signals are thereby obtained. A subtraction process is then carried out on the digital image signals. Also, U.S. Pat. No. 4,855,598 discloses an energy subtraction processing method (one-shot energy subtraction processing method) wherein two radiation images to be subjected to the energy subtraction processing are recorded with a single recording operation. With the disclosed method, for example, a filter which exhibits different levels of absorptivity with respect to different radiation energy levels is located between two recording media, and the two recording media are simultaneously exposed to radiation which has passed through an object.
When subtracting operations are carried out on the image signals, which represent a plurality of radiation images, with one of the energy subtraction processing methods described above, high-frequency components of the original radiation images remain in a difference image signal, which is obtained from the subtraction processing. The high-frequency components constitute an artifact in a visible image (subtraction image), which is reproduced from the difference image signal. As a result, the image quality of the subtraction image becomes bad.
Also, with the energy subtraction processing method proposed in U.S. Pat. No. 4,896,037, because a certain length of time occurs between the two operations for recording the radiation images, there is the risk that the object moves during the time interval. As a result, the two radiation images thus recorded do not coincide with each other, and a motion artifact occurs in the visible image reproduced from a difference image signal, which is obtained from the subtraction processing carried out on the image signals representing the two radiation images. Thus a visible image having good image quality cannot be obtained.
With the energy subtraction processing method proposed in U.S. Pat. No. 4,855,598, no motion artifact due to movement of the object occurs in the visible image (subtraction image) reproduced from a difference image signal, which is obtained from the subtraction processing carried out on the image signals representing the two radiation images. However, the proposed method has the problems in that, even when the image quality is identical for a center part and peripheral parts in each of the radiation images, which are subjected to the subtraction processing, the image quality of peripheral parts of a subtraction image obtained from the subtraction processing becomes worse than the image quality of the center part of the subtraction image.
Additionally, in the radiation image recording and reproducing systems wherein recording media, such as X-ray film or stimulable phosphor sheets are used, superposition processing techniques for radiation images are often carried out on image signals detected from a plurality of radiation images of an object which have been recorded on the recording media.
With the superposition processing techniques for radiation images, an image is obtained which corresponds to a sum (mean value) of image signals representing a plurality of radiation images of an object. The superposition processing techniques are carried out in order to eliminate or reduce noise components, such as quantum noise components of radiation used during the recording of a radiation image of an object Specifically, as disclosed in, for example, U.S. Pat. No. 4,356,398, a plurality of the radiation images are read out at predetermined sampling intervals, and a plurality of image signals thus detected are converted into digital image signals which represent the radiation images. The image signal components of the digital image signals which represent the image information recorded at corresponding sampling points in the radiation images are then weighted appropriately and added together.
However, the conventional superposition processing techniques have the problems in that, even when the radiation images subjected to the superposition processing were recorded simultaneously, and even when the image quality is identical for a center part and peripheral parts in each of the radiation images, which are subjected to the subtraction processing, the image quality of peripheral parts of a superposition image, which is obtained from the superposition processing, becomes worse than the image quality of the center part of the superposition image.

Energy subtraction processing method and apparatus, superposition processing method and apparatus, and radiation image read-out apparatus


The present invention provides a method for handling reordered data packets. A method comprises receiving a data packet and determining if the data packet is received out of order. The method further comprises delaying transmission of an acknowledgement indicating that a data packet is missing in response to determining that the data packet is received out of order.

1. Field of the Invention
The invention generally relates to network communications, and, in particular, to handling data packets that are reordered in a network.
2. Description of the Related Art
The design of error and congestion control mechanisms in Transmission Control Protocol (TCP) is generally based on the premise that packet loss is an indication of network congestion. Upon detecting loss of data packet(s), a TCP sender backs off its transmission rate by decreasing its congestion window. TCP uses two strategies for detecting packet loss. The first one is based on the sender's retransmission time-out (RTO) expiring and is sometimes referred to as "coarse time-out." When the sender times out, congestion control responds by causing the sender to enter slow-start, thereby drastically decreasing its congestion window to one segment. The other loss detection mechanism originates at the receiver and uses TCP's sequence number. Essentially, the receiver observes the sequence numbers of packets it receives, and a "hole" in the sequence is considered indicative of a packet loss. The receiver generates a "duplicate acknowledgment" (or DUPACK) for every "out-of-order" packet it receives. Until the missing packet is received, each received data packet with a higher sequence number is considered to be "out-of-order," and will cause a DUPACK to be generated. The transmission of DUPACK(s) is described in Request for Comments (RFC) 2581, entitled "TCP Congestion Control," dated April, 1999.
Packet reordering is generally attributed to transient conditions, pathological behavior, and erroneous implementations. For example, oscillations or "route flaps" among routes with different round-trip times (RTTs) are a common cause of out-of-order packets. Another cause of packet reordering can be network routers that provide parallel paths for data packets associated with a same connection. That is, for performance reasons, network routers may transmit incoming data packets over parallel (or alternative) paths to a destination, even though the data packets are associated with the same connection. Thus, the data packets can arrive at their intended destination out of order. One example of a router that can cause packet reordering is Etherchannel® provided by Cisco®.
To improve network performance in the event packet reordering occurs, some TCP implementations have adopted a "fast retransmit" algorithm that infers that a packet has been lost after the sender receives a few DUPACKs. The sender then retransmits the lost packet without waiting for a time-out and reduces its congestion window in half. The "fast retransmit" algorithm is generally intended to improve TCP's throughput by avoiding the sender to time-out (which results in slow-start and consequently the shutting down of the congestion window to one).
Fast retransmit can improve TCP's performance in the presence of sporadic reordering. However, it still operates under the assumption that out-of-order packets indicate packet loss, and therefore congestion, even though no actual loss may have occurred. Consequently, the network performance degrades considerably in the presence of persistent reordering because the repeated false fast retransmits can keep the sender's congestion window relatively small.
The present invention is directed to addressing, or at least reducing, the effects of, one or more of the problems set forth above.

Method for handling reordered data packets

International Business Machines Corporation


A structural brace apparatus and method provides support between a primary building component and a secondary building component, the primary building component having X and Y axis deflections relative to the secondary building component. The brace includes a first support arm having a longitudinal axis, the first arm extending from and adapted to be secured to the primary building component, the first arm longitudinal axis being positioned at an intermediate angle between the primary building component X and Y axis deflections. The brace also includes a second support arm extending from and adapted to be secured to the secondary building component, the second arm has a slidable engagement with the first arm for reciprocative movement substantially parallel to the first arm longitudinal axis, wherein the brace is operative to reduce transmission of the X and Y axis deflections from the primary building component to the secondary building component.

Building structures have numerous deflections, due to the various sizes, materials of construction, and different loadings that a building structure can experience. In particular, multistory structures can experience the different loadings from floor to floor, which results in relatively different deflections between the different floor structures. As there is usually a need for vertical wall structures that are typically non load bearing between the floors, the wall structures must of necessity be structurally attached to the floor and ceiling of a particular level within the building structure. As the aforementioned wall structure is attached to the floor and ceiling which have correspondingly different deflections, these different deflections can transmit into the wall structure causing a wall structure to deflect, crack, or buckle. Thus, there is a need for a way of securing the wall structure to the floor and ceiling, however, requiring at least some degree of flexibility in the securing of the wall structure to allow for the building structure to deflect at relatively different rates from the floor to the ceiling. As is well known in the art, building structural deflection rarely occurs in a singular axis or direction, as most building structures are constructed of lateral beams that are supported by a pair of a freely pivoting attachments which allows the beam to bend from its loading without transmitting the beam bending moment into the other parts of the building structure, meaning that the beam bends in a parabolic profile, which of necessity causes varying degrees of structural deflection at varying points along the beam length. This also results in beam deflections not only vertically but laterally also. Thus, it is very important that a structural brace be designed to accommodate deflection in more than one axis while still providing some measure of support between the two building components.
Accommodating building structural deflections in the support of vertical walls has long been recognized in the prior art, however, the prior art has focused almost exclusively upon vertical only deflections between building structure components that act to support a vertical wall, while providing some degree of lateral or horizontal stability in conjunction with vertical flexibility. One example would be U.S. Pat. No. 5,685,121 to De Francesco et al. that discloses a metal wall stud extension ceiling connector that slides to compensate for ceiling deflection in the event of earthquakes, or other deflections. The extension is positioned vertically and the sliding feature of the metal wall said is designed to accommodate only vertical ceiling deflection. In this same vein, U.S. Pat. No. 6,119,430 to Nicholls also discloses a slidably engaged metal stud wherein the slidable portion is more central to the stud length, which allows a higher degree of vertical deflection to occur in the stud. A further example is in U.S. Pat. No. 5,906,080 to di-Girolamo et al. that discloses a shouldered sliding bracket that typically attaches to the end of a wall stud, wherein the slidable bracket is attached to a ceiling structure, again only designed to accommodate purely vertical deflection of the ceiling structure. A further prior art example is in U.S. Pat. No. 5,313,752 to Hatzinikolas the discloses a wall framing system wherein slidably engaged attachments are affixed to the end of vertical wall studs to allow a limited degree of vertical flexure in the wall, thus accommodating vertical only structural wall flexing between the floor and ceiling of a building structure. Another example is in U.S. Pat. No. 5,040,345 to Gilmour that discloses an end mounted stud clip for allowing vertical floating movement between a floor and a roof structure utilizing a slidable engagement between a C shaped or channel type metal stud in which the stud clip is slidably engaged into. A final example is in U.S. Pat. No. 5,237,786 to Kochansky that discloses an interior wall system that utilizes in one embodiment a plate cylinder within a cylinder having a guide rod that is spring loaded to allow again, only vertical deflection between the floor and ceiling.
What is needed is a structural brace apparatus that can accommodate not only vertical deflections between building components but in addition horizontal or lateral deflections between building components, that result in a combined axes composite deflection between the building components that acts at an angle intermediate to the building component X axis deflection and the building component Y axis deflection. This is required because building structural component deflections are rarely in a singular axis, as the most typical deflection being a beam that deflects in a somewhat parabolic shape resulting in vertical and horizontal deflections, i.e. X axis and Y axis deflections. Thus, a structural brace apparatus is required to accommodate both X axis and Y axis deflections from a building component in an effort to help reduce transmission of these multiple access deflections into another building component to prevent damage to that component, therefore allowing of freedom of movement between the two building components to reduce stress and fracture occurring between the components that are connected by a structural brace apparatus, while the same time providing a measure of some structural support between the building components. Additional desirable features would be the ability of the structural brace apparatus to accommodate a large degree of the flex and at the same time having a retention mechanism to keep the structural brace apparatus from disengaging where it has a slidable engagement.


A system is described in which a plurality of host computers are coupled to a storage system for storing and retrieving data in the storage system. The storage system includes individually addressable units of storage such as volumes or logical unit numbers. A security management system controls access to each of the individually addressable units of storage based upon the identification of the host permitted to access that unit of storage.

This invention relates to storage area networks, and in particular, to security of data in such storage area networks.
Storage area networks (SAN) are now widely deployed around the world to provide storage facilities for computing environments. The consolidation of storage into large facilities allows for more efficient administration and control, and enables the provision of highly reliable backup and redundancy systems to dramatically limit data loss from system failures or natural catastrophes. The benefits of such storage have caused a dramatic increase in its use throughout the world.
Storage area networks are designed to allow access from many different host systems so the data may be reliably retrieved and stored from different locations under the control of different processors. Such storage and retrieval is often carried out over public networks, such as the internet.
To more effectively enable access to the storage system, it is usually configured into smaller portions which can be allocated to different processors or other resources requiring the storage. For example, conventional storage systems include a large number of hard disk drives, with each hard disk drive itself including many gigabytes of storage. One way to divide the storage resource into smaller portions is to create Logical Units that are assigned a unique Logical Unit Number. Each LU itself consists of a numeric address, thereby permitting the large storage system to appear as many smaller storage units to the host computers accessing them, enabling more efficient operation.
The LUs are typically assigned to hosts so that a particular LU may be accessed only by designated hosts which have "permission" to access that portion of the storage system. This provides enhanced security as the software controlling access to the storage system will only permit access by certain previously defined hosts. While it is somewhat arbitrary how many hosts are permitted to access a given LU, conventionally only one host usually has access rights to a given LU at a given time. In this manner the data on the LU is protected against access by hosts or servers other than those previously designated, thereby enhancing the security of the data.
The SAN itself usually consists of one or more disk array devices, for example configured under a selected RAID protocol, with multiple host devices connected by fiber channel switch network devices or other well known means to the storage area network. Inside the architecture, host computers run cluster management software to negotiate with each other to determine which hosts "own" which portions of the storage or LUs. A commonly known "failover" function enables the clustered architecture of the SAN to be highly available. In a failover situation, a failure occurs, but is made relatively transparent to the user of the system by transferring operations that were running on one node to another node or nodes within that cluster of nodes.
The hosts and SAN are configured in a clustered environment in which more than one host has access to a given SAN. The host is typically a computer, for example an application server or a database server. The traditional clustering software used to provide this configuration has a limitation in that a portion of the storage, for example, an LUN, must be configured to allow I/O access from all host nodes in the cluster. For example, if host node A is running an application X, and they are in the same cluster, it is desirable that if host A fails, the task of application X be taken over by another host B. When this happens the LU security for applications must be set to allow I/O access from both hosts A and B. If such multiple access is routinely provided by the set-up program at system initialization, however, it can be a cause of data corruption resulting from the wrong access of the data.
This invention provides an improved method and system for security in such an environment by enabling dynamic changes in the LU security to allow a different host to access a particular portion of the storage after a failure, when that host could not have accessed that portion of the storage before the failure.

Logical unit security for clustered storage area networks


A solid-state imaging device 1 is provided with (1) a photodetecting section 11 in which M×N of pixels are two-dimensionally arranged in M rows and N columns, and a pixel Pm,n at the m-th row and the n-th column includes a photodiode PD1m,n, (2) a row selecting section 20 that selects one or more rows, out of M rows of the photodetecting section 11, instructs each pixel in the selected rows to accumulate an electric charge generated in the photodiode PD1m,n in response to the incidence of light, and instructs to output data corresponding to the amount of accumulated electric charge of each pixel by each row of the photodetecting section 11, and (3) a first signal processing section 30 that inputs data of each pixel, outputted by each row of the photodetecting section 11 by an instruction from the row selecting section 20, and outputs the data by each pixel.

Solid-state imaging devices for imaging a two-dimensional image are provided with a photodetecting section in which M×N pixels, each of which includes a photodiode, are two-dimensionally arranged in M rows and N columns. In each pixel of the photodetecting section, an amount of an electric charge of which corresponds to intensity of an incident light is generated in the photodiode, and accumulated therein. Data corresponding to an amount of accumulated electric charge is outputted. Subsequently, based on the data by each pixel, an image of light incident upon the photodetecting section is obtained. In a CMOS image sensor described in the below-described patent document 1, a substrate bias voltage is changed while the electric charge is being accumulated into the photodiode, and thereby, lowering of a read voltage and enlarging of a dynamic range are implemented.    Patent document 1: Japanese Published Unexamined Patent Application No. 2004-129015

Solid state imaging device including photodetecting section, row selecting section for changing the electric charge accumulating time of each row, and signal processing section


A yoke type paint roller frame having a pair of arms joined at one end and each one terminating at the opposite end on which a roller of selected length can be journalled. A cross bar is connected to respective ones of the pair of arms at a preselected location thereon spaced from the roller and is prevented from sliding longitudinally along respective ones of such arms. At least one end of the cross bar is detachably connected to the frame arm associated therewith by a means for connecting such as a snap fit.

Paint rollers have been used for years to apply a film of liquid paint to a surface leaving a deposited film whose appearance is generally more appealing than if the film had been applied with a brush.
Conventional frames are L-shaped with a handle on the end of one shaft portion and the roller applicator journalled for rotation on the other. The roller may have end caps at opposite ends of the tubular roller and a clip or cap nut is conventionally detachably mounted on the free outer end of the shaft to retain the roller on the shaft. Some form of means is normally provided to keep one end of the roller from abutting against the shaft on which the handle is located.
In another type of roller applicator the end caps are interconnected by a plurality of wires disposed parallel to the shaft and spaced apart from one another circumferentially there around forming a cage that is journalled and retained on the shaft. The roller applicator in this instance is a sleeve that slip fits onto the wire type cage. The distal ends thereof supporting the roller are biased toward one another by the tensile strength of the wire comprising the frame and handle.
In each of the forgoing types of roller applicators the roller pressure will normally be less at the free outer end of the roller that at the end where the shaft and elongate handle are joined. Effectively the shaft with the roller thereon is cantilevered from the elongate handle. This makes them unsuitable for the longer than average roller and dependent upon the tensile strength and/or gauge of the wire frame to bias the distal ends of the frame toward one another supporting the roller there between.
Yoke type of frames are known and by way of example reference may be had to the following United States Patents: Design Patent D334,476 granted Apr. 6, 1993; Design Patent D396.906 granted Aug. 11, 1998; U.S. Pat. No. 581,581 granted Apr. 27, 1897 to M. J. Guthrie; U.S. Pat. No. 2,680,318 granted Jun. 8, 1954 to W. L. Simmons; U.S. Pat. No. 2,811,733 granted Nov. 5, 1957 to M. E. Sloan; U.S. Pat. No. 2,867,832 granted Jan. 13, 1959 to I. Hanninen; U.S. Pat. No. 2,927,334 granted Mar. 8, 1960 to S. Wonso; U.S. Pat. No. 3,310,831 granted Mar. 28, 1967 to W. J. Brinker; U.S. Pat. No. 3,593,361 granted Jul. 20, 1971 to D. I. Welt; U.S. Pat. No. 4,077,082 granted Mar. 7, 1978 to E. O. Roe et al; U.S. Pat. 4,868,946 granted Sep. 26, 1989 to F. Marino et al; U.S. Pat. No. 5,068,951 granted Dec. 3, 1991 to E. M. Abrams; and U.S. Pat. No. 5,509,165 granted Apr. 23, 1996 to I. Zigelbolm.
Yoke type frames allow the user to apply substantially equal pressure at each of opposite ends of the roller. U.S. Pat. No. 3,593,361 and U.S. Pat. No. 4,868,946 teach the yoke arms are adjustably movable toward and away from one another to respectively grasp and release a roller disposed there between. U.S. Pat. No. 2,680,318 and U.S. Pat. No. 2,867,832 teach the free outer ends of the yoke arms are resiliently biased away from one another and are maintained in engagement with the roller by a loop that is slidably disposed on the arms for movement in a direction toward and away from the roller. U.S. Pat. No. 2,811,733 teaches the yoke arms are interconnected by a tension spring that can be made to slide along the arms in a direction toward and away from the roller.
None of the patents teach means for retaining the arm interconnecting means at a preselected location on the yoke arms. U.S. Pat. No. 5,509,165 teaches a rigid yoke frame for rollers that are 2 or 3 feet long rather than the normal 9 or 12 inch roll; however, the yoke arms are interconnected at a selected location but the cross member interconnecting the yoke arms is permanently attached to respective ones of the yoke arms at that location.


Methods and systems for caching graphics data using dedicated level one caches and a shared level two cache are described. Furthermore, each method includes a protocol for maintaining coherency between the level one caches and between the level one caches and the level two cache. The level one caches may store different versions of the graphics data, permitting simultaneous processing of execution threads, each thread accessing a different version of the graphics data.

Current graphics data processing includes systems and methods developed to perform a specific operation on graphics data. Operations such as geometric transformations are applied to a plurality of graphics primitives and constants used during those operations are conventionally stored in a local memory such as a register file or random access memory (RAM).
FIG. 1 is a block diagram of an exemplary embodiment of a prior art Graphics Processing System 100. An Input 105 includes graphics primitives and commands. A Controller 110 receives the commands, including commands to write constants to a Constant Storage 130, e.g., RAM or a register file. Controller 110 outputs graphics primitives and commands to each Processing Unit 120 and processed graphics primitives are output by each Processing Unit 120 to each Output 125. Each Processing Unit 120 reads the constants from Constant Storage 130 while processing the graphics primitives.
Prior to writing a constant to Constant Storage 130, Controller 110 must obtain exclusive write access to Constant Storage 130 to ensure that a constant is not inadvertently modified before being read by either Processing Unit 120. Therefore, Controller 110 determines that each Processing Unit 120 is idle before writing a constant to Constant Storage 130, blocking a unit providing Input 105 if needed until the constant is modified. Blocking Input 105 reduces the throughput of Graphics Processing System 100. Furthermore, when Processing Units 120 are many pipeline stages deep, one Processing Unit 120 may be idle for many clock cycles before the other Processing Unit 120 completes processing and becomes idle.
Accordingly, it would be desirable to provide improved approaches to updating constants accessed by one or more graphics processing units.


A measuring device for measuring gearing and diameters in rotationally symmetrical components (2). The device possesses a fixed feeler pin (9) and a movable feeler pin (10). The movable feeler pin (10), with the aid of a spring actuated mechanism (14), automatically confines the measurable component (2) in a defined measurement position.

Measurement devices of the state of the technology, adaptable for the measurement of gearing and diameters of rotationally symmetrical components, have been established and known for a considerable time. With these so-called universal measurement apparatuses, it is possible to determine inside and outside diameters, sphericities of inside and outside gearing as well as heights. These universal measurement apparatuses are predominately intended for installation in specialized measurement-rooms and are suitable for measuring components with a maximum diameter of some 300 mm. The measurement equipment in use possess a fixed and a movable feeler pin. The component is positioned against the fixed feeler pin and with the aid of the moveable feeler pin, is brought into its final setting, i.e., the measurement position. This can be carried out manually or by spring adjustment.
Measurement devices conforming to the state of the technology are inappropriate for large, heavy components and are considered to be only conditionally usable under shop conditions. Generally the so described measurement devices require special measurement rooms, which are isolated from external conditions. In the case of sizable and heavy components, the movable feeler pin is generally inoperable with regard to bringing the component into a position for measurement. The result of this can be reflected in faulted measurement results. Further, the danger is present that the feeler pin becomes deformed, because of strong mechanical loadings, whereby the measurement equipment finds itself in need of frequent repair. Since the measurement device frequently allows only small movements of the feeler pin equipment, installation and removal of heavy components can also be a source of damage.
The present invention has the purpose of making a measuring device available with which sphericity measurements of inner and outer gearing, as well as inside and outside diameters of cylindrical and conical components, can be precisely determined, which device is sturdily constructed and is adaptable for direct application in the workplace. Especially, the invented measurement device should have the capability of correctly measuring large and heavy components.
The stated purpose of the invention is achieved by a generic measurement device and which the device is applicable to the measurement of gearing and diameters of rotation-symmetrical components.

Measuring device for measuring gearing and diameters in rotationally symmetrical components


Catalyst compositions for the polymerization of an olefin are disclosed which comprise a neutral metallocene and, as the ionizing agent an anionic aluminum-containing complex which is a fluorinated alkoxy and/or aryloxy aluminate. The fluorinated alkoxy aluminate can be of the formula A.sup.+ (Al(OR).sub.4).sup.-, where A.sup.+ is a cation capable of reacting with the neutral metallocene to produce a cationic metallocene and a non-reacting neutral species and R is a fluorinated alkyl and/or aryl group, with a representative group for A.sup.+ being (C.sub.6 H.sub.5).sub.3 C.sup.+ and with the representative fluorinated alkoxy aluminates including Al(OC(Ph)(CF.sub.3).sub.2).sub.4 !.sup.-, where Ph is phenyl, and Al(OC(CH.sub.3)(CF.sub.3).sub.2).sub.4 !.sup.-.

Numerous types of cocatalysts for metallocene-catalyzed olefin polymerizations are known. These include various aluminoxanes, and alkyl and aryl boranes and borates. Such cocatalysts function by forming and stabilizing cationic metallocene and related complexes of the early transition metals, e.g., titanium, zirconium, and hafnium.
These cationic metal complexes are very reactive towards electron donating centers. Anionic complexes with alkoxide ligands can provide sites at the alkoxy oxygen atoms for reaction with the metal cationic species and thereby a mechanism for decomposition of the cation-anion complex.
The synthesis of the Li.sup.+ derivative of the Al(OC(Ph)(CF.sub.3).sub.2).sub.4 !.sup.- complex and its use as a catalyst for 1,4 conjugate additions has been published in Organometallics, 1996, 15, 3776. In these catalytic reactions, it is the Li.sup.+ that is the catalytically active species. The Al(OC(Ph)(CF.sub.3).sub.2).sub.4 !.sup.- anion is a weakly coordinating anion to the Li.sup.+ and imparts hydrocarbon solubility. No other metal species is used.
In a brief survey of the open and patent literature, the present inventors have not come across any specific reference to anionic species with alkoxy ligands, specifically aluminates and borates being used as cocatalysts for olefin polymerization. Generic formulas can encompass the alkoxy aluminates and borates, but all specific examples are for alkyl or aryl aluminates and borates. For example, U.S. Pat. No. 5,407,882 mentions aluminates, but the compounds cited in the description section and in the Examples in this patent document are all aryl and substituted aryl derivatives. In U.S. Pat. Nos. 5,198,401, 5,241,025, 5,408,017, and 5,470,927, generic formulas are given that could be envisioned by hindsight as encompassing the alkoxy aluminates, but specific references to aluminates of any kind are not given. In U.S. Pat. No. 5,241,025, neutral aluminum species of the type AlR.sub.3, where R includes alkoxy groups, are described. The function of these complexes is to act as scavengers for impurities in the polymerization reaction medium, not as activator cocatalysts.

Fluorinated alkoxy and/or aryloxy aluminates as cocatalysts for metallocene-catalyzed olefin polymerizations


Methods and systems associated with a microservice based predictive service level agreement (SLA) impact analytics system that may run on standardized container based virtual computing platform to enable capacity auto-scaling for on-demand, near-real-time resource allocation automatically supporting user data packet forwarding when SLA is potentially impacted to ensure SLA compliance.

Service Level Agreement (SLA) management is critical for carriers to meet customer expectations and experiences. SLA metric measuring methods are well defined in International Telecommunication Union standardization sector (ITU-T) (e.g., ITU-T Y.1540 or ITU-T Y.1541). SLA is violated if at least one SLA performance metric reaches a designated threshold value. In conventional systems, if SLA violation is detected, the operation takes re-active actions to repair customer services with a penalty to service providers as specified in the SLA.

Microservice auto-scaling for achieving service level agreements


An embodiment includes a system comprising: a catheter; an optic fiber having a long axis and a short axis that is orthogonal to the long axis; first and second radiopaque elements coupled to the optic fiber; a first wire coupled to the optic fiber and extending from the first radiopaque element to the second radiopaque element; a fluid; wherein (a)(i) the first wire wraps at least partially around an exterior surface of the optic fiber; (a)(ii) an outer diameter of the first wire and an outer diameter of the optic fiber are collectively less than an inner diameter of the catheter, and (a)(iii) the first wire is configured to center the optic fiber within the catheter within a plane orthogonal to the long axis.

Current endovascular therapies for intracranial saccular aneurysms result in high recurrence rates due to poor tissue healing, coil compaction, and aneurysm growth. Intracranial saccular aneurysms typically develop at the apex of subarachnoid arterial bifurcations at the base of the brain. Subarachnoid hemorrhage, primarily caused by ruptured intracranial aneurysms, affects approximately 1 in 10,000 Americans each year and is fatal in 35% to 50% of all patients.
Standard endovascular treatment using bare metal coils involves delivering several platinum wire coils through a microcatheter into an aneurysm to occlude the aneurysm volume. The treatment goal is for the packed coils to provide sufficient flow stasis to result in embolization of the aneurysm sac and neointima growth across the aneurysm neck. However, implanted bare platinum coils are prone to compaction, result in low volume occlusion ranging from 23-37%, and exhibit a recanalization rate of 21-34% with 13% requiring retreatment. Minimal tissue response to the bioinert platinum coils stunts tissue healing, resulting in unorganized thrombus formation within the aneurysm sac that may not organize within 3 years following treatment. Several devices, including polymer embedded coils, have been investigated in order to improve upon bare platinum coiling outcomes. Bioactive and biodegradable polymer coated coils increase tissue response, but are susceptible to recanalization as the polymer is absorbed. HydroCoils®, coils coated with hydrogel that swells in water, have shown to improve volume occlusion to 45-73%. Although major recurrence has been reported to be lower when using HydroCoils®, the effect on long-term clinical outcomes is unclear.

Heated endovascular catheter injection device


A photosensitive material for electrophotography which comprises a conductive support, and a charge transport layer and a charge generation layer formed on the conductive support, is described. The charge generation layer is formed from a dispersion which is obtained by mixing X-type and/or .tau.-type metal-free phthalocyanine, with or without at least one other charge generation agent, and a resin binder in a solvent, which is capable of dissolving at least a part of X-type and/or .tau.-type metal-free phthalocyanine, to such an extent that a ratio between X-ray diffraction peak intensities at about 7.5.degree. and at about 9.1.degree. is in the range of 1:1 to 0.1:1. When the at least one other charge generation agent is used in combination, the charge generation layer is formed on the conductive support on which the charge transport layer is formed. If such other agent is not used, the charge generation layer is formed on the charge transport layer with a certain thickness. The photosensitive materials have good photosensitivity, image characteristics and printing resistance.

1. Field of the Invention
This invention relates to the art of electrophotography and more particularly, to photosensitive materials which have a double-layer structure of a charge generation layer and a charge transport layer and which are particularly suitable for use in an electrophotographic process including charging, exposing and developing operations to form images.
2. Description of the Prior Art
Organic photoconductive conductors using organic photoconductive materials have a number of advantages over inorganic photoconductive conductors, including the ease in preparation of a variety of materials exhibiting high sensitivity at different wavelengths depending on the molecular design, little or no ecological problem, good productivity and economy, and inexpensiveness. Accordingly, extensive studies have been hitherto made on such organic conductors. Some organic conductors are in use and, at present, are being mainly employed as photosensitive materials for electrophotography.
Known organic photoconductive conductors are usually arranged to have a double-layer structure which includes a charge generation layer capable of absorbing light to generate carriers and a charge transport layer wherein the generated carriers are transported. Many attempts have been made to higher sensitivity. Known organic conductive materials used to form the charge generation agent include various perylene compounds, various phthalocyanine compounds, thiapyrylium compounds, anthanthrone compounds, squalilium compounds, bisazo compounds, trisazo pigments, azulenium compounds and the like.
On the other hand, the materials developed to form the charge transport layer include various hydrazone compounds, oxazole compounds, triphenylmethane compounds, arylamine compounds and the like.
The charge generation and transport agents are, respectively, coated along with polymer binders by relatively simple coating techniques on supports such as drums, belts and the like. Examples of the binders used for this purpose include polyester resins, polycarbonate resins, acrylic resins, acryl-styrene resins and the like. In order to attain high sensitivity by the use of the double-layer structure, it is general that the charge generation layer is applied in a thickness of 0.1 to 1 micrometer and the charge transport layer is applied in a thickness of 10 to 20 micrometers. From the standpoint of the physical strength and the printing resistance, the charge generation layer is formed directly on the substrate and the charge transport layer is formed as a surface layer. In this arrangement, charge transport agents which are now in use are those which act by movement of positive holes. Thus, the known photosensitive materials are eventually of the negative charge type.
The negative charge systems, however, have involved the problem that images are apt to suffer the influence of a support surface. For instance, if an aluminium drum is used, impurities and especially, inorganic metal impurities inevitably contained in the aluminium and irregularities on the surface influence the image quality. More particularly, such impurities or irregularities reflect on image defects such as white and/or black spot defects on images. This becomes more pronounced under high temperature and high humidity conditions. Thus, satisfactory image characteristics cannot be obtained.
Such influences may be mitigated by use of highly pure drum materials, by mirror finish of the drum or by application of an undercoating on the drum, with an increase in production costs. Of these, the undercoating technique is considered to be most suitable. However, a difficulty is involved in an increase of residual potential.
In order to solve the above problems, there is known a positive charge system wherein the charge generation layer and the charge transport layer are superposed in a reverse order as of the case of a negative charge system. However, this positive charge system should be very thin in the charge generation layer as set forth before. This leads to poor mechanical strength and a poor printing resistance. Thus, the known positive charge system has a little utility in practical applications. If a protective layer is formed on the charge generation layer, the printing resistance may be improved but a residual potential will be increased with a lowering of environment resistance.

Photosensitive materials for electrophotography having a double-layer structure of a charge generation layer and a charge transport layer

Matsushita Electric Industrial Co., Ltd.


A vertical heat exchanger is described, which allows efficient elimination of the gas generated therein and efficient removal of the sludge accumulated therein. The vertical heat exchanger has at least part of one end of a vent pipe formed of an upper tube sheet part (an upper cover part in the case of a spiral heat exchanger) and the other end thereof connected outside the heat exchanger to an immediately adjacent fluid passing port passing the same fluid as the vent and/or at least part of one end of a drain pipe formed of a lower tube sheet part (a lower cover part in the case of a spiral heat exchanger) and the other end thereof connected outside the heat exchanger to an immediately adjacent fluid passing port passing the same fluid as the drain.

1. Field of the Invention
This invention relates to a vertical heat exchanger and a method for the use of the heat exchanger.
2. Description of the Related Art
FIG. 1 is a cross section of the general shell-and-tube heat exchanger. Heretofore, it has been customary for a vent pipe 6 to be mounted on the shell, as illustrated in FIG. 1, below an upper tube sheet 8 of a heat exchanger 1 because it is welded as by using a reinforcing ring for the purpose of making up the strength of an opening part thereof and is inevitably required to have a certain distance from the tube sheet. In such a vertical heat exchanger, a high-temperature fluid such as liquid is introduced from a tube side fluid passing port 2 and drawn out from another tube side fluid passing port 3, and conversely a low-temperature fluid such as liquid is introduced from a shell side fluid passing port 4 and drawn out from another shell side passing port 5. In this case, the vent pipe 6 and a drain pipe 7 are not connected to a pipeline. At the time of start, the drain pipe 7 is closed, the vent pipe 6 opened to expel the entrapped gas from the shell, and then during the course of normal operation the drain pipe 7 and vent pipe 6 are both closed.
In this method, however, a gas portion occurs between the vent pipe 6 and the upper tube sheet 8, with the result that a heat-transmission area will be decreased and a thermal efficiency will be lowered in this part of the exchanger. In addition, this gas portion in the gas-liquid phase boundary sometimes induces corrosion of the inner part of the exchanger and the outer part of the tubes.
When the operation of the shell-and-tube heat exchanger is stopped, the drain pipe 7 is utilized to discharge sludge or liquid collected in the shell. This drain pipe 7 is however welded as by using a reinforcing ring adapted for making up the strength of an opening part of the shell and is required to have the allowance of a certain distance from the tube sheet, i.e., the drain pipe 7 is disposed at a level higher than a lower tube sheet 9, so that the sludge accumulated in the part lower than the drain pipe 7 cannot be discharged. In the bottom part of the heat exchanger, sludge is constantly accumulated or part of liquids remains.
Spiral heat exchangers also entail the same problem as the shell-and-tube heat exchangers.


A wavelength conversion sheet filled with a large amount of phosphor, enabling the phosphor to be easily dispersed uniformly and in a large amount near the surface of an LED element. Specifically, the sheet includes: a layer formed from a heat-curable resin composition, which contains 100 parts by mass of a resin component and 100 to 2,000 parts by mass of a particulate phosphor in which the proportion of particles having a sphericity of 0.7 to 1.0 is not less than 60% of all the particles, and which exists in a plastic solid or semisolid state in an uncured state at normal temperature, wherein the average particle diameter of the phosphor is not more than 60% of the thickness of the layer formed from the heat-curable resin composition, and the maximum particle diameter thereof is not more than 90% thereof.

1. Field of the Invention
The present invention relates to a phosphor-containing wavelength conversion sheet, and relates particularly to a wavelength conversion sheet which can convert the wavelength of a blue light or ultraviolet light from an LED by placing the sheet on the chip surface of the LED element and then curing the sheet to cover the element, a method of producing a light emitting device that uses the sheet, and a light emitting device.
2. Description of the Prior Art
In the field of light emitting diodes (LED), the use of phosphors for the purpose of wavelength conversion is already known (Patent Document 1). Because silicone resins exhibit excellent light resistance properties, they are attracting much attention as coating materials for encapsulating and protecting LED elements (Patent Document 2). Further, silicone resin sheets containing low concentrations of phosphors have also been disclosed (Patent Document 3).
Generally, in a white LED, a phosphor is dispersed in the vicinity of the LED chip by using a method in which the chip is coated with a silicone resin or epoxy resin containing a dispersed phosphor, thereby converting the blue light to a pseudo white light. However, if the dispersion of the phosphor within the resin layer lacks uniformity or is biased, then a color shift is likely to occur, and therefore in order to produce a uniform white light, it is necessary to ensure that the phosphor is dispersed uniformly within the coating resin layer. As a result, screen printing methods and methods of uniformly dispersing the phosphor near the lower region of the coating resin layer by precipitating the phosphor have been investigated, but these methods have suffered from problems, including a complex production process and an unsatisfactory level of stability. Accordingly, a technique of easily dispersing a phosphor uniformly in the vicinity of a chip surface has been keenly sought. Wavelength conversion sheets have been implemented as a measure for addressing this issue, but conventional wavelength conversion sheets contain only small amounts of phosphor, and therefore the conversion efficiency has been inadequate.
Further, in LEDs and the like, the resin layer covering the LED element also requires high levels of heat resistance and ultraviolet resistance and the like. It would be very convenient if such resin layers could be formed using conventional production apparatus.
Patent Document 1: JP 2005-524737 A
Patent Document 2: JP 2010-202801 A
Patent Document 3: JP 2009-235368 A

Wavelength conversion sheet filled with large amount of phosphor, method of producing light emitting semiconductor device using the sheet, and light emitting semiconductor device


A transmitter generates a transmitter output signal from first and second baseband signals. The transmitter includes a detector to detect a local oscillator (LO) leakage signal in the transmitter output signal. A controller coupled to the detector determines a direct LO coupling component and a baseband DC offset component of the LO leakage signal. First and second variable current sources are adjusted by the controller to provide first and second DC offsets to the first and second baseband signals, respectively. The first and second DC offsets reduce the direct LO coupling component. Third and fourth variable current sources are subsequently adjusted by the controller to provide third and fourth DC offsets to the first and second baseband signals, respectively. The third and fourth DC offsets reduce the baseband DC component. Overall, reducing the direct LO coupling component and the baseband DC component reduces a power of the LO leakage signal.

1. Field of the Invention
The present invention generally relates to local oscillator (LO) leakage signal reduction. More specifically, the present invention provides independent baseband compensation for a direct LO coupling component and a baseband DC offset component of a LO leakage signal within a transmitter output signal.
2. Background Art
Generally, a wireless radio frequency (RF) transmitter includes a baseband section and an RF section. Baseband information signals are generated and manipulated within the baseband section. The baseband information signals are up-converted and further manipulated within the RF section to produce a transmitter output signal.
Random device mismatches within the constituent components of the baseband section can produce DC offsets within the baseband information signals. These baseband DC offsets can be up-converted by the transmitter to produce a LO leakage signal. Undesired direct coupling of LO signals to the RF section can also produce or enhance a LO leakage signal. The LO leakage signal is an undesirable signal that can interfere with the subsequent detection and demodulation of the transmitter output signal.
The quality of the transmitter output signal suffers if a transmitter fails to compensate for both the direct LO coupling component and the baseband DC offset component of a LO leakage signal. Techniques to reduce a power of the LO leakage signal often estimate and compensate for the direct LO coupling component and the baseband DC offset component simultaneously. Such techniques are expensive in terms of required processing power and required additional components.

Transmitter having reduced local oscillator (LO) leakage by determining direct LO coupling and baseband DC offset


A cantilever probe for scanning a sample surface comprises a cantilever having a free end and a fixed end. A first support section is disposed at the free end and extends along a first plane. A probe is formed on the first support section for scanning movement relative to the sample surface. A second support section is disposed at the fixed end and extends along a second plane different from the first plane. A beam section interconnects the first support member and the second support member to one another and extends along a third plane different from the first and second planes.

The present invention relates to a cantilever probe and a method of manufacturing the same, and more particularly to a cantilever probe and a method of manufacturing the same suitable for a scanning type probe microscope represented by the AFM (Atomic Force Microscope). Further, to describe more specifically, the present invention relates to a cantilever probe and a method of manufacturing the same in which a probe approaching the surface of a sample to be scanned thereby is provided at a free edge of the cantilever and a beam section thereof is deflected by force generated between the probe and the surface of the sample. Also, the present invention relates to observation, when a surface of a sample existing in a liquid is to be observed, of the surface of the sample with an optical lever reflecting section of the cantilever probe kept above the liquid. The present invention also relates to a scanning type probe microscope utilizing the cantilever probe.
A cantilever with a probe provided at a free edge of a beam section thereof supported in a cantilever form has been used as a scanning probe in a scanning type atomic force microscope (AFM). In the cantilever probe having the configuration as described above, when a surface of a sample is scanned with the probe, an attractive force or a repulsive force according to an interatomic force is generated between the sample surface and the probe, so that a form of the sample surface can be measured by detecting the interatomic force as a deflection rate of the cantilever.
A conventional type cantilever probe for an AFM is disclosed in, for instance, Japanese Patent Laid-Open Publication No. HEI 5-196458, in which the cantilever probe 30 has a linear form as a whole as shown in FIG. 5A and both a free edge 30b at which a probe 1 is formed and a fixed edge 30c fixed to a main body of a microscope are present on an extension line of a beam section 30a of the cantilever. However, when the linear cantilever 30 as described above is used for a scanning probe, if the cantilever is arranged in a posture that the beam section 30a is parallel to the surface of a sample, the beam section 30a may contact the surface of the sample if the sample has a largely wavy surface, whereby the probe 1 can not accurately trace the surface of the sample. For this reason, the cantilever probe 30 based on the conventional technology was attached to the main body thereof at an angle, as shown in FIG. 5B, toward the surface of a sample so that the probe 1 can accurately trace the surface thereof without contacting of the beam section 30a with the sample 20 even if the sample has a largely wavy surface.
Also, when a sample in a liquid is to be measured with the conventional type AFM, an entire cantilever probe is required to be sunk in the liquid and a lever section as a reflecting surface of an optical lever is also in the liquid, which makes it difficult to adjust a position of a laser, or a reflecting position is changed due to its refraction, absorption, or change in a liquid surface, so that reflection intensity becomes weaker or accurate measurement can not be carried out.
As described above, when the cantilever probe 30 is attached at an angle toward a surface of a sample, the probe 1 approaches the surface of the sample also at an angle toward it. FIG. 6 is a simulated view showing an interatomic force when the probe 1 approaches the surface thereof at an angle toward it, and it is clear that the interatomic force does not uniformly apply to to the probe 1 in the posture shown in the figure. For this reason, a deflection rate of the cantilever probe 30 cannot accurately represent a distance between the probe 1 and the sample 20, so that the sensitivity is reduced and a measurement error becomes larger. Also, when a sample in a liquid is to be measured, as the entire cantilever probe is sunk in the liquid, a laser for detecting an optical lever is reflected on a liquid surface or absorbed by the liquid, and also reflection intensity of a laser drops or a reflecting position is displaced, which makes it impossible to perform correct or high sensitivity detection.
The present invention was made for solving the problems relating to the conventional technology, and it is an object of the prevent invention to provide a cantilever probe and a method of manufacturing the same in which, even if a probe formed at a free edge vertically approaches a surface of a sample to be scanned thereby, the probe can accurately trace the surface thereof with the main body of the cantilever probe not contacting the surface thereof. Further, it is another object of the present invention to provide a cantilever probe and a method of manufacturing the same in which accurate observation of a sample in a liquid can be performed, when a sample in a liquid is to be observed, because a laser reflecting surface of the cantilever does not sink in the liquid. Another object of the present invention is to provide a scanning type probe microscope utilizing the cantilever probe.

Cantilever probe and scanning type probe microscope utilizing the cantilever probe


The present invention is directed to degradable blends containing polylactide, a degradable impact modifier, and a degradable plasticizer for use in packaging films. The degradable impact modifier can be a degradable, non-toxic elastomer or a degradable, non-toxic, non-elastomeric polymer having a low glass transition temperature, such as polycaprolactone and poly(ethylene glycol). The degradable plasticizer can be any plasticizer having a relatively low molecular weight, a high degree of miscibility with polylactide, and non-toxicity. The film has excellent flexibility and impact strength for packaging applications.

Degradable materials are being investigated for a wide variety of packaging applications to ameliorate the environmental problems associated with conventional, non-degradable packaging plastics, such as polypropylene, polyethylene, poly(vinyl chloride) and polyethylene terephthalate. A promising degradable packaging material is polylactide. When contacted with water, polylactide depolymerizes and decomposes into naturally occurring substances, such as lactic acid, and ultimately can be reduced to water and carbon dioxide. This process is facilitated by heat such as is found in composting.
In typical packaging applications, a desirable degradable packaging material requires a high degree of flexibility and a high impact strength. The amorphous and semi-crystalline forms of polylactide lack these properties. Amorphous and semi-crystalline polylactide have a low impact strength. Both semi-crystalline and amorphous polylactide have a low degree of flexibility.
One method for altering the properties of polylactide to provide greater impact strength is to blend polylactide with non-degradable elastomers or to copolymerize lactide blocks with elastomeric blocks. The elastomeric phase in the composition absorbs the impact energy and thereby improves the impact strength of the polymeric materials. Although such blends are more flexible than semi-crystalline polylactide, they nonetheless have a Young's modulus that is too high for many packaging applications. Additionally, the elastomers commonly employed are not degradable, which is unacceptable for degradable packaging materials. All of the components of a degradable packaging material should be capable of substantially complete degradation.
There is thus a need for a degradable film that has a high degree of flexibility and a high impact strength.
Another need is for a degradable packaging film whose components are each degradable in the environment.
Yet another need is for a degradable polylactide packaging film having a high degree of flexibility and a high impact strength. A related need is for a degradable lawn/ trash bag having a high degree of flexibility and a high impact strength.


Silicone-based nanocomposites that include a plurality of multimodal nanoparticles dispersed within a silicone-based polymeric matrix are provided. Each of the multimodal nanoparticle has a first plurality of long silicone compatible polymeric chains and a second plurality of short silicone compatible polymeric chains grafted onto a surface of a nanoparticle (e.g., an inorganic nanoparticle, such as silica, alumina, titania, indium tin oxide, CdSe, etc.), with the short silicone compatible polymeric chains present on each multimodal nanoparticle at a higher grafting density than the long silicone compatible polymeric chains. Methods are also provided for forming a silicone-based nanocomposite.

Silicone-based polymers are one of the most important polymer classes, due to their wide applications within automotive, health care, and electronic device packaging industries. Silicone based materials have advantages such as high transparency in the UV-visible region, controlled refractive index, stable thermo-mechanical properties, and tunable hardness from soft gels to hard resins. Compared with pure silicone polymer, enhanced mechanical, thermal, electric, dielectric and optical properties can be realized with silicone based nanocomposites by adding functional inorganic nanoparticles. However, the incompatibility between inorganic nanoparticles and an organic matrix normally leads to large agglomerates of the inorganic nanoparticles within the polymer matrix. Such agglomeration leads to a loss in optical transparency and severely limits the use of these materials in optical applications. This result is especially true for silicone nanocomposites because the surface energy difference between inorganic nanoparticles and silicone is very large, creating an even stronger tendency for inorganic fillers to form agglomerates within a silicone-based polymer matrix, when compared to most other organic polymers.
Conventional methods for improving compatibility and dispersion of nanoparticles within such polymer matrices adopted by other researchers include physical sonication and surface ligand engineering. However, these techniques only result in visibly transparent silicone nanocomposites, when relatively thin films are made using a spin-coating method. The high transparency was mainly attributed to its very small thickness and kinetically trapped well dispersed nanoparticles during the fast spin-coating process. Preparation of thick transparent silicone nanocomposites with relatively high nanoparticle loading is very challenging.
Surface ligand engineering of spherical nanoparticles (NPs) to tailor nanoparticle dispersion is one of the grand challenges limiting our ability to harness the potential of nanofilled polymers. The basic principle behind surface ligand engineering is the need to shield the surface of the NP to reduce van der Waals (vdW) core-core attraction, while optimizing the wettability or entanglement of the matrix with the surface ligands. Neither small molecule modification nor monodisperse grafted polymer brushes, in general, achieve stable NP dispersion in bulk polymer matrices. For example, coupling agents such as silanes or surface ligands with carboxylic, amine or other reactive end groups only provide limited success in improving the NP dispersion within a solvent or in monomers, due to inadequate steric hindrance. For monodisperse (mono-modal) grafted polymer brushes, minimizing enthalpic interaction requires high surface coverage or a high value of σ√{square root over (N)} with σ being the brush graft density, and N the number of mers. At matrix molecular weights of interest for commercial use, the entropic penalty is often too high for matrix entanglement, as predicted by the scaling criterion σ√{square root over (N)}>(N/P)2 for a polymer matrix with a degree of polymerization P. Instead, "autophobic dewetting" occurs due to the entropic attraction. In order to reduce the entropic penalty and achieve matrix/brush penetration, either the graft density is decreased at a risk of an insufficient screening effect, or a smaller molecular weight matrix is adopted, which is of little technological importance. This balance between the core/core attraction and entropic repulsion has been modeled by Pryamtisyn et al., and qualitative agreement with experimental data has been shown.
As such, a need exists for improved transparent silicone nanocomposites with relatively high nanoparticle loading.

Silicone based nanocomposites including inorganic nanoparticles and their methods of manufacture and use


A method and apparatus for servicing transmit traffic in a node of a network where the network includes a plurality of nodes connected by first and second rings formed by two or more transmission media. The method includes receiving transit delay data associated with a plurality of downstream nodes, receiving a packet for routing to a destination node in the network and routing the packet to one of the first and second rings not only based on a shortest path to the destination node but also on a transmit latency for both the first and second rings in view of the received transit delay data.

The present invention is directed to network communications.
A communications network such as network 100 of FIG. 1 may include a plurality of stations or nodes (nodes A–F) coupled by transmission media (e.g., cable wire or optical fiber) providing a path for the transmission of data (e.g., E-mail, video, multimedia, or voice) between two or more nodes (e.g. transmission media 140 between nodes A and B, and transmission media 141 between nodes B and C). The data can be transferred in accordance with a network protocol (e.g., Internet Protocol (IP), asynchronous transfer mode (ATM), or synchronous optical network/synchronous digital hierarchy (SONET/SDH)) over optical transmission media. The network 100 may include one or more central nodes and one or more branch nodes connected by an inner ring 126 and an outer ring 146. In this type of network configuration (a dual-ring topology), data can be transmitted from a source node to a destination node (often through intermediary nodes) by transmitting data along one of the two rings (e.g., inner ring 126 and outer ring 146), where the rings have traffic flowing in opposing directions (clockwise direction 110 or counterclockwise direction 111). Control information can be routed in a direction opposite the control information's respective data. As data enters each successive node, local data is split off and transit data passes through the node along the ring. In addition, local data may be added at each node (i.e., transmit data), integrated with the transit data and forwarded on a respective ring to a next node in the network.
In a conventional network using a dual-ring topology, the network can become congested for a variety of reasons. Nodes may oversubscribe and add or forward more data than is expected. Congestion on one ring can in turn cause congestion on the other ring. Congestion management on a conventional network includes the use of logic to monitor and control congestion issues. In a conventional dual ring topology network, when a node is forwarding an excessive amount of transit traffic, the node may communicate its derived usage information to an immediately upstream node via the opposite ring. The upstream node may then adjust its transmission rate (e.g., stop adding data at the upstream node from the upstream node's host to the congested ring). However, in the conventional systems proposed, the usage information provided by a downstream node is limited. The previously proposed systems provide no means for monitoring congestion at other nodes in the network other than a single downstream node.
Data is received in a node (e.g., node B) along a transmission media (e.g., transmission media 140 of outer ring 146 (FIG. 1)). The data received is generally in packet format, where each packet has a header, indicating source and destination information. Data packets are routed using the destination information in the packet header to determine if the packet is destined for the local host (local traffic) or destined for a given ring (transit traffic).
Each node on the ring includes two full duplex ports. One is connected to the inner ring 126 and one is connected to the outer ring 146. A Spatial Reuse Protocol Forwarding (SRPF) block in the node arbitrates between the transit traffic and the host data received (transmit traffic), multiplexing the transit traffic and host data using SRP fairness logic, such as the fairness logic described in "The Cisco SRP MAC Layer Protocol", by Tsiang and Suwala, RFC 2892 (August 2000). The SRP fairness logic is a transmission control logic, which attempts to ensure that nodes get equal usage. The SRP fairness logic determines if a node is sourcing or forwarding an excessive amount of traffic and either imposes rate controls and/or originates and propagates fairness information, requesting that an immediately upstream node adjust its transmission rate. The logic can also be used to prioritize packets and expedite the handling of priority packets.
The SRP fairness logic also includes logic for determining on which ring traffic from a given node is to be added. Typically, ring selection is determined based on a shortest path determination. When packets are received from a host, ring selection algorithms in the SRP fairness logic seek out the shortest path to a destination. By selecting the shortest path, system designers hope to make the best use of system resources. When making decisions regarding adding new packets to a given ring, conventional systems have not previously taken into consideration actual congestion on a given ring. When only path length is considered, added congestion can arise. For example, the traffic load might not be balanced between the two rings. As such, a packet added to a ring that is congested may take longer to traverse the shortest path than if the packet were placed on the other ring (i.e., transit time on the ring with less hop count may be longer than the transit time on the ring with less traffic).
For certain types of packets, other ring selection algorithms are used. For example, with multicast/broadcast traffic, there is no single destination. As such, the shortest path algorithm is not used. For multicast/broadcast traffic, ring selection for each packet can be made using media access control (MAC) addressing techniques. The traffic can be distributed to the rings by hashing the MAC address associated with the traffic. However, the traffic load will be bound to the MAC address distribution.

Dynamic load balancing for dual ring topology networks


A low cost, robust, wireless sensor system that provides an extended period of operability without maintenance is described. The system includes one or more intelligent sensor units and a base unit that can communicate with a large number of sensors. When one or more of the sensors detects an anomalous condition (e.g., smoke, fire, water, etc.) the sensor communicates with the base unit and provides data regarding the anomalous condition. The base unit can contact a supervisor or other responsible person by a plurality of techniques, such as, telephone, pager, cellular telephone, Internet, etc. In one embodiment, one or more wireless repeaters are used between the sensors and the base unit to extend the range of the system and to allow the base unit to communicate with a larger number of sensors. In one embodiment, each sensor is labeled according to its intended location, and system configuration data containing the sensor identification codes and corresponding sensor locations is provided to the user.

1. Field of the Invention
The present invention relates to a wireless sensor system for monitoring potentially dangerous or costly conditions such as, for example, smoke, temperature, water, gas and the like in a building or vehicle, and/or for monitoring energy usage or efficiency of water heaters and the like.
2. Description of the Related Art
Maintaining and protecting a building or complex is difficult and costly. Some conditions, such as fires, gas leaks, etc., are a danger to the occupants and the structure. Other malfunctions, such as water leaks in roofs, plumbing, etc., are not necessarily dangerous for the occupants, but can, nevertheless, cause considerable damage. In many cases, an adverse condition such as water leakage, fire, etc., is not detected in the early stages when the damage and/or danger is relatively small. Sensors can be used to detect such adverse conditions, but sensors present their own set of problems. For example, adding sensors, such as, for example, smoke detectors, water sensors, and the like, in an existing structure can be prohibitively expensive due to the cost of installing wiring between the remote sensors and a centralized monitoring device used to monitor the sensors. Adding wiring to provide power to the sensors further increases the cost. Moreover, with regard to fire sensors, most fire departments will not allow automatic notification of the fire department based on the data from a smoke detector alone. Most fire departments require that a specific temperature rate-of-rise be detected before an automatic fire alarm system can notify the fire department. Unfortunately, detecting fire by temperature rate-of-rise generally means that the fire is not detected until it is too late to prevent major damage.
When a relatively large number of sensor units are used, as in, for example, a commercial building, apartment building, etc., then correlating an identification code in the sensor unit with a location of the sensor unit can become difficult. Correlating the location of a sensor unit with an identification code for the sensor unit can make it difficult to install and maintain the sensor system. Moreover, errors in correlating the location of the sensor unit with an identification code of the sensor unit can lead to potentially life-threatening delays when a sensor reports a dangerous condition and the report sensor cannot be located.