A ventilation device for a fuel tank, including lines situated outside the fuel tank, which include a line intended for operational ventilation and a line intended for refuelling ventilation. These lines are arranged such that the line intended for operational ventilation is located within the line for refuelling ventilation, so that the line for the operational ventilation is prevented from having direct contact with the environment. This keeps the escape of fuel vapors into the environment at a particularly low level.

The invention relates to a ventilation device for a fuel tank of a motor vehicle, having lines guided out of the fuel tank including at least a line for operational ventilation and a line for refuelling ventilation.
Ventilation devices are frequently used in fuel tanks of motor vehicles. They include lines which are each guided to a compensator reservoir provided near the filler neck of the fuel tank. These compensator reservoirs each have a connection to the environment via a common activated carbon filter. Pressure compensation of the fuel tank therefore takes place via the compensator reservoirs and via the lines during refuelling of the motor vehicle and during operation of the internal combustion engine of the motor vehicle.
A disadvantage of the known ventilation devices is that the fuel tank, including the ventilation device, has a very large surface area. A particularly large amount of fuel can pass into the environment via this very large surface area by, for example, diffusion through the walls of the lines. Furthermore, there are a plurality of connecting lines, such as, for example, refuelling ventilation and operational ventilation lines (hereinafter, collectively the xe2x80x9clinesxe2x80x9d), and therefore a plurality of connecting points through which fuel vapor can diffuse. This makes it impossible to obey emission legislation in many locations and/or countries.
The invention is based on the problem of designing a ventilation device so that a particularly small amount of fuel vapor escapes into the environment.
This problem is solved according to the invention by the compensator reservoirs being integrated in the tank, and by the lines having a mutually adjacent wall, at least in a subregion situated outside the fuel tank (the xe2x80x9csubregionxe2x80x9d).
The result of this design is that in the subregion the two lines share an outer wall, and therefore an entire surface area. This reduces the total surface area of the lines and the number of connecting points. This reduction in the surface area of the lines and in the number of connecting points achieves a reduction in the permeation of fuel vapors.
According to an advantageous embodiment of the invention, the escape of fuel vapors can be further reduced if the shared outer wall of the two lines is essentially of cylindrical design. By this means, the two lines have a particularly small, shared surface area.
According to an advantageous embodiment of the invention, the escape of fuel vapors can be further reduced if the lines in the subregion are arranged with one surrounding the other.
According to another advantageous embodiment of the invention, when lines are arranged one surrounding the other, securing the inner line proves to be particularly simple if the inner line is connected to the outer line via at least one web.
According to another advantageous embodiment of the invention, the manufacturing of the lines proves to be particularly cost effective if the inner line is fastened directly to the outer line.
During refuelling, a large volume of air mixed with fuel vapors is generally conveyed out of the fuel tank. According to another advantageous embodiment of the invention, this air is better able to escape if the line for the refuelling ventilation has a larger diameter than the line for the operational ventilation.
According to another advantageous embodiment of the invention, the ventilation device requires a particularly small constructional outlay if the line for the operational ventilation opens into the line for the refuelling ventilation instead of guiding both lines to the activated carbon filter, as is done in prior art devices.
According to another advantageous embodiment of the invention, penetration of fuel from the operational ventilation line into the refuelling ventilation line can be avoided in a simple manner if the opening of the line for the operational ventilation into the line for the refuelling ventilation is arranged at a height which avoids an overflowing of fuel when the motor vehicle is in a sloping position. This arrangement of the lines also has the advantage that the fuel, which travels through the line for the operational ventilation, can return through the line for the refuelling ventilation.
According to another advantageous embodiment of the invention, an incorrect flow of fuel vapors through the lines can be avoided in a simple manner if the line for the operational ventilation can be closed by a valve. A further advantage of this design is that when the line for the operational ventilation is closed by the valve, displacement of the air in the line for the operational ventilation is avoided during the fuel tanking procedure, thus avoiding overfilling the fuel tank during this tanking procedure. The valve can be switched between the open and closed positions electromagnetically or mechanically or can be actuated by the high speed of flow in the operational ventilation or refuelling ventilation lines.
According to an advantageous embodiment of the invention, the escape of fuel vapors can be further reduced if a compensator reservoir, which is arranged in one of the lines, shares a wall with the other line or with another compensator reservoir arranged in the other line.
According to another advantageous embodiment of the invention, direct escape of the fuel vapors from the compensator reservoirs into the environment can be reliably prevented if the compensator reservoirs are arranged within the fuel tank. The connecting points of the lines to the compensator reservoirs can therefore, likewise be arranged within the fuel tank. This leads to a further reduction in the escape of fuel vapors.
The ventilation device according to the invention proves to have a particularly simple structure if the compensator reservoirs, which are arranged within the fuel tank, are arranged such that one is below the other, and if the line for the operational ventilation is guided through the compensator reservoir for the line for the refuelling ventilation. By this means, the lines can be designed with one surrounding the other as soon as they leave the compensator reservoirs. The compensator reservoirs and the lines are therefore designed as a unit which is particularly simple to handle. The lines may, for example, be screwed to the compensator reservoirs or fastened to the compensator reservoirs by welding.
The invention permits numerous embodiments. In order to further clarify its basic principle, two of these are illustrated in the drawing and are described below.


The invention relates to a high-pressure fuel reservoir for a common rail fuel injection system of an internal combustion engine, with a tubular base body which has a blind bore extending in the longitudinal direction and a number of connections. In order to improve the high-pressure-tightness and the service life of the high-pressure fuel reservoir, a stopper is disposed in the closed end of the blind bore.

1. Field of the Invention
The invention relates to a high-pressure fuel reservoir for a common rail fuel injection system of an internal combustion engine, with a tubular base body which has a blind bore extending in the longitudinal direction and a number of connections.
2. Description of the Prior Art
A high-pressure fuel reservoir of the type with which this invention is concerned is described, for example, in DE 195 48 611. In common rail injection systems, a high-pressure pump, possibly with the aid of a presupply pump, supplies the fuel to be injected from a tank to the central high-pressure fuel reservoir, which is referred to as the common rail. Fuel lines lead from the rail to the individual injectors which are associated with the cylinders of an internal combustion engine. The injectors are individually triggered by the engine electronics as a function of the operating parameters of the engine in order to inject fuel into a combustion chamber of the engine. The pressure production and the injection are decoupled from each other by the high-pressure fuel reservoir. During operation, very high pressures are produced in the high-pressure fuel reservoir, which is why very high demands are placed on the high-pressure-tightness of the high-pressure fuel reservoir.
The object of the invention is to embody a high-pressure fuel reservoir of the type described above so that the high-pressure-tightness is improved and the service life is extended. In addition, the high-pressure fuel reservoir according to the invention should be simple in design and inexpensive to manufacture.
In a high-pressure fuel reservoir for a common rail fuel injection system of an internal combustion engine, with a tubular base body which has a blind bore extending in the longitudinal direction and a number of connections, the above object is attained by a stopper or plug being disposed in the closed end of the blind bore. The stopper serves to seal off the geometry at the closed end of the blind bore, which geometry is produced by the drilling tool and is unfavorable with regard to high-pressure-tightness, from the section of the blind bore that is used to contain the fuel. This offers the advantage that the geometry at the closed end of the blind bore which is unfavorable with regard to high-pressure-tightness does not have to be mechanically finished. In addition, the stopper also offers flow engineering advantages which become apparent during operation of the high-pressure fuel reservoir.
One particular embodiment of the invention is characterized in that the blind bore has a smaller diameter at its closed end than in the section of the blind bore used to contain the fuel. Predrilling with a narrower drill diameter and then redrilling the blind bore with a greater diameter improves the surface quality of the blind bore. In addition, tool wear is minimized during production of a bore of this kind that is stepped at its closed end.
Another particular embodiment of the invention is characterized in that the stopper is spherical. With regard to its sealing action, the stopper can also be the shape of a circular cylinder, among others. When the stopper is inserted, though, the stopper can rotate or tilt in the blind bore. The spherical shape facilitates the insertion of the sphere, particularly in the case of a stepped blind bore.
Another particular embodiment of the invention is characterized in that the stopper is press-fitted into the closed end of the blind bore. It is also possible to fix the stopper, e.g. with the aid of a thread or a separate fixing device, in the closed end of the blind bore. Press-fitting offers the advantage over other methods that no additional separate parts are required and the manufacturing cost is low.
Another particular embodiment of the invention is characterized in that the open end of the blind bore is closed by means of a pressure sensor. This offers the advantage that no additional high-pressure seal is required for the pressure sensor. A stopper is no longer required for the open end of the blind bore.


An example system and method for processing image data of a plurality of time-separated images of a non-rigid body to detect movement of the body involves calculating and storing, for each of a plurality of sampling points in each image, a plurality of candidate movements together with the estimated probability of each candidate. For each sampling point, the probability of each of the candidate movements is recalculated based on the stored probability of that candidate movement and the probabilities of the candidate movements at neighboring sampling points. A motion field indicative of the non-rigid body movement is generated from the recalculated probabilities.

This invention relates to a method and apparatus for processing image data, and in particular for processing a sequence of images of a non-rigid body to correct for movement of the non-rigid body between the images.
There are many applications in which it is useful to detect corresponding features in successive images of a body, for instance to allow detection of the movement of the body and to correct for movement of it. Many methods have been proposed for detecting such corresponding features. The successful detection of corresponding features in successive images allows the registration of the images, i.e. allows subsequent images to be transformed to eliminate differences caused by motion.
A common way to detect motion in successive images is to use landmark and segmentation based algorithms (also known as sparse matching). In such methods, geometric features which can be recognised in each image are matched, and these features are used to generate a transformation which can be applied to the whole image. However, this method is not useful for images which lack recognisable geometric features.
For instance, in the field of diagnosis of breast cancer, an imaging technique which is currently being explored is magnetic resonance imaging (MRI). FIG. 1 of the accompanying drawings shows schematically the arrangement for MRI of a human breast in which the patient 1 lies prone inside the main MR coil 3 on a couch 5. With this arrangement the breasts hang pendulously inside the double breast coil 7 as shown diagrammatically in FIG. 2. This technique has certain advantages as compared with, for instance, x-ray mammography, in that its use is not restricted to post-menopausal women or to breasts which do not include scar tissue, and it is also a 3-D technique (actually producing a set of vertically displaced 2-D slices). However, it does have certain problems. Firstly, abnormalities in the breast cannot be distinguished in a standard MRI image. To detect abnormalities it is necessary to inject a paramagnetic compound (typically Gd-DTPA) as a contrast agent and then scan every minute for approximately 7 minutes to monitor the take up of the contrast agent. Each scan consists of 16 slice images in, for instance, the X, Y plane as shown in FIG. 1. Because of the length of time over which imaging occurs, it is very likely that the patient will move during that time. These movements make it difficult, or sometimes impossible, to interpret the succession of images because not only are the images changing through take up of the contrast agent, but also because of movement of the patient. For instance FIG. 3(A) illustrates a pre-contrast image and FIG. 3(B) a post-contrast image in which the patient relaxed the pectoral muscle between the two images. The pectoral muscle can be seen as the darker grey tissue towards the top of the image. It can be seen that the effect of relaxation is to change the shape of the breast and cause non-rigid movement in the tissue surrounding the muscle. Such non-rigid movement is difficult to compensate for.
It will also be appreciated from FIG. 3 that the images are not of the type in which there are clearly recognisable geometric features which can help to detect the movement between images. Further, because the contrast agent is being taken up during the imaging process, features which have one level of brightness in a first image will not necessarily have the same value of brightness in a subsequent one (the image is said to be non-conservative). In fact, the features which are of most interest (abnormalities such as tumours) take up the contrast agent quicker than other tissue and so inevitably, and deliberately, will be changing in intensity between the different images.
Thus these images are of the type which require correction for motion, but which are not susceptible to normal motion detection techniques.
The present invention provides a technique for detecting and correcting successive images for movement where the movement is non-rigid-body movement and where the images may be themselves changing as a function of time. It is therefore applicable to images which have non-conservative flow, i.e. the total amount of brightness in the image changes. The invention is not only applicable to MRI techniques, but other non-conservative image flows where there is movement between images.
The present invention achieves this by calculating and storing for each of a plurality of sampling points in the image a probability map for the displacement of that point between the image and a time separated image. Thus not only one possible displacement is considered for each sampling point, but instead all are considered. This probability map, namely the probabilities that the sampling point has moved in a particular direction, is then refined in an iterative process by considering the probability maps for sampling points neighbouring it.
Thus whereas with previously proposed techniques only one "optimal" displacement vector was considered for each sampling point, with the present invention all are considered and stored for future processing. With the previous techniques a first estimate of the motion field was made based on the single optimal vector for each point, and then the field was refined by iteratively recomputing those vectors. However, in non-rigid flow there can be several plausible motions locally and so algorithms which ignore that fact can fall into local minima which do not correspond to the ultimately optimal solution during the iterative process. Because the present invention retains the fact that there are several possible alternatives to the "optimal" displacement vector, it can avoid being trapped in incorrect local minima.
Thus in more detail, the present invention provides a method of processing image data of a plurality of time-separated images of a non-rigid body to detect movement of the body, comprising the steps of:—
for each of a plurality of sampling points in each image calculating and storing a plurality of candidate movements together with the estimated probability of each candidate;
iteratively recalculating for each sampling point the probability of each of the candidate movement based on the stored probability of that candidate movement and the probabilities of the candidate movements at other sampling points; and
generating from the recalculated probabilities a motion field indicative of the non-rigid body movement.
The sampling points are set as a regular array over the image and the said other sampling points which are considered in the recalculation process are preferably neighbouring sampling points. The sampling points need not correspond to individual pixels in the image, but are preferably spaced by several pixels.
The estimated probabilities for the candidate movements are found by using a similarity measure which indicates the similarity of each sampling point to sampling points in the preceding image. The similarity measures can be converted into probabilities by simply normalising them for each sampling point so that they sum to unity. The candidate movements are, of course, the vector displacements which map the respective sampling points in the preceding image to the current sampling point.
As mentioned above a problem with non-conservative images such as MRI images when a contrast agent is being dynamically taken-up, is that points of a certain intensity in one image cannot be expected to have the same intensity in another. The present invention overcomes this problem by careful choice of similarity measure, and in particular by selecting the similarity measure from mutual information, normalised mutual information or entropy correlation coefficient.
The iterative recalculation of the stored probabilities comprises multiplying each stored probability by the product of the stored probabilities for the neighbouring sampling points. Preferably the only maximum probability for each of the neighbouring points is taken, more preferably weighted according to the difference between the candidate movement and the maximum probability movement of the neighbouring sampling point. The recalculation can also be limited to use only movements which are judged to be similar to the movement of the sampling point under consideration, for instance where the magnitude of the displacement caused by the movements differ by less than a preset amount.
The number of iterations in the recalculation can be set as desired, conveniently according to the distance between salient points in the image.
Once the probabilities of the candidate movements have been refined by the iterative process, the motion field is generated by selecting as the movement at each sampling point that candidate movement which has the maximum probability. This motion field can then be used to correct later images in the sequence by converting the motion field into a transformation which can be applied to each pixel. The motion field can be converted to a transformation either by interpolation or by fitting a parametric transformation to the motion field.
Having corrected the images it is possible to repeat the process using differently spaced sampling points, for instance more closely spaced sampling points, and preferably to do this iteratively to further refine the detection of the motion field and registration of the different images.
The invention also provides a corresponding apparatus for processing image data and the invention can be embodied as a computer program which may, for instance, be stored on a computer readable storage medium.

Method and apparatus for image processing


A graft material injector device and method are disclosed. The injector device includes an elongated injector tube and a side loading aperture for receiving graft material. A graft material loader and a cover for the side loading aperture may optionally be included.

A major cause of chronic, and often disabling, back pain is disruption or degeneration of an intervertebral disc. The spine is comprised of bony vertebrae separated by intervertebral discs. Each intervertebral disc connects adjacent vertebrae and forms a form of joint that allows movement of the vertebral column. An intervertebral disc is generally divided into two regions: the nucleus pulposus and the annulus fibrosus. The nucleus pulposus is a gelatinous-like tissue that lies at the center of the disc and provides a cushion between adjacent vertebrae. The annulus is made up of collagen fibers that form concentric lamellae that surround and contain the nucleus pulposus.
There are many causes of disruption and degeneration of intervertebral discs, which can be broadly categorized as mechanical, genetic and biochemical. Mechanical damage includes herniation in which a portion of the nucleus pulposus projects through a fissure or tear in the annulus fibrosus. Genetic and biochemical causes usually result from changes in the biochemical processes of a disc. Such changes can be attributed to genetic disorders or environmental influences. Degenerative disc condition is commonly caused by a change in the biochemical process of an intervertebral disc. Such degeneration is a progressive process that usually begins with a decrease in the ability of the nucleus pulposus to absorb water. With a loss of water content, the nucleus becomes dehydrated, resulting in a decrease of internal disc hydraulic pressure, and ultimately to a loss of disc height. This loss of disc height can cause the annulus to buckle, eventually resulting in annular fissures and ruptures. Herniation occurs when a rupture leads to protrusion of the nucleus pulposus through the annulus.
Furthermore, disc height plays an important role in the functionality of the intervertebral disc and spinal column, and changes in disc height can have both local and wider effects. On the local (or cellular) level, decreased disc height may result in increased pressure in the nucleus pulposus, which can lead to a decrease in normal cell operation and an increase in cell death and disintegration. In addition, increases in intra-discal pressure may create an unfavorable environment for fluid transfer into the disc, which can cause a further decrease in disc height.
Decreased disc height also results in significant changes in the larger mechanical stability of the spine. With decreasing height of the disc, the facet joints bear increasing loads and may undergo hypertrophy and degeneration. Decreased stiffness of the spinal column and increased range of motion resulting from loss of disc height can lead to further instability of the spine, as well as back pain.
Several disc defects may be treated by implantation of a prosthetic into the nuclear space of the intervertebral disc. Some procedures that may include insertion of a prosthetic into the disc are spinal fusion and disc repair and replacement. Prior to implantation of most prostheses, a discectomy is often performed to prepare the nuclear space for implantation of the prosthetic and, when spinal fusion is desired, to facilitate bony fusion between the vertebral bodies. Some implantation procedures may require a total discectomy in which the majority (and usually all) of the volume of the nucleus pulposus is removed. Others may require a partial discectomy in which only a portion of the nucleus pulposus is removed.
Traditionally, when a fusion is the desired treatment option, there are several approaches to access the disc space and position an implant to regain the proper disc height. For a typical posterior surgical approach, an incision is made through the back of a patient and access to the disc space is achieved. Manual instruments are used and inserted through the access to the intervertebral disc requiring treatment. The curettes and rongeurs are used to cut, tear, and remove nucleus pulposus tissue one piece at a time, and the rasps are utilized to roughen or scrape the endplates of adjacent vertebrae. Other options have been disclosed previously to provide a more accurate and minimally invasive discectomy such as disclosure "Disc preparation tools and methods using the same" U.S. Application Ser. No. 62/021,960, filed Jul. 8, 2014.
Once the disc has been removed, the implantation of the intervertebral implant device can be achieved. Such devices and methods have also been previously disclosed in application "Device for treating the Spine" U.S. application Ser. No. 12/035,298, filed Feb. 21, 2008, and more particularly, in application "Spinal fusion implants and devices and methods for deploying such implants" U.S. application Ser. No. 13/803,322, filed Mar. 14, 2013 and incorporated by reference herein.
A further component needed in the fusion process to create bony fusion between the two vertebral bodies and that is bone graft material or bone filler material (both of which are generally referred to herein as graft material). Such material will favor the creation of a bony bridge that spans across the implant and connects the inferior (lower) cartilaginous endplate of the superior (upper) vertebral body to the superior (upper) cartilaginous endplate of the inferior (lower) vertebral body.
Traditionally, the graft material (bone graft material and/or bone filler material) is positioned into the implant, such as a cage, prior to insertion into the disc space and due to this process cannot be fully optimized for best endplate to endplate contact.
In addition, previous graft delivery systems are back-loading, such that the graft material must be advanced a great distance through the barrel before it is extruded into the delivery site. More work (force applied over a greater distance) is therefore required to achieve this successfully, and often the nature of the graft material may cause significant binding when pushed over longer distances, rendering the device unusable.
Minimally invasive spinal surgery requires that all surgical tools be as small as possible to minimize tissue trauma and exposure to the surgical site. Tools to deliver bone graft that have a delivery diameter of 10 mm or less are highly susceptible to requiring large forces to deliver the bone graft material or, in the worst case, may seize entirely because of the high resistance developed when pushing materials of large, irregular grain size like autograft bone graft material. This susceptibility to seizing is aggravated by the length over which the graft must be delivered down the tool, which is typically 6 or more inches if the material is loaded at the most proximal tube position and pushed all the way to the delivery site.
Typical bone graft tools incorporate a proximal funnel, a long tube length, and a manual tamp that requires the user to tap to deliver the graft to the site. Large bone chips loaded into the tube chamber can contribute significantly to delivery resistance. To overcome the resistance, the outer diameter of the delivery tube is often quite large (>10 mm). Further, the loading of these long-bored funnels must be done at the surgical site, lest the material fall out at an undesirable location. Thus, this requires the primary surgeon to load and tamp the graft material into place.
There continues to be a need for further development and advancement in this field. For instance, in disclosure PCT publication WO 2014/158680 (incorporated by reference herein) FIG. 32 shows a cannula that extends thru the side wall of an implant device to introduce the bone graft material but no specific device or method is disclosed.

Graft material injector system and method


In a method of canceling interference, a base station selects a known highest data rate user transmission from a received first signal containing a group of user transmissions. The known highest rate user transmission may be configured as one or more frames, each frame including a control preamble and a plurality of encoded sub-frames. The control preamble and encoded sub-frames may be decoded, and the decoded sub-frames may be used for removing interference caused by the known highest rate user transmission to all remaining transmissions of the group.

1. Field of the Invention
The present invention generally relates to communications systems, and more particularly to a method for canceling interference in wireless communication systems.
2. Description of Related Art
Numerous interference cancellation technologies have been proposed over the last decade for second generation (Global System for Mobile Communications (GSM)) and third generation (cdma2000, Universal Mobile Telecommunication System (UMTS)) wireless communication systems. These technologies have focused on jointly decoding all user transmissions at a serving base station in either a concurrent or sequential manner. Actual implementation of these solutions have not proven feasible due to computational complexity, as well as performance loss in channel estimation and joint decoding of data from a large number of roughly equal power users. Additionally, these interference cancellation technologies are not backward compatible, and have imposed substantial latencies in the processing of user transmissions received at a base station.

Method of interference cancellation in communication systems


An electron beam actuated light modulator, including an actuatable mirror element carried by a pedestal and hinge portion, having an electrostatically more neutral first position and an electrostatically more charged second position, the mirror being actuatable in a first direction from the first position to the second position by charge accumulation, and is actuatable in a second direction from the second position to the first position by dissipation of the charge accumulation and a stop element positioned adjacent the mirror element in the first position, configured to limit movement of the mirror element in the second direction after the mirror reaches the first position traveling in the second direction.

The invention relates to spatial light modulators. More specifically, the invention relates to spatial light modulators including an array of light-modification elements which are individually controllable, and analogous to image pixels.
Micro-devices configured as light modulators have found application in a number of areas of technical endeavor. These include, but are not limited to, computing and data storage, displays, and telecommunications. Arrays of light modifying elements are conventionally fabricated by CMOS-compatible processes on silicon. The cost of CMOS-based circuits is usually high, and the reliability can be low due to a need of many layers of thin-film process-created structure. The size of conventional elements in such an array, and thus the resolution of the device, is typically limited by the manufacturing process.

Electron-beam actuated light modulator with a mechanical stop

Hewlett-Packard Development Company, L.P.


A decoding power aware encoding method for generating a predictively encoded data stream, in which predictions, that result in a reduction in the amount of data transferred from the secondary memory to primary memory during the decoding process, are favored, said method for favoring certain predictions comprising: a model for transfer of data from secondary memory to primary memory in the decoding process; a scheme for weighting the relative merits of favoring a certain prediction and the associated loss in compression gain; and based on said weighting scheme, choosing a particular prediction from the candidates allowed by the compression scheme.

Standard video decompression algorithms, such as MPEG-2, MPEG-4, H.263 use a temporal prediction scheme, which is explained below. One common feature of these schemes is a big external memory for storing video frames at different levels of decoding. Actual platforms to run various decoding algorithms vary from standard CPUs to dedicated hardware as well as various combinations of the above. Whether the decompression scheme implementation is based on a standard CPU or a dedicated hardware solution, the price of accessing external memory is heavy in terms of both real-time and system power. Both these characteristics are very important for modern communication systems. The complexity of multimedia algorithms increases from generation to generation. For example, the newest video decoding algorithm H.264 also known as MPEG-4 Part-10) is three time more complex than "initial" MPEG-4 Part-2. Although video quality is by far superior in H.264 case, there are very serious problems in implementing this algorithm on existing platforms, whether it be a standard CPU or dedicated hardware. There is not enough real-time performance to address growing demand for resolution, frame rates and lower bandwidth. In order to increase the real-time performance of such platforms frequency of processing can be increased but it causes higher dissipated power and higher cost of the silicon. Many of such multimedia platforms such as smart phones, PDAs, etc. are very cost sensitive; hence other performance improvement ways should be explored. Additionally, power dissipation is very important for all mobile applications, because battery life is limited and there is little added value in having a multimedia enabled PDA that is capable of playing back a multimedia clip only for few minutes. The requirements are around two hours, which is an average trip time in a train, car etc.
It is conventional practice to provide a caching scheme for video decoding to reduce power dissipation and real-time. But this scheme proposes only very specific, narrow kind of video processing to be run using internal cache. Additionally, if such cache is used by other tasks running on CPU simultaneously with video decoding, it will be contaminated by other kinds of data and the whole advantage of power and real time savings is eliminated.
Having described the above constraints for the decompression part of the video signal processing, we need to point out that there are no platform-based constraints on the compression part of it. Usually, the input material, being an advertisement, entertainment clip, etc, is compressed off-line ahead of time and just distributed to various mobile platforms. Besides producing a particular standard compliant output bitstream there are no "implementation" limitations for an encoder. It will be natural to ask whether it is possible to address decoding platform constraints during actual encoding. It is true that having additional constraints may cause quality degradation of the compression. But what if such quality decrease is very little whereas decoder side advantages are high? Unfortunately, there are no methods in the prior art that would describe decoder-platform-constrained encoding of video signals.
A temporal prediction scheme, which is common for various compression algorithms of video signals, is based on the idea that the current frame of video data being decoded is predicted from previously decoded frames. The frames from which such prediction is formed are called reference frames. In the natural display order, reference frames can either temporally precede/succeed the frame being decoded. Furthermore, most standard video decompression algorithms use a block-based prediction structure, wherein the prediction for each block of video data is formed from a corresponding block of data from a reference frame as indicated by a motion vector. In a typical video decompression system, reference frames are too large to be fully accommodated in the primary (typically on-chip) memory. So, the process of forming the prediction involves:                Moving blocks of data from the secondary (typically off-chip, external) reference frame memory to the primary (typically on-chip) memory;        Performing simple averaging and/or filtering operations on the block of data; and        Writing the predicted block back to a secondary memory.
For example, in the case of the MPEG-2 compression standard, each forward-predicted 16×16 block encoded in the frame mode needs a 17×17 block from the reference frame memory to form a suitable prediction. In the average case, it is seen that some blocks of the reference frames are used multiple times in the process of prediction and other blocks are not used at all.
Referring to FIG. 1 the operation of a conventional video decoding system in receiving and decoding compressed video information, according to the MPEG-4 standard, will now be described by way of further background. As is fundamental in the art, MPEG-4 video decoding predicts motion from frame to frame in a video sequence by way of motion vectors, which are two-dimensional vectors that provide offsets from the coordinate position from a prior, reference frame (or/and future, reference frame) to coordinates in the frame currently being decoded. The redundant, or non-moving, information from frame-to-frame is encoded by way of a transform, in this case discrete cosine transform (DCT), the inverse of which is performed by the video decoding system. The inverse transform of the redundant portion of the transmitted frame, in combination with the results of the motion vectors, produces an output frame.
According to the MPEG-4 standard, an incoming bitstream is demultiplexed in block 10, whereas decoding of motion vectors takes place in block 11 and decoding of texture is in block 14. Decoded motion vectors from block 11 are fed to Motion Compensation block 12 where needed block of information is extracted from previous reconstructed frames—block 13— according to the decoded motion vectors. Block 13 requires a big amount of memory to store reconstructed frames, which is generally implemented by means of external memory. It is impossible to keep all this huge memory inside any reasonable chip.
The actual displayable frame reconstruction takes place in block 15 where the output results of block 12 and block 14 are added with appropriate clipping.
In FIG. 1 the operation of texture decoding performed in block 14, which is firstly comprised of variable length decoding performed in block 21. The output of block 21 is fed to Inverse Scan block 22; and from block 22 the information is fed to block 23 in order to perform inverse prediction for AC and DC components. The output of block 23 is inverse quantized in block 24 and then inverse DCT takes place as a final stage of texture decoding in block 25.
A conventional algorithm for performing a video encoding is shown in FIG. 2. An input frame is processed in block 31, where motion estimation operation is performed. The exact algorithm for motion estimation usually is not standardized, and it is up to a developer to use various methods of motion estimation as long as the output bitstream from block 34 complies with a given standard. The main idea of motion estimation is to find the "best" match between processed block and any block in already encoded and decoded frames, which are stored in block 38. An encoder is supposed to do both encoding and partial decoding in order to perform motion estimation on decoded frames because decoder would have only decoded frames. Hence to avoid drift problems between an encoder and a decoder, any encoder would include decoder operations such as inverse quantization and inverse transform.
The output of block 31 is a delta frame between a current frame and previous frame/frames as well as motion vectors per video frame block. The resultant delta signal is further processed by block 32 applying usually a DCT transform or any similar function. The results of block 32 are quantized in block 33 to further reduce needed bandwidth. Motion vectors and quantized transform values are further encoded losslessly in block 34 that usually performs variable length coding or similar entropy scheme. Block 37 performs rate-control of the whole encoding scheme having a particular output bit rate target and allocating resources for motion estimation and quantization blocks. Various control parameters are transferred from block 37 to block 34 for being multiplexed into the output bitstream. Blocks 35 and 36 are performing partial decoding as described above. Rate-control mechanism in block 37 and motion estimation in block 31 are responsible for video quality given a particular target. There is no awareness of decoder implementation issues such as power dissipation on the encoding stage. The only decoder awareness is a buffer size at the input of decoder, which is normally standardized.

Power-aware on-chip memory management for video coding algorithms

International Business Machines Corporation


An overcurrent detection circuit for a power switch comprises a sampling circuit and a comparing circuit. The sampling circuit is configured to perform current sampling on the power switch using a sampling Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) and an amplifier, convert a sample current into a sample voltage and transmit the sample voltage to the comparing circuit, and clamp operating voltages of the comparing circuit and of an output circuit of the amplifier by a serially connected clamping MOSFET. The comparing circuit is configured to compare the sample voltage with a reference voltage and to output a result of overcurrent detection.

The on and off properties of a power switch, namely, a power Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET), is often used to implement efficient conversion of signals and energy in a switch power supply, a switch amplifier, a charge pump, and the like. Typically, a large current passes through a power MOSFET when the power MOSFET is on, and if the current passing through the power MOSFET exceeds the tolerance of the power MOSFET, the power MOSFET may be damaged permanently. Therefore, in order to ensure the reliability of the power MOSFET, continuous detection may be performed on the current passing through the power MOSFET, and overcurrent protection over the power MOSFET may be performed when the passing current is too large.
FIG. 1 gives an overcurrent detection circuit for the case in which an N-type MOSFET (NMOS) serves as the power switch. As shown in FIG. 1, NMOS N1 as a power switch has a ratio of N:1 in size over NMOS N2, and is in common-gate and common-drain connection with NMOS N2, with both gates connected to a first bias voltage CP1, and both drains connected to an input voltage Vin. The source of NMOS N1 is connected to the negative input of an amplifier A1, and the source of NMOS N2 is connected to the positive input of the amplifier A1 and the drain of an NMOS N3. The output of the amplifier A1 is connected to the gate of NMOS N3, which is in common-gate and common-source connection with an NMOS N4, with both sources connected to ground. The drain of NMOS N4 is connected to a resistor R1 and the negative input of a comparator OP1. One end of resistor R1 is connected to the drain of NMOS N4, and the other end of resistor R1 is connected to voltage Vin. One end of a resistor R2 is connected to the positive input of comparator OP1 and a reference current source Q1, and the other end of R2 is connected to input voltage Vin. The power terminal of comparator OP1 is connected to input voltage Vin, and comparator OP1 generates an output signal OCP.
During the operation of the overcurrent detection circuit shown in FIG. 1, as amplifier A1 is in negative feedback connection, the virtual shorting effect of amplifier A1 equalizes the voltages at the positive and negative inputs of the amplifier A1. NMOS N2 samples the current passing through NMOS N1, which is N times of the current passing through NMOS N2, where N is a positive integer. The current passing through NMOS N3 is that through NMOS N2. NMOS N4 mirrors the current in NMOS N3, resulting in a current Is passing through NMOS N4. The voltage drop across resistor R1 is R1*Is, the voltage drop across resistor R2 is R2*Ir, where Ir indicates the current supplied by reference current source Q1. When the current passing through NMOS N1 is small, the current passing through NMOS N2 is also small and R1*Is<R2Ir. The output signal OCP of comparator OP1 is low or inactive in this case; indicating no overcurrent in NMOS N1. When the current passing through NMOS N1 reaches an overcurrent protection threshold, or R1*Is>R2Ir, the output signal OCP of comparator OP1 is high or active; indicating that an overcurrent has occurred in NMOS N1.
There are some drawbacks to the circuit of FIG. 1. In the overcurrent detection circuit shown in FIG. 1, input voltage Vin is typically has a high voltage value, and thus each device in the circuit has to be able to tolerate higher voltages. Additionally, there will be a large error in the current Is passing through NMOS N4 obtained by current mirroring; reducing the accuracy of overcurrent detection.
Further, the amplifier A1 in FIG. 1 has a structure typically as shown in FIG. 2. The gate of NMOS N21 is the negative input, the source of NMOS N21 is connected to the source of NMOS N22, and to the ground via a current source Q21, and the drain of NMOS N21 is connected to the drain of and the gate of a P-type MOSFET (PMOS) P21, and to the gate of PMOS P22. PMOS P21 and PMOS P22 are in common-source and common-gate connection, forming a current mirroring circuit. The gate of NMOS N22 is the positive input of the amplifier, the drain of NMOS N22 is connected to that of PMOS P22 and the gate of PMOS P23. The drain of PMOS P23 is the output, and is connected to ground via current source Q22. When voltages at the positive and negative inputs of the amplifier shown in FIG. 2 are close or equal to the supply voltage, the voltages at the drain and the source of NMOS N21 are very close to each other, making NMOS N21 operate in a linear region, thereby reducing the gain of the amplifier.

Circuit and method for overcurrent detection of power switch


The receiver includes: a correlation stage (7) formed of several correlation channels (7′) for receiving intermediate signals (IF) in order to correlate them, in operating channel control loops, with the carrier frequency and specific code replicas of visible emitting satellites to be searched and tracked, each channel having a correlator (8) in which at least one integrator counter (28, 29, 30, 31) provides, at the end of each determined integration period of the correlated signals, a binary output word whose value allows detection of the presence or absence of the visible satellite to be searched and tracked; and a microprocessor for processing the data drawn, after correlation, from the radio-frequency signals. The microprocessor configures at least one unused channel placed in parallel with one of the operating channels for searching and/or tracking the same visible satellite, the unused channel being configured so that the integration period of its integrator counter is different from that of the integrator counter of the operating channel.

The invention concerns a receiver for radio-frequency signals transmitted by transmitter sources, in particular of the GPS type. The receiver has means for improving the reception dynamic of said signals for example when the signals are masked by an obstacle. Said receiver includes receiving and shaping means with frequency conversion for the radio-frequency signals for generating intermediate signals, a correlation stage formed of several correlation channels for receiving the intermediate signals in order to correlate them, in operating channel control loops, with carrier frequency and specific code replicas of visible transmitting sources to be searched and tracked, each channel being provided with a correlator in which at least one integrator counter is capable of providing, at the end of each determined integration period of the correlated signals, a binary output word whose value compared to a determined detection threshold level allows to detect the presence or absence of the visible transmitting source to be searched and tracked, and microprocessor means connected to the correlation stage for processing the data extracted, after correlation, from the radio-frequency signals. In the case of a GPS receiver, the data extracted from the signals are in particular the GPS message and pseudo-ranges.
The radio-frequency signal receiver of the present invention can of course also be used in a satellite navigation system of the GLONASS or GALILEO type. Likewise, the receiver could be used in a mobile telephone network, for example of the CDMA type (Code-division multiple access). In such case, the transmitting sources are no longer satellites but base cells of the telephone network, and the processed data concerns audible or legible messages.
In the current GPS navigation system, 24 satellites are placed in orbit at a distance close to 20,200 km above the surface of the Earth on 6 orbital planes each offset by 55° with respect to the equator. The time taken by a satellite to make a complete rotation in orbit before returning to the same point above the Earth is approximately 12 hours. The distribution of the satellites in orbit allows a terrestrial GPS receiver to receive GPS signals from at least four visible satellites to determine its position, velocity and the local time for example.
In civil applications, each of the satellites in orbit transmits radio-frequency signals formed of a carrier frequency L1 at 1.57542 GHz on which are modulated a pseudo-random PRN code at 1.023 MHz peculiar to each satellite and a GPS message at 50 Hz. The GPS message contains the ephemerides and almanac data from the transmitting satellite, which are useful in particular for calculating the X, Y, Z position, velocity and time.
The PRN code (pseudo random noise), in particular of the Gold code type, is different for each satellite. This Gold code is a digital signal formed of 1023 chips which are repeated every millisecond. This repetition period is also defined by the term Gold code "epoch". It is to be noted that a chip takes the values 1 or 0 as for a bit. However, a chip in the GPS technology is to be differentiated from a bit which is used to define a unit of data.
The Gold codes defined for 32 satellite identification numbers have the characteristic of being orthogonal. By correlating them with each other the correlation result gives a value close to 0. This characteristic thus enables several radio frequency signals transmitted on a same frequency originating from several satellites simultaneously to be independently processed in several channels of the same GPS receiver.
Currently, in several daily activities, GPS receivers which are portable or incorporated particularly in vehicles are used to allow navigation data to be provided to users. This data facilitates orientation towards the desired target and allows users to have the knowledge of their bearings. Moreover, portable GPS receivers are of smaller size so as to enable them also to be incorporated in objects which can easily be transported by one person, such as in cellular telephones or in wristwatches. However, in these objects of small dimensions, it is often necessary to minimise the energy consumed by the receiver, as they are powered by a battery or accumulator of small size.
A GPS receiver needs to pick up the radio-frequency signals transmitted by at least four visible satellites in order to determine in particular its position and time related data. However, the receiver can pick up the almanac data peculiar to each satellite by locking on individually to one of the visible satellites.

Radiofrequency signal receiver with means for improving the reception dynamic of said signals


A memory self-testing system, apparatus, and method are provided which allow for testing for a plurality of bit errors and passing memory arrays having an error level which is correctable using selected error correction coding. An exemplary system embodiment includes a memory array, a comparator, an integrator, and a test control circuit. The memory array is adapted to store input test data and output stored test data during a plurality of memory read and write test operations. The comparator compares the input test data and the stored test data for a plurality of bit positions, and provides a corresponding error signal when the stored test data is not identical to the input test data for each bit position of the plurality of bit positions. The integrator receives the corresponding error signal and maintains the corresponding error signal for each bit position during the plurality of test operations. The test control circuit provides a fail signal when a predetermined level of corresponding error signals have been provided for the plurality of bit positions.

A semiconductor data storage device, such as a random access memory ("RAM"), static random access memory ("SRAM"), dynamic random access memory ("DRAM"), synchronous dynamic random access memory ("SDRAM"), magnetic random access memories ("MRAMs"), electronically erasable programmable read-only memory (EEPROM), and other forms of a memory, are designed to store data in a memory array of memory "cells". Each memory cell, consisting of one or more transistors per bit of storage, is programmed during a write operation and is capable of maintaining the stored data, with or without memory refresh cycles, depending upon the type of memory. The memories may be included in any type of integrated circuit ("IC"), such as an IC that substantially contains only a memory array, as a dedicated memory IC, or included as an "embedded" memory as part of an IC containing additional, other circuits, such as embedded RAM, DRAM, SDRAM, etc., with a processor, digital signal processor, controller, wireless telecommunication IC or other communication IC.
A memory array is defined by a number of transistors, forming memory cells, generally arranged in a grid pattern having a plurality (or series) of rows and columns. Rows are typically utilized to select one or more data words, with the columns providing the input (for a memory write operation) and output (for a memory read operation) for each bit of each such word.
Memory arrays are tested in a wide variety of ways. External probe tests typically provide for continuity testing, and for testing of some AC and DC parameters. Many of these tests utilize one or more test patterns, in which test data is stored in the memory, read from the memory and then compared with the original test data. Typical patterns, for example, are all 1's, all 0's, checkerboard, stripe, marching, galloping, sliding diagonal, waling, and ping-pong, and test time varies with the selected pattern. Different patterns are also operative to detect different faults and failure modes during testing, such as "stuck at" faults, pattern sensitivity (such as interference and bit-line imbalance faults), multiple writing, refresh sensitivity, open and short circuits, leakage current faults, sense amplifier recovery, access time, voltage bump failures, decoder failures, and other faults and defects.
Self-testing, rather than external probe testing, has also been incorporated into many memory ICs, through the addition of additional test circuitry within the IC. Prior art built-in self-testing, however, typically determines whether there are no faults, thereby "passing " the memory as acceptable, or determining that there is at least one fault, and thereby "failing" the memory as unacceptable. Such prior art self-testing does not differentiate between memory ICs which have a single memory defect, such as a defect affecting a single bit, and multiple memory defects (affecting at least two bits), such as a defect affecting a plurality of bits.
A representative, prior art memory self-testing circuit 10 is illustrated in FIG. 1. Input test data is compared, bit position by bit position (i.e., by corresponding column), with the stored test data from the memory 20 under test, in comparator 50. In the event that the stored data does not match the test data at a given bit position, an output indicating such a failure (such as a logic 1 or high voltage state) is provided on one of the corresponding comparator output lines 55. Prior art memory self-testing circuits (such as 10) are incapable of differentiating multiple bit errors from a single bit error (such as one error versus multiple errors) because, following comparison of test data with stored data, any indicator of failure for a bit position is typically "OR'd" (OR gate 60) with the indicators of all other bit positions. If any one bit position has a failure, the output of the OR gate 60 will indicate a failure. The outcome from the OR gate 60 is then latched (with feedback) (latch 65), so that once a failure has occurred, it will not be overwritten, and the failure indicator 70 will indicate a memory failure. As a consequence of the OR process, the self-testing circuit provides information that at least one error has occurred, but cannot determine that more than one error may have occurred.
Other types of memory testing are also utilized in the prior art, such as testing which may be used with memory ICs having redundant or "spare" portions of the memory array. In such testing, memory ICs having no errors may be fully passed, and memory ICs having one or more bit errors may be "conditionally passed", in a first tier of testing. Those memory ICs which have been conditionally passed may then be physically repaired by disabling one or more rows or columns having defects, and substituting new rows or columns from the additional, redundant hardware available in the memory IC, potentially followed by additional testing. This testing requires tracking of any defect of every cell of the array. Moreover, the ability to utilize or repair such conditionally passed ICs is not assured by a definitive count or other test control criteria. More particularly, memory ICs having up to a predetermined level of bit errors cannot be fully and automatically passed, as those memories may or may not be repairable in fact. In addition, such testing requires the availability of spare or redundant parts of a memory IC, increasing memory size requirements without increasing the actual available memory. Such testing may also require several levels of testing, the initial conditional testing, followed by repair and potentially additional testing.
These current self-testing modes also do not utilize and take advantage of error correcting capabilities which may be available in the coding process for the data to be stored in the memory. Such error correcting capabilities are typically utilized to correct for "soft" errors, such as memory read errors which may occur due to external interference, such as from cosmic rays, other forms of background radiation, or other noise sources. As a consequence, by only detecting that there is at least one bit error, prior art memory self-testing fails memory ICs having a single defect, even though the single bit error could be corrected through error correction codes. By not differentiating between levels or amounts of potential defects, the prior art memory self-testing results in discarding memory ICs which are, in fact, capable of being utilized within IC error specifications. Such prior art memory self-testing, therefore, decreases the available IC yield from IC manufacturing.
As a consequence, a need remains to provide a built-in self-testing circuit for a memory array which can differentiate between levels or amounts of potential defects. Such a built in memory self-testing circuit should provide for detecting bit errors, and for differentiating memory ICs having bit errors which are correctable within the capability of a selected error correction code from memory ICs having bit errors which are not correctable or which otherwise exceed the capability of the selected error correction code. Such a built in memory self-testing circuit should not require additional, redundant memory, should not require defect tracking by specific memory cell, and should provide a definitive rather than conditional test result.

Built-in self test for memory arrays using error correction coding


Systems and methods which provide data communication content delivery through a hybrid network implementation are disclosed. A hybrid network configuration may utilize a broadcast communication technique to deliver large amounts of data communication content to one or more mobile communication device via uni-directional network links and a uni-cast communication technique via bi-directional network links with the one or more mobile communication device to facilitate delivery and utilization of the data communication content. Data content delivery loss recovery techniques implemented according to embodiments of the invention utilize network links of the hybrid network other than or in addition to the uni-directional network links to implement loss recovery techniques such as a hybrid repeat technique, a hybrid retransmission technique, hybrid statistical feedback technique, and/or combinations thereof.

The use of data communication for delivery of various content, including digital data, documents, media (e.g., images, sound, etc.), multimedia, (e.g., images and sound), etc., has become nearly ubiquitous in recent years. One common architecture for providing such data communication includes a first data communication device and a second data communication device which are configured to communicate with each other over a network providing one or more data communication channel. Such data communication channels can be hard-wired or wireless. Examples of hard-wired data communication channels include broadband cable and digital subscriber line (DSL). Examples of wireless communications channels include Edge, 3G, 4G, WiMAX and Wi-Fi.
In one example of the use of data communication, a mobile communication device, such as a smart phone, a personal digital assistant (PDA), a tablet device, a portable personal computer (PC), can communicate with a centralized system, such as a web server, application server, database server, etc., providing data to and/or accepting from the mobile communication device via a network. The network may include a combination of communication channels utilized in providing data communication between the mobile communication device and the centralized system. For example, the mobile communication device may communicate with a broadband cellular station of the network using an Edge, 3G or 4G communication channel. The cellular station may then pass the communication along to a network router over a fiber-optic or T-carrier line. The network router may then pass the communication along to the centralized system over a broadband cable or DSL connection. That is, one or more different communication channels of the network may be utilized to provide the network link between the mobile communication device and the centralized system.
A number of communication techniques, including various data-cast techniques and recipient signaling techniques, may be utilized in providing such data communications. For example, data communication may be provided using a uni-cast data-cast technique, whereby the data is transmitted as a uni-cast data stream by a first communication device (e.g., the aforementioned centralized system) to a particular second communication device (e.g., the aforementioned mobile communication device). Alternatively, data communication may be provided using a multi-cast data-cast technique, whereby the data is transmitted as a multi-cast data stream by a first communication device (e.g., the aforementioned centralized system) to a plurality of selected communication devices (e.g., specifically identified first and second mobile communication devices). Data communication may likewise be provided using a broadcast data-cast technique, whereby the data is transmitted as a broadcast data stream by a first communication device (e.g., the aforementioned centralized system) to a plurality of receiving communication devices (e.g., first and second mobile communication devices desirous of receiving the data, although not specifically identified for providing data to by the centralized system).
The foregoing data streams may be transmitted using various recipient signaling techniques. For example, feedback techniques may be utilized between a receiving communication device and a transmitting communication device to provide acknowledgment of receipt of individual data packets and/or request for retransmission of particular data packets which were not received or which otherwise contained data which is unsatisfactory to or unusable by the receiving data communication device. Such feedback techniques may utilize appreciable network resources (e.g., communication bandwidth, processing cycles, etc.) and introduce data latency, and thus are often impractical where a large number of receiving communication devices are involved (e.g., primarily useful with respect to uni-cast communications or multi-cast communications with a relatively small number of receiving communication devices). Alternatively, feedback between a receiving communication device and a transmitting communication device may not be used in favor of blind transmission of data, thereby avoiding utilizing network resources for acknowledgments, requests for retransmission, and retransmission of data (e.g., particularly useful with respect to broadcast communications or multi-cast communications with a relatively large number of receiving communication devices). However, such blind transmission techniques can result in missing data or data which is unusable by the receiving communication device, without providing any way for the receiving communication device to obtain the missing or unusable data. Accordingly, systems utilizing blind transmission are often configured to accommodate a worst case, or expected worst case, situation. For example, a transmitting communication device may implement transmission data redundancy at a level sufficient to meet an expected worst case. Such a configuration may, however, result in unnecessary utilization of network resources, such as where the worst case situation is not experienced.
It should be appreciated that, although there may several different types of communication channels in a network, typical systems operate to utilize a single network link (perhaps comprised a multiple communication channels) for a data communication session between a first and second communication device regardless of which of the foregoing communication techniques may be utilized. Moreover, the network links provided with respect to a number of data communication device pairings (e.g., the network link between the first communication device and second communication device and the network link between the first communication device and third communication device) may utilize a number common network devices. These common network devices may be used by several users at once and, therefore, demands on the common network device's bandwidth may be great. For example, in an urban environment, hundreds of mobile communication device users may simultaneously access a single cellular data node. Since the cellular data node has limited capacity to carry data, there may be restrictions on the bandwidth available to each user. This problem is particularly aggravated when the mobile device users attempt to access large data files, such as media files. Thus, these common network devices often become data bottlenecks and ultimately restrict the usability of the system, particularly with respect to certain types of data communication.
Recently, this bottleneck problem has been exacerbated by an increased popularity of streaming media content, such as Internet-based TV, movies, and music. This streaming media content is most often transmitted "over the top" of the standard communication channels, meaning that the regular bandwidth of the communication channel may be heavily consumed by a small number of users, leaving the remaining users to contend for the leftover bandwidth. In order to combat this problem, some Internet service providers have started restricting bandwidth usage and/or charging additional fees for high consumption. By way of example, a mobile communication device may be restricted to a 2 to 4 gigabyte limit on downloads within a specified period, such as a month. Other methods include pay-as-you-go, meaning that the user simply pays for bandwidth on a per-unit basis. For example, a user may be charged a few cents per megabyte of downloaded content.
As it turns out, much of the heavy network traffic is not unique to a particular user or communication device in many situations. Often users tend to consume similar types of content files. For example, each mobile device may require the same operating system upgrades periodically released by an operating system developer. In another example, certain video content tends to "go viral," meaning that the content becomes very popular among a large number of users within a short period of time. In other cases, such as with regular television programming, regular groups of users may be interested in viewing the content within a given time period.
One solution proposed for the delivery of such widely consumed data communication content is to implement a datacast network for large file downloads as described in U.S. Pat. No. 6,622,007 to Linden. Linden describes a system where media files are broadcast to a remote device over a wireless broadcast network using blind transmission techniques. The broadcast includes an ancillary data channel (e.g., non-real-time media file download) broadcast in the same broadcast channel (i.e., the same communication link) as a primary data channel (e.g., real-time program). The remote device then extracts and stores the data of the ancillary data channel for subsequent output to a user. The datacast system disclosed by Linden includes several disadvantages. For example, the system only operates asynchronously, meaning that the media file downloaded from the data cast network cannot be used in real time. Moreover, the datacast system of Linden relies only upon blind transmission broadcast techniques to deliver both the primary data channel and ancillary data channel.

Systems and methods for hybrid content delivery


The present invention provides a positive electrode active material for a lithium ion battery with excellent battery characteristics can be provided. The positive electrode active material for a lithium ion battery is represented by the following composition formula:Li(LixNi1-x-yMy)O2+α(in the formula, M represents at least one selected from Sc, Ti, V, Cr, Mn, Fe, Co, Cu, Zn, Ga, Ge, Al, Bi, Sn, Mg, Ca, B, and Zr, 0≦x≦0.1, 0<y≦0.7, and α>0).

As a positive electrode active material of a lithium ion battery, a lithium-containing transition metal oxide is generally used. Specifically, lithium cobaltate (LiCoO2), lithium nickelate (LiNiO2), lithium manganate (LiMn2O4) and the like are used, and in order to improve characteristics (high capacity, cycle characteristics, storage characteristics, reduced internal resistance, or rate characteristics) or safety, using them as a composite is under progress. For large scale application like loading in an automobile or road leveling, the lithium ion battery is now required to have characteristics that are different from those required for a cellular phone or a personal computer.
For improvement of characteristics of a battery, various methods have been conventionally employed. For example, Patent document 1 discloses a method of producing a positive electrode material for a lithium secondary battery, which is characterized in that lithium nickel composite oxide having the composition represented by LixNi1-yMyO2-δ (0.8≦x≦1.3, 0<y≦0.5, M represents at least one element selected from a group consisting of Co, Mn, Fe, Cr, V, Ti, Cu, Al, Ga, Bi, Sn, Zn, Mg, Ge, Nb, Ta, Be, B, Ca, Sc and Zr, and δ corresponds to either a deficient oxygen amount or an excess oxygen amount, and −0.1<δ<0.1) is passed through a classifier to separate those having large particle diameter from those having small particle diameter such that equilibrium separation particle diameter Dh equals to 1 to 10 μm, and those having large particle diameter are admixed with those having small particle diameter with weight ratio of 0:100 to 100:0. It is described that, using the method, a positive electrode material for a lithium secondary battery with various balances between rate characteristics and capacity can be easily manufactured.    (Patent document 1) Japanese Patent No. 4175026

This patent is subject to a terminal disclaimer.

Positive electrode active material for lithium ion battery, positive electrode for lithium ion battery, and lithium ion battery


An energy storage cell (20) including: an anode (40) formed of a molten alkali metal; an air cathode (60); and an electrolyte medium (50) located between the anode and cathode.

Batteries are common household and industrial power sources familiar to almost everyone and used in a myriad of different low tech to high tech devices and applications. Batteries are used in flashlights, radios, laptop computers, personal medical devices such as hearing aids and insulin pumps, energy storage units for electrical grids and solar energy sources, and vehicles. Batteries may be single use, throwaway batteries, which are used once and discarded, or rechargeable batteries that may repeatedly be charged to store electrical energy and discharged to provide useful electrical current.
A battery comprises at least one, and typically many, energy storage units, referred to as "cells" that are configured to store electrical energy and are controllable to release the energy to provide power. While there are many different types and configurations of cells, many of the most common cells typically comprise an anode and a cathode that sandwich an electrolyte medium between them. During discharge reactions take place in the cell. The cell converts the free energy of cell's reactions into electric energy. During discharge, at the anode a component of the anode is oxidized and at the cathode a component of the cathode is reduced.
If the anode and cathode are not electrically connected so that a current of electrons can flow from the anode to the cathode, a state of equilibrium is reached at which there is no net reaction. A potential difference between the anode and cathode at equilibrium is referred to as an "open circuit voltage (OCV)".
If on the other hand, the anode and cathode are connected by a conducting element, electrons flow from the anode to the cathode through the conducting element and ions flow through the electrolyte medium. The currents continue to flow until one of the active materials, a component of the anode that is oxidized or a component of the cathode that is reduced, is consumed, or when one of the anode or cathode is blocked by, for example, a discharge product.
If the battery is a single use, one time, throwaway battery, the discharge product cannot be converted (by charging the cell) back to its original components. If the battery is rechargeable, the discharge product or products can be converted back to their respective origins in the anode and cathode. Recharging is performed by driving a current through the battery in a direction opposite to the flow of current during discharging.
State-of-the-art lithium-ion polymer cells are considered to be the best rechargeable cells on the market. They comprise a graphitic-carbon anode and a lithium-intercalated transition-metal-oxide positive electrode. A liquid electrolyte comprising lithium salts dissolved in organic solvents and supported in a microporous-polymer separator is located between the anode and cathode. The theoretical specific energy of lithium-ion polymer battery cells is about 400 to 500 watt-hours/kg (Wh/kg).
Lithium-air cells and other alkali metal-air cells comprising an aqueous electrolyte require a relatively complicated arrangement to isolate the alkali metal from the aqueous electrolyte. US Publication US 2008/0268327, the disclosure of which is incorporated herein by reference, describes alkali metal-air cells comprising an alkali metal anode, an air cathode, an aqueous electrolyte in ionic communication with the cathode and an alkali metal cation conductive membrane that isolates the anode from the aqueous electrolyte.
Documents incorporated by reference in the present patent application are to be considered an integral part of the application except that to the extent any terms are defined in these incorporated documents in a manner that conflicts with the definitions made explicitly or implicitly in the present specification, only the definitions in the present specification should be considered.
The description above is presented as a general overview of related art in this field and should not be construed as an admission that any of the information it contains constitutes prior art against the present patent application.


According to the method, in a first step, an elastic shim element, of a part circular embodiment with a projection on the external side, is fixed around a throttle valve shaft. In a second step, a first insert and a second insert are introduced into the throttle valve support from both sides until each is in contact with the projection and between both and the relevant projection a cavity, surrounding the throttle valve shaft is formed. In a third step, a molten plastic is then introduced into the cavity through the first insert or the second insert, whereby the at least one elastic shim element is pressed with the projection thereof on the inner wall of the throttle valve support. After the plastic has hardened the first insert and the second insert are removed from the throttle valve support in a fourth step.

Methods for closing off throttle valve assemblies are known. Closing off in this case takes place by means of throttle valves which are arranged centrally in the throttle valve assembly on a throttle shaft. For as low an idling rotational speed as possible, the throttle valve must in this case be capable of closing in a highly leaktight manner, so that adverse leakage air is avoided. As regards the present-day mechanically or electrically driven throttle valve assemblies, attempts are made to achieve this by means of very narrow tolerances of the individual components. This requires a relatively high outlay in manufacturing terms for the throttle valve assembly and for the throttle valve which has to be lathe-turned with the highest possible precision to these narrow tolerances. At the same time, care must be taken to ensure that the throttle valve bears with as high a leaktightness as possible against the inner wall of the throttle valve assembly, but does not touch the inner wall too firmly, since a jamming of the throttle valve may otherwise occur.

Method for closing off a throttle valve assembly


The present invention provides a lightwave circuit device, an optical multiplexer, and an optical demultiplexer with which light can be multiplexed or demultiplexed even when a plurality of lightwaves of varying wavelength are inputted. The lightwave circuit device includes first to third Mach-Zehnder interferometers. The first to third Mach-Zehnder interferometers each have first to third ports, a first optical coupler, first and second optical waveguides, a second optical coupler, and a first heater provided along at least one of the first and the second optical waveguides. The second port of the first Mach-Zehnder interferometer and the first port of the second Mach-Zehnder interferometer are optically coupled, and the third port of the first Mach-Zehnder interferometer and the first port of the third Mach-Zehnder interferometer are optically coupled.

1. Field of the Invention
The present invention relates to a lightwave circuit device, an optical multiplexer, and an optical demultiplexer.
2. Description of the Related Art
As a lightwave circuit device, a coarse wavelength division multiplexing (CWDM) filter that makes use of a planar lightwave circuit (PLC) is disclosed is Kitoh et al., Proceedings of the 2002 IEICE General Conference, C-3-125 (2002), p. 257. With this CWDM filter, a plurality of lattice filters are disposed in tandem. This CWDM filter demultiplexes light of multiplexed wavelength into four lightwaves of different wavelengths.
As another lightwave circuit device, an optical multiplexer or optical demultiplexer in which a plurality of Mach-Zehnder interferometers are connected in a multistage tree is disclosed in Japanese Patent Application No. 2003-149472. Each of the Mach-Zehnder interferometers includes a first optical coupler, two optical waveguides connected to the first optical coupler, and a second optical coupler connected to the two optical waveguides. One of the two optical waveguides functions as a delay circuit.
The wavelengths of lightwaves multiplexed or demultiplexed by one of the above-mentioned lightwave circuit devices are predetermined for each of the lightwave circuit devices. If lightwaves whose wavelengths differ from the predetermined wavelengths are inputted to the above-mentioned lightwave circuit device, such lightwaves cannot be multiplexed. Similarly, if light in which lightwaves whose wavelengths differ from the predetermined wavelengths are multiplexed is inputted to the above-mentioned lightwave circuit device, it is impossible to demultiplex the light into individual lightwaves.


Access is provided to internal analog voltage signals on internal analog nodes of an integrated circuit, without distortion of the internal analog voltage signals. An integrated circuit includes a voltage access circuit having buffered multiplexer circuits in proximity to respective groups of internal analog nodes for respective internal analog voltage signals. Each voltage access circuit outputs a selected one of the corresponding group of internal analog voltage signals as a buffered analog node signal. The voltage access circuit also includes a buffering output circuit configured for outputting a selected one of the buffered analog node signals from the respective buffered multiplexer circuits, as a buffered voltage signal, to an output pad configured for supplying the buffered voltage signal to an external probe. Successively larger buffer stages minimize loading on the internal analog nodes, while providing sufficient power for outputting the buffered voltage signal to the external probe.

1. Field of the Invention
The present invention relates to analog voltage driver circuits configured for supplying analog voltages within an integrated circuit to an output pad for testing using an external testing device such as a high-speed oscilloscope.
2. Background Art
High-speed input/output (I/O) devices, such as physical layer transceivers (PHYs) or I/O devices, are configured for outputting digital signals on a bus in the form of analog signals having prescribed voltages according to prescribed voltage specifications. Highly integrated mixed signal designs (e.g., integrated bridge devices) for such I/O devices typically have multiple voltage domains and clock domains for both digital and analog circuitry in order to interface between different bus systems, for example a HyperTransport™ link and a PCI-X bus. For example, such I/O devices have relatively complex analog circuitry such as phase locked loops (PLL), etc. Hence, analog operations within the I/O devices need to be precisely controlled.
Process variations that are encountered during manufacture of such high-speed I/O devices into silicon-based integrated circuits often result in integrated circuits that exhibit voltage and/or timing variations due to such process variations, as well as variations caused by temperature changes or variations in supply voltages. Hence, manufacture of such I/O devices as integrated circuits requires testing and evaluation of the integrated circuit to ensure precise control of the analog signals according to the prescribed voltage specifications.
In such highly integrated mixed signal designs, however, it is quite difficult to access internal high-impedance, low capacitance analog nodes for test or debug in a flip-chip assembled die (e.g. a die having conductive bumps on a bond pad). In particular, the physical structure of an assembled die (e.g., a flip-chip assembled die) severely restricts the availability of output pads that can be used for probing internal analog voltages. Moreover, attempts to read an analog voltage signal by digitizing the analog voltage signal into a digital value, and outputting the digital value via a digital output port are not practical due to power consumption, cost of silicon area, and the bandwidth of the analog signal.
Hence, access to a large number of different analog nodes within the integrated circuit is impractical.

Voltage access circuit configured for outputting a selected analog voltage signal for testing external to an integrated circuit


A magnetic recording medium comprises a non-magnetic substrate, a lower coating layer, which is overlaid upon the non-magnetic substrate and primarily contains a binder and inorganic particles dispersed in the binder, and a magnetic layer, which is overlaid upon the lower coating layer and is constituted of at least a single layer. The magnetic layer contains at least a binder and ferromagnetic metal particles dispersed in the binder. The thickness of the magnetic layer falls within the range of 0.05 .mu.m to 0.5 .mu.m. The surface roughness of a top magnetic layer is at most 3 nm. The lower coating layer contains a fatty acid. An increase in the number of small protrusions, which have a height of at least 30 nm, does not occur substantially on the surface of the magnetic layer after the magnetic recording medium has been stored for seven days under environmental conditions of a temperature of 60.degree. C. and a relative humidity of 90%.

1. Field of the Invention
This invention relates to a magnetic recording medium. This invention particularly relates to a magnetic recording medium for use in recording a digital signal at high densities and reproducing the recorded digital signal. This invention more particularly relates to a coated type of magnetic recording medium having good storage stability.
2. Description of the Prior Art
Magnetic recording media have heretofore been used widely as sound recording tapes, video tapes, computer tapes, floppy disks, hard disks, and the like. Nowadays, there is a strong demand for the recording of magnetic information at high densities, and the recording wavelength is set to be short. Also, various recording systems, including the analog system and the digital system, have heretofore been studied.
In order to satisfy the demand for the recording of magnetic information at high densities, it has heretofore been studied to utilize thin metal film types of magnetic recording media, in which a thin metal film is employed as the magnetic layer. However, from the view point of productivity and reliability in practical use, such as corrosion resistance, it is advantageous to use coated types of magnetic recording media. The coated types of magnetic recording media comprise a substrate and a magnetic layer coated on the substrate, the magnetic layer comprising a binder and ferromagnetic particles dispersed in the binder.
The packing density of the magnetic material in the magnetic layer of the coated types of magnetic recording media is lower than the packing density in the magnetic layer of the thin metal film types of magnetic recording media. Therefore, the electromagnetic characteristics of the coated types of magnetic recording media were lower than those of the thin metal film types of magnetic recording media. However, recently, with the improvements made in ferromagnetic particles, coated types of magnetic recording media having excellent characteristics have been proposed.
In order to enhance the electromagnetic characteristics of the coated types of magnetic recording media, it is efficient, for example, to improve the magnetic characteristics of the ferromagnetic particles and to smooth the surface of the magnetic layer. In particular, as a technique for achieving the smoothing of the magnetic layer, a wet-on-wet coating technique has been used in practice. The wet-on-wet coating technique enables the enhancement of dispersibility of the magnetic particles and the formation of a very thin, smooth magnetic layer via a non-magnetic layer.
Also, with the rapid advances made in recording media in recent years, there has arisen a tendency toward long-term storage of enormous amounts of image signals and other kinds of signals. From the view point of capability of long-term signal storage, among the recording media, magnetic recording media are more advantageous than the other kinds of recording media. By the investigation of a change in magnetic characteristics and a change in input-output characteristics during long-term storage, it has been confirmed that magnetic recording media have good storage stability.
However, magnetic recording media for recording and reproducing video signals have advanced from 2-inch tapes to 1-inch tapes, to 0.5-inch tapes, and to 8 mm tapes, and the recording density has thus been set to be high. Also, the surface roughness of the magnetic layers of the magnetic recording media for recording and reproducing video signals has been set to be high. With respect to the surface roughness, it has been confirmed that the coated types of magnetic recording media have a certain level of reliability, including runnability, after long-term storage or storage under severe environmental conditions, and the coated types of magnetic recording media have the confidence of the users. However, as the coated types of magnetic recording media have been put into competition with vacuum deposited, thin-layered metal tapes (ME tapes), it has become necessary to solve the problems in that, in cases where the value representing the surface roughness of the magnetic layers of the coated types of magnetic recording media is at most 3 nm, the runnability of the coated types of magnetic recording media become low after long-term storage.
Heretofore, in order for the aforesaid problems to be eliminated, alkali and alkaline earth metals constituents have been removed as much as possible from the magnetic layer such that the formation of fatty acid Na salts and fatty acid Ca salts during the storage under environmental conditions of a temperature of 60.degree. C. and a relative humidity of 90% may be restricted. In particular, if the fatty acid Ca salts are formed in the magnetic layer, they will come out on the surface of the magnetic layer to form elevated protrusions. As a result, space loss between the magnetic recording medium and magnetic head will occur, which will result reduction of output signals. Therefore, the alkali and alkaline earth metals constituents are eliminated from the magnetic layer, and the formation of the fatty acid Ca salts is thereby restricted. However, the problems occur in that the other fatty acid metal salts, such as fatty acid Fe salts, are formed in the magnetic layer and come out to the surface of the magnetic layer, and therefore an increase in the kinetic friction coefficient of the surface of the magnetic layer still occurs after the storage under environmental conditions of a temperature of 60.degree. C. and a relative humidity of 90%. As for the problems with respect to the increase in the kinetic friction coefficient, no improvement has yet been made. It has been found that, in cases where the surface roughness of the magnetic layer is at most 3 nm, the increase in the kinetic friction coefficient of the surface of the magnetic layer after the storage occurs markedly.