1. Technical Field
This invention is directed generally to devices and methods for facilitating bone growth, and, in particular, to bone implantable devices and implantation methodologies that augment beneficial bone growth or repair while limiting bone growth in undesirable directions.
2. Background
In orthopedic and neurological surgical procedures it is often important to facilitate the growth or fusion of bony structures. This may entail growth “bone-to-bone” or, depending on the nature of the procedure, bone to device.
Chronic back problems, for example, cause pain and disability for a large segment of the population. In many cases, such problems are attributable to relative movement between vertebrae in the spine. Spinal surgery includes procedures to stabilize adjacent vertebrae. Common stabilization methods often involve fusing adjacent vertebrae together.
Fusion techniques include removing disc material that separates the vertebrae and impacting bone into the disc area. The impacted bone fuses with the bone material of the two adjacent vertebrae to thereby fuse the vertebrae together.
In a further advance in the art, spinal implants have been developed to increase the probability of a successful fusion. Such devices generally comprise a hollow cage into which bone growth inducing substances, such as bone chips or bone slurry, may be placed. The cage is inserted, either by anterior or posterior approach, into the intervertebral disc space. The cage wall has holes extending radially therethrough, typically throughout the entire cage surface. Bone growth extends into the device through the radial apertures, facilitating arthrodesis between the adjacent vertebral bone structures and allowing for the decompression of neural elements.
With the continued development of techniques for achieving spinal fusion through the use of spine fusion cages, new materials have been developed to augment the fusion process. Traditionally, the patient's own bone, or cadaver bone, was used in the cage to promote bony fusion. More recently, powerful new biologic materials have been discovered that greatly accelerate the fusion process, in some cases eliminating the need for donor bone.
However, with the utilization of the newer biologic materials there has arisen a significant problem. When bone growth inducing agents, such as bone morphogenic proteins (“BMP”), are used in cages of existing design there is risk of inducing the overgrowth of bone around and into sensitive neural tissues. This is especially the case when a posterior approach is utilized to implant a spinal fusion cage, as bony overgrowth toward the central canal or neural foramen may impinge on spinal nerve roots causing neurological damage. A recent study on posterior lumbar interbody fusion procedures using rhBMP-2 reported that 58% of patients experienced greater than expected bone formation dorsal to the fusion cage. In 30% of the cases, the bony overgrowth compromised the central canal, the neural foramen, or both. This study is confirmatory to observations first made by the present inventor in early 1999.
Typically, the bone growth agent is in liquid form and is applied to an absorbent carrier material, such as a piece of bovine collagen. The doped carrier material is placed with forceps into the interbody space, usually into an open end of the fusion cage after the cage has been implanted, but sometimes prior to cage implantation. During placement carrier material may inadvertently wipe across body areas, including internal bony structures, where bone growth is not desired. In addition, as the carrier material is pressed into place agent may squeeze out and flow into adjacent areas. Exacerbating the problem, current protocols do not encourage the use of suction, irrigation and hemostatic agents when bone growth agent is utilized. Conventional cage design also allows for the leakage of agent into undesirable areas after implantation through ill-placed apertures in the cage body, in the cage end caps, or otherwise. Because of the powerful stimulatory effects of bone growth agents, uncontrolled application of these substances may lead to serious complications, including severe inflammation, debilitating neural impingement, and other potential complications.
Thus, there is a need to better control the bone growth process when using a bone implantable device, especially in circumstances where powerful bone growth inducing agents are used in conjunction therewith.
In satisfying this need, there is also an opportunity to extend the application of bone growth agent based bony fusion to all types of bone implantable devices to better achieve union of bone-to-bone or bone-to-device, as the case may be.
Furthermore, it is desirable to eliminate the use prior art rod and screw structure that tends to interfere with a patient's musculature and tends to kill nerves and destroy segmented branch nerve extensor muscles in patients.


A Web application may include HyperText Markup Language (HTML) pages, JavaServer Pages (JSPs), servlets, resources, source files, etc. A Web archive (WAR) file is a packaged Web application that may be used to deploy a Web application into a Web server.


1. Field of the Invention
The present invention relates to an X-ray computed tomography (CT) apparatus that collects projection data by exposing X-rays to a subject and generates an image based on the projection data, and relates to a method of controlling the X-ray CT apparatus
2. Description of the Related Art
The X-ray CT apparatus includes an X-ray tube and an X-ray detector, which are arranged opposite to one another by sandwiching a subject. The X-ray CT apparatus rotates the X-ray tube and the X-ray detector about the subject while exposing X-rays from the X-ray tube and detecting, in the X-ray detector, X-rays transmitted through the subject. The data detected by the X-ray detector is collected as projection data in a data acquisition system (DAS), and the collected projection data is used to generate an image of the subject. For example, the projection data is collected by rotating the X-ray tube and the X-ray detector by 360° or (180°+fan angle) and the image is generated based on the projection data over 360° or (180°+fan angle).
A set of detection data detected at an angle relative to the subject by the X-ray detector having a plurality of detection elements is referred to as a “view”. A single rotation of the X-ray tube and the X-ray detector about the subject to collect the projection data of a plurality of views necessary to reconstruct an image is referred to as a “scan”. For example, when the projection data for 1 view is collected for each 1°, the projection data for 360 views is obtained for 1 scan and the image is reconstructed using the projection data of these 360 views.
The collection of the projection data is continuously performed by the data acquisition system (DAS) while X-rays may be intermittently exposed from the X-ray tube. When the image is reconstructed using the projection data collected by such imaging, it is necessary to reconstruct the image using the projection data collected over a period during which X-rays have actually been exposed. For example, in cardiac testing, imaging may be performed by switching the X-ray exposure on and off according to the subject's heartbeat (prospective gating scan) (e.g., Japanese Unexamined Patent Application Publication No. 2009-28065). In this case, it is necessary to reconstruct the image using the projection data collected by the data acquisition system (DAS) over a period during which X-rays have actually been exposed.
In the prior art, an X-ray detector (Ref detector) that is to be a reference is provided to the X-ray CT apparatus and a detection value (count value) detected by the Ref detector is added to the projection data for each view. Then, based on the count value detected by the Ref detector and added to each projection data for 1 view, it is determined whether X-rays have been exposed and it is thereby determined whether the projection data has been collected during a period in which X-rays have been exposed. In addition, when the exposure amount of the subject during the actual imaging is obtained, the dose is calculated by counting the views for which X-rays have been exposed.
In addition, in a scan mode in which X-rays are exposed while modulating the X-ray output (mA), the level of X-ray output (mA) can be judged by a detection value detected by the Ref detector but the actual X-ray output value (mA value) cannot be judged. Therefore, the dose is calculated using the X-ray output value that has been set by the X-ray CT apparatus during imaging planning.
In the prior art, by setting a threshold relative to the detection value (count value) of the Ref detector, it is determined whether the projection data for each view has been collected during a period in which X-rays have been exposed. However, the count value of the Ref detector is varied according to each Ref detector. In addition, the count value of the Ref detector is varied according to the conditions for X-ray exposures. Therefore, it is difficult to set a threshold suitable for determining whether X-rays have been exposed or not. For example, it is necessary to take into consideration the individual differences of the Ref detectors and the variations in the individual differences of the X-ray tube. In addition, the count value of the Ref detector is varied according to the tube voltage. Therefore, it is difficult to set a suitable threshold. In addition, by taking into consideration the offset value of the Ref detector and the data acquisition system (DAS), it is necessary to decide the threshold for determining the ON and OFF states of the X-ray exposure. Moreover, it is possible to make an error in determining the ON and OFF states of the X-ray exposure if the X-ray tube is unstable and may, for example, instantaneously generate a discharge or undergo current fluctuations.
If there is an error in determining the ON and OFF states of the X-ray exposure, the number of views necessary for reconstruction may not be obtained or the image may be reconstructed using the projection data of views that have been collected when the X-rays were in the OFF state.
Furthermore, using the detection value (count value) of the Ref detector makes it possible to determine only the ON and OFF states of the X-ray exposure. In a scan mode in which the X-ray output (mA) is modulated, the actual X-ray output value cannot be judged. Therefore, it is difficult to accurately calculate the actual exposure dose.


Field of the Invention
Embodiments of the present invention relate generally to computer processing and, more specifically, to automated techniques for retrofitting devices.
Description of the Related Art
Decreases in prices and increases in the availability of electronics have led to a proliferation of “smart” devices. Smart devices implement more powerful and flexible functionality and/or connectivity than “legacy” devices. For example, a smart thermostat can be configured to control a heating system based on sensor inputs or via a smartphone. By contrast, legacy thermostats are typically configured to control a heating system based on only a single temperature setting that is entered manual via control buttons situated on the thermostat. Although many users would benefit from the additional functionality and connectivity that come with smart devices, users oftentimes do not replace functioning legacy devices with smart devices for various practical or emotional reasons, such as the cost of purchasing the smart devices, the time and effort to replace the legacy devices, and/or emotional attachments to the legacy devices, to name a few. Instead, in many instances, users attempt to retrofit their legacy devices to enable the legacy device to implement additional or different functionality or connectivity.
To retrofit a given legacy device, a user typically designs a proxy interface that provides the desired functionality and connectivity when attached to the legacy device. For example, the proxy interface could include actuators that are configured to manipulate legacy controls based on inputs that are received from a smartphone. One drawback of this approach, however, is that designing a proxy interface is typically a complex, multi-step process. First, the user has to define the high-level behavior for the proxy interface. The user then has to identify and purchase multiple component instances, such as sensors, actuators, microcontrollers, etc. Subsequently, the user has to design and manufacture an enclosure that houses the component instances and, when attached to the legacy device, enables the component instances to manipulate the legacy controls to execute the desired high-level behavior. Lastly, the user has to assemble the component instances into a circuit. In addition, if the proxy interface includes a programmable instance, like a microcontroller, then the user has to write, compile and upload the firmware used to control the operation of the circuit through the programmable instance.
As the foregoing illustrates, designing a proxy interface requires significant knowledge across a range of technical areas, such as enclosure design and fabrication, circuit design, and programming. A lack of knowledge in one or more of these areas can discourage a user from attempting to retrofit a legacy device. Further, because the design and assembly process involves many different, manual operations, designing proxy interfaces can be tedious and time consuming, irrespective of the technical expertise of the user.
As the foregoing illustrates, what is needed in the art are more effective techniques for retrofitting legacy devices with new features and functionalities.


Venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), is a common cardiovascular disorder that affects up to 2 million patients in the U.S. each year. VTE is a significant risk in surgical patient populations where preoperative, operative, and postoperative immobilization may lead to blood stasis. VTE, when poorly treated, may lead to the development of post-thrombotic syndrome (PTS), with symptoms including chronic leg pain, swelling, and ulcers. As a consequence of PTS, many individuals struggle with a reduced quality of life.
Current treatment options for VTE include anticoagulation, catheter-direct thrombolysis (CDT) and pharmacomechanical thrombectomy. However, the efficacy of these methods is disputed. One deficiency of these methods is the use of thrombolytic agents, which may present a risk of internal bleeding, including the potential for an intracranial bleeding event. In particular, such agents are effective because they cause blood thinning and prevent coagulation. However, their use can cause bleeding complications. The use of methods involving thrombolytic agents may also be ineffective to treat against blood clots in larger veins, such as veins located in a patient's leg. Many thrombolytic agents are also costly, and logistically complicated to use.
As an alternative, mechanical compression devices that compress or squeeze portions of a patient's body to force blood flow have been used. But such devices include their own drawbacks. Oftentimes, these kinds of devices are bulky and may impose a considerable burden on hospital staff. Patients are also less inclined to ambulate while using these devices because they typically are burdensome to remove and reapply. Many patients also dislike using mechanical compression systems because such devices are typically uncomfortable. In addition, these kinds of compression devices also may not be effective at treating thrombosis in larger veins.
Accordingly, there is a need for a device that is designed to effectively treat thrombosis in large veins without using thrombolytic agents.


1. Field of the Invention
The invention relates to the area of electronic design automation (EDA), and more particularly to optical proximity correction of sub-micron mask designs.
2. Description of Background Art
A fabrication mask or reticle is used when fabricating a semiconductor device. Such a mask has a light-transparent portion (e.g., glass) and a light-shielding portion (e.g., chromium) that define a circuit pattern to be exposed on a wafer. Such patterns may define diffusion regions or field oxidation regions provided on a substrate. They may also define gate electrode patterns at a polysilicon level or a metal line patterns at any metallization layer of a chip. The mask and reticle must have a precisely defined circuit pattern. Photolithography is a process used for patterning semiconductor wafers during the manufacture of integrated circuits, such as application specific integrated circuits (ASICs).
The reticle is placed between a radiation source producing radiation of a pre-selected wavelength and a focusing lens which may form part of a xe2x80x9cstepperxe2x80x9d apparatus. Placed beneath the stepper is a resist covered silicon wafer. When the radiation from the radiation source is directed onto the reticle, that fraction of the radiation passing through the glass projects onto the resist covered silicon wafer. In this manner, an image of the reticle is transferred to the resist. For further information on IC fabrication and resist development methods, reference may be made to a book entitled Integrated Circuit Fabrication Technology by David J. Elliott, McGraw Hill, 1989.
Light passing by the edge of a reticle pattern feature (e.g., the boundary between a chromium coated region and a transparent region) will be diffracted, so that rather than producing a very sharp image of the feature edge, some radiation diffracts beyond the intended image boundary and into the dark regions. Hence feature shapes and sizes deviate somewhat from the intended design. For ultraviolet radiation in common use today, the intensity of the diffracted radiation drops off quickly over a fraction of a micron, so the affect does not prove particularly problematic when devices have dimensions on the order of 1 micrometer. However, as device dimensions have shrunk to the submicron domain, diffraction effects can no longer be ignored.
The diffraction errors can be compensated for by increasing the thickness of various critical features on the pattern. For example, increasing the width of a line on the pattern will reduce the diffraction effects. Unfortunately, this defeats the purposes of using small critical dimension features; greater logic density and improved speed.
FIG. 1A shows a hypothetical reticle 100 corresponding to an IC layout pattern. For simplicity, the IC pattern consists of three rectangular design features. A clear reticle glass 110 allows radiation to project onto a resist covered silicon wafer. Three rectangular chromium regions 102, 104 and 106 on reticle glass 110 block radiation to generate an image corresponding to intended IC design features.
FIG. 1B illustrates how diffraction and scattering affect an illumination pattern produced by radiation passing through reticle 100 and onto a section of silicon substrate 120. As shown, the illumination pattern contains an illuminated region 128 and three dark regions 122, 124, and 126 corresponding to chromium regions 102, 104, and 106 on reticle 100. The illuminated pattern exhibits considerable distortion, with dark regions 122, 124, and 126 having their corners rounded and their feature Widths reduced. Other distortions commonly encountered in photolithography (and not illustrated here) include fusion of dense features and shifting of line segment positions. Unfortunately, any distorted illumination pattern propagates to a developed resist pattern and ultimately to IC features such as polysilicon gate regions, vias in dielectrics, etc. As a result, the IC yield is degraded or the reticle design becomes unusable.
To remedy this problem, a reticle correction technique known as optical proximity correction (xe2x80x9cOPCxe2x80x9d) has been developed. Optical proximity correction involves adding dark regions to and/or subtracting dark regions from a reticle design at locations chosen to overcome the distorting effects of diffraction and scattering. Typically, OPC is performed on a digital representation of a desired IC pattern. First, the digital pattern is evaluated with software to identify regions where optical distortion will result. Then the optical proximity correction is applied to compensate for the distortion. The resulting pattern is ultimately transferred to the reticle glass. OPC is described generally at the end of this document.
FIG. 1C illustrates how optical proximity correction may be employed to modify the reticle design shown in FIG. 1A and thereby better provide the desired illumination pattern. As shown, a corrected reticle 140 includes three base rectangular featuresxe2x80x94142, 144, and 146xe2x80x94outlined in chromium on a glass plate 150. Various xe2x80x9ccorrectionsxe2x80x9d have been added to these base features. Some correction takes the form of xe2x80x9cserifsxe2x80x9d 148a-148f and 149a-149f. Serifs are small appendage-type addition or subtraction regions typically made at corner regions on reticle designs. In the example shown in FIG. 1C, the serifs are square chromium extensions protruding beyond the corners of base rectangles 142, 144, and 146. These features have the intended effect of xe2x80x9csharpeningxe2x80x9d the corners of the illumination pattern on the wafer surface. In addition to serifs, the reticle 140 includes segments 151a-151d to compensate for feature thinning known to result from optical distortion.
FIG. 1D shows a hypothetical xe2x80x9ccorrectedxe2x80x9d illumination pattern 160 produced on a wafer surface 160 by radiation passing through the reticle 140. As shown, the illuminated region includes a light region 168 surrounding a set of dark regions 162, 164 and 166 which rather faithfully represent the intended pattern shown in FIG. 1A. Note that the illumination pattern shown in FIG. 1B of an uncorrected reticle has been greatly improved by use of an optical proximity corrected reticle.
OPC, as now practiced, involves modifying a digital representation of a reticle design such as that shown in FIG. 1A. The modification is performed by a computer such as workstation having appropriate software for performing OPC. Points separated by less than the critical dimension on the design are evaluated in sequence and corrected as necessary. Evaluation of each point requires analysis of surrounding features in two-dimensions to determine whether problematic diffraction effects are likely. If so, an appropriate correction (serif or segment removal, for example) is performed.
A problem with using OPC when performing a full mask design correction is that a substantial commitment must be made in terms of time and computing power in order to optically correct the integrated circuit design, such as an ASIC design. For example, a moderately complex integrated circuit design may require at least a few days to correct with OPC even when the OPC algorithm runs on the fastest modern workstations. Often an ASIC will be attractive to a customer only if it can be designed in a relatively short period of time. If the time committment is too great, then other integrated circuits such as programmable logic devices may look more appealing. Further, an ASIC designer may need to perform a full-mask design OPC on tens of thousands of ASIC designs annually. Accordingly, a significant time and computing commitment must be invested in order to perform OPC on all of a designer""s ASIC designs.
The computational expense of OPC can be understood by recognizing as pointed out that the correction often involves adding multiple small serifs to corners of design features and removing from, adding to, or displacing lateral sections of lines. First, these many small modifications greatly increase a pattern""s complexity. Second, the modifications are made by evaluating an initial pattern with very fine granularityxe2x80x94typically evaluating potential correction points separated by no more than about 0.02 micrometers (using a 0.25 micron critical dimension technology). Note that a typical reticle design may include about 50-100 million xe2x80x9crectanglesxe2x80x9d of average size 0.5 by 0.5 micrometers. Finally, each correction is made by evaluating the surrounding pattern features in two dimensions. For example, a decision as to whether a point under consideration should be corrected may be made only after a five by five grid of surrounding points is first evaluated.
What is needed is a system and method for efficiently and accurately performing OPC on integrated circuit designs.
The invention provides a system and method for performing optical proximity correction on an integrated circuit mask design by initially performing optical proximity correction on a library of cells that are used to create the integrated circuit. The pre-corrected cells are imported onto a mask design. All cells may be placed a minimum distance apart (e.g., about 3 to 5 times the wavelength of the photolithography light) to ensure that minimal degradation from proximity effects will occur between elements fully integrated in different cells. Alternatively, the cells may be packed more closely so long as the perimeter or interfacial regions of the cells are subjected to OPC: preferably one-dimensional OPC. Because this OPC step is limited to the perimeter or interfacial regions and is performed in one-dimension, the total computational investment in correction for any given design is minimal.
One aspect of the invention involves a method of designing an integrated circuit that may be characterized as including the following: (a) selecting optical proximity corrected cells from one or more libraries of such cells; (b) placing one or more instances of cells selected from the one or more libraries adjacent to one another in an integrated circuit design; and (c) performing optical proximity correction on an integrated circuit mask layout at an interface between the instances of the cells on the integrated circuit design. The xe2x80x9cinstancesxe2x80x9d of the cells refer to individual copies of the cells as they exist as residents of an integrated circuitxe2x80x94as opposed to as generic versions generally available in a library.
The instances of the selected cells should be closely placed on the design, preferably no further from one another than about 3 to 5 times the wavelength of radiation to be used in performing photolithography during fabrication of the integrated circuit. After they are so placed, routing lines should be provided between them. It is these routing lines, outside the domain of cell, where optical proximity correction is typically performed.
While one-dimensional optical proximity correction on the interfaces between the cell instances is preferred, the invention may also be practiced with two-dimensional OPC.
Another aspect of the invention involves computer based systems that may be characterized as including the following items: (a) a storage device; (b) a cell library, located in the storage device, and comprising a plurality of cells, each containing a predefined integrated circuit functional component; (c) a place and route tool for placing instances of specified cells, selected from the library, on an integrated circuit mask layout; and (d) an optical proximity correction module for performing optical proximity correction on interfacial regions of the specified cells as provided on the integrated circuit mask layout.
Preferably, the place and route tool is configured such that cells in the mask design are separated by a distance of no greater than about 3 to 5 times the wavelength of radiation to be shown through a reticle containing the integrated circuit mask layout during photolithography. Preferably, the optical proximity correction module is configured to perform one-dimensional optical proximity correction on the interfacial regions containing features not appearing in the specified cells.
This invention also relates to reticles containing corrected layouts as produced by the systems and methods of this invention. Such reticles are intended for use in photolithography during which the corrected design layout on the reticle is used to produce an image on a wafer under fabrication. The invention further relates to integrated circuits fabricated with corrected designs produced by the systems and methods of this invention.
The invention may be further understood with reference to the following detailed description and associated drawings.


The present invention relates to a thiol-cured epoxy composition that is particularly useful as a sealer for a joint between two substrates.
Joints often are coated with a sealer or sealant to protect the joint against the penetration of water, oil, salt spray or other potentially harmful liquids. A specific type of joint that preferably is sealed is the joint between two structural members formed by welding or bonding with a structural adhesive. One example is in the joining of lightweight metal and plastic materials in the fabrication, repair and reconstruction of automotive and truck vehicle bodies and component panels and parts such as doors and hoods.
A typical method for bonding such substrates in the automotive industry is described in U.S. Pat. Nos. 5,487,803 and 5,470,416, both incorporated herein by reference. According to this method, an inner panel is positioned within an outer panel with the edge of the outer panel extending beyond the edge of the inner panel. The edge of the outer panel is then folded or crimped over the edge of the inner panel in a process known as hemming and the resulting structure is known as a hem flange. In order to permanently secure the inner panel with respect to the outer panel of the hem flange a structural adhesive is applied between the surfaces of the panel or the two panels are welded together to form a permanent hem flange assembly. A sealer is applied to cover and protect the adhesive or weld joint after the joint has been formed.
A particular problem with sealers used in connection with adhesive joints concerns cure temperature. (Meth)acrylic-based structural adhesives are becoming increasingly popular to form hem flange joints. (Meth)acrylic-based structural adhesives typically are cured at temperatures less than 121.degree. C. (250.degree. F.). Various plastisols that only cure at temperatures greater than 149.degree. C. (300.degree. F.) are currently used as hem flange sealers. However, if the previously applied (meth)acrylic-based adhesive has not itself completely cured before it is exposed during curing of the sealer to temperatures greater than 121.degree. C. (250.degree. F.), the (meth)acrylic-based adhesive tends to volatilize, thus losing its integrity. In addition, induction curing is also becoming increasing popular. Metal substrates can warp when subjected to induction curing at the temperatures required for the cure of plastisol sealants.
Sealers also must be paintable, chemically compatible with the adhesive, exhibit good flow characteristics, adhere to the substrate and joint surface and exhibit flexibility to absorb stresses caused by joint movement. Adhesion to metallic substrates can be especially problematic due to the presence of stamping, milling and drawing oils on the surface that are the result of the joint manufacturing process.
A low temperature curable sealer that exhibits good adhesion to metallic substrates thus would be very desirable.


This invention relates to information storage systems and in particular to an information storage system having a receptacle wherein a recording cartridge containing a sheet of flexible information storage media is inserted for reading and writing information on the media.
In recording or reading information on a moving information storage media, such as a magnetic recording disc, relative motion between a magnetic head transducer used for reading and writing information and the storage media on which information is written on and read from is required. The relative velocity between the head and media interface may be, for example, 550 IPS for video and high density digital applications. To achieve maximum performance, an interface of intimate contact is provided between the head and the media surface without destruction or excessive wear of the magnetic flux responsive coating on the surface.
As contact pressure between the head and media is increased to improve performance, both media and head wear are increased. The problem is particularly severe in video applications and compounded with the medias utilized for storing single video frames on separate tracks of a magnetic disc wherein one track at a time is continuously in contact with the head to provide a continuous stationary display of a single frame. In only five minutes of playtime revolving at 3,600 RPM, for example, a track on the disc is scraped about 18,000 times by the head; the by-products are so hard and abrasive that the same materials are commonly used as lapping compounds.
To prevent failure caused by contact between the head and disc, lubricated surfaces and/or air film separations have been used. However, any separation between the head and disc caused by such lubricating fluid or air film imposes a loss of signal and hence performance. A head/disc separation equal to one wave length could cause about 54.6 db loss in the output of the replay head. Since it is desired to record wave lengths that approach 1.75 microns, the playback head voltage is reduced to 50% by only 0.19 microns of separation. On the other hand, as discussed above, reduction of separation to meet desired performance would cause the interface to be destroyed within a few seconds.
Prior art solutions to the head-to-disc interface problem have generally been of two types: flying heads in conjunction with rigid hard-surface discs and heads having large surface areas buried in soft flexible "floppy" discs. Flying head discs are very expensive and require complicated and expensive recording/playback systems. A flexible or so-called "floppy" disc reduces the handling and cost problem incurred in the flying head, rigid-disc system. Some recording/read heads for "floppy" discs are relatively large to provide an interface comprised of a large contoured head buried in the soft flexible media. The large record/read head surface area distributes the force per unit area to reduce media wear and separation loss. As the media is moved past the head, however, air collects between the head and disc surface to form an air film. The thickness of this air film is a function of head and media finishes, media stiffness, head-media penetration, head size, head surface contour, viscosity of the air and disc-head relative velocity. Because of these restraints, most flexible or "floppy" disc applications are limited to slow speed, low bandwidth digital computer applications or voice recording systems.
In U.S. Pat. No. 4,175,274, means for biasing a magnetic recording disc toward the recording head by aerodynamic pressure is described and claimed. The specific embodiment described therein is a flexible spring member affixed to the inside cover of a recording cartridge. The present invention relates to an improved embodiment for biasing the disc toward the head and maintaining an intimate head-to-disc interface.
In recording systems known in the art the head is moved vertically as well as horizontally with respect to the media. To prevent damage to the media when the head is repositioned, the head is first moved vertically away from the media, then moved horizontally to the desired track location and finally moved vertically toward the media to assume its proper position for system operation. This procedure necessitates the use of a solenoid, servosystem or other means for moving the head both horizontally and vertically, thus adding to the number of components and the expense required to operate the system.
Many information storage systems are adaptable for receiving portable cartridges containing the storage media therein. Such cartridges may include a tab, seal or other means which, when removed by the user, opens an electrical circuit in the information storage system to prevent information stored on the media from being erased. This allows the user to protect the information, but has the disadvantage of precluding subsequent erasure of the information on the media and use of the cartridge to record new information unless the tab or seal is somehow replaced.


The invention relates to encryption apparatus for audio communication through a television system. Audio security is as important as video security. With the advent of satellite links, private two-way audio channels that can be associated with a video channel are desirable, for instance for business teleconferences. Secure audio scramblers are already known for telephone lines. With video channels, however, advantage can be taken of the television system facilities to reduce the cost of scrambling the audio signal in particular by using the randomizing and synchronizing capability of video scramblers already present. Also, speech quality in the scrambling-descrambling process may be improved so as to exceed the telephone-line bandwidth. It is also important to allow for more than one audio system with the same installation.
It is known to scramble a digit stream as part of a video digital transmission system. See for instance "Digital Transmission Techniques" by G. M. Drury pp. 37-49 in IBA Technical Review (Great Britain) 1976 Vol. 9.
It is known from U.S. Pat. No. 3,958,077 of J. Ross et al. to generate pseudo-random numbers with digital shift registers. The patent also shows how to perform pseudo-random scanning in a television system.
In a scrambled television system, U.S. Pat. No. 3,717,206 of V. R. Zopf et al. shows that for subscription purposes coded signals have been associated with the transmitted video signals. This is also shown for unscrambling in U.S. Pat. No. 4,070,693 of H. B. Shutterly.
A pseudo-random generator is disclosed in U.S. Pat. No. 3,681,708 of M. E. Olmstead.
It is known from U.S. Pat. No. 3,105,114 of W. Koenig to divide into segments a signal and to introduce selected time delays between such segments for scrambling effect.
U.S. Pat. No. 3,659,046 of Angleri et al. discloses a message, in binary form, being scrambled in a pseudo-random fashion by logically combining bits.
From U.S. Pat. No. 3,731,197 of J. E. Clark it is known to sample an information-bearing signal and to read the samples in a prearranged abnormal order to obtain unintelligible secured signals.
U.S. Pat. No. 3,824,467 of R. C. French shows an audio signal divided into segments which are rearranged into a new sequence before transmission. Encoding-decoding is provided by binary pseudo-random addressing of storage devices. Each storage device transmits its stored time element while storing a new time element.
U.S. Pat. No. 3,921,151 of G. Guanella teaches dividing an audio signal into segments of equal time intervals which are temporarily stored. Scrambling of the segments by reading-out in a random pattern is achieved so that at each location there is no repetition, nor omission.
U.S. Pat. No. 3,773,977 of G. Guanella, which patent is related to aforementioned U.S. Pat. No. 3,921,151, shows the use of coinciding aperiodic cipher signals from which control signals are derived for determining the storage elements, together with automatic monitoring of the occupancy to avoid omissions, or repetitions.
It is known from U.S. Pat. No. 3,819,852 of Peter Wolf to transmit an audio signal in time-compressed form during the period of a line in the vertical blanking interval of a television system.
The object of the present invention is to add an audio scrambler to a television system, while using to a maximum extent the video installation for scrambling and unscrambling in the transmission and reception of an audio message.


The present invention is concerned with a process, and the devices for implementing it, which assures the suppression of harmful factors and permits the elimination of at least the majority of the ecologically objectionable pollutant elements--noxious or undesirable due to their toxicity, their odor, and their opaqueness--contained in the gas or liquid wastes discarded by installations manufacturing mineral fibers, and which also assures reduction of the noise produced by these same installations.
The invention is concerned with installations for the manufacturing of fiber blanket, mat padding, or boards of mineral fibers and especially glass, agglomerated by thermosetting or thermoplastic binders, which coat the fibers and/or bring about close binding between fibers in the finished product.
The binders commonly used in this type of manufacturing have a base consisting of pure or modified phenoplast or aminoplast resins, since these present advantageous characteristics for the manufacturing of agglomerated fibrous products. They are thermohardenable, soluble or emulsifiable in water, they adhere well to the fibers, and are relatively low in cost.
Generally, these binding agents are used dissolved or dispersed in water to which certain ingredients are added, in order to form the binder which is sprayed on the fibers.
Under the effect of the heat to which they are subjected during the fiber products manufacturing processes, these binders release toxic volatile elements having a perceptible pungent odor even at very weak concentrations, such as phenol, formaldehyde, urea, ammonia, and decomposition products of organic materials.
Other binders are used for certain applications due to their very low cost. Certain extracts of natural products are hardened by drying and cross linking, such as occurs with linseed oil upon oxidation. Others are thermoplastic, as for example bitumen. During the fiber binding process, they are all, at least to some extent, increased in temperature and to a temperature sufficient to cause the release of volatile elements, noxious or otherwise undesirable, among other reasons, due to their odor.
In the text below, the word "binder" will be used to designate any one or all of the binding products mentioned above, whether they are used in liquid form, dissolved or suspended in water or in other liquid, or in an emulsion.
The invention relates to that part of the installation for manufacturing agglomerated fibrous materials called the fiber collecting or forming section, which is situated immediately after the fiber production apparatus, and in which the following operations are carried out primarily:
the conveying of the fibers from the fiber production apparatus to the mat or blanket forming equipment;
the application of the binder to the fibers, the binder generally incorporating pollutant elements;
the formation of the blanket on the fiber collecting device, for which purpose the collecting device generally consists of a perforated belt;
the cooling of the fibers and of the gases used for attenuating or guiding the fibers, such cooling generally being accomplished by air induced by the gases;
the separation of the fibers from the gases and induced air by suction these fluids through the blanket being formed; and
the evacuation outside of the installation of all the elements not retained by the fiber blanket or the mat being made.
It is in the fiber collecting or forming section that large quantities of gases and water have contact with the binder which contains the pollutant elements, and are contaminated according to a pollution process which is common to all known processes for the manufacture of blankets, mats, or boards of fibers agglomerated by a binder, and which will now be described.
(a) The pollution of the gaseous effluents takes place according to the following process:
The binder is projected into the current made up of fibers and gases, coming from the fiber production apparatus, the binder being present in the form of clouds of fine droplets. Some of this binder is entrapped by the fibers, some is unavoidably deposited on the walls of the installation, and finally some is found in the gases or fumes in the form of fine droplets and in the form of vapor.
Thus two fluid contamination modes coexist, the one consisting of contamination by droplets of the binder and the other consisting of contamination by vapors of the binder. In the binder application, the binder atomization or dispersion devices used furnish particles or droplets within a very wide range of diameters. The finest droplets are not entrapped by the fibers and are drawn through the blanket being formed by the gaseous current, in which they are present in suspension.
The droplets of binder deposited on the fibers during the binder application are subjected to the kinetic effects of the gaseous current passing through the blanket being formed. A large quantity of droplets is extracted from the fibers, migrates through the blanket, and is found in suspension in the exhausted gases.
Finally, the desire to obtain a homogeneous distribution of the binder in the blanket makes it necessary to disperse the binder in the fiber and gaseous current in an area situated near the fiber production apparatus, where this current still has a well-defined geometric form but where its temperature may still be high enough so that some of the binder, or at least its most volatile components, are evaporated. These pollutant vapors mix with the gases and contaminate them.
In the text below, the word "fumes" will be used to designate the gaseous effluents which pass through the fiber blanket and are evacuated outside of the collecting unit, i.e., the gases used for attenuating or guiding the fibers, the fluids induced by these gases, and the pollutant elements in the form of droplets or vapor suspended in these fluids. It is to be understood that various features of the invention, such as treatment steps and components of the apparatus, may be employed with "fumes" having a wide range of compositions and pollutants. It is preferred to treat all components of such fumes, but various features of the invention may also be employed with gases originating in fiber production operations in which the gases have pollutant components, whether or not the pollutants have their origins in fiber binders.
(b) The functions performed by the water in a fiber collecting unit make a large degree of pollution inevitable in any installation in which binders are used.
In operation, water is used:
(1) to dilute and carry the binder when the latter is used in liquid form;
(2) to wash or scrub the fumes, an operation which consists:
(2a) of causing the largest possible amount of pollutants contained in the fumes in the form of droplets or vapor to be captured by the droplets of the scrubbing water, thus causing the pollutant charge of the fumes to be transferred to the wash water; PA1 (2b) of capturing and entraining on the walls of the collecting unit the fibers suspended in the fumes;
(3) to wash the different parts of the collecting installation (perforated belt, fume flues, etc.) in order to evacuate the binder and the fibers deposited therein.
During these operations the wash water is charged with binder components which are soluble, insoluble, or in the vapor state, and the concentration of pollutant elements may reach high values.
The foregoing description of the manner in which the fumes and the water are contaminated is based on an interpretation of measurements and observations made in actual manufacturing installations.
Data derived from such measurement and observation is herein given by way of information; but it will be understood that other data and explanations may be found and that the invention is not limited by the data given.
In all installations for the manufacturing of agglomerated fibrous products, regardless of the fiberization process used, the effluent pollution described above involves considerable quantities of effluents.
In installations equipped with devices for attenuating fibers by blowing, in which the material to be attenuated is transformed into fibers by means of high-energy jets, the quantities of fumes discharged into the atmosphere are--for the best known processes--on the order of magnitude of the following values:
100 Nm.sup.3 per kilo of fibers for the process described in the Slayter U.S. Pat. No. 2,133,236;
300 Nm.sup.3 per kilo of fibers for the AEROCOR process (Stalego U.S. Pat. No. 2,489,243);
70 Nm.sup.3 per kilo of fibers for the SUPERTEL process (Levecque French Pat. No. 1,124,489 and U.S. Pat. Nos. 3,114,618 and 3,285,723);
which, for large production plants, leads to outputs ranging from 500,000 to 1,000,000 Nm.sup.3 /hr. (In these values, Nm.sup.3 refers to the cubic meter volume at standard atmospheric pressure and room temperature.)
In installations equipped with fiber attenuating devices, in which the material to be attenuated is transformed into fibers under the effect of mechanical forces--centrifugal for example--and where a gaseous current is only used as a medium (generally flowing in an essentially horizontal direction, see FIG. 14, for example) for carrying the fibers produced towards the collecting device--the quantity of fumes given off is a little less, but nevertheless very important: for example, 30 Nm3 per kilo of fibers, for the process described in Powell U.S. Pat. No. 2,577,431, which for a production plant results in outputs on the order of 300,000 to 400,000 Nm.sup.3 /hr.
The quantities of polluted water are pretty much the same for all processes, and on the order of 1,000 m.sup.3 /hr. or more for large industrial installations.
The volume of these quantities of polluted effluent has led legislatures first to limit the concentration of phenol compounds in the effluents discarded in the atmosphere, and later to prohibit discarding of any pollutants, at least in certain countries.
Furthermore, limitations concerning the odors or the opaqueness of discharged effluents have been established in various countries.
In addition, installations for the manufacture of agglomerated fibrous products also tend to pollute in another respect. In addition to toxic or pungent-smelling products, these installations discard substantial quantities of steam, on the order of 20 to 30 metric tons per hour for large plants, which steam escapes from stacks in very opaque plumes.
Noise is another type of nuisance created by installations for the manufacturing of agglomerated fibrous products. In these installations, the noise is essentially emitted by two sound sources--the apparatus for producing the fibers and the fan for extracting the fumes.
Actually, all the equipment for producing fibers mounted in these installations uses jets of gases at high speed either for transforming the material to be drawn or attenuated into fibers or for directing the fibers produced. It is known that the acoustic power level emitted by these jets considerably increases with the speed of the jets. This level may exceed 100 decibels adjacent to the fiber production apparatus, where the operators are required to work. This level is much higher than the level tolerated by industrial regulations in many countries.
Furthermore, the acoustic power developed by the fume extraction fan is transmitted along the flues connecting with the fume exhaust stack. The latter is ordinarily situated outside the buildings, where it functions as an antenna, and radiates this acoustic power into the surrounding environment. The inconvenience resulting for the vicinity has caused authorities in different countries to order the shut-down of certain installations.
The need to reduce or eliminate the pollution produced--and this at costs low enough not to overly influence the cost price of the finished product--is pressing. Numerous investigations have been carried out on this problem, and certain solutions have been developed.
The process according to the invention is characterized by the fact that the fumes (as hereinabove defined) are partially recycled, so as to cause them repeatedly to traverse the blanket or mat being formed. The process according to the invention is also characterized by the fact that the majority of the heat contributed by the gases coming from the fiber production apparatus and the attenuated fibrous material is transferred to the wash water, by the fact that the wash water is cooled, by the fact that the fumes are washed in water after they have traversed the blanket or mat and the fiber collecting device in order to transfer to the water some of the pollutant products contained in these fumes, by the fact that the non-recycled part of the said fumes is purified before evacuation into the atmosphere, by the fact that at least some of the wash water is recycled--a certain quantity of which has been subjected to a treatment for extracting at least a sizable fraction of the pollutant products contained in the wash water--and by the fact that the solid wastes are subjected to a purification treatment before final disposal.
The foregoing process effects cooling of the recirculation gases, which is important in making possible such recirculation. In combination with such cooling of the recirculating gases, it is preferred also to spray water on the current of fibers and gases in the receiving chamber, in order to cool the fiber and gas current. Such water spraying, with resultant cooling of the current, together with the cooling of the recirculating gases provides for reduction of the temperatures of the current notwithstanding the substantial absence of induction of ambient air by the attenuating blast.
According to a particularly important characteristic of the invention, the quantity of fumes discarded into the atmosphere is essentially equal to the quantity of gases flowing from the attenuating device.
The invention is particularly concerned with recycling the majority of the fumes in the installation, and with treating and evacuating only a small portion of the fumes--it being possible for the recycled portion to reach at least 95% of the total quantity of fumes ordinarily evacuated into the atmosphere. The quantity of fumes to be purified before discarding may thus be less than 5% of all of the fumes, which even makes it practicable to use costly purification treatment, whose effectiveness is total--as for example burning--without prohibitive energy expenditures.
Another object of the invention is to render insoluble the thermohardenable resins contained in the water. These resins are rendered insoluble, according to the invention, by means of a heat treatment--preferably at a temperature greater than 100.degree. C., and more advantageously ranging between approximately 150.degree. and 240.degree. C., and under pressure.
The application of the above process (for rendering resins insoluble) to at least some of the cooling and washing water is advantageously used to render insoluble the dissolved binder components contained in the water, in order to subsequently be able--by means of known techniques--to extract insoluble materials and thus to maintain the concentrations of the pollutant constituents in the washing and cooling waters at a level compatible with the continuous re-utilization of these waters in the installation. The wash water thus circulates in a closed circuit and any external rejection of pollutants with the wash water is eliminated.
Another object of the invention consists of a heat treatment to which the wash water is subjected--a treatment which consists of vaporizing it and of heating this vapor to a temperature sufficient so that the pollutant constituents are transformed into non-pollutant constituents.
The invention also is concerned with means for sound insulation--adjusted to the particular configurations shown--to the devices for conveying and guiding the recycled fumes, in order to reduce the noise emitted by these devices, and with a particular arrangement of the apparatus for evacuating the non-recycled fumes into the atmosphere, which reduces the noise emitted by this apparatus in the surrounding environment.
In addition to the general objectives above referred to the present invention also contemplates certain controls for the operating conditions, as pointed out just below.
In techniques of the kind briefly referred to above and described in detail hereinafter, the use of the various means for suppression of pollution, especially the recirculation of the current of the attenuating gas and also the separation of the pollutants from the recirculating gas, as by means of a water spray, may at times tend to introduce undesirable fluctuations in the conditions under which the fibers are formed or attenuated, and the condition under which the fiber blanket is formed. Because of the recirculation of a large part of the gases, it is desirable to more completely enclose the forming section, than has been customary where the suppression of pollution by recirculation of the gases is not contemplated. With the more tightly enclosed forming section and where recirculation of gases is employed for the purpose of suppression of pollution, there may be tendencies for fluctuation of both the pressure and the temperature of the gas in the forming section. The pressure will vary in accordance with the quantity of the gases which are diverted and discharged from the recirculation flow path; and in addition, the temperature will vary in accordance with a number of factors including not only the quantity of gas diversion and discharge from the recirculation flow path, but also the extent of water spraying utilized for separation of pollutants from the recirculation gases, as well as the temperature of the water used for such water spraying. Still further, variation in atmospheric conditions, for example as between summer and winter, may also influence the operating conditions with respect to both pressure and temperature.
Variable factors such as those just referred to tend to alter uniformity of fiber and fiber blanket production, particularly in the fiber formation by gas blast attenuation, since uniformity of the fibers depends in part upon uniformity of the conditions of temperature and pressure. In fact, if the temperature of the gaseous current and consequently of the fiber blanket is too high, polymerization of the binder will start prematurely, i.e., in for forming section, instead of awaiting feed of the blanket into the binder curing oven. This condition tends to reduce the mechanical properties of the products, particular their resilience.
On the other hand if the temperature of the gases and consequently that of the blanket is too low, the moisture carried by the blanket increases, and this reduces the efficiency of the curing oven, and can even lead to dimensional irregularities of the manufactured products.
Pressure variations tend to adversely influence the effectiveness of the devices used to reduce the pollution in the gases discharged through the stack. A negative pressure in the formation chamber, that is a pressure below atmospheric pressure will increase the quantity of the air penetrating into the forming section and consequently the quantity of gases to be diverted from the recirculation path and discharged. This results in an increase in the quantity of pollutants ejected into the atmosphere. A positive pressure, on the other hand, leads to leakage or discharge from the formation chamber of gases not yet treated, thereby impairing the intended suppression of pollution.
With the foregoing in mind it is contemplated according to the present invention that controls be provided for maintaining substantial uniformity of the conditions prevailing in the zones of fiber attenuation and fiber blanket formation, particularly uniformity of pressure and temperature of the gases in these zones. In addition, it is further contemplated to regulate the volume of the gas in circulation.
It is also contemplated according to the present invention that the controls for temperature and pressure be adjustable in order to establish the desired pressure and temperature levels.
Other objects and advantages of the invention, including in particular numerous specific advantages for the recycling of fumes, will be given and explained more completely below.


Social media platforms are becoming an increasingly important way to interact and engage with people, such as customers of a business. Both customers and businesses can benefit from an increase in the number of opportunities to engage through the use of social media. In particular, the benefits of engaging are particularly pronounced when a customer attends an event at the physical, geographic location of a business or event. The ability to recognize the customer's physical presence and engage with the customer in real time, can be used to enhance the customer's experience at the location, and thus is extremely valuable.
However, some techniques for determining the presence of a customer at a physical location using social media are extremely limited in their ability to effectively determine relevant location information, particularly in real time. For example, some existing techniques rely solely on social media posts with geotagged physical locations in order to determine social media activity by customers that are physically present at a location. However, techniques that rely solely on geotagged social media posts can miss the vast majority (e.g., up to about 95%) of social media activity relating to the geographic location of interest.


Digital graphic design, image editing, audio editing, and video editing applications (hereafter collectively referred to as media content editing applications or media editing applications) provide graphical designers, media artists, and other users with the necessary tools to create a variety of media content. Examples of such applications include Final Cut Pro® and iMovie®, both sold by Apple, Inc. These applications give users the ability to edit, combine, transition, overlay, and piece together different media content in a variety of manners to create a resulting media project. The resulting media project specifies a particular sequenced composition of any number of text, audio, image, and/or video content elements that is used to create a media presentation.
Various media editing applications facilitate such composition through electronic means. Specifically, a computer or other electronic device with a processor and computer readable storage medium executes the media content editing application. In so doing, the computer generates a graphical interface whereby designers digitally manipulate graphical representations of the media content to produce a desired result.
One difficulty in media editing is that a user cannot conveniently access various candidate clips for a particular section of a presentation. Typically, if a user wishes to evaluate different clips than those included in the composite presentation, the user must select from a large group of clips by iteratively accessing various media libraries.
Another difficulty in media editing is that a user cannot conveniently manage candidate clips (i.e., clips that are not included in a composite presentation) such that the clips can be easily accessed when modifying a particular section of the composite presentation. At any given time, the user may wish to associate one or more candidate clips (e.g., alternative “takes” of a scene, alternative content, etc.) with a particular section of a presentation. Thus, there is a need for a media editing application that allows a user to associate candidate clips with various sections of a composite presentation, thus allowing the user to retrieve the associated clips when evaluating a particular section of the composite presentation.


Tires, particularly commercial vehicle tires as used on trucks, must be periodically removed from service and replaced as the tires eventually wear from use. Depending upon the application and maintenance of each tire, anomalies in the tread region can also develop during use that lead to the tire being removed from service before reaching the normal useful life of the tread. Typically, such anomalies are discovered as the driver senses a change in the ride of the vehicle or a change in the tire noise during vehicle use, and removal of a tire having anomalies is frequently a subjective determination. Such anomalies can include, for example, depressions or uneven wear in the tread region, which is generally caused by unequal stress distribution laterally across the tread region. “Heel and toe” wear is a form of irregular wear that can occur in which one side of a tread element—such as the leading edge of a tread block—wears more quickly than the opposing side. An explanation of various types of irregular tire wear can be found in a guide entitled “Radial Tire Conditions Analysis Guide: A Comprehensive Review of Tread Wear and Conditions”, published by The Truck Maintenance Council (TMC).
Many different factors can contribute to irregular tire wear. For example, the operating conditions of the vehicle as well as the type of load carried can both have an impact on tire wear. In addition to the existence of many possible causes, it is common that a combination rather than a single factor will start uneven wear or cause it to increase. Determining a solution where a combination of factors is contributing can be particularly difficult.
Accordingly, a need remains to reduce the irregular wear occurring on tread elements such as e.g., tread blocks. The present invention provides one or more features than can help resist the onset and continuation of irregular wear. The onset of “heel to toe” wear is a particular concern that the present invention can be useful in addressing.


A long term evolution advanced (LTE-Advanced) network standard has been developed to provide wireless data rates of 1 Gbps downlink and 500 Mbps uplink. The LTE-Advanced network standard also offers multi-carrier transmission and reception within a single band as well as multi-carrier transmission and reception within two separate bands. Multi-carrier transmission within a single band is referred to as intra-band transmission and reception. In contrast, multi-carrier transmission and reception within two different bands is referred to as inter-band transmission and reception. LTE-Advanced technology is also known as fourth generation (4G) technology.
Major challenges are associated with realizing front end radio architectures (FERAs) that are necessary for providing multi-carrier operation using intra-band and inter-band transmission and reception. One of the major challenges pertains to transmit (TX) multi-carrier inter-modulation (IMD) products that can fall within a multi-carrier receive (RX) channel. Another major challenge pertains to RX de-sense due to the proximity of a multi-carrier TX channel. This major challenge is exacerbated by multi-carrier operation in which an offset frequency between the TX channel and the RX channel can be lower than a typical duplex frequency offset. Therefore, a need exists for a FERA having improved IMD performance.


1. Technical Field
The present disclosure relates to energy plant optimization and, more specifically, to a system and method for energy plant optimization using mixed integer-linear programming.
2. Discussion of Related Art
Large-scale commercial buildings such as skyscrapers and industrial buildings such as factories have large and complex energy generation and utilization needs. These needs include chilled water, chilled air, hot water, hot air, electrical loads, and the like. To meet these complex energy generation and utilization needs, these buildings, referred to herein as energy plants or simply plants, may include a large number of devices that utilize energy, generate energy, and/or store energy, for example, to provide for the plant's heating, cooling and electricity needs. These devices are referred to herein as energy devices and include devices that utilize energy such as water chillers, air conditioners, water heaters, and devices that utilize plant electricity. Energy devices may also include devices that generate energy such as fossil fuel-powered electrical generators, geothermal systems, solar collectors and photovoltaic cells. Energy devices may also include devices that store energy for later use such as thermal energy storage devices, batteries and the like.
Conventionally, energy systems may be activated and deactivated as needed. For example, a water chiller may activate when there is a need for chilled water and an air conditioner may activate when there is a need for cool air. However, as a plant may include a great number of energy devices, it is possible and in fact probable that many such devices expend energy to work against each other and operate in a less than ideal fashion.
Suboptimal plant energy generation, storage and usage may lead to excessive costs, unnecessarily large environmental impact, overtaxing of energy grids, and difficulty in complying with present and proposed governmental regulations.


This is a continuation of application Ser. No. 819,099, filed Mar. 4, 1997, now U.S. Pat. No. Re. 37,058, issued Feb. 20, 2001, which is a continuation of application Ser. No. 360,226, filed Dec. 20, 1994, now abandoned, which is a broadening reissue application of U.S. Pat. No. 5,173,814, issued Dec. 22, 1992 from application Ser. No. 653,100, filed Feb. 8, 1991, said application Ser. No. 653,100 being is a continuation of application Ser. No. 07/402,917, filed Sep. 5, 1989, now U.S. Pat. No. 5,001,581, issued Mar. 19, 1991, which is a continuation of application Ser. No. 201,736, filed Jun. 2, 1988, now  U.S. Pat. No. 4,894,738, issued Jan. 16, 1990, now U.S. Pat. No. Re. 35,792, issued May 12, 1998, which is a continuation-in-part of application Ser. No. 038,049, filed Apr. 14, 1987, now U.S. Pat. No. 4,843,500, issued Jun. 27, 1989, which is a continuation-in-part of application Ser. No. 767,671, filed Aug. 21, 1985, now U.S. Pat. No. 4,658,312, issued Apr. 14, 1987, which is a continuation of application Ser. No. 412,093, filed Aug. 27, 1982, now abandoned, which is a continuation-in-part of application Ser. No. 326,559, filed Dec. 2, 1981, now U.S. Pat. No. 4,519,010, issued May 21, 1985, said application Ser. No. 412,093 also being a continuation-in-part of application Ser. No. 244,971, filed Mar. 18, 1981, now abandoned, said application Ser. No. 201,736 also being a continuation-in-part of application Ser. No. 32,954, filed Mar. 31, 1987, U.S. Pat. No. 4,779,165, issued Oct. 18, 1988, now U.S. Pat. No. Re. 34,412, issued Oct. 19, 1993, which is a continuation of application Ser. No. 733,231, filed May 10, 1985, now abandoned, which is a continuation-in-part of the said application Ser. No. 412,093.


1. Field of the Invention
The present invention relates to computer networks and in particular to handling client requests in systems having multiple servers.
2. Description of Related Art
On computer networks, nodes may interact through requests for data, services, or other resources. Client nodes may generate requests and server nodes may service those requests. Nodes may be stand-alone computers, servers, or other computing devices, as well as virtual machines, threads, processes, or other network participants. To handle a greater volume of requests, a plurality of servers may be allocated to responding to one or more types of requests and the servers as a group may be referred to as a server farm. For example, a bank, ticket office, or some other organization may use a server farm to process requests from clients. The servers may be web servers on the Internet responding to web clients.
To provide coherent service to clients, state or session information may be collected and used by servers, so that their response to a given client may depend on session data for the client in the server farm. For example, session information may be used to implement a “shopping cart” used across multiple requests over one or more servers. It may be more efficient to store the session information on a single server within the server farm, rather than disperse that information, and ensure that the corresponding server services the requests from the associated client.
A typical system may have a unique session ID assigned to correspond to collected client session information. Initially, requests do not contain session IDs since there is not yet a session formed with the server farm. The first server to receive a request from a given client typically generates the session I). After a server creates a session for a client, the server generates a session ID to uniquely represent that session, and instructs the client to return the generated session ID in subsequent requests from that client. For example, a session ID may be encoded in the URLs the client is instructed to access or it may be stored in a server-generated cookie the client is instructed to send back to the server with each request.
Requests may be routed between the clients and the servers through one or more devices, which may be considered upstream from the servers and downstream from the clients. These devices may be part of the server farm or may operate within the network or other system. For example, the server farm may include one or more routers that receive the requests from the network and route them to servers.
The work that a server performs processing requests it receives is referred to as the load of that server. Depending on the allocation of requests and the processing required, the load may differ widely between servers and limit performance. Another example of upstream devices is load balancers. In order to distribute load across a plurality of servers within a server farm, load balancers may be used. Load balancers may be additional devices, may be part of other devices, or may include other functionality. For example, load balancers may receive incoming requests to the server farm and route the requests to individual servers in addition to determining where requests may be sent to better balance loads in the server farm.
In some systems, a load balancer or other device may be configured to receive incoming requests, examine them for a session ID, and then route them to the server that generated the session ID so that session information is kept on a single server within the server farm. The technique of using the session ID to select the server that will service a given request is called “sticky sessions”, “sticky load balancing”, or “sticky routing” since the presence of a session ID causes the requests associated with that session to “stick” to a specific server.
Some systems may include load balancers or other devices in the server farm that receive requests and send them to servers. These devices may maintain a mapping of session IDs to servers. These devices may then compare the session IDs with the requests to their mapping information to find the corresponding server. However, the size of the data for the mapping may be prohibitive as there may be many session IDs-at least one per client of the server farm.
In some systems, servers may provide their address, such as an Internet hostname or address, to clients so that the client or devices within the server farm, such as load balancers, may use that information to route subsequent requests using standard Internet routing protocols to the corresponding server. However, exposing the server addresses or other details of the sever farm configuration communicates information about the internal arrangement of the server farm to the client or others outside the server farm. As the client is typically a distrusted third party, exposing information about the internal operation of the server farm may be a security risk.
Alternatively, an administrator may configure a load balancer and servers with a particular ID corresponding to each server as identifying information. Servers may then include this identifying information in their session ID without revealing information about the internal structure of the server farm. However, the load balancer and server must then share data that allows the load balancer to target a specific server from the identifying information. This implementation imposes a burden on server farm administrators, as configuration information for these session IDs is then maintained for all load balancers and servers.


a. Field of the Invention
The field of the invention pertains to manifolds for splitting a fluid flow, more specifically, manifolds that uniformly split fluid from an inlet passage among a multiplicity of outlet passages.
b. Background Art
Splitting a quantity of fluid into equal portions is useful for many reasons. For example, a sample of fluid may be evenly distributed among the wells of a microtitration plate ("plate" or "microplate") or among a group of test tubes. In this manner, research may be conducted on several uniform samples at the same time, accelerating the research and allowing for direct correlation of results.
One existing method used to split a quantity of fluid into approximately equal portions involves dedicating a costly pump or syringe to each outlet passage. A common and less expensive method used for dispensing fluid into a microplate entails passing the fluid through a manifold. The instant invention relates to this latter method.
Customarily, a manifold comprises multiple ports or passages inserted into an elongated cylindrical cavity. Fluid is introduced into the cavity and subsequently dispersed through outlet ports into a receptacle (e.g., a microplate). A manifold with only two symmetrically placed outlet passages would have a nearly equal flow from its outlet passages. However, manifolds with more than two outlet passages are the most useful, and the more outlet passages, the greater the flow disparity.
In a typical manifold, the number of outlet passages is designed to match the number of wells in a single column of a microplate, which has several columns of wells. In this manner, the manifold may fill the microplate one column at a time. Thus, Manifolds having either eight or twelve outlet passages are common. The outlet passages are positioned, not necessarily symmetrically, on each side of the inlet passage. Accordingly, the flow from each of the outlet passages is not uniform in the absence of a flow modifying device such as the instant invention.
In the operation of a typical manifold for microplate dispersion applications, the manifold is first primed to eliminate the manifold's "dead volume" (i.e., the volume of fluid needed to fill the manifold before useful dispensing can start). Then, a volume of fluid equal to the volume desired for each well in a single column of the microplate times the number of outlet passages (which equals the number of wells in a single column of wells), is dispensed into the inlet passage of the manifold. Ideally, the manifold then evenly disperses the flow among the microplate wells of the column. However, the flow from the outlet passages nearest the inlet passage is typically less than the flow from the outlet passages most distant from the inlet passage. This discrepant flow pattern results from the internal flow dynamics of the manifold, which must be adjusted to balance the flow.


The technology is known that controls a welding electric current in a high precision by performing a primary electric current control through an inverter in a welding transformer of resistance welding device (referring to a Patent document 1). Further, through devising its coil structure, a further high speed control is attempted (referring to a Patent document 1).
Resistance welding technology is widely used for the manufacture line of a car or general industries. In those industries, in order to overcome competition on a world level, improvement in productivity is indispensable.
Furthermore, development of the energy-saving technology which cuts down CO2 from the viewpoint of earth-environment protection is also an urgent subject. However, the conventional resistance welding method for the steel plate with bad weld ability was presenting the aspect which moved against productivity or energy saving. The various resistance welding methods that it was suitable for such various uses are developed (referring to a Patent document 1,2,3,4).


In the papermaking industry, it is generally known that paper to be converted into a consumer product such as paper towels, bath tissue, facial tissue, and the like is initially manufactured and wound into large rolls. By way of example only, these rolls, commonly known as parent rolls, may be on the order of 10 feet in diameter and 100 inches across and generally comprise a suitable paper wound on a core. In the usual case, a paper converting facility will have on hand a sufficient inventory of parent rolls to be able to meet the expected demand for the paper conversion as the paper product(s) are being manufactured.
Because of the soft nature of the paper used to manufacture paper towels, bath tissue, facial tissue, and the like, it is common for parent rolls to become out-of-round. Not only the soft nature of the paper, but also the physical size of the parent rolls, the length of time during which the parent rolls are stored, and the fact that roll grabbers used to transport parent rolls grab them about their circumference can contribute to this problem. As a result, by the time many parent rolls are placed on an unwind stand they have changed from the desired cylindrical shape to an out-of-round shape.
In extreme cases, the parent rolls can become oblong or generally egg-shaped. But, even when the parent roll is are only slightly out-of-round, there are considerable problems. In an ideal case with a perfectly round parent roll, the feed rate of a web material coming off of a rotating parent roll can be equal to the driving speed of a surface driven parent roll. However, with an out-of-round parent roll the feed rate can likely vary from the driving speed of a surface drive parent roll depending upon the radius at the web takeoff point at any moment in time.
With regard to the foregoing, it will be appreciated that the described condition assumes that the rotational speed of the parent roll remains substantially constant throughout any particular rotational cycle of the parent roll.
If the rotational speed remains substantially constant, the feed rate of a web material coming off of an out-of-round parent roll will necessarily vary during any particular rotational cycle depending upon the degree to which the parent roll is out-of-round. In practice, however, parent rolls are surface driven which means that if the radius at the drive point changes, the rotational speed can also change generally causing variations in the feed rate. Since the paper converting equipment downstream of the unwind stand is generally designed to operate based upon the assumption that the feed rate of a web material coming off of a rotating parent roll will always be equal to the driving speed of the parent roll, there are problems created by web tension spikes and slackening.
While a tension control system is typically associated with the equipment used in a paper converting facility, the rotational speed and the takeoff point radius can be constantly changing in nearly every case. At least to some extent, this change is unaccounted for by typical tension control systems. It can be dependent upon the degree to which the parent roll is out-of-round and can result in web feed rate variations and corresponding tension spikes and slackening.
With an out-of-round parent roll, the instantaneous feed rate of the web material can be dependent upon the relationship at any point in time of the radius at the drive point and the radius at the web takeoff point. Generally and theoretically, where the out-of-round parent roll is generally oblong or egg-shaped, there will be two generally diametrically opposed points where the radius of the roll is greatest. These two points will be spaced approximately 90° from the corresponding generally diametrically opposed points where the radius of a roll is smallest. However, it is known that out-of-round parent rolls may not be perfectly oblong or elliptical but, rather, they may assume a somewhat flattened condition resembling a flat tire, or an oblong or egg-shape, or any other out-of-round shape depending upon many different factors.
Regardless of the exact shape of the parent roll, at least one point in the rotation of the parent roll exists where the relationship between the web take off point radius and the parent roll drive point radius that results in the minimum feed rate of paper to the line. At this point, the web tension can spike since the feed rate of the web material is at a minimum and less than what is expected by the paper converting equipment downstream of the unwind stand. Similarly, there can exist at least one point in the rotation of the parent roll where the relationship between the web take off point radius and the parent roll drive point radius results in the maximum feed rate of paper to the line. At this point, the web tension can slacken since the feed rate of the web material can be at a maximum and more than what is expected by the paper converting equipment downstream of the unwind stand. Since neither condition is conducive to efficiently operating paper converting equipment for manufacturing paper products such as paper towels, bath tissue and the like, and a spike in the web tension can even result in a break in the web material requiring a paper converting line to be shut down, there clearly is a need to overcome this problem.
In particular, the fact that out-of-round parent rolls create variable web feed rates and corresponding web tension spikes and web tension slackening has required that the unwind stand and associated paper converting equipment operating downstream thereof be run at a slower speed in many instances thereby creating an adverse impact on manufacturing efficiency.
While various efforts have been made in the past to overcome one or more of the foregoing problems with out-of-round parent rolls, there has remained a need to successfully address the problems presented by web feed rate variations and corresponding web tension spikes and web tension slackening.


Intraluminal, intracavity, intravascular, and intracardiac treatments and diagnosis of medical conditions utilizing minimally invasive procedures are effective tools in many areas of medical practice. These procedures are typically performed using imaging and treatment catheters that are inserted percutaneously into the body and into an accessible vessel of the vascular system at a site remote from the vessel or organ to be diagnosed and/or treated, such as the femoral artery. The catheter is then advanced through the vessels of the vascular system to the region of the body to be treated. The catheter may be equipped with an imaging device, typically an ultrasound imaging device, which is used to locate and diagnose a diseased portion of the body, such as a stenosed region of an artery. For example, U.S. Pat. No. 5,368,035, issued to Hamm et al., the disclosure of which is incorporated herein by reference, describes a catheter having an intravascular ultrasound imaging transducer.
FIG. 1a shows an example of an imaging transducer assembly 1 known in the art. The imaging transducer 1 is typically within the lumen 10 of a guidewire (partially shown), having an outer tubular wall member 5. To obtain an image of a blood vessel, the imaging transducer assembly 1 may be inserted into the vessel. The transducer assembly 1 may then rotate while simultaneously emitting energy pulses, e.g., ultrasound waves, at portions of the vessel from within the vessel and receiving echo or reflected signals.
Turning to FIG. 1b, it is known in the art that an imaging console 20 having a display screen, a processor and associated graphics hardware (not shown) may be coupled with the imaging transducer assembly 1 to form a medical imaging system 30. The imaging console 20 processes the received echo signals from the imaging transducer assembly 1 and forms images of the area being imaged. To form the images, the imaging console 20 draws multiple lines, known as “radial lines”, (not shown) on the display screen that each correspond to an angular position of the transducer assembly 1. The processor of the imaging console 20 assigns brightness values to pixels of the lines based on magnitude levels of the echo signals received from the transducer assembly 1 at the angular positions corresponding to the lines. A drawing that includes a large number of these radial lines results in an image such as an intravascular ultrasound (IVUS) image (not shown). Such an image may show, among other things, the texture of the area being imaged, such as the smoothness or the roughness of the surface of the area being imaged.
An example of an image 70 having a large range of magnitudes and a number of texturally distinct regions 80 is shown in FIG. 1c. Texture and the correct discrimination of the underlying surface are important in medical imaging. Such information is helpful to radiologists and other clinicians who seek to diagnose pathology. It is often the case in medical imagery that an abnormality is detectable only as a subtle variation in texture. Accordingly, an improved system and method for detecting and presenting such textural information would be desirable.


1. Field of the Invention
The present invention relates to a common rail that is mounted to a pressure accumulation fuel injection system and accumulates high-pressure fuel.
2. Description of Related Art
A common rail 101 of a related art will be described with reference to FIG. 14. The common rail 101 is a pressure accumulator for accumulating high-pressure fuel pumped from a high-pressure fuel pump (supply pump or the like) and has an accumulation chamber (central hole) 123 formed therein for accumulating the high-pressure fuel therein. The common rail 101 has pipe joints 121 to be connected with external pipes (a high-pressure pump pipe, an injector pipe, and the like). A center portion of an outer end of the pipe joint 121 communicates with the accumulation chamber 123 through an inside-outside communication hole 124 (branch hole).
An orifice 130 for reducing pressure pulsation caused by an injection operation of an injector or an orifice 130 for reducing pressure pulsation caused by pumping operation of the high-pressure fuel pump is formed in the inside-outside connection hole 124. The orifice 130 of the related art is formed by directly drilling a main body 120 (hereinafter referred to as a rail main body) of the common rail 101. The orifice 130 is formed in the deepest portion of the inside-outside connection opening 124 because of constraints concerning the drilling. That is, as shown in FIG. 14, the orifice 130 opens in the accumulation chamber 123.
High-pressure fuel is accumulated in the accumulation chamber 123 and therefore high pressure is applied to the inner peripheral surface of the accumulation chamber 123. The orifice 130 having a small diameter opens in and crosses the inner peripheral surface of the accumulation chamber 123. A portion of the opening that crosses the inner peripheral surface is hereinafter referred to as a crossing hole. As the crossing hole becomes smaller, a larger stress is concentrated at the edge of the opening of the crossing hole. Therefore, a common rail, in which the orifice 130 is integrally formed in the rail main body 120 by the drilling, is used for a pressure accumulation fuel injection system of a small size vehicle or the like, in which accumulation pressure of the accumulation chamber 23 is comparatively low (for example, 180 MPa or under).
In recent years, it has been required to increase the common rail pressure to 180 MPa or over also in the small size vehicle for the purpose of improving exhaust performance and the like. However, a common rail having the orifice 130 integrally formed in the rail main body 120 by the drilling has the small crossing hole, which is formed by the orifice 130, and therefore has difficulty in securing a safety factor concerning fatigue strength. Therefore, not only in a large size vehicle but also in the small sized vehicle, for the purpose of securing the safety factor concerning the fatigue strength, as shown in FIG. 3, there has been proposed a common rail 1, in which an orifice 30 is formed in a bush 31 separate from a rail main body 20 and the bush 31 is fixed in an inside-outside communication hole 24 to enlarge the crossing hole (for example, as described in Patent document 1: JP-A-2002-322965) in place of forming the orifice 130 directly in the rail main body 120.
A technology of the related art that fixes the bush 31 having the orifice 30 in the inside-outside communication hole 24 press-fits an outer peripheral surface of the bush 31 into the inside-outside communication hole 24. When the bush 31 is inserted into the inside-outside communication hole 24, there is a possibility that a press-fitting burr A is produced at an end portion (hereinafter referred to as a press-fitting end portion) of the bush 31 opposite to the press-fitting direction of the bush 31 as shown in FIG. 4A.
When the engine is driven in a state where the press-fitting burr A is produced as shown in FIG. 4A, there is a possibility that the press-fitting burr A is dropped by an action of the flow of the fuel and flows as a foreign matter to the injector. When the press-fitting burr A is dropped and flows to the injector, the press-fitting burr A clogs a filter disposed in the injector. When a small press-fitting burr A passes through the mesh of the filter of the injector, there is a possibility that the burr A enters the injector having high accuracy and causes malfunctions such as faulty sliding and faulty sealing.


In general, an ink jet recording head for use in an ink jet recording apparatus is composed of an ink jet recording head for forming droplets of a liquid such as ink, and of a supply system for supplying the ink and the like to the head.
With regard to a connection of a wiring board to a liquid discharge substrate, which are applied to the recording head, a wide-array ink jet apparatus composed of a printhead substrate in which an electrical connection electrode is present on a surface opposite to a surface having a discharge port therein has been disclosed in JP 11-192705A. In FIG. 18 and FIG. 19, a wide-array ink jet pen 210 disclosed in JP 11-192705A is shown. FIG. 18 is a perspective view of the wide-array ink jet pen having a wide-array printhead. FIG. 19 is a cross-sectional view of a part including a printhead die and a carrier substrate 220, showing electrical connection portions of the wide-array ink jet printhead of FIG. 18. The pen 210 is composed of a wide-array printhead 212 and a pen body 214. The pen body 214 is a housing to which the printhead 212 is attached. In the pen body 214, an internal chamber 216 serving as a local ink reservoir is present. Further, referring to FIG. 18 and FIG. 19, the printhead 212 includes plural printheads 218 attached to the carrier substrate 220. In each printhead 218, electrodes 284 for making an electrical connection and an ink supply port 242 are formed on the back surface side of a surface on which a nozzle opening 238 is formed. In the carrier substrate 220 for retaining the printhead 218, electrical wiring is installed on a first surface 270 and second surface 272 thereof, and on the first surface 270 side, the carrier substrate 220 makes the electrical connection with the printhead 218 by solder bumps, and is thus disposed. Further, a logic circuit (not shown) and a drive circuit 230 are mounted on the second surface 272 opposite to the first surface in the substrate 220.
Problems as described below are inherent in the ink jet recording head formed as described above, in which the ink supply port is formed on the back surface side of the surface of the liquid discharge substrate in which the nozzle opening is formed, the connection electrodes for making the electrical connection with the other members are provided in the vicinity of the ink supply port, and the electrical connection is made with the surface of the carrier substrate on which the electrical wiring is formed.
For example, in the ink jet recording head of FIG. 19, the ink supply ports individually formed in the carrier substrate and the liquid discharge substrate must be made to communicate with each other. Specifically, it is necessary to completely prevent the ink from entering the electrical connection portions and completely prevent the ink from leaking to the outside by forming a partition wall for surely separating a fluid on the periphery of the ink supply port.
For this purpose, dimensional and positional accuracies of the ink supply port of the liquid discharge substrate and the ink supply port of the carrier substrate become an important point.
In the head disclosed in JP 11-192705A, as shown in FIG. 19, the carrier substrate 220 is formed of a plate-like member with some thickness, which is formed of silicon, multilayer ceramics, or glass epoxy, such as one used for forming a hybrid multi-chip module.
Hence, since the head is poor in processability, the positional accuracy of the opening of the ink supply port 242 and the dimensional accuracy of the opening thereof are not very high, and accordingly, a displacement is prone to occur in a relative position thereof to the ink supply port of the liquid discharge substrate. This proves particularly troublesome in the case of using an adhesive or a sealing agent on the fluid partition wall of the ink supply port. In the case of such a construction, a position of the adhesive or the sealing agent is greatly affected by a position of an end of the ink supply port of the carrier substrate, and accordingly, when a position of an end surface of the ink supply port of the carrier substrate is overlapped with the position of the ink supply port of the liquid discharge substrate, there occurs such a problem that the adhesive or the sealing agent flows into the ink supply port of the liquid discharge substrate. Further, in the ink jet head, a necessity to array the plural liquid discharge substrates whose width is as narrow as possible at high density has increased from viewpoints of cost and size. Therefore, it is also necessary to form the ink supply ports of the liquid discharge substrate and the carrier substrate to be narrow in width and at high density. However, in the carrier substrate disclosed in FIG. 19, it is difficult to accurately form the ink supply ports narrow in width because the carrier substrate has some thickness.