The present invention relates porous osteoinductive nanocomposites and for the methods to prepare osteoinductive nanocomposites. The osteoinductive composites consist of biocompatible polymers and non-heated (or non-sintered), needle-shaped or plate-like calcium phosphate nanocrystals and the methods comprise the steps of: a. adding phosphate to a calcium solution thereby evoking precipitation of calcium phosphate nanocrystals; b. washing the nanocrystals with water and suspending them in an organic solvent or getting dry calcium phosphate nanocrystals after evaporating organic solvent; c. adding polymers (previously dissolved in an organic solvent) to calcium phosphate nanocrystal suspension, rotational mixing of the components using beads, mixing with porogenic agents, moulding the composite material and evaporating of the organic solvent; or mixing polymers (not dissolved in an organic solvent but raw powder), dry calcium phosphate nanocrystals and porogenic agents with melting intrusion and moulding the composites; d. leaching porogenic agents in water.

Autologous bone harvested from the patient's own bone is the gold standard bone substitute for repairing large bone defects. However, the amount of autologous bone harvestable from a patient is limited and the bone subtraction itself poses significant health risks and results in loss of structural integrity of the remaining bone.
Developments in tissue engineering have provided synthetic implants, for instance in the form of scaffold materials, which allow attachment of bone cells and ingrowth of new bone tissue and subsequent deposition of new bone mineral. The synthetic materials may either be grafted ex vivo with bone cells prior to implantation or may be implanted as naked scaffolds that attract bone cells from the periphery to the site of the implant.
Recent advances in tissue engineering have produced a variety of valuable scaffold materials. Calcium phosphates such as hydroxyapatite (HA; the mineral phase of bone), biphasic calcium phosphate (BCP) and α- or β-tricalcium phosphate (TCP) are known to possess both osteoconductive (bioactive) as well as osteoinductive properties and provide very suitable scaffold materials. The bioactive nature of calcium phosphates allows them to function as a template for new bone formation by osteogenic cells through deposition of new mineral material at the scaffold's surface and is an important feature of the scaffold material. The osteoinductive nature of calcium phosphates is a qualitative feature, i.e. the capacity to induce the development of the new bone tissue, thereby enhancing the rate of deposition of new mineral, depends on various material parameters. Bone induction is generally defined as the mechanism by which a mesenchymal tissue is induced to change its cellular structure to become osteogenic. Bone formation in scaffolding materials following ectopic implantation (i.e. intramuscular implantation or subcutaneous implantation) is generally a demonstration of osteoinduction of such scaffolding materials.
In general, porous calcium phosphates have been found to exhibit osteoinductivity. For instance, Yamasaki et al., in Biomaterials 13:308-312 (1992), describe the occurrence of heterotopic ossification (formation of new bone in tissue that does not normally ossify) around porous hydroxyapatite ceramic granules, but not around dense granules. The porous granules range in size from 200 to 600 μm, and have a continuous and interconnected microporosity of which the pores range in diameter from 2 to 10 μm.
At present there still exists a need for additional composite materials with osteoinductive properties.


A semiconductor device includes an insulating support layer on which are mounted, in succession, a conductive layer, a buried layer comprising first and second spaced portions and a semiconductor single crystal layer comprising spaced first and second portions respectively supported on the first and second spaced portions of the buried layer, the respective first and second portions having respective, first and second common sidewalls defining respective, first and second peripheries thereof and respectively comprising a transistor region and a collector electrode region. A remaining exposed surface portion of the conductive layer extends between the spaced, opposing portions of the sidewalls of the transistor and collector electrode regions. An insulating material layer is supported on the first portion remaining exposed surface portion of the conductive layer and extending between and engaging the spaced and opposed portions of the peripheral sidewalls of the transistor and collector electrode regions, and a second portion engaging and extending from the remaining portions of the peripheral sidewalls of the transistor and collector electrode regions. The conductive layer electrically couples the transistor region and the collector electrode region and further comprises an electrical interconnection layer.

The present invention generally relates to semiconductor devices and methods of producing semiconductor devices and, more particularly, to a semiconductor device such as a bipolar transistor having a means for connecting a collector layer of the bipolar transistor to a collector electrode or another circuit element, and a method of producing such a semiconductor device.
Conventionally, a bipolar transistor is provided with a device isolation structure such as a U-groove and a pn junction, for the purpose of isolating the bipolar transistor from other elements. A relatively thick field oxide layer is provided in order to reduce the capacitance between a base electrode and a collector layer, and in addition, a collector buried layer having a high impurity concentration is provided so as to connect the collector layer to a collector electrode at a low resistance.
A description will be given of a method of producing an example of a conventional bipolar transistor, by referring to FIGS. 1A through 1F.
As shown in FIG. 1A, n-type impurities are injected into a p-type semiconductor substrate 21 to form an n.sup.+ -type buried layer 22, and an n-type layer 23 is epitaxially grown on the n.sup.+ -type buried layer 22.
Then, silicon nitride layers 24 and 25 are respectively formed in a region where the transistor is to be formed and in a region where a collector electrode of the transistor is to be formed.
Next, as shown in FIG. 1B, the semiconductor substrate 21 formed with the silicon nitride layers 24 and 25 is oxidized to form a LOCOS type field oxide layer 26.
As shown in FIG. 1C, a U-groove 27 which penetrates the field oxide layer 26 and reaches the semiconductor substrate 21 is formed. This U-groove 27 penetrates the field oxide layer 26 which defines the outer periphery of the transistor. Hence, the region where the transistor is to be formed and the region where the collector electrode is to be formed are isolated from other regions. A silicon oxide layer 28 is thereafter formed on the inner surface of the U-groove 27.
Next, as shown in FIG. 1D, a polysilicon layer 29 is formed on the surface of the semiconductor substrate 21, including the inside of the U-groove 27, by a chemical vapor deposition (CVD).
Thereafter, as shown in FIG. 1E, the polysilicon layer 29 is polished to obtain a planarized surface, and the polished polysilicon layer 29 is further subjected to a controlled etching so as that the polysilicon layer 29 only remains inside the U-groove 27. In addition, the silicon nitride layers 24 and 25 are removed.
The top of the polysilicon layer 29 inside the U-groove 27 is oxidized to form a silicon oxide cap 30.
Therefore, a transistor region 31 in which the transistor is to be formed and a collector electrode region 32 in which the collector electrode is to be formed, are respectively formed by the above described process.
Next, as shown in FIG. 1F, p-type impurities and n-type impurities are successively injected into the transistor region 31 to form a base layer 33 and an emitter layer 34 of the transistor. In addition, n-type impurities are injected into the collector electrode region 32 to form a low resistance n.sup.++ -type region 35 which reaches the buried layer 22.
A base electrode 37, an emitter electrode 38 and a collector electrode 36 are respectively formed on the base layer 33, the emitter layer 34 and the low resistance n.sup.++ -type region 35.
However, the conventional method of producing the bipolar transistor has the following problems.
First, the collector layer must be formed by an epitaxial growth.
Second, since the collector layer is epitaxially grown on the collector buried layer, it is impossible to make the impurity concentration of the buried layer sufficiently high because of the need to maintain satisfactory crystal properties of the epitaxially grown collector layer. For this reason, the resistance between the collector layer and the collector electrode is relatively large.
Third, since the collector layer and the semiconductor substrate make contact over a relatively wide area, the capacitance between the collector layer and the semiconductor substrate is relatively large, thereby preventing a high-speed operation of the transistor.
Fourth, an isolating means such as a U-groove and a pn junction must be formed with a high accuracy in order to provide the necessary device isolation.
Fifth, it is essential to provide the field oxide layer in order to reduce the capacitance between the base electrode and the collector layer. However, when the LOCOS type field oxide layer is employed, the transistor region is relative deep and enlarged. As a result, the capacitance between the collector and base becomes relatively large, thereby preventing a high-speed operation of the transistor.
In other words, there are two factors limiting the operation speed of the bipolar transistor, namely, the base resistance and the base-collector (pn junction) capacitance. In order to reduce the base-collector capacitance so as to improve the operation speed, it is necessary to make the thickness of the LOCOS type field oxide layer large and reduce the area occupied by the bipolar transistor. However, the two cannot be satisfied simultaneously in a satisfactory manner. That is, when the LOCOS type field oxide layer is made thick, the so-called bird's beak is formed on the side of the field oxide layer, and the bird's beaks of adjacent field oxide layer portions connect in extreme cases, thereby making it impossible to form a transistor region between the adjacent field oxide layer portions. For this reason, it is difficult to control the width between the sides of the adjacent field oxide layer portions. Therefore, in order to control the widths of transistor region and the collector electrode region with a high accuracy, it would be preferable not to employ the LOCOS.

Semiconductor device with buried conductor and interconnection layer


A method and apparatus for replacing two separate photo detectors chips and two photo emitters by a single photo detector chip and a single photo emitter. This is achieved by using CombiDisks having a flexible shaft. The flexible section allows for the bending of the CombiDisks so that the encoder disks are next to each other and tangent to the same vertical plane. This allows for the placement of both the x and the y sensors in a single plane. This will in turn allow for the two photo detectors to be integrated in a single semiconductor chip, saving a separate photo detector chip, and its associated packaging. This additional savings is significant since the packaging itself contributes to approximately one half of the cost of such a detector.

The present invention relates to computer input devices, such as mice and trackballs. In particular, it relates to the reduction of the number of components and improvements in tracking performance.
Typically, such input devices have a ball which is rolled when a user moves the mouse across the desktop, or is manipulated with the user""s finger for a trackball. The ball is in frictional contact with various rollers. The ball""s motion is detected by two rollers that are offset from each other at an angle of 90 degrees. These two rollers which rest against the ball detect the ball""s motion in the x and y directions respectively. Each roller is typically connected to an encoder disk via a shaft, with the combination of the roller, shaft and encoder disk referred to as a xe2x80x9cCombiDisk.xe2x80x9d Each encoder disk has radial slits, which when used in conjunction with a photo emitter and a photo detector allow for the determination of the amount of movement of the ball in the x or y directions. A pressure roller is provided, which is spring biased to provide a force to keep the ball engaged with the rollers of the CombiDisks. Typically designs use anywhere from one to three pressure rollers which are spring biased and provide improved shock loading. The ball rests against the pressure roller(s) and thus does not frictionally engage the cavity in the outer housing of the input device.
One of the challenges in the design of such input devices is the reduction of costs. In the extremely competitive input device market, savings of pennies are very significant. One method to reduce costs is to simplify the design and reduce the number of components required to the build the input device.
Another challenge in the design of such devices is tracking precision. Typical CombiDisks comprising cylindrical rollers, shafts, and encoder disks are held in place on axial supports, and are susceptible to axial play when the direction of movement changes. Axial play is the CombiDisk""s axial translation with respect to its supports which is induced by the movement of the ball in a direction parallel to the axis of the CombiDisk. Typically, as the input device is moved, the ball gets rolled, and frictional forces drag the roller and hence the CombiDisk in the direction of the movement of the input device. Once the direction of the movement of the input device is changed, the CombiDisk xe2x80x9cplaysxe2x80x9d in the changed direction. This axial play adversely impacts the tracking precision of such input devices. The shaft""s longitudinal play also adds tolerances and requirements to the optical detection system to make the system insensitive to the variations of position of the disk relative to the photo emitters and detectors.
The present invention provides a method and apparatus for replacing two separate photo detector chips and two photo emitters by a single photo detector chip and a single photo emitter. This is achieved by using CombiDisks having a flexible shaft. The flexible section allows for the bending of the CombiDisks so that the encoder disks are next to each other and tangent to the same vertical plane. This allows for the placement of both the x and the y sensors in a single plane. This will in turn allow for the two photo detectors to be integrated in a single semiconductor chip, saving a separate photo detector chip, and its associated packaging. This additional savings is significant since the packaging itself contributes to approximately one half of the cost of such a detector.
The middle section of the CombiDisk is made of a highly flexible material such as spring steel, and is bent to create a spring force. This bending causes the CombiDisks to exert a spring force against the ball and hence eliminates the need to have a spring-biased pressure roller. The prior art spring-biased roller can now be replaced with a simple roller, eliminating a spring and the associated spring-bias linkage and assemblies, and hence provide for another cost savings.
The rollers on the CombiDisks in one embodiment of the present invention are conical. The conical rollers are tapered away from the encoder disks creating a ramp-like body causing the ball to want to move away from the encoder disks. Accordingly, the equal and opposite reactive force tends to move the conical roller towards the encoder disks. Since the rollers are rigidly attached to the encoder disks via a bent flexible shaft, the force created by the ball on the roller tends to push the encoder disk away from the ball. As such, the role of the conical rollers is to impart a compressive force along their axis of rotation. This force also ensures the encoder disk is always pressed against the axial stop, making the position of the disk more precise and not subject to axial play when the direction of the movement is changed.
In a preferred embodiment, CombiDisks contact the ball at 90 degrees. Each CombiDisk is comprised of a bent flexible steel shaft connecting a conical roller on one end to the encoder disk on the other. The two conical shaped rollers have a cone angle in the range of zero to 45 degrees, which is a function of the ball""s size, and are biased against the ball, with the vertex of the cone opposite to the encoder disk. A third roller, in contact with the ball, is placed equidistant from the CombiDisk rollers and on the opposite side of the ball from the encoder disks. The semiconductor chip with the photo detectors is mounted vertically on one side, and the photo emitters are mounted vertically on the other side of the encoder disks.

Computer input device with encoders having flexible shafts and conical rollers


An image sensor having image sensor pixels operable in multiple gain modes is provided. An image sensor pixel may include a photodiode, a charge transfer transistor, a reset transistor, a source follower (SF) transistor, a row select transistor, and a capacitor that is directly connected across the gate terminal and a selected source-drain terminal of the SF transistor. The SF transistor and the row select transistor may be selectively coupled to a power supply line and a column output line by asserting either a first control signal or a second control signal. The first control signal is asserted to place the pixel in a low conversion gain mode, whereas the second control signal is asserted to place the pixel in a high conversion gain mode. The charge transfer transistor may always be activated during the low conversion gain mode and may be selectively activated during the high conversion gain mode.

The present invention relates to image sensors and, more particularly, to image sensors that are used to produce high-dynamic-range images.
Image sensors are commonly used in electronic devices such as cellular telephones, cameras, and computers to capture images. In a typical arrangement, an electronic device is provided with an image sensor and a corresponding lens. Some electronic devices use arrays of image sensors and corresponding lenses to gather image data. In certain applications, such as when acquiring still or video images of a scene with a wide range of light intensities, it may be desirable to capture high-dynamic-range images. In high-dynamic-range images, highlight and shadow detail can be retained that would otherwise be lost in a conventional image.

Multimode pixel readout for enhanced dynamic range

Semiconductor Components Industries, LLC


Disclosed herein are systems and methods for electroplating nickel which employ substantially sulfur-free nickel anodes. The methods may include placing a semiconductor substrate in a cathode chamber of an electroplating cell having an anode chamber containing a substantially sulfur-free nickel anode, contacting an electrolyte solution having reduced oxygen concentration with the substantially sulfur-free nickel anode contained in the anode chamber, and electroplating nickel from the electrolyte solution onto the semiconductor substrate placed in the cathode chamber. The electroplating systems may include an electroplating cell having an anode chamber configured for holding a substantially sulfur-free nickel anode, a cathode chamber, and a substrate holder within the cathode chamber configured for holding a semiconductor substrate. The systems may also include an oxygen removal device arranged to reduce oxygen concentration in the electrolyte solution as it is flowed to the anode chamber.

Nickel electroplating operations often play an important role in semiconductor and integrated circuit fabrication processes. For instance, in a typical wafer level packaging (WLP) application, the formation of a "bump stack" may involve the electrodeposition of a relatively thin nickel layer (1-5 μm) to serve as a copper diffusion barrier between a copper seed layer or copper pillar and a solder layer formed of tin or tin-silver material. In the absence of such a diffusion barrier, the copper reacts with the solder layer and forms a very thick and weak intermetallic layer. FIG. 1A, for example, displays a cross-sectional view of the interface between a copper seed layer and a solder layer of tin-silver deposited directly thereon, and illustrates the formation of a thick intermetallic layer between the deposited solder layer and the underlying copper seed in the absence of an intervening nickel barrier layer. FIG. 1B shows a similar cross-sectional view of copper seed and solder layers but here with an intervening nickel barrier layer. FIG. 1B illustrates, in contrast to FIG. 1A, that the intermetallic layer potentially formed—here between the nickel barrier layer and the tin-silver solder layer—may advantageously be quite thin. FIG. 1A also points out several so-called "Kirkendall Voids" which oftentimes form within the thick copper/tin-silver intermetallic layer in the absence of an intervening nickel barrier layer.
In semiconductor fabrication processes, nickel electroplating is frequently performed using a nickel sulfamate-based electrolytic bath—in particular, in advanced nickel plating applications where low stress films are a requirement (such as WLP). Nickel sulfamate baths are composed of dissolved nickel sulfamate salts typically in combination with boric acid and an "anode activator" ingredient. Several commercially-available formulations will be discussed in greater detail below. Typically, the target acidity of these baths is within a pH range broadly of about 3.0 to about 5.0, and sometimes within a more limited range of 3.5 to 4.5.
Nickel sulfamate electrolytic baths are typically employed because of nickel's high solubility in sulphamic acid—meaning that a higher concentrations of dissolved nickel ions are possible than with other nickel electrolyte solutions—which can result in higher electroplating rates than may be achieved with other potential nickel electroplating solutions. In addition, nickel sulfamate electrolyte solutions are able to produce very low-stress electrodeposited films.
Nevertheless, despite these clear advantages, basic nickel sulfamate electroplating solutions (and even those containing boric acid plus an "anode activator") still fail to produce ideal films of electroplated nickel without some additional engineering of the electroplating chemistries. Chief among the remaining issues is the surface roughness of the electrodeposited film, which has been found to be associated with the formation of detrimental interfacial voids between nickel film and reflowed solder material. For instance, FIG. 1C presents two electron micrograph images showing the surface roughness of two electrodeposited nickel films and the tendency of this "roughness" to cause wafer defects. As shown in the figure, an electrodeposited nickel film having a surface roughness (Ra) of 35.6 nm is seen to result in a wafer exhibiting a large defect count relative to a wafer having an electrodeposited nickel film with a surface roughness of roughly half that at 14.2 nm.
Moreover, in a typical nickel electroplating process flow, such as that employed in a typical WLP application, multiple nickel sulfamate baths are used to sequentially plate multiple semiconductor wafers. Since deviations in bath composition can also result in inferior electroplating, poor process performance, and potential defects in the plated nickel layers, ideally, each semiconductor wafer is plated under substantially the same process conditions, relatively invariant with time and constant over the plating of numerous wafers. In practice, however, maintaining constant process conditions in nickel sulfamate baths can pose a significant challenge.

This patent is subject to a terminal disclaimer.

Methods and apparatuses for electroplating nickel using sulfur-free nickel anodes


A technique and user interface for the assignment of computer system resources and, particularly, for the assignment of storage system resources. The invention allows a user to make design selections through a user interface and, then, automatically provides an indication to the user as the effect of the selections. For example, various performance parameters for each of several applications may be displayed graphically as a chart. In response to the user adjusting a parameter for one application, the invention determines what effect this change will have on the other displayed parameters. A design for the computer system is developed. Levels of performance parameters for the design are predicted. The predicted levels of performance parameters are compared to the desired levels of performance parameters. When the predicted levels are lower than the desired levels, the design is modified. The design may be modified by reducing the desired levels of performance parameters based on utility functions. The results may then be displayed graphically on the chart. The invention is particularly useful for allocating data storage system resources among several different applications.

A computer system including a data storage system may be designed and configured for a specific application. This generally requires that a skilled designer rely on experience while making design choices based on requirements for the storage system and on possible memory devices to be incorporated into the storage system. Particularly, a variety of different memory devices form the building blocks of modern data storage systems. Specific devices can be based on, for example, optical, magnetic and/or electronic storage technologies and may include solid-state memory devices, magnetic tape drives and optical or magnetic disk drives and arrays. Memory devices can be further characterized, for example, by capacity, levels or types of redundancy provided (e.g., RAID-1 or RAID-5), bandwidth, cost, latency (e.g., read latency and/or write latency), and whether they are read and write capable, read-only capable, dynamic, static, volatile or non-volatile.
Additionally, storage capacity and other resources of the data storage system may be assigned to one or more applications that are to be served by the data storage system. For example, various data elements, such as files or databases, may be placed in a storage system in a number of different ways. One form of this may be referred to as the "bin-packing problem," the goal of which is to fit data elements of various different sizes into storage devices of given sizes, while minimizing wasted space. The assignment task quickly becomes more complicated, however, when one attempts to apply additional constraints. For example, certain applications may have minimum requirements in terms of storage capacity, access times and so forth.
Since storage system resources are most often limited, the design process typically includes making a number of trade-offs with respect to the system resources. Further, design trade-offs that are appropriate in one context may not be appropriate in other contexts. For example, in a storage system for serving Internet downloads, high bandwidth and fault tolerance may be priorities, whereas, in a storage system for archiving data records, low cost and low power consumption may be priorities. However, the effects of some trade-offs may not be readily apparent, particularly where a single storage system serves multiple different applications. For example, when storage system resources are allocated to one application, the effect this will have on other applications served by the storage system may not always be readily apparent, even to a skilled designer.
Modeling tools are known for predicting the performance of data storage systems. However, the capabilities of such modeling tools are limited. For example, they do not provide a solution when predicted performance falls short of requirements.
Because specialized skills are required to design and configure a storage system, including assigning storage system resources to applications and verifying that the design meets requirements, such specially-designed storage systems tend to be expensive. Further, due to lack of a systematic approach, the design process can be time consuming and may yield a less-than-optimal result.
Accordingly, it would be desirable to provide a technique for the design and configuration of a data storage system that is more systematic, more likely to yield optimal results and that is less time-consuming than conventional design techniques.

Technique and interface for computer system resource assignment

Hewlett-Packard Development Company, L.P.


The present invention relates to 1,4-disubstituted naphthalene scaffold compounds and other closely related scaffold compounds. The present invention also relates to combinatorial libraries of such compounds. In addition, the present invention relates to a method of identifying a protein-protein interaction antagonist. The method first involves providing a compound as described herein. Next, the compound is contacted with interacting proteins of a protein-protein interaction target complex, whereby the compound is allowed to compete with the interacting proteins. Then, the activity of the compound for inhibiting formation of the protein-protein interaction target complex is measured. Finally, the compound that inhibits formation of the protein-protein interaction target complex is identified as a protein-protein interaction antagonist. Also disclosed is a method for modulating a protein-protein interaction. The method involves contacting interacting proteins of a protein-protein interaction target with a compound as described herein, whereby the protein-protein interaction between the interacting proteins is modulated.

The term "privileged structure" was first introduced by Evans et al. (Evans et al., J. Med. Chem. 31:2235 (1988)). The definition they provided for a privileged structure was "a single molecular framework able to provide ligands for diverse receptors." This concept was partly suggested by the finding that variously derivatized benzodiazepines have been shown to be selective ligands for a variety of proteinaceous receptor surfaces. For example, Evans et al. discovered benzodiazepine analog antagonists of the peptide hormone cholecystokinin (CCK) with binding affinities in the same range as the natural peptide ligand CCK-8 for the peripheral CCK-A receptor (Evans et al., J. Med. Chem. 31:2235 (1988)). Subsequent developments in benzodiazepine and other privileged structures demonstrated that derivatives of these structures can provide potent and selective agonists and antagonists for additional members of the family of G-protein coupled receptors, even though the molecular size of these non-peptide ligands are much smaller than the natural peptide ligands that they mimic (Patchett et al., Annual Reports in Medicinal Chemistry, 35:289, Chap. 26 (2000)). Indeed, following the discovery of benzodiazepine privileged structures, a variety of additional privileged scaffolds (i.e. the substructures upon which the privileged structures are based) have been reported (Horton et al., Chemical Reviews 103(3):893 (2003)). Examples include biphenyl, diphenylmethane, benzopyran (Nicolaou et al., J. Am. Chem. Soc. 122:9939 (2000)), indole, and benzylpiperidine, among others (Horton et al., Chemical Reviews 103(3):893 (2003)). Focused combinatorial libraries based upon these privileged scaffolds have typically provided enriched "hit rates" of receptor agonists/antagonists, ion channels modulators, or enzyme inhibitors, when suitably decorated with appropriate side chains to impart both potency and selectivity.
The privileged structure concept suggests that the intersection of biological diversity space and chemical diversity space tends to occur in particular "nodes" and that privileged scaffolds are positioned within the chemical diversity space of these intersection nodes. This is the underlying concept for "gene-family" screening libraries (e.g. PCT International Publication No. WO 03/19183 to Grootenhuis et al.). From a molecular viewpoint, one can understand this concept in that nature, through the process of divergent evolution, tends to conserve protein molecular features that do not need to be changed and focuses on modifying particular features that are under evolutionary pressure to change in order to take on a new function (Murzin, Current Opinion in Structural Biology 8:380 (1998)). This is a much more efficient evolutionary process than attempting to de novo evolve a new protein for each new needed function. Consequently, one would expect that, within a evolutionarily related gene lineage, there will be certain general structural features within binding cavities that are conserved, whereas the finer details of the topology of these binding cavities will differ to reflect the particular specificities of each individual gene family member. The approximate size and shape of evolutionarily related binding cavities are the properties that would be expected to be conserved, whereas the particular amino acids lining the cavity and the exact position and size of resulting indentations or protrusions in the cavity are the features that would expect to be altered in individual proteins.
With this background in mind, one can envision how privileged scaffolds can be "designed" rather than relying on an empirical discovery, as has typically been the case in the past. The most efficient design approach would be to start with the X-ray or nuclear magnetic resonance (NMR) structure for a representative member of the evolutionarily related proteins. One can then utilize the range of molecular modeling technologies that are currently available to evaluate various candidate scaffolds for their ability to fit in the "middle" of the binding cavity and still allow space for the positioning of various appended side chains for favorable interactions with the amino acids that line the binding cavity. This central positioning of the privileged scaffold also provides a buffer zone around the scaffold, wherein the evolutionarily related proteins can display indentations and protrusions that can interdigitate with the side chains appended to the scaffold without interfering with the ability of the scaffold to bind in the cavity. The presence, nature, and positioning of the appended side chains on these scaffolds will then determine the specificity of the individual compounds due to their ability to interact with the amino acids forming the indentations and protrusions on the cavity surface. One can then synthesize probe libraries around each in silico identified privileged scaffold to determine experimentally which scaffolds are effective.
Designing screening libraries for identifying protein-protein interaction antagonists and, indeed, discovering protein-protein interaction antagonists in general have become a major challenge in drug discovery for the post-genomic era, due to the enormous number of potential untapped drug targets within this category. The ability of proteins to selectively bind to each other forms the foundation of much of biology, including disease biology. Cell architecture, signal transduction, and gene transcription are examples of important cell processes that are at least partly controlled by carefully scripted protein-protein interactions, and are processes that can lead to disease when abnormally altered. Many protein-protein "homodimers" bind very tightly through large, hydrophobic, surfaces, and their monomeric proteins are often unstable due to ready denaturization. In contrast, protein-protein "heterodimers" often bind less tightly, and their contact surfaces are typically more hydrophilic than those of homodimers. Consequently, these proteins tend to be stably folded as monomers and exist in equilibrium with their respective protein complexes. Protein-protein heterodimers are therefore generally considered more amenable targets for small molecule antagonists, because the equilibrium between free monomer and protein complex is more readily disrupted. This equilibrium can be altered by binding to one of the protein partners at the interaction interface, or through an allosteric site. Blocking a heterodimer complex that supports a particular disease biology may not necessarily require that the formation of heterodimer be completely inhibited; rather shifting the equilibrium may be sufficient. Discovering antagonists of protein-protein interactions is widely recognized as much more challenging than discovering enzyme inhibitors or receptor antagonists, even though these drug targets often involve protein substrates or ligands, respectively. The challenges and potential of this field, as well as progress to date, are summarized in several review articles, such as Gadek et al., Biochemical Pharmacology 65:1 (2003), Toogood, J. Med. Chem. 45(8):1543 (2002), and Cochran, Chemistry & Biology 7(4): R85 (2000). Gadek et al. pointed out that " . . . as recently as 5 years ago the existence of small molecule antagonists was controversial. However, the antagonism of protein-protein interactions by small molecules is now well recognized, and the issue focuses on how these antagonists may be efficiently identified" (Gadek et al., Biochemical Pharmacology 65:1 (2003)).
Most protein-protein antagonists have been discovered by random screening rather than by design, and when the generally accepted MW 500 limit for compounds that are likely to be orally active drugs is applied to the reported antagonists, the majority have potencies in the 1-100 μM range (Boger et al., Angew. Chem. Int. Ed. 42:4138 (2003)). The results reported to date demonstrate that obtaining high potency, while maintaining a low molecular weight, is particularly challenging for these drug targets as compared to the more traditional drug targets. The maximum binding affinity possible for a small molecule to a particular protein-protein interaction target will depend upon the nature of the binding interface of the two proteins. Although protein-protein interactions typically involve a large surface area of contact, i.e. greater than 600 Å2, most of the binding affinity is derived from "hot spots" located near the center of the contact surface (Bogan et al., J. Mol. Biol. 280:1 (1998)). In many cases, these hot spots are not deep cavities in the protein surface, in contrast to the deep crevice binding cavities typical for enzyme inhibitors/substrates. A detailed analysis of protein-protein interactions surfaces indicated that the binding affinity attributed to these hot spots is increased by the exclusion of water from this region of the interface by a surrounding hydrophobic "O-ring" of residues (Bogan et al., J. Mol. Biol. 280:1 (1998)). The exclusion of water by the hydrophobic O-ring was proposed to strengthen the interactions in the hot spots by decreasing the dielectric of the microenvironment, thereby strengthening polar interactions, and by reducing the rate of dissociation between hydrophobic groups. Consequently, binding affinity for small molecule protein-protein antagonists may be derived from two factors: 1) the shape and electronic surface complementarity of the small molecule for the hot spot, and 2) the ability of the small molecule to also shield key interactions from bulk solvent. The deeper the binding cavity forming a hot spot the more traditional binding affinity factors will be involved. The more open the binding cavity the more solvent shielding may be important.
The factors described above result in a much higher level of challenge for rationally designing tight binding, low molecular weight, antagonists of protein-protein interactions, as compared to the traditional drug targets.
Experience to date has shown that random high-throughput screening for antagonists of protein-protein interactions has generally been much less successful than has similar screening for other drug targets such as receptor antagonists, enzyme inhibitors or ion channel blockers. This may be due to using screening libraries not suitably biased towards small molecules that have the needed topology for binding to the target protein surface. In order to appreciate the scale of the problem, one needs to recognize that the volume of oral drug-sized chemical diversity space (i.e. MW ca. 500 or less) is enormous. Estimates have put the number of possible compounds with molecular weights of 500 Da or less at 10200 compounds. Even when the typical filters for selecting only drug-sized molecules that are also expected to have drug-like properties (beyond MW) are applied, this number only reduces to 1060 compounds (see Horton et al., Chemical Reviews 103(3):893 (2003)). As Horton et al. points out, "the proportion of these drug-like molecules synthesized to date has been estimated as one part in 1057, or roughly the ratio of the mass of one proton to the mass of the sun" (Horton et al., Chemical Reviews 103(3):893 (2003)). Clearly, there is a pressing need to develop better methods for "targeting" the region of chemical diversity space wherein drug-like antagonists of "drugable" protein-protein interactions reside. It is impossible to cover the total volume of drug-like chemical diversity space with any reasonable density by random broad screening. Toogood, J. Med. Chem. 45(8):1543 (2002) states that "currently, there are no general techniques or approaches that will reliably illuminate the path toward the synthesis of potent and effective drug-like protein-protein binding inhibitors." Toogood then goes on to state "it is hoped that over time some themes may emerge, highlighting for example particular generic structures that may form a basis for protein-protein binding inhibitors. Compound libraries then can be populated with compounds exemplifying these structures, increasing the chances of lead discovery through high throughput screening. Perhaps then the trepidation that protein-protein binding currently imbues in many medicinal chemists will be overcome, and the rich opportunities available for drug discovery finally will be recognized" (Toogood, J. Med. Chem. 45(8):1543 (2002)).
Transcription factor complexes are responsible for much of the regulation of gene expression (Wolgerger, Ann. Rev. Biophys. Biomol. Struct. 28:29 (1999)) and therefore offer many potential protein-protein interaction drug targets (Emery et al., Trends in Pharmacological Sciences, 22:233 (2001)), including anti-cancer targets (Karamouzis et al., Clinical Cancer Research 8:949 (2002)). The 39 members of the HOX family (Scott, Cell. 71:551 (1992)) and 4 members of the PBX family (Knoepfler et al., Mech. Dev. 63:5 (1997)) are proteins that bind DNA as heterodimers to form transcription factor complexes. The numerous heterodimeric HOX/PBX combinations play critical and complex roles in transcriptional regulation during patterning in early embryonic development (Knoepfler et al., Mech. Dev. 63:5 (1997)) and many are utilized again in specific tissues of the adult (van Oostveen et al., Leukemia 13:1675 (1999)). A variety of cancers display altered HOX gene regulation (Maroulakou et al., Anticancer Research 23:2101 (2003)). For example, in leukemias and lung cancers, HOX genes are overexpressed and consequently antagonists of the HOX/PBX complexes controlling these genes offers the potential for novel anticancer drugs. Also, small molecule antagonists of individual (or subsets) HOX/PBX complexes can be used as pharmacological tools to investigation their function.
It would be advantageous to find small molecule antagonists of protein-protein interactions, such as HOX-PBX protein-protein interactions.
The present invention is directed to achieving this objective.

Protein-protein interaction antagonist screening libraries based upon 1,4-disubstituted naphthalenes and related scaffolds

The Research Foundation of State University of New York


A device for optical remote monitoring, preferably an optically readable membrane-based microphone, and a system including such a device is provided. The device for optical remote monitoring includes a retroreflector and an acoustic membrane. The acoustic membrane suitably is a light-modulating component and modulates the reflection of an incident light beam in relation to the pressure field, from a sound source, to which the membrane is exposed. The retroreflector may be a corner cube having three sides with the membrane arranged on one of the sides. The membrane can be part of a side or one side may consist of a membrane.

1. Field of the Invention
The invention relates to a device for optical remote monitoring, preferably an optically readable membrane-based microphone, and a system comprising such a device.
2. Description of the Related Art
It is known to use optical techniques for remote monitoring. Prior-art solutions comprise, inter alia, the laser radar technique for vibration analysis. The laser radar is directed to existing objects in the vicinity of the sound that is to be detected. However, it is difficult to achieve a desirable detection level using current methods. This is partly due to the fact that the intensity of the backscattered light from common surfaces is relatively low. In addition, it is not quite certain that the illuminated surface has a strong connection to the surrounding pressure field.
To avoid these problems, it is known to use an optically readable microphone. The microphone is placed close to the sound source so that it can detect the pressure field. The microphone is illuminated and the reflection is processed in order to recreate the sound. U.S. Pat. No. 5,262,884 discloses, for instance, a microphone comprising a membrane with a lens on one side. The light is directed into the lens and the modulated reflection is registered by a detector. The abstract of JP 2190099 discloses another microphone where a mirror is placed on the membrane to improve the reflection of the laser.
However, these solutions do not always provide very clear results. There is also a risk of disturbances and monitoring.

Device for optical remote monitoring and system comprising such a device


A multi-configurational display rack is disclosed which includes (a) a display rack body having two steps and (b) an angle rack attachable to the display rack body which transforms the display rack body from a two-step configuration to a sloped configuration. The angle rack may be horizontally hingeable into two portions so that, when hinged to an angle of less than 180.degree., the angle rack forms a step, thereby transforming the display rack body into a one-step configuration.. Also disclosed is a display rack having two height-adjustable steps. In one embodiment, the display rack includes (a) a frame member, (b) a first cross member, (c) a second cross member spaced apart from the first cross member, (d) a third cross member spaced apart from the second cross member so that the second cross member is positioned between the first and third cross members, (e) a top step rack component attachable to the first cross member at various heights and to the frame member at various heights, (f) a middle step rack component attachable to the top step rack component at various heights and to the second cross member at various heights, and (g) a flat rack component attachable to the second cross member and restable on the third cross member.

It has long been known to use various types of adjustable display racks in the retail industry, particularly in the grocery industry. Conventional adjustable racks are limited in their ability to adjust for height and depth to accommodate various size display counters and to effectively display varying amounts of merchandise. For example, when less product is to be displayed it is desirable to have a high profile rack in the display counter to achieve a look of fullness for effectively displaying the product. Generally, prior art adjustable shelves have had set height and depth adjustments requiring that the product, rather than the shelf, be rearranged to create an attractive display.
Also, the prior art generally does not provide a rack which is capable of being used in multiple configurations. Generally, conventional racks do not achieve both multiple step and multiple angle configurations with one rack assembly.
It would be advantageous to provide a display rack which is height and depth adjustable. It is desirable to have a single rack assembly which can be placed in multiple configurations including adjustable step and angle positions. Many attempts have been made to produce such a rack, but these attempts have fallen short in meeting the needs of the grocery industry. The following patents exemplify the display racks currently available.
One attempt to produce an adjustable display rack is disclosed in U.S. Pat. No. 4,077,522 issued Mar. 7, 1978 to Trubiano. This patent is for an adjustable display rack which comprises a base frame, a first articulated top shelf supported above the base frame and a second articulated top shelf supported above the first articulated top shelf and collapsible thereon. The first articulated top shelf has a hinge connection at a rear edge thereof. Supports are provided to maintain the articulated top shelves in a predetermined adjustable position above the base frame.
U.S. Pat. No. 3,385,453, issued May 28, 1968 to Dantino et al. discloses an adjustable display rack. The display rack has a first shelf section pivotally connected to the back of a frame. A second shelf section is connected to the first for telescoping and pivoting relative thereto. The first and second sections are mutually supporting to provide a substantially continuous shelf portion when the sections are telescoping. A third shelf section is pivotally connected to the second section and is supported at its forward end on the base. A support depends from one of the second and third shelf sections and is adapted to engage slots on the base for maintaining the shelf sections in different positions. The rack is adapted to fit a display case.
U.S. Pat. No. 3,385,452 issued May 28, 1968 to Dantino et al. teaches a store display rack having a first platform rotatably mounted and a second platform having optional slidable or rotational engagement with the first. The first and second platforms are mounted substantially uniplanar when overlapped and a third platform is rotatably engaged with the second. Support means are provided for maintaining the platforms fixed in relative position when permitting relative movement for varying the position thereof. The platforms can be mounted on a frame adapted to fit into a display rack, which frame can be broken down, or the supplemental bed can be mounted directly on the display rack.
It is apparent, upon review of the above referenced patents, that no single shelf design taught by these references can achieve all the features of the present invention, including height and depth adjustments and multiple step and angle configuration. A display rack, particularly one used in marketing grocery produce, desirably provides one rack capable of merchandising many different kinds of fruit, vegetables and other produce such as cider and fruit juice. The type of fruits and vegetables vary with the seasons, generally soft fruits being available in the summer and harder fruits and vegetables being available in the winter. It is necessary to stack less of the soft fruits to prevent bruising and product loss. Also, it is desirable to have a rack adjustable to a higher or lower profile depending on the amount of product available. When marketing juices or cider, it is advantageous to use many steps to stack the bottles. The width of the step is desirably variable depending on the width of the bottles. It is apparent then that a need exists in the industry for a rack capable of obtaining multiple step and angle configurations and which is height and depth adjustable.
Therefore, it is a primary object of the present invention to provide a multiple configuration display rack including variable step and angle adjustments.
It is yet another object of the present invention to provide a single rack assembly which may be height and depth adjustable to fit display counters of varying sizes.


Performing a snapshot backup includes initiating, by a snapshot driver, a snapshot of at least a portion of a filesystem; and receiving, by the snapshot driver, a filesystem bitmap from a backup agent. Subsequently, the snapshot driver performs copy-on-write operations based on the filesystem bitmap.

The present disclosure relates to data backups, and more specifically, to snapshot backups.
In computer systems, a snapshot is the state of a system at a particular point in time. A full backup of a large data set may take a long time to complete. On multi-tasking or multi-user systems, there may be writes to that data while it is being backed up. This prevents the backup from being atomic and introduces a version skew that may result in data corruption. For example, if a user moves a file into a directory that has already been backed up, then that file would be completely missing on the backup media, since the backup operation had already taken place before the addition of the file. Version skew may also cause corruption with files which change their size or contents underfoot while being read.
One approach to safely backing up live data is to temporarily disable write access to data during the backup, either by stopping the accessing applications or by using a locking API provided by the operating system to enforce exclusive read access. This may be tolerable for low-availability systems such as on desktop computers and small workgroup servers, on which regular downtime is acceptable. High-availability 24/7 systems, however, may not tolerate such service stoppages. To avoid downtime, high-availability systems may instead perform the backup on a snapshot—a read-only copy of the data set frozen at a point in time—and allow applications to continue writing to their data. The time and I/O needed to create the snapshot does not increase with the size of the data set, whereas the same for a direct backup is proportional to the size of the data set.


An electronic product with a standby power source includes a main power circuit for receiving a commercial AC through a power switch and generating a main power source by full-wave rectifying the AC through a diode bridge, and a standby power circuit for receiving the AC and generating the standby power source by full-wave rectifying the AC through another diode bridge, the standby power circuit and the main power circuit being formed on one printed circuit board, and the standby power circuit having an additional ground pattern isolated from a ground pattern of the main power circuit.

1. Field of the Invention
The present invention relates to electronic products with a standby power source, and more particularly, to an electronic product with a standby power source which can reduce power consumption during a standby state.
2. Description of the Related Art
Generally, televisions or video cassette recorders for home use utilize a standby power source as well as a main power source according to a tendency toward multifunction and low power. Therefore, during a standby state, the main power source is turned off, and only the smallest number of circuits, for example, a microprocessor having a timer function and a memory circuit, etc., are driven by the standby power source.
FIG. 1 illustrates the construction of a conventional electronic product with such a standby power source. In a main power source circuit 1, a commercial alternating current (AC) 10 received through a power switch 12 is full-wave rectified through a first diode bridge 14, smoothed to a DC voltage through a smoothing capacitor 16, lowered through a main power transformer 18, and generated as various driving voltages necessary for an operation of a circuit through a rectifier circuit including a diode 20 and a capacitor 22. Meanwhile, in a standby power circuit 3, the commercial AC 10 is full-wave rectified through a second diode bridge 22, smoothed to a DC voltage through a smoothing capacitor 24, lowered through an auxiliary power transformer 26, and generated as a standby voltage, 6.5V for example, through a rectifier circuit including a diode 28 and a capacitor 30.
If two diode bridges are formed on the same printed circuit board 4, a ground pattern is shared. Therefore, during the standby state, although the power switch 12 is in an off state, a main power source is generated during a negative cycle of the AC by forming a current path through the first diode bridge 14, the smoothing capacitor 16, the common ground pattern and the second diode bridge 22. Consequently, unnecessary power is consumed.

Electronic products with standby power source


A polyester resin prepared by polycondensing a dicarboxylic acid component containing terephthalic acid or derivative thereof with a diol component containing ethylene glycol through esterification or transesterification, thereby producing a melt polymerization polymer and subjecting the melt polymerization polymer to solid-phase polycondensation, wherein                (1) the melt polymerization polymer contains comonomer units other than terephthalic acid units and ethylene glycol units in an amount of 5.5 or less, and whose intrinsic viscosity ranges from 0.08 dL/g to 0.50 dL/g and which has an apparent crystallite size smaller than 9 nm, and wherein        (2) the melt polymerization polymer is subjected to solid-phase polycondensation at a temperature which is higher by at least 140° C. than the glass transition temperature of the melt polymerization polymer and is not higher than the melting point of the polymer to thereby obtain a polyester resin having an apparent crystallite size smaller than 9 nm.

Polyester resins, in particular poly(ethylene terephthalate) (hereinafter sometimes abbreviated as PET), which is produced from terephthalic acid and ethylene glycol as raw materials, are extensively used as many materials and products such as, e.g., fibers, textiles, molding resins, and beverage bottles.
In order for a polyester resin to have the moldability and mechanical properties which are necessary for those applications, it should have a degree of polymerization increased to a given level. A method in wide industrial use for this purpose comprises subjecting raw materials for a polyester to melt polycondensation to obtain a polycondensation product having a relatively high viscosity and subsequently subjecting the polycondensation product to solid-phase polycondensation. However, the solid-phase polycondensation in this method heretofore in use necessitates a relatively long time period. There is hence a desire for a production process attaining better productivity.
A process for polyester resin production has been proposed as a process with improved productivity. This process comprises subjecting raw material monomers for a polyester to melt polycondensation to obtain a melt polymerization polymer having a relatively low degree of polymerization and subjecting this melt polymerization polymer to solid-phase polycondensation. For example, JP-T-10-512608 (WO 96/22319) discloses a process in which a lowly polymerized melt polymerization polymer obtained by melt polycondensation and having an average degree of polymerization of from about 5 to about 35 (intrinsic viscosity of about from 0.10 to 0.36dL/g) is crystallized so as to result in a crystallite size of 9 nm or larger and then subjected to solid-phase polycondensation. (The term "JP-T" as used herein means a published Japanese translation of a PCT patent application.) There is a statement therein to the effect that according to this process, polycondensation can be initiated at a higher temperature, e.g., 230° C., preferably at 240° C., to directly obtain the target polymer. However, our investigations have revealed that a satisfactory rate of solid-phase polycondensation is not always obtained possibly because the degree of polymerization at the time when the solid-phase polycondensation is initiated is too low or because crystals grow to inhibit the movement of molecules, although the reasons are unclear.
On the other hand, U.S. Pat. No. 6,284,866 discloses a process for producing a copolyester for use as bottles reduced haze in low-temperature. In this process, a melt polymerization polymer which is a polyester in which the sum of a dicarboxylic acid component copolymerized (mol %) and a diol component copolymerized (mol %) is 6 or more and which has an intrinsic viscosity of from 0.25 to 0.40 dL/g is subjected to solid-phase polycondensation under specific conditions. However, the process disclosed in that patent document is not always industrially advantageous because the solid-phase polycondensation is conducted with a rotary-vacumn tumble dryer and is solid-phase polycondensation under high vacuum. Furthermore, our investigations revealed that the melt polymerization polymer has a relatively low melting point because of the too high proportion of comonomer units and, hence, a high temperature cannot be used for the solid-phase polycondensation when it is not conducted under high vacuum. Consequently, the rate of solid-phase polycondensation is low and the process is not efficient when it is not conducted under high vacuum.
An object of the invention is to provide a process in which the solid-phase polycondensation of a polyester is conducted at an exceedingly high rate and a polyester is hence produced with satisfactory productivity. Another object of the invention is to provide a process in which the solid-phase polycondensation of a polyester can be carried out at a high rate without the necessity of using special conditions, e.g., high vacuum, and a polyester is produced with satisfactory productivity without posing any problem concerning handling, such as, e.g., the fusion bonding of the resultant polyester resin to itself or the adhesion of the polyester resin to the reactor.


In a method of determining a beam to be generated for a user, a user may be selected from a user population based on a parameter that is tracked for each user in the user population, and a beam preferred by the selected user may be determined. The preferred beam may be generated and used by a base station to transmit a pilot signal to the user population. Each user of the user population responds to the pilot signal. The base station may run a scheduling algorithm and schedule a user based on feedback received from all the users in the user population, and information may be transmitted to the scheduled user using the preferred beam.

1. Field of the Invention
The present invention relates to beam generation and scheduling of users in a communication system.
2. Description of Related Art
Opportunistic scheduling (OS) has been proposed as a scheduling technique to improve the downlink throughput of high speed packet systems. OS (as employed in a base station scheduler or scheduling algorithm, for example) exploits the fact that the propagation channels between the base station and the MSs served by the base station fade independently. This independent fading gives rise to what is referred to as multi-user diversity (MUD). Multi-user diversity is a form of diversity that schedules transmissions to users, when their time varying channels approach their top capacity, thus increasing the throughput of the system.
OS exploits the fact that many data services are delay tolerant. However, real time services such as voice, and in some cases video, can accept only a limited amount of packet delay, thus a scheduler should also consider packet delay statistics. Additionally, the issue of fairness should be addressed. Accordingly, a scheduler or scheduling algorithm implementing OS should weigh desired system throughput with fairness and delay statistic considerations.
Several schedulers or scheduling algorithms have been developed in an effort to provide reasonable tradeoffs between throughput, delay statistics and fairness. A scheduler known as a proportional fair (PF) scheduler has been developed to provide improved throughput and fairness over the downlink of the High Data Rate (HDR) standard. It has been shown that the PF scheduler maximizes the sum of the logarithms of the MS's average throughput. In another scheduler, a fraction of timeslots allocated to each user can be arbitrarily chosen based on desired objectives (such as meeting desired Quality of Service (QoS) requirements), and the scheduler then maximizes the average system throughput under the time allocation constraints. A further scheduling algorithm, known as a Modified Largest Weighted Delay First algorithm, supports n MSs with desired Quality of Service (QoS) based on the expression: Pr{Wi>τi}≦δi, i=1, . . . ,n. In the above expression Wi is the packet delay for MS i, τi represents a delay threshold, and δi represents the maximum probability of exceeding the delay threshold, respectively.
Each of the above exemplify schedulers or scheduling algorithms employ OS techniques. However, when the coherence time of the propagation channels is long in comparison with an acceptable packet delay, or when the fading is weak (e.g., Ricean fading with high K factor), OS is not useful.
Accordingly, to address the slow channel or weak fading scenarios, a scheduling technique know as Opportunistic Beamforming (OBF) has been proposed. OBF is a "natural" enhancement to OS that, in general, amounts to replacing a base station having a single antenna with multiple antennas and implementing an algorithm that generates a different radiation pattern, henceforth referred to as a 'beam', every timeslot. The sequence of beams may be completely random and a-periodic, or could be chosen pseudo-randomly, from a fixed pre-designed collection of N beams. OBF techniques may be distinguished from other proposed downlink beamforming systems by the simplicity of the techniques. For example, and similar to OS, OBF requires a small amount of uplink feedback, while the beam generating algorithm runs independently, i.e., does not receive any information from the rest of the system.
Communication systems employing OBF techniques have been considered in two different environments, an uncorrelated environment and a correlated environment. In an uncorrelated environment, propagation channels between a MS and any of the BS's antennas are all uncorrelated. A realistic system comes close to this case when the antennas of each BS are placed sufficiently apart (e.g., 10 feet at 2 GHz) and there is some scattering in the environment. In a correlated environment, the propagation channels between any MS and all the antennas of a single BS are highly correlated, but channels to different BSs are uncorrelated. A realistic system comes close to this case when the BS's antennas are placed close to each other, (e.g., one half wavelength apart), and the angle spread at the BS is low. As it has been shown that, in general, a correlated system outperforms an uncorrelated system, the correlated system is therefore of focus herein.
In currently developed OBF techniques, high throughput and good delay properties are conflicting objectives. Studies on OBF techniques have primarily focused on the scheduling algorithm alone, while the beam generating algorithm for a correlated system was taken to be a simple periodic scanning of the desired cell/sector. The beam generating algorithm was running independently from the scheduler, and no attempt has been made to use system state information to modify the beam sequence in any way. A joint study on beamforming and scheduling has not heretofore believed to have been conducted.

Opportunistic beamforming and scheduling of users in a communication system


To maintain and manage a computer network, a system administrator may monitor a large number and variety of components, each component comprising a variety of resources. The instrumentation of a resource may be monitored and/or manipulated by receiving a Simple Object Accessing Protocol (SOAP) message comprising an operation identifier for accessing instrumentation information and a resource identifier associated with a computer system resource. The management system may resolve the resource identifier into an address for a local handler associated with the resource, and may send a local request to the local handler at the resolved address.

Distributed and networked computer systems typically comprise a variety of types and sizes of components such as routers, gateways, servers, databases, personal computers, and the like. Each component may include a variety of resources including hardware and software resources such as disk drives, fans, memory allocation, and the like. To manage and maintain the effective use of these components, a systems administrator may monitor the health and other computer system management information of the resource, and modify that information if necessary or otherwise take corrective action. To monitor the system information, the systems administrator may communicate with the desired resource either receiving broadcast messages of status and health information and/or requesting specific information from a defined port. The format of the messages containing the health and/or status information may be controlled by one of several standard protocols which define the format of messages presenting status information from certain devices. For example, Simple Network Management Protocol (SNMP) is a Transmission Control Protocol/Internet Protocol (TCP/IP) standard that is used to manage and control IP gateways and the networks to which they are attached. In another example, SYSLOG is a distributed interface standard for logging short text messages regarding systems health information which are communicated to clients with User Datagram Protocol (UDP) datagrams. In yet anther example, Intelligent Platform Management Interface (IPMI) is a remote management control protocol (RMCP) for request/reply and uses SNMP for events/traps. IPMI is further IPMI data and SNMP data can be mapped into the common information model/Web-based enterprise management (CIM/WBEM)-based standards for retrieving and describing management data over HTTP. In another example, Web Services Distributed Management (WSDM) is a management standard directed toward Web-services.

Computer system for accessing instrumentation information


The invention discloses a radio frequency front-end based on the high-intermediate frequency superheterodyne and zero intermediate frequency structure, which includes a transmitting module and a receiving module, wherein, the receiving module includes the following devices connected in turn with each other: a transceiving antenna, a low-pass filter, a superheterodyne unit, an IF band-pass filter, a zero-IF unit, a analog-to-digital converter and a digital baseband module of which the output is communicated with the transmitting module. The zero-IF unit includes the following devices which are also connected in turn with each other: a zero-IF mixer, an active low-pass filter and a variable gain operational amplifier of which the output is communicated with the input of the ADC; the inputs of the zero-IF mixer are communicated with the output of the IF band-pass filter and the second LO respectively. The present invention avoids the image interference, improves the system integration and decreases the system consumption.

Among the numerous wireless access systems, the core element of the communication facilities is the RF front-end chip. The RF front-end is mainly used for amplifying, frequency converting, filtering and quantizing the weak signal received from the antenna of the receiver, and demodulating it to the baseband signal. Thus, design of the RF front-end circuit shows significant importance to the design of the whole receiver and has direct influence on the performance of the wireless receiving device.
A conventional RF front-end of a communication terminal is structurally constructed of: superheterodyne structure, zero intermediate frequency (IF) structure, double-conversion wide IF structure, double-conversion low IF structure, and the like. Wherein, the superheterodyne structure, due to its optimal sensibility, high selectivity and large dynamic range, is considered to be the most reliable topological structure of receiver and the preferred high-performance receiver. The typical superheterodyne structure, as shown in FIG. 1, employs mixer for converting the HF signal to a lower IF and then going through the channel filtering, amplifying and demodulating, to effectively overcome the problems when dealing with the HF signal. However, an IF filter with high-quality factor is necessity of filtering the image interference effectively, which is unrealizable in the existing CMOS process. Furthermore, as shown in FIG. 2, the IF of the superheterodyne structure is normally lower than the frequency of the RF signal, which leads to the existence of a fatal defect of image interference for the receiver. The superheterodyne structure is commonly applied to the RF front-end of the narrow-band communication system, when applied in the broad-band, such as receiving the 900 MHz RF signal in the 100 MHz to 1.2 GHz range with the superheterodyne structure, providing the IF frequency is of 13.56 MHz. In fact, the receiver receives not only the useful signal at 900 MHz, but also the image interference at 927.12 MHz. The image interference frequency of the RF front-end of the conventional superheterodyne structure totally falls in a narrow range around the useful channel, which has the defects of difficulty in distinguishing the two kinds of signals. The structure has a low sensitivity and is hard to integrate. Besides, when introducing the superheterodyne structure in the broad-band communication, the first local oscillator (LO) is strictly demanded. In the above-mentioned example, the tuning range of the frequency synthesizer is from 113.56 MHz to 1213.56 MHz, which has a lower center frequency and a tuning ratio of 85%.

Radio frequency front-end based on high-intermediate frequency superheterodyne and zero intermediate frequency structure


A first storage unit is a storage area for storing original images. Inputted to an input unit is an operation instruction from a user. An obtaining identifying unit identifies an optimal original image pair. An obtaining processing unit accesses the first storage unit to obtain the optimal original image pair. A converting unit converts scales of respective images included in the optimal original image pair into a designated scale to generate intermediate images. A corresponding point matching unit makes the corresponding areas of the intermediate images coincide. A combining unit combines the intermediate images using a predetermined ratio to generate a target image. The resultant target image is outputted from an output unit to a monitor.

1. Field of the Invention
The present invention relates to an image generating technique and, more particularly, to an image generating method and image generating apparatus operated on the basis of combining a plurality of images.
2. Description of the Related Art
Techniques for displaying a digitized map image on a display apparatus have been known in the form of software for PCs or Internet services. Map images are generally prepared for a plurality of discrete scales so that one of the plurality of map images is displayed at a desired point of time.
When a scale is changed and a map image displayed on a display apparatus is changed accordingly, a user may lose sight of an object that the user had paid attention to or it may take a substantial time for the user to understand the currently displayed area. From these points of view, when the scale of a map image is changed, the displayed map image is desirably switched from one to another smoothly.
Smooth switching between displayed images is required not only in the case of digitized map images but also in the case of drawing a landscape in applications such as games. In games, three-dimensional data of objects are prepared in advance. An image is re-rendered in accordance with a change in the magnification of image to be displayed and the position of point of view, so that smooth image changing or switching can be realized. The volume of calculation required for the re-rendering may be significantly increased depending on the degree of movement of point of view, the number of objects to be displayed and the degree of complexity thereof. Further, there may arise a problem about the size of capacity of memory for storing three-dimensional data of a large number of objects. Accordingly, for CG images in general, including those used for games, smooth changing between images requires further technical improvement.

Image generating method and image generating apparatus


A system and process is provided for cladding the interior of plasticating barrels or any other interior surface. The cladding operation uses a laser head that carries out a spiral welding operation to create a smoother lining than is capable with conventional welding techniques. A number of different techniques can be used, including the use of feeding laser energy at one end of a tube to be reflected from laser aiming optics inserted through a second end of the tube. Unidirectional welding can be used to facilitate gravity as a smoothing agent. In another embodiment omnidirectional welding can be carried out using a shaped mirror and a donut-shaped laser pattern. The cladding operation can be simplified by baking a coating of the welding matrix and anti-abrasive material onto the interior of the surface to be clad prior to the welding operation.

The present invention relates generally to the field of plasticating components, such as screws and barrels, used for extruding plastic. In particular, the present invention is directed to a structure for a more abrasion-resistant and corrosion-resistant plasticating barrel, and a technique for manufacturing the lining of the improved barrel.
Extruders and tubers (rubber extruders) have been in use at least since the beginning of the twentieth century. With the advent of plastics, the demand for such extruders has become greater and the processing conditions have become more severe. Originally such devices were essentially a simple screw rotating inside a single-material barrel without a lining. This is no longer the case due to the newer and more difficult to process materials.
Both of these components are subject to wear from metal-to- metal contact, and from abrasive and corrosive fillers in the plastic or rubber compounds. The original barrels had an internal surface that was nitrided to give improved abrasive wear resistance. In the later 1950""s bimetallic barrels were developed using a centrifugal casting process, as briefly described in the Spirex publication, entitled Plasticating Components Technology, 1997, incorporated herein by reference. Also, such improved barrels were adapted for use with injection molding machines, in addition to conventional extruders.
Centrifugal casting of plasticating barrels is a process used to line the internal surface of a barrel with an abrasion and/or corrosion resistant liner that is different from the barrel backing material or substrate. The process involves installing a lining material, such as a powder, inside the heavy-walled barrel cylinder at room temperature. The ends of the barrel are capped (usually welded) and the barrel and unmelted powder are placed in a casting oven. The barrel is then rotated and heated until the liner material metals are melted uniformly distributed on the internal surface of the barrel. Early liner materials were iron/boron materials that created some metal carbides and were very much more wear resistant that the nitrited barrels. In 1968 improved liners became more abrasion resistant by the addition of very small, discrete metal carbides particles like tungsten carbide and equivalent materials.
Most rotational casting ovens are gas heated but some are induction heated. In either case, the inside of the barrel must be heated to a point where the liner powder melts, but the thick-walled barrel material or substrate does not melt. After melting is accomplished the barrel is slowly cooled so that stresses are not induced, and so that the liner material does not crack. After cooling, the barrel is honed, straightened and machined to it""s final dimensions. Often this requires installation of a high-pressure sleeve at the discharge end of the barrel.
There are a number of disadvantages to this technique. The gas fired or induction furnaces with rotating equipment are very expensive, and require extensive maintenance. This includes periodic and prolonged shutdowns to reline the refractory surfaces of the oven. Further, even when the furnaces are functioning properly, set up for the coating of each barrel is an awkward and time, consuming process.
Also, the process of centrifugal coating requires that the liner material or material matrix melt at a lower temperature than the backing or substrate material. This creates severe limitations on the liner materials than can be used. As a result, abrasion-resistant and corrosion-resistant materials are limited to formulas that melt at a lower temperature than the barrel substrate. In many cases the optimum barrel substrate and under materials cannot be used for the materials to be handled.
There is also the requirement of raising the backing or substrate material to a temperature close to the melting point of the substrate material followed by a slow cooling to anneal the backing material. This lowers the strength of the annealed backing material. Unfortunately, very high strengths are now required because such barrels can be subject to internal pressures of 40,000 psi or higher, and temperatures up to 700 deg. F. These conditions require the installation of a high pressure sleeve at considerable expense. Some newer, higher priced alloys can reduce this effect somewhat by reducing the loss of strength. However, greater expense is incurred.
During the rotational casting process the heavier metal carbide particles tend to be thrown outward by centrifugal force. This moves these particles away from the inside surface where they are needed for abrasion resistance. As a result, the resulting lining is far more susceptible to wear caused by abrasion than if the metal carbide particles are properly located on the inner surface of the lining or evenly distributed throughout the lining or cladding.
The high barrel temperatures that are reached during casting make it difficult to maintain the straightness which is critical to the plastic processing operation. Straightening of the barrel cannot be done by conventional straightening presses because reverse bending cracks the relatively brittle liner. The rotational casting process requires a long time to heat up the liner and barrel substrate. Additional time is required for slow cooling after the lining operation. This causes added expense in labor and electrical costs.
Because the lining process can only be successful in a very narrow range of time and temperatures, often the results are not satisfactory. High temperatures and long time periods spent at these temperatures cause dilution by migration of the substrate material into the barrel lining material. This causes poor hardness and poor abrasion resistance. Also substrate migration of the base iron material can cause poor corrosion resistance in certain applications. Extended periods at high temperatures also cause the metal carbide particles coating the liner inner surface to melt into solution in the matrix matter (constituting the liner) rendering them useless.
When temperatures are too low and the time periods at properly elevated temperatures are too short, an inadequate metallic bond can result. Such an inadequate metallic bond means that the liner may become separated from the barrel substrate or backing material. This condition could render the entire barrel useless. Further, in some cases portions of the liner may come dislodged, corrupting the molten plastic and/or fouling the screw pushing the molten plastic through the barrel. In either case, the barrel is subject to catastrophic failure, and the plastic processed therein ruined.
A totally different method to produce barrel liners is constituted by laser welding or cladding. Laser cladding is laser welding of a different surface onto a base or substrate metal. This new process diminishes or eliminates all of the disadvantages listed above.
The more conventional MIG or TIG welding of the inside diameter (ID) of barrels can be done, but it is more difficult to get into smaller diameter barrels. The zone affected by heat is much greater, and the welded surface is poorer, causing much greater expense in finishing compared to the xe2x80x9cnear-net shapexe2x80x9d of laser-welding.
Laser welding of the ID of barrels involves the depositing of the liner material prior to welding in the form of paste or a separate liner tube, or during welding with a powder or continuous wire. The laser welder usually includes a laser beam delivered from a remote source via fiber optics and optical systems, or by direct laser beams.
This technique has a number of advantages. For example, devices have been made that will allow laser welding into diameters as small as xc2xe inch. Laser cladding also has a very shallow heat-affected depth which gives much less dilution of the liner material into the barrel substrate. This technique also creates much less stress in the substrate, reducing the tendency to bend or warp.
Laser cladding is a relatively robust process that allows a wide latitude of materials to be used, including materials that melt at higher temperatures than the barrel substrate. This can lead to improved matrix materials and improved ceramic or carbide materials as anti-abrasive coatings on the liner. Discrete abrasion resistant carbide or ceramic particles do not migrate toward the substrate as in rotational casting. This leaves them evenly distributed where they are needed.
The substrate does not necessarily need to be preheated prior to welding, thus reducing production time and expense. Heat imparted by the laser welding process is much reduced and can be removed during welding by internal and external methods. This means that a long cooling down time can be eliminated. As a result, the process is less time-consuming than centrifugal casting.
Laser welding is an actual welding process with a metallurgical bond rather than a brazing process where the liner melts at a lower temperature than the substrate as in rotational casting. The laser cladding equipment is generally lower cost than gas-fired or induction furnaces.
Several devices to laser clad the inside of pipes have been invented and commercialized. These include EPRI Patent Nos. 5,653,897 and 5,656,185 and IHI Patent No. 5,426,278. Also included are U.S. Pat. Nos. 5,496,422; 5,196,272; and, 5,387,292. All of the aforementioned patents are incorporated herein by reference to facilitate a better understanding of the present invention. These devices are designed to repair damaged or corroded heat exchanger tubes in power generation plants. These systems are designed to make short, localized repairs in relatively long, fixed pipes that cannot rotate. Consequently, each of these systems uses a rotating laser head for welding. The systems described in the aforementioned patents include the insertion of a cladding or inlay material by wire, powder, paste, and thin wall tube. The paste and the tubes are already in place before laser cladding. In the case of the EPRI patent, a coiled wire is placed inside the pipe directly above the repair area in order to have it easily accessible and easy to feed as the cladding proceeds. This method is limited to short longitudinal lengths of welds as is generally required in boiler repair. Powder is difficult to introduce in the horizontal position because, without gravity assist, it tends to clog and interrupts cladding. Drawings of these various welding devices are shown in the patents.
For prolonged or full length cladding of 20:1 L/D or longer pipes the head and especially the reflecting mirrors must be cooled. This can be done by a cooling fluid such as air or water. The EPRI patent does not have such cooling except for the bearings that are required to rotate the head inside the pipe. The IHI device allows cooling (by air) coming from the direction of the laser source.
All of these devices must have all auxiliary services introduced from the laser head end of the tube because access from the opposite end is not available, and cannot be coordinated with the activity provided from the laser end. These auxiliary services can include fiber optical viewer, wire/powder feeds, cooling media, optics (lenses) and focusing devices.
The devices disclosed in the subject patents weld on constantly changing surfaces. This tends to give a non-uniform and less smooth surface due to the influence of gravity. If the cladding is done with the pipe vertical, the melt pool tends to not be flattened and can have exaggerated rings or other distortions in the surface. In any case, there is no natural tendency to flatten and smooth the surface in a uniform manner.
Also materials currently used in conventional laser welding processes are used primarily for corrosion resistance. This limited application of the conventional technology is adequate since the boiler tubes (in which conventional laser welding occurs) are not exposed to the abrasion of the types of materials handled by plasticating barrels.
There is also a need to make such devices smaller than the standard commercial sizes now available. In particular, barrel I.D.""s as small as 14 mm (0.551 inch) are used for plasticating barrels. Thus, appropriate welding devices are necessary to clad or line the interior of the plasticating barrels. Conventional rotating welding devices operate entirely from one end of the tube being lined or welded. Consequently, size reduction for such welding devices is severely limited. This is particularly true since the welding head must include all auxiliary services, as well as the bearings. This entire structure is fed into the tube to be welded from only one side of the tube. As a result, size reduction of the overall welding apparatus is very problematical, and cannot accommodate some smaller sizes used for plasticating barrels.
Accordingly, there is a need for a system capable of addressing the smaller sizes of plasticating barrels, and to provide smooth, uniform inner linings to such plasticating barrels. Of necessity, such a system will have to be flexible, and capable of using a number of different techniques to produce an optimum product at reasonable costs.
It is one object of the present invention to provide a system for lining tubes or any interior surface that overcomes the drawbacks of the conventional art.
It is another object of the present invention to provide a system for inside diameters (I.D.) that is sufficiently flexible so that a wide variety of tube sizes and cladding materials can be accommodated.
It is a further object of the present invention to provide a system for lining inside diameters of tubes capable of accommodating smaller I.D. sizes than is currently possible with conventional techniques and systems.
It is an additional object of the present invention to provide a system for lining inside diameters of tubes in which a more uniform lining can be achieved than is possible with existing welding techniques.
It is again a further object of the present invention to provide a system for lining of I.D.""s in which a smoothing agent operates in a uniform manner on each of the welds constituting the cladding of the plasticating barrel.
It is still another object of the present invention to provide a system for laser-cladding the interior of a metal tube wherein the system is relatively simple to set up compared to conventional systems.
It is again a further object of the present invention to provide a process for laser-cladding the interior of a metal tube, requiring reduced operating time.
It is still another object of the present invention to provide a system for quickly and easily repairing the lining of metal tubes at lower expenditures than those incurred with conventional systems.
It is again a further object of the present invention to provide a system for lining the interior of the metal tube by laser-welding wherein the conventional necessity of a rotating laser head is avoided.
It is yet another object of the present invention to provide a system for lining a metal tube using laser welding in which movement of the welding head is required only along the axis of the tube being welded.
It is again a further object of the present invention to line a metal tube using laser welding to which an anti-abrasive material is added so that the anti-abrasive material remains uniformly distributed in the laser-welded cladding.
It is yet another object of the present invention to provide a smoother, pre-machined weld that is obtainable from conventional welding techniques, in particular, MIG and TIG methods.
It is yet another object of the present invention to provide a method of uniformly precoating an accurate amount of material on an interior surface to facilitate welding operations thereon.
It is still a further object of the present invention to provide a system of precisely placing a uniform pattern of anti-abrasive material in a weld melt without melting or otherwise degrading the anti-abrasive material.
It is yet another object of the present invention to facilitate faster, pre-weld set up of plasticating barrels.
These and other goals and objects of the present invention are achieved by a plasticating barrel adapted for use with extruded molten plastic. The barrel includes a substrate composed of a first metallic material and a liner composed of a second metallic material. The liner is fabricated by laser welding to achieve a substantially uniform cladding over the entire diameter of the barrel. The liner is formed to have an inside diameter of less than 15 mm as finished by laser welding.
In another embodiment of the present invention, a plasticating barrel is adapted for use in extruding molten plastic, and includes a substrate of a first metallic material and a liner of a second metallic material. The liner is formed by laser welding of the second metallic matrix material to clad the interior of the barrel. An anti-abrasive layer is formed of a third material composition and is uniformly arranged in unmelted form throughout the metallic matrix.
Another embodiment is constituted by a system for laser-welding a lining to the interior of a metal tube. The system includes a laser welding head arranged to enter the metal tube from a first end of the metal tube. The system also includes auxiliary equipment arranged to enter the metal tube from the second end of that metal tube.
In yet an additional embodiment of the present invention, a system for lining a metal tube by laser-weld cladding is provided to include a laser aiming optic head. Also included is a device for holding the metal tube in a horizontal position and rotating the tube about a horizontal axis. Another device is used to position the laser aiming optic head so that welding always takes place in a single direction. A controller coordinates the rotational movement of the metal tube and the operation of the laser aiming optic head.
It is still a further embodiment of the present invention a system is provided for lining an interior surface. The system includes a laser aiming optics head and a mechanism for welding/cladding on the bottom surfaces thereby applying gravity to create a series of smooth uniform welds that constitute the lining of the metal tube.
Yet another embodiment of the present invention includes a system for lining a metal tube by laser-welding. The system includes a laser source arranged to emit laser light into a first end of the metal tube. The system also includes a laser aiming optics head arranged to deflect light from the laser source, and arranged to enter the metal tube at a second end.
Yet an additional aspect of the present invention includes a system for lining a metal tube by laser welding. The system includes a laser aiming optics head arranged to deflect laser light entering the metal tube at the first end of the metal tube. The laser aiming optics head is rotateably mounted an arranged to enter the metal tube at a second end of the metal tube.
Another aspect of the present invention is manifested by a method of lining a metal tube by laser welding. The process includes the step of arranging the metal tube in a horizontal position. Next a laser aiming optics head is placed in the metal tube. Then a series of laser welds are carried out in a single direction while rotating the metal tube and moving the laser aiming optics head in a single direction along the metal tube.
Again another aspect of the present invention is a method of lining a metal tube by laser-welding, where the method includes the steps of placing a laser aiming optics head in the metal tube at a first end of that tube. Then, laser light is transmitted from a second end of the metal tube to be deflected by the laser aiming optics head to effect laser welding in the metal tube.
Yet an additional aspect of the present invention is a method of cladding an interior surface by laser welding. The method includes the first step of arranging a laser aiming optics head to operate in a predetermined pattern along the interior surface to create a series of weld melts. Each of the weld melts has a warmer heating portion and a cooler trailing portion. Then, an anti-abrasive material is added to the trailing portion of each of the weld melts. As a result the anti-abrasive material is undegraded and uniformly distributed through each of the weld melts.
An additional aspect of the present invention is manifested by a plasticating barrel adapted for use of extruding molten plastic. The barrel is of a first metallic material, and is provided with a laser clad lining of a second metallic material. The second material is a mixture of nickel and chromium.
Still an additional aspect of the present invention is a method of lining a tube including a first step of inserting a slurry into the tube. A slurry includes liner material. Then the tube is centrifugally cast to form a uniform hard coating of the slurry to adhere to the inside diameter of the tube. Then laser welding is carried out on the coating to form the finished metallic lining.

Method and laser cladding of plasticating barrels