Decoding using miscorrection detection is disclosed. A measure indicative of the number of proposed corrections included in a set of proposed corrections corresponding to one or more of a plurality of read values is received. The plurality of read values corresponds to a codeword. It is determined whether the number of proposed corrections is a permitted number of corrections.

During decoding of error correction codes such as BCH codes, Reed-Solomon codes, and Hamming codes, a decoder will typically report a received sequence to be correctable or uncorrectable. However, miscorrection can occur when a decoder claims the received sequence to be correctable to a particular codeword, but the codeword is different from the actual transmitted codeword.

Decoding of turbo product codes using miscorrection detection


A tolerance input/output circuit is provided for operating as the interface of a device to which a predetermined voltage or more cannot be applied to make it operate, depending on whether it is in an input mode or an output mode. The circuit includes an internal power supply, a Y gate signal generator, a kilpoly signal generator, a P gate signal generator and an output circuit. The Y gate signal generator receives an external pad signal of a high level, then generates a signal of an internal power supply level. The kilpoly signal generator generates the signal of the internal power supply level when the pad signal is at a low level, and generates the pad signal when the pad signal is at a high level. In an input mode, the P gate signal generator generates as a P gate signal the signal of the internal power supply level, when the pad signal is at a low level, and the pad signal, when the pad signal is of a high level. In the output mode, the P gate signal generator generates as a P gate signal the internal power supply level when the pad signal is at a low level, and a signal of a low level when the pad signal is at a high level. The output circuit generates a signal which has a high impedance in the input mode and which normally operates to supply the internal power supply level of a high level in the output mode, as the pad signal. The output of the kilpoly signal generator is fed back to the substrates of the PMOS transistors included in the kilpoly signal generator, the P gate signal generator and the output circuit.

1. Field of the Invention
The present invention relates to a tolerance input/output circuit, and more specifically, to a tolerance input/output circuit operating from a single power supply.
2. Description of the Related Art
FIG. 1 is a circuit diagram of a conventional tolerance input/output circuit. The circuit includes five blocks 10, 20, 30, 40 and 50.
Block 10 generates a correction signal 102, at a level appropriate to the characteristics of a given device, to a Y gate `Y` and to one of the input terminals of block 20. This correction signal 102 is derived from pad signal 101 which is applied to a PAD and passed through a resistor.
Block 20 receives the correction signal 102 and an enable signal 201, generating an inverted correction signal 102b and an inverted enable signal 201b.
Block 30 generates a P gate signal 301 depending on whether the circuit is in an input or output mode. Block 30 receives the inverted correction signal 102b, the inverted enable signal 201b and the pad signal 101.
Block 40 is for generating a kilpoly signal 401. It receives the pad signal 101 and the inverted correction signal 102b.
Block 50 receives N gate signal 501 and P gate signal 301, generating a pad signal 502 depending on whether it is in an input or output mode. This pad signal 502 is fed back as the pad signal 101.
FIGS. 2 and 3 show voltage and current characteristics when the pad input voltage is swung from 0V to 5.5V, in the conventional tolerance input/output circuit of FIG. 1. As shown in FIGS. 2 and 3, when the pad voltage is swung to 5.5V, forward-biased diode formed on each source region. The bulk of PMOS transistors included in Block 40 reduces the response speed of the voltage characteristics of the kilpoly signal 401 and generates much leakage current in the substrate.

Tolerance input/output circuit operating in single power supply


A container for audio compact discs, CD-ROMs and other similarly-shaped articles having central holes used to secure the article therein and facilitate easy removal of the article therefrom. Multiple embodiments include a container having a disc-supporting base and a disc-enclosing lid, pivotally attached to each other. One end of a protruding member is pivotally attached to the base. The other end of the protruding member is free to rotate and is inserted through the central hole of the disc to be stored in the container. When the container is closed, one distinct section of the protruding member contacts the upper surface of the disc and another distinct section of the protruding member contacts the lower surface of the disc to support it and secure it in the container. Upon opening the container, vertical displacement of the protruding member automatically lifts the disc upwards off of the base, allowing easy access to the disc.

1. Field of the Invention
The present invention relates to containers for audio compact discs, CD-ROMs and other similarly-shaped articles having central holes, and more specifically to containers that secure the article therein and facilitate easy removal of the article therefrom.
2. Description of the Related Art
With the recent technological advances and the increased popularity and availability of disc-formatted information media, various devices for disc storage and protection have been developed. Folding containers fabricated of plastic, paper, or other materials have provided means to enclose the disc, thereby protecting it from damage and allowing it to be stored in an easily retrievable and secure fashion.
One type of container comprises flat, multifaceted sheets of material which are folded in an envelope-like configuration to store and protect the disc. Examples of this include U.S. Pat. No. 5,248,032 and British Patent Application No. 2,272,887 A. Another disc storage mechanism, illustrated by U.S. Pat. Nos. 5,284,242 and 5,377,827, incorporates upper and lower components that are connected with a hinge along one side, which operates to open and close the disc container. Protrusions on the interior container surface, often in the form of a circular hub, comprise an anchoring means for insertion into the disc's central hole, affording a further way of securing the stored disc. Unfortunately, manual removal of the disc from the hub requires considerable effort on the part of the user, often making disc retrieval difficult. In addition, an excessively forceful manual extraction from the hub increases the risk of damage to the disc in the event it was accidentally dropped, deformed or otherwise mishandled. In these respects, the hub storage system is inadequate.
Attempts to alleviate these problems have resulted in improvements in the art of disc containers. While retaining the hub component, disc containers designed to avoid removal-related problems featured ways for the disc to be lifted from the hub and placed on its top surface. In this way, the disc would not require forceful extraction, making disc retrieval easier. One such container requires a user to rotate its top and bottom components to free the disc from the hub. While ideal, this container proved to be of more complicated operation, and was more expensive to manufacture than conventional hub-retaining disc containers.
Furthermore, U.S. Pat. No. 5,402,882 discloses a disc container with an extractor mechanism that employs a barb affixed to its top inside surface. When the container is opened, the barb engages the bottom surface of the disc, pulling it upward and removing it from the hub automatically, and ultimately placing the disc on the top surface of the hub. While this device affords disc removal from the hub upon opening the container, it does not fully avoid the problem of forceful removal, as the extractor barb would require significant force to pull the disc off of the hub. This exertion could lead to both breakage of the barb member and damage to the disc.
U.S. Pat. No. 4,793,480 discloses an attempt to alleviate this problem by introducing a disc container with a pivotally mounted member that extends from between the juncture of the base and the lid. The extended member offers a way to retain a disc in the container, and to automatically disengage a disc from contact with the base upon opening the container. However, the extended member incorporates a hub-like clasp on which the disc is pressed when stored in the container. While the extending member automatically lifts the disc off of the base upon opening the container, the clasp-retaining mechanism on the extended member requires the user to exert force in freeing the disc therefrom; thus, the device suffers the same shortcomings as the other prior art described above.
Other less related inventions and patents include the record container of U.S. Pat. No. 1,554,995, the CD packages of U.S. Design Pat. No. Des. 360,360 and WIPO Patent No. 92/15505, and the folding device of German Patent No. 561,850.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.


A system for loading videos includes an interactive video player is with a loader. A product configuration file in operation configures files for a user in creation of a custom video. External assets are configured for a design of an interactive layer of the video. The interactive video player in operation creates in real-time a custom video that includes a plurality of video segments.

1. Field of the Invention
The present invention is directed to systems and methods for loading video content, and more particularly to systems and methods that load more than one video at the same time.
2. Description of the Related Art
All web servers are capable of progressive download. This is merely the method of delivering a video file via HTTP to a browser on the client side. The process is similar to downloading a file from any website but the difference is that media players can begin to play the video while it is downloading rather than having to wait until the entire video has been downloaded.
When a video is being delivered via HTTP progressive download, typically one sees the buffer bar grow as the video downloads. One is not able to watch the video if the scrubber button is moved past the amount that has downloaded already. This makes it impossible to jump to the end of the video. If the site has a slow web server or limited bandwidth, or the end user is on a slow Internet connection, then the end user will notice buffering. Buffering occurs when the download can't stay ahead of the video playback. In this instance, the video will stop and only after the player will download an additional portion of the video will the playing resume. If the user pauses the video and allows the downloading of a large portion of the video, the user will likely watch the video uninterrupted.
In almost all progressive downloading, there will be a certain amount of preloading, which means that a certain amount of video data is loaded, before the start of playback. Some players will begin to play a video as soon as a small amount of data is received and some will wait until the entire file is downloaded before it plays (in order to prevent buffering).
Current methods load the entire video and just one video is provided. Only after the video is finished playing can another one be loaded.
There is a need to provide improved systems and methods for loading videos. There is a further need for loading more than one video at a time.

This patent is subject to a terminal disclaimer.

Systems and methods for loading more than one video content at a time


A method, system and apparatus for server failure diagnosis and self-healing in a server farm. An autonomic server farm which has been configured in accordance with the inventive arrangements can include a multiplicity of servers enabled to respond to requests received from clients which are external to the server farm. A resource director such as an IP sprayer or a network dispatcher can be configured to route requests to selected ones of the servers, in accordance with resource allocation algorithms such as random, round-robin and least recently used. Significantly, unlike conventional server farms whose management of failure diagnosis and self-healing relies exclusively upon the capabilities of the resource director, in the present invention, client-assisted failure detection logic can be coupled to the resource director so as to provide client-assisted management of failure diagnosis and self-healing.

1. Statement of the Technical Field
The present invention relates to the field of autonomic computing and more particularly to the self-healing of a server farm.
2. Description of the Related Art
Beginning with the advent of enterprise computing, the complexity of computing technology has increased exponentially in pace with the increasing number innovative technologies available for deployment in the enterprise. The revered Moore's Law has driven tremendous growth in the information technology sector and has been seen as the cornerstone of technological advancement. Still, those at the forefront of deploying and managing new computing technologies have recognized that with the increasing number and complexity of computing technologies comes a price: technology management.
That is to say, the principal aim of interoperability has become increasingly more difficult to attain given the requirement that each component in the enterprise must be monitored and managed. Where in the past the enterprise had previously consisted but of a few, standardized components, presently, the enterprise can include a vast number of disparate components, each able to perform magnificently within specified operational parameters, or dismally outside specified operational parameters. Thus, while it may seem to the lay person that future challenges lie with the development of many new technologies having even more capabilities, one skilled in the art will recognize that the true, future challenge lies squarely within the management of technologies which likely already exist.
In the famed manifesto, Autonomic Computing: IBM's Perspective on the State of Information Technology, Paul Horn, Senior Vice President of IBM Research, observed, "It's not about keeping pace with Moore's Law, but rather dealing with the consequences of its decades-long reign." Given this observation, Horn suggested a computing parallel to the autonomic nervous system of the biological sciences. Namely, whereas the autonomic nervous system of a human being monitors, regulates, repairs and responds to changing conditions without any conscious effort on the part of the human being, in an autonomic computing system, the system must self-regulate, self-repair and respond to changing conditions, without requiring any conscious effort on the part of the computing system operator.
Thus, while the autonomic nervous system can relieve the human being from the burden of coping with complexity, so too can an autonomic computing system. Rather, the computing system itself can bear the responsibility of coping with its own complexity. The crux of the IBM manifesto relates to eight principal characteristics of an autonomic computing system:                I. The system must "know itself" and include those system components which also possess a system identify.        II. The system must be able to configure and reconfigure itself under varying and unpredictable conditions.        III. The system must never settle for the status quo and the system must always look for ways to optimize its workings.        IV. The system must be self-healing and capable of recovering from routine and extraordinary events that might cause some of its parts to malfunction.        V. The system must be an expert in self-protection.        VI. The system must know its environment and the context surrounding its activity, and act accordingly.        VII. The system must adhere to open standards.        VIII. The system must anticipate the optimized resources needed while keeping its complexity hidden from the user.
Notably, in accordance with the eight tenants of autonomic computing, several single system and peer-to-peer systems have been proposed in which self-configuration, management and healing have provided a foundation for autonomic operation. Yet, despite the eight tenants of autonomic computing, no existing implementation has addressed the interaction of client computing devices with server processes in a server farm so as to promote self-management and self-healing within the server farm. Rather, most server farms rely upon the use either of a periodic hear-beat mechanism, or the use of a "sprayer" in monitoring the health of servers in the server farm at the time the sprayer assigns a server to handle an incoming request.

International Business Machines Corporation


The invention teaches improved, novel methods and materials for the production of antennas. The invention contemplates the use of Directly Electroplateable Resins for the production of these antennas. The unique suitability of Directly Electroplateable Resins to allow facile manufacture of the antennas desired using a broad range of processing and manufacturing approaches is demonstrated.

The explosive proliferation of "wireless" electronic devices is to continue into the future. These ubiquitous items include cellular phones and pagers, so-called contactless "smart cards", radio frequency identification (RFID) tags and the emerging wireless data transmission devices. One common component of all these devices is an antenna. As is commonly considered, an antenna is an apparatus designed to receive, transmit, reflect and/or scatter electromagnetic waves or energy. Antennas come in many different forms depending on the requirements of the device. However, a common characteristic of many antennas is that they comprise a structural combination of conductive and dielectric insulating materials. One simple form of antenna involves formation of conductive traces or patches on a substantially flat surface. These conductive structures are included in many types of antenna designs, including coil, monopole, dipole and microstrip forms. Examples of these simple antenna structures are those incorporated into contactless "smart cards" and RFID tags. These antennas can be formed from a coil or loop of conductive line traces. The coil or loop antenna inductively powers the semiconductor chip and also accomplishes data transfer. The cards are generally restricted to a thickness of about 1 millimeter, which dictates that the conductive traces be substantially two dimensional in structure. This relatively simple geometry permits a number of manufacturing options to be considered. For example, U.S. Pat. No. 5,896,111 to Houdeau et al. teaches a technique whereby parallel conductor tracks are formed on strips of flexible, non-conductive carrier strips. The tracks were applied using printing technology, although a detailed description of the materials and processes used to form the tracks was not presented. Bending and connecting opposite ends of adjacent traces results in a substantially planar coil antenna. The technique requires stripping of insulation and individually connecting the opposite ends of adjacent traces which is time consuming and increases manufacturing costs.
U.S. Pat. No. 5,569,879 to Gloton, et al. teaches smart card production comprising lamination of a dielectric onto a prepunched metal strip. In one embodiment a portion of the metal strip is used as part of a microstrip antenna. However, the manufacture includes additional second surface metallization and possibly photo-etching which increases complexity and cost. An additional embodiment of the U.S. Pat. No. 5,569,879 patent shows a portion of the metal strip used as an inductor, but it is not clear how such a geometry would be supported prior to lamination to the dielectric strip.
U.S. Pat. No. 6,067,056 to Lake teaches methods of forming conductive lines and substantially planar antennas by selectively overcoating a first conductive layer with a patterned second conductive layer and etching to remove exposed portions of the first conductive layer. However, etching is wasteful and difficult from an environmental standpoint.
U.S. Pat. No. 5,809,633 to Mundigl et al. teaches manufacturing a coil antenna for a contactless smart card by winding wire in an automatic wire winding machine through a plurality of turns prior to placement on a carrier body. However, the wire used in a smart card antenna must be relatively thin to prevent unacceptable bulges in the final laminated card. Thus it would appear that the unsupported wire bending taught in U.S. Pat. No. 5,809,633 could be difficult to achieve in volume manufacturing.
U.S. Pat. No. 5,898,215 to Miller et al. describes smart card antennas embedded in a plastic laminate. The antenna is formed by winding an insulated copper wire, a process requiring removal of insulation in the region of contact. Alternate methods of manufacture for the antenna such as plating, etching, conductive ink printing and foil lamination were mentioned, although no specific process was taught in detail.
Other teachings for forming antenna structures on substantially flat surfaces involve printing the antenna design onto the surface using conductive inks or pastes. This method is taught, for example, in European Patent Publication EP 0942441A2 to Sugimura, PCT Publication WO 9816901A1 to Azdasht et al. and U.S. Pat. No. 5,900,841 to Hirata et al. These techniques suffer from the relatively high costs of the conductive inks and a high resistivity of these materials compared to substantially pure metals. It also may be difficult to make the required electrical contacts to these conductive inks.
U.S. Pat. No. 5,995,052 to Sadler, et al. and U.S. Pat. No. 5,508,709 to Krenz, et al. illustrate mobile phone antennas comprising conductive structures formed on substantially flat dielectric surfaces. Neither of these disclosures provided a detailed description of methods for forming and adhering the patterned conductive structures onto the dielectric surfaces.
Other techniques for formation of antenna structures on substantially flat surfaces utilize the photoetch technology widely employed for manufacture of printed circuits. These manufacturing techniques are taught in the "printed circuit" antenna structures of U.S. Pat. No. 5,709,832 to Hayes et al., U.S. Pat. No. 5,495,260 to Couture, and U.S. Pat. No. 5,206,657 to Downey. Hayes taught production of a printed monopole antenna, while Couture taught a dipole antenna produced using the circuit board techniques. Downey taught production of a coaxial double loop antenna by selective etching of a double metal cladded circuit board. These techniques involve creating a conductive antenna structure on a substantially flat surface through processes involving patterned etching. Techniques for producing antennas by selective etching suffer from excessive material waste, pollution control difficulties and limited design flexibility.
Another form of antenna often employed with wireless communication devices is the so-called "whip" antenna. These antennas normally comprise straight or helical coil wire structures, or combinations thereof, and are often moveable between extended and retracted positions. A typical example of such antenna design is taught in U.S. Pat. No. 5,995,050 to Moller, et al. Moller et al. teaches production of so-called extendable "whip" antennas combining wound helical and straight portions of wire. U.S. Pat. No. 6,081,236 to Aoki taught using a coaxial cable as a radiation element in conjunction with a helical antenna. U.S. Pat. No. 6,052,090 to Simmons, et al. teaches a combination of helical and straight radiating elements for multi-band use. The wire forming techniques proposed in these disclosures are, of course, limited in design flexibility. In many cases, the antenna and especially the helical coil must be encapsulated with insulating material for dimensional and structural integrity as well as aesthetic considerations. This encapsulation is often done by insert injection molding with a thermoplastic encapsulant. Care must be taken to ensure that the high injection pressures and speeds inherent in injection molding do not cause undesirable movement and dimensional changes of the wire coil. This problem was addressed by Bumsted in U.S. Pat. No. 5,648,788. However, the specialized tooling taught by Bumsted would appear to further reduce design flexibility and likely increase costs.
Other problems are associated with the "whip" antennas. They are subject to damage, especially when extended, and can cause inadvertent personal injury. The fact that they must be retractable increases mechanical wear and limits possible size reductions for the device. U.S. Pat. No. 6,075,489 to Sullivan addresses this latter problem by teaching a telescoping "whip" antenna combining a helix mounted on slideable components to enable telescopic extension. This design allows a longer antenna but increases complexity and cost and increases possibility of damage when extended.
As size continues to be an issue, increasing attention is devoted toward conformal antennas. Conformal antennas generally follow the shape of the surface on which they are supported and generally exhibit a low profile. There are a number of different types of conformal antennas, including microstrip, stripline, and three-dimensional designs. The low-profile resonant microstrip antenna radiators generally comprise a conductive radiator surface positioned above a more extensive conductive ground plane. The conductive surfaces are normally substantially opposing and spaced apart from one another. The substantially planar conductive surfaces can be produced by well-known techniques such as conductive coating, sheet metal forming or photo-etching of doubly clad dielectric sheet.
A factor to consider in design and construction of high efficiency microstrip antennas is the nature of the separating dielectric material. U.S. Pat. No. 5,355,142 to Marshall, et al. and U.S. Pat. No. 5,444,453 to Lalezari teach using air as the dielectric. This approach tends to increase the complexity of manufacture and precautions must be made to ensure and maintain proper spacing between radiator and ground plane.
U.S. Pat. No. 6,157,344 to Bateman, et al. teaches manufacture of flat antenna structures using well-known photomasking and etching techniques of copper cladded dielectric substrates.
U.S. Pat. No. 6,049,314 to Munson, et al., U.S. Pat. No. 4,835,541 to Johnson, et al. and U.S. Pat. No. 6,184,833 to Tran all teach manufacture of a microstrip antennas produced by cutting and forming an initially planar copper sheet into the form of a "U". Cutting and forming of planar metal sheets offers limited design options. In addition, provision must be made to provide a dielectric supporting structure between the two arms of the "U" since the sheet metal would likely not maintain required planar spacing without such support.
One notes that most of the technologies for antenna production involve the placement and combining of conductive material patterns with either a supportive or protective dielectric substrate. Antenna production often involves the production of well-defined patterns, strips or traces of conductive material held in position by a dielectric material.
As technology evolves, consumers have demanded a greater number of features incorporated in a specific device. These requirements tend to increase the size of the device. Simultaneously, there has been the need to make these portable devices smaller and lighter to maximize convenience. These conflicting requirements extend to the antenna, and attempts have been made to advance the antenna design toward three-dimensional structures to maximize performance and minimize size.
For example, U.S. Pat. No. 5,914,690 to Lehtola et al. teaches an internal conformal antenna of relatively simple, three dimensional construction for a wireless portable communication device. The antenna comprises an assembly of multiple pieces. A radiator plate is positioned between a cover structure and a support frame positioned over and connected to an electrically conductive earth plane. The radiator plate is formed from a flexible thin metal plate. The multiple pieces required for accurate positioning of the radiator plate relative to the earth plane increases the manufacturing cost of the Lehtola et al. structures.
Unfortunately, more complicated three-dimensional metal-based patterns often required for antenna manufacture can be difficult or impossible to produce using conventional mechanical wire winding, sheet forming or photoetching techniques. Photoetching requires a conforming mask to define the circuitry. U.S. Pat. No. 5,845,391 to Bellus, et al. illustrates the complications associated with prior art photoetch methods of forming three-dimensional metallic patterns on a dielectric substrate. Bellus, et al. teaches manufacture of a three-dimensional tapered notch antenna array formed on an injected molded thermoplastic grid. Multiple operations, specialized masking and other complications are involved in production of the photoetched metallic patterns. In addition, the metallic patterns produced were still restricted to a three dimensional structure made up of essentially flat dielectric panels.
Mettler et al., U.S. Pat. No. 4,985,116 taught the use of thermoforming a plastic sheet coated with a vacuum formable ink into a mask having the surface contour of a three dimensional article. A computer controlled laser is used to remove ink in a desired patterned design. The mask was then drawn tightly to a resist coated workpiece. Using known methods of photo and metal deposition processing, a part having patterned three-dimensional structure is produced. The Mettler, et al. patent also discussed the limitations of using a photomask on a three dimensional substrate by using the example of a mushroom. A photomask cannot easily conform to the stem of the mushroom while still permitting the mask to be installed or removed over the cap of the mushroom. Thus, a significant limitation on design flexibility exists with conventional photoetching techniques for production of three dimensional antenna structures.
A number of patents envision antenna structures comprising metal-based materials deposited into trenches or channels formed in a dielectric support. For example, Crothall in U.S. Pat. No. 5,911,454 teaches a method of forming a strip of conductive material by depositing a conductive material into a channel formed by two raised portions extending upward from a surface of an insulating material. The conductive material was deposited to overlay portions of the raised material. The conductive material overlaying the raised portions was then removed to result in a sharply defined conductive strip. The process taught by Crothall is clearly limited in its design flexibility by the material removal requirement. Ploussios, U.S. Pat. No. 4,862,184 teaches deposition of metal into a helical channel support. The selective deposition process was described only to the extent that it was achieved by known plating techniques. U.S. Pat. No. 4,996,391 to Schmidt and U.S. Pat. No. 4,985,600 to Heerman both teach injection molded substrates upon which a circuit is applied. In both patents, the pattern of the eventual circuitry is molded in the form of trenches or depressions below a major, substantially planar surface. In this way, plating resist lacquer applied by roller coating will coat only those surface areas of the major, substantially planar surface, and subsequent chemical metal deposition occurs only in the trenches remaining uncoated by the plating resist. This technique avoids the complications of photoetching, but is still design limited by the requirement of applying the plating resist. Application of the plating resist becomes increasingly difficult as the contours of the major surface become more complicated. In addition, chemical metal deposition is relatively slow in building thickness and the chemistry used is relatively expensive.
As wireless communication devices continue to evolve, the demands on the design, size and manufacturability of the required antennas will become increasingly challenging. There is clearly a need for improved materials, processes and manufacturing techniques to produce the antennas of the future.
U.S. Pat. No. 6,052,889 to Yu, et al. teaches a method for preparing a radio frequency antenna having a plurality of radiating elements. The three dimensional assembly includes multiple steps including electroless metal deposition on components to a metal thickness of at least 0.0015 inch. Electroless metal deposition involves relatively slow deposition rates and thus extended processing times are required to deposit such thickness. The Yu, et al. teaching also involves photoetching to selectively remove metal, further complicating the methods taught.
Elliott, in U.S. Pat. No. 6,147,660 addresses the design limitations intrinsic in helical wire-winding processing and teaches use of a molded helical antenna. Techniques taught to produce the molded antennas included zinc die casting, metal injection molding, or molding of a material such as ABS, which can be plated by conventional technology. Elliot taught non-circular or non-symmetrical helical antennas, difficult to manufacture by conventional wire winding methods. The manufacturing methods proposed would be difficult and costly.
A number of recent approaches to production of improved antennas involve a technology generally described as "plating on plastics". The "plating on plastics" technology is intended to deposit an adherent coating of a metal or metal-based material onto the surface of a plastic substrate. Conventional "plating on plastics" typically envisions the deposition of an initial metal coating using "electroless" plating followed by an optional deposition of additional metal using electrodeposition. Electroless plating of a plastics involves chemically coating a nonconductive surface such as a plastic with a metallic film. Unlike conventional electroplating, electroless plating does not require the use of electricity to deposit the metal. Instead, a series of chemical steps involving etchants and catalysts prepare the non-conductive plastic substrate to accept a metal layer deposited by chemical reduction of metal from solution. The process often involves depositing a thin layer of highly conductive copper followed by a nickel topcoat, which protects the copper sublayer from oxidation and corrosion. The thickness of the nickel topcoat can be adjusted depending on the abrasion and corrosion requirements of the final product. Because electroless plating is an immersion process, uniform coatings can be applied to almost any configuration regardless of size or complexity. Electroless plating also provides a conductive, essentially pure metal surface. Electrolessly plated parts can be subsequently electroplated if required.
Unfortunately, the "plating on plastics" process comprises many steps involving expensive and harsh chemicals. This increases costs dramatically and involves environmental difficulties. The process can be sensitive to processing variables used to fabricate the plastic substrate, limiting applications to carefully molded parts and designs. It may be difficult to properly mold conventional plateable plastics using the rapid injection rates often required for the thin walls of electronic components. The rapid injection rates can cause poor surface distribution of etchable species, resulting in poor surface roughening and subsequent inferior bonding of the chemically deposited metal. Finally, the rates at which metals can be chemically deposited are relatively slow, typically about one micrometer per hour. The conventional technology for metal plating on plastic (etching, chemical reduction, optional electroplating) has been extensively documented and discussed in the public and commercial literature. See, for example, Saubestre, Transactions of the Institute of Metal Finishing, 1969, Vol. 47, or Arcilesi et al., Products Finishing, March 1984.
Despite the difficulties, a number of attempts have been made to utilize the "plating on plastics" technology for the production of antennas. Most antenna applications involve selective placement of a metal conductor in relation to an insulating material. Selective metallization using the "plating on plastics" technology can be achieved in a number of ways. A first method is to coat the entire insulating substrate with metal and then selectively remove metal using photoetching techniques that have been used for many years in the production of printed circuits. However, these techniques are very limited in design flexibility, as discussed previously. A second method is to apply a plating stopoff coating prior to chemically depositing the metal. The stopoff is intended to prevent metal deposition onto the coated surfaces. This approach was incorporated into the teachings of Schmidt, U.S. Pat. No. 4,996,391, and Heerman, U.S. Pat. No. 4,985,600 referenced above. This approach is design limited by the need for the stopoff coating. Another more recent approach is to incorporate a plating catalyst into a resin and to combine the "catalyzed resin with an "uncatalyzed" resin in a two shot molding operation. Only the surfaces formed by the "catalyzed" resin will stimulate the chemical reaction reducing metal, and thus conceptually only those surfaces will be metallized. This approach is taught, for example, in U.S. Pat. No. 6,137,452 to Sullivan.
Selective metallizing using either stopoff lacquer of catalyzed resin approaches can be difficult, especially on complex parts, since the electroless plating may tend to coat any exposed surface unless the overall process is carefully controlled. Poor line definition, "skip plating" and complete part coverage due to bath instabilities often occurs. Despite much effort to develop consistent and reliable performance through material and process development, these problems still remain.
There is a clear need for improved technology to enable facile production of antennas comprising electroplated plastic structures.
A number of attempts have been made to simplify the electroplating of plastics. If successful such efforts could result in significant opportunities as well as cost reductions for electroplated plastics used for antennas. In addition expanded possibilities such as the continuous manufacture of low-cost antennas could be envisioned. Some simplification attempts involve special chemical techniques, other than conventional electroless metal deposition, to produce an electrically conductive film on the surface. Typical examples of the approach are taught by U.S. Pat. No. 3,523,875 to Minklei, U.S. Pat. No. 3,682,786 to Brown et al., and U.S. Pat. No. 3,619,382 to Lupinski. The electrically conductive surface film produced was intended to be electroplated. Multiple performance problems thwarted these attempts.
Other approaches contemplate making the plastic surface itself conductive enough to allow it to be electroplated directly thereby avoiding the "electroless plating" processes. Polymers can be made electrically conductive through incorporation of conductive fillers. Alternatively, intrinsically conductive polymers are known in the art.
Efforts have been made to advance systems contemplating metal electrodeposition directly onto the surface of electrically conductive polymers made conductive through incorporating conductive fillers. When considering polymers rendered electrically conductive by loading with electrically conductive fillers, it may be important to distinguish between "microscopic resistivity" and "bulk" or macroscopic resistivity". "Microscopic resistivity" refers to a characteristic of a polymer/filler mix considered at a relatively small linear dimension of for example 1 micrometer or less. "Bulk" or "macroscopic resistivity" refers to a characteristic determined over larger linear dimensions. To illustrate the difference between "microscopic" and "bulk, macroscopic" resistivities, one can consider a polymer loaded with conductive fibers at a fiber loading of 10 weight percent. Such a material might show a low "bulk, macroscopic" resistivity when the measurement is made over a relatively large distance. However, because of fiber separation (holes) such a composite might not exhibit consistent "microscopic" resistivity. When producing an electrically conductive polymer intended to be electroplated, one should consider "microscopic resistivity" in order to achieve uniform, "hole-free" deposit coverage. Thus, it may be advantageous to consider conductive fillers comprising those that are relatively small, but with loadings sufficient to supply the required conductive contacting. Such fillers include metal powders and flake, metal coated mica or spheres, conductive carbon black and the like.
Efforts to produce electrically conductive polymers suitable for direct electroplating have encountered a number of obstacles. The first is the combination of fabrication difficulty and material property deterioration brought about by the heavy filler loadings often required. A second is the high cost of many conductive fillers employed such as silver flake.
Another obstacle involved in the electroplating of electrically conductive polymers is a consideration of adhesion between the electrodeposited metal and polymeric substrate (metal/polymer adhesion). In some cases such as electroforming, where the electrodeposited metal is eventually removed from the substrate, metal/polymer adhesion may actually be detrimental. However, in most cases sufficient adhesion is required to prevent metal/polymer separation during extended environmental and use cycles.
A number of methods to enhance adhesion have been employed. For example, etching of the surface prior to plating can be considered. Etching can be achieved by immersion in vigorous solutions such as chromic/sulfuric acid. Alternatively, or in addition, an etchable species can be incorporated into the conductive polymeric compound. The etchable species at exposed surfaces is removed by immersion in an etchant prior to electroplating. Oxidizing surface treatments can also be considered to improve metal/plastic adhesion. These include processes such as flame or plasma treatments or immersion in oxidizing acids.
In the case of conductive polymers containing finely divided metal, one can propose achieving direct metal-to-metal adhesion between the electrodeposit and the filler. However, here the metal particles are generally encapsulated by the resin binder, often resulting in a resin rich "skin". To overcome this effect, one could propose methods to remove the "skin", exposing active metal filler to bond to subsequently electrodeposited metal.
Another approach to impart adhesion between conductive resin substrates and electrodeposits is incorporation of an "adhesion promoter" at the surface of the electrically conductive resin substrate. This approach was taught by Chien et al. in U.S. Pat. No. 4,278,510 where maleic anhydride modified propylene polymers were taught as an adhesion promoter. Luch, in U.S. Pat. No. 3,865,699 taught that certain sulfur bearing chemicals could function to improve adhesion of initially electrodeposited Group VIII metals.
An additional major obstacle confronting development of electrically conductive polymeric resin compositions capable of being directly electroplated is the initial "bridge" of electrodeposit on the surface of the electrically conductive resin. In electrodeposition, the substrate to be plated is often made cathodic through a pressure contact to a metal rack tip, itself under cathodic potential. However, if the contact resistance is excessive or the substrate is insufficiently conductive, the electrodeposit current favors the rack tip to the point where the electrodeposit will have difficulty bridging to the substrate.
Moreover, a further problem is encountered even if specialized racking successfully achieves electrodeposit bridging to the substrate. Many of the electrically conductive polymeric resins have resistivities far higher than those of typical metal substrates. The polymeric substrate can be relatively limited in the amount of electrodeposition current which it alone can convey. Thus, in these cases the conductive polymeric substrate may not cover almost instantly with electrodeposit as is typical with metallic substrates. Rather the electrodeposit coverage occurs by lateral growth over the surface. Except for the most heavily loaded and highly conductive polymer substrates, a significant portion of the electrodeposition current, including that associated with the lateral electrodeposit growth, must pass through the previously electrodeposited metal. In a fashion similar to the bridging problem discussed above, the electrodeposition current favors the electrodeposited metal and the lateral growth can be extremely slow and erratic. This restricts the size and "growth length" of the substrate conductive pattern which can reasonably be employed, increases plating costs, and can also result in large non-uniformities in electrodeposit integrity and thickness over the pattern.
Lateral electrodeposit coverage rate issues likely can be characterized by a continuum, being dependent on many factors such as the nature of the initially electrodeposited metal, electroplating bath chemistry and operational parameters, the polymeric binder, resistivity, and the thickness of the conductive polymeric substrate. In many cases, thin electrodeposited metal patterns having extended length are desired. Often, these patterns are to be electroplated on electrically conductive polymeric substrates having limited current carrying capacity. For example, a pattern formed using a typical electrically conductive coating or ink may have a dry thickness less than 25 micrometers, and often less than about 10 micrometers. In these cases, lateral electrodeposit coverage rates may be of concern even for highly conductive inks.
In addition to thickness, an additional factor affecting substrate current carrying capacity is resistivity. As an additional rule of thumb, the instant inventor estimates that coverage rate problems would demand attention if the resistivity of the conductive polymeric substrate rose above 0.001 ohm-cm regardless of thickness.
Beset with the problems of achieving adhesion and satisfactory electrodeposit coverage rates, investigators have attempted to produce directly electroplateable polymers by heavily loading polymers with relatively small metal containing fillers to create electrically conductive polymers. Such heavy loadings are sufficient to reduce both microscopic and macroscopic resistivity to a level where the coverage rate phenomenon may be manageable. However, attempts to make an acceptable directly electroplateable resin using the relatively small metal containing fillers alone encounter a number of barriers. First, the fine metal containing fillers are relatively expensive. The loadings required to achieve the particle-to-particle proximity for acceptable conductivity increases the cost of the polymer/filler blend dramatically. The metal containing fillers are accompanied by further problems. They tend to cause deterioration of the mechanical properties and processing characteristics of many resins. This significantly limits options in resin selection. All polymer processing is best achieved by formulating resins with processing characteristics specifically tailored to the specific process (injection molding, extrusion, blow molding, printing etc.). A required heavy loading of metal filler severely restricts ability to manipulate processing properties in this way. A further problem is that metal fillers can be abrasive to processing machinery and may require specialized screws, barrels, and the like. Finally, despite being electrically conductive, a simple metal-filled polymer still offers no mechanism to produce adhesion of an electrodeposit since the metal particles are generally encapsulated by the resin binder, often resulting in a resin-rich "skin". For the above reasons, fine metal particle containing plastics have not been widely used as substrates for discrete self supporting directly electroplateable articles. Rather, they have found applications in production of conductive adhesives, pastes, and paints.
The least expensive (and least conductive) of the readily available conductive fillers for plastics are carbon blacks. Attempts have been made to produce electrically conductive polymers based on carbon black loading intended to be subsequently electroplated. Examples of this approach are the teachings of U.S. Pat. Nos. 4,038,042, 3,865,699, and 4,278,510 to Adelman, Luch, and Chien et al. respectively.
Adelman taught incorporation of conductive carbon black into a polymeric matrix to achieve electrical conductivity required for electroplating. The substrate was pre-etched in chromic/sulfuric acid to achieve adhesion of the subsequently electroplated metal. However, the rates of electrodeposit coverage reported by Adelman may be insufficient for many applications.
Luch in U.S. Pat. No. 3,865,699 and Chien et al. in U.S. Pat. No. 4,278,510 also chose carbon black as a filler to provide an electrically conductive surface for the polymeric compounds to be electroplated. The Luch U.S. Pat. No. 3,865,699 and the Chien U.S. Pat. No. 4,278,510 are hereby incorporated in their entirety by this reference. However, these inventors further taught inclusion of materials to increase the rate of metal coverage or the rate of metal deposition on the polymer. These materials can be described herein as "electrodeposit growth rate accelerators" or "electrodeposit coverage rate accelerators". An electrodeposit coverage rate accelerator is a material functioning to increase the electrodeposition coverage rate over the surface of an electrically conductive polymer independent of any incidental affect it may have on the conductivity of an electrically conductive polymer. In the embodiments, examples and teachings of U.S. Pat. Nos. 3,865,699 and 4,278,510, it was shown that certain sulfur bearing materials, including elemental sulfur, can function as electrodeposit coverage or growth rate accelerators to overcome problems in achieving electrodeposit coverage of electrically conductive polymeric surfaces having relatively high resistivity or thin electrically conductive polymeric substrates having limited current carrying capacity.
In addition to elemental sulfur, sulfur in the form of sulfur donors such as sulfur chloride, 2-mercapto-benzothiazole, N-cyclohexyle-2-benzothiaozole sulfonomide, dibutyl xanthogen disulfide, and tetramethyl thiuram disulfide or combinations of these and sulfur were identified. Those skilled in the art will recognize that these sulfur donors are the materials which have been used or have been proposed for use as vulcanizing agents or accelerators. Since the polymer-based compositions taught by Luch and Chien et al. could be electroplated directly they could be accurately defined as directly electroplateable resins (DER). These DER materials can be generally described as electrically conductive polymers characterized by having an electrically conductive surface with the inclusion of an electrodeposit coverage rate accelerator. In the following, the acronym "DER" will be used to designate a directly electroplateable resin as defined in this specification.
Specifically for the present invention, directly electroplateable resins, (DER), are characterized by the following features:                (a) presence of an electrically conductive polymer characterized by having an electrically conductive surface;        (b) presence of an electrodeposit coverage rate accelerator;        (c) presence of the electrically conductive polymer characterized by having an electrically conductive surface and the electrodeposit coverage rate accelerator in the directly electroplateable composition in cooperative amounts appropriate to allow direct coverage of the composition with an electrodeposited metal or metal-based alloy.
In his patents, Luch specifically identified elastomers such as natural rubber, polychloroprene, butyl rubber, chlorinated butyl rubber, polybutadiene rubber, acrylonitrile-butadiene rubber, styrene-butadiene rubber etc. as suitable for the matrix polymer of a directly electroplateable resin. Other polymers identified by Luch as useful included polyvinyls, polyolefins, polystyrenes, polyamides, polyesters and polyurethanes.
In his patents, Luch identified carbon black as a means to render a polymer and its surface electrically conductive. As is known in the art, other conductive fillers can be used to impart conductivity to a polymer. These include metallic flakes or powders such as those comprising nickel or silver. Other fillers such as metal coated minerals may also suffice. Furthermore, one might expect that compositions comprising intrinsically conductive polymers may be suitable.
Regarding electrodeposit coverage rate accelerators, both Luch and Chien et al. in the above discussed U.S. patents demonstrated that sulfur and other sulfur bearing materials such as sulfur donors and vulcanization accelerators function as electrodeposit coverage rate accelerators when using an initial Group VIII "strike" layer. Thus, an electrodeposit coverage rate accelerator need not necessarily be electrically conductive, but may be a material that is normally characterized as a non-conductor. The coverage rate accelerator need not appreciably affect the conductivity of the polymeric substrate. As an aid in understanding the function of an electrodeposit coverage rate accelerator the following is offered:                a. A specific conductive polymeric structure is identified as having insufficient current carry capacity to be directly electroplated in a practical manner.        b. A material is added to the conductive polymeric material forming said structure. Said material addition may have insignificant affect on the current carrying capacity of the structure (i.e. it does not appreciably reduce resistivity or increase thickness).        c. Nevertheless, inclusion of said material greatly increases the speed at which an electrodeposited metal laterally covers the electrically conductive surface.It is contemplated that a coverage rate accelerator may be present as an additive, as a species absorbed on a filler surface, or even as a functional group attached to the polymer chain.
A hypothetical example might be an extended trace of conductive ink having a dry thickness of 1 micrometer. Such inks typically include a conductive filler such as silver, nickel, copper, conductive carbon etc. The limited thickness of the ink reduces the current carrying capacity of this trace thus preventing direct electroplating in a practical manner. However, inclusion of an appropriate quantity of a coverage rate accelerator may allow the conductive trace to be directly electroplated in a practical manner.
One might expect that other Group 6A elements, such as oxygen, selenium and tellurium, could function in a way similar to sulfur. In addition, other combinations of electrodeposited metals, such as copper, and appropriate coverage rate accelerators may be identified. It is important to recognize that such an electrodeposit coverage rate accelerator is extremely important in order to achieve direct electrodeposition in a practical way onto polymeric substrates having low conductivity or very thin electrically conductive polymeric substrates having restricted current carrying ability.
It has also been found that the inclusion of an electrodeposit coverage rate accelerator promotes electrodeposit bridging from a discrete cathodic metal contact to a DER surface. This greatly reduces the bridging problems described above.
As pointed out above in this specification, attempts to dramatically simplify the process of electroplating on plastics have met with commercial difficulties. Nevertheless, the current inventor has persisted in personal efforts to overcome certain performance deficiencies associated with the initial DER technology. Along with these efforts has come a recognition of unique and eminently suitable applications employing electrically conductive polymers and specifically the DER technology especially for those applications related to antenna manufacture.
A first recognition, is that the "microscopic" material resistivity generally is not reduced below about 1 ohm-cm. by using conductive carbon black alone. This is several orders of magnitude larger than typical metal resistivities. Other well known finely divided conductive fillers (such as metal flake or powder, metal coated minerals, graphite, or other forms of conductive carbon) can be considered in DER applications requiring lower "microscopic" resistivity. In these cases the more highly conductive fillers can be considered to augment or even replace the conductive carbon black.
Moreover, the "bulk, macroscopic" resistivity of conductive carbon black filled polymers can be further reduced by augmenting the carbon black filler with additional highly conductive, high aspect ratio fillers such as metal containing fibers. This can be an important consideration in the success of certain applications. Furthermore, one should realize that incorporation of non-conductive fillers may increase the "bulk, macroscopic" resistivity of conductive polymers loaded with finely divided conductive fillers without significantly altering the "microscopic resistivity" of the conductive polymer. This is an important recognition regarding DER's in that electrodeposit coverage speed depends not only on the presence of an electrodeposit coverage rate accelerator but also on the "microscopic resistivity" and less so on the "macroscopic resistivity" of the DER formulation. Thus, large additional loadings of functional non-conductive fillers can be tolerated in DER formulations without undue sacrifice in electrodeposit coverage rates or adhesion. These additional non-conductive loadings do not greatly affect the "microscopic resistivity" associated with the polymer/conductive filler/electrodeposit coverage rate accelerator "matrix" since the non-conductive filler is essentially encapsulated by "matrix" material. Conventional "electroless" plating technology does not permit this compositional flexibility.
Yet another recognition regarding the DER technology is its ability to employ polymer resins generally chosen in recognition of the fabrication process envisioned and the intended end use requirements. Thus DER's can be produced in material forms that are often suitable for the manufacture of antennas. In order to provide clarity, examples of some such fabrication processes are presented immediately below in subparagraphs 1 through 7.                (1) Should it be desired to electroplate an ink, paint, coating, or paste which may be printed or formed on a substrate, a soluble resin having excellent film forming characteristics can be chosen to fabricate a DER ink (paint, coating, paste etc.).        (2) Very thin DER traces often associated with antenna structure can be printed and then electroplated due to the inclusion of a growth rate accelerator.        (3) DER inks have been formulated such that very fine line definition can be achieved with standard printing processes such as flexographic printing and rotary screen printing.        (4) Should it be desired to electroplate an antenna on a fabric, a DER ink can be used to coat all or a portion of the fabric intended to be electroplated. Furthermore, since DER's can be fabricated out of the thermoplastic materials commonly used to create fabrics, the fabric itself could completely or partially comprise a DER. This would obviously eliminate the need to coat the fabric.        (5) Should one desire to electroplate a thermoformed antenna, DER's would represent an eminently suitable material choice. DER's can be easily formulated using olefinic materials which are often a preferred material for the thermoforming process. Furthermore, DER's can be easily and inexpensively extruded into the sheet like structure necessary for the thermoforming process.        (6) Should one desire to electroplate an extruded antenna, for example a sheet or film, DER's can be formulated to possess the necessary melt strength advantageous for the extrusion process.        (7) Should one desire to electroplate a blow molded antenna, DER's can fabricated with required melt strength etc. necessary for these operations.        (8) Should one desire to electroplate an injection molded antenna having thin walls, broad surface areas etc. a DER composition comprising a high flow polymer can be chosen.        (9) One will recognize that DER's are eminently suitable for specialized injection molding techniques such as multi-shot molding, dual shot molding, co-injection molding, insert molding etc.        (10) Should one desire to vary adhesion between an electrodeposited DER structure supported by a substrate the DER material can be formulated to supply the required adhesive characteristics to the substrate.
All polymer fabrication processes require specific resin processing characteristics for success. The ability to "custom formulate" DER's to comply with these changing processing and end use requirements while still allowing facile, quality electroplating is a significant factor in the antenna manufacture teachings of the current invention. Conventional plastic electroplating technology does not permit great flexibility to "custom formulate".
Another important recognition regarding the suitability of DER's for antenna manufacturing is the simplicity of the electroplating process. Unlike many conventional electroplated plastics, DER's do not require a significant number of process steps during the manufacturing process. This allows for simplified manufacturing and improved process control. It also reduces the risk of cross contamination such as solution dragout from one process bath being transported to another process bath. The simplified manufacturing process will also result in reduced manufacturing costs. As will be shown in the subsequent embodiments, this simplified manufacturing also allows unique electrical joining techniques between antennas and electrical devices.
Another important recognition regarding the suitability of DER's for antenna production, is the wide variety of metals and alloys capable of being electrodeposited. Deposits may be chosen for specific attributes. An example is copper for conductivity. Another example would be iron for its magnetic, cost or environmental characteristics.
Yet another recognition of the benefit of DER's for antenna manufacturing is the ability they offer to selectively electroplate an article or structure. Antennas often consist of metal patterns selectively positioned in conjunction with insulating materials. Such selective positioning of metals is often expensive and difficult. However, the attributes of the DER technology make the technology eminently suitable for the production of such selectively positioned metal structures. As will be shown in later embodiments, selective electroplating of a DER/insulating antenna structure can be simply and inexpensively achieved.
Yet another recognition of the benefit of DER's for antenna manufacturing is the ability they offer to continuously electroplate an article or structure. As will be shown in later embodiments, it is often desired to continuously electroplate articles to form electroplated plastic antennas. Examples include antennas for RFID tags and contactless smart cards. DER's are eminently suitable for such continuous electroplating. Furthermore, DER's allow for the selective electroplating of antennas in a continuous manner.
Yet another recognition of the benefit of DER's for antenna manufacturing is their ability to withstand the pre-treatments often required to prepare other materials for electroplating. For example, were a DER to be combined with another electroplateable material, the DER material would be resistant to many of the pre-treatments which may be necessary to electroplate the additional electroplateable material.
Yet another recognition of the benefit of DER's for antenna manufacturing is that the desired plated structure often requires the plating of long and/or broad surface areas. As discussed previously, the coverage rate accelerators included in DER formulations allow for such extended surfaces to be covered in a relatively rapid manner.
These and other attributes of DER's in the production of antennas will become clear through the following remaining specification, accompanying figures and claims.
In order to eliminate ambiguity in terminology of the present specification and claims, the following definitions are supplied.
"Polymers" (also referred to as plastics or resins) include any of the group of synthetic or natural organic materials that may be shaped when soft and then hardened. This includes thermoplastics and three-dimensional curing materials such as epoxies and thermosets. In addition, certain silicon based materials such as silicones can be considered as polymers or resins. Polymers also include any coating, ink, or paint fabricated using a polymer binder or film forming material.
"Alloy" refers to a substance composed of two or more intimately mixed materials.
"Metal-based" refers to a material or structure having at least one metallic property and comprising one or more components at least one of which is a metal or metal-containing alloy.
"Group VIII metal-based" refers to a substance containing by weight 50% to 100% metal from Group VIII of the Periodic Table of Elements.

Electrically conductive patterns, antennas and methods of manufacture


A method for the control of a wound rotor synchronous motor comprises measuring a plurality of electromagnetic entities indicative of the operation of the motor, generating voltage on a stator of the motor to obtain a stator current, further generating a further voltage on the rotor to obtain a rotor current, before the generating and the further generating, the entities being processed to calculate references for the stator current and for the rotor current, the references corresponding to the generation by the motor of the maximum torque obtainable per ampere of stator current supplied.

This application is a National Stage of PCT International Application No. PCT/IB2005/002552 filed Aug. 29, 2005 which claims priority to IT Application No. MO2004A000218 filed Aug. 31, 2004. The entire contents of these applications are incorporated herein by reference.
The invention relates to a method for the control of a wound rotor synchronous motor, particularly but not exclusively suitable for traction of an electric vehicle, for example a forklift truck, and for use in automatic machines, machine tools, lifting machines, industrial robots, and for ship propulsion.
Electric vehicles are known that use drives based on direct-current motors or induction motors or permanent magnet synchronous motors, having different configurations (internal magnets, hybrid motors, etc) coupled with suitable power converters. In these types of drive, the capability of reaching high torque at low speed can be obtained only by injecting a high current into the motor stator windings. Maximum torque is mainly limited by the maximum current obtainable from the electronic converter.
This limitation is due to the high cost per ampere of the electronic power converter and its limited overload capability in terms of peak current and overload time. Oversizing of the power electronic converter is the method that is usually employed to inject high current into the motor and to reach the desired performance at low speed.
This solution often leads to very high costs that can discourage the implementation of drives for heavy electric vehicles powered by a group of standard lead-acid batteries at low voltage (<100V).
The possibility of obtaining constant power operation over a wide speed range has been studied for different configurations of internal permanent magnet synchronous motors (indicated by the acronym IPM-SM standing for "Internal Permanent Magnet Synchronous Motor" in English). In these types of motor, the machine parameters that allow constant power operation up to a high speed do not match the machine parameters required to reach high torque at low speed.
Some solutions have been presented for extending the constant power region without compromising the capability of obtaining high torque at low speed.
The aforementioned solutions include hybrid machines composed of a two-part rotor and comprising a surface magnet part and a reluctance part, field windings positioned in the stator that change the level of excitation produced by the permanent surface magnets, movable parts on both sides of the rotor that short-circuit the flux path, reducing the flux-linkage with the stator produced by the permanent magnets.
In industrial applications requiring constant power operation over a wide speed range an alternative solution to internal permanent magnet synchronous motors (IPM-SM) is represented by wound rotor synchronous motors (indicated as "WR-SM", the English acronym for "wound rotor synchronous motor").
In particular, synchronous motors are used for large drives, such as for example ship propulsion and in rolling mill drives. These motors are used because of their high efficiency, high overload capability and good performance in the field-weakening region.
FIG. 1 shows a comparison between the expected performance of a WR-SM and of an IPM-SM in terms of torque and power in function of speed. For the comparison, it is assumed that both motors have the same rated power and the same rated current.
As shown in FIG. 1, a drive based on a WR-SM is suitable for meeting the requirement for high starting torque at low speed that is typical of electric vehicles and for operation at constant power over a wide speed range.
The use of traction systems based on WR-SM in electrical vehicles is proposed in WO9013454.
However, this patent document does not propose a control method at the instantaneous values of a WR-SM.
An object of the present invention is to obtain a method for the control of a wound rotor synchronous motor.
A further object is to obtain a method that enables the operation of a wound rotor synchronous motor to be controlled instant by instant, which wound rotor synchronous motor is arranged to drive an electric vehicle in such a way as to obtain high starting torque and at low operating speed, and constant power operation at high speed.
According to the invention, there is provided a method for controlling a wound rotor synchronous motor, comprising measuring a plurality of electromagnetic entities indicative of the operation of said motor, generating voltage on a stator of said motor to obtain stator currents, further generating further voltage on said rotor to obtain a rotor current, wherein said method further comprises, before said generating and said further generating, processing said entities to calculate references for said stator currents and for said rotor current, said references corresponding to the generation by said motor of the maximum torque obtainable per ampere of stator current supplied.
Owing to the invention, it is possible to obtain a method for controlling a wound rotor synchronous motor that is able to obtain the maximum torque per ampere of stator current in the entire operating field of the motor.
This method is based on the study of instantaneous machine values in linear conditions. The application of the linear model to the real machine operating in the saturation conditions of the magnetic circuit, and therefore in non-linear conditions, is possible by means of a linearization procedure carried out for each operating point. The method uses a flux estimator for estimating machine stator flux. Estimated flux is used to calculate parameters to be inserted into the linear model. By means of the equations of the linear model the optimal supply conditions are identified for each machine operating point, the optimal supply condition complying with operating conditions existing at that point.
Owing to the invention, it is possible to make an electric drive based on the use of a wound rotor synchronous motor that is particularly suitable for the traction of electric vehicles.
Drives based on WR-SM controlled by the method according to the invention are able to generate high torque at low speed by overloading the excitation winding and keeping the stator current at acceptable values, thus avoiding excessive oversizing of the electronic power converter, which supplies the stator.
Furthermore, the possibility of regulating the excitation current enables the machine to operate at constant power up to a theoretically unlimited speed.
These torque-delivering features of the WR-SM machine furthermore meet the electric traction requirements.
The drives disclosed above require an excitation winding on the rotor, brush slip rings for supplying the excitation winding and a direct-current/direct-current chopper for regulating the excitation current. These components are based on consolidated technologies and do not cause a significant increase in the cost of the drives.

Method for controlling a wound rotor synchronous motor

C.A.R.E.R. Carrellificio Elettrico Romagnolo Dell'Ing. Angelo Gaetani E C.S.N.C.


Transitive restrictions can be applied to requests received on a session. A session token can be issued for an active session, and a transitivity setting specified to indicate the types of requests for which the transitive restriction is to be enforced. This can include enforcing the restriction on requests received from outside a trusted environment, requests within a scope of enforcement, or enforcing the restriction at request authentication. Any request received from an untrusted source that fails to satisfy the transitive restriction will be denied. Requests from inside the trusted environment may not have the transitive restriction enforced, such as where a new token is issued. This enables services within the environment to make calls on behalf of the customer, while ensuring that third parties obtaining the session token cannot successfully initiate such calls.

Users are increasingly performing tasks using remote computing resources, often referred to as part of "the cloud." This has many advantages, as users do not have to purchase and maintain dedicated hardware and software, and instead can pay for only those resources that are needed at any given time, where those resources typically will be managed by a resource provider. Because a resource provider will often provide resource access to many different users, various types of credentials can be used to authenticate a source of the request, as well as to demonstrate that the source is authorized to access a resource to perform a task. These credentials can potentially be obtained by unintended third parties, who can gain unauthorized access to the resource environment, as well as the data and content stored therein. In order to minimize this potential problem, credentials can be given various restrictions to minimize the ability of an unauthorized third party to utilize the credentials. Unfortunately, these restrictions can prevent certain other authorized uses of the credentials that are to be performed on behalf of the users authorized for those credentials.

Restriction transitivity for session credentials


An image processing apparatus capable of obtaining a gamma characteristic (non-linear conversion characteristic) giving consideration to a difference between light and dark parts in a subject region is provided along with a method for controlling the same. A value indicating the difference between light and dark parts in the subject region is calculated based on image data. Then, by interpolating multiple basic gamma characteristics using the value indicating the difference between light and dark parts, a gamma characteristic depending on the difference between light and dark parts is generated and applied to the image data.

1. Field of the Invention
The present invention relates to an image processing apparatus and a method for controlling the same, and in particular relates to an image forming apparatus that applies a non-linear conversion to an image to improve image quality, and a method for controlling the same.
2. Description of the Related Art
It is known that gamma correction is performed in order to adjust tone in a captured image in a conventional digital still camera, digital video camera, or the like. Gamma correction is non-linear conversion that is performed with respect to the luminance of a captured image, and a non-linear conversion characteristic is also referred to as a gamma characteristic, a gamma curve, or the like.
By correcting a gamma characteristic in accordance with the features of an image, it is possible to restrain blown-out highlights and blocked-up shadows in an image. Japanese Patent Laid-Open No. 2007-201655 discloses that the occurrence of blown-out highlights that appear when a reference gamma characteristic is applied is predicted based on the ratio of frequencies in four equal regions of an image density (luminance) histogram, and the reference gamma characteristic is corrected such that blown-out highlights are restrained.
Japanese Patent Laid Open No. 2007-201655 also discloses that if, based on the average density of a face region, it is predicted that an unpleasant influence will appear in the image quality of the face region when the corrected reference gamma characteristic is applied, the gamma characteristic is further corrected in order to avoid the unpleasant influence.
Since a face is not a flat region, with general shooting conditions in which light comes from an oblique direction with respect to the face, there is a difference between light and dark parts in the face region and the difference between light and dark parts varies according to the positional relationship between the face and the light source, the intensity of the light source, and the like. However, in Japanese Patent Laid-Open No. 2007-201655, no correction or setting of a gamma characteristic that gives consideration to the difference between light and dark regions in a face region is considered, and the post-correction gamma characteristic may not necessarily be appropriate for the image quality of the face region.

Image processing apparatus and method for controlling the same for obtaining and applying gamma characteristics to reduce a difference between light and dark areas of an image


A method of identifying at least one pole location on a bearing element formed from a metal source element. The method is non-destructive and does not alter the surface of the bearing element. The method includes applying X-rays to a plurality of regions of a bearing element, and measuring diffracted intensity values of X-ray diffraction vectors or bi-sectors at the plurality of regions. The method includes determining at least one pole location on the bearing element based on the diffracted intensity values.

It is well known that bearing elements, such as ball bearings, can be formed from a source material in a rod form. The bearing elements formed from the rod will have particular characteristics due to the inherent characteristics or properties of the source material. One known type of material for forming bearing elements is steel.
Due to the forging associated with forming bearing elements from a rod or cylinder of source material, there will inherently be certain characteristics or features in the bearing element. Poles manifest on the formed bearing elements in specific regions. These poles are critical because failure is more common at these locations on the bearing elements. Accordingly, it is desirable to have the ability to identify the location of poles. Known techniques for identifying poles on bearing elements are either destructive or time consuming. For example, one known type of inspection of bearing elements requires boiling the bearing elements in an acid bath, which modifies the surface of the bearing elements. Other analysis methods include scratching the bearing element to create a known modification in residual stress at a specific location, which can then be used to aid in creating a residual stress map.
Accordingly, there is a need to provide a reliable and non-destructive technique for identifying the pole locations on bearing elements.

Method of locating poles on bearing elements


According to example embodiments, a semiconductor light emitting device includes a first semiconductor layer, a pit enlarging layer on the first semiconductor layer, an active layer on the pit enlarging layer, a hole injection layer, and a second semiconductor layer on the hole injection layer. The first semiconductor layer is doped a first conductive type. An upper surface of the pit enlarging layer and side surfaces of the active layer define pits having sloped surfaces on the dislocations. The pits are reverse pyramidal spaces. The hole injection layer is on a top surface of the active layer and the sloped surfaces of the pits. The second semiconductor layer doped a second conductive type that is different than the first conductive type.

1. Field
The present disclosure relates to a semiconductor light emitting device and/or a method of fabricating the same, and more particularly, to a semiconductor light emitting device of which luminescence efficiency is improved by increasing hole injection to an active layer by using a hole injection layer and/or a method of fabricating the same.
2. Description of Related Art
A semiconductor light emitting device (LED), for example, a LED using a Group III-V compound semiconductor such as gallium nitride (GaN), has received a lot of attention in various fields including illumination engineering and display devices due to its superior efficiency for converting electric energy into light, compared to an incandescent light or a fluorescent light. In illumination engineering fields, a white light emitting device may be used. Currently, a white light may be formed by combining a phosphor with a blue light emitting device.
In such white light emitting devices, luminescence efficiency may be an important factor for evaluating the converted light energy against supplied electric energy. Generally, luminescence efficiency may significantly deteriorate as a current increases in a blue light emitting device. The phenomenon is referred to as efficiency droop. Various research is currently being made to address the efficiency droop.
Efficiency droop of a blue light emitting device may occur due to various causes. For example, known causes for efficiency droop include high defect densities due to a lattice mismatch between GaN and a substrate, relatively low mobility of holes, and overflow of electrons. Particularly, in a multiple quantum well (MQW) structure including a plurality of quantum wells (e.g., from 5 to 10), light may be mainly emitted only at quantum wells close to p-GaN due to low mobility of holes.

Semiconductor light emitting device including hole injection layer


Vertical gate all around (VGAA) devices and methods of manufacture thereof are described. A method for manufacturing a VGAA device includes: forming a first doped region having a first conductivity in a substrate; forming a second doped region having a second conductivity different from the first conductivity in the substrate, the second doped region disposed laterally adjacent to and spaced apart from the first doped region; and oxidizing a semiconductive layer disposed between the substrate and the second doped region to form an oxidized isolation layer.

As the semiconductor industry has progressed into nanometer technology nodes in pursuit of higher device density, higher performance, and lower costs, challenges from both fabrication and design issues have resulted in the development of three-dimensional designs, such as a vertical gate all around (VGAA) transistor. A typical VGAA transistor enables enhanced control of the charge carriers along the lengthwise direction through a complete encirclement of the channel region of a semiconductor nanowire by a gate dielectric and a gate electrode. The VGAA transistor has a reduced short channel effect (e.g. compared to a planar transistor), because the channel region may be surrounded by the gate electrode so that an effect of the source/drain region on an electric field of the channel region may be reduced (e.g. relative to a planar transistor).
However, there are challenges to manufacturing a VGAA transistor. For example, the processes and methods utilized in complementary metal-oxide-semiconductor (CMOS) fabrication may not be specifically tailored for the manufacture of VGAA transistors. As such, improvements are needed in the manufacturing processes in order to manufacture VGAA transistors.

Vertical gate all around (VGAA) devices and methods of manufacturing the same

Taiwan Semiconductor Manufacturing Company, Ltd.


A kit for assembling a backrest on a saddle-type vehicle seat selectively connected to the frame and including at least one seat passage extending therethrough. A mounting plate is adapted to be disposed between the seat and the frame. An adapter, adapted to be connected to the mounting plate or integrally formed therewith, includes at least one adapter passage having an open end facing away from the mounting plate. An inverted U-shaped seat mount includes two posts and a connection member connected between their respective first end portions. A second end portion is adapted to be selectively received in the at least one adapter passage through the open end thereof. A back support is adapted to be pivotally connected to the seat mount. At least one fastener for attaching the mounting plate to the seat. Methods for assembling the backrest onto the seat are disclosed.

Straddle seats are provided on many different kinds of vehicles, such as motorcycles, snowmobiles and three-wheeled vehicles. Straddle-seat vehicles may be used for touring purposes where the driver and one or more passengers remain seated on the vehicle for long periods of time. Other uses of straddle-seat vehicles may place more emphasis on maximizing performance from the vehicle and/or driver.
A backrest is sometimes included on a straddle-seat to increase the comfort of the driver and passengers. It is desirable to make the vehicle comfortable for different users and for different usage modes. Some drivers may like to change the configuration of the backrest for different uses of the vehicle. Some drivers may, for example, prefer not to have a backrest while others may prefer to have it be disposed at a certain angle with respect to the seat. It would also be desirable to have the ability to add a backrest to a straddle-seat after the vehicle not provided with a backrest has been purchased.
There is thus a need for a versatile, adjustable and removable backrest. It is desirable to have a backrest for a straddle seat that is comfortable in use, as well as easy to install and adjust according to the preferences of a driver and/or passenger.


A technique for estimating distances and the nature of irregularities and faults on a telephone subscriber line is disclosed. Reflected test signals are measured as a function of frequency. The measurements are compensated for variable propagation velocity and variable line attenuation and then weighted before transformation with the Fourier transform. The amplitude and phase of peaks in the spectral domain identify the distances to the irregularities and the magnitude and phase angle of the reflection coefficients.

With the widespread deployment DSL (Digital Subscriber Line) transmission for Internet access, there is considerable interest in qualifying candidate telephone lines for high-speed digital transmission. A telephone line is known in the industry as a subscriber loop and it connects a telephone customer to a local switching center known as a central office (CO). The subscriber loop is typically composed of 26 gauge cable but it may contain sections of 24 or 22 gauge cable when there is need to avoid excessive attenuation of the voice signal. Operating practices of telephone service providers have typically resulted in one or more bridge taps near the customer end of the subscriber loop. These bridge taps are open circuit stubs (branches) connected in parallel with the main transmission line and their purpose is to provide flexibility for adding and removing station sets as service demand changes. Bridge taps are a significant impediment to high-speed digital transmission.
Another impediment to high-speed digital transmission is the insertion of loading coils. These 88 mH coils are connected in series with the line at regular intervals and reduce voice frequency attenuation by almost one-half. Loading coils are found on subscriber lines that are longer than about 4 km. These coils, together with the capacitance of the transmission line, form a low pass filter that eliminates the higher frequencies required for high-speed digital transmission.
The maximum transmission range of DSL modems is typically specified at 5.5 km and this would normally allow more than 95% of telephone customers to obtain high-speed Internet access. However, telephone service providers are reluctant to offer high-speed DSL service to customers with loops longer than 4 km since some loop structures may prevent transmission of a satisfactory DSL signal. Consequently, some 30-40% of potential customers (those beyond 4 km) are denied service. Accordingly, there is need to test these long loops to see if they might qualify for future provision of DSL service.
It is desirable to make measurements at the central office or possibly a field cabinet where several hundred -lines are connected to trunk cables. From these measurements it is possible to estimate the structure of a subscriber loop and, based on the estimated loop configuration, it is then possible to estimate the DSL transmission characteristics. It is particularly desirable to conduct these measurements using a single-ended approach at the central office so that the tests can be automated.
One single-ended test method uses a time domain reflectometer (TDR) instrument. A pulse is transmitted and the composition of the loop is estimated using identifiable characteristics in the echo response of the loop. This is a well-established method and there are several commercial test instruments based on this method. A problem with this method is the reduced resolution at long distances caused by spreading of the echo pulses A second single-ended method, and the subject of our invention, measures the return signal over a wide range of transmitted sinusoidal frequencies. This approach is generally referred to as the frequency domain or swept-frequency approach and our instrument will be henceforward referred to as a wideband frequency domain reflectometer (W-FDR). One advantage of the W-FDR method is improved resolution and the ability to discern structural discontinuities that are closely spaced.
Reference is made to the following prior art documents which show arrangements which are relevant to the methods Claimed herein, the disclosures of which are all incorporated herein by reference:
G. J. Erker, D. E. Dodds and W. Krzymien, 1995. "ISDN Loop Extension using a Mid-Span Amplifier", International Journal of Communication Systems, May-June, Vol. 8, No. 3, pp. 219-224.
U.S. Pat. No. 3,751,606 (Kaiser) issued Aug. 7th 1973, U.S. Pat. No. 3,904,830 (Peoples) issued Sep. 9th 1975 and pending U.S. application 2002/0146095 (Peoples) published Oct. 10th 2002 all assigned to Bell Telephone Labs in which faults are detected by a frequency-domain detection system.
Also in pending U.S. patent application 2004/0062361 (Kamali et al) published Apr. 1st 2004 is disclosed further developments of this same technique.
These patents thus show a method including the following steps:
inputting into one end of the transmission line a sinusoidal signal varied over a range of frequencies;
separating a reflected return signal from the transmitted signal;
and measuring the portion of the reflected signal that is in-phase with the transmitted signal as a function-of frequency applied at said one end to form a "trace",
and where the Fourier transform is used to generate a spectral analysis of the measured in-phase return signal versus frequency;
and where distances to the irregularities are estimated from the spectral position of peaks in the spectral analysis.

Wideband frequency domain reflectometry to determine the nature and location of subscriber line faults


An apparatus and method is provided to facilitate Input/Output (I/O) transfer in resource limited storage environment. Scatter gather list, segment and memory data buffer allocation are dynamically managed. I/O transfer performance is increased through the use of a data cut-through buffer mechanism.

Typically blocks of memory (data buffers) are pre-allocated for transferring data between applications. The data can be gathered from, or scattered into, a set of data buffers with the pre-allocated set of data buffers being identified through the use of a Scatter-Gather List (SGL). Each entry in the SGL is capable of storing an Address-Length (A/L) pair that identifies a data buffer. A start address for a data buffer is stored in an address field (A) of the A/L pair and the length of the data buffer is stored in a length field (L) of the (A/L) pair typically by application software or device drivers in an operating system.
Typically, all of the memory resources required for an Input/Output (I/O) transfer are allocated before the I/O transfer starts. An I/O transfer refers to a movement of data between data buffers in system memory and a device. In an environment with limited memory resources, such as embedded systems having programs stored in non-volatile memory such as Read Only Memory (ROM) or flash memory, instead of sending all of the data for the I/O transfer in a large single I/O transfer, the data to be transferred may be split up into a plurality of small I/O transfers with the plurality of I/O transfers being performed in linear order. However, splitting the large I/O transfer into a set of smaller I/O transfers reduces overall performance of the large I/O transfer due to the additional overhead required to set up the smaller I/O transfers.
For I/O transfers between initiators and targets in a storage environment, each target includes a queue for storing pending tasks that include I/O transfers. The initiator monitors 'queue depth' information provided by the target to determine if the target can accept a new task. For example, in a system in which each task includes one I/O transfer, a target with a queue depth of 8 is capable of currently processing 8 different I/O transfers. If a large I/O transfer is split into a plurality of smaller I/O transfers, optimal resource utilization is not provided because all of the target's resources for I/O transfers may be used for the single large I/O transfer having the many smaller I/O transfers instead of different I/O transfers.
To increase resource utilization, instead of splitting a large I/O transfer into a plurality of smaller I/O transfers, I/O processing for the large I/O transfer is stalled until a resource is released. When the released resource is allocated to the I/O transfer, the I/O transfer is resumed. Although this method does not have the additional overhead to set up many-small-I/O transfers, however, performance is reduced because stalling I/O transfers requires additional Central Processing Unit (CPU) processing cycles.
Also, when an I/O transfer is stalled, the progress of other I/O transfers may be blocked. For example, the blocked I/O transfers may have a resource/buffer available for use by another I/O but because they are blocked they are unable to release the resource/buffer. Blocked I/O transfers typically occur in applications involving serial storage protocols because of the flow control nature of serial storage protocols.
Although the following Detailed Description will proceed with reference being made to illustrative embodiments of the claimed subject matter, many alternatives, modifications, and variations thereof will be apparent to those skilled in the art. Accordingly, it is intended that the claimed subject matter be viewed broadly, and be defined only as set forth in the accompanying claims.

Data buffer management in a resource limited environment