A reservoir for an ink supply for an ink-jet printer is provided with a refill port through which it can be refilled. The reservoir may be coupled to a variable volume chamber via a check valve which allows the flow of ink from the reservoir to the chamber and limits the flow of ink from the chamber to the reservoir. The chamber is coupled to a fluid outlet which is normally closed to prevent the flow of ink. However, when the ink supply is installed in a printer, the fluid outlet establishes a fluid connection between the chamber and the printer. The chamber is part of a pump provided with the ink supply that can be actuated to supply ink from the reservoir to the printer. Alternatively, the reservoir may be coupled directly to the fluid outlet and an alternative method of transferring the ink to the printer provided.

1. Field of the Invention
The present invention relates to ink supplies for an ink-jet printer and, more particularly to ink supplies that can be readily refilled or replenished.
2. Description of Related Art
A typical ink-jet printer has a print head mounted to a carriage which is moved back and forth over a printing surface, such as a piece of paper. As the print head passes over appropriate locations on the printing surface, a control system activates ink jets on the print head to eject, or jet, ink drops onto the printing surface and form desired images and characters.
To work properly, such printers must have a reliable supply of ink for the print head. Many ink-jet printers use a disposable ink pen that can be mounted to the carriage. Such an ink pen typically includes, in addition to the print head, a reservoir containing a supply of ink. The ink pen also typically includes pressure regulating mechanisms to maintain the ink supply at an appropriate pressure for use by the print head. When the ink supply is exhausted, the ink pen is disposed of and a new ink pen is installed. This system provides an easy, user friendly way of providing an ink supply for an ink-jet printer.
Other types of ink-jet printers use ink supplies that are separate from the print head and are not mounted to the carriage. Such ink supplies, because they are stationary within the printer, are not subject to all of the size limitations of an ink supply that is moved with the carriage. Some printers with stationary ink supplies have a refillable ink reservoir built into the printer. Ink is supplied from the reservoir to the print head through a tube which trails from the print head. Alternatively, the print head can include a small ink reservoir that is periodically replenished by moving the print head to a filling station at the stationary, built-in reservoir. In either alternative, ink may be supplied from the reservoir to the print head by either a pump within the printer or by gravity flow.
Still other ink-jet printers use replaceable reservoirs that are separate from the print head. These reservoirs, like the built-in reservoirs are not located on the carriage and, thus, are not moved with the print head during printing. Replaceable reservoirs are often plastic bags filled with ink. The bag is provided with a mechanism, such as a septum which can be punctured by a hollow needle, for coupling it to the printer so that ink may flow from the bag to the print head. Often, the bag is squeezed, or pressurized in some other manner, to cause the ink to flow from the reservoir.
Once depleted, the reservoir is typically discarded and a new reservoir installed. However, the reservoir and any associated mechanisms are typically capable of further use if they could be replenished with a fresh supply of ink.


Methods and apparatus are adapted to wash magnetic particles isolated in a vessel. The methods include providing a vessel with wash liquid and a layer of magnetic particles, providing a probe having aspiration capability, positioning a probe tip above the layer of magnetic particles, aspirating at least some of the wash liquid above the layer, positioning the probe tip below the layer, and aspirating at least some of the wash liquid from below the layer of magnetic particles. The suction may be turned off as the probe tip descends past the layer. A novel magnetic particle washing apparatus are disclosed.

In medical testing and processing, the use of robotics may minimize exposure to, or contact with, bodily fluid samples (otherwise referred to as "specimens") and/or may significantly increase productivity. For example, in some automated testing and processing systems (e.g., clinical analyzers), a specimen and/or reagent liquid may be aspirated from one liquid-containing vessel (e.g., a sample collection tube or reagent container) and may be transferred to another liquid-containing vessel (e.g., a reaction cuvette).
Such liquid transfer may be accomplished by the use of a robot, which may include a suitable moveable robotic component, an aspirating and dispensing apparatus, and an attached probe. The probe may be moved in one or more coordinate directions by the robot. In this manner, the probe may aspirate a specimen or reagent liquid from a first liquid-containing vessel, and then move and dispense the specimen or reagent liquid into another liquid-containing vessel.
In some medical diagnostic testing, magnetic particles may be introduced into the liquid-containing vessel (e.g., a cuvette) and during a reaction, a chemical constituent or component of interest (e.g., an analyte) may bind to active surfaces of the magnetic particles. After the reaction, the magnetic particles may undergo an automated wash process. The wash process is intended to remove any remaining contaminated liquids and/or other contaminants and leave behind just the magnetic particles with the chemical constituent or component of interest bound thereto. Prior to the wash process, the magnetic particles may be drawn to a side of the liquid-containing vessel (e.g., a cuvette), such as by a magnet.
In existing wash processes, some magnetic particles may be inadvertently lost, thereby reducing an amount of the chemical constituent or component of interest remaining to test. Moreover, sometimes, foam, wash liquid and/or other liquid may inadvertently adhere to the walls of the liquid-containing vessel (e.g., a cuvette).
Accordingly, wash methods and apparatus that may improve a thoroughness of a washing of the magnetic particles are desired.

Magnetic particle washing apparatus and method


An image processing device converting a binary image into multi-valued output image includes an image-area-separation processing unit detecting shadow areas in the binary image, wherein the shadow areas are graphic or photographic image areas having a number of lines greater than a predetermined number, an outline-correction processing unit correcting jagged edges in the binary image to generate a corrected image, an multi-value processing unit converting the binary image into a multi-valued image through a filtering process, and a selection unit selecting the multi-valued image for the shadow areas and the corrected image for areas other than the shadow areas so as to generate the multi-valued output image.

1. Field of the Invention
The present invention generally relates to image processing devices, and more particularly relates to an image processing device which converts an input binary image into a multi-valued image.
2. Description of the Related Art
Related art methods which convert a binary image into a multi-valued image include the following techniques, some of which are devised in order to improve quality of an output image.
(a) Konica Ltd., Image Lab. 1933. 3, "TECHNIQUE OF IMAGE RESTORATION FROM BINARY IMAGE INTO HALF-TONE IMAGE" discloses a method in which images to be treated are restricted to photographic (natural) images. PA1 (b) Cannon Ltd., NIP-24, "HIGH-DEFINITION MULTI-VALUED RESTORATION OF BINARY IMAGE USING NEURAL NETWORK" discloses a method which converts a binary image into a multi-valued image while distinguishing line-drawing areas from photographic(natural)-image areas by utilizing a learning capacity of a neural network. PA1 (c) Proceedings of Institute of Engineers of Electronics and Communication, Vol.J68-D, No.6, 1985, "SMOOTHING PROCESSING AND EDGE DETECTION OF DITHER IMAGE" discloses a method which detects edges and changes an aperture size of a smoothing filter used for creating a multi-valued image. PA1 (d) Proceedings of Image Electronics Conference, No.19, 1991, "METHOD OF RESTORING MULTI-VALUED IMAGE FROM BINARY IMAGE BY USING AREA IDENTIFICATION" and PA1 (e) Proceedings of Image Electronics, Vol.22, No.2, 1993, "METHOD OF RESTORING MULTI-VALUED IMAGE FROM BINARY IMAGE BY USING AREA IDENTIFICATION" disclose a method in which different types of image restoration techniques are applied based on results of image-area-separation processing of binary images, which processing identifies concentrated-pseudo-halftones by using dither matrixes. PA1 (f) Japanese Laid-Open Patent Application No.2-112966, titled "IMAGE OUTPUT METHOD AND DEVICE" discloses a method which eliminates jagged edges of letter images or line-drawing images.
Taking an advantage of a limited application to photographic images, the method (a) can demonstrate its effect to some degree. When applied to other types of images, however, the method (a) brings about an image degradation in letter images and line drawings. The method (c) which detects edges and changes the aperture size of the smoothing filter in order to preserve an edge sharpness brings about image degradation as well.
The method (b) which uses the neural network requires huge hardware, which is not desirable, and does not offer a proven effect for an unlearned image.
The methods (d) and (e) require only a small amount of hardware, since they switch the types of image processing based on results of the image-area-separation processing on binary images. However, the use of the dither matrixes for identifying concentrated-pseudo-halftones leads to a poor resolution. Also, there is a problem that erroneous-separation points can be scattered within a particular area. Thus, when the method is used for a printer device, letters or line drawings can be degraded, or photographic image areas can be partly left unchanged to multi-values. These problems make it difficult to use the method for a practical purpose.
The method (f) eliminates jagged edges of letter images or line drawings and can create problems in processing photographs and graphic images.
Accordingly, there is a need in the field of image processing devices for an image processing device which can convert a binary image into a multi-valued image of an improved image quality while eliminating jagged edges of letter images and line drawings.
Also, there is a need in the field of image output devices for an image output device which can convert a binary image into a multi-valued image of an improved image quality while eliminating jagged edges of letter images and line drawings.

Image processing device and image output device converting binary image into multi-valued image


A method of recycling construction and demolition debris produces a product useful in earth engineering applications, including landfills, soil stabilization and roadbeds. The method involves wet shredding construction and demolition debris into a moist shredded product using landfill leachate as the wetting medium and applying the product as daily cover for a landfill. A landfill design using the recycled product is also disclosed.

Federal and state environmental regulations require the operators of sanitary landfill operations to periodically cover disposed solid waste with six inches of earthen material to control disease, insects, fires, odors, blowing litter, and scavenging. For example, most jurisdictions require such covering of sanitary landfills at the end of each operating day, or at more frequent intervals if necessary. This covering requirement and the cover material is known as "daily cover" or "periodic cover" where the regulatory interval is more than one day, e.g., three days. As used herein, "daily cover" is intended to include daily and periodic cover for sanitary landfills, such as municipal solid waste (MSW) landfills, rubble landfills, land clearing debris landfills, and industrial waste landfills.
Each day's garbage, trash or rubble layer is covered at the end of the day and further garbage, trash or rubble layers are then spread directly on top of the daily cover from the previous day. In many landfill sites the soil used for the daily cover must be mined at the landfill site or purchased from an outside source and, due to the high rate of soil consumption, comprises a substantial cost item. Moreover, it has been recognized that multiple earth fill layers used in this way consume a significant volume of the valuable landfill space which might otherwise be used for receiving garbage, trash or rubble. It is well known that many communities are rapidly exhausting their available landfill acreage and it is therefore desirable to reduce the consumption rate of the available landfill volume. Accordingly, federal and state regulations allow alternative, more compressible, daily cover materials in lieu of the six inches of earthen material so long as the alternative materials provide the requisite level of protection.
One known solution to reducing the volume of municipal solid waste landfills is to shred the municipal solid waste to achieve a greater filling density in the landfill. One example of this solution is disclosed in U.S. Pat. No. 4,834,300 to Wojciechowski et al. which describes a process of reducing municipal solid waste to dry particles of a relatively small, uniform size to be mixed with the earth of a landfill for minimizing settlement and maximizing the load support capabilities of the landfill. While this process for forming a municipal solid waste landfill may be acceptable in some jurisdictions, it does not provide the daily cover required by the great majority of jurisdictions.
Some jurisdictions permit disposal of municipal solid waste in a landfill in shredded form without a requirement for daily cover. Although this method for disposal is accepted in some instances, it still has serious health and environmental drawbacks compared to landfills which require daily cover.
The prior art also does not adequately address the problem of disposing of construction and demolition debris in an efficient, useful and/or space saving manner. Rubble landfills in which construction and demolition debris is typically disposed consume a substantial volume of available landfill space. It would be desirable therefore to provide a method of recycling construction and demolition debris in a way which eliminates the need for rubble landfills and in which substantially the entire volume of construction and demolition debris can be recycled and made use of in other earth engineering applications.
Another problem not adequately addressed by the prior art is the disposal of the leachate that collects at the bottom of a landfill. At the present time, such leachate must be transported or pumped to a facility for treatment of any odiferous, toxic, hazardous and/or other wastes that may be contained in the leachate. The cost of such leachate treatment, necessarily adds to the cost of operating a landfill. It would be desirable therefore to provide a method of disposing of or recycling the landfill leachate in such a way as to minimize or eliminate the cost of treating and/or disposing of the leachate.

Method of recycling construction and demolition debris


An efficient navigator method is presented that substantially increases the scan efficiency while maintaining the motion suppression effectiveness in magnetic resonance imaging. The method is achieved by simultaneously acquiring different image volumes at different motion states of the subject being scanned. A scheduling algorithm is used to assign volumes to position bins of a motion histogram of the subject. The motion histogram is periodically updated and the volumes are reassigned to position bins.

Magnetic resonance imaging (MRI) is the method of choice for noninvasive diagnosis of soft tissue disease in humans, and has wide applications in cardiovascular diseases. Fast gradient technology has made high-resolution 3D imaging possible, including magnetic resonance angiography (MRA) of coronary and pulmonary arteries. However, the acquisition time for high quality, high resolution data is on the order of minutes. Artifacts from physiological motion occurring during data acquisition, such as respiration and cardiac contraction, degrade image quality and result in blurring or ghosting.
Industry responded by developing methods to suppress the artifacts caused by physiological motion. One suppression approach is the real-time navigator method, which monitors respiration and controls data acquisition accordingly in real-time. Most current navigator techniques are based on gating and they reconstruct images only using data acquired when motion is in a specified window. In these navigator techniques, a motion tolerance window (e.g., gating window) is specified and only the data that is within the specified window is used to construct images. Effective motion suppression requires a small gating window that leads to a long scan time, resulting in inefficiencies. Typically, a single image volume at a window near the most likely motion position, as indicated by the peak of the subject's motion histogram, is taken as represented in FIG. 9. Currently, one of the most efficient methods available is the phase ordering with automatic window selection method (i.e. PAWS), which is optimized against variation in the subject's respiration pattern. In the PAWS method, a fraction of the total scan time corresponding to a small gating window is used for image acquisition. Data at other motion levels are not useable. As a result, scan time is wasted when the subject's position is outside the gating window.

Motion organized simultaneous acquisition with interactive control for fast real-time navigator guided imaging


The present invention provides methods for inhibiting hyperlipemia which is responsible for various diseases such as arteriosclerosis, which comprise administering to a subject emmeisou or an emmeisou extract.

The eating habits of people in developed countries have become richer along with economical development, and fat-intake has gradually increased. However, an excessive fat-intake destroys the balance of the amount of lipids in the blood and causes hyperlipemia. In the present specification, "hyperlipemia" describes conditions in which one or more cholesterols, triglycerides, lipoproteins and/or phospholipids that are lipid components in serum are at an increased level, i.e., it means hypercholesterolemia, hypertriglyceridemia, etc. There is an intimate correlation between hyperlipemia and adult diseases of the circulatory system such as arteriosclerosis. Nowadays, many people suffer from these diseases and it has become a social problem.
At present, drugs such as clofibrate, probucol or nicotinic acid are used as a medicament for treating hyperlipemia, but all of these drugs have side effects. Accordingly, a new medicament is required which exhibits less side effects and is safer to use.
The problem addressed by the present invention was to provide a food composition and a pharmaceutical composition for inhibiting hyperlipemia which is responsible for various diseases such as arteriosclerosis, said compositions being very safe to use and having excellent effects.

Method for inhibiting hyperlipemia with emmeisou or an extract thereof


To control access to target data whilst relieving the data provider of policing obligations, the data provider provides the target data in encrypted form to a requesting party as part of a data set with which first and second trusted authorities are associated in a non-subvertible manner. Recovery of the target data in clear by the party requires the first trusted authority to verify that a specific individual is a professional accredited with it, the second trusted authority to verify that a particular organisation is accredited with it, the particular organisation to verify that the specific individual is engaged by it, and at least one of the particular organisation and the first trusted authority to verify that the party is the specific individual. Various ways of encrypting the target data are provided, the preferred ways being based on Identifier-Based Encryption schemas.

Professionals working in the same field frequently belong to a professional body one role of which may be to maintain a list of accredited professionals working in the field concerned (though not necessarily members of the body); such a role may, indeed, have regulatory force. Entry on the list of accredited professionals often requires an individual to have obtained certain qualifications but will generally also require that the individual has not committed any major act detrimental to their clients. Thus the accredited status of a professional is not something which once obtained will necessarily continue.
One field where the professional status of an individual is of particular importance is the medical field. This field places high demands not only on the skill of the individuals concerned but also on maintaining the confidentiality of patient records. It is expected that electronic medical records of patients will replace paper records in the near future. The update of these records is likely to be the responsibility of the patient's local doctor (that is, their "general practitioner" or "GP"). The GP, for the purpose of secure preservation of patient data, is likely to use a secure data storage service to store the electronic patient records. In an emergency situation, in which a patient requires medical care, an attending doctor or paramedic (generally, a medical professional) needs to know, as a matter of urgency, the medical history of the patient to prevent giving inappropriate treatments. There is therefore a need for the attending medical professional to obtain the patient's medical records from the data storage service provider; however, this needs to be done in a manner that safeguards the privacy of the records.
Most solutions that have been proposed for dealing with the above situation involve the use of a public key infrastructure (PKI) which would need to be created for the medical professionals. In such a PKI, a professional body for medical professionals would act as a certificate authority providing an accredited medical professional with a certificate confirming their accreditation and public key. In an emergency situation, the medical professional would send a patient identifier together with the professional's own certificate to the patient data storage service. This service would verify the validity of the certificate, encrypt the patient's records with the medical professional's public key, and return the encrypted data to the medical professional.
One disadvantage of the foregoing arrangement is that it does not distinguish between a request from a medical professional carrying out their work in a hospital emergency room and a medical professional who just wants to pry into the details of a patient. Another disadvantage is the need for the data storage service to keep, or have immediate access to, an up-to-date certificate revocation list.
It is an object of the present invention to provide an improved way for professionals to access confidential data in a controlled manner that obviates at least some of the problems associated with prior systems. It is to be understood that the present invention is not limited to the provision of sensitive data to medical professionals but is applicable to all types of professionals.
As will explained hereinafter, the preferred embodiments of the invention utilise Identifier-Based Encryption (IBE) which is an emerging cryptographic schema. For convenience, this known schema will next be described with reference to FIG. 1 of the accompanying drawings. In FIG. 1 a data provider 10 is shown as encrypting payload data 13 using both an encryption key string 14, and public data 15 provided by a trusted authority12. This public data 15 is related to private data held by the trusted authority; for example, the public data is derived by the trusted authority 12 from private data 17 using a one-way function 18. The data provider 10 then provides the encrypted payload data <13> to a recipient 11 who decrypts it, or has it decrypted, using a decryption key computed by the trusted authority 12 in dependence on the encryption key string and its own private data.
A feature of identifier-based encryption is that because the decryption key is generated from the encryption key string, its generation can be postponed until needed for decryption.
Another feature of identifier-based encryption is that the encryption key string is cryptographically unconstrained and can be any kind of string, that is, any ordered series of bits whether derived from a character string, a serialized image bit map, a digitized sound signal, or any other data source. The string may be made up of more than one component and may be formed by data already subject to upstream processing. In order to avoid cryptographic attacks based on judicious selection of a key string to reveal information about the encryption process, as part of the encryption process the encryption key string is passed through a one-way function (typically some sort of hash function) thereby making it impossible to choose a cryptographically-prejudicial encryption key string. In applications where defence against such attacks is not important, it would be possible to omit this processing of the string.
Frequently, the encryption key string serves to "identify" the intended message recipient and the trusted authority is arranged to provide the decryption key only to this identified intended recipient. This has given rise to the use of the label "identifier-based" or "identity-based" generally for cryptographic methods of the type under discussion. However, depending on the application to which such a cryptographic method is put, the string may serve a different purpose to that of identifying the intended recipient and may be used to convey other information to the trusted authority or, indeed, may be an arbitrary string having no other purpose than to form the basis of the cryptographic processes. Accordingly, the use of the term "identifier-based" or "IBE" herein in relation to cryptographic methods and systems is to be understood simply as implying that the methods and systems are based on the use of a cryptographically unconstrained string whether or not the string serves to identify the intended recipient. Generally, in the present specification, the term "encryption key string" or "EKS" is used rather than "identity string" or "identifier string"; the term "encryption key string" is also used in the shortened form "encryption key" for reasons of brevity.
A number of IBE algorithms are known and FIG. 2 indicates, for three such algorithms, the following features, namely:                the form of the encryption parameters 5 used, that is, the encryption key string and the public data of the trusted authority (TA);        the conversion process 6 applied to the encryption key string to prevent attacks based on judicious selection of this string;        the primary encryption computation 7 effected;        the form of the encrypted output 8.
The three prior art IBE algorithms to which FIG. 2 relates are:                Quadratic Residuosity (QR) method as described in the paper: C. Cocks, "An identity based encryption scheme based on quadratic residues", Proceedings of the 8th IMA International Conference on Cryptography and Coding, LNCS 2260, pp 360-363, Springer-Verlag, 2001. A brief description of this form of IBE is given hereinafter.        Bilinear Mappings p using, for example, a modified Tate pairing t or modified Weil pairing e for which:p: G1×G1→G2 where G1 and G2 denote two algebraic groups of prime order q and G2 is a subgroup of a multiplicative group of a finite field. For the Tate pairing an asymmetric form is also possible:p: G1×G0→G2 where G0 is a further algebraic group the elements of which are not restricted to being of order q. Generally, the elements of the groups G0 and G1 are points on an elliptic curve though this is not necessarily the case. A description of this form of IBE method, using modified Weil pairings is given in the paper: D. Boneh, M. Franklin—"Identity-based Encryption from the Weil Pairing" in Advances in Cryptology-CRYPTO 2001, LNCS 2139, pp. 213-229, Springer-Verlag, 2001.        RSA-Based methods The RSA public key cryptographic method is well known and in its basic form is a two-party method in which a first party generates a public/private key pair and a second party uses the first party's public key to encrypt messages for sending to the first party, the latter then using its private key to decrypt the messages. A variant of the basic RSA method, known as "mediated RSA", requires the involvement of a security mediator in order for a message recipient to be able to decrypt an encrypted message. An IBE method based on mediated RSA is described in the paper "Identity based encryption using mediated RSA", D. Boneh, X. Ding and G. Tsudik, 3rd Workshop on Information Security Application, Jeju Island, Korea, August, 2002.
In all of the above cases, the decryption key is generated by a trusted authority in dependence on the encryption key string.
A more detailed description of the QR method is given below with reference to the entities depicted in FIG. 1 and using the same notation as given for this method in FIG. 2. In the QR method, the trust authority's public data 15 comprises a value N that is a product of two random prime numbers p and q, where the values of p and q are the private data 17 of the trust authority 12. The values of p and q should ideally be in the range of 2511 and 2512 and should both satisfy the equation: p,q≡3 mod 4. However, p and q must not have the same value. Also provided is a hash function # which when applied to a string returns a value in the range 0 to N−1.
Each bit of the user's payload data 13 is then encrypted as follows:                The data provider 10 generates random numbers t+ (where t+ is an integer in the range [0, 2N]) until a value of t+ is found that satisfies the equation jacobi(t+,N)=m′, where m′ has a value of −1 or 1 depending on whether the corresponding bit of the user's data is 0 or 1 respectively. (As is well known, the jacobi function is such that where x2≡#mod N the jacobi (#, N)=−1 if x does not exist, and =1 if x does exist). The data provider 10 then computes the value:s+≡(t++K/t+)modN        where: s+ corresponds to the encrypted value of the bit m′ concerned, and        K=#(encryption key string)        Since K may be non-square, the data provider additionally generates additional random numbers t− (integers in the range [0, 2N)) until one is found that satisfies the equation jacobi(t−, N)=m′. The data provider 10 then computes the value:s−≡(t−−K/t−)modN         as the encrypted value of the bit m concerned.
The encrypted values s+ and s− for each bit m′ of the user's data are then made available to the intended recipient 11, for example via e-mail or by being placed in a electronic public area; the identity of the trust authority 12 and the encryption key string 14 will generally also be made available in the same way.
The encryption key string 14 is passed to the trust authority 12 by any suitable means; for example, the recipient 11 may pass it to the trust authority or some other route is used—indeed, the trust authority may have initially provided the encryption key string. The trust authority 12 determines the associated private key B by solving the equation:B2≡K modN ("positive" solution)
If a value of B does not exist, then there is a value of B that is satisfied by the equation:B2≡−K modN ("negative" solution)
As N is a product of two prime numbers p, q it would be extremely difficult for any one to calculate the decryption key B with only knowledge of the encryption key string and N. However, as the trust authority 12 has knowledge of p and q (i.e. two prime numbers) it is relatively straightforward for the trust authority 12 to calculate B.
Any change to the encryption key string 14 will result in a decryption key 16 that will not decrypt the payload data 13 correctly. Therefore, the intended recipient 11 cannot alter the encryption key string before supplying it to the trust authority 12.
The trust authority 12 sends the decryption key to the data recipient 11 along with an indication of whether this is the "positive" or "negative" solution for B.
If the "positive" solution for the decryption key has been provided, the recipient 11 can now recover each bit m′ of the payload data 13 using:m′=jacobi(s++2B,N)
If the "negative" solution for the decryption key B has been provided, the recipient 11 recovers each bit m′ using:m′=jacobi(s−+2B,N)

Secure data provision method and apparatus and data recovery method and system

Hewlett-Packard Development Company, L.P.


There is provided a mobile wireless terminal permitting the distance between the antenna and the human head can be kept relatively constant even if the angle formed by the case of the apparatus is varied, making it possible to ensure stable antenna performance.

1. Field of the Invention
The present invention relates to a mobile wireless terminal having an antenna device extensible from the case of the mobile wireless terminal and, more particularly, to an improvement for preventing the antenna performance from deterioration.
2. Description of the Prior Art
A mobile wireless terminal capable of mobile communication is usually susceptible to wide fluctuations of the situation of electromagnetic waves during transit, and requires stable antenna performance in order to ensure stable wireless characteristics. Especially in communication taking place close to a human body, as the antenna is very close to the human head which is apt to inflict loss, the antenna performance may be greatly deteriorated by the human head, and in a state in which the antenna is stowed, the antenna is closer to the human head than when it is extended, and accordingly its performance is even more susceptible to deterioration by the head.
Furthermore, as the angle formed by the case of the mobile wireless terminal and the human head varies during communication, the antenna sometimes approaches and at other times moves away from the human head with a destabilizing effect on the antenna performance.
FIG. 1 and FIG. 2 show front views of a mobile wireless terminal according to the prior art in some of the ways it is used during a call. In the drawings, the conventional mobile wireless terminal is provided with an upper case 100 having a receiver section 104 and a lower case 101, and the two cases are rotatably connected by a hinge section 103. The upper case 100 accommodates an extensible antenna, which can be drawn out of the case, and its tip section 105 projects from the upper end of the upper case 100. The antenna tip section 105 has an antenna coil section inside. A tangent 120 in FIG. 1 and FIG. 2 is the tangent of contact between the upper case 100 of the mobile wireless terminal and a human face (cheek), and a line 121 is the central axis of the antenna.
According to the prior art, when the inner face (the face that is inside when the terminal is folded) of the upper case 100 is in contact with the user's cheek as shown in FIG. 1, the antenna tip section 105 is at a distance B from the human head.
However, when the case is rotated round the upper end 106 of the upper case 100 on the side in contact with the cheek and the inner face of the upper case 100 moves away from the cheek as shown in FIG. 2, the distance (D<B) between the antenna tip section 105 and the human head varies in the direction of bringing the cheek closer to the tip section of the antenna, resulting in substantial variations in the impedance characteristic and the radiation characteristic of the antenna.

Abstract: A mobile wireless terminal according to the invention is fitted to an upper case and has an antenna extensible from the upper case and, when that antenna is stowed in the upper case 1, the upper end of the upper case protrudes farther than the position of an ½ length of a coil section, which is the tip section of an antenna element positioned at the tip section of the antenna.


When making a characteristic line, a plurality of different small amount reference light beams is caused to impinge upon the photodetector element, a zero-light signal value is obtained by extrapolation of the relation between the small amount side reference light beams and the signal values which are respectively output from the photodetector element in response to the small amount side reference light beams, a large amount reference light signal value which is output when a large amount light beam impinges upon the photodetector element is obtained, and a characteristic line representing a relation between the amount of light which the photodetector element receives and a value of the signal which is output from the photodetector element is made on the basis of the zero-light signal value and the large amount reference light signal value.

1. Field of the Invention
This invention relates to a method of making a characteristic line, and more particularly to a method of making a characteristic line representing the relation between a signal value of a photodetector element which outputs a signal of a value depending upon the amount of light which it receives and the amount of light which the photodetector element receives.
2. Description of the Related Art
When a photodetector element which outputs a signal of a value depending upon the amount of light which it receives is used, there has been known a system where a characteristic line representing the relation between a signal value of the photodetector element and the amount of light which it receives is obtained and the amount of light which the photodetector element receives is obtained from the signal value output from the photodetector element on the basis of the characteristic line. (See Japanese Unexamined Patent Publication No. 2001-137175)
As a procedure for obtaining the characteristic line, there has been known, for instance, that where a value of a signal output from a photodetector element with the photodetector element receiving no light and at the same time while a value of a signal output from the photodetector element with the photodetector element receiving an amount of light near to a maximum which the photodetector element can receive is obtained, and the characteristic line is obtained on the basis of the relation between the amount of light which the photodetector element receives and the output of the photodetector element of each of the pairs of amount of light and the output. That is, in the procedure, the signal value output from the photodetector element is converted to a light amount by the use of the characteristic line.
When such a characteristic line is applied to a line sensor in which a number of photodetector elements are arranged in one direction, there has been known a method in which the characteristic line is obtained element to element and the signal values output from the respective photodetector elements are weighted so that they output the same signal values when they receive the same amount of light.
However, in the photodetector element, the relation between the amount of light which the photodetector element receives and the output of the photodetector element is slightly nonlinear on the side where the amount of light which the photodetector element receives is small. Accordingly, there has been a demand to obtain a more accurate amount of light even on the side of small amount of light.
To the contrast, a method where relations of a plurality of pairs of amount of light and the signal value are obtained and stored in a look-up table on the side of small amount of light and the signal value exhibiting the amount of light which the photodetector element actually receives is obtained without use of the characteristic line by interpolation between points on a two-dimensional coordinate system representing a relation between the amount of light which the photodetector element receives and the signal value (one axis representing the amount of light and the other axis representing the signal value) on the basis of the look-up table is conceivable.
However, the method using the look-up table is disadvantageous in that the system is complicated since the look-up table must be referred to every time the amount of light which the photodetector element receives (will be referred to as "the photodetector receiving light amount", hereinbelow) is obtained. Further, attempt to apply the method to a line sensor will further complicate the system and the problem will become more serious since the look-up tables must be prepared for all the photodetectors forming the line sensor.
Accordingly, it is required to make more accurate the relation between the photodetector receiving light amount and the signal value on the side of small amount of light while using the characteristic line.


A bamboo drum has a hollow cylinder formed of a plurality of ring bodies stacked together. The ring bodies are made of bamboo sheets and provided respectively along the upper ring portion thereof with a protruded circular rib, a circular groove, and an inclined circular surface for enabling the ring bodies to be stacked together to form the hollow cylinder without voids. Each of the ring bodies has two end portions of various forms to provide the two end portions with the contact areas capable of fusing securely the two end portions of the ring body.

As shown in FIG. 1, a wooden drum 10 of the prior art is made of a plurality of layers of thin wooden sheets 11. The thin wooden sheets 11 are generally made of the discarded wood. There are often voids that are present between layers of the wooden sheets 11. It is technically difficult to avoid the formation of voids when the wooden drum 10 is made. The poor quality of the thin wooden sheets 11 and the voids can prevent the drum 10 from producing good quality sound.


The invention provides a data visualisation system comprising a data value memory in which is maintained a finite set of data values obtained from monitoring apparatus and a display configured to display a representation of each data value centered on respective data points. The invention also provides a contour generator which in one form is configured to generate and display a contoured representation around each data point such that each data point is displayed as a local maximum and in another form is configured to generate and display one or more contour lines around each data point, each contour line representing data values which are less than the data value of the data point around which the contour line is displayed. The invention also provides related methods and computer programs.

The low cost of data storage hardware has led to the collection of large volumes of data. Merchants, for example, generate and collect large volumes of data during the course of their business. To compete effectively, it is necessary for a merchant to be able to identify and use information hidden in the collected data. Where the merchant operates retail premises, this data could include operational parameters such as the length of customer queues, the average waiting time in a queue, the average service time and so forth. The data could also include information on the areas in which customers prefer to browse within a retail premises. The task of identifying this hidden information has proved very difficult for merchants.
U.S. Pat. No. 5,097,328 to Boyette describes a system which performs image processing of camera images. The system is designed for use in businesses which include queues or servers and has a camera which captures successive images of an area to be monitored. A combination of blob analysis and motion analysis is used to determine if a server is on duty and present at the server's station, and if the server is serving a customer. Using blob analysis techniques, the system is able to maintain a count of the number of people waiting in the queue to be served. The data is used to generate displays directing waiting customers to the next available server and to inform newly arriving customers of their expected waiting time.
U.S. Pat. No. 5,953,055 to Huang et al/NCR Corporation describes a system for detecting, collecting information about, and analysing a queue. A sequence of video images from a video camera are converted into digital video images and pixel processing and edge detection are performed, regions separated by less than a defined pixel distance are grouped into single objects, and the number of objects are counted to determine the number of persons in an area, for example a queue. The system can collect data on the number of people in the queue, the average service time for each person in the queue, and other types of information regarding the queue.
U.S. Pat. No. 5,864,616 to Hartmeier/Intel Corporation describes a system which collects data on call activity, for example the number of calls waiting in a queue, the time duration of the oldest call still in the queue, and a site identifier. The system displays these statistics to a user in a display which uses features such as colour to indicate the current state of calls waiting to be served and the longest call waiting.
The systems described above are largely focused on the capture and storage of data representing human activity. None of these systems provide a means of display of the captured and stored data in a form which is intuitive and easy to interpret.


A polarization split device that includes an optically isotropic substrate, an optically anisotropic film, and a diffraction grating. The optically anisotropic film is formed on the optically isotropic substrate. The diffraction grating includes first and second cyclically structural portions. The first cyclically structural portion is formed on a front surface of the optically anisotropic film such that a depression in a rectangular shape is cyclically arranged with a predetermined pitch. The second cyclically structural portion includes an optically transparent material having a refractive index approximately equivalent to a refractive index of the optically anisotropic film and is configured to cover the first cyclically structural portion. Diffraction light having a diffraction angle greater than a predetermined angle among diffraction light diffracted by the diffraction grating is inhibited from being discharged outside.

1. Field of the Invention
The present invention relates to a method and apparatus for optical pickup, and more particularly to a method and apparatus for optical pickup that is capable of performing an effective polarization split.
2. Discussion of the Background
As a variety of optical recording media such as a CD (compact disc), a DVD (digital versatile disc), etc. are developed, research and development of suitable optical pickup devices becomes crucial. In general, an optical pickup device for reading to and writing from an optical recording media includes a light source emitting laser light, an optical system including lenses and so on for irradiating an optical recording medium with the laser light emitted from the light source, an optical detection mechanism for detecting reflection laser light reflected by the optical recording medium, and so forth. Such an optical pickup device is typically provided with a polarization split device. The polarization split device allows the laser light directed towards the optical recording medium from the light source to pass entirely therethrough, and causes the laser light to diffract relative to the reflection laser light reflected by the optical recording medium so that the laser light is split. This method uses a light path through which the laser light is caused to travel forward and backward. Such a polarization split device generally includes diffraction gratings having different optical characteristics, e.g., having different transmittance, diffraction efficiency, etc., according to states of a polarization plane of the laser light.
Also, the optical pickup device is generally provided with a quarter-λ plate (also referred to as a quarter frequency plate) at an object lens side of the polarization split device. With this quarter-λ plate, reflected laser light having a polarization direction rotated by 90 degrees is caused to impinge on the polarization split device so that the reflected laser light is guided to a light detecting device.
In recent years, research and development have been increasingly made for a single optical pickup device that is capable of reading from and writing to a plurality of different optical recording media such as a CD (compact disk) and a DVD (digital versatile disk), for example, having different recording densities.
To read from and write to a plurality of different optical recording media, such as a CD and a DVD, for example, having different recording densities with a single optical pickup device, it is necessary to provide the optical pickup device with two laser light sources having different wave lengths.
When a single optical pickup device with two laser light sources having different wave lengths is provided with two different optical systems for the two laser sources, the size of the optical pickup device becomes large, which may be a problem. To avoid this problem, an optical pickup device having two different laser light sources and a single optical system has been developed. In this development, various components used in the two different optical systems are necessarily made into common components.
The above-described polarization split device is one of the components needed to be modified into common components. One example of the polarization split device made as a common component is described in published Japanese unexamined patent application No. JP11-311709, in which a polarization split device is fabricated based on an LN (lithium niobic acid) substrate with an ion-exchange process. In the ion-exchange process, however, splitting of areas depends on dispersion, and therefore it is very difficult to conduct splitting in a perfect manner.
Another example is described in published Japanese unexamined patent application No. JP11-295510, in which a polarization split device is fabricated based on a diacetylene monomer film to which ultraviolet rays are irradiated. In this case, perfect parallel ultraviolet rays are required to carry out splitting of areas. In addition, reflection light rays from the substrate, scattering light, and the like, may degrade allowable operating conditions. Therefore, it may be very difficult to split every uneven portion in an ideal manner.
Another example is described in published Japanese unexamined patent application No. JP11-064615, in which a polarization split device is fabricated such that patterns are formed with a dry etching process in a high polymer liquid crystal film formed on a glass substance and are then charged with a filler having a refractive index that matches the high polymer liquid crystal film. In the dry etching, however, a side etching or a mask recess may cause an adverse effect on the shape of a diffraction grating, and therefore it may be vary difficult to form a diffraction grating in a perfect rectangular shape.
When a diffraction grating formed in an imperfect rectangular shape is used, even-numbered-order diffraction light, which should not be generated from a design point of view, may be generated and cause reduction of efficiency as well as generation of undesired light. As a result, an adverse effect on a light detection may occur. This leads to an erroneous reading and writing of the optical pickup device relative to an optical recording medium.

Method and apparatus for optical pickup capable of performing an effective polarization split


An liquid crystal display (LCD) device uses a method for displaying halftone without causing luminance differences among pixels when an FRC technique is used, and without causing stripe-shaped luminance variations when a flicker component is eliminated spatially. The LCD device includes a data splitter, a pixel location detecting circuit, a frame number determining circuit, an applied timing memory circuit, an applied voltage determining circuit, a summation process circuit, and a timing adjusting circuit. The LCD device determines driving voltages such that for each of a high voltage or a low voltage during these 2N frames, the number of applying positive voltages is the same as the number of applying negative voltages where a unit period is 2N frames for multi-gray-level display of (1+N) levels. The LCD device can improve image quality since the average luminance of each pixel is made uniform.

1. Field of the Invention
The present invention relates generally to a method and an apparatus for displaying halftone in a liquid crystal display. More particularly, the present invention relates to a method and an apparatus for displaying halftone in a liquid crystal display by applying two different voltages periodically.
2. Description of the Related Art
Typically, a liquid crystal display (LCD) device contains a display panel in which a plurality of pixel circuits including liquid crystal elements are configured in a matrix; an LCD driver for applying a predetermined data signal to the pixel circuits of the display panel; and a selecting driver for applying a predetermined scanning signal to the display panel to select a predetermined pixel circuit. FIG. 20 illustrates an equivalent circuit diagram of the pixel circuit included in the LCD device. As illustrated, this pixel circuit includes a data signal line 101 for applying a data signal from the LCD driver; a scanning signal line 100 for applying a scanning signal from the selecting driver; a field effect transistor 102 functioning as a switching device in response to the scanning signal; a liquid crystal element 103 for adjusting quantity of display light through the pixel; and an auxiliary capacitance element 104 having predetermined capacitance. The field effect transistor 102 is connected to the scanning signal line 100 at its gate, and to the data signal line at its drain. Also, one end of the liquid crystal element 103 and the auxiliary capacitance element 104 is each connected to a source of the field effect transistor 102, and another end of these elements is each connected to a common electrode Vcom which is a common electrode for all the pixel circuits. In this pixel circuit, when the scanning signal is provided, i.e., the scanning signal line 100 is selected, the field effect transistor 102 turns on, thereby causing a voltage (of the data signal) applied to the data signal line to be applied to the auxiliary capacitance element 104. Then, once the period during which the scanning signal line 100 is selected ends, the field effect transistor 102 turns off, while a voltage across the capacitance at the beginning of this off state is maintained by electric charge stored (or held) in the auxiliary capacitance element 104. Here, since light transmissivity or light reflectivity of the liquid crystal element 103 varies depending on the applied voltage, application of a voltage corresponding to image data to the data signal line 101 enables display luminance (or display tone) of the pixel to be varied according to the image data when the scanning signal line 100 is selected.
Here, a driver for driving a digital LCD device selects one of a plurality of predetermined reference voltages based on digital data given externally, and applies the selected reference voltage to a pixel element in a specific pixel circuit. As the number of gray levels increases, this digital LCD driver requires an increased number of elements included therein, and thus, ends up in higher manufacturing cost. To deal with this problem, frame rate control techniques (hereinafter referred to as the "FRC techniques") have been developed as a control technique for increasing gray levels without increasing the number of devices used therein, while still using a digital LCD driver.
The FRC techniques achieve pseudo-halftone luminance for human eyes by applying two different driving voltages to a predetermined pixel element in multiple frames. FIGS. 21A-21C illustrate an example for multi-gray-level display (e.g., three-gray-level display) by an FRC technique. Here, two different driving voltages (i.e., "high" voltage and "low" voltage) are applied to a predetermined pixel element in adjoining frames 1 and 2, thereby allowing three-gray-level (i.e., multi-gray-level) display. In this case, the frame frequency is 60 Hz. An AC (alternate current) drive is performed by a frame inverting technique where the polarity of the applied voltage is inverted for each frame.
FIG. 21A illustrates a driving voltage in each frame for displaying a pixel A with lowest luminance, FIG. 21B illustrates a driving voltage in each frame for displaying a pixel B with highest luminance, and FIG. 21C illustrates a driving voltage in each frame for displaying a pixel C with a middle luminance. As shown in FIG. 21A, a low voltage with respect to the voltage potential VCOM of the common electrode applied in both frames 1 and 2 creates a pixel A with the lowest luminance. By contrast, as shown in FIG. 21B, a high voltage applied in both frames 1 and 2 creates a pixel B with the highest luminance. Then, as shown in FIG. 21C, a positive low voltage applied in frame 1, and a negative high voltage applied in frame 2 generate a pixel C with a middle luminance between the luminance of the pixel A shown in FIG. 21A and the luminance of the pixel B shown in FIG. 21B.
When the middle luminance shown in FIG. 21C is obtained by the FRC technique, a low-luminance pixel is displayed in frame 1, and a high-luminance pixel is displayed in frame 2. As a result, pixels with different luminances are displayed in adjoining frames. Thus, luminance variations of the displayed pixel C contains a flicker component which has a half of the frame frequency, i.e., 30 Hz. Here, in general, it is observed that flicker components whose frequency is lower than 50 Hz are noticeable for human eyes. Thus, if all pixels in a display screen are driven at the same phase as the middle-luminance pixel C shown in FIG. 21C, flicker components are conspicuous in the entire display screen. As a result, display quality of the display device would be deteriorated.
To address this issue, i.e., in order to achieve flickerless middle luminance of FIG. 21C, there have been techniques for spatially eliminating the associated flicker components by applying the driving voltage shown in FIG. 21C to some pixels, and by applying voltages different from that of FIG. 21C to other pixels, thereby allowing pixels displayed by these pixel circuits to be evenly positioned within a display screen in a diffused manner.
For example, in order to apply voltages different from that of FIG. 21C, the following three patterns may be used. In a first pattern, a positive high voltage is applied in frame 1, and a negative low voltage is applied in frame 2. In a second pattern, a negative high voltage is applied in frame 1, and a positive low voltage is applied in frame 2. In the third pattern, a negative low voltage is applied in frame 1, and a positive high voltage is applied in frame 2. FIGS. 22A-22C illustrate the above patterns in which these voltages are applied. FIG. 22A shows a driving voltage for the first pattern, and a pixel D generated by applying the driving voltage for the first pattern. FIG. 22B shows a driving voltage for the second pattern, and a pixel E generated by applying the driving voltage for the second pattern. FIG. 22C shows a driving voltage for the third pattern, and a pixel F generated by applying the driving voltage for the third pattern. These pixels D, E and F; and the pixel C shown in FIG. 21C are positioned to be diffused spatially, i.e., their positions in the display screen are evenly allocated. FIG. 23 illustrates an exemplary allocation of the pixels C, D, E, and F. FIG. 23 illustrates pixels in four rows for each of columns 1-4 where symbols C, D, E, and F in the figure correspond to the above-identified pixels C, D, E, and F, respectively. Positioning each pixel in this manner allows pixels generated by application of the same driving voltage to be diffused in the display screen in a specific frame, thereby spatially eliminating the above-mentioned flicker components.
According to the conventional FRC techniques described above assume that luminances of pixels generated by applying the same combination of driving voltages, e.g., luminances of pixels C, D, E, and F are identical with each other. However, there exists parasitic capacitance in the equivalent circuit including the field effect transistor 102 shown in FIG. 20. As a result, when two cases in which positive and negative voltages having the same driving voltage (high voltage or low voltage) are applied are compared with each other, the voltage potentials VDL, VDH, and VDM1-VDM4 shown in FIGS. 21A-21C and 22A-22C can be shifted from ideal levels. Thus, pixels generated by applying the same combination of driving voltages may have different luminances. For example, the middle luminance of pixels C and E, and the middle luminance of pixels D and F may be different from each other although these middle luminances should be the same.
The above-mentioned luminance differences may be noticeable for human eyes especially when flicker components are to be eliminated spatially. That is, the pixels C and E in the columns 1 and 3 are generated by being driven only by high voltages with positive polarity and negative polarity as shown in FIGS. 21C and 22B. The pixels D and F in the columns 2 and 4 are generated by being driven only by high voltage with positive polarity and low voltage with negative polarity as shown in FIGS. 22A and 22C. As a result, the luminances are the same on every other column while adjoining columns have different luminances with each other. Thus, stripe-shaped variations in luminance extending along the column direction is conspicuous for human eyes. Even if the pixels C and F shown in FIG. 23 are interchanged, this problem still remains, and in such a case, stripe-shaped variations in luminance extending along the row direction would be conspicuous.

Method and apparatus for displaying halftone in a liquid crystal display


A technique verifies the presence of a user to applications stored on a distributed network system using a single password. The technique generally comprises computing a one-way hash value of the password that is initially provided by the user to a workstation during a login procedure. This initial hash value is stored by the workstation so that it may be readily accessible for authenticating the user to other applications of the system. These other applications query the user as to its identity by issuing an operating system application programming interface (API) call that specifies, e.g., "quiz user for password". The API call invokes a routine that requests the user's password and, in response to that password, hashes it and compares the resulting hash value with the stored hash value. If the values match, the user is reliably authenticated.

A distributed network system typically includes various computer nodes interconnected by a communications medium. The computer nodes may include nodes that are directly accessed by users, e.g., workstations, and nodes running specialized applications, e.g., servers. These nodes, the applications running on these nodes, and the users of the distributed system may be referred to as "principals." The methodology employed to reliably verify the identity of a user of a distributed network system prior to allowing the user access to system resources and applications is referred to as authentication. Authentication is generally performed on behalf of the principals.
In a typical distributed network system, the user sends a password to each application running on a remote node in order to access its resources. If the password for each application is different, remembering the password and its associated application may be rather difficult and unpleasant. The user could simply set each password for each application to the same value, but this presents the problem that if the user changes one password and forgets to change the others, the passwords will diverge.
On the other hand if the user has the same password for all applications, the local application with which the user "logs-in" typically saves the entered password and automatically sends it to remote applications as needed. This type of remote authentication is susceptible to a password-based system threat known as eavesdropping, i.e., interception of the password by wiretapping the network. To counter such a threat, cryptography is often used to preserve the confidentiality of the transmitted password when authenticating the user to remote applications.
A well-known cryptographic technique used to perform remote authentication is public key cryptography. In this method of secure communication, each principal has a public encryption key and a private encryption key, and two principals can communicate knowing only each other's public keys and, of course, their own private keys. An encryption key is a code or number which, when taken together with an encryption algorithm, defines a unique transformation used to encrypt or decrypt data. A public key system may be used in such a way as to ensure that information being transmitted cannot be understood by an eavesdropper, as well as to ensure the authenticity of the sender of the information.
The manner in which a public key cryptography system operates to ensure authentication may be understood without reference to the mathematical transformations that are used for encryption and decryption. Public key cryptography is also referred to as "asymmetric" encryption because information encoded with a public key may be decoded only by using a complementary private key, the associated public and private keys defining a key pair. According to this type of encryption, the private key is known only to the owner of the key, while the public key is known to other principals in the system.
Accordingly, to effect a secure transmission of information to a recipient, a principal encodes ("encrypts") the information with the recipient's public key. Since only the intended recipient has the complementary private key, only that principal can decode ("decrypt") it. On the other hand, to prove to a recipient of information that the sender is who he purports to be, the sender encodes ("signs") the information with its private key. If the recipient can decode ("verify") the information, it knows that the sender has correctly identified itself. In public key cryptography, each principal is responsible for knowing its own private key and all the public keys are generally accessible from one location, typically a directory service (DS).
Operation of a public key cryptography system will now be described with reference to an illustrative login authentication exchange between a workstation, acting on behalf of a user, and a remote server. Basically, the workstation encrypts a message for confidentiality by performing a transformation using the server's public key, and a server decrypts the message by performing a transformation using its private key.
A user logs into the workstation with the user's password and the workstation derives a secret encryption key by applying a known hash algorithm to the password prior to deleting it. The workstation then requests the user's private key from a DS of the remote server. The user's private key has previously been encrypted under the same secret encryption key and stored as a credential of the directory. A credential is a table entry comprising the user's name and the user's private key; in other words the credential is a representation of the user in the computer. The remote server returns the encrypted private key to the workstation, which uses the secret key to decrypt and obtain the private key.
By demonstrating possession of the private key, the workstation may thereafter attempt to access distributed system-based services or applications on behalf of the user. For example, the user may attempt to log into a different workstation or server, attempt to access a different operating system or attempt to access applications such as Lotus Notes or Novell GroupWise. Each of these entities typically includes a component referred to as an authentication agent that maintains the user's identity and secret (e.g., password). Although the user has been generally authenticated on the network, these agents may not be aware of that authentication, and thus query the user for a password. This can consume considerable bandwidth and can be quite intrusive to the user, particularly in systems requiring users to be authenticated whenever a resource is accessed.
A known mechanism for solving this problem is a single sign-on mechanism. Here, a main application stores the secrets of the other applications and, in response to an inquiry from an application, provides the appropriate secret on behalf of the user. The user thus does not have to retype the secrets, as it is assumed that if the user has successfully logged into the main application, the workstation can access the secrets of the other applications and provide them to the applications on behalf of the user.
Specifically, a group of encrypted application secrets are associated with the user; this group of secrets is referred to as a "keychain". The keychain is assigned a public/private key pair, wherein all of the secrets of the keychain are encrypted with the public key and the private key for the keychain is encrypted with the user's password. When the user logs into the main application with its password, this password is used to decrypt the user's private keychain key. The workstation then forgets the password but keeps the private keychain key accessible. The encrypted application-specific secrets are decryptable with the private keychain key. An application-specific secret may therafter be retrieved from the keychain and decrypted with the private keychain key.
Notably for security reasons, the password used for logging into the main application is not retained at the workstation, primarily because malicious software could capture the password and use it to impersonate the user. When implemented in a straightforward way, however, the single sign-on mechanism precludes periodic quizzing of the user for a password. But there are instances, such as after a period of no activity from the user, when it may be useful to quiz the user for its password to ensure that it is indeed still the user.
One approach to inquirying as to the user's identity involves repeating the illustrative login exchange whenever the user is required to type a password. This is undesirable because the exchange typically involves communication with another computer (e.g., the DS server) and that server might be unavailable when attempting to verify the user's password. Another option is to assign an application the responsibility of quizzing the user for a password and further assign the application its own version of the password. This approach is also undesirable because if the user changes its main password, the two passwords will be different.
The present invention avoids the disadvantages associated with these prior approaches and is directed to a technique for dynamically authenticating a user to various services and applications in a distributed network system.

User presence verification with single password across applications


The methods for channel assignment and channel reassignment are suitable for SDMA systems that accommodate the dynamically adaptive spatial channel conditions and allow for more frequent reuse of conventional channels. Three methods for uplink channel assignment are described: a cost function method, a predictive method, and a hierarchical method. The cost function method computes a cost function for each conventional channel based on a weighted correlation matrix of spatial signatures (vectors) of active subscribers. A spatial channel is created for the selected conventional channel if it is in use. The predictive channel assignment method predicts the uplink received power and interference-plus-noise for each conventional channel. Either the conventional channel with the minimum interference-plus-noise level or the channel with the maximal SINR is selected and a spatial channel is also assigned if the selected channel is in use. The hierarchical method combines the cost function method and the cost function method. The downlink channel assignment method, when not constrained by the uplink channel assignment, assigns a conventional channel to a new connection by estimating the downlink interference-plus-noise level from a subscriber report, spatial signature and weight vector, and computing a predicted downlink received signal level. Three methods for call admission control include: a cost function method, a predictive method, and a load based channel assignment method.

Wireless communication systems are generally allocated a portion of the radio frequency (RF) spectrum for their operation. The allocated portion of the spectrum is divided into communication channels and channels are distinguished by frequency, time or code assignments, or by some combination of these assignments. Each of these communication channels will be referred to as conventional channels, and a conventional channel will correspond to a fill-duplex channel unless otherwise noted. The establishment of a communication link in a communication system depends not only on the availability of a conventional channel but also on the quality of communication that will result from the use of a given available conventional channel.
In wireless communication systems, a conventional channel is used for communication between a base station and a subscriber station. A base station provides coverage to a geographic area known as a cell and may be a point-of presence providing connection between the subscriber station and a wide area network such as a Public Switched Telephone Network (PSTN). The underlying motivation for the use of cells in wireless systems is the reuse of the RF spectrum in geographically different areas. The reuse of the frequency spectrum can introduce co-channel (intercell) interference between users in different cells that share a common conventional channel. If co-channel interference is not carefully controlled, it can severely degrade the quality of communications. System capacity is in general limited by interference because of the reduction in the number of reusable channels of acceptable quality.
Another source of conventional channel quality degradation is adjacent channel (intracell) interference caused by other conventional channels within a given cell. Ideally, within a given cell each conventional channel should be completely isolated from all of the other conventional channels (orthogonal). In practical systems, full orthogonality between channels can not be ensured because of the complexity and cost such a requirement would place on the system design. For example, adjacent channel interference can result, in FDMA systems, from RF carrier frequency offsets and imperfect filters; in TDMA systems, from timing offset and jitter; and, in CDMA systems, from synchronization inaccuracies or RF multipath propagation.
The more recently introduced SDMA systems (Roy et al., U.S. Pat. No. 5,515,378) allow multiple subscribers within a given cell to simultaneously share the same conventional channel without interfering with one another, and further, allow more frequent reuse of conventional channels within a geographical area covering many cells. SDMA exploits the spatial distribution of subscribers in order to increase usable system capacity. Because subscribers tend to be distributed over a cell area, each subscriber-base station pair will tend to have a unique spatial signature characterizing how the base station antenna array receives signals from the subscriber station, and a second spatial signature characterizing how the base station antenna array transmits signals to the subscriber station. Subscribers sharing the same conventional channel are said to be using different spatial channels. As in the case of FDMA, TDMA, and CDMA systems, spatial channels in a SDMA system may not be perfectly orthogonal because of hardware limitations and multipath propagation. It should be noted that non-spatial multiplexing (e.g., FDMA, TDMA, and CDMA), when used in combination with antenna array patterns that are controlled by using spatial processing, is referred to as SDMA in the context of this invention. In practice, spatial signatures and antenna arrays can be used in a non-spatial-division-multiple-access system configuration for enhancing communications between base stations and subscribers by use of spatial signal processing techniques. In these cases, the label SDMA will still be used in the context of the description that follows.
FIG. 1 shows an example of a wireless SDMA TD/FD/CDMA system (Barratt et al., U.S. patent application Ser. No. 08/375,848) in which a number of subscriber stations (symbolically shown as handsets) 20, 22, 24 are being served by base station 100 that may be connected to a wide area network (WAN) 56 for providing any required data services and connections external to the immediate wireless system. Switching network 58 interfaces with WAN 56 for providing multichannel duplex operation with the WAN by switching incoming WAN data to lines 60 of base station 100 and switching outgoing signals from base station 100, on line 54 to the WAN. Incoming lines 60 are applied to signal modulators 62 that produce modulated signals 64 for each subscriber station the base station is transmitting to. A set of spatial multiplexing weights 74 for each subscriber station are applied to the respective modulated signals in spatial multiplexers 66 to produce spatially multiplexed signals 68 to be transmitted by a bank of multichannel transmitters 70 using transmit antenna array 18. The SDMA processor (SDMAP) 48 produces and maintains spatial signatures for each subscriber station for each conventional channel, calculates spatial multiplexing and demultiplexing weights for use by spatial multiplexers 66 and spatial demultiplexers 46, and uses the received signal measurements 44 to select a channel for a new connection. In this manner the signals from the current active subscriber stations, some of which may be active on the same conventional channel, are separated and interference and noise suppressed. When communicating from the base station to the subscriber stations, an optimized multilobe antenna radiation pattern tailored to the current active subscriber station connections and interference situation is created. An example of a transmit antenna pattern that may be created is shown in FIG. 2.
Returning to FIG. 1, spatial demultiplexers 46 combine received signal measurements 44 from the multichannel receivers 42 and associated antenna array 19 according to spatial demultiplexing weights 76, a separate set of demultiplexing weights being applied for each subscriber station communicating with the base station. The outputs of spatial demultiplexers 46 are spatially separated signals 50 for each subscriber station communicating with the base station, which are applied to signal demodulators 52 to produced demodulated received signals 54 for each subscriber station communicating with the base station. In an alternate embodiment, the demultiplexing and demodulation processing are performed together in a nonlinear multidimensional signal processing unit.
The demodulated received signals 54 are then available to switching network 58 and WAN 56.
In an FDMA system implementation, each multichannel receiver and each multichannel transmitter is capable of handling multiple frequency channels. In other embodiments, multichannel receivers 42 and multichannel transmitters 70 may instead handle multiple time slots, as in a TDMA system; multiple codes, as in a CDMA system, or some combination of these well known multiple access techniques (Barratt et al., U.S. patent application Ser. No. 08/375,848).
In practical systems that may involve hundreds or thousands of subscriber stations, perfect separation or orthogonality between every subscriber station, following the application of SDMA processing, cannot be insured because of the complexity and cost that such a requirement would place on the system design. If the separation of subscriber station connections post-SDMA processing cannot be ensured, the extended capacity of the SDMA will be limited and interference between subscribers will occur from the use of SDMA techniques. The consequence of this practical limitation is that a method for minimizing the interference and thereby maximizing the effective channel capacity of the SDMA system is required.
Even if two or more subscriber stations are not perfectly separated or orthogonal after SDMA processing, it still may be possible to share a common conventional channel in a TDMA, FDMA or CDMA system using SDMA technology. From a practical point of view, it is not required that the subscriber stations be perfectly separated after SDMA processing to share a common conventional channel. It is only required that the interference between subscribers sharing a common conventional channel post-SDMA processing be low enough so as not to reduce the quality of communications below a prescribed level.
Because of the interference introduced by frequency reuse and the fragile nature of orthogonality for conventional and spatial channels, all wireless multiple access communications systems need a method for base station and channel assignment that minimizes these adverse effects when a new call or connection between a base station and a subscriber is made. The labels new subscriber and new connection will be used interchangeably to denote a new call or connection between a base station and a subscriber station, and the labels active subscriber, existing connection and existing subscriber will be used interchangeably to denote a call or connection in-progress between a base station and a subscriber station. If not careful, the new subscriber may be assigned to a base station and a channel on which poor quality is experienced due to excessive interference. Moreover, the addition of a new subscriber has the potential consequence of adversely affecting the quality of communications on existing connections. Also, existing subscribers can suffer from increased channel interference from the addition of a new subscriber, or other unrelated causes, that can require moving subscribers from currently assigned channels to new channels in order to restore Acceptable quality communications. Channel re-assignment methods, using decision processes similar to those used for initial base station and channel assignment, are also required.
Prior art channel assignment and reassignment methods are based on measurements of physical phenomena such as the received signal strength indication (RSSI) or the co-channel interference on different conventional channels. Barnett, in U.S. Pat. No. 5,557,657, describes a method for handover between an overlay cell and an underlay cell depending on the RSSI. Booth (U.S. Pat. No. 5,555,445) describes a method for intercell handoff in which an intracell handoff from one conventional channel to another is first attempted, and the success or failure of the handoff is indicated by the RSSI. Knudsen (U.S. Pat. No. 5,448,621) describes a method for reallocating conventional channels between cells that depends on the number of unused conventional channels in each cell (i.e., the cell load). Grube et al. (U.S. Pat. No. 5,319,796) outlines a method for measuring co-channel interference on a conventional channel by placing additional receivers in the coverage area of the co-channel user and then transmitting feedback information on measured co-channel interference to a channel assignment controller. In all of these methods, the processes of channel assignment and reassignment do not take the spatial distribution of the subscribers into account, nor do they consider how the RSSI and co-channel interference jointly affect the signal quality of the new connection.
Hanabe (U.S. Pat. No. 5,475,864) describes a channel assignment method for sectorized cells which have static antenna beam patterns. Hanabe does not consider what happens with fully adaptive SDMA systems in which beam patterns dynamically change depending on which subscribers are active at any given time. Furthermore, the channel assignment of spatial channels made possible by SDMA is never addressed.
If two subscribers with similar spatial signatures were to be assigned to the same conventional channel, either at the same base station or at two different base stations, serious interference would render the channel unusable to both subscribers. Hence, there is a need for a new method of channel assignment for advanced, fully adaptive SDMA systems that can predict, a priori, the quality of a spatial or conventional channel; i.e., before the new connection is assigned to a given base station and channel. Also, there is a need for a SDMA channel assignment method that can predict the impact of a new connection on existing connections and can perform call admission control as necessary. The availability of such base station and channel assignment, reassignment, and admission control methods would allow SDMA methods to increase system capacity by better isolating subscribers while maintaining acceptable communications quality.

Channel assignment and call admission control for spatial division multiple access communication systems


A gate driving circuit includes plural-stage output circuits, an Nth stage output circuit of the plural-stage output circuits includes an Nth stage shift register and a mixer. The Nth stage shift register is configured to output an Nth pulse signal. The mixer is coupled to the Nth stage shift register and an (N+M)th stage shift register, for respectively outputting a first clock signal and a predetermined pulse signal during different periods according to the Nth pulse signal and an (N+M)th pulse signal of the (N+M)th stage shift register. Wherein pulse widths or phases of the first clock signal and the predetermined pulse signal are different, and N and M are positive integers.

1. Field of the Invention
The present invention relates to a gate driving circuit, and more particularly, to a gate driving circuit capable of outputting a gate signal with two different pulses.
2. Description of the Prior Art
An organic light emitting diode display device is a display device utilizing organic light emitting diode pixels to emit light for displaying images. Brightness of an organic light emitting diode is proportional to amount of current flowing through the organic light emitting diode. Generally, in order to control the amount of the current flowing through the organic light emitting diode, the organic light emitting diode pixel comprises a current control switch for controlling the amount of the current flowing through the organic light emitting diode according to a display voltage at a gate terminal of the current control switch, so as to further control the brightness of the organic light emitting diode.
However, a threshold voltage of the current control switch of each organic light emitting diode pixel may be different. The difference of the threshold voltage of the current control switch may affect the brightness of the organic light emitting diode. In order to compensate the difference of the threshold voltage of the organic light emitting diode pixel, a compensation circuit is arranged within each organic light emitting diode pixel to operate with pulse signals having different pulse widths or phases. The gate driving circuit of the prior art can only output one kind of pulse signal, and is not able to output a gate signal with two different pulses according to design of the compensation circuit. Therefore, an additional signal generation circuit must be arranged in the organic light emitting diode display device of the prior art for providing other kind of pulse signal, such that the organic light emitting diode display device of the prior art has a more complex hardware structure.

Gate driving circuit and display device having the same


A latch assembly for use with a panic exit device, particularly a top latch having a U-shape which engages a stem portion of a T-shaped receiving lug mounted overhead to a top member of the door frame. The U-shaped top latch is pivotably mounted to the active stile of the door. The latch assembly causes the U-shaped latch to pivot upward to capture the stationary T-shaped receiving lug, or pivot downwardly to disengage from the T-shaped receiving lug. The latch member is in sliding and abutting engagement with two latch plates which slide in one direction to retain the latch member in a downward orientation to hold the latch in an open position, and slide in an opposite direction to allow the latch member to pivot upwardly upon engaging pressure by the strike. A wedge is caused to slide into blocking engagement with the latch when it is in the closed position. The wedge is removed from the blocking position by movement of a panic bar of a panic exit device mounted onto the door, and the wedge, once moved to disengage from the latch member, allows the latch to pivot to the open position.

This invention relates to panic exit devices having one or more latches carried by the door which engage receiving portions mounted on door frameworks surrounding the door. In particular, the invention relates to panic exit devices having one or more vertically operating latches at the top and/or bottom of the door. Examples of such devices wherein the bolts may be retracted by a panic exit device are described in U.S. Pat. No. 3,993,335 to Schmidt, U.S. Pat. No. 3,940,886 to Ellingson, Jr., U.S. Pat. No. 4,839,988 to Betts et al and U.S. Pat. No. 5,114,192 to Toledo et al.
There are numerous types and styles of mechanisms used for operating the popular commercial and industrial door latches wherein the latches such as bolts extend vertically from the top and bottom of the door and engage the top and bottom door frame members. These devices can include a panic bar release mechanism on one side of the door for rapid release of the bolts by depressing the panic bar to open the door.
Another desirable feature of a latch system is a provision wherein after the latch is disengaged by actuating the panic exit device, the latch is retained in a condition for easy re-engagement when the door closes. In an extending bolt-type latch a mechanism for retaining the retracted bolt in a retracted position after the door is opened and continuously while the door is opened, can serve this function. This feature prevents the need to continue pressure on the panic bar or the key in order to prevent the bolt from interfering with objects such as the ground or the door frame while the door is being opened and returned to the closed position. Thus, the bolt retaining mechanism is designed to hold the bolt in a retained condition and to trigger and release the bolt when the door again reaches the closed position. U.S. Pat. Nos. 5,114,192, 4,283,882, 3,993,335 and 3,334,500 show such bolt or latch mechanisms.


A non-transitory computer-readable medium having computer-readable instructions stored thereon which, when executed by a computer, cause the computer to perform a method of processing data comprising the steps of: receiving data associated with event instances; and for each of a plurality of iteration methods: partitioning the incoming event instances into logical data partitions; assigning an identifier to each event instance such that events classified in the same logical data partition receive the same identifier and a given event instance is always assigned the same identifier; and inserting each event instance into a doubly-linked list associated with the identifier in an appropriate location.

There are many database programs in the world. There are relational databases, which are great at cross-referencing tables. There are various types of databases that search based on tags or keywords or Regular Expressions (regexps). There even are some programs that call themselves time-series databases. These generally require that the data be regular (evenly spaced in time) or artificially treat it as such. A few time-series products can handle irregular data (data occurring at random time intervals) but focus on its analysis rather than efficient storage and iteration over it. What does not exist is a specialized database that provides maximally efficient storage, retrieval, and scanning of stream data.
As a simple example, consider stock trades and quotes ("tick" data). Tick data from a live feed arrives irregularly. Once the data arrives, a database application must parse, clean and convert ("normalize") the data into a usable form. For many applications, it may be possible to predict the ways the stored tick data will need to be accessed and thus, the application may be optimized to access the data. For example, some applications may wish to iterate over all ticks in a given stock or just all trades in a given stock.
Certainly, queries by stock or by trades in a given stock can be performed in any of the aforementioned databases. However, such a query may be inordinately slow because of the way the data is stored and accessed. What is absent in the current art, is a database specialized for iteration over stream data in a set of pre-specified user-defined ways. With the emergence of high frequency trading, a database that can handle vast amounts of irregular stream data and efficiently iterate over that data may provide significant advantages. This is also true in myriad other areas where a variety of event types arrive in the form of irregular stream data, and either volumes are large or latencies are required to be low. Examples include intelligence, biotechnology, customer transaction management, system or security event logging, and email or message management.

Databases and methods of storing, retrieving, and processing data