A memory system includes a non-volatile memory, a data buffer in which data read out from the nonvolatile memory are stored prior to transmission to an initiator that is requesting the data, a port through which the initiator sends a request for the data and through which the data in the data buffer are transmitted to the initiator. When the port is connected to a first initiator at a time both first data requested by the first initiator and second data requested by a second initiator are stored in the data buffer and the second data become ready for transmission prior to the first data, the second data are transmitted through the port prior to the first data.

A memory system of one type includes non-volatile memories and communicates with a computer through a SAS (Serial Attached SCSI) interface. Hereinafter, the computer which can communicate with the memory system is called an initiator. When the SAS interface is used, a communication path between the memory system and the initiator is established by an OPEN sequence. In this case, if the memory system receives a read command which instructs readout of data, the memory system buffers the data in a data buffer, and transmits the data buffered in the data buffer to the initiator.
However, if a connection with the initiator is not established in spite of performing the OPEN sequence, the conventional memory system repeatedly performs the OPEN sequence. For that reason, data transmission efficiency of the conventional memory system may be poor.

Memory system that selects data to be transmitted from a data buffer through a port


A low-dropout regulator with a single-transistor-control providing improved transient response and stability is disclosed. The single-transistor-control provides a dynamic resistance at the output of the regulator for minimizing undershoot and overshoot, and hence improves transient response. Since the single-control transistor reduces the output resistance of the regulator, the output pole is pushed to a sufficiently high frequency without affecting stability. Therefore, the limited choice of combinations of the output capacitance and its equivalent-series-resistance is substantially relaxed.

A low-dropout (LDO) regulator accepts an unregulated input voltage (VIN) and provides a regulated output voltage (VOUT) that is nearly independent of output current (e.g. a load current). A PMOS pass transistor is used to minimize the voltage difference between the input and output of a LDO regulator, and hence increases power conversion efficiency.
FIG. 1 shows the schematic of a typical LDO regulator according to the art, which consists of a pass transistor, an error amplifier, a reference voltage, a feedback resistor network and an optional output capacitor. Frequency compensation to achieve stability in a typical LDO is necessary as there are two high-impedance nodes, which are at the error amplifier output and at the drain of pass transistor. To provide such frequency compensation dominant-pole compensation and pole-zero cancellation are commonly used in the art, but these limit the choices of combinations of the output capacitance (COUT) and its equivalent-series-resistance (RESR) for LDO regulator stability. Furthermore, since the loop bandwidth of a conventional LDO is degraded by dominant-pole compensation, optimization between stability and transient response is difficult to achieve.


A dual fuel heating system can be used in a gas appliance. The system can have an air shutter to regulate an amount of air that can mix with the fuel for combustion. The air shutter can be configured to have different positions depending on the type of fuel to be used.

1. Field of the Invention
Certain embodiments disclosed herein relate generally to a heating source for use in a gas appliance particularly adapted for dual fuel use. The gas appliance can include, but is not limited to: heaters, boilers, dryers, washing machines, ovens, fireplaces, stoves, etc.
2. Description of the Related Art
Many varieties of heating sources, such as heaters, boilers, dryers, washing machines, ovens, fireplaces, stoves, and other heat-producing devices utilize pressurized, combustible fuels. Some such devices operate with liquid propane, while others operate with natural gas. However, such devices and certain components thereof have various limitations and disadvantages.

Dual fuel heating system and air shutter


A separator includes a porous substrate having a plurality of pores; a porous coating layer formed on at least one surface of the porous substrate and made of a mixture of a plurality of inorganic particles and a binder polymer; and a dot pattern layer formed on a surface of the porous coating layer and having a plurality of dots made of polymer and arranged at predetermined intervals. The separator may control short-circuit between positive and negative electrodes though an electrochemical device is overheated. Also, a united force to an electrode is enhanced due to the polymer dot pattern layer, thereby preventing the electrode and the separator from being separated. Accordingly, inorganic particles of the porous coating layer formed on the porous substrate are not separated, thereby improving stability of an electrochemical device.

Recently, there has been an increasing interest in energy storage technology. Batteries have been widely used as energy sources in the fields of cellular phones, camcorders, notebook computers, PCs and electric cars, resulting in intensive research and development into them. In this regard, electrochemical devices are one of the subjects of great interest. Particularly, development of rechargeable secondary batteries has been the focus of attention.
Among currently used secondary batteries, lithium secondary batteries developed in early 1990's have a higher drive voltage and a much higher energy density than those of conventional batteries using a liquid electrolyte solution such as Ni-MH batteries, Ni—Cd batteries, and sulphuric acid-lead batteries. For these reasons, the lithium secondary batteries are greatly spotlighted. Such a lithium secondary battery is assembled while interposing a separator between positive and negative electrodes. The separator is an important component that plays a role of ion passage in the battery and prevents the positive and negative electrodes from being directly contacted and thus short-circuiting the battery.
In the safety characteristics of the electrochemical device, overheating of the electrochemical device may cause thermal runaway, and explosion may occur when a separator is pierced. In particular, a polyolefin porous substrate commonly used as a separator of an electrochemical device shows extreme thermal shrinking behavior at a temperature of 100° C. or above due to the features of its material and its manufacturing process such as elongation, so there may occur an electric short circuit between positive and negative electrodes.
In order to solve the above safety-related problems of the electrochemical device, Korean Laid-open Patent Publication No. 10-2006-72065 and No. 10-2007-231 disclose a separator 10 having a porous coating layer formed by coating at least one surface of a porous substrate 1 having many pores with a mixture of inorganic particles 3 and a binder polymer 5 (see FIG. 1). In the separator 10, the inorganic particles 3 in the porous coating layer formed on the porous substrate 1 act as a kind of spacer that may keep a physical shape of the porous coating layer, so the inorganic particles 3 restrain thermal shrinkage of the porous substrate when the electrochemical device is overheated. In addition, interstitial volumes exist among the inorganic particles, thereby forming fine pores.
As mentioned above, the porous coating layer formed on the porous substrate contributes to the improvement of safety of the separator. However, the porous coating layer containing inorganic particles may deteriorate a united force between the electrode and the separator. Thus, during an assembling process of an electrochemical device such as a taking-up and assembling process of an electrode and a separator, the electrode and the separator may be more likely not closely adhered to each other but separated from each other, so lithium ions may be not effectively transferred, which may deteriorate the performance of a battery. In addition, the inorganic particles of the porous coating layer may be separated while the electrode and the separator are separated, and the separated inorganic particles may act as a local defect of the electrochemical device, thereby giving a bad influence on the safety of the electrochemical device.

Separator for providing a uniting force to electrode and electrochemical cell containing the same


Disclosed are methods for the preparation of monofucosylated and sialylated derivatives of the compound .beta.Gal(1-4).beta.GlcNAc(1-3).beta.Gal(1-4).beta.GlcNAc-OR. In particular, the methods of this invention provide for a multi-step synthesis wherein selective monofucosylation is accomplished on the 3-hydroxy group on only one of the GlcNAc units found in the .beta.Gal(1-4) .beta.GlcNAc (1-3) .beta.Gal (1-4) .beta.GlcNAc-OR compound. In this step, monofucosylation is achieved by use of the .alpha.(1-3)fucosyltransferase.

1. Field of the Invention
This invention is directed to methods for the preparation of monofucosylated and sialylated derivatives of the compound .beta.Gal(1-4).beta.GlcNAc-(1-3).beta.Gal(1-4).beta.GlcNAc-OR. In particular, the methods of this invention provide for a multi-step synthesis wherein selective monofucosylation is accomplished on the 3-hydroxy group on only one of the GlcNAc units found in the .beta.Gal(1-4).beta.GlcNAc-(1-3).beta.Gal(1-4).beta.GlcNAc-OR compound. In these methods, monofucosylation is achieved by the use of an .alpha.(1-3)fucosyltransferase. This invention is also directed to compounds prepared by the herein described methods.
2. References
The following references are cited in this application as superscript numbers at the relevant portion of the application:
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All publications and patent applications mentioned in this specification are indicative of the level of skill of those skilled in the art to which this invention pertains. All publications and patent applications are herein incorporated by reference in their entirety to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference in its entirety.
3. State of the Art
The art teaches that specific oligosaccharides such as sialylated and fucosylated structures are involved as ligands in cell adhesion phenomena..sup.1a-1c Similarly, oligosaccharide glycosides relating to blood group determinant structures have been found to impart immunosuppressive and tolerogenic properties to mammals when the mammals were previously challenged with an antigen. See Ippolito et al..sup.22, which application is incorporated herein by reference in its entirety. In this regard, oligosaccharide glycosides relating to blood group determinant structures include the compound .beta.Gal(1-4).beta.GlcNAc(1-3).beta.Gal(1-4).beta.GlcNAc-OR depicted in FIG. 1 of this application as compound 1a.
Ippolito et al..sup.22 further discloses that blood group determinant oligosaccharide glycosides having a sialic acid group (or an analogue thereof) at the non-reducing sugar terminus of the oligosaccharide glycosides and which are also monofucosylated possess immunosuppressive and tolerogenic properties (e.g., sialyl Lewis.sup.X --Compound III in FIG. 12 of Ippolito et al..sup.22).
In view of the above, we desired to prepare a monofucosylated derivative of compound 1a having a sialic acid group (or an analogue thereof) at the non-reducing sugar terminus of this compound wherein the fucosyl group was pendant to the 3-hydroxy of only one of the GlcNAc groups.
A synthetic approach employing enzymatic sialylation and fucosylation steps is particularly appropriate in order to provide an efficient route for the preparation of sialylated and monofucosylated derivatives of compound 1a. In this regard, since the work of Sabesan et al.,.sup.2 -sialyltransferases, mostly the .beta.Gal(1-4).beta.GlcNAc .alpha.(2-6)- and the .beta.Gal(13/4).beta.GlcNAc .alpha.(2-3)-sialyltransferases from rat liver and the .beta.Gal(1-3).beta.GalNAc .alpha.(2-3)sialyltransferase from porcine submaxillary gland have often been used for synthetic purposes..sup.3 The former two sialyltransferases are useful in sialylating a terminal .beta.Gal(1-4).beta.GlcNAc- group in an oligosaccharide glycoside. The latter sialyltransferase which has a wide acceptor specificity, is useful in sialylating a terminal .beta.Gal(1-3).beta.GlcNAc-group in oligosaccharide glycosides based on the Lewis.sup.c (Type I) backbone.sup.4 but, because of the low affinity of this enzyme for the Type II backbone, the synthesis of sialylated N-acetyllactosaminyl structures, such as those present in the sialyl Lewis.sup.x,.sup.5 sialyl dimeric Lewis.sup.x6 or the corresponding internally monofucosylated derivative.sup. 7, by use of this sialyltransferase is much more difficult..sup.4
By using fucosyltransferases of various specificities, the biosynthetic pathway leading to sialyl Lewis.sup.x and the sialylated dimeric Lewis.sup.x structures has been shown to proceed by the sequential sialylation followed by fucosylation of the Type II precursors..sup.8a-d A similar process "extension, sialylation, fucosylation" has also been proposed.sup.9 to lead to internally fucosylated repetitive Type II terminal structures, such as: .alpha.Neu5Ac(2-3).beta.Gal(1-4).beta.GlcNAc(1-3).beta.Gal(1-4)-[ .alpha.Fuc(1-3)].beta.GlcNAc-..sup.9 The identification of the new terminal structure .beta.Gal(1-4).beta.GlcNAc(1-3).beta.Gal(1-4)-[[.alpha.Fuc(1-3)].beta.GlcN Ac-, defined by the antibody ACFH-18.sup.10, led to a proposed new biosynthetic pathway such as "elongation followed by selective internal fucosylation". While patterns of initial internal monofucosylation of di-N-acetyllactosaminyl glycolipids have been observed for fucosyltransferases present in LECII Chinese Hamster Ovary mutant.sup.11 and in human colonic adenocarcinoma Colo 205 cells.sup.8b, these fucosyltransferases are not readily available and/or do not selectively lead to monofucosylated structures. Similarly, while fucosyltransferases possessing the specificity required for the synthesis of the internally fucosylated structure .alpha.Neu5Ac(2-3).beta.Gal(1-4)GlcNAc-.beta.Gal(1-4)[.alpha.Fuc(1-3)]GlcN Ac have been identified.sup.34 and in one case a recombinant enzyme.sup.35 has been identified, their availability is also limited. Moreover, other .alpha.(1-3)fucosyltransferases do not transfer L-fucose onto N-acetylglucosamine moieties found in acceptors possessing a terminal .alpha.Neu5Ac(2-3).beta.Gal(1-4 ).beta.GlcNAc- sequence..sup.12,13,34 It has already been noted that "the order of addition of .alpha.(1-3) fucose in N-acetyllactosaminyl sequences of glycoconjugates will then depend upon the particular .alpha.(1-3)fucosyltransferase present".sup.11.
The single fucosylation at the internal N-acetylglucosamine unit of the .alpha.(2-6)sialyl di-N-acetyllactosaminyl sequence leading to the terminal structure .alpha.Neu5Ac(2-6).beta.Gal(1-4).beta.GlcNAc(1-3)-Gal(1-4)-[.alpha.Fuc(1-3 )].beta.GlcNAc-.sup.8a (also proposed for a sialylfucopentaose from human milk.sup.14) is in agreement with the proposed mutually exclusive glycosylation pattern of the .beta.Gal(1-4).beta.GlcNAc .alpha.(2-6)sialyltransferase and the .beta.Gal(13/4).beta.GlcNAc .alpha.(13/4)fucosyltransferase in the synthesis of asparaginyl linked oligosaccharides in glycoproteins..sup.15
In view of the above, processes which would enzymatically prepare sialylated and monofucosylated derivatives of compound 1a without the need to employ a fucosyltransferase specific for monofucosylation would be particularly desirable.
The present invention is based, in part, on the discovery of synthetic pathways which utilizes enzymatic fucosylation and sialylation steps and which result in the selective formation of monofucosylated derivatives of compound 1a without the need to employ a fucosyltransferase which is specific for monofucosylation on either of the GlcNAc units of compound 1a.

Methods for the synthesis of monofucosylated oligosaccharides terminating in di-N-acetyllactosaminyl structures


It is advantageous for a substance in the form of a liquid or a paste to be packaged under pressure and in the absence of any air inside a receptacle (1) which is hermetically closed by a valve (2) for the purpose of dispensing the substance. A convenient way of putting the substance under pressure therefore consists in using a resilient receptacle (1) which is prior deformed so that its walls (10) seek to return to their natural shape (in dashed lines) and exert a force on the substance. The present invention uses mechanical means for imparting said deformation. As a result, the receptacle (1) can be filled with substance at atmospheric pressure. The receptacle is constituted by a single envelope whose shape is of an appearance suitable for the market for this type of dispenser and is adapted to easy manipulation in the hand. Finally, if the dispenser is provided with a precompression pump type valve (2) up to 95% of the substance initially contained in the receptacle (1) can be dispensed.

One example of a distributor of this type is described in European patent application EP-0 248 755. Its receptacle includes a tube which is sufficiently flexible to expand very considerably when filled with a substance under pressure. As soon as a valve has been crimped in completely airtight manner on the tube, the pressure exerted on the substance by the tube is comparable to the filling pressure, with the resilient walls of the tube seeking to return to their original shape. As successive quantities of substance are dispensed, the internal pressure drops until the tube is no longer deformed. In order to implement this principle in practical manner, the flexible tube is additionally protected by a rigid external container which makes the dispenser easier to handle. A foam is advantageously disposed between the flexible tube and the rigid container in order to hold the various different envelopes of the receptacle in place within the dispenser.
The present invention retains the idea of prior deformation of a resilient receptacle for the purpose of putting the substance to be dispensed under pressure. However, it seeks to implement this principle in a manner which is simpler than that of the prior art. In particular, it is desirable for reasons of economy for the receptacle to be constituted by a single envelope.

Dispenser for a liquid or a paste put under pressure by prior deformation of a resilient receptacle


A read method of a memory device including a MLC includes the steps of performing a data read operation according to a first read command; determining whether error correction of the read data is possible; if, as a result of the determination, error correction is difficult, performing a data read operation according to a second read command; determining whether error correction of read data is possible according to the second read command; and if, as a result of the determination, error correction is difficult, performing a data read operation according to a Nth (N≧3, N is an integer) read command.

The present invention relates to flash memory devices and, more particularly, to a read method in which cell information can be read more accurately even when a cell threshold voltage has been shifted due to a cell retention characteristic.
A NAND flash memory device includes memory cells whose sources and drains are connected in series to one bit line to form a string. The memory cell generally has a transistor structure in which a floating gate and a control gate are stacked. A memory cell array is directly formed within a N-type well or P-type well formed in a P-type substrate or N-type substrate. The drain side of a NAND cell string is connected to the bit line through a select gate, and the source side is also connected to a source line through a select gate. The control gates of memory cells in adjacent cell stings are consecutively connected in a row direction and become a word line.
An operation of the NAND flash memory device is described below. A data write operation is sequentially performed starting from a memory cell, which is furthermost from the bit line. A control gate of a selected memory cell is applied with a high voltage Vpp, a control gate and a select gate of a memory cell on the bit line side of the selected memory cell are applied with an intermediate potential, and a bit line is applied with 0V or an intermediate potential depending on the data. If the bit line is applied with 0V, a potential is created between the drain and gate of the selected memory cell, so that electrons are injected into the floating gate. Due to this, the threshold voltage of the selected memory cell is increased.
In recent years, in order to further improve the degree of integration of flash memory, much research has been done on a multi-bit cell capable of storing a plurality of data bits in one memory cell. This kind of a memory cell is referred to as a "Multi Level Cell (MLC)". A memory cell of a single bit, corresponding to the MLC, is referred to as a "Single Level Cell (SLC)".
The MLC generally has four or more threshold voltage distributions, and four or more data storage states corresponding to the threshold voltage distributions. The MLC in which 2-bit data bits can be programmed has four data storage states; [11], [10], [00] and [01]. The states correspond to the threshold voltage distributions of the MLC.
For example, assuming that threshold voltage distributions of a memory cell are −2.7V or less, 0.3V to 0.7V, 1.3V to 1.7V, and 2.3V to 2.7V, the state [11] corresponds to −2.7V or less, the state [10] corresponds to 0.3V to 0.7V, the state [00] corresponds to 1.3V to 1.7V, and the state [01] corresponds to 2.3V to 2.7V. In other words, if the threshold voltage of the MLC corresponds to one of the four threshold voltage distributions, 2-bit data information corresponding to one of the states [11], [10], [00] and [01] is stored in the MLC.
As described above, the MLC has threshold voltage distributions corresponding to the square of 2 with respect to the number of bits that can be stored. That is, a MLC capable of storing m bits has 2m cell voltage distributions.
The cell voltage of the cell voltage distributions of the MLC is shifted as the storage period increases. This is called a "data retention characteristic". That is, while data is stored, and then read over a long period of time, the cell voltage is shifted, which may cause a read error.


A method of and an apparatus for determining tire shapes are provided which enable both an apparatus weight reduction and a determination accuracy improvement. The apparatus of the present invention includes: a portable base member; a non-contact displacement gage held on the base member so as to be freely movable along a predetermined scanning direction; a weight supported on the base member so as to be movable along the scanning direction; and means for symmetrically driving the displacement gage and weight while synchronizing them with each other. Using this apparatus, the method includes: setting the base member in proximity to a tire tread portion so that the displacement gage will scan the tread portion; allowing the displacement gage and weight to symmetrically move along the scanning direction while synchronizing them with each other; and determining the shape of the tread portion, based on an output from the displacement gage.

The present invention relates to a method of and an apparatus for determining tire shapes by using a non-contact displacement gage. More specifically, the present invention relates to a method of and an apparatus for determining tire shapes, which enable both a reduction in the weight of the apparatus and an improvement in determination accuracy.
Hitherto, the shapes and groove depths of the tread portion of a pneumatic tire have been determined by using a non-contact displacement gage, and the determination values have been used as data for analyzing tread wear characteristics of the tire or the like. As an apparatus for determining tire shapes as described above, a portable compact determination apparatus has been proposed in which a displacement gage (probe) scans a tire tread portion (for example, see Japanese Unexamined Patent Publication No. H5-256738).
However, in the portable determination apparatus reduced in weight, the weight of the displacement gage is relatively large. Therefore, when the displacement gage scans a tire tread portion, the position of the center of gravity of the whole determination apparatus shifts, resulting in a tilt of the determination apparatus and a change in the distance between the tread surface and the displacement gage. Accordingly, a problem arises that the determination accuracy is lowered. For this reason, the whole determination apparatus needs to be made heavy while resultantly sacrificing the lightness, or alternatively, a support needs to be provided to fix the determination apparatus. As a result, determination work requires large amounts of effort and time.

Method of and apparatus for determining tire shapes


A method and apparatus for transferring a message securely from a sender to a recipient over a network and includes at each transfer: creating a message; retrieving the public key of the recipient from an external key server just prior to sending the message; signing the message using the private key of the sender; encrypting the signed message using a public key encryption algorithm and the public key of the recipient producing an encrypted signed message; generating an E-mail message addressed to the recipient; attaching the encrypted signed message as an attachment to the E-mail message; and, transmitting the E-mail message to the recipient.

The invention relates generally to computing systems and more particularly to a method and system for providing secure data transmissions between Internet users.
The Internet is a global network of computers that uses a common communication protocol, the Transfer Control Protocol/Internet Protocol (TCP/IP), to transmit data from one location to another. Many application specific tasks, such as E-mail transmission and file transfer, are not directly supported by TCP/IP. Instead, support for these services is implemented by application specific protocols that in turn rely on TCP/IP for basic data transport services. One problem that is relatively unknown to individuals that make use of the Internet is the ease by which information can be obtained during transmission by unauthorized eavesdroppers. For example, most E-mail transmissions over the Internet are sent in cleartext. Cleartext is unencrypted data that can be intercepted anywhere along the path between a sender and the recipient.
Accordingly, sensitive business or personal information should not be transmitted in cleartext over the Internet. To do so is to risk its publication. To avoid this risk, sensitive data is often sent by courier services at great cost.
Encryption mechanisms can be used to ensure the integrity of information sent over the Internet. Two common encryption techniques, symmetric key encryption and public key encryption, are described below. In a symmetric key encryption, a unique key is identified and used by the sender to encrypt and by the receiver to decrypt a message. In public key encryption, separate keys are used to encrypt and to decrypt a message.
While secure communications are desirable, the mechanisms required to ensure security can be difficult to implement in a network environment. Private networks that include connections to public networks are often shielded using a firewall. A firewall provides a gateway between a public and a private network, or between public and private portions of a single network. A firewall can screen incoming and outgoing traffic to ensure integrity of the traffic between the two distinct domains. While the screening is desirable to avoid unauthorized access to or transfers of data, the additional security measures can have undesirable effects in limiting the kind or form of traffic that is able easily to be transmitted through the gateway.
In one aspect, the invention provides a method for transferring a message securely from a sender to a recipient over a network and includes at each transfer: creating a message; retrieving the public key of the recipient from an external key server just prior to sending the message; signing the message using the private key of the sender; encrypting the signed message using a public key encryption algorithm and the public key of the recipient producing an encrypted signed message; generating an E-mail message addressed to the recipient; attaching the encrypted signed message as an attachment to the E-mail message; and, transmitting the E-mail message to the recipient.
Aspects of the invention can include one or more of the following features. The step of retrieving the public key of the recipient can include verifying a status of a public key for the sender and where the external key server is operable to not return the recipient""s public key unless the status of the sender""s public key is active.
Verifying the status of a public key of the sender can include sending a hash of a sender""s public key to a external key server where the external key server is operable to maintain a status for each public key stored therein and enabled to return the status for a particular public key when the hash is received.
The external key server can be a single central key server. The external key server can be one of a group of external key servers each including a repository of public keys.
Substantially contemporaneous with sending the message, the method can include prompting the sender for a signature phrase, decrypting the private key of the sender using the signature phrase, applying a hash function to a sender""s public key to produce a hash and verifying a status of the sender""s public key including submitting the hash to the external key server to enable a look-up of a status of a public key of the sender.
The method can include designating a signature phrase by each user, either sender or recipient, encrypting a private key of the user using the signature phrase and storing the encrypted private key locally at a user""s computer.
The step of retrieving the public key of the recipient can include generating a request for a current public key of the recipient where the request can include an identifier for the recipient.
The identifier can be an E-mail address for the recipient or a hash of an E-mail address for the recipient.
The step of encrypting can include generating a random number, encrypting the message using the random number as a session key in a symmetric key encryption algorithm and encrypting the session key using a public key encryption algorithm and the public key of the recipient.
The step of signing a message can include decrypting a private key of the sender and applying a digital signature algorithm to the message using the sender""s private key.
The step of decrypting the private key can includes prompting the user for a signature phrase, applying a hash function to the signature phrase and decrypting the private key using a symmetric key encryption algorithm where the hash is used as the symmetric key.
The step of attaching the signed document can include designating a recipient""s E-mail address and the sender""s E-mail address, designating one or more of a public title and public message body for the E-mail message and attaching the encrypted signed message as an attachment to the E-mail message addressed to the recipient.
The step of transmitting can include transmitting the E-mail message to a forwarding proxy using a non-SMTP protocol where the forwarding proxy is operable to extract the E-mail message and forward the E-mail message to the recipient. The non-SMTP protocol can be the HTTP protocol.
The method can include creating an HTTP post including the E-mail message and transmitting the HTTP post. The forwarding proxy can forward the E-mail message by SMTP.
The method can include attaching a random number to the E-mail message prior to transferring where the forwarding proxy is operable to verify the random number is valid based on a predefined criterion, and if not, will not forward the E-mail message. The predefined criterion can be the passage of a predefined amount of time.
The method can include attaching a return receipt request to the E-mail message and acknowledging the return of a receipt including displaying the receipt to the sender. The opening of the E-mail message by the recipient can be conditioned upon the return of the return receipt.
The step of generating an E-mail message can include creating a MIME E-mail message addressed to the recipient. The step of attaching the signed document can include attaching the signed document to the MIME mail message as a MIME attachment. The step of transmitting can include sending the MIME mail message to the recipient.
The central key server can be one of a plurality of distributed key servers, each of which include public keys and status information to enable key retrieval from multiple locations, which facilitates secure transfers of messages between users.
In another aspect, the invention provides a method for transferring E-mail messages securely from a sender to a recipient over a network including, substantially contemporaneous with the transmission of a secure E-mail transmission from the sender to the recipient, retrieving the public key of the recipient from an external key server to ensure an active public key for the recipient is used in encrypting the message.
Aspects of the invention can include one or more of the following features. The step of retrieving can include verifying the status of a sender""s public key at the external key server to ensure the sender""s public key is available to allow for the authentication by the recipient of the E-mail message sent by the sender.
The step of retrieving can include retrieving a time stamp from the external key server. The time stamp can be signed by a public key of the external key server.
In another aspect, the invention provides a method for verifying the authenticity of a message received by a recipient process. The message is generated by a sender process and transferred using secure means over a network. The method includes decrypting a signed encrypted message exposing a message signed by the sender, verifying the sender""s signature, requesting a status for the sender""s public key from an external key server and displaying the status of the sender""s public key and the decrypted message.
Aspects of the invention can include one or more of the following features. The step of requesting a status for the sender""s public key from an external key server can includes receiving signed status information from the external key server. The method can further include verifying the external key server""s signature used to sign the status information.
The step of requesting a status for the sender""s public key from an external key server can include receiving unsigned status information from the external key server.
The step of requesting a status for the sender""s public key from an external key server can include receiving a time stamp certificate from the external key server.
The step of decrypting can include exposing a time stamp certificate signed by an external key server and associated with the signed encrypted message and verifying the external key server""s signature used to sign the time stamp certificate.
The step of displaying can include displaying the time stamp certificate.
The public key encryption algorithm can be selected so that encrypting processes are substantially faster than decrypting processes. The public key encryption algorithm can be a Rabin algorithm.
The step of displaying can include displaying two indicators and enabling an appropriate one of the two based on the status of the sender""s public key, either valid or invalid. The step of displaying can include displaying three or more indicators and enabling an appropriate one of the three based on the status of the sender""s public key, either valid, invalid or valid when signed but now invalid.
The step of decrypting a signed message can include recovering the recipient""s private key, applying a public key encryption algorithm to the encrypted session key included with the encrypted signed message to recover a session key and applying a symmetric key encryption algorithm to the encrypted signed message using the session key to recover the message.
Messages can be signed using a signature algorithm that is selected so that verifying a signature is substantially faster than signing a message. The signature algorithm can be a Rabin algorithm.
The step of recovering the private key can include prompting the user for a signature phrase, applying a hash function to the signature phrase and decrypting the private key using a symmetric key encryption algorithm where the hash is used as a session key. The step of applying a hash function can include applying the hash function to the signature phrase a large number of times, applying the hash function to the signature phrase approximately 5000 times, or applying multiple hash functions to the signature phrase.
The step of verifying a signature can include applying a hash function to a signed message resulting in a first hash and comparing the first hash with an associated second hash received from a signing party. The signing party can be the sender, the signed message can be the signed encrypted message and the second hash can be recovered when decrypting the signed encrypted message. The signing party can be the external key server, the signed message can be the time stamp certificate and the second hash can be recovered when decrypting the signed encrypted message. The signing party can be the external key server, the signed message can be the status information and the second hash can be generated by the external key server and provided along with the status information. The signing party can be the external key server, the signed message can be the recipient""s public key and the second hash can be recovered when decrypting the signed encrypted message.
Verifying the status of a public key of the sender can include sending a request to the external key server including an identifier designating the public key of the sender where the central key server is operable to maintain a status for each public key stored therein and enabled to return the status for a particular public key of the sender when the identifier is received.
In another aspect, the invention provides a method for transferring a message securely from a sender process to a recipient process over a network and includes creating a message and receiving the E-mail message. The step of creating includes retrieving a public key of the recipient and verifiable transmission time stamp where the transmission time stamp generated and signed by an external key server independent of the sender process, signing the encrypted message, encrypting the signed message using a public key encryption algorithm and the public key of the recipient and attaching the encrypted message to an E-mail message. The step of receiving the E-mail message includes decrypting the signed encrypted message, verifying the sender""s signature mathematically, requesting a status for the sender""s public key from an external key server including receiving signed status information, verifying the external server""s signature that signed the status information and displaying the status of the sender""s public key, the time stamp certificate and the decrypted message.
In another aspect, the invention provides a method for securely transferring a message from a sender to a recipient over a network and includes creating a message, retrieving the public key of the recipient from an external key server, encrypting the message using a public key encryption algorithm and the public key of the recipient producing an encrypted message and transmitting the E-mail message to a forwarding proxy using a non-SMTP protocol where the forwarding proxy is operable to extract the E-mail message and forward the E-mail message to the recipient.
Aspects of the invention can include one or more of the following features. The non-SMTP protocol can be the HTTP protocol. The method can include creating an HTTP post including the E-mail message and transmitting the HTTP post. The forwarding proxy can forward the E-mail message by SMTP.
In another aspect, the invention provides, in a public key encryption system that includes a central key repository and a plurality of users, where a user""s public key is stored at the central key repository and the user""s associated private key is stored locally on a user""s computer, a method for recovering lost keys including designating an recovery question and an answer to the recovery question, encrypting the user""s private key using a first hash of the answer as a session key in a symmetric key encryption process, taking a different hash of the answer producing a second hash and storing the second hash and the recovery question at the central key repository. When prompted by the user to recover a lost private key, the method includes prompting the user to provide the answer, taking the different hash of the answer provided producing a third hash and transmitting the third hash to the central key repository without transmitting the answer itself and comparing the second and third hashes. If they match, the encrypted private key is returned to the user and the private key is decrypted using the first hash and stored.
In another aspect, the invention provides an apparatus for creating and viewing secure messages transferred over a network between one or more senders and recipients. The apparatus includes a composer viewer operable to compose a message, retrieve a public key and public key status for a recipient of the message, verify an active status of a sender""s public key, encrypt the message and view secure messages received from other senders, and a communication process for transferring composed messages out from the sender and for receiving composed messages from other senders.
Aspects of the invention can include one or more of the following features. The composer viewer can be operable to retrieve the public key and public key status just prior to the transfer of the message to the recipient.
The composer viewer can be operable to retrieve a time stamp certificate that certifies the sender""s identity, the recipient""s identity, the integrity of the message, and the time that the message was sent.
In another aspect, the invention provides, in a public key encryption system that includes a central key repository and a plurality of users, where a user""s public key is stored at the central key repository and the user""s associated private key is stored locally on a user""s computer, and where messages are signed by a private key of the central key repository and can be verified by retrieving an associated public key for and from the central key repository, a method for certifying a document sent from the central key server is valid. The method includes creating a key server certificate including applying a signature operation to the public key of the central key repository using a verifiable private key of the central key repository, attaching the key server certificate to a document that is to be transferred to a user and needs to be certified, producing a certified document, and signing the certified document including applying a signature operation on the certified document using the public key of the central key repository.
In another aspect, the invention provides, in a public key encryption system that includes a central key repository, a plurality of users and a trusted third party server, where a user""s public key is stored at the central key repository and the user""s associated private key is stored locally on a user""s computer, and where an encrypted version of a user""s private key is stored by the trusted third party server for the benefit of beneficiary of the escrow process, a method for verifying the private key escrowed at the trusted third party server is same as the private key stored locally by a user without exposing the private key to the central key repository. The method includes, at the trusted third party server and prior to storing the user""s private key, taking a hash of the private key producing a first hash, encrypting the private key using the public key of the escrow beneficiary, and storing the private key and returning the first hash to the user. At the user and prior to storing the user""s private key locally, the method includes taking a hash of the private key producing a second hash, comparing the first and second hashes and, if the hashes match, storing the public key associated with the private key locally on the user""s computer.
In another aspect, the invention provides an apparatus for transferring a message securely from a sender to a recipient over a network including a composer operable to create a message and retrieve a public key of the recipient from an external key server just prior to sending the message, a signature engine operable to sign the message using the private key of the sender, an encryption engine operable to encrypt the signed message using a public key encryption algorithm and the public key of the recipient producing an encrypted signed message, and a wrapping application operable to generate an E-mail message addressed to the recipient, attach the encrypted signed message as an attachment to the E-mail message and transmit the E-mail message to the recipient.
In another aspect, the invention provides an apparatus for verifying the authenticity of a message received by a recipient process where the message is generated by a sender process and transferred using secure means over a network. The apparatus includes a decryption engine for decrypting a signed encrypted message exposing a message signed by the sender, a verification engine operable to verify the sender""s signature, request a status for the sender""s public key from an external key server, receive status information from the external key server and verify the external key server""s signature used to sign the status information and a display engine operable to display the status of the sender""s public key and the decrypted message.
In another aspect, the invention provides an apparatus for securely transferring a message from a sender to a recipient over a network including a composer operable to create a message and retrieve the public key of the recipient from an external key server, an encryption engine for encrypting the message using a public key encryption algorithm and the public key of the recipient producing an encrypted message and a transmission system separable from the composer and operable to transmit the E-mail message to a forwarding proxy using a non-SMTP protocol where the forwarding proxy is operable to extract the E-mail message and forward the E-mail message to the recipient.
In another aspect, the invention provides a method for posting a public key for a user at central key server where the public key is retrievable by a sender and used by a public key encryption process executed at the sender""s computer to securely transfer a message from a sender to a recipient over a network. The method of posting includes generating a set of public and private keys, associating a unique E-mail address for the user with the set of public and private keys, storing the encrypted private key locally on the user""s computer; and posting the public key including storing the public key at the central key server in a key list.
Aspects of the invention can include one or more of the following features. The key list can be indexed by the E-mail address or a hash of the E-mail address. The method can include designating a signature phrase where the signature phrase is used by the user""s computer to encrypt the private key.
In another aspect, the invention provides a method for producing a set of public and private keys for a user where the public key is retrievable by a sender and used by a public key encryption process executed at the sender""s computer to securely transfer a message from a sender to a recipient over a network. The method includes generating a large random number having a first size including generating a first random number at the user""s computer and second random number at the central key server and mixing the first and second random numbers, using the large random number as a seed to generate two large prime numbers that form the user""s private key, multiplying the two large prime numbers to produce a public key having a second size that is comparable to the first size and posting the public key at the central key server.
In another aspect the invention provides a method for producing a large random number used as a seed in generating a secure set of public and private keys for a user, where the public key includes a first size. The method includes generating a first random number at the user""s computer, generating a second random number at a central key server and mixing the first and second random numbers to produce the large random number where that large random number has a second size that is comparable to the first size.
In another aspect, the invention provides a method for posting a public key for a user at a central key server where the public key is retrievable by a sender and used by a public key encryption process executed at the sender""s computer to securely transfer a message from a sender to a recipient over a network. The method of posting includes generating a set of public and private keys, associating an E-mail address for the user with the set of public and private keys, escrowing the private key including retrieving a public key package for the central key server where the public key package includes a public key of a trusted third party, encrypting the private key with the public key of the trusted third party and sending the encrypted private key and public key to the central key server to be forwarded to the trusted third party for escrowing.
If the escrowing at the trusted third party is successful, a hash of the private key is received back from the trusted third party. The private key is hashed and compared with the hash received and, if they match, the private key is stored locally at the user""s computer. The method include receiving an E-mail confirmation request from the central key server at the E-mail address indicating that the escrowing process was successful and sending a confirmation to the central key server which, upon receipt, will cause the central key server to post the public key.
In another aspect, the invention provides a method of escrowing a set of public and private keys including generating a set of public and private keys, associating an E-mail address for the user with the set of public and private keys, escrowing the private key with a trusted third party including encrypting the private key and sending the encrypted private key to the trusted third party, receiving a successful escrow message from the trusted third party and verifying a private key escrowed by the trusted third party is the same is as the private key.
Aspects of the invention can include one or more of the following features. The method can include receiving a hash of the private key back from the trusted third party, hashing the private key and comparing the two hashes and if they match storing the private key locally at the user""s computer.
The method can include receiving a confirmation request from the central key server at the E-mail address indicating that the escrowing process was successful and sending a confirmation to the central key server which, upon receipt, will cause the central key server to post the public key.
In another aspect, the invention provides a method for authenticating a message sent from a sender to a recipient over a network including generating a time stamp request including the message, sending to a time stamping authority the time stamp request, constructing a time stamp certificate comprising the message to be sent and the current time, returning the time stamp certificate to the sender and attaching the time stamp certificate to the message and sending the message to the recipient.
Aspects of the invention can include one or more of the following features. The time stamp request can include a hash of the message to be sent and the sender""s and the recipient""s E-mail addresses, the hash of the sender""s and recipient""s E-mail address, a hash of the message to be sent and the sender""s and the recipient""s E-mail addresses, the hash of the sender""s and recipient""s E-mail address, a hash of sender""s public key and a status of the public key, or a hash of recipient""s public key and a status of the public key.
The method can include signing the time stamp certificate with a private key of the time stamping authority.
In another aspect, the invention provides a method for authenticating a sender, a recipient and a message when transferring the message from the sender to the recipient over a network including generating, remotely from the sender, a time stamp certificate that includes the message, a time stamp, the recipient""s and sender""s public keys and recipient""s and sender""s public key status, attaching the time stamp certificate to the message and sending the message and the time stamp certificate to the recipient.
Aspects of the invention can include one or more of the following features. The time stamp certificate can include a hash of the message, the hash of the recipient""s public key, the hash of the sender""s public key the sender""s and the recipient""s E-mail addresses, a hash of the sender""s and the recipient""s E-mail addresses
Implementations of the invention can include one or more of the following advantages. Documents can be encrypted by the intended recipient""s public key and signed with a signature that includes a remotely generated and signed time stamp provided from a central server. The remotely generated time stamp can be evaluated to verify the time of signing. The remotely generated time stamp can be in the form of a certificate that can be used to authenticate the sender""s and recipient""s public keys. Care is taken in the construction of the time stamp so that it cannot be tampered with or attached to other documents. The present invention provides an easy means for revoking a signature that assures both the sender and the recipient of the authenticity of each signature produced. A screening mechanism is provided that can alert a recipient to both invalid signatures as well as out of date signatures. A sender can be required to validate his/her own signature when sending a transmission (E-mail), thereby further ensuring the authenticity of each message transmitted. A public key retrieval is completed at each message transmission ensuring that the correct public key is retrieved for the recipient each time a message is sent. An algorithm that is optimized to minimize the amount of time required to encrypt messages is provided. The present invention provides verification of signature status similar to a certificate, but with the additional feature of public key validation at verification time.
A system is provided for secure E-mail services. Secure E-mail messages can be composed or generated using the secure massaging system, the result of which can be attached as a MIME message to a conventional E-mail message for transfer to a recipient. A viewer or reader is provided for opening the secure MIME attachment at a recipient device and for decrypting the underlying contents.
The secure MIME attachment can be sent directly by the composer, such in an SMTP message format, or attached and sent using a conventional E-mail program. While one implementation of the invention requires the client sender to have access to an SMTP server, an alternative implementation sends the secure message with an HTTP post. A forwarding proxy or relay is used to recover the secure message from the HTTP post and to forward the message as an attachment to a conventional E-mail message or as an SMTP message.
These and other advantages of the present invention will become apparent from the following description and from the claims.


A snow scraper includes transparent main body with a hand grip portion and a blade formed on one end of the hand grip portion. The blade has a front portion which is provided with an inclined shoveling edge and a plurality of claws. The snow scraper further has a pressure indicating unit, a tire tread measuring unit and a light bulb unit and a magnifying glass.

1. Field of the Invention
The invention relates to a snow scraper, more particularly to a multi-purpose snow scraper for a car.
2. Description of the Related Art
FIG. 1 shows a conventional snow scraper which is used to scrape the snow that gathers around the wheels of a car. As best illustrated, the scraper includes a hand grip portion (91) and a blade (92) which is disposed on one end of the hand grip portion (91). The blade (92) has a front portion that is provided an oblique edge (921) for shoveling the snow and a plurality of claws (922) for scrubbing the snow from the wheels.
As a precautionary measure, a driver must check the pressure in the tire and the depth of the tread on the tire in order to prevent any unfortunate accident from happening due to insufficient tire pressure and wearing of the tire. If the checking operation is carried out at night, a torch light becomes a necessary tool. In order to facilitate the removal of snow and the conduction of the checking operation, the scraper, the pressure indicating unit, the tread depth measuring rod and the torch light are indispensable. All of these instruments would occupy a lot of space in the car, and misplacement or lack of one of the above-mentioned instruments would hinder the snow removing and checking operations.


A cavity is formed in the floor of a building for receiving the floor type advertising apparatus. A lower holding layer of magnetic material having an opening formed therethrough is located and secured in the lower portion of the cavity. An upper holding layer of magnetic material having an opening formed therethrough is attached to the lower side of a transparent layer and both the transparent layer and the upper holding layer are located in the cavity to allow the magnetic lines of force from the holding layers to removably secure the transparent layer and the upper holding layer to the lower holding layer in the cavity. A support layer is secured to the floor of the cavity within the opening of the lower holding layer for supporting an advertising layer. One side edge of the upper holding layer is bonded to one side edge of the lower holding layer whereby the other side edge of the upper holding layer with the transparent layer may be lifted from the lower holding layer and folded back to allow insertion or removal of the advertising layer.

1. Field of the Invention
The invention relates to the use of magnetic material to secure advertising medium in a cavity in a floor.
2. Description of the Prior Art
Magnetic material has been used for attaching advertising signs or information to metal doors. The known devices are either sheets of magnetic material having the sign incorporated thereon or the use of individual magnets for holding paper or the like to a door. These devices, however, project outward from the door and are not suitable for use for floor advertisement purposes on floors subject to foot traffic. Moreover, a sheet of magnetic material having a sign incorporated therein is a custom type single purpose system and is too expensive for advertisement purposes where the advertisement is changed often.
U.S. Pat. No. 4,907,361 discloses a ground advertising panel which appears to be complicated and expensive.


An eye protection device against broadband high intensity light sources, including a fast response component (picosecond to microsecond) and a slow response component (microsecond and longer). The fast response component consists of two thin semiconductor layers "sandwiched" between two transparent electrodes. The natures and dimensions of the semiconductor layers and the voltage bias applied to them are determined such that enough photo-excited electrons are generated in the first small bandgap layer so that the second large bandgap layer undergoes a rapid insulator-to-metal transition at the light-intensity threshold for eye damage. Upon becoming metal-like, this layer blocks the incident light. Below the damage threshold, the fast response component is transparent. The slow response component includes a PLZT (lanthanum-modified lead zirconium titanate) or similar electro-optic shutter. This component is transparent below the damage threshold. Finally, ballistic and chemical protection are obtained by embedding these slow and fast response components in a suitable plastic goggle.

The present invention relates to eye protection devices for preventing eye injuries due to incident broadband, high intensity light, and more particularly to such a device which is normally transparent, yet which becomes opaque within a few nanoseconds when irradiated by high intensity light over a broad band of wavelengths.
Military applications of single wavelength and tunable wavelength lasers operating in the visible (400-700 nm) and near-infrared (700-1200 nm) spectral regions are increasing rapidly. Consequently, the protection of the eyesight of military personnel against high intensity laser light from hostile and friendly forces is a major concern. A desirable protective device would be a goggle with the following major features. First, the goggle should be transparent over a broad wavelength range, unless irradiated at a light intensity above the threshold for eye damage. Second, the goggle should block the incident light a few nanoseconds after being irradiated above the damage threshold. Third, the goggle should provide ballistic and chemical protection.
At present, there is no eye protection device against high intensity light sources which (1) is transparent over a broad wavelength range, unless irradiated at a light intensity above the threshold for eye damage, and (2) becomes opaque within a few nanoseconds for intensities exceeding the threshold intensity for a broad band of wavelengths.
Devices have been developed to protect against high intensity light like a nuclear flash. However, none of these device are both (1) transparent over a broad wavelength range below the eye damage threshold, and (20 become opaque within a few nanoseconds for intensities exceeding the threshold for a broadband of wavelengths. A table of developed or potential devices, their response times, and their capability to offer broadband protection is given below.
__________________________________________________________________________ Approximate Response Development Device Time (sec) Broadband Stage __________________________________________________________________________ Liquid crystal .about.10.sup.-3 Yes Developed. light value PLZT or other >10.sup.-6 Yes Developed. ferro-electric electro-optic shutter Image converter >10.sup.-6 Yes Developed. Awkward for a foot soldier. Holographic 10.sup.-12 -10.sup.9 No Developed. Diffraction Optics Photochromic >10.sup.-8 Yes Potential. Difficult to simultaneously transmit and protect against visible light. Electrochromic >10.sup.-9 Yes Potential. High Effect fields (10.sup.6 -10.sup.7) required. Semiconductor >10.sup.-9 Yes (IR & Near Potential. Metal VO.sub.2 Light IR) (Visible) Valve Non-Linear >10.sup.-12 > 10.sup.-9 Yes Potential. Requires Optical much higher light Phenomena intensities than the damage threshold, or an awkward focussing assembly. __________________________________________________________________________
In summary, the developed broadband devices do not have fast enough response times. The proposed devices may be capable of fast response times, but have the indicated problems regarding their development.
It is therefore an object of the invention to provide an eye protection device which is transparent over a broad wavelength range until irradiated at a light intensity above the threshold for eye damage, and which becomes opaque within a few nanoseconds for incident light intensities exceeding the threshold intensity for a broad band of wavelengths.

Eye protection device against broadband high intensity light


A wind turbine having a generator for generating electrical energy and a transformer is disclosed. The transformer is designed to receive electrical energy from the generator on a secondary side and to discharge said electrical energy again on a primary side at a higher voltage. The wind turbine also comprises a temperature monitoring means for the transformer. The voltage supply to the temperature monitoring means is fed from the primary side of the transformer. The temperature monitoring means is thereby independent of the control system of the wind turbine. The temperature monitoring means reduces the risk of the transformer overheating. A method for operating such a wind turbine is also disclosed.

Conventionally, the control system for the wind energy installation is responsible for monitoring the temperature of the transformer. Information about the temperature of the transformer is processed in the control system. If the temperature exceeds predefined limit values, the control system initiates suitable countermeasures. For example, a cooling means may be put into operation or the transformer may be isolated from the mains. This temperature monitoring is dependent on the control system of the wind energy installation being in operation.

Wind energy installation and method for operating a wind energy installation with temperature monitoring for the transformer


Disclosed are methods for deposition of improved memory element films for semiconductor devices. The methods involve providing a hard mask over an upper surface of a metal line of a semiconductor substrate where vias are to be placed, recess etching the mask substantially in all upper surfaces except where vias are to be placed, depositing a Ta-containing capping layer over substantially all the metal line surfaces except the surface where vias are to be placed, polishing the Ta-containing capping layer to produce a damascened Ta-containing cap while exposing the metal line at the via forming surface, depositing a dielectric layer, patterning the dielectric layer to form a via, and depositing memory element films. The improved Ta—Cu interface of the subject invention mitigates and/or eliminates lateral growth of memory element films and copper voiding under the dielectric layer at the top surface of the metal line, and thereby enhances reliability and performance of semiconductor devices.

The basic functions of a computer and memory devices include information processing and storage. In typical computer systems, these arithmetic, logic, and memory operations are performed by devices that are capable of reversibly switching between two states often referred to as "0" and "1." Such switching devices are fabricated from semiconducting devices that perform these various functions and are capable of switching between two states at high speed. Electronic addressing or logic devices, for instance, for storage or processing of data, are made with inorganic solid state technology, and particularly crystalline silicon devices.
Much of the progress in making computers and memory devices faster, smaller and less expensive involves integration, squeezing ever more transistors and other electronic structures onto a postage stamp sized piece of silicon. A postage stamp sized piece of silicon may contain tens of millions of transistors, each transistor as small as a few hundred nanometers. The escalating requirements for high density and performance associated with ultra large-scale integration require responsive changes in semiconductor technology.
In recent years copper (Cu) has emerged as an alternative to aluminum (Al) for metallization patterns, particularly for interconnect systems having smaller dimensions. Despite the beneficial properties of copper, copper usage in large scale semiconductor manufacturing raises some concerns which need to be addressed. For example, copper interconnects affect memory element film deposition and thereby, influence performance of semiconductor devices.

Use of Ta-capped metal line to improve formation of memory element films


A method for efficiently storing data into a data storage system containing parity data comprises the steps of: determining the data storage units and the portions of each data storage unit where the data will be stored; determining the number of times the data units are accessed to calculate parity data for the new data, to store the new data, and to store the parity data using the complementary mode; determining the number of times the data units are accessed to calculate parity data for the new data, to store the new data, and to store the parity data using the noncomplementary mode; comparing the number times the data units are accessed using the complementary mode to the number of times the data units are accessed using the noncomplementary mode; calculating the parity data with the mode that requires the fewest number of accesses; and storing the calculated parity data and the new data in the data storage units. Thereby, the present invention minimizes the number of times the disk must be accessed to calculate parity.

1. Field of the Invention
The present invention relates to a method of processing stored data containing parity data, and more particularly, to a method of storage management that allows data and its associated parity data to be written more quickly.
2. Description of the Prior Art
In current computer systems, central processing units (CPU) are attaining higher speeds for better system performance. However, when a CPU has to access data from a peripheral device such as a hard disk, this input/output (I/O) process seriously affects system performance because it requires mechanical motion such as moving the magnetic heads as data is being stored/read on the hard disk.
To eliminate the disadvantageous effect of accessing data on a hard disk, the conventional practice is to store data on multiple magnetic disks known as disk arrays. The use of a disk array increases the input/output bandwidth and improves the input/output performance.
To secure the integrity of the data stored in such multiple disk systems, a redundant magnetic disk is commonly added to the disk array in order to store parity data. This arrangement allows the integrity of the stored data to be enhanced without the need for a single, large and more expensive disk. This type of system is referred to as Redundant Arrays of Inexpensive Disks (RAID).
In RAID systems, there is a distinction made among grades, based on differences in performance. For example, in the RAID4 arrangement shown in FIG. 1, there are five magnetic disks D0, D1, D2, D3, and D4. Magnetic disk D0 is dedicated to storing the parity data P00, P10, P20, P30, and P40 associated with the data stored in disks D0, . . . , D4. The parity data P00-P40 stored in sectors S0-S4 is obtained by executing an Exclusive-Or operation (indicated here by the symbol "+") between the data located in each of the remaining disks D1, . . . , D4 which is associated with a given storage sector. In other words, where DATAsd represents the Data in Sector s of disk d, and Psd represents the parity data for sector s which is stored on disk d,
P00=DATA01+DATA02+DATA03+DATA04;
P10=DATA11+DATA12+DATA13+DATA14;
P20=DATA21+DATA22+DATA23+DATA24;
P30=DATA31+DATA32+DATA33+DATA34; and
P40=DATA41+DATA42+DATA43+DATA44.
If a block of data in a storage sector SO is erased, then the erased data can be restored by performing an Exclusive-Or operation between the remaining data located on the same sector of the other disks and the parity data associated with that storage sector. For example, if DATA02 on disk D2 is erased, it may be recovered by performing an Exclusive-Or operation on the remaining data DATA01, DATA03, and DATA04, and the parity data P00 which is associated with sector S0. This may be shown as follows:
______________________________________ P00 + (DATA01 + DATA03 + DATA04) = (DATA01 + DATA02 + DATA03 + DATA04) + (DATA01 + DATA03 + DATA04) = DATA02 ______________________________________
In the above-mentioned RAID4 system it is possible, within a very short time, to modify data on the same sector of different disks, such as DATA01 and DATA03 which are in one storage sector, S0, and also to modify data, such as DATA14, in another storage sector, S1. Because the data in this example DATA01, DATA03, DATA14 is stored separately on different magnetic disks D1, D3, D4, it is possible to almost simultaneously modify the above-mentioned data, without requiring a wait state for moving the magnetic head several times and for other mechanical motions which would be required if the data were all stored on a single larger disk.
As shown in FIG. 1, when modifying the data in storage sectors S0 and S1, the related parity data P00 and P10, respectively, should also be modified in order to maintain data integrity. However, since the two sectors of parity data, P00 and P10, are within the same magnetic disk D0 as one another, a wait state is required for moving the magnetic head and for other mechanical motions of the magnetic disk D0.
FIG. 2A shows the RAID5 system. It differs from the RAID4 system in that the parity data is sequentially distributed in each magnetic disk. Thus, it is possible to almost simultaneously modify data in most storage locations during a request. Since the parity data P00, P11, P22, P33, P44 is not located in one magnetic disk, it is possible to save the wait state for the time formerly spent in moving the magnetic head and in other mechanical motions of the disk. Therefore, RAID5 has higher system efficiency than that of RAID4. Examples of RAID systems are described in "DISK SYSTEM ARCHITECTURES FOR HIGH PERFORMANCE COMPUTING", Randy H. Katz, Garth A. Gibson, and David A. Patterson, IEEE: PROCEEDINGS OF THE IEEE, VOL. 77, NO. 12, DECEMBER 1989, which is incorporated herein by reference.
From the above descriptions of the conventional techniques, the key factor affecting system performance is the wait state associated with mechanical motions during the accessing of magnetic disks. Therefore, if the number of times that the magnetic disk is accessed can be reduced, the overall system performance can be improved.
Consequently, there is a need for a method for writing the data to the magnetic disks faster by reducing the magnetic disk access time.

Method of processing stored data containing parity data


A power supply with dimming control for a high-power DC LED lamp is provided. Particularly, a variable resistor is provided to a circuit of the high-power DC LED lamp for changing a current supplied to a light-emitting unit of the high-power DC LED lamp, thereby adjusting luminance (brightness) and power consumption (consumed watts) of the high-power DC LED unit of the high-power DC LED lamp. The variable resistor is provided to a driver, transformer, adaptor or power supply of the high-power DC LED lamp in a built-in manner or a remotely connected manner.

1. Technical Field
The present invention relates to a power supply with dimming control for high-power DC LED lamps. More particularly, the power supply is capable of adjusting luminance (brightness) and power consumption (consumed watts) of a light-emitting unit in a conventional high-power DC LED lamp, and is applicable to dimming control of one or more sets of such high-power DC LED units.
2. Description of Related Art
Referring to FIG. 1, FIG. 4, FIG. 6 and FIG. 8, in the case of average halogen lamps and tungsten filament lamps (incandescent lamps), the dimming control is achieved by changing the voltage or current of a transformer 1 in the lamp. However, to a lamp with a high-power DC LED unit 41, by changing the voltage or current at the input end of its driver 2 is not effective to get significant dimming effects (only a variation about 10%-20%), and doing so can bring additional burdens to the power supply of the high-power DC LED lamp, leading to decreased stability and service life of the lamp. This is because the driver 2 typically provided in such a high-power DC LED lamp offsets the change of the voltage or current made at the input end of the driver 2, so the conventional means for dimming control by changing the voltage or current is inadequate for the light-emitting unit of a high-power DC LED lamp.
In the current technology, there is no way to perform dimming control of the high-power DC LED unit 41 of a high-power DC LED lamp by adjusting a transformer, an adapter/power supply 1, a driver 2 in the burner/bulb or a conventional dimmer.
Therefore, the existing high-power DC LED lamp 4 fails to have dimming control and can be only operated between "on" and "off" and the lack of dimming control weakens the practicability of the existing device.

Power supply with dimming control for high-power DC LED lamp


An access point (AP) in a wireless local area network (WLAN) uses a protocol to determine frequency/time resource allocations of resource units (RUs) in parallel with data transfer to and from WLAN stations (STAs). The AP generates a sounding table associating STAs with RUs for uplink (UL) and downlink (DL). The AP processes the sounding table to create a channel map table and then the AP allocates particular RUs to particular STAs. The STAs then receive and transmit data from and to the AP over the allocated RUs. This approach achieves good throughput while reducing the use of signaling and pilot overhead associated with channel sounding. To avoid interruption of ongoing transmissions, a newly arriving STA is grouped and sounded with other STAs. The protocol includes a joint sounding and data epoch followed by a determination of the channel map table.

IEEE 802.11ac provides an arrangement for channel estimation of the multiple downlink channels from an AP to multiple STAs. The channel estimation involves a process called sounding. Various schemes can be used to perform sounding. For example, an AP can transmit a Null Data Packet-Announcement (NDP-A). The NDP-A contains the addresses of particular STAs to which the AP wishes to transmit data. The NDP-A is followed by a Null Data Packet (NDP). The NDP represents pilot energy; that is, a pre-defined pattern. Each STA addressed by the NDP-A measures the downlink wireless channel from the AP to itself. The channel measurement is possible because the given STA knows the pre-defined pattern and can estimate the effects of the channel on that pattern (for example, amplitude attenuation, carrier phase rotation, and time delay). The various STAs feedback their channel measurements, and then the AP has knowledge of the wireless channels from the AP to the STAs.
However, NDP-A and NDP messages and similar sounding management and pilot messages create an overhead. That is, these sounding-specific messages consume both bandwidth and energy. There is a tradeoff between placing energy into pilot signals and placing that energy into medium access control (MAC) data frames. For a shared medium every transmission of energy is potentially communication-limiting to some other unrelated simultaneous transmission.

Wireless local area network sounding protocol


A depilatory device includes a flexible plastic cylindrical member formed with a plurality of circumferentially-extending slits, the plastic member being rotated about its longitudinal axis while supported in an arcuate position such that the slits open and close during rotation of the plastic member to receive and pluck the hairs. The plastic member includes a high-strength flexible core imparting mechanical strength, and the slits are formed with corrugated or otherwise non-planar faces to enhance their gripping power when the slits are closed.

The present invention relates to depilatory devices, and also to hair-plucker bodies used in such devices, and particularly to improvements in or modifications to the depilatory devices described in U.S. Pat. Nos. 4,726,375 and 4,807,624.
U.S. Pat. No. 4,726,375 describes a depilatory device for removing body hair, comprising a manually-grippable housing, and a hair-plucker body rotatably mounted to the housing and having an exposed section formed with a plurality of gaps in its outer surface which open and close during the rotation of the hair-plucker body to receive, pluck, and eject body hair growing on a surface over which the hair-plucker body is moved. The hair-plucker body is a flexible cylindrical member of plastic (preferably elastomeric) material having a smooth outer surface formed with a plurality of slits penetrating only partially through the plastic member and extending circumferentially thereof. The plastic member is rotated about its longitudinal axis and is supported in an arcuate position such that the slits open at the convex side of the plastic member during its rotation to receive hairs between the open confronting faces of the slits, and close at the concave side to clamp the hairs between the closed confronting faces of the slits.

Depilatory device and hair-plucker body for use therein


Methods and devices are provided for determining the status of a networked device. Messages from such devices may include information indicating the health, accuracy and/or reliability of a device and/or of the network that includes the device. Multiple message formats may be supported, e.g., heartbeat only, partial statistics, full statistics, etc. Transmission of such messages may be triggered by the occurrence of various conditions, such as the passage of a predetermined time interval, a predetermined change in one or more criteria, etc. In some implementations, a time-based message throttle establishes a minimum time interval between messages. Messages may be created in a format that is compatible with SNMP. Messages may be transmitted in more than one packet, if necessary. Messages may be sent to one or more devices, e.g., to one or more servers, according to various criteria.

1. Field of the Invention
The present invention relates methods and devices for monitoring the status of networked devices. More particularly, the present invention relates to monitoring the status of relatively unsophisticated devices, such as radio frequency identification ("RFID") devices, in a network.
2. Description of the Related Art
"Smart labels," generally implemented by RFID tags, have been developed in an effort to address the shortcomings of bar codes and add greater functionality. RFID tags have been used to keep track of items such as airline baggage, items of clothing in a retail environment, cows and highway tolls. As shown in FIG. 1, an RFID tag 100 includes microprocessor 105 and antenna 110. In this example, RFID tag 100 is powered by a magnetic field 145 generated by an RFID reader 125. The tag's antenna 110 picks up the magnetic signal 145. RFID tag 100 modulates the signal 145 according to information coded in the tag and transmits the modulated signal 155 to the RFID reader 125.
RFID tags use the Electronic Product Code ("EPC" or "ePC") format for encoding information. An EPC code includes variable length bits of information (common formats are 64, 96 and 128 bits), which allows for identification of individual products as well as associated information. As shown in FIG. 1, EPC 120 includes header 130, EPC Manager field 140, Object class field 150 and serial number field 160. EPC Manager field 140 contains manufacturer information. Object class field 150 includes a product's stock-keeping unit ("SKU") number. Serial number field 160 is a 40-bit field that can uniquely identify the specific instance of an individual product i.e., not just a make or model, but also down to a specific "serial number" of a make and model.
In theory, RFID tags and associated RFID devices (such as RFID readers and printers) could form part of a network for tracking a product (or a group of products) and its history. However, various difficulties have prevented this theory from being realized. One problem that has required considerable time and energy from RF engineers is the development of lower-cost RFID tags with acceptable performance levels.
In part because of the significant efforts that have been expended in solving the foregoing problems, prior art systems and methods for networking RFID devices are rather primitive. RFID devices have only recently been deployed with network interfaces. Prior art RFID devices and systems are not suitable for large-scale deployment of networks of RFID devices.
Conventional RFID devices also have a small amount of available memory. A typical RFID device may have approximately 0.5 Mb of flash memory and a total of 1 Mb of overall memory. The small memories of RFID devices place restrictions on the range of possible solutions to the problems noted herein. In addition, an RFID device typically uses a proprietary operating system, e.g., of the manufacturer of the microprocessor(s) used in the RFID device.
RFID devices do not currently achieve reliability levels required of customers. Moreover, many RFID devices are deployed in a hostile industrial environment (such as a warehouse or factory) by relatively unskilled "IT" personnel. RFID devices may be used intermittently or infrequently. However, when an RFID device is needed it must perform immediately or significant delays may ensue. These delays may affect an entire supply chain and could result in significant costs.
One established method of determining the status of networked devices is actively polling each device. In part because of the bandwidth consumed by the polling process, this is not a desirable method for networks involving large numbers of devices.
The proposals currently being considered for implementation by EPCGlobal, the de facto standards body for RFID networking, call for the use of the Simple Network Management Protocol ("SNMP") for device management. SNMP allows for "trap" generation when an exceptional situation occurs. However, SNMP traps are not intended for routine status reporting. Such use would be considered an abuse of SNMP and would not be well accepted by other standards bodies.
Therefore, it would be desirable to provide methods for ensuring that specific RFID devices, or similarly unsophisticated devices in a network, are healthy and operational. It would also be desirable to detect, diagnose and correct incipient device problems before such problems reach critical levels and/or require device replacement. Moreover, it would be desirable to implement such methods without having to actively "poll" such devices.

This patent is subject to a terminal disclaimer.

Using syslog and SNMP for scalable monitoring of networked devices


According to an embodiment, an apparatus includes a first detector, a second detector, and a controller. The first detector is configured to detect first radiation at a first frequency within a first time by at least a first radiation detecting element and a second radiation detecting element that are positioned near to each other, and output a first signal. The second detector is configured to detect second radiation at a second frequency less than the first frequency within a second time by at least the first radiation detecting element and the second radiation detecting element, and output a second signal. The controller is configured to generate a third signal representing a difference between the first signal and the second signal, and calculate energy using the third signal.

Known today are photon-counting computed tomography (CT) devices using a photon-counting radiation detector (hereinafter, simply referred to as a detector). Unlike integrating detectors, photon-counting detectors output signals from which each of the X-ray photons having passed through a subject can be counted. In other words, a photon-counting detector outputs a pulse signal representative of a radioactive ray being incident on the detector, and with a waveform having a pulse height proportional to the radioactive energy. The detector can therefore estimate the radioactive energy incident on the detector by analyzing the pulse waveform. A photon counting CT device is therefore capable of reconstructing an X-ray CT image with a high signal-to-noise (SN) ratio.
The signals output from the photon-counting detector can also be used in measuring (separating) the energies of the X-ray photons. The photon counting CT device is therefore capable of visualizing a plurality of separate energy components from a piece of projection data collected from X-ray radiation at one tube voltage.
Required to enable the detector to distinguish subject materials from one another by measuring the energies of the X-ray photons having passed through the materials is calibration of the detector in a relation between detector outputs and energies of the fluorescent X-rays (incident energies) that are incident on the detector. In other words, when the detector is what is called an indirect conversion detector, detectors have variations in the characteristics of the silicon photomultiplier (SiPM) device (such as the multiplication factor and the operating temperature), and variations in the detection efficiency of scintillation light (variations in the detector geometric structure), and therefore, calibration of the detector outputs with respect to incident energies is required. The indirect conversion detector is a detector that converts incident X-ray photons into scintillation photons using a scintillator, amplifies the scintillation photons with the SiPM, and outputs the result.
In the energy calibration of photon-counting detectors, a standard source such as checking source or a radioisotope (RI) is often used. However, a checking source or an RI has limited radioactivity. When a detector is calibrated by placing a standard source with a radioactivity of several maga-becquerels to giga-becquerels and requiring strict management at a position approximately 1 meter away from the detector, a dose of radioactive rays being incident on each detecting element, which has a size of 1 millimeter by 1 millimeter, for example, is reduced prominently to a level of several becquerels to several-thousands becquerels. It is therefore infeasible to use a standard source in the energy calibration of the detector with several tens of thousands detecting elements.
A known approach for addressing issue is to obtain the K-absorption edge of a subject by positioning a subject for calibration between an X-ray tube and a detector, differentiating the energy profile of the linear attenuation coefficients of the subject, and estimating the local maximum.
With this approach in which the K-absorption edge of the subject is obtained by estimating the local maximum, however, a signal giving the local maximum in the differential waveform of linear attenuation coefficients, which is at the inflection point of the curve representing the K-absorption edge of the subject, shifts depending on the detector response. An indirect conversion detector using a scintillator, in particular, has a quite low energy resolution, that is, approximately 20 percent or so (estimated with 122 kilo-electron volts), so the detection of the exact K-absorption edge is quite difficult.
Furthermore, a cerium-doped lutetium yttrium orthosilicate (LYSO) crystal or LSO (Lu2SiO5) crystal, which includes lutetium (Lu) as a constituent element of the scintillator provided to the detector, include unstable Lu isotopes. When these unstable isotopes stabilize, three gamma rays (at 88 kilo-electron volts, 202 kilo-electron volts, and 307 kilo-electron volts) are emitted, while cascade transition takes place. An energy calibration method that measures the background radiation of Lu elements using this phenomenon is also known.
This approach, however, may require a long time and consume an enormous amount of power to calibrate, because Lu has low radioactivity. Furthermore, the calibration needs to be carried out during the time in which the device not in use, e.g., during night time. Furthermore, because radiation detecting apparatuses require energy calibration in a range from 0 kilo-electron volts to 150 kilo-electron volts, the precision of the energy calibration is reduced merely with three gamma rays.

Radiation detecting apparatus, input-output calibration method, and computer program product