Surface-modified nanoparticles of boehmite, and methods for preparing the same. Aluminum oxyhydroxide nanoparticles are surface modified by reaction with selected amounts of organic acids. In particular, the nanoparticle surface is modified by reactions with two or more different carboxylic acids, at least one of which is an organic carboxylic acid. The product is a surface modified boehmite nanoparticle that has an inorganic aluminum oxyhydroxide core, or part aluminum oxyhydroxide core and a surface-bonded organic shell. Organic carboxylic acids of this invention contain at least one carboxylic acid group and one carbon-hydrogen bond. One embodiment of this invention provides boehmite nanoparticles that have been surface modified with two or more acids one of which additional carries at least one reactive functional group. Another embodiment of this invention provides boehmite nanoparticles that have been surface modified with multiple acids one of which has molecular weight or average molecular weight greater than or equal to 500 Daltons. Yet, another embodiment of this invention provides boehmite nanoparticles that are surface modified with two or more acids one of which is hydrophobic in nature and has solubility in water of less than 15 by weight. The products of the methods of this invention have specific useful properties when used in mixture with liquids, as filler in solids, or as stand-alone entities.

Organic carboxylic acids have long been known to react with inorganic particulate minerals, including alumina and other aluminum oxyhydroxides, to produce fillers that disperse more easily than the base inorganic particulate in paints, plastics, rubbers, adhesives, caulks and other composites materials. For example, U.S. Pat. No. 4,420,341 (Ferrigno, 1983) describes surface modified fillers with improved properties that comprise a particulate mineral, an organic acid, an antioxidant, and a liquid agent. U.S. Pat. No. 4,283,316 (Bonsignore 1981) describes the modification of alumina hydrates with liquid fatty acids to make them compatible with thermoplastic polymers, and U.S. Pat. No. 4,191,670 describes the treatment of mineral fillers with a mixture of saturated and unsaturated aliphatic acids. However, the above cited patents do not specifically address the technical challenges of working with nanoparticle materials that have at least one dimension of less than 100 nm. [Also see for example "Filler surface modification with organic acids," Plastics, Additives and Compounding Volume 2, Issue 12, December 2000, Pages 26–29, Elsevier Science and "Thermochemical study of Adsorption Behavior of Polyacrylic Acid on Alumina Powder Surface" Uchida et. al., Key Engineering Materials, Vols. 161–163 (1999), p. 133–136]
Nanoparticle materials (that have at least one dimension less than 100 nm) offer unique properties not available with corresponding macro- or micro-fillers. For example, large improvements in barrier, mechanical, or thermal properties have been demonstrated in nylon-clay nanocomposites containing only a few volume percent of the clay nanofiller. With conventional fillers, volume fractions of 30%–40% are required to achieve similar improvements. Improvements in the nylon nanocomposites included a doubling of the tensile modulus and strength for clay loadings as low as 2 vol. % inorganic. In addition the heat distortion temperature of the nylon nanocomposites was increased by up to 100° C. [see for example, U.S. Pat. No. 4,739,007; Kojima et al. "Mechanical properties of nylon 6-clay hybrid", J. Mater. Res., (1993), 8, 1185–1189; Usuki, et al. "Synthesis of nylon 6-clay hybrid", J. Mater. Res., (1993), 8, 1179–1184; Yano et al. "Synthesis and properties of polyimide-clay hybrid", J. Polym. Sci. Part A, (1993), 31, 2493–2498]. Also, particulate fillers have long been known to impart desirable properties to a variety of polymeric materials. For example, mica increases the stiffness of phenol-formaldehyde plastics (A. King "Application of Fillers" in Plasticizers, Stabilizers, and Fillers, P. D. Ritchie ed, Iliffe Books, London, 1972.) Plate-like fillers have been known to improve the barrier properties of their composites (A. A. Gusev and H. R. Lusti, "Rational Design of Nanocomposites for Barrier Applications", Advanced Materials, 2001, Vol. 13(21), 1641–1643). Many other polymers and nano-fillers have been studied in addition to nylon-clay nanocomposites.
As evident from the large amount of research carried out in the field on nanomaterials and nanocomposites over the past decade [see for example: Dagani R., "Putting the "Nano" into Composites", Jun. 7, 1999, C&EN, 25–27; Thayer A. M., Nanotech offers some there, there", Nov. 26, 2001, C&EN, 13–16; and Beall, G. W., "New Conceptual Model for Interpreting Nanocomposite Behaviors" in "Polymer-Clay Nanocomposites", Pinnavaia T. J. and G. W. Beall, Eds., 2001, John Wiley & Sons, Incorporated, Chichester, England, pages 267–279], the methods and principles used for processing traditional macroscopic and microscopic fillers cannot be readily translated into nano-sized materials. Nano-sized filler materials are substantially more challenging to process than common macro- and micro-fillers because their extremely high surface area causes problems of high viscosity when mixed with liquids or polymers and problems of high oil absorption when mixed in resins and oligomers. Foaming or defoaming are other common side-effects of amphiphilic nano-fillers. Agglomeration during drying or processing is another common problem of nano-sized fillers.
In many cases, it is advantageous to provide inorganic particles with an organic surface modification. Modifying the surface of particles that are added to a polymer matrix to form a composite can improve the wetting of the particles by the matrix and improve the dispersion of the particles in the matrix, thereby improving such properties of the composites as strength, toughness, and the ability to act as a barrier. Surface modifications can also improve the adhesion between the particles and the polymer, thereby improving the load transfer and the mechanical properties of the composite. For example, U.S. Pat. No. 4,091,164 teaches the modification of kaolin clays by mixing the clay particles with block copolymers of ethylene oxide and propylene oxide and then melting the polymers so that they adhere to the clay particles. Surface modifications have also provided particulate fillers the ability to bond with a matrix, as is described in e.g. U.S. Pat. No. 3,901,845, which teaches coupling of a mineral filler with a nylon matrix by an aromatic compound having a carboxyl group and a hydroxyl or amine group. PCT application WO 00/09578 and U.S. Pat. No. 6,369,183 B1 also teach surface modification of a filler followed by coupling of the filler to an organic matrix.
Boehmite is a particularly useful material for polymer nanocomposites because agglomerates of nanosized primary particles are readily available at low cost and high purity, and the commercially available agglomerates can be processed into primary particles. The surface of the boehmite can be modified with organic molecules via bonding between carboxylic acid groups and the boehmite surface. Also, nanoparticles can be made which have a boehmite surface layer and a non-boehmite inner core. For example, alumina nanoparticles can be coated with a boehmite surface layer and then modified with organic acids.
Some of the challenges of working with nano-sized fillers have been addressed in the past. A particularly vexing problem is the tendency of nanoparticles to strongly stick together, forming agglomerates of many primary nanoparticles that can be much larger and therefore less useful than the primary particles. Even worse, even if the agglomerates are broken apart, the particles tend to phase separate and re-agglomerate when they are added to a polymer. For example, U.S. Pat. No. 5,935,275 (Burgard, Nass, Schimdt, 1999) reports methods to prepare weakly agglomerated nano-sized particles, U.S. Pat. No. 6,190,731 (Tecle, Berhan, 2001) reports methods to make isolated ultrafine particles by encapsulating a highly dispersed colloidal suspension with an encapsulant material, and U.S. Pat. No. 6,537,665 (O'Connor, Nehring, Russell, 2003) reports a particulate powder adapted for dispersion in organophilic solvents that comprises a powder particulate material, a first coating on the particulate material that contains a reagent that causes the surface of the particles to be reactive to an organic acid derivative, and a second coating that covers the first coating and contains an amphiphilic surfactant and an organic acid derivative.
More specifically, methods have been reported to prepare organic surface-modified aluminum oxyhydroxide particles of nano-sized dimensions [U.S. Pat. No. 6,369,183, Cook and Barron et al. in Chem. Mater. 1996, 8, 2331–2340, Landry, Barron et al. in J. Mater. Chem. 1995, 5(2), 331–341; Cook, Barron et al. in Chem. Mater. 1997, 9, 2418–2433, Barron et. al. in Chem. Mater. 2000, 12, 795–804, Barron et al. in Macromolecules, 2000, 12,795–804, and Obrey and Barron in Macromolecules, 2002, 35, 1499–1503.]. However, these reported methods produce materials with different (and less useful) properties than the materials prepared according to the present invention. These references have focused on the dispersion of boehmite nanoparticles for the purpose of processing them in aqueous solutions. Typically, these dispersed boehmite nanoparticle solutions are used as precursors in the production of ceramic materials. The organic acids are used primarily to disperse the nanoparticles into water and there is no need to design the nature of the organic modifying groups or use multiple acids to achieve a more specific surface chemistry so that they interact correctly when they are added to a polymer to form a nanocomposite. These references do not teach the production of surface-modified boehmite nanoparticles that have two or more organic acids. Using multiple (two or more) acids, in contrast to a single acid, yields many more possible types of surface chemistries that allow one to tailor the solubility, surface-graft density, and the length of attached organic groups, and to vary combinations of the length of attached organic groups to provide specific nanoparticle-polymer interactions. For example, one organic acid can be used to tailor the surface properties to prevent agglomeration and/or phase separation, while another can be used to attach other useful functionalities to the particle. An additional advantage of using multiple acids for surface modification is the possibility to introduce on the surface complementary functional groups such as a catalytic site and a co-catalyst. Particularly useful applications of nanoparticles functionalized with two acids have been reported in commonly owned U.S. Pat. No. 6,933,046, issued Aug. 23, 2005; U.S. Pat. No. 6,986,943; issued Jan. 17, 2006 and U.S. Pat. No. 6,887,517, issued May 3, 2005.
One useful aspect of the present invention is a method for producing surface modified nanoparticles in which some of the organic modifiers are large molecules, having a molecular weight greater than or equal to 500 Daltons. Others have described the difficulties associated with trying to attach large molecules (defined as larger than 500 Daltons) to nanoparticles [U.S. Pat. No. 5,593,781 Nass, Schmidt and Schmitt]. The present invention teaches a method for partially modifying nanoparticle surfaces with some small molecules at a concentration sufficient to provide for dispersion in appropriate solvents and subsequent addition of large molecules directly to the nanoparticle surface. Similarly it has been difficult to react hydrophilic inorganic particles such as boehmite with hydrophobic molecules that are not water-soluble. The present invention provides a means to modify boehmite particles with hydrophobic carboxylic acids.
Additionally, previous works have not taught the significance of limiting the amount of carboxylic acid used to modify the surface of boehmite so that the acid does not chemically alter the boehmite material. In the present invention the ratio of acid to boehmite is limited to prevent unwanted degradation of the boehmite. The following references and examples 1, 2 and 3 (herein) will illustrate this principle.
U.S. Pat. No. 6,224,846 (Hurlburt, Plummer, 2001) teaches a method of making a dispersible alumina by reacting a slurry of boehmite in water with the salt of an organic sulfonic acid. Sulfonic acid derivatives are highly hydrophilic and therefore are often not desirable in many coating and plastic applications. Therefore, there is an advantage in using hybrid nanoparticles that do not contain sulfonic acids. Hurlburt and Plummer do not teach the reaction of multiple sulfonic acid groups with boehmite. U.S. Pat. No. 6,224,846 also reports a process for preparing metal oxide particles modified with sulfonic acids.
U.S. Pat. No. 4,676,928 (Leach, Decker, 1987) reports a process for producing a water dispersible nano-sized alumina by forming an aqueous alumina slurry from an uncalcined alumina and admixing a monovalent acid to produce an alumina slurry-acid composition having a pH of 5.0 to 9.0, and then aging the composition at a temperature higher than 70° C. The alumina content of the slurry is reported to be 9 to 15% by weight. Monovalent acids disclosed in U.S. Pat. No. 4,676,928 include nitric acid, hydrochloric acid as well as, formic acid, and acetic acid. However, most of the examples show the use of nitric acid (an inorganic acid) with the exception of Example 11 of U.S. Pat. No. 4,676,928, where either acetic acid or formic acid is used. In this example, the alumina slurry was aged at 190° F. for a month to obtaining a water dispersible sol. Leach and Decker only teach the use of a single organic acid, and they teach that it is preferable to use nitric acid, which is not a carboxylic acid.
U.S. Pat. No. 5,593,781 (Nass, Schmidt, Schmitt, 1997) reports a method of manufacturing surface-modified nanometer size ceramic powder by suspending the powder in water or an organic solvent, adding an organic compound which interacts or reacts with groups present on the surface of the ceramic powder, then removing the water or organic solvent. The nanometer-sized ceramic powders of U.S. Pat. No. 5,593,781 include aluminum oxyhydroxides and the modifying organic groups include carboxylic acids. This patent does not teach the use of multiple carboxylic acids and does not teach or recognize the benefits of using multiple carboxylic acids.
U.S. Pat. No. 6,030,599 (Noweck, Schimanski, Meyer, 2000) reports a process for producing water-dispersible alumina hydrates by hydrolyzing and condensing an aluminum alcoholate in water in the presence of a polymerization inhibitor selected from a group of compounds that comprise organic and inorganic acids. Similarly, U.S. Pat. No. 4,211,667 (Yamada, Yoshihara, Ishida, and Sato, 1980) reports a process for producing an alumina sol by neutralizing a water-soluble aluminum salt to produce an alumina gel and then subjecting the gel to hydrothermal treatment in the presence of a single monovalent organic acid. In contrast, the present invention teaches a process that utilizes pre-formed aluminum oxyhydroxide particulate materials. Since aluminum oxyhydroxide powders that are useful for this invention are commercially available in large quantities and at reasonable price, it is advantageous in many situations to start from the pre-formed ceramic powder, rather than have to carry out the hydrolysis and condensation of aluminum alcoholates or aluminum salts as described in U.S. Pat. Nos. 6,030,599 and 4,211,667.
Apblett et al. [Mat. Res. Symp. Proc. Vol. 249 1992] reports the formation of carboxy substituted particles from the reaction of pseudoboehmite and a single carboxylic acid.
Landry et al. [J. Mater. Chem. 1995, 5(2), 331–341] describe the reaction of [Al(O)(OH)]n with a single carboxylic acid (HO2CR) to form species [Al(O)x(OH)y(O2CR)z]n where R=C1–C13 and 2x+y+z=3. No mixed species, where different R groups were substituted on the alumoxane, were reported.
U.S. Pat. No. 4,983,566 (Wieserman, Karl, Cross, Martin, 1991) reports materials comprising a metal oxide/hydroxide particle that have been reacted with a prefluorinated organic acid, including multiple perflourinated carboxylic acids. Wieserman et al. do not teach the use of organic carboxylic acids having at least one C—H bond.
U.S. Pat. No. 6,369,183 (Cook, Barron, and others, 2002) reports thermoset polymer compositions formed by reacting amine, hydroxyl, acrylic and vinyl substituted carboxylato-modified boehmite with low molecular weight polymer precursors to form a cross-linked network in which the particles are covalently linked to the polymeric matrix. This patent reports methods for preparing these substituted carboxylato-modified boehmite particles (called carboxylato-alumoxanes). However, the materials prepared according to this patent are different (i.e. have different properties) from the materials prepared according to the present invention. In Examples 2–14 of U.S. Pat. No. 6,369,183 carboxylato alumoxane are prepared by mixing boehmite with a carboxylic acid in a ratio of total aluminum atoms of the boehmite to carboxylic acid ranging from 1:4 to 3:2. The use of such high ratios of acid to boehmite attack and in some cases dissolve the boehmite particles, as will be described in more detail herein In contrast, the method of the present invention limit the amount of acid used to avoid, minimize or control the dissolution of boehmite nanoparticles. The dissolution of boehmite can be observed by the disappearance of the typical peaks of boehmite in the XR-D of the product and appearance of new peaks (as shown in Examples 2B and 3B, herein).
Examples 1A, 2A, and 3A and comparative examples 1B, 2C, and 3B, herein show the differences in properties of materials prepared according to this invention and materials prepared according to the methods of U.S. Pat. No. 6,369,183 As evident from the X-RD of the products, partial or complete dissolution of the boehmite particles occurs when high concentration of acids are used according to U.S. Pat. No. 6,369,183. Additionally, in contrast to the materials of this invention, the carboxylato alumoxanes prepared according to U.S. Pat. No. 6,369,183 B1 can be separated in two or more fractions of different chemical compositions that have different solubility properties. Furthermore, when using acids that contain polymerizable double bonds (such as methacrylic acid in Example 14 of U.S. Pat. No. 6,369,183 B1) the product contains polymerized methacrylic acid.
The synthesis of carboxylato alumoxanes from boehmite and carboxylic acids is also reported in Cook, Barron et al. Chem. Mater. 1996, 8, 2331–2340, Landry, Barron et al. J. Mater. Chem. 1995, 5(2), 331–341, Cook, Barron et al. Chem. Mater. 1997, 9, 2418–2433, Barron et. al. Chem. Mater. 2000, 12, 795–804, Barron et al. iMacromolecules, 2000, 12, 795–804], and Obrey and Barron Macromolecules, 2002, 35, 1499–1503. All the materials reported in these papers are prepared by reacting boehmite with 1–40 molar equivalents of an organic carboxylic acid. As detailed above and demonstrated by the comparative examples 1A versus 1B, 2A versus 2B and 3A versus 3B, the properties of the materials obtained with these prior art methods are different from the properties of the materials obtained according to the method of present invention.
Example 48 in U.S. Pat. No. 6,369,183 reports the production of a modified pseudoboehmite particle employing methoxyethoxyacetic acid (MEEA) and sebacic acid. The boehmite is first reacted with MEEA to form a "MEEA-alumoxane" (e.g. a boehmite particle that has been reacted with methoxyethoxyacetic acid) and then the reacted product is stirred for several hours with sebacic acid. The reference teaches making the materials using a level of acid greater than 1:1 (aluminum to acid mole ratio). It does not teach using multiple organic acid beohmite nanoparticles at a loading level (2:1 aluminum to acid or at lower acid levels) that results in the materials described in the present invention. Furthermore the product of Example 48 of U.S. Pat. No. 6,369,183 is an insoluble cross-linked material. The sebacic acid used in that example has two reactive carboxylic acid groups and therefore reacts with more than one particle forming a continuous network of cross-linked particles. In contrast, the methods of this invention produce surface-modified nanoparticles that are not cross-linked with other particles and therefore retain their ability to disperse in water, solvent, polymers, resins and other systems.
There is a need in the art for surface-modified boehmite nanoparticles that are not cross-linked or otherwise aggregated and which exhibit useful rheologic properties including dispersibility in water, water/solvent mixtures, and selected organic solvents as well as in polymers, resins and other materials. Additionally, there is a need in the art for surface-modified boehmite nanoparticles in which the density of organic groups on the surface is selectively controlled to adjust and control the surface properties of the particles.

Nanoparticles modified with multiple organic acids


Disclosed is an apparatus and method for controlling the data size of an electronic mail. A computer program executes the method as follows. A mail controlling section compresses data of an electronic mail so that the data size is not more than an unsendable size recorded in relation to a destination electronic mail address by referring to an address table. A mail sending section sends the compressed electronic mail to a recipient. In the case where an electronic mail that has been received by a mail receiving section has a data size which is larger than a sendable size, an updating section updates the sendable size. Further, in the case where an error mail with regard to an electronic mail which is smaller in data size than the unsendable size is received, the unsendable size is updated.

1. Field of the Invention
The present invention relates to a technique for controlling a data size of an electronic mail.
2. Description of the Background Art
There has been known an electronic mail software program which operates on a terminal such as personal computer. An electronic mail that a sender sent using electronic mail software is transferred to a mail server of sender side specified in the electronic mail software. The mail server sends the received electronic mail to a mail server of recipient side where a post of a destination electronic mail address exists, in accordance with the destination electronic mail address. Likewise, the recipient receives the electronic mail that has been mailed in his/her own post with the use of electronic mail software operating on a terminal such as personal computer. In this way, the electronic mail system is operated.
In the above system, an electronic mail sent by a sender is transferred by a mail server of sender side. However, since a mail server serves to process electronic mails of a number of users, it provides a limitation for a data size of electronic mail from the view of its throughput or servability.
In view of this, Japanese Patent Application Laid-Open No. 2000-29797 and Japanese Patent Application Laid-Open 2001-14235 disclose techniques in which electronic mail software downloads from a mail server of sender side information regarding a limitation of data size, and cancels sending of electronic mails of data size larger than the limitation.
Furthermore, Japanese Patent Application Laid-Open No. 11-196218(1999) discloses a technique in which an electronic mail having a data size of equal to or more than a specified data size is sent by being divided. Also, Japanese Patent Application Laid-Open No. 11-32196(1999) discloses a technique in which information of data size which is specified for every network type is possessed and a data size of a send mail is limited.
In this way, such a case that a sent electronic mail is rejected by a mail server and sent back as an error mail is avoided.
However, in the techniques disclosed in the above described Japanese Patent Application Laid-Open No. 2000-29797 and Japanese Patent Application Laid-Open No. 2001-14235, only the data size limited by the mail server of sender side is take into consideration, so that if the sent mail is having a size that exceeds a limitation of data size provided by a mail server of recipient side or a relay mail server passed by in transmission path between the mail server of sender side and the mail server of recipient side, the mail will be sent back as an error mail.
In addition, the technique disclosed in Japanese Patent Application Laid-Open No. 11-196218(1999) is premised on the fact that limitation values of data size specified for individual mail servers can be acquired, while the technique disclosed in Japanese Patent Application Laid-Open No. 11-32196(1999) is premised on that limitation values of data size specified for individual network types can be acquired. For this reason, these technique are not applicable when firm limitation values specified for individual mail servers and networks cannot be acquired, and still have a problem that an electronic mail having a relatively large data size is sent back as an error mail.

Electronic mail sending apparatus and method


A terminal control method, a terminal and a non-transitory computer-readable storage medium are provided. The terminal control method includes: receiving, by a microphone, a detection audio signal emitted from a speaker and having a frequency within a pre-set detection frequency range; acquiring actual audio parameters of the detection audio signal when being received by the microphone, and original audio parameters of the detection audio signal when being emitted from the speaker; determining a relative state between the microphone and the speaker according to the actual audio parameters and the original audio parameters; determining a terminal control operation to be performed, according to the relative state and a pre-set correspondence between relative states and terminal control operations; and performing the determined terminal control operation on a terminal where the microphone is located.

The application environment for mobile terminals is becoming more and more complex, and requirements by the industry and users on intelligent performance of the terminals are becoming higher and higher. Conventional control on a terminal is generally achieved by performing a touch operation on a touch screen when the touch screen is lit, but controlling the terminal through the touch operation is cumbersome and the control efficiency is low.

Terminal control method, terminal and non-transitory computer readable storage medium


The pesticidal composition of the invention comprises dichlorvos and chlorpyrifos. The composition is prepared by combining the components together and then subjecting the mixture to microwave radiation. The resultant composition exhibits a synergistic effect on the individual properties of the respective components which not only quickly exterminates existing pests but which also leaves a residual pesticidal protection which is not readily removed by conventional cleaning processes. The composition is particularly effective against cockroaches.

There are many domestic and commercial applications wherein areas and surfaces must be protected against infestation by insects and other pests. For example, household cupboards, wardrobes, pantries and the like must be protected against invasion by ants, cockroaches and other pests. Similarly, in commercial premises and establishments such as restaurants, cafes and the like it is essential, and often mandatory under government health regulations, that areas used for the storage of food and/or the preparation and serving of meals be kept pest free.
Of particular concern are German cockroaches. These pests have a marked resistance to most of the known pesticides, including the synthetic pyrethroids. Conventional treatments only remove this species of cockroach for a period between several days and three months. Further, conventional treatments do not affect any eggs which may have been deposited by the female cockroach. Accordingly, the eggs hatch and re-infestation occurs.
In the past, organo phosphates were the preferred choice for the extermination and control of these pests, although they have been virtually superceded today by synthetic pyrethroids and carbamates. However, two well-known organo phosphates still in use are dichlorvos and chlorpyrifos. Dichlorvos is commonly used as a fumigant and thus used when it is necessary to kill pests already present in an affected area. Chlorpyrifos is a residual and is, therefore, utilised to keep an already cleared area free from pests. It is primarily used as a surface spray for short to medium-term residual control. Commercial suppliers of chlorpyrifos estimate its effective life to be approximately three (3) months. Nevertheless, individually, neither dichlorvos nor chlorpyrifos are considered to be very effective.
It is also known to provide a pesticidal composition which is a combination of fumigant and residual ingredients. In fact, dichlorvos has been used as an additive to a residual-type pesticide. Although when used as such an additive, dichlorvos does reduce the "knockdown" time required to eliminate existing pests, it does not increase the effective life of the residual ingredient to which it has been added. For this reason, dichlorvos is rarely used now in the pest control industry as the extra expense incurred in its inclusion in the composition to reduce the immediate numbers of pests present is not outweighed by any lasting advantage of the residual component.
Further, a disadvantage of the residual chlorpyrifos is that it is readily removed by cleaning of treated surfaces, such cleaning, of course, being a regular occurrence in food storage, preparation and serving areas.
Yet another disadvantage of prior pesticidal compositions, whether they contain residual ingredients or not, is that a pest usually must remain in a treated area for a sufficient period for the pesticidal composition to be effective. If the pest remains for that sufficient period, then often enough contact with the active ingredient has been made to eradicate the pest, even if the pest first leaves the treated area before dying. On the other hand, if the pest leaves the treated area before sufficient contact is made with the active ingredient, then the pest may again return to the area as it is unaware that that environment is hostile to it.


An active damage interrogation (ADI) system (and method) which utilizes an array of piezoelectric transducers attached to or embedded within the structure for both actuation and sensing. The ADI system actively interrogates the structure through broadband excitation of the transducers. The transducer (sensor) signals are digitized and the transfer function of each actuator/sensor pair is computed. The ADI system compares the computed transfer function magnitude and phase spectrum for each actuator/sensor pair to a baseline transfer function for that actuator/sensor pair which is computed by averaging several sets of data obtained with the structure in an undamaged state. The difference between the current transfer function and the baseline transfer function for each actuator/sensor pair is normalized by the standard deviation associated with that baseline transfer function. The transfer function deviation for each actuator/sensor pair is then represented in terms of the number of standard deviations, or sigmas, from the baseline. This statistic, termed the TF Delta, is then processed by a windowed local averaging function in order to reduce minor variations due to random noise, etc. The Windowed TF Delta for each actuator/sensor pair is then integrated over the entire excitation frequency spectrum, to thereby produce the Cumulative Average Delta, which provides a single metric for assessing the magnitude of change (deviation from baseline) of that particular actuator/sensor transfer function. The Cumulative Average Delta (CAD) for each actuator/sensor transfer function provides key, first-level information which is required for detecting, localizing, and quantitatively assessing damage to the structure.

The present invention relates generally to structural health monitoring methods and systems, and more particularly, to a structural health monitoring technique which actively interrogates the structure through broadband excitation of an array of piezoelectric transducers attached to or embedded within the structure for both actuation and sensing. Statistical analysis of the changes in transfer functions between actuator/sensor pairs is used to detect, localize, and assess the severity of damage in the structure.
A significant area of ongoing research and development efforts in the aerospace industry is the implementation of an automated structural health monitoring system (SHMS) using smart sensors and actuators integrated into the structure of an aerospace vehicle in order to provide a "built-in-test" (BIT) diagnostic capability for the structure. Such "smart structures" facilitate a reduction of acquisition and life cycle costs of aerospace vehicles which incorporate the same. A reliable SHMS will enable the practice of condition-based maintenance (CBM), which can significantly reduce life cycle costs by eliminating unnecessary inspections, minimizing inspection time and effort, and extending the useful life of new and aging aerospace structural components.
A principal requirement of an integrated SHMS is to provide a first level, qualitative damage detection, localization, and assessment capability which can signal the presence of structural damage and roughly localize the area where more precise quantitative non-destructive evaluation of the structure is needed.
Previous SHMS devices have primarily relied upon "passive" strain tracking or acoustic emission monitoring techniques, both of which have serious drawbacks and shortcomings. More particularly, both of these structural health monitoring techniques require continuous monitoring of the structure under evaluation in order to detect any damage to the structure. Thus, if a power failure (or power shut-down) occurs, the SHMS device is disabled. Further, the accuracy and reliability of the acoustic emission monitoring technique is compromised by the generally noisy environment of the aerospace vehicle. Another major disadvantage of acoustic emission (AE) monitoring is that a significant amount of data storage is required. The strain tracking technique requires the costly development of a finite element strain distribution model against which to compare the measured strain distribution across the structure in order to quantify and localize the damage. Moreover, both of these structural health monitoring techniques are severely limited with respect to their sensitivity, i.e., their ability to detect structural damage at the smallest possible level.
The most promising structural health monitoring techniques currently under development involve the use of piezoelectric transducers to actively excite and sense the vibration characteristics of the structure. This vibration signature is then compared with that of a normal undamaged structure and the difference is used to extract a metric related to the health of the structure. These structural health monitoring techniques can thus be regarded as "active" vibration-based structural health monitoring techniques.
Chaudhry et al. have demonstrated the use of piezoelectric transducers for local-area damage detection in metallic structure bond lines and joints, as well as in composite repair patches for metallic structures. See, Z. Chaudhry, T. Joseph, F. Sun, and C. Rogers, "Local-area health monitoring of aircraft via piezoelectric actuator/sensor patches,", Proceedings, SPIE Symposium on Smart Structures and Materials, Vol. 2443, pp. 38-49, 1995; and, Z. Chaudhry, F. Lalande, A. Ganino, and C. Rogers, "Monitoring the integrity of composite patch structural repair via piezoelectric actuators/sensors", Proceedings, 36th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, pp. 2243-2248, 1995, the disclosures of which are incorporated herein by reference. Their technique utilizes a single piezoelectric transducer made of Lead Zirconate Titanate (PZT) bonded to the structure to obtain electrical impedance measurements across a specific frequency range using simultaneous actuation and sensing. Since the PZT provides a coupling between mechanical impedance and electrical impedance, vital mechanical impedance information of the structure can be extracted from the electrical impedance measurements. Damage to the structure affects the vibration signature of the structure. Thus, damage can be detected by monitoring the appropriate frequency spectrum of the electrical impedance function. Chaudhry et al. have demonstrated that de-bonds as small as 1/4" in the composite patch produce a noticeable change in the impedance function at frequencies between 10 kHz and 20 kHz.
Castanien and Liang have extended this technique to include the cross-electromechanical impedance between pairs of PZT transducers to aid in monitoring a larger area of the structure while still providing some localization capability. See, K. E. Castanien and C. Liang, "Application of active structural health monitoring technique to aircraft fuselage structures", Proceedings, SPIE Symposium on Smart Structures and Materials, Vol. 2721, pp. 38-49, 1996, the disclosure of which is incorporated herein by reference. They have used this technique to demonstrate detection and localization of rivet line failures in a section of metallic aircraft fuselage using a frequency spectrum of 0 to 2 kHz.
Another "active" vibration-based structural health monitoring technique is disclosed in U.S. Pat. No. 5,327,358. However, the technique disclosed in this patent requires a model of the structure under evaluation, and thus, requires a priori information about the structure (including structural material and geometric properties) for deriving the model parameters.
Although the above-described vibration-based "active" structural health monitoring techniques are promising, they do not provide any mechanism for processing the information they obtain in order to facilitate accurate quantitative assessment and localization of any detected damage to the structure under evaluation. Further, their detection sensitivity and localization capabilities are limited, e.g., with respect to composite structure delamination damage.
Based on the above and foregoing, it can be appreciated that there presently exists a need in the art for a model-independent structural health monitoring system and method which overcomes the above-described drawbacks and shortcomings of the presently available technology. The present invention fulfills this need in the art.

Active damage interrogation method for structural health monitoring


The present invention relates to an automatic power conservation method for an optical media device, which is capable of turning off other circuit components that are still in operation using the host interface of the optical media device when the optical media device enters the sleep-mode, and the host interface also being used to respond to an external signal of the optical media device; using the host interface to wake up those circuit components if the external input signal of the optical media device requesting the optical media device to exit the sleep-mode.

1. Field of the Invention
The present invention relates to an automatic power conservation method for an optical media device, and more particularly, to an automatic power conservation method for an optical media device that is capable of turning off more circuit components while operating in a sleep-mode.
2. Description of the Prior Art
Energy conservation is a common issue that is being discussed in this era which energy is consumed rapidly. Energy conservation is also an important task while designing an optical media such as CD-ROM, CD-R/RW, DVD-ROM, DVD-R, and DVD-Dual, etc. It is most desirable if the unneeded circuit components of an optical media can all be turned off while it enters the sleep-mode, which it is the main object of the present invention.
Typically, an optical media will enter the sleep-mode after idling for a period of time. The motor inside the optical media will be stopped to reduce the noise and the heat, and a portion of the circuit components on the circuit board will be turned off as well. However, when entering the sleep-mode, some of the components on the circuit board are still functioning, which include the host inference (HI) of the integrated circuit (IC), Random Access Memory Arbiter (RAM Arbiter), Micro-Computing Unit (MCU), and Dynamic RAM (DRAM).
Please refer to FIG. 1, which is a block diagram of the circuitry between the PC and the IC of a conventional optical media device. As the optical media device enters the sleep-mode, the PC, or the Host 150 will send some signals to the HI 120 of the IC 100 in the optical media. Based on the signal received by the HI 120 from the Host 150, the MCU 110 of the IC 100 will send the information of the current operating mode of the optical media device to the Host 150 through the HI 120 in response.
The optical media device can leave the sleep-mode by a request from the user through the Host 150, or through the panel of the optical media (which is not shown in the figure). However, the user wakes the optical media device up from the sleep-mode either through the Host 150 or the panel, the control signal needs to be sent from the HI 120 to the MCU 110 so that the MCU 110 can ask the optical media device to leave the sleep-mode. Moreover, while processing these signals, the MCU 110 needs to access the DRAM 140 outside the IC 100 through the RAM Arbiter 130.
Therefore, while the foregoing conventional mechanism for optical media device is in the sleep-mode, the HI 120, the MCU 110, the RAM Arbiter 130, and the DRAM 140 of the optical media device are, instead of in the sleep-mode, still processing. If these circuit components can as well enter the sleep-mode as the optical media entering the same, the power can be conserved.
In view of this, the present invention provides an automatic power conservation method for optical media device to conserve more power by turning off more circuit components when the optical media device enters the sleep-mode.

Automatic power conservation method for an optical media device


Disclosed is a method of paging an electronic device when the electronic device is in an idle state, the method comprising: determining a time; determining a primary tracking area that is associated with a time period in a profile of the electronic device, wherein the time period comprises the determined time; and transmitting a paging message to the electronic device in one or more target tracking area, the one or more target tracking area comprising the primary tracking area.

Paging can be used to communicate with an electronic device when the network (or a network component) is not aware of the location of the electronic device, such as when the electronic device is in an idle state. Paging is commonly performed by broadcasting a paging message to a number of locations. The electronic devices in each location may be configured to assess all incoming paging message. Each such message can use up battery resources on each electronic device as well as network paging channel bandwidth.
Like reference numerals are used in the drawings to denote like elements and components.


The present invention is provides towards a method and system for facilitating roaming tests for an operator in a telecommunication network. The method includes detecting a location update message of a subscriber to an HLR while switching from a first MSG/VLR to a second MSG/VLR, The method further includes holding by a value added module, a cancel location message being sent from the HLR to the first MSG/VLR. The method further includes conducting the roaming tests by the value added module, using the subscriber's profile data obtained from the first MSG/VLR. Further in the method the value added module releases the cancel location message to the first MSC/VLR.

As telecommunication technology has progressed, though on one hand it has proved immensely beneficial for all, on other hand it has given rise to various types of frauds being done in these telecommunication networks. One such fraud is called termination bypass fraud where fraudsters change the termination leg of a call (mobile call or landline call) to avoid paying termination charge to a terminating operator for this terminated call. These calls can be international or national calls that are terminated at the terminating operator. As a result of this, operators need to conduct various roaming tests to identify such frauds in the telecommunication network.
In one of the previous patents from inventors of a referenced application, a solution has been provided for developing a "A single operator and network side solution for inbound and outbound roaming tests and discoveries of roaming partner services and frauds without involving remote probes or real roamer traffic". This solution is hereinafter, referred to as "Predictive Intelligence" or "PI".
The limitation of call generation based bypass detection methods today is that because they involve only test calls with test numbers, smart bypass fraudsters can examine the patterns of these test numbers and decide to blacklist them for future bypasses. Some of the patterns on these test numbers are either they are called too many times or they are not answered many times etc. As a result, the call generation methods lose their effectiveness in bypass detection. Even though more test numbers can be introduced, the same issue of getting detected by the bypass fraudster will rise again. Besides the fact that the test numbers are limited and each time they are used, it involves more work from the operators of these numbers, thereby creating a non-scalable solution.
Another previous patent from the inventors of this patent, titled "Advanced PI" was able to overcome the limitation of call generation based bypass detection method, by applying bypass detection in a stealth manner, thus making it difficult for fraudsters to detect that they are being tested. The Advanced PI patent was creating dummy subscribers, through signaling, as roaming agents to conduct these roaming tests. As the roaming agents were dummy subscribers there was no formal location area stored in MSC/VLR. In order to conduct these tests a virtual subscriber had to be created in the HLR, and for that a fake MT call was made to the VLR. As a standard process, the HLR would issue a PRN to the VLR to get MSRN of the subscriber. Now since the VLR does not have subscriber profile, it would issue a Restore Subscriber Data (RSD) message to HLR to get profile of the virtual subscriber restored. Since the subscriber's location info is not stored in VLR, some operators may want to avoid searching their complete network for the missing subscribers and may not return any MSRN.
Even when the operators page a location area to know the subscriber location, then the MSC has to page all location areas using Search MS message. This requires a lot of paging. In some cases, many MSC /VLRs may be shared/pooled, and the whole country may even share the same MSC. In such situation, in order to locate the subscriber, entire country would have to be paged, which is unrealistic. In some cases, it has also been observed, where PRN results in "system failure", but RSD happens, therefore validity of the VLR, profile download, SMS etc. can be evaluated, not receiving any MSRN limits the missing control on voice calls.
It has been also observed during PI and Advanced PI deployments that large number of MSC/VLRs deviate from the "VLR restoration" standard. As a result of which, the VLRs do not allow MAP RSD. Statistically, more than 40% of VLRs today do not allow creation of virtual subscribers. Assuming that worldwide we have 2000 VLRs, then only 60% of them can be tested.
The PI deployment in general relies on Restoration Procedure standard. The procedure for restoring a subscriber profile is defined in the ETSI TS123.007 document. The procedure is complete—i.e. actually restore the subscriber profile using the RSD message—for a VLR: If the indicator "Subscriber Data Confirmed by HLR" is "Not Confirmed" the VLR requests authentication data, if required and still not available and subscriber data from the HLR.
However, the same procedure doesn't exist for SGSN—i.e. the RSD procedure does not exist for SGSN. In other words, while MT calls triggers a profile restoration from the HLR, there is no MT activity at SGSN having the same effect:                For the MT SMS: It rejects the SMS request and returns a failure report with cause value "Unidentified Subscriber" to the SMS gateway MSC indicating unsuccessful delivery of the SMS        For the MT user data session: When the SGSN receives a tunnel PDU for which no PDP context exists it discards the tunnel PDU and sends an Error indication message to the originating GGSN        For MT Paging via MSC/VLR (Gs interface): If the "SGSN-Reset" indicator is set to "false" and the IMSI is unknown or the MS is marked as GPRS or non-GPRS detached by the SGSN, the paging request is rejected.
All these situations weaken the overall business case for using Advanced PI. In accordance with the foregoing, there is a need in the art of a system and a method for allowing an operator to conduct roaming tests using necessary intelligence to deal with above-mentioned problems.

Value added module in predictive intelligence


Preferred embodiments include associating surface material samples with a business entity within one or more computer databases wherein at least one of the surface material samples are labeled with information specified by the business entity. Data requests are received for at least one of the surface material samples and include an identifier of the business entity. A response to the data request includes at least one of the surface material samples and associated label information. The response to the data request may be layered based upon supply chain layer.

1. Field of the Invention
The present invention relates to data processing including business practice and management (US Class 705).
2. Background Art
In many commercial industries today, manufacturers, distributors and retailers rely on custom-labeled merchandise to market a manufacturer's product under different brands that are unique to each participant in the supply chain. This methodology enables supply chain participants to leverage their goodwill and sell more products.
Prior art methodologies for custom-labeling goods include manually branding physical items with specific printing, text or other labeling that is unique to a particular manufacturer, distributor or retailer within a supply chain. What is needed is an automated methodology and system for custom-labeling content (e.g., goods, samples, media, etc.).

Method and system for presenting custom-labeled surface material samples over a computer network


A clock delay circuit which creates control signals relative to a clock signal which vary in relation to inherent variables arising from manufacturing process, temperature and voltage influences on a memory array. The clock delay circuit preferably comprises a pair of spare word lines and a pair of spare bit lines of the memory, each of which extends across the memory array. Signals conducted along the spare word and bit line create a signal which is supplied to a counter and decoder to supply a plurality of control signals having a timing relationship established relative to the clock. The spare word line and spare bit line comprise electrical characteristics affecting signal propagation time similar to a signal propagation time along one of an actual word line or actual bit line, respectively.

A DRAM is a memory element which typically holds and supplies information in a microprocessor based computer system. The microprocessor based system may be a general purpose computer system or may be an application-specific integrated circuit (ASIC) or a system-level integrated circuit (SLIC) which is fabricated to perform a specific function. The system uses a system clock which provides pulses at a predetermined rate. The system clock pulses coordinate many system functions and operations, including generally synchronizing the timing of the DRAM operations with those of the microprocessor. The DRAM delivers information to, and receives information from the microprocessor, via electrical conductors over a system bus. The information stored in the DRAM is used by the microprocessor for computation and control of other peripheral components typically associated with the microprocessor-based system.
The typical DRAM comprises a plurality of DRAM segments and control logic for controlling the DRAM segments. The typical DRAM segment is formed by thousands of individual memory cells arranged in a matrix-like configuration. Each DRAM cell includes a capacitor which is electrically charged in a "write" operation. The electrical charge establishes a voltage on the capacitor, and the level of the voltage represents data. A higher voltage level represents a "1" data bit, while a lower voltage level represents a "0" data bit, or vice versa. The voltage level on the capacitor is sensed during a "read" operation.
The cells of the matrix are addressed by signals supplied on a word line and signals read from selected bit lines or written on selected bit lines. The word lines extend along horizontal rows of cells and intersect vertical columns of cells in the matrix. The bit lines extend along vertical columns of cells and intersect horizontal rows of cells in the matrix. In concept, by energizing a selected word line and reading or writing only on selected bit lines, individual cells at the intersections of the selected word and bit lines are written or read. In this manner, unique memory "addresses" represent specific word line and bit line combinations which access the information located at the cells identified by the address. Memory cell addresses are used by the microprocessor in organizing memory information.
The control logic interacts with the microprocessor and effectively performs the read and write operations on the DRAM memory cells. The control logic receives control signals from the microprocessor requesting a read or write operation, and address signals indicating the memory cell addresses where the read or write operation is to be performed. The control logic then produces the necessary control and address signals to carry out the read or write operation on the addressed memory cells. For a write operation, the microprocessor also provides the data to be stored in the addressed memory cells. For a read operation the data obtained from the addressed DRAM cells is supplied to the microprocessor.
In order for the DRAM control logic to use the information supplied by the microprocessor, which may only be available for a short period of time, the control logic temporarily stores the information in temporary "input" registers. The DRAM control logic recognizes when the information is available and produces a "latch control signal" that secures or "latches" the information into the temporary registers. Thus, the latch control signal produced by the DRAM control logic stores the information located on the address and data buses into the temporary DRAM registers.
Ideally, the DRAM control logic should latch the information into the temporary registers with the same system clock pulse used by the microprocessor to place the data and address information on the system bus. However, the signals on the system bus must propagate through the microprocessor logic and along the system bus until they appear at the DRAM. Because of signal propagation effects, the information on the bus usually is not stabilized until after the system clock pulse has passed. Therefore the DRAM control logic cannot use the same system clock pulse and must create a delayed latch control signal to store or latch the information into the registers once the information has stabilized.
Consequently, the DRAM control logic must generate a number of DRAM control signals internally, independently of the system clock but not synchronized with the system clock pulses. However the DRAM control signals must occur within predetermined time limits set by the system clock, in order to interface and coordinate with the system operation in a time-efficient manner. The timing characteristics of the DRAM control signals are dependent on the characteristics of the DRAM which may vary from one DRAM to another or may vary according to the different types of SLICs into which the DRAM is integrated.
Delay circuits are typically used in the DRAM control logic to create the latch control signal. Otherwise, the DRAM control logic would be forced to use the next system clock pulse as a control signal to store the microprocessor-created information into the temporary registers. Waiting for another system clock pulse significantly slows the speed of the memory, slows the performance of the system microprocessor, and is thus undesirable.
After storing the information in the temporary registers using the DRAM latch control signal, the DRAM control logic uses the stored information to read or write the memory cells during the next system clock cycle. To read memory cells, a segment enable control signal is delivered to a segment of the DRAM array containing the particular cells. Additionally, address signals indicating the particular word and bit lines to be activated are also delivered to the DRAM segment. The energized word line signal causes a transistor in the memory cells of that row to become conductive. With the transistors in a conductive state, the voltages existing on the memory cell capacitors are placed on the bit lines associated with that DRAM segment. Control signals are conducted to enable sense amps of the selected bit lines and sense the voltage on the bit line connected to the particular memory cell and complete the read process.
The sense amps compare a bit line voltage to a threshold voltage and determine whether the bit line voltage is higher or lower than the threshold voltage. If the voltage is higher than the threshold voltage, then the information stored in the memory cell represents a 1 data bit. Similarly, if the voltage is lower than the threshold voltage then the information stored in the memory cell represents a 0 data bit. The opposite relationship may also be employed to establish 1 data bits and 0 data bits. Alternatively, two capacitors may be used to store relatively different charges to represent the data bits. Instead of comparing the charge of one capacitor to a threshold voltage, the two stored charges are compared to each other. Comparing the relative voltage relationship yields the 1 and 0 data bit information stored in the memory cell. The two differential capacitor DRAM memory cell structure is discussed more completely in co-pending application titled "Embedded DRAM with Noise-Protected Differential Capacitor Memory Cells," Ser. No. 09/052,279, which was filed on Mar. 30, 1998.
Generally, to accomplish sensing, the DRAM control logic delivers a sense amp enable control signal to the sense amps which persists while the sense amps are operative. The DRAM control logic negates the sense amp enable control signal when no sensing is required.
Once the sense amps have produced data bit signals based on the memory cell signals, the data is stored in a temporary "output" register in the DRAM control logic until the microprocessor is ready to accept the data, usually in the next system clock cycle after the data is available. The DRAM control logic produces a latch control signal to store the data in the temporary "output" registers in a similar manner to the creation of the latch control signal to store incoming data in the "input" temporary registers.
Additionally, the DRAM control logic produces an output enable control signal to enable the delivery of the signals from the output registers. The output enable control signal is conducted to the microprocessor after the signals from the output registers have been placed on the system data bus. Once the microprocessor receives the output enable signal, it recognizes that the data is present on the system data bus and is available to be used by the microprocessor.
Besides the control signals for the read and write operations, the DRAM control logic also produces control signals to perform other typical DRAM operations, e.g., "memory segment enable," "precharge" and "refresh." The memory segment enable operation involves the conduction of a control signal to the proper memory segment to activate that segment for either a read or write operation.
The precharge operation typically occurs before any voltages from the memory cells are applied to the bit lines. During the precharge operation, a voltage is applied to all the bit lines to charge each bit line to a point approximately midway between an expected high voltage and an expected low voltage from the memory cell capacitors. During a subsequent read or write operation, the charge on the capacitor modifies the charge on the bit line. Since the bit line has been partially charged to the midpoint between the high and low values, the time it takes for the connected memory cell capacitor to bring the bit line charge to the level of the memory cell capacitor is reduced, thus increasing the performance of the DRAM. Moreover, the time it takes to modify the charge on the precharged bit line is substantially less than the worst-case time for charging a non-precharged bit line to a high voltage level. Therefore, during a read operation the sense amps can effectively begin sensing the bit lines sooner, and during a write operation, the time allotted to charging the memory cell capacitor is reduced. Additionally, since the precharge operation can take place simultaneously with other internal operations, for example during decoding of the memory address, the overall read or write operation time is reduced.
The control logic also produces refresh control signals to refresh the charge on the memory cell capacitors since the charges are not "permanent" and dissipate after a relatively short period of time, typically on the order of a few milliseconds. Thus the DRAM control logic conducts a refresh operation which recharges the memory cell capacitors and maintains the integrity of the stored information. The refresh process typically involves reading the information stored in the memory cells, temporarily storing the information in registers, and then writing the information back into the memory cells. Read operations are destructive because they diminish the stored charge on the memory cell and for this reason, a "write-back" operation is typically performed to recharge the read memory cell. The DRAM control logic continuously refreshes the memory by performing read-write back operations on different portions of memory, before the charges have dissipated and data is lost on any portion. No data signals are required to perform the read-write back operations, since the data signals read are the same ones written back, so the DRAM control logic can perform the refresh operation autonomously. The DRAM control logic is programmed to refresh separate portions of memory during each system clock cycle. The order in which memory cells are refreshed is not overly important, as long as each memory cell is refreshed before the memory cell charge has decreased below necessary threshold levels and the data is lost. Typical DRAM memory cells require refreshing every one or two milliseconds, and the DRAM control logic assures that all the memory cells in the segment are refreshed within this time frame.
The control signals delivered by the DRAM logic are usually voltage pulses or "strobes," which remain asserted for the duration of the operation. When a control signal strobe decreases to a relatively lower level, the operation initiated by the control signal terminates. Other DRAM logic control signals may be active at a low voltage level, and a high voltage is consequently present during periods of non-operation. In either case, it is important that the strobes remain asserted until the operation has had sufficient time to complete its task, otherwise improper data storage or recovery or unreliable operation of the DRAM may result.
During the precharge operation, for example, the predetermined time period must be sufficiently long to allow all the bit lines to completely precharge to the midpoint level. The typical minimum or shortest time period for a precharge operation is defined by the time it takes for a signal to propagate along the length of a bit line with the greatest propagation time. Usually, the bit line with the highest resistence or greatest length or both has the greatest propagation time, and it determines the minimum precharge time period for a given memory segment. The DRAM control Logic should assert the precharge control signal for a time period which is equal to the minimum precharge time period. Otherwise, the DRAM control logic may assert the precharge control signal for a time period which is too short, causing premature termination of the precharge operation and resulting in inadequately precharged bit lines. Alternatively, the DRAM control logic may assert the precharge control signal for a time period which is too long and therefore waste time which might be used to perform other memory functions, thereby diminishing the performance of the memory.
The minimum time periods associated with satisfactory completion of the read, write and refresh operations are also dependent upon the time it takes for signals to propagate along the word and bit lines. The speed of the memory can be enhanced by consuming no more than the minimum signal propagation time for the read, write and refresh operations. The actual signal propagation times for each bit and word line depend on the characteristics of the bit or word line conductors, and these characteristics vary somewhat in different chips based on the manufacturing process.
The complex manufacturing process typically causes unforseen and usually uncontrollable slight variations from chips in different manufacturing lots, often resulting in propagation time variations.
Additionally, the minimum operating temperature of the chip also influences the time required to complete the DRAM operations. Typically, the operating temperature of the bit and word line conductors fluctuates during operation because of current conduction and other environmental conditions. As the temperature increases in the semi-conductors, the resistance increases and the current conduction generally decreases. As current conduction changes, signal propagation times also change. Thus, for a given voltage, operating temperatures influence the minimum time required for satisfactory completion of each operation and the optimal propagation times.
Similarly, the operating voltages applied to the word and bit lines may vary during the operation of the DRAM module and these fluctuations also affect the required minimum time periods for each DRAM operation. The primary cause of the voltage variations is due to component variations in the power supply. When the voltages applied to the bit or word lines increase, current conduction generally increases which causes signal propagation time to decrease. However, when the applied voltage decreases, the current conduction also decreases which slows signal propagation and increases the minimum time periods for each operation.
The typical approach to accounting for these process, temperature and voltage variations is to assert the DRAM control signals for time periods sufficient to accommodate worst case conditions. However, worst case timing is usually longer than necessary, and time is wasted during normal operations in accounting for worst case occasions. The performance or speed of the DRAM is slowed, or the system performance is reduced because more system clock cycles will be required to accomplish the DRAM operations.
A partial solution to these worst case variables involves a determination of the propagation times. A redundant word line is inserted in the DRAM segment, and a signal is propagated through the redundant word line at the beginning of a given memory operation. The propagation of the signal is timed by the DRAM control logic, and the additional time required for propagation is added to the minimum time periods for each operation. Once accounted for in this manner, the control signals remain asserted for a time period based on a best-case minimum time period combined with the calculated delay.
Although the additional redundant word line provides some compensation for variations in propagation times, the compensation calculation itself requires additional time and although better than worst case conditions, still may not be optimum. Furthermore, the redundant word line compensation technique will not quickly provide control timing information for all the control signals supplied by the DRAM control logic.
It is with respect to these and other considerations relating to creating DRAM logic circuits that the present invention has evolved.

Inherently compensated clocking circuit for dynamic random access memory


A device for delivery of material or stimulus to targets within a body to produce a desired response, the targets being at least one of cells of interest, cell organelles of interest and cell nuclei of interest. The device includes a number of projections for penetrating a body surface, with the number of projections being selected to produce a desired response, and the number being at least 500. A spacing between projections is also at least partially determined based on an arrangement of the targets within the body.

The present invention relates to a device for delivery of material or stimulus to targets within a body to produce a desired response, and in particular to a device including a number of projections for penetrating a body surface. The invention can also relate to devices for delivering bioactive substances and other stimuli to living cells, to methods of manufacture of the device and to various uses of the device.


In order not to have to rinse, during breaks in production, oscillating mixheads such as are used for the manufacture of free-flowing, plastic-forming reaction mixtures, an exchangeable insert part held in position by means of a clip and preferably consisting of plastic material is provided in the mixhead. The insert has a mixing chamber and an outlet channel. This insert part can be disposable or reusable.

The present invention relates to a mixhead for mixing at least two plastic-forming, free-flowing reaction components. The mixhead broadly consists of a housing with feed lines and a bore passing through the housing, in which bore an insert containing a mixing chamber and an outlet channel and inlet openings is arranged exchangeably, as known from U.S. Pat. No. 3,263,928, but without ejector piston.
The so-called double conveyor belt installations for manufacturing sandwich elements with a hard foam core, and, occasionally, continuously operating block foaming installations, are equipped with mixheads which oscillate over the foam breadth and which at the same time apply a reaction mixture to a travelling substrate. Such oscillating mixheads must be as light as possible, because considerable delay and acceleration forces occur at the turning points. The larger the mass to be moved, the greater the wear on the oscillator. Such light mixheads must be rinsed, which is generally carried out with the polyol components in the manufacture of polyurethane foam for example. But this places a burden on the environment, and uses up polyol, which also has to be disposed of due to the contamination it causes. It would be preferable t use self-cleaning mixheads (U.S. Pat. No. 3,263,928, DE-A1-2,920,388, DE-A1-3,017,950), i.e. ones with ejector pistons, such as those which have been accepted in practice for foaming in situ. But these are substantially heavier and therefore not under consideration due to the increased wear they place on the oscillator.
The object of the present invention was to find a mixhead for the application indicated, which is on the one hand light, in order to keep the mass to be moved and hence the amount of wear to a minimum, and which on the other hand does not have to be rinsed when production is interrupted.

Mixhead for mixing at least two free-flowing reaction components


A pulse-width modulation circuit converts an input signal into a pulse signal to be supplied to a switch amplifying circuit. The modulation circuit includes a comparison signal generator, an amplitude controller for modulating a comparison signal from the signal generator, and a comparator for comparing the modulated comparison signal and the input signal. The comparator outputs a signal whose level is inverted in accordance with the level of the input signal. The signal outputted from the comparator is supplied to the switch amplifying circuit.

1. Field of the Invention
The present invention relates to a pulse-width modulation (PWM) circuit and a switching amplifier using the PWM circuit.
2. Description of the Related Art
A conventional switching amplifier (e.g. an audio amplifier) is disclosed in JP-A-2003-179445, for example. The amplifier includes a pulse-width modulation circuit (PWM circuit) and a power amplifying circuit. The PWM circuit performs pulse-width modulation on inputted signals and outputs modulated signals to the power amplifying circuit, provided with a plurality of switches.
In such a switching amplifier, PWM signals are supplied to the power amplifying circuit from the PWM circuit for the purposes of controlling the voltage applied across the load (e.g. a loudspeaker). In the switching amplifier, the duration of the power voltage application to the load is varied. In this manner, the voltage applied to the load is virtually variable.
FIG. 20 is a block diagram showing a switching amplifier incorporating a conventional PWM circuit. According to this switching amplifier, as the user is adjusting the volume by operating the volume control knob (not shown) associated with a variable resistor 40, the amplitude of an audio signal (i.e. an input signal outputted from the audio signal source AU) is varied. Then, the audio signal is inputted to a PWM circuit 41, where the signal is modulated to a pulse signal having different time-widths corresponding to the amplitudes.
The output from the PWM circuit 41 is inputted to a power amplifying circuit 42. The power amplifying circuit 42 converts the input signal to a pulse signal having different levels of power source voltage corresponding to the level of amplitude. Then, the signal goes through a low pass filter LPF to remove high-frequency components, and the signal is outputted to the load L (e.g. a loudspeaker).
In the above switching amplifier, the amplitude of the audio signal is varied by the variable resistor 40, which is connected to the audio signal source AU. However, this method may suffer the following problem. Specifically, because the variable resistor 40 varies the audio signal amplitude directly, input impedance as viewed toward the audio signal source AU (signal source impedance) is also varied. The variation of the audio signal amplitude affects switching amplifier gain characteristics and S/N ratio. For example, while the noise level remains unchanged, the audio signal level is decreased. Unfavorably, this leads to a poor S/N ratio.

Pulse-width modulation circuit and switching amplifier using the same


A method for recovering platinum group metals from a catalytic structure, such as a fuel cell membrane electrode assembly, involving dissolution of the platinum group metal by treating the catalytic structure in an electrolytic cell with a suitable electrolyte containing a complexing agent and introducing an electric current into the electrolytic cell; and subsequently re-precipitating the platinum group metal by increasing the pH of the electrolyte system and adding a reducing agent.

Noble metals such as the platinum group metals are in general use as catalysts for automotive exhaust gas purification, organic chemical reactions, as well as fuel cell electrodes. They are also constituents of electronic parts. The recovery of noble metals from used materials is important due to their rarity and expense.
This has hitherto been by the dissolution process. In this process, the metals are dissolved with the carriers in hot concentrated sulfuric acid or an oxidizing acid mixture such as aqua regia, and the metals are separated from the solution by addition of a reducing agent or by electrolyzing the solution in low current density electrolytic cell. In the former case, the noble metals separate out in the solution, while in the latter case they are deposited on the cathode.
The dissolution process requires a hazardous, highly oxidizing acid that is difficult to handle, and a large amount of heat to maintain the acid temperature. Additionally, aqua regia, long been used for noble metals dissolution, gives off NOx producing pollution treatment problems. Cyanides, such as sodium cyanide, are effective for noble metals dissolution, but need careful handling and adequate liquid waste treatment due to their high toxicity.
In addition, the dissolution process is uneconomical in noble metals recovery from noble metal catalysts, because it involves the treatment of a large amount of carrier containing solutions as well as noble metals. (Noble metal catalysts are composed of carriers such as carbon, silica and alumina and very small amounts of noble metals therein. Moreover, at times a portion of noble metal is present as oxides, barely soluble in aqua regia. In such cases, it is necessary to reduce the noble metal oxides before dissolution, or perform the dissolution process in two steps, i.e., noble metal dissolution in acid and noble metal oxide dissolution in alkali.
Fuel Cells are devices that release electrical energy using an electrochemical reaction. A major class of fuel cells utilizes hydrogen fuel, and the electrochemical oxidation of hydrogen as well as the electrochemical reduction of oxygen to water is catalyzed using electrodes containing precious metal catalysts. Precious metal catalytic elements for use in precious metal catalysts include, but are not limited to, platinum (Pt), ruthenium (Ru), palladium (Pd), gold (Au), and rhodium (Rh). It is widely accepted that the high cost and limited supply of platinum and other catalytic elements are obstacles to large scale commercialization of fuel cells.
There are several types of fuel cells. Most common is the polymer electrolyte membrane (PEM) fuel cell. The PEM forms the basis for a membrane electrode assembly (MEA), which is the structure by which hydrogen can be oxidized to generate electricity. An anode (i.e., a negative electrode) is provided on one side of the PEM and a cathode (i.e., a positive electrode) is provided on the opposite side of the PEM. The anode contains a catalyst, typically comprising platinum, for promoting dissociation of hydrogen into electrons and positive hydrogen ions. The cathode also contains a catalyst, typically comprising platinum, for promoting reduction of oxygen. An MEA typically carries a catalytic element loading in the order of a few mg/cm2. Typically, these loadings in current commercial fuel cells translate to about 0.5% to 2.0% by weight of catalytic element in the MEA.
A commonly used polymer electrode membrane is Nafion™ by E.I. DuPont de Nemours Company. Nafion™, a Teflon™-based polymer, is a sulfonated perfluropolymer. Even when using a membrane that is itself free of fluorine, a perfluropolymer ionomer is typically mixed into the electrocatalyst layers (i.e., the anode and the cathode) to improve the mobility of the positive hydrogen ions. Additionally, the presence of the perfluorinated polymer makes the powder of the MEA hydrophobic when the MEA is ground.
In one type of fuel cell, the anode and cathode are coated onto the PEM to form a catalyst coated membrane (CCM). A CCM fuel cell can include platinum, ruthenium, and other catalytic elements. In another type of fuel cell, the anode and cathode catalyst materials are coated onto their respective carbonaceous gas diffusion layers toto form gas diffusion electrodes (GDE), which are then sandwiched around the PEM. A GDE fuel cell can also include platinum, ruthenium, and other catalytic elements. The gas diffusion layers provide for the uniform distribution of hydrogen and oxygen to their respective sides of the PEM, provide a conductive pathway for electricity to be transmitted out of the fuel cell, and provide a porous means for the water produced by the electrochemical reaction to be transported away.
Another type of fuel cell using catalytic elements such as platinum is an alkaline fuel cell (AFC). Still another type of fuel cell using catalysts is a phosphoric acid fuel cells (PAFC), which use a poly-benzylimidazole (PBI) membrane saturated with phosphoric acid electrolyte. Regardless of the type, after a period of use, a fuel cell often must be replaced, due to fouling of the catalyst, or for another reason. In particular, after repeated cycling of the fuel cell during operation (i.e., cycling between periods of high and low voltage generation), the catalyst can tend to migrate into the membrane and the catalytic element particles can become altered in size and therefore less effective. Rather than simply disposing of a fuel cell that must be replaced, it is highly desirable to recover as much catalytic element as possible from the MEA, due to the value of the precious metal.
The conventional approach to recover platinum and other precious metal catalytic elements from an MEA includes combusting the PEM and the carbonaceous diffusion layers, dissolving the resultant ash in acid, and purifying the precious metal using standard refining chemistry. However, the high fluorine content of the MEA, particularly those with Nafion™ or other Teflon™-based membranes, results in toxic emissions of hydrogen fluoride gas (HF) and other fluorine compounds from the combustion process.
To dissolve and recover the platinum catalyst, the majority of available methods use hydrochloric acid leaching media assisted by a chemical oxidant such as nitric acid (i.e. aqua regia), halogen gas (e.g. Cl2, Br2), and even hydrogen peroxide [1,2]. The platinum chloro complexes thus obtained are subsequently extracted by solvent extraction processing, stripped from the organic phase by water and possibly precipitated as (NH4)2PtCl6 in fairly high purity (99.95%) by addition of ammonium chloride to the aqueous phase [3]. Possible emissions to air from this type of processing include ammonia, chlorine, hydrogen chloride and nitrogen dioxide. The described industrial process is, seemingly, designed with the intention of recovering the noble metal catalyst as pure salts that can be traded. This line of thought is also followed in platinum catalyst recycling schemes specifically considered for polymer electrolyte membrane fuel cells [4-8].
Several methods exist for the preparation of supported and unsupported noble metal catalysts based on these commercially available salts [9].
EP0363314A1 describes a method for recovery of precious metals such as platinum, palladium and rhodium used as catalysts. The method comprises dissolving the metals by placing them in a solution comprising an electrolyte such as hydrochloric acid and electrolysing the solution. The pure metals are precipitated by adding a reducing agent to the solution. EP0363314A1 does not disclose an integrated process for obtaining the metals in a catalytic structure.
There is a need for a more simple method for recovery of precious metals in catalytic structures.

Method for recovering platinum group metals from catalytic structures


A protrusion provided at one end of a first fitting body is engaged with one of the recesses in a plurality of grooves provided at one end of a second fitting body in the lengthwise direction, whereby the degree of overlapping between the first fitting body and the second fitting body is adjusted. Then, the other end of the first fitting body and the other end of the second fitting body engaging with the recesses and protrusions of a fluted portion of a sensor portion are fixed with a fixing screw. Thus, the other end of the first fitting body and the other end of the second fitting body are drawn near to each other, and a fitting for a bicycle is firmly fixed to the fork or other part thereof.

1. Field of the Invention
The present invention relates generally to fittings for a bicycle, and more specifically, to a fitting for a bicycle for mounting a device for bicycle such as a meter and a sensor on a component of a bicycle such as a handle and fork.
2. Description of the Background Art
In recent years, bicycles are sometimes provided with speed meters so that cyclists can be easily informed of travel speed, travel distance or the like.
FIG. 6 is a side view showing such a speed meter mounted on a bicycle, FIG. 7 is a view showing encircled portion "X" in FIG. 6 being enlarged, and FIG. 8 is an enlarged cross sectional view taken along line VIII--VIII in FIG. 7.
Referring to FIGS. 6 and 7, a speed meter 30 is mounted on the stem 31 of the handle of a bicycle 24. Front spokes 32 of bicycle 24 are provided with a magnet 26, and the portion of fork 34 corresponding to magnet 26 is provided with a sensor portion 28 for generating a signal every time magnet 26 passes in front of it.
The signal generated by sensor portion 28 is input to speed meter 30 through a cord 11, various operations are performed based on the signal in the meter, and information such as speed and travel distance is given to the user.
Now, referring to FIG. 8, how sensor portion 28 is mounted on fork 34 will be described.
A fitting for bicycle 36 for mounting sensor portion 28 on fork 34 includes a band-shaped fitting body 38 which can be engaged with the grooves and ridges of the fluted portion of sensor 28 on the outer periphery of one open end 25, a packing 40 fit along the inner circumference of fitting body 38, and a fitting screw 42 for fixing one end 25 of fitting body 38 engaged with sensor portion 28 and the other end 27.
Packing 40 is fit along the inner circumference of band-shaped fitting body 38, then both ends of fitting body 38 are opened to be fit around fork 34, and packing 40 will be fit along the inner circumference of fitting body 38 and the outer circumference of fork 34. Sensor portion 28 and the grooves and ridges of the fluted portion at one end 25 of fitting body 38 are engaged with each other, and then the one end 25 and the other end 27 of fitting body 38 and sensor portion 28 are fixed by fitting screw 42. Fitting body 38 is tightened to forks 34 through packing 40, and therefore sensor portion 28 will be fixed to fork 34 by means of fitting for bicycle 36.
Meanwhile, unlike such fitting for bicycle 36 using the fitting screw and the packing, there are fittings for bicycles of cord band type.
FIG. 9 is a perspective view showing how a sensor portion is mounted on a fork with a conventional fitting for bicycles of the cord band type, FIG. 10 is an enlarged cross sectional view taken along line X--X in FIG. 9, and FIG. 11 is an enlarged cross sectional view taken along line XI--XI in FIG. 9.
Referring to FIGS. 9 to 11, a fitting for a bicycle of the cord band type 44 for mounting a sensor portion 29 on a fork 34 includes an integral structure of cord band portions 46a, 46b having a shape like a cord band for bundling the cord of an electrical appliance, and a sensor portion 29. Cord band portion 46b has grooves and ridges of corrugation lengthwise on its outer circumference, and an engaging portion 48 having a protrusion 45 which can be engaged with one of the grooves of the corrugation is provided at an end of cord band portion 46a.
When mounted, engaging portion 48 is manually pressed and the end of cord band portion 46b on the side having the grooves and ridges of corrugation is pulled through engaging portion 48. Thus, the protrusion 45 of engaging portion 48 is gradually engaged with a groove of corrugation of cord band portion 46b near sensor portion 29, then the inner circumference of cord band portion 46b is pressure-contacted to fork 34 and sensor portion 29 is fixed to fork 34.
There are more than one kinds of shapes for the fork of a bicycle, and the forks of so-called mountain bikes are for example often larger than the forks of sports bikes.
The former fitting for a bicycle with a fitting screw and a packing can be adapted to forks of different sizes by changing the thickness of the packing to a limited extent, and fittings of different sizes such as large, medium and small must be usually prepared for one component for a bicycle.
Meanwhile, the latter fitting for a bicycle of cord band type can cope with forks of different sizes by adjusting the degree of tightening the cord band portion. However, since it is tightened in a stepped manner by each groove of corrugation, fine adjustment such as done with the screw type cannot be made. If the protrusion in engagement with one of the grooves of the corrugation is forced to engage with another groove closer to the sensor portion, the cord band portion can be cut away from the sensor portion. Furthermore, since the engaging force between the protrusion and the groove of the corrugation of cord band portion engaging therewith at the engagement portion is constant, tightening too much degrades the reliability of the engaged portion.

Band-shaped fitting for a bicycle mounted on a component of a bicycle


A current-mode analog-to-digital (IADC) has subnA sensitivity. An IADC cell receives an input current signal and provides an output to a comparator for comparison with an adjustable input reference signal. A digital output signal is generated and an analog output is provided to the next cell.

As is known in the art, analog-to-digital converters (ADCs) convert a signal in analog format to a signal in digital format. Conventional ADC circuits can have a variety of circuit architectures each of which has certain concomitant disadvantages. Known ADC architectures include pipeline, sigma-delta, cyclic, flash, successive approximation, and dual-slope. Each ADC architecture is generally applicable to a limited operating range. That is, each of these architectures has strengths and weaknesses that make them more amenable to working in certain frequency and resolution ranges.
Some ADC architectures do not operate outside certain ranges or consume prohibitively high power in certain ranges as compared to other architectures. Even within preferred operating ranges, a given architecture can have a performance level that is dictated by certain circuit parameters that are fixed for a given design.
High-performance analog-to-digital converters (ADCs) are generally optimized for conversion speed and resolution with a given size and power budget. In CMOS-based mobile biochemical sensor application, however, speed and resolution are immaterial because of the slow reaction rates (>seconds) and inherent experimental errors (˜10%) typical of most biochemical reactions. Instead, ADC sensitivity, power consumption and size may be of greater interest.
In one known attempt to apply ADCs to biochemical reactions, to convert sub-nA level photo currents into voltage, the input signal is amplified using large-gain (106) current mirrors, increasing power and area requirements and the current mirror's susceptibility to mismatch errors for a given chip area, as disclosed in U. Lu, Hu, B. C-P., Shih, Y-C., Wu, C-Y, and Yang, Y-S, "The design of a novel complementary metal oxide semiconductor detection system for biochemical luminescence," Biosensors and Bioelectronics, vol. 19, pp. 1185-1191, 2004, which is incorporated herein by reference.
In M. Simpson, Sayler, G, Patterson, G, Nivens, E, Bolton, E., Rochells, J., Arnott, J, Applegate, B., Ripp, S., and Guillom, M., "An integrated CMOS microluminometer for low-level luminescence sensing in the bioluminescent bioreporter integrated circuit," Sensors and Actuators B, vol. 72, pp. 134-140, 2002, which is incorporated herein by reference, increased ADC sensitivity was achieved by successive capacitive integration and voltage-to-frequency conversion at the expense of increased power consumption and long conversion time (˜ seconds).

Method and apparatus for current-mode ADC


The present invention refers to a robot, a docking system and a docking method therefor. The docking system comprises a first circuit located in a robot. The first circuit comprises a power storage unit for supplying power to the robot and a first main control unit for controlling the movement of the robot. The docking system further comprises a first group of terminals electrically connected with the first circuit, and a second circuit located in a docking station. The second circuit comprises a power supplying unit. The docking system further comprises a second group of terminals electrically connected with the second circuit. The power storage unit or the power supplying unit provides a detection power. The detection power generates a detection current when it flows across a detection circuit. The detection circuit is constructed by the first circuit and the second circuit through the first group of terminals docking with the second group of terminals. The detection circuit further comprises a current detection unit, and the first main control unit confirms that the first group of terminals dock with the second group of terminals when the detection current is detected by the current detection unit. The robot according to this invention can reliably dock to the docking station without human intervention, which brings extreme convenience to production and life.

Along with the development of scientific technology, intelligent robots have become known to people. The robots can implement the related predetermined tasks without manual operation and interference according to the predetermined programs, and therefore are widely applied to industrial and household products; such as robots conducting various functions, lawn mowers, and dust collectors. The intelligent robots greatly save time for people and bring great convenience to industrial production and household living. Those robots adopt a power storage unit to supply power, but when the power in the power storage unit is exhausted, they cannot work. At this moment, people have to move the robots to the docking station to supplement power. In some circumstances, power supplementation may cost several hours, so people have to wait for several hours before re-starting the robots and having it work continuously.
To overcome the mentioned problems, a system and a method for automatic docking of the robots and docking station must be developed.

Robot, a docking system and a docking method


One or more computing devices, systems, and/or methods for cross-domain action prediction are provided. Action sequence embeddings are generated based upon a textual embedding and a graph embedding utilizing past user action sequences corresponding to sequences of past actions performed by users across a plurality of domains. An autoencoder is trained to utilize the action sequence embeddings to project the action sequence embeddings to obtain intent space vectors. A service switch classifier is trained using the intent space vectors. In response to the service switch classifier predicting that a current user will switch from a current domain to a next domain, the current user is provided with a recommendation of an action corresponding to the next domain.

Many users may perform tasks across a variety of services, applications, platforms, and/or websites corresponding to different types of domains, such as a news application having a news domain, a shopping website having a shopping domain, a social network service having a social networking domain, etc. For example, a user may utilize a user device to access the news application having the news domain. The user may read various articles pertaining to topics that may be interesting to the user, such as an article about a basketball playoff game. Based upon actions performed by the user while in the news domain (e.g., reading articles about basketball), the user may decide to transition to a different domain, such as the shopping website having the shopping domain. While accessing the shopping website, the user may perform an action such as purchasing a basketball jersey because the user recently read the basketball articles while in the news domain.