Triacetone triperoxide (TATP) and other explosives of the peroxide family are safely degraded in situ. Nano and micron size metal particles in an elemental state include pure iron and magnesium or iron and magnesium particles that are mechanically alloyed with palladium and nickel. The metal particles are used in both the elemental state and in emulsions that are made from water, a hydrophobic solvent, such as corn oil, and a food-grade nonionic surfactant. The neat metals and emulsified zero valent metals (EZVM) safely degrade TATP with the major degradation product being acetone. The EZVM system absorbs and dissolves the TATP into the emulsion droplets where TATP degradation occurs. EZVM systems are ideal for degrading dry TATP crystals that may be present on a carpet or door entrance. Both the neat metal system and the emulsion system (EZVM) degrade TATP in an aqueous slurry.

In the 19th century a German scientist, R. Wolffenstein, discovered acetone peroxide using an inorganic acid as a catalyst and received a patent on its use as an explosive. Acetone peroxide is noted for its instability and thus, for more than 100 years was not used militarily or commercially. However, in the 21st century man's evil twin has embraced acetone peroxide as a weapon of choice for terrorist activities and suicide bombers.
Triacetone triperoxide (TATP) and other explosives of the peroxide family are used extensively by terrorist organizations around the world because they are easy to prepare and very difficult to detect. TATP can be made from common household items such as drain cleaner (sulfuric acid —H2SO4), hydrogen peroxide (H2O2), and acetone (CH3COCH3), a nail polish remover and common organic solvent. The low cost of the reactants and the ease with which they can be obtained lead to the manufacture of TATP by those without the resources to manufacture or buy more sophisticated explosives.
The acid-catalyzed peroxidation of acetone produces a mixture of dimeric and trimeric forms. The trimer is the more stable form, but not much more so than the dimer. All forms of acetone peroxide are insoluble in water and very sensitive to initiation. Organic peroxides are sensitive, dangerous explosives. The military does not use them because there are many better alternatives. For people who synthesize homemade explosives, there are far safer alternatives. Even nitroglycerin is not as sensitive as acetone peroxide. TATP is highly unstable and sensitive to heat and friction and is well deserving of the nickname, "Mother of Satan."
Global security, travel, human and animal life are threatened. The world population is at increased risk of adverse outcomes, including constant fear, terror and death.
As an illustration of the gravity of the situation, on Dec. 22, 2001, American Airlines Flight 53, carrying a crew of 14 and a passenger complement of 184, including "shoe bomber" Richard Reid, departed Charles de Gaulle Airport in Paris, France, bound for Miami, Fla. Approximately one and a half hours into the flight, a flight attendant smelled what she thought was a burnt match. After the flight attendant determined that it was coming from where Reid was seated, she confronted Reid, at which time he put a match into his mouth. The flight attendant alerted the captain over the intercom system. Reid went on to light another match in an apparent attempt to set fire to his shoe. The flight attendant then noticed a wire protruding from the shoe. A struggle ensued among several of the flight attendants, passengers and Reid. Ultimately Reid was subdued and restrained for the remainder of the flight. The flight was diverted for landing to Boston's Logan International Airport where Reid was taken into federal custody. Later, analysis by the FBI laboratory in Washington determined that there were two functional improvised explosive devices hidden in Reid's shoes made of the explosive material triacetone triperoxide, known as "TATP," and other components. Richard Reid's shoe had 8 or 10 ounces of triacetone triperoxide and PETN, a high grade military plastic explosive.
The instability of triacetone triperoxide, as mentioned earlier, makes the remediation of a contaminated area a challenging problem. Thus, the best solution is to use a methodology wherein the TATP is degraded in place, to the point where it is safe to remove and/or that it is completely degraded. Such a methodology would have global demand and could be used to abate the crises caused by "shoe bombers" on airplanes or "suicide bombers" in hotels, restaurants or on the streets.
The following US Patents are related to degradation or removal of deleterious materials, including explosives.
U.S. Pat. No. 4,641,566 to Pomeroy teaches an in situ method for detecting buried land mines by non-destructive means involving the spraying of a suspected area with a leach of ionized metal and leaching the ionized metal into the soil to leave a metallic concentrate on an impervious object, such as a plastic mine; then, scanning the area with a metal detector.
U.S. Pat. No. 4,908,323 to Werner discloses a method for determining organic peroxides in aqueous and organic solutions using a peroxide detecting amount of a titanium (IV) compound.
U.S. Pat. No. 5,434,336 to Adams et al. describes an in situ process for the destruction of explosives by heating in the presence of elemental sulfur at temperatures below their spontaneous decomposition temperatures.
U.S. Pat. No. 6,664,298 to Reinhart et al. describes the in situ use of a zero-valent metal emulsion to dehalogenate solvents, such as, trichloroethylene (TCE) and other halogentated hydrocarbons that contaminate ground water and soil environments. The preferred zero-valent metal particles are nanoscale and microscale iron particles. U.S. Pat. No. 6,767,717 to Itzhaky et al. describes a method of detecting a peroxide-based explosive in a sample suspected of having such an explosive; the method includes dissolving the sample in an organic solvent, then contacting the solution with an aqueous solution of a strong acid capable of decomposing the explosive to release hydrogen peroxide, and further contacting the mixture with a peroxidase enzyme to produce a pronounced change in the color of the substrate or its color intensity.
U.S. Pat. No. 6,773,674 to Bannister et al. describes methods and systems for detecting the presence of an energetic material, such as triacetone triperoxide (TATP), in a sample which is known to have the energetic material using thermal analysis for detecting and identifying explosives and other controlled substances. This method requires moving the explosive materials to a laboratory with appropriate analytical equipment.
U.S. Pat. No. 7,077,044 to Badger et al. discloses a method for bioremediating undetonated explosive devices by mixing an explosive mixture with microorganisms.
U.S. Pat. No. 7,159,463 to Dayagi et al. discloses a sensitive and selective method and device for the detection of trace amounts of a substance. A piezoelectric crystal element is used in a sensor device for identifying at least one foreign material from the environment.
WO1999/043846 to Keinan et al. discloses a method and kit for the detection of explosives. The method relies on the decomposition of TATP in the presence of concentrated aqueous sulfuric acid to produce hydrogen peroxide, which is detected by horseradish peroxidase and a color-change reagent.
J. A. Bellamy in J. Forensic Science 1999, 44(3), 603-608 reports that solutions of TATP in acetone and other organic solvents have been known to detonate, although solutions in toluene appear to be somewhat stable. It is therefore a risky proposition to dissolve the explosive in organic solvent in an attempt to remove it if no remediaton step is involved.
Irradiation with UV light has been used as a method of decomposing TATP in a detection scheme involving horseradish peroxidase/indicator combination as reported by R. Shulte-Ladbeck, et al. in "Trace Analysis of Peroxide-Based Explosives" Analytical Chemistry 2003, 75, 731-735.
The thermal decomposition of TATP has been found to have an activation energy which is within the reasonable expectation for a unimolecular decomposition initiated by a peroxide bond homolysis according to J. C. Oxley et al. in "Decomposition of a Multi-Peroxidic Compound Triacetone Triperoxide (TATP)" Propellants, Explosives, Pyrotechnics, 2002, 27, 209-216. Thermal decomposition of TATP in refluxing toluene has been found to be a slow process as reported by N. A. Milas et al. in "Studies in Organic Peroxides XXIV. Preparation, Separation and Identification of Peroxides Derived from Diethyl Ketone and Hydrogen Peroxide." J. Am. Chem. Soc. 1959, 82, 3361-3364.
The complexation of TATP with ions was investigated by F. Dubnikova, et al. and many ions are calculated to form stable complexes with the explosive, as reported in "Novel Approach to the Detection of Triacetone Triperoxide (TATP): Its Structure and Its Complexes with Ions" J. Phys. Chem. A2002, 106, 4951-4956.
Further research is available on the use of nano-size elemental metal particles, such as, iron in emulsion systems capable of degrading chlorinated hydrocarbons in a controlled manner, the use of nanometal particles in emulsion systems where the reductive reactions take place within an emulsion droplet and where the hydrophilic and hydrophobic properties of the skin of the droplet can be controlled to a level so as to facilitate the entrance of the molecule of choice that is to be degraded. See C. L. Geiger, et al. "Nanoscale and Microscale Iron Emulsions for Treating DNAPL." in: Innovative Strategies for the Remediation of Chlorinated Solvents and DNAPL in the Subsurface. Series 837, 2002, ACS Books, Washington D.C. Jacqueline Quinn, et al. "Evaluating The Distribution Of Emulsified Zero-Valent Iron For Four Different Injection Techniques," Remediation of Chlorinated and Recalcitrant Compounds 2004, May 2004. Battelle Press, ISBN #1-57477-132-9. Jacqueline Quinn, et al. "Field Demonstration of DNAPL Dehalogenation Using Emulsified Zero-Valent Iron," 2005, Environ. Sci. Technol. 2005; 39(5); 1309-1318.
Kristen Milum, et al. in "In Situ Heavy Metal Contaminant Removal Using Emulsified Iron," Remediation of Chlorinated and Recalcitrant Compounds 2004, May 2004. Battelle Press, ISBN #1-57477-132-9 discuss various complexing agents that can be added along with nano-size metal particles into the emulsion system.
Collectively, the above references do not provide a composition of matter and in situ methodologies that safely degrade triacetone triperoxide (TATP) and other organic peroxides that are "homemade" weapons of choice used by 21st century terrorists and extremists. There is a great need for a composition and method that provides safe and effective means for in situ degradation of explosive materials; the present state of the art does not meet this need.

Safe, in situ methodologies for the destruction of triacetone triperoxide and other explosive peroxides

University of Central Florida Research Foundation, Inc.


Herein are described an instrument and a method for using the same. The instrument comprises a fluid channel fluidly connected to at least a first fluid reservoir and a second fluid reservoir; a counter electrode (CE), a reference electrode (RE), and a working electrode (WE); and a potentiostat. The CE, RE, and WE are all disposed within the fluid channel; the potentiostat is isolated from earth ground by at least one isolator and is powered by a floating power supply; and the CE, RE, and WE are each electrically connected to the potentiostat.

Field
The present disclosure relates to an instrument and method for performing electrochemistry.
Description of Related Art
The ability to perform electrochemical detection in the presence of large voltages and electric field magnitudes without concern for the local potential has many possible applications in micro/nanofluidic assays and in capillary electrophoresis. Traditionally, electrochemical detection (also, "electrochemistry" herein) in the presence of significant external electric fields has been dominated by end-channel detection for capillary and microchip electrophoresis detection.
A second, common, approach to performing electrochemical measurements in large electric fields is to utilize bipolar electrodes (BPEs), i.e., electrically floating metal electrodes placed in the high-field environment, which drive electrochemical reactions based on the local potential difference between the electrode and solution. BPEs have been used for redox reactions as diverse as electrogenerated chemiluminescence and silver dissolution and have been used for applications like catalyst evaluation and concentration enrichment. Another structure-based strategy to couple electrochemistry with electrokinetic flow involves nanostructured solid-state architectures with arrays of nanocapillaries presenting embedded annular electrodes. These embedded annular nanoband electrode arrays achieve high fields at low voltages by placing the working electrode a few μm from the counter electrode and, thus, support electrokinetically-driven enhanced mass transport for electrochemical processing.
Lunte, Martin, Wightman and others have pioneered a variety of strategies for in-channel electrochemical detection at high fields, for example, in microchip capillary electrophoresis applications. These include decoupling the electric field, dual-channel detection, and the development of isolated potentiostats. Previous iterations of isolated potentiostats have allowed in-channel detection in external electric fields by placing the working electrode (WE) in-channel, while the reference (RE) and counter (CE) electrodes are placed in a field-free volume, for example, in the buffer well at ground potential. While this works very well and is straightforward to fabricate, it limits the placement of the WE, because of iR-derived shifts in the actual potential,EActual=EApplied−iR  (1).
As the WE is moved further into the channel, the iR drop increases, causing large shifts in the actual potential at the WE compared to the nominal applied potential. This presents unique challenges for designing electrochemical devices, which incorporate electrokinetic flow. Decoupling the WE from the field in the microchannel greatly mitigates problems with iR drop and voltage shifts, but at the expense of increased dead volume and degraded peak shapes. In addition, some previous approaches have grounded the RE, but this would clearly present problems if the RE is placed in the middle of a channel at high voltage.
Ideally, one would like to perform voltammetry, as opposed to measurements at a single potential, in LOC devices and to do it independent of local potential or field strength, without shifting the observed potential of the voltammetric features. Approaches to this ideal have been achieved in certain special cases. For example, mid-channel detection has been demonstrated at field strengths up to 400 V cm−1 by incorporating a polyelectrolyte gel salt bridge into a microfluidic device to separate the WE in the channel from the RE and CE.


An anhydrous topical composition provides a water repellent surface. The anhydrous topical composition has at least one film former with surface tension lower than 35 dynes/cm, at least one particle having a hydrophobic surface or a hydrophobic surface treatment, and a volatile topical carrier.

Field of the Invention
The invention involves chemical compositions capable of repelling water. Specifically, the invention involves chemical compositions, safe for application to human skin, capable of repelling water by imparting hydrophobic of superhydrophobic characteristics into topical formulae.
Description of Related Art
Water repellency or durability is one of key performance characteristics in certain topical compositions including long-wearing color cosmetics and water resistant sunscreens. Conventional technologies in cosmetics and sunscreens have focused on staying power on skin, such as long-lasting skin adhesion or water resistance of cosmetic actives. Many film formers have been used to enhance the durability of cosmetic and other topical compositions on human skin. Typically, when a topical composition is exposed to water, such as through sweating or swimming, the water starts to wet the composition surface. A wet surface ultimately results in a lack of durability in a topical composition. This lack of durability is caused by a loss of topical actives due to any re-emulsification process.
Past compositions attempted to create water resistant surfaces, whereas hydrophobic or superhydrophobic technology creates a water repellent surface. A water repellent surface creates a physical interaction with water molecules, so that water will bead up and roll off the topical surface without wetting the surface. Water repellency not only provides a desirable dry feel on skin but also creates a visual cue for formula durability on skin.
Hydrophobicity is measured by the water contact angle. The water contact angle on a surface is the angle of the leading edge of a water droplet on the surface as measured from the center of the interface between the droplet and the surface. A surface with a contact angle of 180 degrees means that water sits on the surface as a perfect sphere. Hydrophobic surfaces, when measured, have a contact angle between 90 degrees and 150 degrees. Superhydrophobic surfaces, when measured, have a contact angle between 150 degrees and 180 degrees.
A superhydrophobic surface can cause water to roll off the surface leaving little or no residue. Hydrophobic surfaces are desirable in many arts for varied uses and are created through varying means. For example, a superhydrophobic surface can be created on polytetrafluoroethylene (PTFE) with a picosecond laser for use on underwater materials (Shang et al., "Nanostructured Superhydrophobic Surfaces," 40 J. MATER . Sci. . 3587 (2005)). Carbon nanotubules also can achieve a superhydrophobic surface through deoxygenation of a chemical treatment (Lau et al., "Superhydrophobic Carbon Nanotube Forests," 3 NANO LETTERS 1701 (2003); U.S. Pat. No. 9,115,424). Additionally, acid absorbed onto aluminum coated in polyethyleneimine (PEI) can create a superhydrophobic surface (Ren et al., "Preparation and Characterization of an Ultrahydrophobic Surface Based on a Stearic Acid Self-Assembled Monolayer over Polyethyleneimine Thin Films," 546 SURFACE SCIENCE 64 (2003)).
Film formers are known to be used in topical compositions to create water resistant barriers. Film formers are durable water resistant polymers that have wide use in industrial processes. When applied to a surface, film formers act as a barrier between the surface and any outside matter, such as water. Film formers are commercially available in many different forms. Emulsion-based film formers are typically water-in-oil or water-in-silicone emulsions. The use of such emulsions relies on the water evaporating and leaving the oil or the silicone in contact with the skin to produce a water resistant layer. However, the use of emulsion-based film formers creates unpleasant aesthetics on the skin, such as an oily appearance and a greasy feel. The resulting film is not water repellent and leaves an unnatural appearance on the skin.
Anhydrous film formers typically include organic solvents, such as an alcohol. Such film formers can also produce a tacky feeling on human skin and other undesirable aesthetics when introduced to water. Representative patents regarding such water resistant topical compositions are set forth below in Table 1.
TABLE 11U.S. Pat. No. 5,985,297Anhydrous and water-resistant cosmeticcompositions2U.S. Pat. No. 5,925,337Waterproof compositions for coveringthe eyelashes, and process for thepreparation thereof3U.S. Pat. No. 4,795,631Water based lip color comprising analkali soluble film-forming agent
Film formers conventionally used in topical compositions alone do not reach a desirable level of hydrophobicity that imparts durability. Ideally, a topical composition has a superhydrophobic surface that creates a water contact angle of 150 degrees or more. Table 2 below shows that most film formers alone can barely achieve a water contact angle greater than 100 degrees, while it is desirable to achieve a surface hydrophobicity where the contact angle of water is 130 degrees or greater. It should also be noted that upon incorporation into a topical composition with various other ingredients, such contact angles are difficult to maintain.
TABLE 2γS CriticalContactSurfaceAngleTensionwithPolymer NameCAS No.(dynes/cm)Water (°)Polyvinyl alcohol (PVOH)25213-24-53751Nylon 6 (polycaprolactum,25038-54-443.962.6aramid 6)Polyethylene oxide (PEO, PEG)25322-68-34363Polymethylmethacrylate9011-14-737.570.9(PMMA, acrylic)Polystyrene (PS)9003-53-63487.4Polybutadiene9003-17-229.396Polyethylene (PE)9002-88-431.696Polydimethylsiloxane (PDMS)9016-00-620.1107.2Paraffin (Wax)8002-74-224.8108.9Polytetrafluoroethylene (PTFE)9002-84-019.4109.2Polyisobutylene (PIB, butyl9003-27-427112.1rubber)
Despite the many advances in water resistant topical compositions, there is still a need for a water repellent topical composition that provides pleasant and desirable aesthetics for consumers.

Hydrophobic topical compositions and methods for producing same


The present invention provides a polynucleotide (hjak2) which identifies and encodes a novel human Jak2 kinase (HJAK2) which was expressed in the placenta. The present invention also provides for antisense molecules and oligomers designed from the nucleotide sequence or its antisense. The invention further provides genetically engineered expression vectors and host cells for the production of purified HJAK2 peptide, antibodies capable of binding to HJAK2, inhibitors which bind to HJAK2 and pharmaceutical compositions based on HJAK2 specific antibodies or inhibitors. The invention specifically provides for diagnostic assays based on altered hjak2 expression and which allow identification of such a condition. These assays utilize probes which comprise oligomers, fragments, or portions of hjak2 or its regulatory elements or antibodies specifically binding HJAK2.

JAK kinases are Janus family nonreceptor protein-tyrosine kinases (NR-PTK) that lack transmembrane regions and form functional complexes with the intercellular regions of other cell surface receptors. They were first identified as the products of mutant oncogenes in cancer cells where their activation was no longer subject to normal cellular controls. Described JAK kinases include Jak1, Jak2, and Jak3, which all share the conserved kinase domain. In addition, these proteins have 5 to 100 amino acid residues located on either side of, or inserted into loops of, the carboxyterminal kinase domain which allow the regulation of each kinase as it recognizes and interacts with its target protein. Known target proteins include growth hormone receptor, prolactin receptor, erythropoietin receptor, cytokine receptors and others which utilize the common chain known as gp130. These receptors are unique both in their ability to recruit multiple PTKs and in the diversity of their responses within different cell types (Taniguchi T (1995) Science 268:251–55). Genetic evidence places these kinases in the interferon α and γ signal transduction pathways which are widely expressed in mammalian cells.
Kinases regulate many different cell proliferation, differentiation, and signaling processes by adding phosphate groups to proteins. The high energy phosphate which drives activation is generally transferred from adenosine triphosphate molecules (ATP) to a particular protein by the PTKs, and the transfer process is roughly analogous to turning on a molecular switch. When the switch goes on, the kinase activates a metabolic enzyme, regulatory protein, receptor, cytoskeletal protein, ion channel or pump, transcription factor, or another kinase. For example, in their normal role, the JAK NR-PTKs are capable of regulating tyrosine phosphorylation of STAT proteins, signal transducers and activators of transcription, such that they translocate to the nucleus and bind DNA (David M et al. (1995) Science 269:1721–1723). In contrast, uncontrolled kinase signaling has been implicated in inflammation, oncogenesis, arteriosclerosis, and psoriasis.
Almost all kinases contain a similar 250–300 amino acid catalytic domain. The N-terminal domain generally folds into a two-lobed structure to bind and orient ATP (or GTP) donor molecules. The larger C terminal lobe binds the protein substrate and carries out the transfer of phosphate from ATP to the hydroxyl group of a tyrosine residue. The primary structure of the kinase domain is conserved in the residues: G50 and G52 in subdomain I, K72 in subdomain II, G91 in subdomain III, E208 in subdomain VIII, D220 and G225, in subdomain IX, and the amino acid motifs of subdomain VIB, VIII and IX (Hardie G and Hanks S (1995) Academic Press, San Diego Calif.).
The novel human Jak2 kinase, hjak2, of the present application shows significant conservation of the diagnostic kinase residues which allowed its identification from among the isolated cDNAs of a placenta library, the anatomy and physiology of which is briefly described below.
The placenta is a thickened disk-shaped temporary organ that interchanges gases, nutrients, hormones, excretory products, humoral antibodies (IgG), and any other circulating substances between the maternal and fetal bloodstreams. Receptors facilitate the transport of glucose, amino acids, and IgG directly from maternal blood to fetal blood. The placenta is the only organ composed of cells derived from two individuals, the fetal extraembryonic chorion and the maternal endometrium. The boundary between these two tissues is marked by extracellular products of necrosis referred to as fibrinoid. This boundary results from the various tissue interactions, immunological responses, etc. which occur in the placenta.
The major tissue interaction involves the expression of paternal antigens by the chorionic villi which is directly adjacent to maternal blood. Although the mother initiates an immunological response, fetal tissue is not typically rejected. This is attributed to the fact that the fetus only expresses major histocompatibility complex (MHC) I, and not MHC II which is the major cause of organ allograft rejection. In addition, uterine secretions during early gestation contain significant amounts of glucose and glycoproteins which may participate in local immunosuppression. Although infections by bacteria, viruses, mycoplasmas, or parasites may ascend from the endocervical canal or reach the placenta through maternal blood, they rarely cause gross pathological changes because of maternal immune defense.
Soon after implantation, fetal villi begin to control maternal physiology to create an optimal environment for development. This involves the production of chorionic gonadotropin, estrogen and progesterone, chorionic somatomammotropin, insulin-like growth factors, platelet derived growth factor, prolactin, and various cytokines. These and other factors such as hjak2 certainly regulate the numerous activities (respiratory, immunological, gastrointestinal, and urinary) which occur within the placenta and between maternal and fetal tissues.
The anatomy and physiology of human placenta is reviewed, inter alia, in Benirschke and Kaufmann, (1992) Pathology of the Human Placenta, Springer-Verlag, New York N.Y., pp. 542–635; Herrera Gonzalez and Dresser (1993) Dev Comp Immunol 17(1):1–18; Mitchell et al. (1993) Placenta 14:249–275; Naeye (1992) Disorders of the Placenta, Fetus, and Neonate; Diagnosis and Clinical Significance, Moseby Year Book, St. Louis Mo.; and Rutanen (1993) Ann Med 25:343–347.

This patent is subject to a terminal disclaimer.


A conductivity cell for use in determining ionic concentrations in the gap between two semiconductor substrates or wafers. The wafer gap conductivity cell is composed of two flat electrodes separated by a fixed gap. The electrodes are fabricated from wafers of the same type and dimensions used as semiconductor device substrates. All or a portion of the surfaces of the wafer electrodes are coated with a conductive material. The wafer gap conductivity cell is placed in a wafer cassette or other suitable wafer holder, whose other slots are filled with wafers which are to be cleaned or subjected to another fabrication process. The cell can be used to characterize the processes used during the fabrication of semiconductor devices and assist in investigating the effect on the processes of different process vessel designs.

Process vessels are tanks or other containers used in the semiconductor industry as part of the device fabrication process. Process vessels are the containers in which fabrication processes such as the etching, cleaning, stripping, and rinsing of semiconductor wafers are carried out. One type of process vessel, termed a rinse tank, is used during the cleaning of the substrates or wafers on which devices are to be fabricated. The cleaning process removes particles and contaminants acquired during manufacture of the wafers. This is necessary because the presence of contaminants or residues on a substrate can adversely affect the electrical characteristics and yield of the fabricated devices.
During a cleaning process, the substrates or wafers are typically placed in a slotted cassette (sometimes termed a "boat") which is placed in a tank (process vessel) containing a cleaning agent, typically an acid bath. The acid bath is commonly formed from a mixture of an oxidant species and an acid. After immersion in the acid bath, the cassette is transferred to a rinse tank in which the treated wafers are rinsed in ultrapure water. The rinsing step is designed to quench the wafers, so that the acid solution does not continue to act on the wafers, and to dilute and remove the chemical residues from the wafer surface.
Continual efforts are made in the semiconductor industry to improve rinse tank designs in order to reduce rinse water consumption and increase wafer throughput. This is especially important as the number of device fabrication steps and wafer size increase. These efforts generally involve making measurements to determine how quickly and completely the contaminants and oxidant solution are removed from the surface of the wafers during the rinse process. Methods currently employed to improve rinse tank and rinse process efficiency include minimizing the tank volume, reducing the wetted surface area by use of a reduced cassette, utilizing dilute chemistries, and increasing the temperature of the rinse water.
In addition, rinse tank structure designs can be optimized through the use of computational fluid dynamics, followed by experimental verification. To date, most published data used to characterize and model the rinse process within a rinse tank (or another fabrication process being carried out in a different process vessel) has been acquired by means of a wall mounted conductivity probe. While this provides useful information, there are many drawbacks to wall mounted probes: 1) The probe does not provide a direct measurement of the conductivity (and by inference, ion concentration) in the wafer gap between two wafers; 2) Probe performance is affected by changes in tank configuration and flow field; and 3) The probe response to different carry over chemistries does not correlate quantitatively to the amount of carry over on the wafer during rinsing. Because the placement of the probe on a tank wall interferes with the normal fluid flow within the rinse tank, the measurements obtained in this manner contain an inherent source of error as they are based on a disturbed tank flow and are measured at a location way from the surface of interest.
Other process vessels, such as those used to perform etching or photoresist stripping stages of the fabrication process are also candidates for investigation and design improvements. In order to improve such process vessels and the related fabrication processes, it is desirable to have a means of collecting accurate data on the impact of changes of the relevant vessel variables on the operation of different process vessel designs. This permits the identification of design changes which improve the efficiency of the processes carried out in the vessels.
What is desired is an alternative type of conductivity cell or probe which overcomes the disadvantages of wall probes currently used for characterizing the fluid flow within a process vessel and investigating the efficiency of fabrication processes conducted within the vessel.

Wafer gap conductivity cell for characterizing process vessels and semiconductor fabrication processes and method of use


A method for automatic recognition of human activity is provided and includes the steps of decomposing human activity into a plurality of fundamental component attributes needed to perform an activity and defining ontologies of fundamental component attributes from the plurality of the fundamental component attributes identified during the decomposing step for each of a plurality of different targeted activities. The method also includes the steps of converting a data stream captured during a performance of an activity performed by a human into a sequence of fundamental component attributes and classifying the performed activity as one of the plurality of different targeted activities based on a closest match of the sequence of fundamental component attributes obtained during the converting step to at least a part of one of the ontologies of fundamental component attributes defined during the defining step. A system for performing the method is also disclosed.

Automatic recognition of user activity can be used in numerous context-aware applications and technologies, such as, applications which provide recommendations, user profiling, health/wellness applications, and smart-home applications. For example, automatic recognition of user activity is useful with respect to providing context-based targeted advertising and activity-aware multimedia content recommendations such as shopping recommendations specifically targeted to users known to be involved in certain activities. Further examples include healthcare and activity monitoring for patients, elders, and children, life logging applications and automatic status updating of social networks, and technologies relating to proactive personal assistants which take into account current user activities and activity history of the user.
For purposes of automatically recognizing the activity of a user, the conventional approach is to collect and label a set of training data for each class of user activity that needs to be recognized and to match current activity sensor readings to readings expected for one of a plurality of pre-defined classes of targeted activities of interest. However, such an approach necessarily requires training data for each of the activities desired to be recognized and, if there is no training data for a particular activity, a proper match to such an activity cannot be made. Thus, an activity of interest which is considered "previously unseen" with respect to the acquisition of appropriate training data cannot be recognized.
Furthermore, labeled examples and training data are typically extremely time consuming and expensive to develop and/or acquire and require significant efforts of human annotators and/or experts for such data to be useful in predicting activity performed by a user based on sensor readings. Thus, the ability to expand successful recognition to additional activities of interest is difficult and requires significant investment.

System and method for activity recognition


A method for interferometric measurement comprises emitting waves onto a reference surface (1) and onto a measured object (2), which each reflects a part of the emitted waves, and receiving both the reflected parts of the waves by the same receiver (4). In the receiver the parts of the waves generate a representation of the measured object (2) in the form of an interferogram, from which the form of the measured object (2) is determined. The emitted waves comprise waves of three well-defined wavelengths xcexd1, xcexd2 and xcexd3, where xcexd1xe2x89xa0xcexd2xe2x89xa0xcexd3, which wavelengths are chosen to substantially satisfy the mutual relation xcexd1=(xcexd2.xcexd3)/(2.xcexd3xe2x88x92xcexd2) and generate an interferogram each in the receiver (4). An apparatus suited to implement the method comprises a light source (3) for emitting light, a reference surface for reflecting a first part of said light, and a receiver (4) which is arranged to receive the first part of the light and a second part of the light, reflected by a measured object (2). The light source is arranged to simultaneously emit light of the three above-mentioned well-defined wavelengths.

This invention relates to a method for interferometric measurement, which method comprises emitting waves onto a reference surface and onto a measured object which each reflect a part of the emitted waves, and receiving both the reflected parts of the waves by one and the same receiver, in which a representation of the measured object is generated from the reflected parts of the waves in the form of an interferogram, from which the form of the measured object is determined.
In addition to the method this invention also relates to an apparatus for interferometric measurement which includes a light source for emitting light, a reference surface for reflecting a first part of said light and a receiver which is arranged to receive the first part of the light and a second part of the light, reflected by an object, a representation of the measured object being generated in said receiver in the form of an interferogram from which the form of the measured object is determinable.
Optical interferometry is often used for non-contact measurement of the form of surfaces. For this purpose light which has been separated into two parts by the use of a prism, a semitransparent mirror or some other device is employed. One of these parts of the light illuminates and is reflected by a plane reference surface. The other part of the light illuminates and is reflected by the surface, the form of which is to be measured. The two reflected parts of the light are brought together to illuminate photographic film or some form of light recording electronics. The image thus produced is called an interferogram. From the interferogram the form of the surface can be determined. One example of an apparatus for Producing interferograms is shown schematically in FIG. 1.
In those cases where the light employed is monochromatic, i.e. all the light is of one and the same wavelength, the interferogram consists of light and dark regions. The lightest regions are generated where the two reflected parts of the light interfere constructively, i.e. where they are in phase. This is the case when the total distance (from the light source to the recording medium) is the same for the two parts of the light or when it differs by a whole number of wavelengths. The darkest regions are generated where the two reflected parts of the light interfere destructively, i.e. where they are in opposite phase. This is the case when the total distance (from the light source to the recording medium) for the two parts of the light differs by half a wavelength in addition to a whole number of wavelengths.
In those cases where the light employed is white, i.e. when the light is composed of light of different wavelengths, the interferogram consists of differently coloured regions. Light of one wavelength in the two reflected light components may interfere constructively in the same point where light of a different wavelength interferes destructively. In this way the spectral composition of the reflected light changes, i.e. the reflected light has a hue (dominant wavelength) as opposed to the case for the light source employed.
By analysing the changes in the interferogram, in intensity in monochromatic interferograms, in hue and possibly also intensity and saturation in interferograms recorded with white light sources, the position and form of the surface can be determined, although not always unambiguously.
When a monochromatic light source is employed, the surface can be translated in steps of half wavelengths (i.e. the total distance the light travels changes in steps of whole wavelengths) without changes in the interferogram. The determination of the position of the surface thus is ambiguous. Besides there is an ambiguity in the determination of the form of the surfacexe2x80x94an indentation in the surface may result in the same interferogram as a protuberance in the surface.
By employing a light source which emits white light, these ambiguities can be eliminated. However, the interval within which the form and position of the surface can be determined becomes very small, in the order of microns. Outside of this narrow interval so many interferences occur, both constructive and destructive, that the interferogram cannot be interpreted due to low colour saturation. In order to determine the position and form of a surface unambiguously, it is necessary to calibrate the instrumentation with the aid of a surface in an accurately known position and having an accurately known form (e.g. a spherical ball with known diameter, fastened in a fixed jig).
There are a number of important technical applications for measuring position and form within a very narrow interval. With a monochromatic light source it is then possible to eliminate ambiguities in the determination of the form of the surface by recording several (at least three) interferograms of the same surface with different displacements of the two light parts (e.g. a semitransparent mirror can be moved, see FIG. 2). This is called phase-stepping interferometry.
There are two kinds of phase-stepping interferometry. In the one kind, temporal phase-stepping, the interferograms are generated consecutively in time and it is thus assumed that the position and form of the surface is not changed during the time required to record all the necessary interferograms. In the other kind, usually called spatial phase-stepping, the different interferograms are generated simultaneously. This can be arranged in several different ways, e.g. by employing light with different polarisation angles. The instrumentation then is more extensive (e.g., three cameras must be used instead of one) but the form of the surface may change, which is necessary in many important applications.
In each of the references EP-A-506 296, EP-A-0 506 297 and the paper xe2x80x9cThree-color laser-diode interferometerxe2x80x9d, published in the journal Applied Optics, Vol. 30, No. 25, 1991, a method of extending the measurement range within which the structure of an object can be unambiguously determined is presented. This method is based on the employment of so-called synthetic wavelengths. Two monochromatic light rays with closely spaced wavelengths xcex1, xcex2, are generated by a laser diode and are directed onto the measured object. These light rays cooperate to generate a light ray with a so-called synthetic wavelength xcex912xe2x88x921=xcex1xe2x88x921xe2x88x92xcex2xe2x88x921, which is much longer than the individual wavelengths xcex1, xcex2 and therefore allows an unambiguous determination of larger structures of the measured object. In practice, however, two separate interferograms are detected, one for each of the wavelengths xcex1 and xcex2, from which information about the structure of the measured object can be extracted. These two interferograms are detected through temporal phase-stepping, and thus this method exhibits the aforementioned disadvantages. The two wavelengths xcex1 and xcex2 also must be very closely spaced, typically within 0.5 nm, and therefore the differences between the two measured interferograms are small which results in poor measurement accuracy. In practice therefore, in order to obtain an enhanced analysis of the structure of the measured object, one or several additional synthetic wavelengths, generated by combinations of light rays of different wavelengths and shorter than the first synthetic wavelength xcex912 are employed. The choice of synthetic wavelengths is determined by the wavelengths which are available from laser diodes of multimode type.
Against this background the object of the present invention is to overcome the disadvantages associated with the known technology and particularly with both the known phase-stepping solutions, since these solutions are otherwise very advantageous.
In accordance with the invention, this object is achieved by a method as described in the introduction by the emitted waves comprising waves of three well-defined wavelengths xcexd1, xcexd2 and xcexd3, where xcexd1xe2x89xa0xcexd2xe2x89xa0xcexd3, which wavelengths are chosen so that they substantially satisfy the mutual relation
xcexd1=(xcexd2xc2x7xcexd3)/(2xc2x7xcexd3xe2x88x92xcexd2)
and generate an interferogram each in the receiver.
In accordance with the method, phase-stepping is thus achieved by the emitted waves comprising waves the wavelengths of which are all different but adapted to each other. Since it is possible to generate these three wavelengths by simpler means than e.g. the aforementioned light with different polarisation angles and since the mutual relation is considerably simpler to handle, and additionally generates simultaneous interferograms, it is realised that the method in accordance with the invention overcomes the problems heretofore associated with phase-stepping. It is also realised that the invention is well applicable to other kinds of waves than the optic waves normally associated with phase-stepping. Finally it is realised that corresponding expressions for any of the other wavelengths, expressed in the two remaining wavelengths, can be given.
By well-defined wavelength for each one of the waves mentioned it is understood that the ratio between the spectral width (xcex94xcexd) and the mean wavelength (xcexd) for each wave is much smaller than 1. If one or several of the waves employed have too large spectral width compared to their mean wavelength, the corresponding interferogram will exhibit such large disturbances that the resulting measurement accuracy will be insufficient.
In accordance with the method of the invention, three interferograms (E1, E2, E3) are detected simultaneously. These three interferograms can mathematically be expressed as:   {                                          E            1                    =                      A            +                          B                                            xe2x80x83                                          cos                                            xe2x80x83                                                          (                                                      β                                                              xe2x80x83                                                            d                                                        v                    1                                                  )                                                                                E            2                    =                      A            +                          B                                            xe2x80x83                                          cos                                            xe2x80x83                                                          (                                                      β                                                              xe2x80x83                                                            d                                                        v                    2                                                  )                                                                                E            3                    =                      A            +                          B                                            xe2x80x83                                          cos                                            xe2x80x83                                                          (                                                      β                                                              xe2x80x83                                                            d                                                        v                    3                                                  )
where A and B are arbitrary constants, xcex2 is known and depends on the refractive index, and d is the sought quantity. The three wavelengths (xcexd1, xcexd2, xcexd3) are chosen to satisfy the equations:   {                                          1                          v              1                                =                                    Φ              0                        -                          Δ                                            xe2x80x83                                          Φ                                                                                1                          v              2                                =                      Φ            0                                                                    1                          v              3                                =                                    Φ              0                        +                          Δ                                            xe2x80x83                                          Φ
where "PHgr"0 and xcex94"PHgr" are arbitrary constants. The latter system of equations yields the interdependency xcexd1=(xcexd2xc2x7xcexd3)/(2xc2x7xcexd3xe2x88x92xcexd2) between the wavelengths. This particular choice of wavelengths is explained by the fact that by algebraic manipulation, linear combinations N and D in accordance with:
N=E1xe2x88x92E3=2B sin(xcex2d"PHgr"0)sin(xcex2dxcex94"PHgr")
D=2E2xe2x88x92E1xe2x88x92E3=2B cos(xcex2d"PHgr"0)(1xe2x88x92cos(xcex2dxcex94"PHgr"))
can be obtained.
The linear combinations N and D are quantities which can be measured from the simultaneously detected interferograms (E1, E2, E3), and in accordance with that stated above, xcex2, "PHgr"0 and xcex94"PHgr" are known quantities. From these linear combinations the equation:       tan              xe2x80x83                  (              β                          xe2x80x83                        d                          xe2x80x83                                  Φ          0                    )        =            N      D                  xe2x80x83            tan              xe2x80x83                  (              β                          xe2x80x83                        d                          xe2x80x83                        Δ                          xe2x80x83                        Φ                          /                        2            )
is obtained. This equation can be solved for the unknown quantity d with some suitable numerical method.
More concrete and applied to optical wavelengths, the receiver or the recording medium (colour film or colour video) in accordance with the invention thus simultaneously records three different interferograms, one for each wavelength. The difference in total distance travelled by the two parts of the light (the part of the light which is reflected by the reference surface and that part of the light which is reflected by the surface, the position and form of which is to be determined) expressed in number of wavelengths will then be different for different wavelengths and the phase displacement between the two components will therefore be different in the three different interferograms. Therefore a kind of phase-stepping interferomety has been achieved. The special relation between the different wavelengths which is required in accordance with the invention then makes it possible to determine the position and form of the surface from the three interferograms even when there are relatively large variations in the surface.
In the method according to the invention, either electromagnetic or mechanical waves are employed. The former are typically light waves in the visual spectrum and/or neighbouring intervals, i.e. the UV and IR intervals, since reliable sources and receivers for electro-magnetic waves in these intervals are available. According to a preferred embodiment, the light waves have the wavelengths xcexR, xcexG and xcexB, where R, G and B represent the hues red, green and blue since these hues are suited for receivers in the form of an ordinary photographic film or a video camera. The electromagnetic waves, however, can be in an arbitrary wavelength range, preferably in a range where reliable transmitters and receivers are available, such as the radio or X-ray range, if this is estimated to be advantageous on a specific measuring occasion.
Among mechanical waves in this context sound waves (acoustic waves) are the most important. The depth of penetration of these waves depends on their wavelength and they are particularly useful for non-transparent objects. In this context ultrasound waves are preferable since reliable transmitters and receivers are available.
Besides the method, the present invention relates to an apparatus of the type mentioned in the introduction, which is particularly intended for the application of the method when light is employed. In the apparatus in accordance with the invention, more particularly the light source is designed to simultaneously emit light of three well-defined wavelengths xcexd1, xcexd2 and xcexd3, where xcexd1xe2x89xa0xcexd2xe2x89xa0xcexd3, which wavelengths are chosen to substantially satisfy the mutual relation
xcexd1=(xcexd2xc2x7xcexd3)/(2xc2x7xcexd3xe2x88x92xcexd2)
and generate an interferogram each in the receiver.
A thus designed apparatus is very simple in its construction as compared to the aforementioned solutions for phase-stepping interferometry but still constitutes a well-functioning unit in practice.
This applies particularly if the light source comprises a lamp for emitting white light, a light splitter for splitting the light from the lamp into three parts and an interference filter for each such part, the interference filters being arranged to transmit light of one of the three well-defined wavelengths xcexd1, xcexd2 and xcexd3, one for each filter. In this embodiment, the invention thus makes it possible to determine the form of a surface also from interferograms which have been obtained by means of a light source emitting white light. The essential advantage of this is that no calibration, involving a known surface, is necessary. Besides the problem relating to colour saturation outside of a narrow interval is elimlnated and the form of the surface may therefore vary within a larger interval than before.

Method and apparatus for interferometric measurement


An improved multiple bus system for a multiprocessor computer system is disclosed for a computer system having a multiple level cache memory structure. The system includes one or more logical busses each including two or more physical busses for coupling multiple processors to a memory unit. Each logical bus is coupled to a bus switching unit which in turn couples all of the processors in the multiprocessor system to a memory unit over the physical busses comprising the logical bus. The system further manages near end signal reception problems caused by multiple processors electrically interconnected over such a bus system.

The bus structure in a multiprocessor computer system has a significant impact on the overall performance, the functionality and the granularity of the system. One of the most important key characteristics for an efficient bus is its bandwidth which describes the ability of the bus to match with the processors speed and a variable number of processors. It depends on the bus width, the efficient usage of the bus by the bus protocol and the bus cycle time.
The bus width is limited by physical constraints of the package as there are chip pads, module pins or wireability of cards and boards. In prior art bus systems therefore either one large or a set of smaller busses is constructed.
In another prior art approaches a smart bus protocol allows bus interleaving between processors to fill the time gap on the bus caused by the access time of the addressed memory bank. "Bus interleaving" is a known method to use wait cycles on a bus to issue a command to other memory banks. It allows several memory banks per bus to be operated simultaneously in order to increase the bus- and memory bandwidth.
The bus cycle time is the main contributor to the bus bandwidth. An efficient bus structure has to provide excellent electrical characteristics to match the processor and the bus cycle time as close as possible. For example, a simple structure which connects processors like a laundry line limits the cycle time and the number of processors by its poor electrical characteristics. In contrast, a much more complex structure provides point to point busses between each processor and a central switch unit. One or several memory banks are connected to that unit. That structure allows a short bus cycle, but requires an extensive wiring. For the packaging, a central switch unit also requires a very high pin count, since all busses are routed to the switch.
In addition, in prior art systems the performance of bus structures is improved by concepts for bus arbitration which may either be implemented as a distributed or a central arbitration function. The central arbitration concept is based on an additional hardware component, a controller, like a central bus switch. It receives all bus requests, performs the arbitration and delivers the grant to the requesting unit in the next cycle.
The distributed approach requires more wiring, because all request lines have to be wired to all bus participants. But its advantage is that the arbitration can be fulfilled within one cycle, since only one off-chip network is in the path, compared with the a central arbitration. The complete path consists of an off-chip network, i.e. the request lines, and the arbitration logic. If this limits the bus cycle time, then a two cycle central bus arbitration will become the preferred solution.
A further key characteristic for an efficient bus structure is the provisions which provides for data consistency assurance in a multiple cache processor structure. A known simple concept is the so called bus snooping. Hereby each processor monitors the bus operations of all other processors to keep track on the status of its cache lines. The status may be "modified", "exclusive", "shared" or "invalid". The required actions are a line invalidation or a cast-out of modified data with or without updating the memory. A cast-out of modified data means that a PU is no longer the exclusive owner of the line. All those operations are initiated and controlled by the individual processors.
But this simple concept has its limits, if there is more than one bus in the structure, as in a system with a central switch. Hereby data consistency has to be controlled by the central switch. It keeps copies of all cache directories of the processors, as well as the status of each line. The central switch monitors the status of the cache lines, initiates cast-outs from processors, if required, and issues the necessary memory commands and the data transfer. Advantageous are the short cycle time and the high bus/memory bandwidth. But a disadvantage of this approach is that it requires a design effort comparable to a complete processor, including a cache. Therefore, this costly concept can be only implemented in high end mainframe designs.
Such a central arbitration concept is disclosed in IBM Technical Disclosure Bulletin, vol. 35, no. 6, November 1992 (FIG. 2) employing a central crossbar switch. Herein, memory requests are transferred via a processor bus, and data via the crossbar switch to a memory unit. This dividing up concept allows a central memory control for an interleaving access to a number of memory banks.
Another approach for central arbitration is given in U.S. Pat. No. 5,355,455 to the present assignee which concerns with the problem of deadlocks in computer systems with several busses being connected by a bus adapter. The bus adapter divides the common bus system into two partial busses wherein the first part contains a processing unit and a memory unit, and the second part contains several I/O control units (FIG. 1 of that document). The underlying problem of that invention is concerned with computer systems having two data busses, where a bus unit of the first bus wants to communicate with a bus unit of the second bus, while a bus unit of the second bus wants to communicate with another bus unit of the first bus, normally leading to a deadlock situation. This problem originates in a bottleneck situation on grounds of the only one bus adapter and is particularly solved by introducing a BUS SUSPEND control signal.
An example for a distributed arbitration approach is disclosed in U.S. Pat. No. 5,093,826 assigned to Siemens Aktiengesellschaft, Germany, which is related to a redundant bus system which is split into two arbitrary halves which are connected to corresponding halves of a redundant main memory. Hereby identical information are stored in the two different memories. According to the teaching of that patent, in a special operating time, individual processors, one bus system half, and some of the memory sections are split off and interconnected to form an independent special-purpose computer.
European Patent Application No. 0 557 651 concerns with a multiprocessor system which allows an efficient interleaving on a memory bus. This concept allows multiple access of bus participants to the memory since the memory is logically divided into at least two memory banks.
Further, in German Patent GE-PS 3 708 887, a parallel bus structure is disclosed, whereby the bus is divided into sections by means of registers being inserted between those sections. In each bus section at a given time data are transferred independently of each other, or data are pipelined. Due to subdividing the data bus in individual bus sections with a physical length of typically centimeter, the signal transmission time is strongly reduced. Therefore higher cycle times and transfer rates are achievable.

Logical bus structure including plural physical busses for a multiprocessor system with a multi-level cache memory structure

International Business Machines Corporation


The invention provides N-acyl-N-phenyltetrahydrophthalamic acid derivatives represented by the general formula [I], methods of producing the same, and herbicides containing the same as the effective components, ##STR1## wherein X and Y each individually represent hydrogen atoms or halogen atoms, R.sup.1 represents a hydrogen atom, a halogen atom, a lower alkoxy group, a lower alkenyloxy group, a lower alkynyloxy group, a lower alkoxyalkoxy group or a lower alkoxycarbonylalkoxy group, R.sup.2 represents a lower alkyl group, a halogenated lower alkyl group, or a substituted or unsubstituted phenyl group, and R.sup.3 represents a lower alkoxy group, a lower alkenyloxy group, a lower alkynyloxy group, a lower alkoxyalkoxy group, a benzyloxy group or a lower alkoxycarbonylalkoxy group. The herbicides which are very useful can be widely applied to upland, paddy field, orchard, turf, forest, non-crop land, etc, and are not harmful to crops.

Hitherto, herbicidal activity of tetrahydrophthalamic acid derivatives is well known. For example, N-(4'-chlorophenyl)-3,4,5,6-tetrahydrophthalamic acid methyl ester is known, as is disclosed in JP-A (Patent) 48-44425.
However, the conventional tetrahydrophthalamic acid derivatives are not necessarily sufficient in herbicidal activity, or are substantially limited in herbicidal spectrum against weeds. Furthermore, these derivatives are insufficient in selectivity between crops and weeds, thereby inducing problems of safety for crops.
It is an object of the present invention to solve the aforementioned problems, and to provide a novel compounds which are excellent in herbicidal activity but not harmful to crops, methods of producing the same, and herbicides containing the same as the effective components.

N-acyl-N-phenyltetrahydrophthalamic acid derivatives, methods of producing same, and herbicides containing same as effective components


An improved data access arrangement device for use in full-duplex two-wire communication systems having a transmission impedance characteristic. The DAA includes a transmit amplifier and a receive amplifier adapted for connection to a two-wire line, a codec connected to the transmit amplifier for generating a transmit signal, a summation device connected to the receive amplifier, an echo cancellation path including a variable gain amplifier, where the path extends between the codec and the summation device, and wherein the variable gain amplifier is adjusted in accordance with the transmission impedance characteristic. The variable gain amplifier may include a gain register that is programmed by a microprocessor, or may have the gain set by user-configurable switches. The summation device is preferably an operational amplifier.

Past implementations of hybrids used to accomplish four-wire to two-wire conversion employ a transmission signal cancellation path to duplicate and cancel the portion of the outgoing transmission signal that is erroneously picked up by the receive amplifier. A hybrid used in a typical solid-state Data Access Arrangement (DAA) device will employ a gain stage that serves as the transmission signal cancellation path.
Telephone lines present a wide range of characteristic impedances. The characteristic impedance varies with frequency on a particular telephone line, and each two-wire subscriber line, or telephone line, will present a different characteristic.
Hybrids in present DAA devices use a fixed gain stage for cancellation that is not responsive to changes in the telephone line impedance. Such a fixed gain stage does not provide frequency dependent impedance matching. The DAA is designed to perform a coarse echo cancellation by providing a hybrid that is not precisely balanced. The prior art DAA devices do not provide for the connection of external impedance matching devices.
In view of recent telecommunication techniques that utilize a larger portion of the available bandwidth such as that specified by ITU-T recommendation V.90, it would be advantageous to provide a transmission signal cancellation path in a DAA device that is more flexible and responsive to varying telephone line conditions, and which is able to better model the telephone line impedance to provide better echo cancellation, especially at the band edges.

Filtered transmit cancellation in a full-duplex modem data access arrangement (DAA)


A system and method for bad frame indication of a speech frame includes estimating a signal-to-noise ratio (SNR) and checking a cyclic redundancy code (CRC) value of the speech frame. When the speech frame fails CRC error detection or the SNR is below a pre-specified value, a bad frame indication (BFI) flag is set. When the speech frame passes CRC error detection and the SNR is above the pre-specified value, a receive signal quality metric of the speech frame is checked against a high threshold and, if need be, a low threshold. The BFI flag and the receive signal quality metric for the previous speech frame is checked when the current receive signal quality metric is between the high and low thresholds. The BFI flag is set according to the value of the SNR, the CRC value, the current and previous receive signal quality metrics, and the previous BFI flag.

The present invention generally relates to wireless digital communication using voice encoding and, more particularly, to a system and method for detecting bad data frames in reception of voice transmissions.
Global System for Mobile communications (GSM) is a mobile telecommunication system with GSM networks operational in several countries around the world. The GSM system operating at 900 mega-Hertz (MHz), and its sibling systems operating at 1.8 giga-Hertz (GHz) (called DCS1800) and 1.9 GHz (called GSM1900 or PCS1900, and operating in North America), are specified according to a GSM standard published by the European Telecommunication Standards Institute (ETSI). A basic telecommunications service supported by GSM is telephony. As with other types of communications, speech is digitally encoded and transmitted through the GSM network as a digital stream.
FIG. 1 shows the general architecture of a generic GSM network 100. GSM network 100 is composed of several functional entities, whose functions and interfaces are specified, for example, according to standards published by ETSI. GSM network 100 can be divided into three subsystems. The mobile station or subsystem 102 is carried by the subscriber, for example, a person using the mobile station 102 as a telephone. A base station subsystem (BSS) 104 controls a radio link 106 with the mobile station 102. A network subsystem 108, the main part of which is a mobile services switching center (MSC) 110, performs the switching of calls between mobile users—such as a person using the mobile station 102, and between mobile users and fixed network users. The MSC 110 also handles the mobility management operations. The mobile station 102 and the base station subsystem 104 communicate across a Um interface 112, also known as an air interface or radio channel 112. The base station subsystem 104 communicates with the mobile services switching center 110 across an A interface 114.
The mobile station 102 includes mobile equipment 116 (the terminal) and a smart card called the subscriber identity module (SIM) 118. The SIM 118 provides personal mobility so that the user can have access to subscribed services irrespective of a specific terminal, i.e. mobile equipment 116. By inserting the SIM 118 card into another GSM terminal (not shown), the user is able to receive calls at that terminal, make calls from that terminal, and receive other subscribed services.
The base station subsystem 104 includes two parts, a base transceiver station (BTS) 120 and a base station controller (BSC) 122. One or more base transceiver stations 120 communicate with a base station controller 122 across a standardized Abis interface 124, allowing (as in the rest of the system) operation between components made by different suppliers. The base transceiver station 120 houses the radio transceivers that define a cell and handles the radio-link protocols with the mobile stations, for example, mobile station 102. In a large urban area, there will potentially be a large number of base transceiver stations 120 deployed. A base station controller 122 manages the radio resources for one or more base transceiver stations 120. The base station controller 122 handles radio-channel setup, frequency hopping, and handovers, for example. The base station controller 122 is the connection between the mobile station 102 and the MSC 110.
The central component of network subsystem 108 is the MSC 110. The MSC 110 acts like a normal switching node of a public switched telephone network (PSTN) or an integrated services digital network (ISDN), and additionally provides functionality needed to handle a mobile subscriber, such as registration, authentication, location updating, handovers, and call routing to a roaming subscriber. These services are provided in conjunction with several functional entities, which together form the network subsystem 108. The MSC 110 provides connection to the fixed networks 126 (such as the PSTN, ISDN, packet switched public data networks (PSPDN), and circuit switched public data networks (CSPDN)). Signaling between functional entities in the network subsystem 108—such as MSC 110 and a home location register (HLR) 128—uses Signaling System Number 7 (SS7), used for trunk signaling in ISDN and widely used in current public networks. For example, the HLR 128 and a visitor location register (VLR) 130, together with MSC 110, provide the call-routing and roaming capabilities of GSM. An equipment identity register (EIR) 132 is a database that contains a list of all valid mobile equipment on the network. An authentication center (AuC) 134 is a protected database that stores a copy of the secret key stored in each subscriber's SIM 118 card, which is used for authentication and encryption over a radio channel 112.
GSM uses a combination of Time-Division Multiple Access (TDMA) and Frequency-Division Multiple Access (FDMA) to share the limited bandwidth of the radio channel 112 among multiple users, i.e., for communication between multiple mobile stations 102 and a base transceiver station 120. FDMA employed by GSM involves the division by frequency of the maximum 25 mega-Hertz (MHz) bandwidth of the radio channel 112 into 124 carrier frequencies spaced 200 kilo-Hertz (kHz) apart. One or more carrier frequencies are assigned to each base transceiver station 120. Each of these carrier frequencies is then divided in time, using a TDMA scheme such as a TDMA scheme 200 shown in FIG. 2.
FIG. 2 illustrates the timing structure of exemplary TDMA scheme 200 used by GSM. The fundamental unit of time in the TDMA scheme 200 is called a burst period (BP)—illustrated by burst periods 202 in FIG. 2. A burst period 202 lasts 15/26 milliseconds (ms)—or approximately 0.577 ms. Eight burst periods 202 are grouped into a TDMA frame 204 ( 120/26 ms, or approx. 4.615 ms). The TDMA frame 204 forms the basic unit for the definition of logical channels. For example, a channel may be defined as one of the burst periods 202 per TDMA frame 204. Channels are defined by the number and position of their corresponding burst periods 202.
A traffic channel (TCH) 206 is used to carry speech and data traffic. The traffic channels 206 are defined using a 26-frame multi-frame 208, which is a group of 26 TDMA frames 204. The length of a 26-frame multi-frame 208 is 120 ms, which is how the length of a burst period 202 is defined (120 ms divided by 26 TDMA frames divided by 8 burst periods per frame). Out of the 26 TDMA frames 204, twenty-four of them are used for traffic channels 206, one is used for a slow associated control channel (SACCH) 210, and one is currently an unused TDMA frame 212, as seen in FIG. 2. Traffic channels 206 for the uplink and downlink are separated in time by 3 burst periods, so that the mobile station 102 does not have to transmit and receive simultaneously, thus simplifying the electronics.
There are four different types of bursts, i.e., data occupying a burst period 202, that are used for transmission in GSM. A normal burst—such as burst 214—is used to carry data and most signaling. The normal burst 214 has a total length of 156.25 bits, made up of two 57 bit information blocks, or data bits 216, a 26 bit training sequence 218 used for equalization, one stealing bit 220 for each information block, i.e., data bits 216,—used for fast associated control channel (FACCH), three tail bits 222 at each end, and an 8.25 bit guard sequence 224, as shown in FIG. 2. The 156.25 bits of normal burst 214 are transmitted in 0.577 ms, giving a gross bit rate of 270.833 kbps.
GSM is a digital system so that speech, which is inherently analog, has to be digitized. The voice encoder/decoder (also referred to as "codec" or "vocoder") of GSM employs a digitization technique called regular pulse excited—linear predictive coder (RPE-LPC) with a long term predictor loop. Basically, information from previous speech samples, which does not change very quickly, is used to predict the current speech sample. Speech is divided into 20 millisecond samples, each of which is encoded by the vocoder as 260 bits, giving a total bit rate of 13 kbps, called Full-Rate speech coding.
Because of natural and man-made electromagnetic interference, the encoded speech or data signal transmitted over the air interface, radio channel 112, must be protected from errors. GSM uses convolutional encoding and block interleaving to achieve this protection. The algorithms used differ for speech and for data. For speech, the vocoder produces a 260 bit block, called a speech frame, for every 20 ms speech sample. Some bits of this 260 bit block, or speech frame, are more important for perceived speech quality than others. The bits are thus divided into three classes:                Class Ia—50 bits—most sensitive to bit errors;        Class Ib—132 bits—moderately sensitive to bit errors;        Class II—78 bits—least sensitive to bit errors.
Class Ia bits have a 3 bit cyclic redundancy code (CRC) added for error detection. If an error is detected, the speech frame containing the 260 bit block is judged too damaged to be comprehensible, referred to as a "bad speech frame" or "bad frame", and is discarded. The discarded speech frame is replaced by an attenuated version of the previous correctly received speech frame. The 53 Class Ia bits, together with the 132 Class Ib bits and a 4 bit tail sequence (a total of 189 bits), are input into a ½ rate convolutional encoder of constraint length 4. Each input bit is encoded as two output bits, based on a combination of the previous 4 input bits. The convolutional encoder thus outputs 378 bits, to which are added the 78 remaining Class II bits, which are unprotected. Thus every 20 ms speech sample is encoded as 456 bits, giving a bit rate of 22.8 kbps.
To further protect against the burst errors common to the air interface, radio channel 112, each speech sample is interleaved. The 456 bits output by the convolutional encoder are divided into 8 blocks of 57 bits, and these blocks are transmitted in eight consecutive time-slot bursts 214, i.e., burst periods 202. Since each time-slot burst 214 can carry two 57-bit information blocks of data bits 216, each burst 214 carries traffic from two different speech samples.
Discontinuous transmission (DTX) is a method that takes advantage of the fact that a person speaks less than 40 percent of the time in normal conversation, by turning the transmitter off during silence periods, thereby conserving power. The most important component of DTX is voice activity detection. DTX voice activity detection distinguishes between voice and noise inputs despite the presence of background noise. If a voice signal is misinterpreted as noise, the transmitter is turned off and a very annoying effect called clipping is heard at the receiving end. If, on the other hand, noise is misinterpreted as a voice signal too often, the efficiency of DTX is dramatically decreased. In addition, when the transmitter is turned off, there is total silence heard at the receiving end, due to the digital nature of GSM. To assure the receiver that the connection is not dead, comfort noise is created at the receiving end by matching the characteristics of the transmitting end's background noise.
The GSM standard published by ETSI, for example, European Standard Telecommunication Series (ESTS) 11.10 Release 1999, at section 14.1 and, in particular, at sections 126.96.36.199 and 18.104.22.168, requires a mobile station, for example, mobile station 102, to meet a certain level of performance in DTX mode with regard to bad speech frames that are passed to the vocoder. If the phone, i.e., mobile station 102, provides multiple types of service, for example, GSM and PCS1900 in the same phone, the mobile station 102 is required to meet the performance criteria at each operational frequency, for example, the 900 MHz of GSM and the 1.9 GHz of PCS1900. The GSM standard refers to the performance that is tested as bad frame indication (BFI), and a bad speech frame that is passed to the vocoder is referred to as an "undetected bad frame". The GSM standard requires, for example, that less than 0.041% of frames passed to the vocoder be undetected bad frames, which corresponds to less than one undetected bad frame per 60 seconds. For example, in DTX mode, frames that contain silence or only background noise may result in bad speech frames that should be prevented from being passed to the vocoder.
In a full rate speech traffic channel (TCH/F or TCH/FS)—such as traffic channel 206—the fact that only 3 bits are used for the CRC error detection means that there is a significant probability that the CRC error detection will pass a bad frame to the vocoder as a correctly received speech frame, i.e., a good frame. For example, when the input to mobile station 102 is purely white noise or randomly modulated data, each bit of the 3-bit CRC has a 50—50 chance, or probability ½, of correctly matching the random data so that the CRC will pass ½3=12.5% of the random data when none should pass. Because of various technical considerations, for example, that half of the frames may be interpreted as FACCH frames that fail the 40-bit CRC for FACCH, it may be assumed that only 6.25% of the random data will pass CRC, which is unacceptable when compared to the 0.041% required by the GSM standard.
As can be seen, there is a need for bad frame indication for GSM mobile stations that overcomes the limitations of the 3-bit CRC error detection for speech frames by detecting bad frames that have passed the CRC. There is also a need for bad frame indication for GSM mobile stations that prevents passing to the vocoder those frames for which there is no input signal but still pass CRC. Moreover, there is a need for bad frame indication that fails a negligible number of good speech frames when a good signal is being received.

Bad frame indicator for radio-telephone receivers in GSM mobile systems


A communication system is disclosed, in which a mobile telephone communicates user data substantially simultaneously via a first base station and a second base station of the communication system. The mobile telephone detects a problem in communications with the second base station and transmits, to the first base station on detection of a problem in communications with said second base station, an indication of the detected problem in communications with the second base station.

In a cellular communications network, user equipment (UE) (such as mobile telephones, mobile devices, mobile terminals, etc.) can communicate with other user equipment and/or remote servers via base stations. LTE systems include an Evolved Universal Terrestrial Radio Access Network (E-UTRAN) and an Evolved Packet Core (EPC) network (or simply 'core network'). The E-UTRAN includes a number of base stations ('eNBs') for providing both user-plane (e.g. Packet Data Convergence Protocol (PDCP), Radio Link Control (RLC), Medium Access Control (MAC) and PHYsical (PHY) layers) and control-plane (e.g. Radio Resource Control (RRC)) protocol terminations towards the UE.
Conventionally, a mobile telephone is configured to communicate via one base station (using an associated radio link). The mobile telephone can determine (as specified in 3GPP TS 36.331 V11.5.0 section 184.108.40.206) that there is a failure of the radio link between the mobile telephone and a serving base station, by monitoring various parameters associated with communications via that base station. For example, the mobile telephone may monitor for and detect that at least one of the following events has occurred (with respect to a cell of a base station):                RLC retransmission failure;        Random Access Channel (RACH) failure;        PHY problem recovery failure (upon expiry of an associated T310 timer);
In each detected failure situation, the mobile telephone tries to re-establish the (RRC) connection with that base station or another base station (e.g. based on signal quality measurements followed by a cell re-selection procedure).
Further, there may be other problems (that may or may not be indicative of a radio link failure) associated with a base station (e.g. a problem associated with a cell/radio link thereof). Such problems associated with a communication bearer include, for example:                a Scheduling Request (SR) failure (as specified in 3GPP TS 36.321 V11.3.0 section 5.4.4); and        an expiry of an associated Time Alignment Timer (TAT) for a particular Timing Advance Group (TAG) that the mobile telephone 3 belongs to (e.g. the last TAG, a Primary TAG, etc.) as specified in 3GPP TS 36.321 section 5.2.
When the mobile telephone experiences an SR failure and/or a TAT expiry (and/or the like) associated with a communication bearer, it performs a Contention Based Random Access (CBRA) procedure (over an associated RACH) with the base station serving that communication bearer. Once the (RRC) connection with the base station has been re-established (or the CBRA procedure resulted in restoring the connection with that base station), the mobile telephone can be handed over to a different cell (of that base station or a different base station), if appropriate.
However, in extreme cases, e.g. whilst the mobile telephone is carrying out a connection (re-)establishment with a suitable base station, the mobile telephone might not be able to send/receive any data without interruption/delay.
Recent developments in communication networks have seen increased deployment of so called 'small' cells operated by Low Power Nodes (LPNs), such as pico eNBs, femto eNBs, home eNBs (HeNBs) or the like, which cells have a smaller coverage area than existing macro cells operated by a higher power (regular) macro base station. Networks comprising a number of different cell types, for example a network comprising a macro cell and a femto cell, are referred to as Heterogeneous Networks, or HetNets. In the following description the term base station is used to refer to any such macro base station or LPN.
In a study on small cell enhancements for E-UTRA and E-UTRAN (3GPP technical report (TR) no. 36.842 V0.2.0, the contents of which are incorporated herein by reference), a so-called 'dual connectivity' functionality was introduced to improve, for example, the coverage of high data rates for user equipment, temporary network deployment, cell edge throughput and/or to increase system throughput. The dual connectivity feature established techniques for compatible mobile telephones (and other user equipment) to communicate with multiple network points, substantially simultaneously. Specifically, this 'dual connectivity' functionality refers to an operation mode where a given mobile telephone (operating in RRC_CONNECTED mode) consumes radio resources provided by at least two different network points (e.g. two or more base stations). Typically, one of the network points involved in the dual connectivity functionality is a macro base station and the other network point (or a plurality of network points) comprises a low power node (or plurality of low power nodes).
Each network point involved in the provision of dual connectivity for a mobile telephone may assume a different role. One of the network points may be referred to as a master base station (MeNB) and each one of the other network points may be referred to as a secondary base station (SeNB). Typically, the various secondary base stations involved in the provision of dual connectivity are coupled via a so-called non-ideal backhaul. Here, the term 'non-ideal backhaul' may refer to a backhaul between the cell and the core network comprising a communication link provided between a MeNB and the SeNB. Further, in a dual connectivity scenario, one of the base stations (the MeNB) routes control plane signaling to the core network (e.g. to a mobility management entity (MME) in the core network) via an associated interface (e.g. The S1-MME interface), regardless of whether or not the other base station is also connected to the core network for user plane communication (e.g. to a serving gateway via an S1-U interface). Therefore, from the core network/MME perspective, the MeNB acts as a mobility anchor point.
The MeNB/SeNB roles do not necessarily depend on each base station's capabilities/type (e.g. power class) and may be different for different mobile telephones (even when using the same base stations).
In accordance with the dual connectivity functionality, a mapping between the mobile telephone's radio (communication) bearer(s) and the base stations may be realised as follows:                Radio Bearer served by the MeNB only (MeNB-specific bearer);        Radio Bearer served by the SeNB only (SeNB-specific bearer); and        Radio Bearer served by MeNB and SeNB (split bearer).
However, in a dual connectivity scenario difficulties arise in abnormal situations affecting communication with one of the base stations providing the dual connectivity but not the other base station(s) providing the dual connectivity. Such abnormal situations may arise, for example, in the case of a sudden/complete connection loss, unexpected interference, failure to successfully transmit a packet after a predetermined number of retransmission attempts, failure to receive a response after a predetermined number of preamble transmissions/scheduling requests, and/or the like.


An image forming apparatus includes an image forming body for carrying thereon a toner image, and a belt-shaped intermediate transfer body for carrying thereon the toner image transferred from the image forming body. A first transfer device is provided for transferring another toner image carried by the image forming body onto an obverse side of a recording sheet conveyed by the intermediate transfer body, and a second transfer device is provided for transferring the toner image carried on the intermediate transfer body onto a reverse side of the recording sheet. In addition, a fixing device is provided for fixing the toner images transferred on both sides of the recording sheet which is separated from the intermediate transfer body, and a conveyor portion having spurred wheels is provided between the intermediate transfer body and the fixing device for conveying the transfer member to the fixing device. The apparatus has a structure including two frames which can be opened. When the frames are closed, the image forming body is set to a first position adjacent to and facing the intermediate transfer body and the second transfer device is set to a second position adjacent to the intermediate transfer body and the conveyor portion, and when the frames are opened, the image forming body is apart from the first position and the second transfer device is apart from the second position.

The present invention relates to an image forming apparatus of an electrophotographic system such as a copying machine, a printer and a facsimile telegraph, wherein a charging means, an imagewise exposure means and a developing means are arranged around an image forming body, and a toner image formed on an image carrier is transferred onto a transfer member (hereinafter referred to as a recording sheet) and fixed thereon.
For two-sided copying in the past, an image for one side formed on an image forming body is first transferred onto a recording sheet and fixed thereon, and the recording sheet is stored temporarily in reversing/sheet-feeding unit, and then is fed from the reversing/sheet-feeding unit in a synchronization with an image formed again on the image forming body so that the image for the other side is transferred onto the recording sheet and fixed thereon.
In the two-sided copying apparatus, a recording sheet is fed to a reversing/sheet-feeding unit and is passed through a fixing unit twice. Therefore, reliability of conveyance of the recording sheet has been low, resulting in a cause for jamming. In contrast to this, Japanese TOKKOSHO Nos. 49-37538 and 54-28740 and TOKKAIHEI Nos. 1-44457 and 4-214576 disclose a technology wherein toner images are formed on both sides of a recording sheet and then are fixed collectively on the recording sheet. In each of TOKKAIHEI Nos. 1-44457 and 4-214576, in particular, there is disclosed a method wherein a plurality of toner image receiving bodies each being composed of an image forming body, a charging means, an imagewise exposure means and a developing means are arranged in parallel on a toner image receiving body so that a two-sided copy of color images may be formed.
In the two-sided color image forming proposed by TOKKAIHEI Nos. 1-44457 and 4-214576, however, image deteriorations such as doubling, toner scattering and frictional damage tend to be caused because color toner images each being different in color are superimposed on an intermediate transfer body, although conveyance of a recording sheet is improved.
In contrast to this, the inventors of the present invention have studied a two-sided image forming apparatus wherein toner images formed on an image forming body are collectively transferred onto a belt-shaped intermediate transfer body (toner image receiving body) temporarily, then toner images are formed on the image forming body again, and the toner images on the toner image receiving body and the toner images formed again on the image forming body are transferred respectively onto both sides of a recording sheet (a transfer member). However, it is not easy to clear jamming of the recording sheet in the sheet feeding path between the image forming body and the belt-shaped toner image receiving body. For easy jam clearance, therefore, the inventors have studied the structure wherein an apparatus is divided into an upper shell and a lower shell with a sheet-feeding path between, in which, however, a transfer-separating means provided to face a toner image receiving body obstructs jam clearance at the edge on the part of a fixing means, causing a problem that the transfer-separating means is damaged, and, in particular, a discharging electrode provided on the transfer-separating means is damaged.
The inventors have also studied that a conveyance section with spurred wheels which is provided between a toner image receiving body and a fixing means so that a recording sheet having on its both sides toner images formed may by conveyed without suffering damage of the toner images from the toner image receiving body to the fixing means. However, there still is a problem in that the spurred wheels may be damaged in the course of jam clearance or in that the spurred wheels can hurt human hands.

Image forming apparatus which includes spurred wheels provided on a conveyance section in a manner which makes jam clearance easy and which avoids damage to both the apparatus and an operator's hands