A flow path splitter duct is provided. The flow path splitter duct includes a main hub, a first outlet hub and a second outlet hub. The main hub has a plurality of inlet ports each being separated by at least one wall. The first outlet hub has a plurality of first duct outlet ports, each of the first duct outlet ports are in fluid communication with only one of the corresponding plurality of inlet ports. The second outlet hub has a plurality of second duct outlet ports, each of the second duct outlet ports are in fluid communication with only one of the corresponding plurality of inlet ports, wherein engine exhaust gas that enters one of the plurality of inlet ports is simultaneously diverted to only one of the first duct outlet ports and to only one of the second duct outlet ports. A vertical takeoff and landing aircraft is also provided that includes the flow path splitter duct. A method of using the same is also provided.

In order to have vertical takeoff and landing capability of a helicopter and to have forward flight speed ability of another aircraft, different styles of vertical takeoff and landing (VTOL) aircraft are being introduced and becoming more abundant. One aircraft is the canard rotor/wing design. The canard rotor/wing (CRW) design typically includes a single wing centrally located or two offset wings located on an aircraft fuselage that may be operated in a helicopter mode and in a fixed wing mode. Each wing includes two symmetrical blades that operate irrespective of flow direction. In helicopter mode the wing of the CRW spins the rotor. In fixed wing mode the wing of the CRW is locked for fixed flight mode.
In helicopter mode, the CRW uses ducted engine exhaust gas that flows through a passage way and into nozzles located on both blades of the wing to spin the rotor head. The engine exhaust gas passes through the main conduit, passes up the main rotor mast, proportionally through the gas splitter duct and out through the each rotor hub and blade to spin the rotor head. Two or more engines may be utilized on the CRW when the aircraft increases in size or when there is a desire to have additional engines. While the ducted passageways may provide for the increase in engine exhaust gas produced by the multiple engines, there becomes a loss of efficiency through the nozzles and a potential loss of engine control when the CRW experiences a loss of engine or engine out. The loss of efficiency and engine control situation may also occur when less than all of the engines are operating while the CRW is in helicopter mode. Generally, this is known as the "1-engine out" situation.
It is therefore, desirable to provide a VTOL aircraft having increased performance and engine control should the aircraft experiences the "1-engine out" situation.


The present invention relates to the use of peracylated N-acyl-mannosamine derivatives for the preparation of a medicament for stimulating neurite growth.

Sialic acids are carbohydrates which form a family of about 40 naturally occurring derivatives of neuraminic acid and which all except one are N-acylated (Schauer et al., 1995; Varki, 1992). They are distinguished from another by N and/or O substituents. N substituents are primarily acetyl and glycolyl groups. O substituents are, among others, acetyl, lactoyl, methyl, sulfate and phosphate groups. The most abundant representative of sialic acids is N-acetylneuraminic acid (NeuNAc), which is the precursor of all other sialic acids. Sialic acids are the terminal monosaccharides of complex N-glycans and many O-glycanes of glycoproteins as well as gangliosides.
By different modifications and binding types, the neuraminic acids contribute to the structural variety of glycoconjugates and have a great influence on numerous biological processes.
While sialinic acids play an important role in various biological processes, until recently, nothing was known about the importance of their N-acetyl or N-glycolyl side chain in these processes. The physiological precursor of all natural sialinic acids is N-acetylmannosamine. By the application of non-physiological N-acyl-mannosamines or glucosamines whose side chain is extended by one or more methylene groups, the corresponding neuraminic acids are biosynthesized (Grunholz et. al., 1981; Kayser et al. 1992).
A precursor such as N-propanoylmannosamine (ManNProp) is metabolized into N-propanoylneuraminates and subsequently, as N-propanoyineuraminic acid (NeuNProp), it is incorporated into the membrane proteins of the cells as well as into the serum glycoproteins (gangliosides) (Kayser et al., 1992).
Cell culture experiments have shown that biological processes such as viral infections and cell proliferation are permanently influenced by thus modified neuraminic acids.
DE 197 38 484 discloses the use of N-propanoylmannosamine, N-isopropanoyl-mannosamine and/or N-cyclopropanoylmannosamine (i.e., more correctly, N-cyclopropylcarbonylmannosamine) for the preparation of a medicament for myelinization and remyelinization. The capability of the above mentioned mannosamine derivatives of effecting myelinization and remyelinization is based on their property of being stimulators of oligodendrocytes.
Further, WO 00/07602 describes that particular N-acylmannosamines (such as N-acetyl-, N-propanoyl-, N-glycolyl-, N-formylmannosamine) are suitable for the modulation of neuronal growth or for the enhancement or inhibition of neurite growth. However, these compounds have the drawback that their effectiveness is rather low. On the other hand, WO 00/07602 also discloses O-acylated derivatives of the above mentioned compounds; in particular, N-glycolylmannosamine pentaacetate is mentioned. However, all the glycolylmannosamine derivatives have the drawback of being antigenic.
Surprisingly, it has been found that special N- and O-acylated mannosamine compounds can stimulate neurite growth significantly better as compared to the compounds of WO 00/07602. N-propanoyl- and N-cyclopropylcarbonyltetra-acetylmannosamine have proven particularly suitable (among the non-O-acylated compounds N-propanoylmannosamine has been found to be most effective.

Use of mannosamine derivatives for the stimulation of neurite growth


A multi-channel measurement device for measuring properties of human tissue, may comprise a microcontroller and first and second source/sensor complexes. The first source/sensor complex may include a first housing having a first measurement portion, a first light sensor coupled to the microcontroller and exposed to the first measurement portion, and a first plurality of light sources coupled to the microcontroller and exposed to the first measurement portion. The second source/sensor complex may include a second housing having a second measurement portion, a second light sensor coupled to the microcontroller and exposed to the second measurement portion, and a second plurality of light sources coupled to the microcontroller and exposed to the second measurement portion. The first and second source/sensor complexes are coupled to each other such that the first measurement portion is opposite the second measurement portion and human tissue may be placed between the the first and second measurement portions. The microprocessor is configured with instructions stored in non-volatile memory to individually activate each of the light sources of the first and second pluralities of light sources and to record light intensity detected by the first and second light sources while an individual light source is activated. Each combination of an individually activated light source and one of the first and second light sensors provides a distinct measurement channel for measuring the absorption spectra of human blood and tissue.

Diabetes mellitus is a metabolic condition that is characterized by high levels of glucose in the blood. This may be caused by reduced insulin production (as in Type 1 diabetes) or tissue resistance to insulin built up over time (as in Type 2 diabetes). Patients with diabetes suffer increased risks of fatality due from many different causes and generally experience a poor quality of life.
Diabetes can be combated by regular blood sugar monitoring and can even be prevented by early detection. However, more than 8 million people in the US have undiagnosed diabetes, leading to unrestricted development of the disease. Untreated diabetes has negative effects on almost every system in the body. The societal expense of undiagnosed diabetes is $33 billion annually with over $20 billion being paid by government health insurances. Early screening of diabetes and management of the symptoms has been shown to drastically improve patient outcomes compared to similar treatment years later. The potential cost savings on the order of billions of dollars and improvement to life expectancy and quality of life calls for inexpensive, wide scale screening of large populations for diabetes.
Unfortunately, the current diagnostic methods cost at least $15 per person and take 5 minutes per test. The most common FDA approved diagnostic tool is a home immunoassay kit. Each test contains four separate, biologically sterile and accurate parts, three of which are disposed of after use. The high manufacturing costs of these items combined with their lack of reusability contribute the cost of each test, making it prohibitively high for widespread screening.
Known non-invasive technologies cannot be readily adapted to screening for diabetes. For example, pulse oximetry is a known technology for noninvasively measuring blood oxygen levels. Pulse oximetry measures the ratio of oxygenated hemoglobin to deoxygenated hemoglobin in a patient's blood. From this ratio, the oxygen saturation content of a person's blood can be calculated with a reliable degree of certainty. Pulse oximetry makes use of a phenomenon described by the Beer-Lambert law. The Beer-Lambert law relates the passage of light at a constant intensity through a homogeneous substance to the path length the light travels, the concentration of the substance, and the molar absorptivity constant (a measurable property of the substance at a given wavelength). Additionally, the law states that the absorbance of a non-homogeneous substance is the sum of the absorbance of the component homogeneous substances. The Beer-Lambert law allows for an effective approximation for HbO2 at concentrations above 75%.
However, pulse oximetry, and the application of the Beer-Lambert law, is based on the principle that large structural changes exist between oxygenated and deoxygenated hemoglobin, and these have a known change in the absorption spectra. Because these two absorption spectra have an isosbestic point (e.g. they cross), one may use the absorption values of two wavelengths on either side of the isosbestic point to estimate the ratio of oxygenated hemoglobin to deoxygenated hemoglobin at HbO2 concentrations above 75%.
No such known absorption spectra map exists for blood component markers for diabetes. One may assume conformational changes occur which lead to changes in absorption spectra. But these conformational changes may "side-structural" (affecting an isolated portion section of amino acids on the Hemoglobin molecule), occur in small quantities, overlap with other variants (side-structural changes may exist on both oxygenated hemoglobin and deoxygenated hemoglobin for example), may have only small effects on natural properties (like small changes in absorption spectra), may only have local effects on natural properties (like a change in absorption spectra in a narrow wavelength range), and may be non-linear (e.g. they have complex changes in concentration as a function of blood glucose). Therefore, the Beers-Lambert Equation used for pulse oximetry is not useful to diagnose diabetes.
What is needed is a non-invasive device to perform screening of large groups of people over time in a reusable, low cost-per-use manner to screen for medical conditions, such as high levels of glycated hemoglobin. The results of such a low cost screening device may be used to make recommendations for individuals testing positive to receive traditional, higher cost diagnostic testing.

Method and apparatus for light-weight, non-invasive, point of care diabetes screening device


An electronic circuitry protection device is disclosed. The device comprises a flexible, plastic, water-proof enclosure formed to envelop the electronic circuitry of a portable or hand-held cellular telephone. The protected circuitry is mounted within the telephone housing itself, and the design of the enclosure accommodates the fasteners used for mounting and connections to external devices without compromising its protective ability.

1. Technical Field of the Invention
The present invention is directed to a device for the protection of electronic circuitry, and specifically to the protection of the internal circuitry of a portable or hand-held telephone from water damage.
2. Description of Related Art
Portable cellular phones are becoming increasing popular. As advances in cellular technology make their use easier and more affordable, cellular users avail themselves of their portable telephones for both business and personal use in a variety of environments. Some of these environments present conditions that may inadvertently result in damage to electronic equipment.
In particular, the portability of cellular phones has led to increased use near open water such as swimming pools, lakes, and rivers. Since the telephones are often used out-of-doors, calls are commonly made and received in the vicinity of fountains, tanks, and even large puddles. The hand-held units are often self-contained and not attached to the user or some larger fixture in any way. If dropped or tossed, the telephone could easily come into contact with the water, which may quickly incapacitate or damage the internal electronic circuitry. Similar damage could result from spilled or running liquids, such as beverages on a conference table, or from rainfall.
Existing protection for cellular telephones from water damage includes the use of water-tight carrying cases. These are often quite effective, but the phone must be removed from the carrying case for use; and such protection requires that the user anticipate the possible encounter with a water hazard and have the case available and employed. In addition, the seam between the two halves of the telephone housing can be sealed, but this method can be expensive, aesthetically undesirable, and only partially effective. Strategically placing gaskets or cloths in certain areas, such as the telephone's microphone opening, provide a barrier at that point, but not overall protection. The need exists for a form of electronic circuitry protection that protects substantially all of the internal circuitry, protects while the telephone is in use, requires no affirmative action by the user in order to be employed, and can be efficiently incorporated into the telephone's construction.
The invention of the present disclosure provides just such passive and continuous protection in a manner that does not add unduly to the cost of the unit and allows for easy replacement of the protective elements, if necessary.


A pre-dispersion composition comprising (i) a silsesquioxane; (ii) a dispersing agent; and (iii) a curable resin.

In the paints, coatings, inks, and adhesives ("coatings") industries, it is desirable to produce low viscosity dispersions of resins that include pigments and/or particulate fillers that exhibit excellent dispersion of the pigment and filler particles in which (i) the pigments and fillers, particularly sub-micron sized or nano-sized, pigments or fillers are de-agglomerated and reduced to their primary particle size; (ii) the subject particles are physically separated from each other or uniformly spaced in the polymer; (iii) the resultant dispersions comprising polymeric resins, pigments, and fillers, and/or combinations of pigments and fillers are stable; and (iv) the pigments and fillers do not settles or re-agglomerate. Nano-sized pigments and nano-particles can be dispersed and reduced to their primary particle size in a low viscosity format. It is further desirable that the low viscosity dispersions as described above maximize the weight percent loading of the pigments and/or fillers while minimizing the weight percent loadings of the polymer, liquid solids so that a final polymeric paint, coating, or ink composition can be produced in and of itself having very low viscosity, high tinting strength caused by optimized pigment concentrations and/or maximized mechanical properties caused by homogenous dispersion of maximized concentrations of fillers. The polymeric resin solids used as the mill base for the dispersions can be 100% liquid solids or a combination of liquid solids and solvents. There is a further, particular need in the referenced industries to have very low viscosity dispersions as described above that either have very low solvent contents or, preferably, no solvent content that can be used for producing, for example, low viscosity, 100% solvent free, radiation curable coatings. A complete description of the nature and benefits radiation curable coatings can be found in the publication entitled "Radiation Curing of Coating." Joseph V. Koleske, ASTM International, 100 Barr Harbor Drive, West Conoshohocken, Pa., 2002.
Every day, throughout the world, manufacturing companies of all sizes use paints, coatings, and inks to protect and decorate a wide variety of composite or laminate products ranging from heavy equipment parts, automobile parts, appliance casings, metal cans, and other metal sheets that are pre-painted and then shaped into finished metal containers and panels. Traditionally, solvents have been used in high concentrations to produce low viscosity paints and coatings that have high pigment and filler loadings and that can be easily and smoothly applied to plastic, wood, and metal substrates with such coatings having optimized aesthetics, opaque pigment color, and optimized mechanical and chemical resistance properties. Whereas traditional solvent-base coatings have solvent contents from 40% to 90% by total coating weight, there is a growing demand and need by industry to dramatically reduce or eliminate the use of solvents in coatings due to environmental and safety concerns. High solids coatings and radiation curable coatings are considered to be ecologically friendly and contain little or no solvents. These coatings are also far more energy efficient due to reduced energy costs for curing and other economic efficiencies, such as accelerated curing times. There is a need for low viscosity, high filled pigment and/or filler dispersions in polymeric resins that are highly stable and homogenous that can be used to produce commercially viable, low viscosity paints, coatings, and ink compositions that are (i) low in solvent concentration or solvent free, (ii) have excellent application characteristics such as flow and leveling equal to their solvent-based counterparts; (ii) and are equally as functional in aesthetic and physical quality as high solvent coatings.
Dispersions are often quite expensive and it is highly desirable to have a low viscosity dispersion having a high concentration of pigments and/or particulate fillers so that optimized amounts of dispersion are used in the final coating compositions. Low viscosity, highly filled dispersions can be used to make very thin coating films, having excellent opaque colors. Very thin films, applied to substrates, use coatings more efficiently, lowering coating costs, lowering curing energy costs, while increasing productivity. On the other hand, low viscosity, highly filled dispersions can be used to make thick coating compositions for casting such as casting prototypes. In any case, low viscosity, highly filled dispersions are advantageous when optimizing finished coating viscosities, color fastness, and mechanical properties.
The publication, Hyperdispersants, Technology & Benefits, The Lubrizol Corporation, HD-002, July, 2008, teaches that polymeric hyperdispersants produce improved pigment dispersions by attaching polymer chains to an anchoring group such as a pigment which separates or de-agglomerates the pigment particles and sterically stabilizes the dispersion of particles. The publication further teaches that the hyperdispersant or polymeric chain competes with the dispersion resin and other additives for attachment to pigment or particle surfaces. Therefore, it is taught to use only a hyperdispersant such as Solsperse® to attach to either a surface treated or an un-surface treated pigment or particle in a dispersion of liquid resin and pigments particles. Any other additives should be added after the pigment dispersion is let down and mixed into the final coating formulas so that other dispersing and surfactant additives do not detach the hyperdispersant (anchoring polymer chain) from the pigment particle surface. The publication goes on to teach that pigment particle surfaces should, preferably, not be treated since the hyperdispersant will not attach to a treated surface. It also teaches that it is preferred to use a high viscosity resin because a low viscosity resin wets the pigment surface and also competes with the hyperdispersant for attachment to the pigment surface, and, as such, better results can be attained by using a higher viscosity resin. When applied as directed, the pigment dispersion containing a hyperdispersant, liquid resin, a pigment, and solvents will have a lower viscosity than a similar pigment dispersion without a hyperdispersant. The publication fails to teach the use of a hyperdispersant in combination with other polymeric dispersants or chemicals, and, in fact, teaches not to use a hyperdispersant with any other dispersant or chemical when making pigment particle dispersions because the pigments will re-agglomerate and the pigment dispersion will be unstable. Dispersions made from hyperdispersants alone are limiting in producing a low viscosity dispersion with high concentrations of pigments and/or particles.
U.S. Pat. No. 6,660,374 B2 discloses radiation curable compositions that comprise solid, amorphous glass particles that are transparent to radiation, such as UV light, that improve the radiation curing behavior of such coatings. The patent teaches that such glass particles can be de-agglomerated and more fully dispersed by silane surface treating the glass particles prior to dispersing the glass particles into the coating. However, the patent does not disclose or teach the use of dispersants added to a resin to make a pre-dispersion of either pigments and/or glass particles.
POSS® Titania, Hybrid Plastics, February, 2007 discloses the use of POSS (Polyhedral Oligomeric Silsesquioxane) silanols to coat the surfaces of silicas and metal oxides, such as TiO2, in order to enhance dispersion and make a dispersion more stable. The publication also teaches that the POSS silanols are used alone to treat pigment surfaces such as TiO2. The publication does not teach or disclose the use of POSS silanols with hyperdispersants. Dispersions made from POSS alone are limiting in producing a low viscosity dispersion with high concentrations of pigments and/or particles.

Dispersions and related coatings and cured articles


Label information used by a downstream LSR is mirrored on an upstream LSR. In particular, a copy of the label information database in the downstream LSR from LDP sessions is stored on the upstream LSR. The label information database and corresponding mirror are synchronized. The mirror is employed to facilitate recovery from control plane failure through comparison of the label information database with the mirror. For example, the intersection of the label information database and the mirror may be calculated and employed as the updated label information database and mirror.

Techniques for protecting and restoring services from network failures are well known. The techniques typically focus on failures in the data plane, although in some conventional networks the distinction makes little difference. SONET/SDH network failures, for example, necessarily imply simultaneous control plane and data plane failure because control messages and user information are transmitted together in frames. However, recently developed optical network architectures having separate control and data planes present difficulties. Known protection and restoration techniques may be employed with such optical networks to recover from faults in the data plane. However, these techniques appear to be less useful against control plane failure. It would therefore be desirable to have protection and restoration capability for the control plane.

Control plane failure recovery in a network


A cable is disclosed that can be used to reinforce a crown protection ply and/or a stiffener (9) in tires for heavy industrial vehicles. Also disclosed are composite fabrics that can be used as crown protection plies and/or as stiffeners (9) in such tires, and the tires themselves. The cable comprises three strands twisted together in helix of pitch p2, each consisting of two metallic wires twisted together in helix of pitch p1, these wires having diameters (d1, d2), (d1′, d2′), (d1″, d2″) for the strands, respectively, such that the cable satisfies the following conditions:

Steel cables for tires as a rule consist of pearlitic (or ferrite-pearlite) carbon steel wires, hereinafter "carbon steel", with a carbon content generally between 0.2% and 1.2%, the diameter of these wires being most often between about 0.10 and 0.40 mm. These wires are required to have very high tensile strength, generally higher than 2000 MPa and preferably higher than 2500 MPa, obtained thanks to the structural hardening that takes place during the cold drawing of the wires. The wires are then assembled in the form of cables or strands, and this also requires the steels used to have sufficient torsional ductility to withstand the cabling operations.
In a known way, tires for industrial vehicles such as heavy vehicles usually comprise a carcass reinforcement anchored in two beads and surmounted radially by a crown reinforcement comprising one or more working crown plies and one or more crown protection plies over the working crown ply or plies, the said crown reinforcement itself being surmounted by a tire tread joined to the beads by two sidewalls.
The protection plies, which can be deformed thanks to a degree of elasticity, are mainly intended to impede the penetration of foreign bodies radially into the tire during rolling.
To reinforce the protection plies of tires for industrial vehicles such as heavy vehicles, nowadays it is customary to use strand cables (or strand "cords" in English), which are ssembled by the known technique of stranding and consist, by definition, of a plurality of metallic strands twisted together in helix, each strand comprising steel wires also twisted together in helix. Note that most of the wires used in these cables for crown protection plies have a diameter typically above 0.20 mm, for example close to 0.30 mm, this diameter being in particular larger than that of the wires used in the carcass reinforcement of heavy-vehicle tires.
As strand cables currently used to reinforce the crown protection plies of heavy-vehicle tires, one may mention for example a cable with the formula (4×2), consisting of 4 strands twisted together in helix, each consisting of 2 metallic wires twisted together in helix.
The cables for crown protection plies are designed on the one hand to confer optimum flexibility on the ply containing them, so that the crown protection ply can best conform to the shape of an obstacle it encounters during rolling, and on the other hand to allow the ply to resist the penetration of foreign bodies radially into it.
Note also that these strand cables must be as thoroughly impregnated as possible by the rubber, so that the latter penetrates into all the spaces between the wires constituting the cables. In effect, if this penetration is insufficient, empty channels form along the cables and corrosive agents such as water, which can penetrate into tires for example due to cuts or other aggressions of the tire's crown reinforcement, make their way along those channels through the said reinforcement. The presence of this moisture plays an important part in causing corrosion and accelerating the processes of fatigue ("fatigue-corrosion" phenomena) compared with use in a dry atmosphere.
On the other hand, each bead of a tire for a heavy industrial vehicle is generally provided with a stiffener designed to reinforce it, each stiffener comprising at least one ply of cables extending axially on the outside of the upturn of the carcass ply. These cables make an angle generally between 15° and 30° relative to the circumferential direction of the tire. In some cases each stiffener can extend along the upturn of the carcass ply both axially outside and radially inside the upturn, essentially forming an L when viewed in the meridian cross-section of the tire.
These stiffeners have an overall damping function which tends in particular to minimise the phenomenon of "deradialisation" of the carcass reinforcement of the tire each time it is flattened against the ground over which it is rolling, by taking up the compression forces connected with the flattening and minimising the wear against the rim.
To reinforce the plies, constituting these stiffeners, the cables most often used are layered steel cables consisting of a central core and one or more concentric layers of wires arranged around the core.
The most widely used layered cables in these stiffeners for heavy-vehicle tires are ones having the formula (L+M) or (L+M+N). As is known, these cables are formed of a core of L wire(s) surrounded by at least one layer of M wires itself sometimes surrounded by an outer layer of N wires, L generally varying from 1 to 4, M from 3 to 12, N from 8 to 20, depending on the case, and the whole if necessary being surrounded by a wrapping wire wound around the last layer.
Like the cables for crown protection plies, it is also important that these layered cables for stiffeners are as fully impregnated as possible by the rubber, so that it will penetrate between the wires constituting the cables to prevent corrosive agents from making their way into empty channels along the cables.
For example, layered cables of structure (3+9+15) have been described, which consist of an inside layer of 3 wires surrounded by an intermediate layer of 9 wires and a saturated outer layer of 15 wires, for example provided with a wrapping wire, as described in the documents EP-A-176 139 (or U.S. Pat. No. 4,651,513), EP-A-497 612(or U.S. Pat. No. 5,285,836), EP-A-669 421 (or U.S. Pat. No. 5,595,057), EP-A-709 236 (or U.S. Pat. No. 5,836,145),EP-A-744 490 (or U.S. Pat. No. 5,806,296) or EP-A-779 390 (or U.S. Pat. No. 5,802,829).
A major disadvantage of these cables with formula (3+9+15) is that they cannot be penetrated throughout by the rubber, in particular because of the saturated structure of the outer layer and the presence of a channel or capillary at the centre of the three core wires, which remains empty after impregnation by the rubber and is therefore available for the propagation of corrosive agents such as water.

Cords for reinforcing heavy vehicle tires

Abstract: (i)0.25 < d1 < 0.45(ii)0.25 < d2 < 0.45(iii)0.25 < d1′ < 0.45(iv)0.25 < d2′ < 0.45(v)0.25 < d1″ < 0.45(vi)0.25 < d2″ < 0.45(vii)2 < p1 < p2 < 10.


Time-based partitioning of a data set is applied to capture updates to the data set in a copy of the data set. Items that have been updated in a data set with in a time period are identified. Partitions of the data set that include the updated items are created according to a partitioning scheme. The created partitions are grouped in a storage location for the time period in a file structure that stores a copy of the database. A latest version of the copy of the data set may be accessed according to latest partitions of the data set stored in the different locations of the file structure.

As the technological capacity for organizations to create, track, and retain information continues to grow, a variety of different technologies for managing and storing the rising tide of information have been developed. Such advances in storage capabilities, both in terms of storage capacity and processing capacity, are not without cost. For instance, the increasing amount of data that organizations want to store in highly performant analytical systems may result in scenarios where some copies of data sets are separately stored in archives, or other types of storage systems, separate from the source data set. In this way, the separately stored copies may reduce the burden of maintaining more data in costly analytical systems, as less costly storage technologies can be used for maintaining copies which may only be occasionally accessed. However, in such scenarios changes made to the source data for these copies may still need to be replicated to the separately stored copies in order to maintain a useful, accurate, or consistent copy. Therefore, techniques that can efficiently replicate changes from source data to copies are highly desirable.
While embodiments are described herein by way of example for several embodiments and illustrative drawings, those skilled in the art will recognize that embodiments are not limited to the embodiments or drawings described. It should be understood, that the drawings and detailed description thereto are not intended to limit embodiments to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope as defined by the appended claims. The headings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description or the claims. As used throughout this application, the word "may" is used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning must). Similarly, the words "include," "including," and "includes" mean including, but not limited to.
It will also be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first contact could be termed a second contact, and, similarly, a second contact could be termed a first contact, without departing from the scope of the present invention. The first contact and the second contact are both contacts, but they are not the same contact.

Time-based partitioning to avoid in-place updates for data set copies


A method for designing a reference signal to be transmitted in a multiplexed cellular system is described. A first set of matrices that comprises a plurality of matrices is selected. An optimal partition of the first set of matrices is determined. A third matrix is formed. The third matrix represents a cross-correlation of a second matrix and each of the plurality of first matrices. A minimum corresponding to the first set of matrices is set. The second matrix is updated using the minimum corresponding to the first set of matrices. Each column of the second matrix is scaled by a first value.

A wireless communication system typically includes a base station in wireless communication with a plurality of user devices (which may also be referred to as mobile stations, subscriber units, access terminals, etc.). The base station transmits data to the user devices over a radio frequency (RF) communication channel. The term "downlink" refers to transmission from a base station to a user device, while the term "uplink" refers to transmission from a user device to a base station.
Orthogonal frequency division multiplexing (OFDM) is a modulation and multiple-access technique whereby the transmission band of a communication channel is divided into a number of equally spaced sub-bands. A sub-carrier carrying a portion of the user information is transmitted in each sub-band, and every sub-carrier is orthogonal with every other sub-carrier. Sub-carriers are sometimes referred to as "tones." OFDM enables the creation of a very flexible system architecture that can be used efficiently for a wide range of services, including voice and data. OFDM is sometimes referred to as discrete multi-tone transmission (DMT).
The 3rd Generation Partnership Project (3GPP) is a collaboration of standards organizations throughout the world. The goal of 3GPP is to make a globally applicable third generation (3G) mobile phone system specification within the scope of the IMT-2000 (International Mobile Telecommunications-2000) standard as defined by the International Telecommunication Union. The 3GPP Long Term Evolution ("LTE") Committee is considering OFDM as well as OFDM/OQAM (Orthogonal Frequency Division Multiplexing/Offset Quadrature Amplitude Modulation), as a method for downlink transmission, as well as OFDM transmission on the uplink.
Wireless communications systems (e.g., Time Division Multiple Access (TDMA), Orthogonal Frequency-Division Multiplexing (OFDM)) usually calculate an estimation of a channel impulse response between the antennas of a user device and the antennas of a base station for coherent receiving. Channel estimation may involve transmitting known reference signals that are multiplexed with the data. Reference signals may include a single frequency and are transmitted over the communication systems for supervisory, control, equalization, continuity, synchronization, etc. Wireless communication systems may include one or more mobile stations and one or more base stations that each transmits a reference signal. The reference signals for 3GPP may be generated by computer algorithms, however, the particular algorithms and their criteria for effectiveness are not specified. As such, benefits may be realized by providing systems and methods for improving the design of reference signals for spatially multiplexed cellular systems.

Systems and methods for designing a reference signal to be transmitted in a multiplexed cellular system


A turbocharger assembly is provided. The turbocharger assembly includes a turbine assembly having at least one internal aerodynamic surface and a compressor assembly having at least one internal aerodynamic surface. At least one of the at least one internal aerodynamic surface of the turbine assembly and the at least one internal aerodynamic surface of the compressor assembly is at least partially coated with a catalyst material. The internal aerodynamic surfaces of the turbine assembly may include a volute, variable geometry mechanism, turbine wheel, and outlet. The internal aerodynamic surfaces of the compressor assembly may include and inlet, compressor impeller, diffuser, variable geometry mechanism, and a volute. An internal combustion engine incorporating the disclosed turbocharger assembly is also provided.

Internal combustion engines may use an exhaust driven compressor or turbocharger assembly to increase the manifold air pressure or MAP, thereby providing increased engine performance for a given engine displacement. A typical turbocharger assembly includes a turbine assembly in fluid communication with the exhaust gases and a compressor assembly in fluid communication with the inlet gases. A portion of the energy contained within the exhaust gases operate to spin or rotate a turbine wheel disposed within the turbine assembly. The turbine wheel is connected to a compressor impeller, disposed within the compressor assembly, through a common shaft. As such, the turbine wheel and compressor impeller rotate unitarily. In operation, as the exhaust gases rotate the turbine wheel, the rotating compressor impeller inducts or draws intake gases into the compressor assembly where it is pressurized for subsequent introduction to the internal combustion engine.
Recent advances in turbocharger design have led to the introduction of so-called variable geometry turbochargers. The variable geometry turbocharger typically includes a plurality of movable vanes disposed in one or both of the compressor assembly and turbine assembly, which operate to vary the operating characteristics of the turbocharger. Such variable geometry turbochargers may be effective in reducing so-called "turbo lag" in addition to improving the operating efficiency of the turbocharger assembly over a range of engine speeds. The accumulation of deposits, such as hydrocarbons and soluble organic fraction on the internal aerodynamic surfaces of the compressor housing and/or turbine housing may reduce the efficiency of the turbocharger and possibly cause sticking of the movable vanes contained therein.

Turbocharger assembly with catalyst coating


The present invention relates to gelatinous elastomers, methods for making gelatinous elastomers, methods for using gelatinous elastomers, products made from gelatinous elastomers, and products which include gelatinous elastomers as a component or ingredient. More particular, the invention includes a gelatinous elastomer formed from a combination of a block copolymer of the general configuration A-B-A and a plasticizer. The preferred A-B-A copolymer of the invention is polystyrene-hydrogenated poly(isoprene+butadiene)-polystyrene and the preferred plasticizer is either mineral oil or a combination of mineral oil and resin. Various other components may be included in the preferred recipes according to the invention.

A. Field of the Invention
The present invention relates to gelatinous elastomers, methods for making gelatinous elastomers, methods for using gelatinous elastomers, products made from gelatinous elastomers, and products which include gelatinous elastomers as a component or ingredient. More particularly, the invention includes a gelatinous elastomer formed from a combination of a block copolymer of the general configuration A-B-A and a plasticizer. The preferred A-B-A copolymer of the invention is an ultra high molecular weight polystyrene-hydrogenated poly(isoprene+butadiene)-polystyrene and the preferred plasticizer is either mineral oil or a combination of mineral oil and resin. Various other components may be included in the preferred recipes according to the invention.
B. Description of Related Art
For the benefit of the reader's comprehension of work that had been performed before the invention and the background against which the invention was made, an in-depth discussion of related and background art is provided below.
1. Early Oil-Extended Triblock Copolymer Compositions
U.S. Pat. No. 3,485,787, issued in the name of Walter R. Haefele et al., which is hereby incorporated by reference, discloses oil-extended triblock copolymers of the general configuration A-B-A, wherein A is an alkenyl aromatic hydrocarbon polymer block and B is a conjugated diene hydrocarbon polymer block. The '787 patent explains that alkenyl aromatic hydrocarbons are useful as the A blocks and that the B portion can be any four to ten carbon conjugated diene (col. 4, lines 4-7).
However, only polystyrene-polyisoprene-polystyrene, poly(.alpha.-methylstyrene)-polyisoprene-poly(.alpha.-methylstyrene) and polystyrene-polybutadiene-polystyrene are listed in the '787 patent as species of triblock copolymers suitable for use in that material (col. 3, lines 12-15). Although broad average molecular weight ranges are disclosed for each component (A having an average molecular weight of about 4,000 to 115,000 and B having an average molecular weight of about 20,000 to 450,000), test data is only listed for triblock copolymers wherein the A blocks each have an average molecular weight of about 15,000 to about 42,000 and the B blocks each have an average molecular weight of about 23,000 to about 75,000 (col. 5, line 74 and col.7, Table 3). Further, the '787 patent describes the amount of extending oil as 5 to 100 parts by weight based on 100 parts by weight block copolymer (i.e., about 2.5 weight percent to about 50 weight percent oil based on the combined weight of the oil and copolymer)(col. 2, lines 52-53 and col. 5, lines 21-23). While the tensile strength of those materials is high (typically greater than 1,000 psi)(col. 7, Table 3), their percent elongation is low (the highest stated value being 930%) (Id.). Further, Applicant believes that the materials of the '787 patent have a very high durometers when compared with the gelatinous elastomers of the present invention.
U.S. Pat. No. 3,676,387, issued in the name of James A. Lindlof, which is hereby incorporated by reference, discloses an oil-based elastomer which is five to thirty weight percent triblock copolymer of the general configuration A-B-A and seventy to ninety-five percent non-aromatic paraffinic oil (col. 2, lines 9-25). The patent defines A as a glassy or resinous non-elastomeric thermoplastic polymer block with a glass transition temperature above room temperature, having an average molecular weight of between about 2,000 and 100,000 and which is relatively incompatible with the elastomeric polymer block B (col. 1, lines 47-53). B is defined as an elastomeric polymer block of a conjugated diene, the average molecular weight being about 15,000 and about 1,000,000 and having a glass transition temperature considerably below that of the A blocks (col. 1, lines 53-57). The '387 patent also states that A:B weight ratios of 10:90 to 50:50 are useful (col. 1, lines 59-61). The oil weight percentage of the oil-extended elastomers of that patent, based on the combined weight of oil and elastomer, is in the range of 70% to 95% (col. 2, lines 9-25). The preferred materials of that patent have a low elasticity modulus, in the range of 1 to 10 psi for 200% elongation of a one square inch specimen (col. 1, lines 40-44). Applicant also believes that the preferred materials of the '387 patent have low tensile strength.
Although the '387 patent states that an average molecular weight range of 15,000 to 250,000 for the B mid-block is preferred and that the A blocks constitute from 10% to 50% of the total polymer weight (10:90 to 50:50 A:B weight ratios), the oil-extended elastomers were near the lower end of the disclosed weight ranges. One of the patent's examples describes an oil-extended elastomer which utilizes a styrene-butadiene-styrene block copolymer having an average molecular weight of only about 100,000, of which the average molecular weight of the B mid-block is about 70,000 (col. 3, lines 46-49). Thus, the styrene:butadiene weight ratio of that particular triblock copolymer is about 30:70.
Similar elastomeric materials are described in U.S. Pat. No. 3,827,999 issued in the name of Ronald K. Crossland, which is hereby incorporated by reference. That patent discloses block copolymers extended in 70 to 98 weight percent oil (col. 2, lines 8-9). The use of monoalkenylarene end blocks which are block polymerized with a conjugated diene is preferred (col. 2, lines 23-28). The average molecular weight range of the monoalkenylarene blocks used in Crossland's material is 5,000 to 75,000 (col. 2, lines 66-69). The average molecular weight range of the conjugated diene blocks used in that material is 25,000 to 250,000 (col. 2, lines 69-72).
However, the preferred block copolymers of that patent have a much lower average molecular weight: the monoalkenylarene blocks preferably having a molecular weight in the range of 8,000 to 65,000 and the conjugated diene blocks preferably having a molecular weight in the range of 35,000 to 110,000 (col. 2, lines 66-72). Moreover, the examples given in the patent utilized triblock copolymers of the general configuration A-B-A, wherein A represents a monoalkenylarene polymer and B represents a polymer composed of conjugated diene molecules, and having total molecular weights of only 57,000 (col. 4, line 3) and 70,000 (col. 4, line 2), with A:B ratios of about 33:67 and 29:71, respectively. The '999 patent states that the materials specifically preferred are polystyrene-hydrogenated isoprene-polystyrene and polystyrene-hydrogenated butadiene-polystyrene (col. 2, lines 55-59). Applicant believes that preference is due to the improved strength of materials which included triblock copolymers with hydrogenated midblocks over similar materials with non-hydrogenated midblocks, which were the subject of the '387 patent.
While Crossland states that his materials exhibit "no more than slight indications of bleeding as compared with the heavy bleeding which occurs with the compositions containing the non-hydrogenated block polymer" (col. 4, lines 43-46) and higher strength than similar materials with triblock copolymers having non-hydrogenated midblocks, they nonetheless exhibit very low tensile strength and poor elongation. Of the materials examined in the patent, the highest tensile strength (at break) noted was merely 80 psi (see tables at col. 3, lines 68-75 and col. 4, lines 57-64). The highest percentage elongation (at break) noted in the patent was only 850 (Id.). A further problem with Crossland's materials is the decrease in percent elongation with an increased amount of oil (Id.).
A styrene-ethylene butylene-styrene (SEBS) block copolymer, which has the general configuration A-B-A, is described in U.S. Pat. No. 4,176,240, issued in the name of Raffaele A. Sabia, which is hereby incorporated by reference. Sabia sought to meet a need for a more solid, handleable gel material (col. 2, lines 35-40). Sabia's material includes 5 to 10 weight percent SEBS, 87 to 93 weight percent naphthenic oil and 0 to 6 weight percent polyethylene, wherein all weight percentages are based upon the total weight of the material (Table I). Those materials are stated as having advantages for waterproofing (col. 2, lines 8-9), handling (col. 2, lines 35-40) and low temperature flexibility (See col. 2, lines 19-22, which identifies a need for such a property).
Sabia specifies that the SEBS useful in his material has a styrene to rubber ratio (A:B) of about 0.4 (i.e., 40:60)(col. 2, lines 33-44). In fact, the materials used in the examples had styrene to rubber ratios of 0.39 and 0.41 (i.e., 39:61 and 41: 59, respectively)(Table I, Constituent A). The experimental results listed in that patent demonstrate that Sabia's materials possess low tensile strength and low percent elongation. None of the results show a tensile strength of even 5 psi (Table I). The greatest amount of elongation shown is 129% (Id.).
Sabia states that during experimentation, styrene-isoprene-styrene (SIS) was used as a substitute for SEBS (col. 5, lines 33-35). However, he noted that the high amount of tackiness of the SIS-containing material made it less handleable and therefore undesirable (Id.).
In U.S. Pat. No. 4,259,540, also issued in the name of Sabia and which is incorporated herein by reference, the list of useful components for making compositions similar to those of the '240 patent was broadened. For example, in addition to naphthenic oils, the '540 patent describes use of paraffinic oils and mixtures of naphthenic and paraffinic oils (col. 2, lines 29-31). Similarly, the styrene to rubber ratio (A:B) range of the SEBS was increased from about 0.4 to approximately 0.2 to 0.5 (i.e., 20:80 to 50:50) and is stated as preferably being about 0.4 (col. 2, lines 35-38). In addition, a fourth element, isopropyl phenyl-phenyl phosphate, was added to the material to inhibit oil synersis, which implies that oil synersis may have been a problem with the material of the Sabia '240 patent (Table 1, footnote).
Despite Sabia's increased ranges in the '540 patent, the examples of that patent show no increase in either tensile strength or elongation over those of the '240 patent (Table 1).
U.S. Pat. No. 4,351,913, issued in the name of Naren I. Patel, which is hereby incorporated by reference, discloses a cable-insulative material that possesses properties similar to those of the materials described in the Sabia '240 patent, along with improved dielectric, high temperature drip and density characteristics. The material of the '913 patent includes a triblock copolymer of the general configuration A-B-A, chosen from SEBS, 7IS and styrene-butadiene-styrene (SBS)(col. 4, lines 11-14), and paraffinic or naphthenic mineral oil (col. 4, line 15). In addition, glass or ceramic microspheres and/or an additive may be used to make that material (col. 4, lines 19-20).
The examples of the '913 patent disclose mixtures composed of I to 30 weight percent styrene block copolymer, 52 to 82 weight percent either naphthenic or paraffinic mineral oil, 1 to 31 weight percent inorganic (e.g., glass or ceramic) hollow microspheres and 1 to 13 weight percent additive, if desired-such as polyethylene or glycerol hydroxy sterate (Table 3, the various constituents are identified throughout the text and tables).
Patel's preferred copolymers have very specific styrene to rubber (A:B) ratios: he prefers use of an SEBS having an A:B ratio of 0.39 to 0.41 (col. 4, lines 30-31), SBS having an A:B ratio of approximately 0.39 (col. 4, lines 37-38) or SIS having an A:B ratio of approximately 0.16 (col. 4, lines 42-43). Although use of other block copolymers in that material are noted, Patel's preferred formulations all include SEBS.
The '913 patent does not discuss the strength and elongation properties of the materials disclosed therein (col. 16, lines 65-68, which references Table 3, constituents A and B are identified at col. 4, 34-36).
2. John Chen's Thermoplastic Elastomer Gelatinous Compositions
Having familiarized himself with various gels available in the art, the inventor considers the gel compositions of John Chen to be the best available in the prior art, although the Chen gels are seriously deficient in several important areas, and these deficiencies are addressed by the invention.
U.S. Pat. No. 4,369,284, issued in the name of John Y. Chen, which is hereby incorporated by reference, discloses an oil-extended elastomer composition that includes about 6 to about 25 weight percent SEBS and about 75 to about 94 weight percent oil (col. 2, lines 8-24). The SEBS component of Chen's material has a styrene to rubber (A:B) ratio within the range of between 31:69 and 40:60 (col. 2, lines 25-34). Chen's preferred A:B ratio is 33:67 (col. 2, lines 30-31). However, according to Shell Chemical Company, KRATON.RTM. G1651, which is used in Chen's examples, has an A:B ratio of 32:68.
Chen's material is prepared by blending together the components including other additives as desired at about 23.degree. C. to about 100.degree. C., forming a paste-like mixture, and further heating said mixture uniformly to about 150.degree. C. to 200.degree. C. until a homogeneous molten blend is obtained (col. 3, lines 25-31). A heated vessel with a stirrer is all that is required to carry out Chen's melt blending process (Id.), although Chen's process takes many hours and much labor to complete.
The '284 patent discloses a 20 weight percent SEBS, 80 weight percent 200 weight paraffinic oil material which has a low breaking (i.e., tensile) strength of only 4.times.10.sup.6 dyne/cm.sup.2 (58 psi) and a low percent elongation of only 1,700% (Table I, col. 4, line 56 to col. 5, line 13). Further problems with Chen's material include relatively high amounts of oil bleed and tack (despite Chen's claim that the material was "substantially without oil bleedout" (col. 3, line 18)), each of which are unacceptable in various applications.
U.S. Pat. No. 4,618,213, issued in the name of John Y. Chen, which is hereby incorporated by reference, describes a material similar to that disclosed in Chen's previous patent applications and in the '284 patent. The material and the process for making the material are substantially the same as the material and process disclosed in the '284 patent. In the '213 patent, Chen again changed the average molecular weight range for plasticizing oils useful in the material, this time by stating that plasticizing oils having molecular weights of less than about 200 and greater than about 700 would be useful in his material (See col. 3, lines 29-31). The '213 patent also included a number of additional examples that did not appear in the '284 patent, including examples which listed the rigidity ranges of various materials having SEBS of different A:B weight ratios.
For each of the materials tested, depending upon the amount of oil used, rigidity ranged from about 20 to about 700 gram Bloom (Examples XI-XIV, col. 8, lines 15-45). However, Chen did not disclose any of the other physical properties of those materials. Therefore, Applicant believes that the tensile strength and percent elongation of those materials do not exceed the corresponding properties of the Chen material which contains 20 weight percent 33:67 SEBS and 80 weight percent of 200 weight paraffinic mineral oil (Table I, col. 6, lines 18-38). Chen does not state this specifically, however.
U.S. Pat. No. 5,262,468, issued in the name of John Y. Chen, which is hereby incorporated by reference, provides about the same basic disclosure of Chen's material as the '284 and '213 patents. However, in apparent realization that the molecular weight of the triblock copolymers of his composition provided beneficial physical properties such as tensile strength and percent elongation, Chen downplayed the importance of the SEBS A:B ratio, and broadened the A:B ratio range useful in his materials to about 20:80 or less to about 40:60 or higher (col. 3, lines 27-30). He stated that triblock copolymers having A:B ratios below 31:69 may be used, but they are less preferred due to their decrease in the desirable properties of the final composition (col. 4, lines 5-9).
Chen then noted the importance that, in combination with the A:B ratio range, the triblock copolymers used in his invention have a Brookfield solution viscosity of at least about 1,800 centipoises (cps)(col. 4, 36-42)(KRATON.RTM. G-1651 has a solution viscosity, 20% solids in 80% toluene, at 25-30.degree. C. of about 2,000 cps). Solution viscosity is related to the molecular weight of the copolymers. In addition, he included a long list of potential additives and more examples. However, no mention was made of the utility of many of the potential additives. Chen then listed several apparatus that could be made with his material.
One very interesting point about the '468 patent is the elongation at break value that is missing from Table I. Each of Chen's issued patents include a Table I, and the Table I of each patent is almost identical. However, Table I of every Chen patent which issued subsequent to U.S. Pat. No. 4,618,213 omits the elongation at break value.
Despite the missing elongation value, the '468 patent did not disclose a material with physical characteristics superior to those of the materials of Chen's '284 and '213 patents. Similarly, U.S. Pat. No. 5,508,334, which is hereby incorporated by reference, and which also issued in the name of John Y. Chen, disclosed a material having very similar composition and physical properties to those of the '284, '213 and '468 patents. The material of the '334 patent did, however, include the addition of a "minor amount" of various polymers to the material (col. 4, line 66 to col. 5, line 12). In the '334 patent, Chen's preferred gel is a mixture of (i) 100 parts by weight of a high viscosity poly(styrene-ethylene-butylene-styrene) triblock copolymer, (ii) from about 300 to about 1600 parts by weight of a plasticizing oil; and (iii) a minor amount of one or more homopolymers or copolymers (col. 2, lines 24-36). Applicant found the specification of the '334 patent confusing because it failed to identify the purpose of adding the homopolymers or copolymers to the material. SEBS useful in the material of the '334 patent has a Brookfield viscosity of not less than about 1,800 cps, and preferably about 2,000 cps or higher. Typically, the Brookfield viscosity values can range from about 1,800 cps to about 16,000 cps. Less typically, the Brookfield viscosity values can range from about 1,800 cps to about 30,000 cps or higher (col. 2, lines 37-45). However, KRATON.RTM. G-1651, Chen's preferred SEBS copolymer, has a Brookfield viscosity, 20% solids in 80% toluene, of only about 2,000 cps ('334, Table I, footnote 4). The '334 patent states that the styrene end block to ethylene and butylene center block ratios should be in the range of 20:80 or less to 40:60 or higher (col. 3, lines 11-14).
In addition, several patents which disclose articles made out of Chen's elastomeric materials have issued in the name of John Y. Chen. U.S. Pat. No. 4,618,213, which is hereby incorporated by reference, primarily discloses Chen's gelatinous material, but also states that objects such as lenses, rods, prisms and hemispheres can be made from his gel.
In U.S. Pat. No. 5,153,254, issued in the name of John Y. Chen, which is hereby incorporated by reference, Chen claims a reusable lint remover made from his gelatinous material. The patent does not contain a detailed description of such a device or of how it would be made.
U.S. Pat. Nos. 5,239,273 and 5,475,890, which are each hereby incorporated by reference, also issued in the name of John Y. Chen, each disclose reusable swabs made from Chen's gelatinous material. However, the A:B ratio range of the SEBS triblock copolymer used in that material--20:80 to 40:60--('890, col. 4, lines 6-9) is much broader than the SEBS A:B ratio range of the materials disclosed in the following Chen patents: '284 and '213.
U.S. Pat. No. 5,334,646, issued in the name of John Y. Chen, which is hereby incorporated by reference, claims an article of manufacture made from essentially the same material as that disclosed in Chen's '468 patent. Chen's list of articles of manufacture includes such things as a vibration damper, a vibration isolator, a wrapper, a hand exerciser, a dental floss, a crutch cushion, a cervical pillow, a bed wedge pillow, a leg rest cushion, a neck cushion, a mattress, a bed pad, an elbow pad, a dermal pad, a wheelchair cushion, a helmet liner, a hot or cold compress pad, an exercise weight belt, a swab, a traction pad, an orthopedic shoe sole, or a splint, a sling, or a brace cushion for the hand, wrist, finger, forearm, knee, leg, clavicle, shoulder, foot, ankle, neck, back or rib (col. 6, line 37 to col. 7, line 41). In addition, the '646 patent mentions that the material may be cast onto open cell substrates (col. 7, lines 38-59).
U.S. Pat. No. 5,336,708, issued in the name of John Y. Chen, which is hereby incorporated by reference, discloses a layered composite which includes layers of Chen's previously described materials physically interlocked with layers of other materials. The composite may contain more than one layer of Chen's materials, each layer having the same or different rigidities (col. 3, lines 11-13). The remaining layers are selected from the group consisting of foam, plastic, fabric, metal, concrete, wood, glass, ceramics, synthetic resin, synthetic fibers or refractory materials (col. 3, lines 40-45).
In the above-identified patents, Chen discloses various gel compositions which relate to poly(styrene-ethylene-butylene-styrene) (such as Shell's KRATON.RTM. G 1651), a plasticizing oil, and appropriate additives. Applicant, whose employer is a licensee of Chen's patents, found in working with Chen's gel that it had insufficient tensile strength, excessive oil bleed, and higher cost per unit volume. As described below, Applicant has created a gel, method for making the gel, and method for making articles from the gel that eliminates many of the problems found with the Chen gel.
Some of Chen's patents heavily emphasize the ratio of end block (A) to mid block (B) weights. Generally these ratios fall in the range of 19:81 to 52:49 (See, e.g., the '334 patent). Applicant believes that Mr. Chen attributed the more desirable performance of his gel, in comparison with the prior art, to the end block to mid block ratios. As explained below, Applicant's invention achieves substantially better performance than Chen's gel. However, Applicant believes that the material of the present invention performs better due to the chemical and physical characteristics of the particular A-B-A elastomer rather than because of the end block to mid block ratios of the A-B-A block copolymer.
As explained above, Chen prepared his gel compositions by blending together the components and additives at about 23.degree. to about 100.degree. C., forming a paste like mixture and further heating the mixture to about 105.degree. C. to 200.degree. C. until a homogeneous molten blend is obtained. Thereafter a desired article can be molded (See '334, col. 5, lines 25-45 for a description of Chen's gel manufacturing process). When Applicant's employer licensed Chen's patents, Chen instructed Applicant's employer on Chen's preferred gel composition and how to make it. The process was a complicated, multi-step process that took Applicant a long time to complete. Applicant believed there to be disadvantages in such a process because it was highly consumptive of energy and labor, required great amounts of time, and caused degradation of some of the gel components, so Applicant developed the quicker, simpler and cheaper processes explained below.
3. Post-Chen Oil-Extended Triblock Copolymer Compositions
Another relevant piece of prior art is Technical Bulletin number SC:1102-89, entitled "KRATON Thermoplastic Rubbers in oil gels," published by the Shell Chemical Company ("Shell Publication") which is hereby incorporated by reference. In the Shell Publication, mixing of Shell Chemical's triblock copolymers, which are marketed under the trade name KRATON.RTM., with oil under heat and shear is disclosed, as well as either increasing the rubber content of the blend or increasing the proportion of rubber segment in the molecule to increase oil retention.
U.S. Pat. Nos. 4,432,607 and 4,492,428, both issued in the name of Alvin C. Levy, both of which are hereby incorporated by reference, disclose oil-extended triblock copolymers (i.e., gels). Those patents describe materials made from styrene block copolymers and a plasticizing agent. The '607 and '428 patents disclose materials which include styrene-ethylene butylene-styrene (SEBS)('607, col. 3, lines 40-41; '428, col. 3, lines 52-53). Specifically, according to the '607 and '428 patents, Levy used KRATON.RTM. G1560 and KRATON.RTM. G1652, both manufactured by Shell Chemical Company of Houston, Tex., as the rubber component of his material ('607, col. 5, line 51; '428, col. 6, line 12). Both patents also state that Shell Chemical's KRATON.RTM. G1651 could be used as the rubber ('607, col. 5, lines 63-66; '428, col. 6, lines 24-27). The copolymers useful in those materials have a styrene to rubber (A:B) ratio of 0.2 to 0.5, and preferably of about 0.4 ('607, col. 2, lines 50-52; '428, col. 2, lines 65-67).
The plasticizer used in the materials of the '607 and '428 patents includes either naphthenic or paraffinic mineral oils or mixtures thereof ('607, col. 2, lines 45-47; '428, col. 2, lines 58-60). Optionally, the plasticizer may contain wax ('607, col. 2, line 60; '428, col. 3, line 8). The '607 and '428 patents state that, in the case of a single-layer or outer-layer coating, microcrystalline wax is preferred as a plasticizer ('607, col. 2, lines 60-62; '428, col. 3, lines 8-10).
In addition, according to the '607 and '428 patents, Levy seems to prefer materials with adhesive characteristics (See '607, col. 7, lines 44-47; '428, col. 8, lines 6-9). For this reason, Levy used resins which associate with the styrene end-blocks of the block copolymer, such as coumarone-indene copolymer or vinyl toluene--.alpha. methyl styrene copolymer, to provide adhesive characteristics to his material ('607, col. 2, lines 55-59; '428, col. 3, lines 3-6).
Both of these patents teach away from the use of high molecular weight rubbers, citing difficulty in blending with other components as the primary problem ('607, col. 5, lines 63-66; '428, col. 6, lines 24-27). Thus, it seems that the materials disclosed therein may have low tensile strength and inadequate elongation. Further, the high-adhesive properties (i.e., tackiness) of the preferred materials of the '607 and '428 patents are not desirable in many gelatinous elastomer (gel) applications.
U.S. Pat. No. 4,497,538, issued in the name of Naren I. Patel, which is hereby incorporated by reference, discloses a composition which includes SEBS block copolymers, petrolatum and polyethylene. According to the examples in the patent, SEBS makes up from 0.5 to 15 percent of the material (Table 1, col. 2, line 60 to col. 3 line 65). SEBS having a styrene to rubber (A:B) ratio of 0.39 to 0.41 is useful for purposes of that patent (col. 2, lines 4-6). Specifically, Patel prefers Shell Chemical's KRATON.RTM. G1650 and G1652 (col. 2, lines 7-10).
According to the examples, the compound of the '538 patent includes 80 to 93.5% petrolatum (Table 1). Petrolatum containing no more than about 15% oil, as determined by ASTM D 721, is preferred (col. 2, lines 12-14). Polyethylene makes up from about 1 to 15% of the material (Table 1). Polyethylenes that are considered useful in that material have a molecular weight in the 1,000 to 10,000 range and a specific gravity of greater than 0.90 (col. 2, lines 28-30).
Patel does not disclose physical properties such as strength or elongation, leading Applicant to suspect that the materials of the '538 patent have both little strength and little elongation. A further problem with the materials of the '538 patent are their low melting temperatures, in the range of 72.degree. C. to 117.degree. C. (Table 1).
The material disclosed in U.S. Pat. No. 4,509,821, issued in the name of Richard J. Stenger, which is hereby incorporated by reference, has a lower viscosity and a higher drip temperature (i.e., the temperature at which a material flows on its own, determined by placing a 20 gram sample in a three inch diameter dish which is positioned vertically within a forced air oven for two hours--drip temperature is often higher than melting point) than many of the prior art materials (col. 2, lines 61-63).
That material includes a plasticizing oil, SEBS and a linear polyethylene wax. The plasticizing oil, which makes up from 85 to 91% of the compound (Figure), is either naphthenic oil, paraffinic oil or a mixture thereof (col. 1, lines 59-64). The SEBS, which makes up from 5 to 10% of the material (Figure), has a styrene to rubber (A:B) ratio of from approximately 0.2 to 0.5, preferably of about 0.4 (col. 1, lines 64-67). Polyethylene wax having an average molecular weight in the range of about 1,000 to 1,500 (col. 1, line 67 to col. 2, line 1) makes up the remaining 2 to 8% of the material (Figure).
Applicant believes the materials of the '821 patent to be weak and have a low percent elongation. Further, the drip temperatures of those materials are relatively low and undesirable (See col. 2, line 55).
U.S. Pat. No. 4,709,982, issued in the name of Robert W. Corne et al., which is hereby incorporated by reference, discloses a gelled oil filling compound which includes a block copolymer having a molecular weight in the 200,000 to 2,000,000 range (col. 2, lines 34-35) and a hydrocarbon oil having an aromatic content of 12% or less (col. 2, lines 25-29). Corne's preferred block copolymer is Shell Chemical's KRATON.RTM. G1651, an SEBS copolymer (col. 3, lines 29-31). That material includes from about 1 to 10% SEBS (col. 2, lines 36-37), depending upon the oil characteristics (col. 3, lines 36-40). However, use of the material of the '982 patent seems to be limited to "gelled oil filling compound[s]" (claim 1).
Nevertheless, due to Corne's preferred use of KRATON.RTM. G1651 in that material, an SEBS triblock copolymer, Applicant believes the Corne compound to have low tensile strength and low percent elongation, just as Chen's material does. Applicant also believes, based upon the preferred copolymer of the '982 patent, that those materials possess undesirably high oil bleed and tack.
U.S. Pat. No. 4,716,183, issued in the name of Jose P. Gamarra et al., which is hereby incorporated by reference, discloses oil-extended styrene-diene block copolymers which include a cross-linked multifunctional coupling agent. In particular, the patent's examples all discuss the use of Shell Chemical's KRATON.RTM. G1650, KRATON.RTM. G1651, or a mixture thereof. The copolymers make up from about 2 to about 30 weight percent of the material, based upon the total weight of the material (col. 2, lines 3-4). The preferred embodiment contains from about 12 to about 22 weight percent block copolymer (col. 3, lines 10-11), and includes a combination of a KRATON.RTM. G1650-like material and a KRATON.RTM. G1651-like material in the range of about 40:60 to 60:40, based on the total copolymer weight (col. 2, lines 43-62). Cross-linking was performed for improved shape retention at higher temperatures (col. 2, lines 23-32). Gamarra et al. claim that cross-linking did not diminish the other physical properties of the material, such as tensile strength and percent elongation. No testing data that would tend to reveal those types of properties was provided for cross-linked materials.
Nevertheless, the non-cross-linked materials disclosed in the '183 patent, the strength of which was not diminished by cross linking, exhibit fairly low tensile strength and low elongation (Table, col. 4, line 57 to col. 5, line 20). Of the published results, the material having the greatest tensile strength and elongation had a 20 weight percent KRATON.RTM. G1651 copolymer component. The tensile strength of that material was only 142 psi, the elongation was only 1810%.
U.S. Pat. No. 4,798,853, issued in the name of Dale L. Handlin, Jr., which is incorporated herein by reference, describes a gel filling composition for cables which includes two to fifteen weight percent SEBS and 85 to 98 weight percent naphthenic or paraffinic oil or solvent having an aromatic content of up to 25 weight percent of the oil/solvent weight, the weight percentages of SEBS and oil being based upon the total composition weight (col. 2, lines 51-61). Most of Handlin's examples utilize Shell Chemical's KRATON.RTM. G1652. Oils/solvents having an aromatic content of about 15% are also preferred (col. 2, lines 60-61).
Applicant believes the materials of the '853 patent to have poor (i.e., low) tensile strength and elongation. Further, many of the materials described in the '853 patent have low gellation and dissolution temperatures, which vary depending upon the SEBS and the oil/solvent. According to the patent's examples, the gellation and dissolution temperatures of materials containing KRATON.RTM. G1652 ranged from about 15.degree. C. to about 60.degree. C. In contrast, a material containing the higher molecular weight KRATON.RTM. G1651 gelled at a temperature greater than 100.degree. C.
Pressure sensitive adhesives are the subject of U.S. Pat. No. 4,833,193, issued in the name of Sieverding. The adhesive materials of that patent contain from about 2 to about 40 weight percent triblock copolymer, alone or in combination with a diblock copolymer (col. 12, lines 8-14), at least 20 weight percent of a low molecular weight resin (col. 12, lines 15-18) and up to about 80 weight percent mineral oil having a viscosity of about 200 to about 1,200 (col. 12, lines 19-21).
Sieverding's preferred triblock copolymers are SEBS copolymers having essentially the same characteristics as KRATON.RTM. G1651 (col. 12, lines 38-40). Sieverding's most preferred high molecular weight SEBS has a styrene to rubber (A:B) ratio of about 0.48 to about 0.52 (i.e., about 48:52 to about 52:48)(col. 12, lines 40-45).
The '193 patent does not disclose the tensile strength of the materials described therein. Despite the possible increase in tensile strength, Applicant believes that the tensile strength of the materials of the '193 patent are low since SEBS is used in those materials.
U.S. Pat. Nos. 4,942,270 and 5,149,736, both issued in the name of Jose P. Gamarra, both of which are incorporated herein by reference, disclose gel compositions for use in cable sealing apparatus which are "nonmeltable" (i.e., begin to degrade, decompose or break down in some manner before they reach a temperature at which the composition will melt and become pourable). The compositions of those patents each include an SEBS triblock copolymer and oil. One of Gamarra's preferred SEBSs has a high molecular weight, particularly in the 250,000 to 280,000 range ('270, col. 4, line 64 to col. 5, line 1; '736, col. 4, lines 39-41), and a styrene to rubber ratio (A:B) of 33:67 ('270, col. 4, lines 46-48; '736, col. 4, lines 13-20). The SEBS sold by Shell Chemical as KRATON.RTM. G1651 was used for the patent's examples. While SEBS amounts of between about 2 and 30 weight percent of the total composition are disclosed, the preferred range is stated as 5 to 25 weight percent ('270, col. 4, lines 13-16; '736, col. 3, lines 51-56).
Oils which are useful in the compositions have molecular weights in the range of about 400 to about 2,500, and preferably in the range of 450 to 1,500 ('270, col. 5, lines 24-29; '736, col. 4, lines 64 to col. 5, line 1). Oil makes up from 70 to 98 weight percent of the composition, preferably from 75 to 95 weight percent ('270, col. 4, line 16; '736, col. 3, lines 50-51, 56). Gamarra prefers that the SEBS and oil are melt blended under high shear ('270, col. 2, lines 53-59, 65-66; '736, col. 2, lines 50-52, 63-64).
Gamarra notes that ultimate elongation of the compositions are from about 200% to about 1,200%. However, the preferred elongation range is about 400 to 1,100% ('270, col. 4, lines 22-26; '736, col. 3, lines 63-66). Such low elongation capability makes these materials undesirable for use in many applications. Further, although the patents do not list values for tensile strength, in light of the relevant SEBS-related prior art, Applicant believes that the materials of the '270 and '736 patents have low tensile strength.
U.S. Pat. No. 5,331,036, issued in the name of Jung W. Kang et al., which is hereby incorporated by reference, describes elastomer compositions which include copolymer compositions of 1,3-conjugated dienes and aromatic vinyl compounds having a weight average molecular weight of greater than about 1,000,000 and oil. Copolymers suitable for use in that material include, among others, midblocks (B) of 1,3-butadiene, 2,3-dimethyl-1,3 butadiene and 1,3 hexadiene (col. 4, lines 1-20). Kang prefers using styrene-butadiene-styrene block copolymers (col. 4, lines 58-60). The oil makes up from about 23 to about 75 weight percent of the composition, preferably greater than about 44 weight percent (col. 2, lines 47-50).
Physical characteristics such as tensile strength, elongation and Young's tensile modulus, durometer and rigidity are not provided by the '036 patent. Nor, to Applicant's knowledge, are the materials disclosed therein commercially available, even since Applicant interview the assignee of the '036 patent regarding those materials. Nevertheless, because of the extremely high molecular weight of the copolymers used in those materials, which is believed to result in entanglement of the rubber midblock, Applicant believes them to have low tensile strength and elasticity and high tensile modulus, high durometer and high rigidity measurements.
A gelatinous elastomeric material is needed which has improved elongation and tensile strength over the prior art, with comparable softness (i.e., durometer). A material is needed which has reduced oil bleed over prior art materials or no oil bleed, and reduced tack. Additionally, an elastomeric material which deforms easily under load and has a high level of shape memory is needed, exemplified by a rebound rate of about one second or less when a one inch long piece of the material is stretched to two inches an released.

Gelatinous elastomer and methods of making and using the same and articles made therefrom


A method enables olefin compound production with a high productivity, and an enzyme is used in the method. Mutations involving amino acid substitution are introduced into various sites of diphosphomevalonate decarboxylase (MVD) to prepare multiple MVD variants. Then, these variants are evaluated in terms of catalytic activity for producing an olefin compound such as isoprene, and have found as a result that the catalytic activity is improved when serine at position 153 and threonine at position 209 are each substituted with a different amino acid. In addition, the catalytic activity of the variants is further improved when glycine at position 152 is further substituted with a different amino acid.

Olefin compounds such as isoprene are very useful as raw materials for various synthetic polymers such as synthetic rubbers. The compounds can be obtained by chemical methods such as fractional distillation of petroleum.
Nevertheless, even by such chemical methods, the yield is low, the production cost is high, and it takes time. Further, in consideration of the recent environmental problems, there are demands for the development of environmentally-friendly and sustainable methods for producing olefin compounds without wasting limited resources, instead of the chemical methods.
In view of such a situation, efforts have been made to produce olefin compounds by utilizing or modifying metabolic pathways of microorganisms and so forth. For example, there have been disclosed methods for producing isoprene and the like by introducing a mutation into a diphosphomevalonate decarboxylase or the like involved in the mevalonate pathway, and thereby utilizing the enzyme variant (PTLs 1 to 3).
Also, it has been attempted by the present inventors to produce isoprene and the like by introducing one or more amino acid mutations in a diphosphomevalonate decarboxylase and changing the substrate specificity of the enzyme (diphosphomevalonate decarboxylase variant) from the original 5-diphosphomevalonic acid to that for 3-hydroxy-3-methylpent-4-enotate or the like.
More specifically, the present inventors introduced mutations involving amino acid substitution into various sites of diphosphomevalonate decarboxylase, and prepared about 200 diphosphomevalonate decarboxylase variants. Then, these variants were evaluated in terms of the catalytic activity for isoprene production.
As a result, the prevent inventors have revealed that, among the many, about 200 variants, a diphosphomevalonate decarboxylase (R74HT209R) in which arginine at position 74 is substituted with histidine and threonine at position 209 is substituted with arginine has by far the highest catalytic activity for isoprene production (NPL 1).

Diphosphomevalonate decarboxylase variant and method for manufacturing olefin compound using same


Using a highly doped Cap layer of the same composition as the Contact material in an nBn or pBp infrared photodetector allows engineering of the energy band diagram to facilitate minority carrier current flow in the contact region and block minority current flow outside the Contact region. The heavily doped Cap layer is disposed on the Barrier between the Contacts but electrically isolated from the Contact material.

Typical designs for an infrared photodetector for a focal plane array comprise a "Barrier" layer of constant alloy composition, whose composition is specifically chosen to guarantee a near-zero valence-band offset in order to obtain high-efficiency collection of photogenerated minority carriers. The prior-art devices are optimized for high-efficiency collection of photogenerated charge in the bulk of the device, but fail to provide mechanisms to minimize the effects of surface recombination/generation in the periphery outside the influence of the semiconductor contact. This is especially critical for devices utilizing small (<25 μm) pixels with reduced junction areas in practical focal-plane arrays. The effect of the surface recombination/generation in the periphery shows up in the dark current.

Infrared photodetector with reticulated contact


A method of manufacturing and testing integrated optical composites in which fiber pigtails are aligned with and attached to the optical output ports of a plurality of integrated optical components on a wafer, prior to separation into individual components. The multiple pigtails are arranged at the ends opposite the wafer, to facilitate optical connections during active alignment and measurement testing.

The present invention relates to a method of manufacturing integrated optical devices and testing their performance. The invention is particularly concerned with the manufacture and testing of integrated optical components which have optical fiber pigtails.
Integrated optical components with fiber pigtails are well known. See, Dohan et al. U.S. Pat. No. 4,765,702, Beguin U.S. Pat. No. 4,933,262 and Dannoux et al. U.S. Pat. No. 4,943,130. These components have been produced using ion exchange techniques. Dannoux et al. U.S. Pat. No. 4,979,970 is directed to a method of manufacturing an integrated optical component comprising, for example, a 2.times.2 optical waveguide proximity coupler, each end of the coupler having two optical fibers (pigtails) attached in optical alignment with two ion-diffused waveguides within a glass substrate. FIGS. 2a and 2b of the present application depict a prior art 1.times.2 splitter/combiner of a similar structure.
Pigtailing is a critical step in the manufacture of such integrated optical components. This step includes both the alignment of the optical fiber waveguide paths with the ion-diffused waveguide paths, and the attachment of the fiber pigtail ends to the component surface. The alignment must be very precise, and the attachment must assure the stability of the alignment during environmental variations (especially temperature fluctuations). Precise alignment is difficult, especially for single mode waveguides, whose core diameters are in the range of 5-10 microns.
As described in Dannoux et al. U.S. Pat. No. 4,979,970, the fiber pigtail ends may be precisely aligned with the optical circuit paths using a micromanipulator, after initial approximate alignment by means of an external jig referenced to the component body (col. 4, lines 20-24 and 41-50). The micromanipulator is typically used in conjunction with optical detection means to provide active alignment--the micromanipulator moves the fiber end back and forth in the vicinity of the component waveguide output port, until the detected optical signal is at a maximum. The precision of the micromanipulator movements is on the order of a tenth of a micron.
Once precise alignment is achieved by means of a micromanipulator, a glue joint is applied to the junction of the fiber and the component surface, and the glue is hardened (for example, by ultraviolet light curing) to attach the fiber pigtail to the component.
Referring to FIGS. 2a and 2b, optical component 30 includes waveguide combiner/splitter 25 separated by transverse exit groove 21 from bare fiber attachment support 22 and coated fiber attachment support 23. Transverse exit groove 21 forms alignment space 20, which provides room for the micromanipulator to hold and move the optical fibers. To carry put active alignment, two micromanipulators may be used simultaneously to align input fiber 27 and first output fiber 28. Once fiber 27 and 28 are thus aligned, their precise alignment is maintained by glue joints 26 and 26a, and the fibers are securely attached to the component by adhesive means 24 and 24a. The operation is repeated for fiber 29. For a 1.times.2 device all three fibers may be aligned and attached simultaneously, depending on the sophistication of the micromanipulators and of the software driving them.
In prior art techniques (see FIGS. 1a-1c), the waveguide paths for numerous components are created simultaneously in a single wafer 5 by photolithographic techniques. Thereafter, the components are grooved (FIG. 1b) and separated (FIG. 1c), and all further operations, such as pigtailing and packaging (assembly), measurement, characterization and testing are performed separately on the individual components.
In the prior art fiber pigtailing process described above there are two separate alignment steps for each passive optical component: 1) initial approximate alignment (on the order of +/-20 microns); and 2) precision alignment (on the order of +/-0.5 micron). This is a costly and time-consuming drawback. The initial approximate alignment requires the most time, as the side surface of the component is often a poor reference point. Once the waveguide output port for one of the fibers on the multi-fiber side of a single device has been precisely located, the other output port or ports on this side of this device can be located without repeating the approximate alignment step. This is because the waveguide paths are very precisely aligned with one another in the photolithographic masking stages of the process (better than 1 micron precision). However, the time-consuming approximate alignment step must be repeated for each new device.
FIGS. 1a, 1b and 1c depict the individual component formation process of the prior art. FIG. 1a depicts an integrated optics wafer 5 in which the waveguide paths have been formed (paths are not shown) for tens to hundreds of individual components. FIG. 1b depicts a wafer after fiber attachment supports 2/3 and 2a/3a and transverse exit grooves 1 and 1a have been formed in the wafer, typically by grinding and typically after the waveguide paths have been formed in the wafer. The wafer is thereafter separated into individual components 10 by conventional methods.
Within a single wafer, there is precise alignment between the waveguide paths of different components, due to the inherent precision of the photolithographic process. However, when the wafer is separated into individual components, this precise alignment is destroyed. It is therefore an object of the present invention to preserve the precise alignment of the initial photolithographic process until the fiber pigtails are securely attached to the integrated optical components.
Other steps in prior art manufacturing processes are also costly and time consuming when carried out separately for each individual component. For example, preparation and handling of individual optical fibers for attachment to numerous individual devices requires numerous separate repetitive operations, such as stripping and fiber end face preparation (reduction of back reflections). This is especially true in the alignment and measurement stages of the manufacturing process, where the fiber ends opposite the component must be separately located in order to inject or detect an optical signal. It is therefore another object of the present invention to perform the manufacturing operations of assembly, packaging and measurement on a large number of components at a time, rather than separately on individual components, obviating the necessity of creating a separate optical location and connection with the free end of each fiber pigtail.
In addition, separate handling of individual components in the early stages of the manufacturing process is also time-consuming and costly. It is therefore an object of the present invention to maintain the compact integrity of the integrated optics wafer as long as possible in the manufacture and testing of integrated optical components.

Method of manufacturing and testing integrated optical components