A measurement operation, such as a calorimetry measurement, is performed using a measurement array and a replaceable passivation membrane (e.g., a parylene membrane). The passivation membrane is used to cover the measurement array to provide temporary electrical and chemical passivation, while still allowing measurement of the parameter of interest (e.g., temperature, in a calorimetry measurement). By only replacing the membrane instead of the entire measurement array between measurement operations, the cost of the measurements can be significantly reduced over conventional methods. The passivation membrane can be mounted on a frame to simplify handling of the membrane.

1. Field of the Invention
The invention relates to the field of calorimetry, and in particular, to a system and method for reducing nanocalorimetry operating costs.
2. Related Art
Calorimetry is used to measure enthalpic changes, including enthalpic changes arising from reactions, phase changes, changes in molecular conformation, temperature variations, and other variations of interest that may occur for a particular specimen. By measuring enthalpic changes over a series of conditions, other thermodynamic variables may be deduced.
For example, measurements of enthalpy as a function of temperature reveal the heat capacity of a specimen, and titrations of reacting components can be used to deduce the binding constant and effective stoichiometry for a reaction. Calorimetry measurements are useful in a broad variety of applications, including, for example, pharmaceuticals (drug discovery, decomposition reactions, crystallization measurements), biology (cell metabolism, drug interactions, fermentation, photosynthesis), catalysts (biological, organic, or inorganic), electrochemical reactions (such as in batteries or fuel cells), and polymer synthesis and characterization, to name a few.
In general, calorimetry measurements can be useful in the discovery and development of new chemicals and materials of many types, as well as in the monitoring of chemical processes. Standard calorimeters require relatively large samples (typically about 0.5 ml to 10 liters) and usually measure one sample at a time. As such, these systems cannot be used to measure very small samples, as might be desired for precious or highly reactive materials. Furthermore, standard calorimeters cannot be used effectively to monitor a large number of reactions of small sample size in parallel, as is required in order to perform studies using combinatorial chemistry techniques.
In recent years, researchers and companies have turned to combinatorial methods and techniques for discovering and developing new compounds, materials, and chemistries. For example, pharmaceutical researchers have turned to combinatorial libraries as sources of new lead compounds for drug discovery. As another example, Symyx Technologies™ is applying combinatorial techniques to materials discovery in the life sciences, chemical, and electronics industries.
Consequently, there is a need for tools that can measure reactions and interactions of large numbers of very small samples in parallel, consistent with the needs of combinatorial discovery techniques. Preferably, users desire that these tools enable inexpensive measurements and minimize contamination and cross-contamination problems.
One of the most popular uses of combinatorial techniques to date has been in pharmaceutical research. Pharmaceutical researchers have turned to combinatorial libraries as sources of new lead compounds for drug discovery. A combinatorial library is a collection of chemical compounds that have been generated, by either chemical synthesis or biological synthesis, by combining a number of chemical "building blocks" as reagents. For example, a combinatorial polypeptide library is formed by combining a set of amino acids in every possible way for a given compound length (i.e., the number of amino acids in a polypeptide compound). Millions of chemical compounds can theoretically be synthesized through such combinatorial mixing of chemical building blocks.
Once a library has been constructed, it must be screened to identify compounds, which possess some kind of biological or pharmacological activity. For example, screening can be done with a specific biological compound, often referred to as a target, that participates in a known biological pathway or is involved in some regulation function. The library compounds that are found to react with the targets are candidates for affecting the biological activity of the target, and hence a candidate for a therapeutic agent.
Through the years, the pharmaceutical industry has increasingly relied on high throughput screening (HTS) of libraries of chemical compounds to find drug candidates. HTS describes a method where many discrete compounds are tested in parallel so that large numbers of test compounds are screened for biological activity simultaneously or nearly simultaneously. Currently, the most widely established techniques utilize 96-well microtitre plates. In this format, 96 independent tests are performed simultaneously on a single 8 cm by 12 cm plastic plate that contains 96 reaction wells. These wells typically require assay volumes that range from 50 to 500 microliters. In addition to the plates, many instruments, materials, pipettors, robotics, plate washers and plate readers are commercially available to fit the 96-well format to a wide range of homogeneous and heterogeneous assays. To achieve faster testing, the industry is evolving to plates that contain 384 and 1536 wells.
A variety of measurement approaches has been used to screen combinatorial libraries for lead compounds, one of which is the inhibitor assay. In the inhibitor assay, a marker ligand, often the natural ligand in a biological pathway, is identified that will bind well with the target protein molecule. The assay requires the chemical attachment of a fluorescent molecule to this marker ligand such that the fluorescent molecule does not affect the manner in which the marker ligand reacts with the target protein. To operate an inhibitor assay, the target protein is exposed to the test ligands in microtitre wells. After a time necessary for reaction of the test ligand to the target protein, the marker ligand is applied. After a time for reaction with the marker ligand, the wells are rinsed such that non-reacted marker ligand is washed away. In wells where the target protein and the test ligand have reacted, the test ligand blocks the active site of the target protein so the marker ligand cannot react and is washed away, while in cells where the target protein and test ligand have not reacted, the marker ligand reacts with the target protein and is not washed away. By investigating the wells for the presence of fluorescence after the washing, reactions of test ligands and target proteins can be determined as having occurred in wells where no fluorescence is observable.
However, the inhibitor assay requires time and expense to develop the assay. The principal components that need development are discovering a marker ligand and attaching a fluorophore to the marker in a manner that does not affect its reaction with the target protein. Attaching the fluorescent marker can often take 3 months of development or more and cost $250 k or more once the marker ligand is identified. An assay method that avoids such assay development, such as measuring the heat of the reaction with calorimetry, would eliminate this cost and lime delay in the discovery process.
Calorimetry measurements are commonly utilized in biophysical and biochemical studies to determine energy changes as indications of biochemical reactions in a media. Prior techniques for measurements include using electrodes, thermopiles, optical techniques, and microcalorimeters for measurements within a sampled media. There is a great interest in developing calorimetry devices, and in particular, ultra-miniature microcalorimeter devices (i.e., nanocalorimetry devices), that require very small volumes of sampled media and that can quickly measure large numbers of reactions. Ideally, those reaction measurements can provide efficient assays; e.g., inhibitor assays which can be used in HTS to screen roughly 100,000 test ligands a day.
Accordingly modern calorimetry tools (in particular, microcalorimetry and nanocalorimetry tools) include an array of detectors that allow multiple measurement operations to be performed simultaneously. FIG. 1A shows a top view of a nanocalorimeter array 100, which is similar to nanocalorimeter arrays described in detail in co-owned, co-pending U.S. Patent Application Serial No. 2003/0186453, herein incorporated by reference.
Nanocalorimeter array 100 includes a frame 110 and two detectors 120. Detectors 120 are commonly amorphous silicon (a-Si) structures that are formed on a Kapton™ plastic film (shown in FIG. 1B), which in turn is supported by frame 110. Detectors 120 include the devices necessary to perform calorimetry measurements on sample droplets 190 of test material. The measurement data is then read out from detectors 120 via contacts 111 on the periphery of frame 110.
In addition, microcalorimeter and nanocalorimeter arrays, such as nanocalorimeter array 100, typically include a thin (1-3 μm) parylene coating 130 that is deposited over detectors 120 (and frame 110). Sample droplets 190 are placed directly onto parylene coating 130, which provides a hydrophobic surface that facilitates the merging and mixing of sample droplets 190. Parylene coating 130 also provides electrical and chemical passivation for detectors 120, while still allowing the thermal effects of droplet interactions to be measured by detectors 120.
The coverage provided by parylene coating 130 is more clearly depicted in FIG. 1B, which shows a cross section of nanocalorimeter array 100. As described above with respect to FIG. 1A, parylene coating 130 covers detectors 130, which in turn are formed on Kapton™ layer 131 (copper strips 132 beneath detectors 130 are isothermal elements to ensure that the measurement elements of detectors 120 are thermally coupled to sample droplets 190).
To avoid contamination, nanocalorimeter arrays (such as nanocalorimeter array 100) are typically discarded after a single use, which can add significant costs to large nanocalorimetry experiments. While parylene coating 130 can sometimes be cleaned and sterilized to enable re-use of nanocalorimeter array 100, such refurbishment activity can be time-consuming and expensive.
Accordingly, it is desirable to provide a system and method for performing calorimetry operations that enables reuse of calorimeter arrays.

Replaceable parylene membranes for nanocalorimeter


A topology independent storage array. In a preferred embodiment the topology of the array is reconfigurable due to information control packets passed among storage nodes comprising the array. The topology of the array, as determine by the relationship between data sets stored within the array's storage nodes and storage maps of the storage node, can be reconfigured without requiring a complete duplication of the entire array. In especially preferred embodiments, the topology of the storage array follows a Z-10 or a Z-110 configuration where storage devices store one or more mirrored parts of a data set per storage device.

Throughout the history of data storage the size of a storage solution has grown. Computers first stored data at the byte level, then at the disk level. The capacity of disks has grown from hundreds of kilobytes to megabytes to gigabytes and will continue grow. As computing environments have grown, so has the environment's demand for yet larger storage solutions. At each stage of growth the atomic unit of the storage solution has also grown from individual disks to multiple disks to complete systems comprising storage farms that include large arrays of numerous disks.
In the world of data storage, RAID stands for "Redundant Array of Inexpensive Disks." Nothing could be further from the truth due the high cost to implement a traditional RAID storage array that meets criteria for a solid solution. Each storage array comprises a set of array parameters that fits the desired criteria where array parameters include metrics based on cost, reliability, performance, capacity, availability, scalability, or other values important to a customer. Typically RAID systems require specialized hardware including SCSI disks, iSCSI equipment, or Fibre Channel switches forcing consumers to pay a large premium to achieve their desired criteria for a solution. High costs place storage array solutions well beyond the reach of consumers and small to medium businesses (SMB). Enterprises, where reliability or performance far out weigh cost, can afford an effective solution.
RAID systems and their associated hardware offer customers a very coarse grained approach to storage solutions. Each RAID level, RAID-0, 1, 0+1, 10, 5, 53, and so on, offers one specific configuration of disks handled by a controller or complex software. Such coarse grained approaches map data to physical locations via a storage map at the disk level or worse yet at the system level. Consequently, these systems have a single fixed topology as defined by their storage maps which govern how data sets contained on the array's disks relate to each other. In addition, each system has a specific set of storage array parameters associated with them. For example, RAID-0 striping offers performance determined by the number of disks in the array but does not offer improved reliability through redundant data. RAID-1 offers reliability through data redundancy on multiple disks but does not offer performance gains. This list continues for each RAID level. Once customers deploy a RAID system, they suffer a great deal of pain migrating to a new system that more closely matches their criteria for a solution. Customers have no easy method of altering an array's parameters to fine tune their solution after the array has been deployed.
Storage systems with a fixed topology, coarse grained storage maps, and specific array parameters force customers to decide a priori exactly what their desired criteria are for a solution. Once the customer determines the criteria for an array's parameters the customer must purchase a storage solution that best matches the criteria, forcing the customer to purchase "up to" the RAID level that best fits the solution criteria and hope that it fits any future needs as well. So, the array cost is high because customers must pursue fixed topology solutions at the system level where controllers govern the system rather than at a fine grained level. If customers had fine grained control over their storage solutions, they would manage their costs more effectively and attain greater coverage of their desired storage solution space.
Clearly, customers need a more malleable storage solution where the customer adjusts the array parameters to more closely fit an application's exact needs as those needs are understood or change. Furthermore, the solution should offer customers the ability to adjust an existing solution without requiring replacement of the system or replicating the entire system. Therefore, an improved storage array should have the following characteristics:                The storage array should be topology independent allowing the array to change over time without concern for changes in the topology        The storage array should offer adjustable reliability, performance, capacity, cost per unit storage, or availability        The storage array should scale naturally at or below the disk level, lowering the atomic unit of a storage solution to the smallest identifiable granularity        The storage array's storage maps should offer fine grained control of data storage at or below the disk level without aggregation of atomic storage units into larger structures        The physical location of data within the array should be dynamic allowing data to migrate from one physical location to another in a manner transparent to operating systems, file systems, or applications
A number of attempts have been made in the past to offer such a solution by combining various RAID levels. Unfortunately, all the attempts have failed to fully provide a cost-effective solution to customers while maintaining reliability, performance, or availability. All existing solutions suffer from scalability issues and have coarse grained storage maps at the system level.
Intel offers a Matrix RAID system where two disks are deployed within a server. The Matrix RAID offers a topology where each disk has one striped partition and one mirrored partition. The mirrored partition on a first disk mirrors the striped partition on a second disk. Through this topology the Matrix RAID system offers double the performance of a single disk system because data stripes across two disks and performs I/O operations in parallel, to within limits of the disk interface. In addition, data is reliable because the data is mirrored providing redundancy should one disk fail. The Matrix RAID is very similar to a RAID-10 system where the capacity of the system is one half of the total disk space; however, data is mirrored advantageously at a partition level rather than a disk level. Although the Matrix RAID system has a number of benefits from a reliability and performance perspective, it suffers from other limitations. The topology is fixed which means a customer cannot alter the array configuration once the customer deploys the system. The system does not scale because the Matrix RAID requires specific BIOS hardware and chipsets to realize the system and is further limited to two disks. Customers of the Matrix RAID are not able to fine tune the system to fit their exact needs after the system is deployed without great effort or cost.
InoStor Corporation's RAIDn system as outlined in a U.S. Pat. No. 6,557,123 follows a more traditional RAID route. Disks are combined together to create a storage array and the customer selects a desired reliability as defined by a number of disks in the array that can fail without the array suffering data loss. Data stripes across the disks in the array similar to a RAID-5 system along with multiple parity stripes. The number of parity stripes and their arrangement in the array is determined mathematically once the customer selects a desired reliability. InoStor's solution provides a blend of reliability and performance; however, the system suffers from scalability issues because specialized hardware is required to manage and calculate a complex parity. If a customer wishes to increase the capacity of the system, the customer must purchase an additional array. Consequently, InoStor's solution also suffers from the same limitations of a fixed topology as other RAID systems, namely the array cannot adjust easily once deployed.
Unisys Corporation's U.S. Pat. No. 6,785,788 outlines another attempt at offering a flexible storage array. Unisys forgoes parity in favor of mirroring just as the Intel Matrix RAID with the exception data stripes across disks of first capacity then the data mirrors across disks of a second capacity. This topology, also fixed, offers the advantages of performance and further offers customers the ability to purchase disks of disparate sizes thereby offering a more economical solution. However, because the data is still bound to complete disks, the system does not upgrade easily. In addition, the system does not scale naturally at the disk level.
Earlier prior art solutions fall short of offering a truly advantageous solution because they are bound to fixed topologies governed by expensive centralized hardware or complex software with coarse grain storage maps. A virtualized approach where data decouples from physical locations allows for the creation of arrays with flexible topologies governed by reconfigurable policies. Topologies based on nodes that map to logical partitions at or below the disk level rather than nodes that map to disks have the greatest flexibility. If data is decoupled from physical location, then data can move from one physical location to another transparently from the view of clients using the array. Furthermore, each client stores a different storage map thereby "seeing" a different array even though the physical storage system is shared among a number of clients. Topology independent arrays have reduced costs because each element in the system behaves independently eliminating the need for complex centralized governing systems and allows for expansion at the single disk level. Through an appropriate choice of a topological configuration, reliability of a storage array exceeds RAID-10, RAID-5, and even RAID-6 systems. Even though a topology independent array can employ RAID concepts including parity, employing redundancy for reliability offers greater performance at reduced cost because parity does not need to be maintained with specialized hardware. High performance is a natural result of a desired policy that incorporates data striping and scales as desired even after deployment by adding disks. Capacity also scales naturally at the disk level by adding disks to the array. Customers are always able to purchase disks that have the highest capacity-price (or performance-price) ratio. Data availability remains high because data can be mirrored for redundancy or data can move from an un-reliable location to a more reliable location in a manner that is transparent to applications. Customers also have the ability to trade one array parameter for another. For example, when establishing the policy for a topology independent storage array, by increase the reliability of an array via adding additional mirroring the available capacity of the array is reduced in response to the change assuming a fixed number of disks in the array.
Thus, there remains a considerable need for methods and apparatus that allow fine grained control of a storage array without requiring customers to spend a great deal of money to achieve their desired reliability, performance, capacity, scalability, or availability criteria.

Topology independent storage arrays and methods


Exemplary systems, devices, methods, apparatus and computer-accessible media for providing and/or utilizing optical frequency domain imaging (OFDI) and fluorescence of structures and, e.g., multimodality imaging using OFDI techniques and fluorescence imaging techniques are described. For example, an arrangement can provide at least one electro-magnetic radiation to an anatomical structure. Such exemplary arrangement can include at least one optical core and at least one cladding at least partially surrounding the fiber(s). A region between the optical core(s) and the cladding(s) can have an index that is different from indexes of the optical core(s) and the cladding(s). The arrangement can also include at least one apparatus which is configured to transmit the radiation(s) via the optical core(s) and the cladding(s) to the anatomical structure.

A majority of diseases arise within luminal organs such as the gastrointestinal tract and coronary arteries. Understanding and diagnosis of these diseases can require knowledge of their gross and microscopic structure, as well as their composition and molecular and cellular expression.
An optical imaging catheter has become an important tool to assess and diagnose diseases arising from luminal organs. This is the case, since many of the mechanisms involving diseases occur on a microscopic scale, high-resolution imaging techniques can be very important. Thus, optical imaging techniques, which are also considered to be relatively safe and non-toxic, are can be used for in vivo imaging. Optical frequency domain imaging (OFDI) or optical coherence tomography (OCT) imaging using rotationally scanning catheters can be used for studying cross-sectional and three-dimensional microstructure of luminal tissues. However, information such as molecular expression and tissue composition may not be ascertained from the OFDI signal. Other independently developed catheter-based imaging modalities, such as Raman spectroscopy, fluorescence imaging, near-infrared fluorescence (NIRF), time-resolved lifetime spectroscopy (TRLIFS), and near-infrared spectroscopy (NIRS) can provide this additional information. However, these exemplary techniques operate without knowledge of the underlying microscopic structure, making it difficult to place the acquired signatures in the appropriate morphologic context.
In order to resolve such possible issues and advance catheter-based diagnosis, it is therefore possible to obtain OFDI images in combination with data from these complementary modalities. Multimodality imaging techniques have been developed for cellular imaging under a microscope or small animal imaging due to relatively easy accessibility. However, in vivo multimodality imaging of luminal organs, such as coronary arteries, gastrointestinal tract, and respiratory system has not been appropriately described. Although multimodality imaging techniques in a catheter form have been utilized, such techniques could not provide comprehensive three-dimensional (3D) information from the luminal organs yet, due to the lack of fast rotation, high speed acquisition, and/or small catheter for in vivo data collection.
A sequential acquisition of such diverse information using multiple independent catheters and systems has, however, likely been untenable due to the impracticality of conducting multiple procedures, subject motion, and difficulties registering datasets. Thus, there may be a need to provide combined multimodality OFDI catheters and systems which can facilitate, e.g., a simultaneous acquisition of co-registered OFDI and complementary structural, compositional, and/or molecular data. In addition, it may be beneficial to address and/or overcome at least some of the deficiencies of the prior approaches, procedures and/or systems that have been described herein above.

Systems, devices, methods, apparatus and computer-accessible media for providing optical imaging of structures and compositions


An LED unit includes an LED and an envelope receiving the LED therein. The envelope includes a bottom substrate fixing the LED thereon, a sidewall angling upwardly from the substrate and surrounding the LED, and a lens formed in the sidewall and located above the LED. The lens has two aspheric surfaces with different curvatures to collect light deflected at a small angle relative to an axis of the LED into a parallel pattern. The sidewall has upper and lower conical inner circumferences and a parabolic outer circumference to direct light deflected at a large angle relative to the axis of the LED into parallel pattern. The lower inner circumference of the sidewall has an angle of 2π/5 to 13π/30, and the upper inner circumference of the sidewall has an angle of 5π/36 to 7π/36.

1. Field of the Invention
The present disclosure relates to light emitting diode (LED) units and, more particularly, to an LED unit comprising a lens having two aspheric surfaces.
2. Description of Related Art
LEDs, available since the early 1960's, have been increasingly used in a variety of applications, such as residential, traffic, commercial, and industrial settings, because of high light-emitting efficiency. A typical LED includes an LED die emitting light and a transparent encapsulant enveloping the LED die. The encapsulant protects the LED die from contamination and damage, and acts as a lens. However, due to size limitations of the encapsulant, the light cannot be significantly converged. The divergent light results in limited brightness of the LED. Therefore, light-adjusting devices, such as a catadioptric light distribution system, are utilized for further collimation of the light from the LED.
A typical catadioptric light distribution system includes a reflector mounted below and surrounding the LED, and a convex lens mounted above the LED. The reflector reflects light toward the lens from a perimeter of the encapsulant. The lens consolidates light emitted from the LED and reflected by the reflector into a single beam. Using the catadioptric light distribution system, most of the light emitted from the LED can be converged, and the brightness of the LED is increased.
However, since the lens of the catadioptric light distribution system is often spherical, the lens cannot effectively culminate the light into a narrow beam. The light incident on an opposite surface of the lens, after passing through the spherical surface of the lens, is still divergent, resulting in a scattered light beam, oriented away from the lens, and thus unsuitable for long-distance illumination.
What is needed, therefore, is an LED unit which can overcome the limitations described.

Fu Zhun Precision Industry (Shen Zhen) Co., Ltd.


Amplifying signals includes receiving an input signal. The input signal is amplified at a quadrature coupled amplifier to generate an amplified signal. The input signal is compared with the amplified signal to generate an error signal. The error signal is amplified at the quadrature coupled amplifier to generate an amplified error signal. The amplified error signal is compared with the amplified signal to generate an output signal.

Feedforward amplifiers may be used in communication systems to amplify signals while reducing non-linearity effects. In known feedforward amplifiers, an input signal is amplified by a power amplifier to yield a high power output signal. The amplified signal is compared with the input signal to generate an error signal. The error signal may be amplified to compensate for combining losses. The error signal is combined with the high power output signal in order to reduce the non-linearity effect of the power amplifier. Known feedforward amplifiers, however, are typically inefficient. It is generally desirable to have efficient feedforward amplifiers.

Amplifying signals using a quadrature coupled amplifier


A handle for an electronic instrument housing includes an elongated grip portion. The grip portion includes two elongated elements each having opposed ends. The elements are connected to each other to form an elongated chamber. An elastomeric layer encompasses an intermediate portion of the grip portion, and the grip portion has a vent aperture communicating with the chamber. The vent aperture may be beyond the elastomeric layer, at one or both ends. One of the elongated elements may form a channel with tapered edge surfaces receiving the other element, so that pressure of elastomeric molding tends to wedge the parts together to form a seal against incursion of the elastomer.

Carry handles for electronic instruments are normally desired to be lightweight, relatively rigid, and comfortable. A typical handle has an elongated grip with a hollow tube providing structural support, and an overmolded elastomeric coating for user comfort. The cores of such hollow handles may be formed by gas assist molding, in which air is introduced into the plastic molding process to provide a hollow chamber. While effective, gas assist molding has the disadvantage of being relatively expensive compared to conventional injection molding. In addition, the process is too sophisticated for many manufacturers, limiting the available sources for such parts.
An alternative to gas assist molding for forming hollow parts is to form such parts in two pieces, and assemble them to provide a hollow part. This is feasible in some applications. However, multi-part construction is normally not suitable for parts that require overmolding with an elastomeric layer. The overmolding process involves placing the molded handle into a larger mold, and injecting elastomer into the void between the handle and the mold to provide a conforming elastomer layer. The pressures involved in the overmolding process may crush the core part if it lacks sufficient structural integrity, and any gaps between the components can allow an unwanted incursion of elastomer into the hollow chamber. Moreover, even if the core is adequately sealed against incursion of elastomer, even minimal gaps or seams allow pressurized gas to get trapped inside the part during overmolding process. This pressurized gas then can cause bubbling or delamination of the overmolded material when the part is released from the pressure of the mold, as the gas attempts to expand.

Molded instrument handle and method of manufacturing


There is provided a material comprising a multi-block thermogelling polymer, said multi-block thermogelling polymer comprising a hydrophilic polymer block; a thermosensitive polymer block; and a hydrophobic polymer block, wherein the hydrophilic polymer block, the thermosensitive polymer block and the hydrophobic polymer block are chemically coupled together by at least one of urethane/carbamate, carbonate, ester linkages or combinations thereof, and wherein the material is suitable for use as a vitreous substitute. Also provided are a method of preparing said material and a synthetic vitreous humour or part thereof comprising said material.

The vitreous is a clear, gelatinous substance occupying the vitreous cavity. Composed of 98-99 wt % water, the vitreous is a natural polymeric hydrogel constituted primarily of collagen fibers and hyaluronic acid. In addition to the maintenance of normal orbit turgor to position the retina, the vitreous has important physiological functions in the circulation of metabolites and nutrients. Ageing and vitreous degeneration increase the liquefaction of the vitreous, which may result in increased vitreo-retinal traction and cause sight-threatening conditions such as retinal detachment.
Retinal detachment is the fifth leading cause of blindness in developing countries. During retinal detachment repair, vitrectomy surgery (whereby vitreous is removed from the eye) is performed to relieve vitreous traction. As the vitreous humor cannot regenerate de novo, the cavity must be filled with a substitute during and after surgery. Ideally, this substitute should closely resemble native vitreous in both structure and function. Post-surgery, it has to act as an endotamponade agent to facilitate re-adhesion of the detached neurosensory retina to the underlying retinal pigment epithelium. However, the search for a suitable vitreous substitute remains challenging. Indeed, current substitutes used have several limitations and are far from desirable. This is further elaborated below.
In current clinical practice, materials used include perfluoro-carbon liquids that are used as temporary intra-operative tamponade, and expansile gases and silicone oil that are used for medium and long-term tamponade, respectively. However, there are multiple disadvantages related to their usage, as summarised in Table 1. For example, gaseous substitutes need face-down positioning for several weeks post-surgery (due to buoyancy forces) and patients are unable to travel by air. Silicone oil substitutes require additional removal surgery with potential complications, including raised intra-ocular pressure, temporary loss of vision, cataract formation and long-term retinal toxicity.
TABLE 1A summary of the limitations of current vitreous tamponadesAvailable VitreousPhysicalRemarksSubstitutesStatusAdvantagesDisadvantagesAirGasHigh surfaceShort residence timetension(few days)SF6/C3F8GasHigh success rateSudden increase in(~90% forintraocular pressure, cataractretinopexy)formationSuitable for short-Prolonged, face-downterm vitreouspositioning post-operativelysubstitutesfor up to 4 weeksUnable to travel by air/divingLess effective for inferiorretinal detachment (RD)BalancedLiquidSimilar in density,Temporary substituteSaltrefractive index andNo tamponade effect due toSolutiontransparency tolow surface tension(BSS)vitreousPerfluorocarbonLiquidHigh specificTemporary substituteLiquidgravity, clear,For intra-operative usage(PFCL, PFDcolorless andonlyand PFO)odorlessRequire complete removalRetinal toxicity, intraocularinflammatory reactions ifretainedSiOLiquidSimilar refractiveNon-biodegradableindex to vitreousRequires a second surgeryCurrent goldfor removalstandard for long-Cataract induction, cornealterm tamponadetoxicity (band-K), glaucoma,(6 months)macular oedema and"silicone retinopathy"
While many materials have been proposed and tested, an ideal vitreous substitute remains elusive.
Although polymeric hydrogels such as currently available hydrogels (including gelatin, poly(1-vinyl-2-pyrrolidinone), polyvinylalcohol (PVA), polyacrylamide (PAA), tetra-arm poly(ethylene glycol) (Tetra-PEG)), cross-linked hyaluronic acid or self-assembling peptide gels are potential vitreous substitutes because they resemble natural vitreous humor, there are several limitations that prevent their usage as vitreous tamponade. Their limitations include (i) the inability of preformed polymeric hydrogels to maintain their tensile strength after injection through small bore needles, (ii) rapid biodegradability (i.e. short residence time), which prevents formation of chorio-retinal adhesions around retinal tears, and (iii) poor biocompatibility leading to severe intraocular inflammation and long-term toxicity. Often, their ability to exert sufficient surface tension across retinal breaks has either not been assessed or has been found lacking. For example, some commercially available hydrogels have shown that they tend to drift under the retinal tear, resulting in re-detachment of the retina.
In view of the above, there is a need to address or at least ameliorate the above-mentioned problems. In particular, there is a need for a material that is suitable for use as a vitreous humour substitute, a method of making the material and a synthetic vitreous humour that address or at least ameliorate the above-mentioned problems.

Material suitable for use as a vitreous substitute and related methods

Agency for Science, Technology and Research

National University Hospital (Singapore) Pte Ltd


Some embodiments of the teachings herein include a computer-implemented method for automatic derivation of attributes of software engineering artifacts arising from technical boundary condition of product or service development segments comprise: deducing technical requirements using an automated software-based process based on classifications of the technical boundary conditions; mapping the deduced technical requirements of the artifacts to engineering disciplines and concerns using an automated software-based process; mapping the calculated engineering artifacts to responsibilities; adapting the classification of the technical boundary conditions based on the evaluation results in iterations; and processing an executable performing a distribution calculation of the classification space, wherein the distribution calculation of the classification space is at least based on a distribution and quartiles. The process of the executable comprises: calculating combination vectors at system start; reading mapping data and calculation probabilistic distribution and quartiles; and publishing new distribution to engineering goal calculation.

To achieve a certain product or service quality, artifact quality must be aligned across a variety of engineering disciplines, especially software engineering disciplines depending on the underlying task or challenge. Unaligned artifact quality creates quality deficits. Up to now, no technical solution is provided to this sort of problem. Organizational or non-technical procedures are applied sometimes to create consistent attributes for software engineering artifacts, meaning engineering goals, but usually fail to create alignment especially for fairly complex systems or frequent changes in the development task. With any up-to-date distributed methods or systems on a plurality of processes and/or subsystems respectively, any system interruption impedes a continuous workflow.

Automatic derivation of software engineering artifact attributes with integrated distribution calculation


A thin film magnetic recording disk that has a layer of lubricant bonded thereto is enclosed within a vapor phase lubricant system that operates to continuously apply lubricant vapors to the disk's bonded lubricant layer by operation of Langmuir kinetics. Lubricant vapors are selectively adsorbed on the disk, including regions of the disk where the bonded lubricant is either too thin or is entirely absent, thus minimizing failures that might be caused by such imperfections in the bonded lubricant layer. A reactive perfluoropolyether (PFPE) lubricant containing chemically active functional groups is substantially bonded onto the recording surface of the disk, for example by the application of heat. The mobile residue of this bonded lubricant layer may be left on the disk, to thereafter function as a non-bonded, mobile, lubricant layer covering the surface of the bonded lubricant layer. Alternately, the lubricant residue may be substantially removed by use of a solvent or other means, and a nonreactive lubricant, such as a nonreactive PFPE, may thereafter be topically applied onto the surface of the bonded lubricant layer, to function as a non-bonded, mobile, lubricant layer. A lubricant reservoir within the vapor phase lubricant system provides a supply of a volatile organic lubricant, such as stearic acid or reactive or a nonreactive PFPE. Lubricant vapors from this reservoir operate so as to continuously repair voids or thin areas in the disk's simplex layer of substantially bonded lubricant, or in the disk's duplex layer of bonded and mobile lubricant. Either one, two or three lubricants could be used in this tribological system.

A critical feature of rigid, magnetic data, disk storage devices is vulnerability to failure of the storage device as a result of the read/write transducing head slider wearing into the magnetic layer that is located on the disk's surface. Magnetic data storage improvements have been achieved by using a thin film magnetic coating, for example, in the range of about 25 nanometers thick, and by using a low head flying height, for example in the range of about 5 micro inches. Both of these factors require the tribology of the disk to be excellent in order for a useful lifetime to be achieved for the storage device. Generally, a thin film of lubricant molecules is required as part of the disk's tribological system. This lubricant film provides a low coefficient of friction when the head slider lands on the disk, for example as part of a start/stop operation, or when the head slider intermittently hits the disk while flying relative thereto.
As a result, the use of lubricants on the recording surface(s) of a magnetic recording disk is well known in the art. Generally, these lubricants are supplied as thin layers, for example from one to many monomolecular layers thick.
In the art of rigid, thin film memory disks, a lubricant is conventionally used to reduce friction, to prevent head stiction in the start/stop (S/S) area of the disk, and to provide a debris-free flying interface for the disk and its read/write transducing head.
Fluorocarbon lubricants are commonly used in a rotating rigid disk direct access storage device (DASD). These lubricants possess the desirable properties of chemical inertness, low surface tension, low volatility, and in addition these lubricants can be moisture repellant and can retard corrosion. However, these lubricants have a disadvantage in that they tend to centrifugally migrate to the outer edge of the disk, due to the force of disk rotation. This lubricant migration can lead to increased interference at the head/disk interface, and may eventually lead to complete failure of the interface.
The above mentioned related inventions describe disk lubrication systems wherein a reservoir contains a volatile organic lubricant. This volatile lubricant operates to continuously supply lubricant vapors to the recording surface of a magnetic recording disk.
Another approach to disk lubrication is to chemically bond a single, or simplex, layer of lubricant molecules to the disk's recording surface. In this case the lubricant is immobilized due to strong physical adsorption or weak pseudo-molecular bonding of the lubricant to the underlying disk surface. As a result, the lubricant does not appreciably evaporate from the recording surface over an extended period of use, nor does the lubricant gradually spin off of the disk surface as a function of the disk's high speed of rotation. Examples of such bonded lubricants are perfluoropolyethers (PFPE) having various hydrocarbon functional groups. The functional groups of these perfluoropolyether lubricants are active in bonding the lubricant molecules to the disk's recording surface. A sputtered carbon overcoat layer typically provides an active overcoat surface on the thin film magnetic layer, to which overcoat surface the lubricant is bonded. Other sputtered overcoat layers are also used. In this arrangement, after the lubricant is topically applied to the overcoat layer, the lubricant is bonded thereto by the application of heat, E-beam or by another source of irradiation that effects bonding of the lubricant molecules to the magnetic recording layer, or to the overcoat layer when one is used.
In this type of a bonded lubricant system, we have observed that the bonded lubricant layer usually does not provide uniform coverage of the disk's overcoat or thin film magnetic recording layer. Voids or thin areas tend to occur in the layer of bonded lubricant. This lack of integrity in the bonded lubricant layer may occur as a result of natural defects that occur during the bonding process or manufacturing process, or this lack of layer integrity may result from wear to the disk's surface during data processing.
Duplex layer, i.e. two layer, lubricant coatings on the magnetic recording layer of magnetic recording media is known in the art.
Such a duplex lubricant system can be formed subsequent to providing the above mentioned bonded lubricant layer, in which case it is customary to either leave the residual unbonded lubricant on the disk surface, to thereafter function as a second, mobile, lubricant layer, or the residual lubricant may be washed off after the bonding step, and a second unbonded lubricant layer may be topically applied, to thereby form a duplex lubricant coating on the disk. However, even such a duplex lubricant system is likely to develop nonuniform lubricant coverage (i.e. voids and/or thin areas).
The publication IEEE Transactions on Magnetics, Vol. MAG-23, No. 1, January 1987, at pages 33-35 describes the use of duplex fluorocarbon films, one film being chemically and permanently bonded to the media surface, and the other film being a lubricant that is overcoated onto the primed disk surface. The top lubricant is said to have the properties typical of a liquid lubricant.
UK Patent Application GB 2,155,810 A describes a magnetic recording medium comprising a non-magnetic substrate, a magnetic recording ferromagnetic film on one side of the substrate, and a topcoat layer formed on the surface of the recording layer, the topcoat layer comprising a radiation curable antioxidant and a lubricant.
U.S. Pat. No. 4,642,246 describes a process for lubricating a magnetic disk comprising contacting the disk with a functionalized lubricant having at least one functional terminal group, heating the lubricant so as to bond the functional terminal group to the surface of the disk, and then contacting the disk with a non-functionalized lubricant.
U.S. Pat. No. 4,713,287 describes a magnetic recording medium comprising a support having a thin magnetic film thereon, a thin layer of a fluorinated polymer on the magnetic film, and a lubricating agent coated on the polymer layer.
As stated previously, the above mentioned related inventions describe lubricant reservoir systems that operate to continuously supply lubricant vapors to magnetic recording disks by way of Langmuir adsorption kinetics.
While prior disk lubrication systems have been generally acceptable, as the data handling requirements of thin film magnetic recording disks increase, it is desirable that lubrication of the disks also be improved.

Direct access storage device with vapor phase lubricant system and a magnetic disk having a protective layer and immobile physically bonded lubricant layer

International Business Machines Corporation


The present invention is directed to a golf ball comprising a core and a cover, wherein the cover comprises a blend of two or more high acid ionomer resins. Each high acid ionomer resin utilized in the blend of the cover composition comprises generally of greater than 16% by weight acid, preferably from about 17 to about 25% by weight acid and more preferably from about 18.5% to about 21.5% by weight acid. The acid groups of the high acid ionomers utilized in the cover compositions of the invention are partially (i.e. generally 10-75 percent, preferably 30-70 percent) neutralized by metal ions such as by sodium, zinc and magnesium ions. When the blend of two or more high acid ionomer resins is utilized to manufacture a golf ball, the golf ball produced thereby, exhibits properties of improved distance without sacrificing characteristics such as playability and/or durability when compared to low acid ionomer and/or low acid/high acid ionomer blends.

The present invention relates to golf balls and, more particularly, to improved golf ball covers made from blends of specific high acid ionomers. The improved golf ball covers are useful for producing golf balls, particularly multi-piece balls, exhibiting enhanced travel distance while maintaining the playability and/or durability characteristics necessary for repetitive play.
Ionomeric resins are polymers containing interchain ionic bonding. As a result of their toughness, durability, and flight characteristics, various ionomeric resins sold by E. I. DuPont de Nemours and Company under the trademark xe2x80x9cSurlyn(copyright)xe2x80x9d and more recently, by the Exxon Corporation (see U.S. Pat. No. 4,911,451) under the trademarks xe2x80x9cEscor(copyright)xe2x80x9d and the tradename xe2x80x9cIotekxe2x80x9d, have become the materials of choice for the construction of golf ball covers over the traditional xe2x80x9cbalataxe2x80x9d (trans polyisoprene, natural or synthetic) rubbers. The softer balata covers, although exhibiting enhanced playability properties, lack the durability properties required for repetitive play.
Ionomeric resins are generally ionic copolymers of an olefin, such as ethylene, and a metal salt of an unsaturated carboxylic acid, such as acrylic acid, methacrylic acid or maleic acid. In some instances, an additional softening comonomer such as an acrylate can also be included to form a terpolymer. The pendent ionic groups in the ionomeric resins interact to form ion-rich aggregates contained in a non-polar polymer matrix. The metal ions, such as sodium, zinc, magnesium, lithium, potassium, calcium, etc. are used to neutralize some portion of the acid groups in the copolymer resulting in a thermoplastic elastomer exhibiting enhanced properties, i.e. improved durability, etc. for golf ball construction over balata.
The ionomeric resins utilized to produce cover compositions can be formulated according to known procedures such as those set forth in U.S. Pat. No. 3,421,766 or British Patent No. 963,380, with neutralization effected according to procedures disclosed in Canadian Patent Nos. 674,595 and 713,631, wherein the ionomer is produced by copolymerizing the olefin and carboxylic acid to produce a copolymer having the acid units randomly distributed along the polymer chain. Broadly, the ionic copolymer generally comprises one or more xcex1-olefins and from about 9 to about 20 weight percent of xcex1, xcex2-ethylenically unsaturated mono- or dicarboxylic acid, the basic copolymer neutralized with metal ions to the extent desired.
In this regard, generally at least 20% of the carboxylic acid groups of the copolymer are neutralized by the metal ions (such as sodium, potassium, zinc, calcium, magnesium, and the like) and exist in the ionic state. Suitable olefins for use in preparing the ionomeric resins include ethylene, propylene, butene-1, hexene-1, and the like. Unsaturated carboxylic acids include acrylic, methacrylic, ethacrylic, xcex1-chloroacrylic, crotonic, maleic, fumaric, itaconic acids, and the like. The ionomeric resins utilized in the golf ball industry are generally copolymers of ethylene with acrylic (i.e. Escor(copyright)) and/or methacrylic (i.e. Surlyn(copyright)) acid. In addition, two or more types of ionomeric resins may be blended into the cover compositions in order to produce the desired properties of the resulting golf balls.
Along this line, the properties of the cover compositions and/or the ionomeric resins vary according to the type and amount of the metal cation, the molecular weight, the composition of the base resin (i.e. the nature of the relative content of the olefin, the unsaturated carboxylic acid groups, etc.), the amount of acid, the degree of neutralization and whether additional ingredients such as reinforcement agents or additives are utilized. Consequently, the properties of the ionomer resins can be controlled and varied in order to produce golf balls having different playing characteristics, such as differences in hardness, playability (i.e. spin, feel, click, etc.), durability (i.e. impact and/or cut resistance), and resilience (i.e. coefficient of restitution).
However, while there are currently more than fifty commercial grades of ionomers available from DuPont and Exxon with a wide range of properties which vary according to the type and amount of metal cations, molecular weight, composition of the base resin (i.e. relative content of ethylene and methacrylic and/or acrylic acid groups), the degree of neutralization and additive ingredients such as reinforcement agents, etc., a great deal of research continues in order to develop golf ball cover compositions exhibiting not only the playability characteristics previously associated with the balata cover, but also the improved impact resistance and carrying distance properties produced by the ionomeric resins. Thus, an object of the present invention is to provide golf ball cover compositions which, when utilized in golf ball construction, produce balls exhibiting improved travel distance while maintaining satisfactory playability and durability properties.
In enhancing the distance a golf ball will travel when hit, there are a variety of factors which are considered. The coefficient of restitution, along with ball size, weight and additional factors such as club head speed, angle of trajectory, and ball aerodynamics (i.e., dimple pattern), generally determine the distance a ball will travel when hit. Since club head speed and the angle of trajectory are not factors easily controllable, particularly by golf ball manufacturers, the factors of concern among manufacturers are the coefficient of restitution and the surface dimple pattern of the ball.
A golf ball""s coefficient of restitution (C.O.R.) is the ratio of the relative velocity of the ball after direct impact to that before impact. One way to measure the coefficient of restitution is to propel a ball at a given speed against a hard massive surface, and measure its incoming velocity and outgoing velocity. The coefficient of restitution is defined as the ratio of the outgoing velocity to incoming velocity of a rebounding ball and is expressed as a decimal. As a result, the coefficient of restitution can vary from zero to one, with one being equivalent to an elastic collision and zero being equivalent to an inelastic collision.
The coefficient of restitution of a one-piece golf ball is a function of the ball""s composition. In a two-piece or a multi-layered golf ball, the coefficient of restitution is a function of the core, the cover and any additional layer. While there are no United States Golf Association (U.S.G.A.) limitations on the coefficient of restitution values of a golf ball, the U.S.G.A. requires that the golf ball cannot exceed an initial velocity of 255 feet/second. As a result, golf ball manufacturers generally seek to maximize the coefficient of restitution of a ball without violating the velocity limitation.
In various attempts to produce a high coefficient of restitution golf ball exhibiting the enhanced travel distance desired, the golfing industry has blended various ionomeric blends. However, many of these blends do not exhibit the durability and playability characteristics necessary for repetitive play and/or the enhanced travel distance desired.
The present invention is directed to the discovery that specific ionomer resins containing relative high amounts of acid (i.e. greater than 16 weight percent acid, preferably from about 17 to about 25 weight percent acid, and more preferably from about 18.5 to about 21.5 weight percent) and partially neutralized with sodium, zinc and magnesium ions, produce, when blended and melt processed according to the parameters set forth below, cover compositions exhibiting enhanced coefficient of restitution values when compared to low acid ionomers, or blends of low acid ionomer resins containing 16 weight percent acid or less. The new high acid ionomer cover compositions produce golf balls which exhibit properties of enhanced carrying distance (i.e. possess higher coefficient of restitution values) over known ionomer blends such as those set forth in U.S. Pat. Nos. 4,884,814 and 4,911,451, without sacrificing desirable characteristics such as playability and/or durability.
Along this line, until relatively recently, all of the ionomer resins commercially available contained at most 15 to 16 weight percent carboxylic acid. In 1989, Dupont introduced a number of new high acid ionomers and suggested that these new ionomers may have some use in previously known low acid ionomer applications such as the production of shoe soles, box toes, bowling pins, golf balls, ski boots, auto trim, etc.
Furthermore, Dupont suggested in a research disclosure (E. I. DuPont de Nemours and Co., Research Disclosure No. 297,003) that ionomers produced from polymers of ethylene acrylic acid or methacrylic acid containing greater than 15 weight percent acid can be melt processed to produce articles (i.e. golf balls, foot wear, ski boots, cosmetic bottle cap closures and so on) with good properties (i.e. improved stiffness, hardness and clarity) when compared with ionomers with lower acid levels.
However, not only has little information been provided concerning the acid levels and types of effective ionomers, particularly with respect to the art of golf ball manufacturing, it has been found that many cover compositions produced from polymers of ethylene/acrylic acid or ethylene/methacrylic acid containing greater than 15 weight percent acid have been dissatisfactory in that these compositions exhibit processing problems or are generally short on distance and/or durability and thus, are not particularly commercially viable. Similar poor results have been produced with covers composed of blends of high and low acid ethylene/acrylic acid or ethylene/methacrylic acid polymers and/or covers produced from single high acid ionomers.
The present invention is directed to improved golf ball covers made from specific blends of two or more high acid ionomers which do not exhibit the processing, distance and/or durability limitations demonstrated by the prior art. It has been found that these difficulties can be overcome utilizing the improved high acid ionomer blends of the present invention.
These and other objects and features of the invention will be apparent from the following description and from the claims.
In one aspect, the present invention is directed to a golf ball comprising a core and a cover, wherein the cover comprises a blend of two or more high acid ionomer resins. Each high acid ionomer resin utilized in the blend of the cover composition comprises generally greater than 16% by weight acid, preferably from about 17 to about 25% by weight acid and more preferably from about 18.5% to about 21.5% by weight acid. The acid groups of the high acid ionomers utilized in the cover compositions of the invention are partially (i.e. generally 10-75 percent, preferably 30-70 percent) neutralized by metal ions such as by sodium, zinc and magnesium ions. When the blend of two or more high acid ionomer resins is utilized to manufacture a golf ball, the golf ball produced thereby, exhibits properties of improved distance without sacrificing characteristics such as playability and/or durability when compared to low acid ionomer and/or low acid/high acid ionomer blends.
In another aspect, the invention relates to a golf ball comprising a core and a cover, wherein the cover comprises a blend of at least two high acid ionomer resins. Each high acid ionomer resin is comprised of an ethylene-methacrylic acid copolymer or an ethylene-acrylic acid copolymer containing greater than 16% by weight acid, preferably from about 17 to about 25% by weight acid, and more preferably from about 18.5 to about 21.5% by weight acid, with from about 10% to about 75% by weight (preferably from about 30% to about 70% by weight) of the carboxylic acid groups neutralized by metal ions such as by sodium, zinc or magnesium ions. Preferably, although not necessarily, the high acid ionomers utilized to produce the cover compositions of the invention have the same type of monocarboxylic acid (i.e. both are methacrylic acid or acrylic acid type high acid ionomers). In addition, the cover may consist of one or more additional ingredients such as pigments, dyes, U.V. absorbers and optical brighteners.
In a further aspect, the present invention concerns a golf ball comprising a core and a cover, wherein the cover is comprised of a blend of an ethylene-methacrylic acid copolymer containing greater than 16% by weight methacrylic acid, preferably from about 17% to about 25% by weight methacrylic acid, and more preferably 18.5% to about 21.5% by weight methacrylic acid, having from about 10% to about 75% of the carboxylic acid groups neutralized with sodium ions, and an ethylene-methacrylic acid copolymer containing greater than 16% by weight methacrylic acid, preferably from about 17% to about 25% by weight methacrylic acid, and more preferably 18.5% to about 21.5% by weight methacrylic acid, having from about 10% to about 75% of the carboxylic acid groups neutralized with zinc or magnesium ions. The ratio of sodium-high acid ethylene-methacrylic acid based ionomer to zinc or magnesium-high acid ethylene-methacrylic acid based ionomer is from about 90% to about 10% and from about 10% to about 90%. A more preferred range is from about 75% to about 25% and from about 25% to about 75%.
In a still another aspect, the invention relates to a golf ball comprising a core and a cover, wherein the cover comprises a blend of an ethylene-acrylic acid copolymer containing greater than 16% by weight acrylic acid, preferably from about 17 to about 25% by weight acrylic acid, and more preferably from about 18.5% to about 21.5% by weight acrylic acid, having from about 10% to about 75% of the carboxylic acid groups neutralized with sodium ions, and of an ethylene-acrylic acid copolymer containing greater than 16% by weight acrylic acid, preferably from about 17 to about 25% by weight acrylic acid, and more preferably from about 18.5% to about 21.5% by weight acrylic acid, having from about 10 to about 75% of the carboxylic acid groups neutralized with zinc or magnesium ions. The ratio of sodium-high acid ethylene-acrylic acid based ionomer to zinc or magnesium-high acid ethylene acrylic acid based ionomer is from 90% to about 10% and from 10% to about 90%. A more preferred range is from about 75% to about 25% and from about 25% to about 75%.
In a still further aspect, the invention is directed to a cover composition comprised of two or more high acid ionomer resins, wherein each high acid ionomer resin is comprised generally of greater than 16% by weight acid, preferably about 17 to about 25% by weight acid and more preferably from about 18.5% to about 21.5% by weight acid, and wherein each high acid ionomeric resin is from about 10 to about 75% by weight neutralized by metal ions such as by sodium, zinc and magnesium ions. The high acid ionomer resins produce, when blended and molded around solid or wound cores to formulate a cover composition, golf balls exhibiting enhanced distance (i.e. improved C.O.R.) without adversely affecting the balls"" playability and/or durability characteristics.
The present invention relates to improved cover compositions for golf ball construction. Specifically, according to the invention, golf balls having improved coefficient of restitution (C.O.R.) values are obtained using a cover material comprising specific blends of two or more high acid ionomers.
In this regard, the term xe2x80x9chigh acid ionomersxe2x80x9d refers broadly to recently developed ionomer resins containing greater than 16 weight percent acid, preferably from about 17 to about 25 weight percent acid and more preferably from about 18.5 to about 21.5 weight percent methacrylic acid or acrylic acid. When utilized in golf ball cover construction, it has been found that the high acid ionomers, particularly blends of sodium and zinc high acid ionomers, as well as blends of sodium and magnesium high acid ionomers, extend the range of hardness beyond that previously obtainable while maintaining the beneficial properties (i.e. durability, click, feel, etc.) of the softer low acid ionomer covered balls, such as balls produced utilizing the low acid ionomers disclosed in U.S. Pat. Nos. 4,884,814 and 4,911,451. By using the high acid ionomer resins of the present invention, harder, stiffer golf balls having higher C.O.R.s, and thus longer distance, are obtained.
The high acid ionomers suitable for use in the present invention are ionic copolymers which are the metal, i.e. sodium, zinc, magnesium, etc., salts of the reaction product of an olefin having from 2 to 8 carbon atoms and an unsaturated monocarboxylic acid having from about 3 to 8 carbon atoms. Preferably, the ionomeric resins are copolymers of ethylene and either acrylic or methacrylic acid. In some circumstances, an additional comonomer such as an acrylate ester (i.e. iso- or n-butylacrylate, etc.) can also be included to produce a softer terpolymer. The carboxylic acid groups of the copolymer are partially neutralized (i.e. approximately 10-75%, preferably 30-70%) by the metal ions. Of critical importance, each of the high acid ionomer resins included in the cover compositions of the invention must contain greater than 16% by weight of a carboxylic acid, preferably from about 17% to about 25% by weight of a carboxylic acid, more preferably from about 18.5% to about 21.5% by weight of a carboxylic acid.
Although the scope of the patent embraces all known high acid ionomeric resins falling within the parameters set forth above, only a relatively limited number of these high acid ionomeric resins are currently available. In this regard, the high acid ionomeric resins available from E. I. DuPont de Nemours Company under the trademark xe2x80x9cSurlyn(copyright)xe2x80x9d, and the high acid ionomer resins available from Exxon Corporation under either the trademark xe2x80x9cEscor(copyright)xe2x80x9d or the tradename xe2x80x9cIotekxe2x80x9d are examples of available high acid ionomeric resins which may be utilized in the present invention in the particular combinations described in detail below.
The high acid ionomeric resins available from Exxon under the designation xe2x80x9cEscor(copyright)xe2x80x9d and/or xe2x80x9cIotekxe2x80x9d, are somewhat similar to the high acid ionomeric resins available under the xe2x80x9cSurlyn(copyright)xe2x80x9d trademark. However, since the Escor(copyright)/Iotek ionomeric resins are sodium or zinc salts of poly(ethylene acrylic acid) and the xe2x80x9cSurlyn(copyright)xe2x80x9d resins are zinc, sodium, magnesium, etc. salts of poly(ethylene methacrylic acid) distinct differences in properties exist.
Examples of the high acid methacrylic acid based ionomers found suitable for use in accordance with this invention include Surlyn(copyright) AD-8422 (sodium cation), Surlyn(copyright) 8162 (zinc cation), Surlyn(copyright) SEP-503-1 (zinc cation), and Surlyn(copyright) SEP-503-2 (magnesium cation). According to Dupont, all of these ionomers contain from about 18.5 to about 21.5% by weight methacrylic acid.
More particularly, Surlyn(copyright) AD-8422, is currently commercially available from DuPont in a number of different grades (i.e. AD-8422-2, AD-8422-3, AD-8422-5, etc.) based upon differences in melt index. According to DuPont, Surlyn(copyright) AD-8422 offers the following general properties when compared to Surlyn(copyright) 8920 the stiffest, hardest of all of the low acid grades (referred to as xe2x80x9chardxe2x80x9d ionomers in U.S. Pat. No. 4,884,814):
In comparing Surlyn(copyright) 8920 to Surlyn(copyright) 8422-2 and Surlyn(copyright) 8422-3, it is noted that the high acid Surlyn(copyright) 8422-2 and 8422-3 ionomers have a higher tensile yield, lower elongation, slightly higher Shore D hardness and much higher flexural modulus. Surlyn(copyright) 8920 contains 15 weight percent methacrylic acid and is 59% neutralized with sodium.
In addition, Surlyn(copyright) SEP-503-1 (zinc cation) and Surlyn(copyright) SEP-503-2 (magnesium cation) are high acid zinc and magnesium versions of the Surlyn(copyright) AD 8422 high acid ionomers. When compared to the Surlyn(copyright) AD 8422 high acid ionomers, the Surlyn(copyright) SEP-503-1 and SEP-503-2 ionomers can be defined as follows:
Furthermore, Surlyn(copyright) 8162 is a zinc cation ionomer resin containing approximately 20% by weight (i.e. 18.5-21.5% weight) methacrylic acid copolymer that has been 30-70% neutralized. Surlyn 8162 is currently commercially available from DuPont.
For comparison purposes, examples of commercially available low acid methacrylic acid based ionomer resins are set forth below. These are many of the xe2x80x9chardxe2x80x9d ionomers utilized in the cover composition disclosed in U.S. Pat. No. 4,884,814. Along this line, the low acid ionomer resin cover compositions disclosed in the ""814 patent are generally considered to be among the best prior art methacrylic acid based cover compositions currently available from Spalding and Evenflo Companies, Inc., the assignee of the present invention.
Examples of the high acid acrylic acid based ionomers suitable for use in the present invention include the Escor(copyright) or Iotek high acid ethylene acrylic acid ionomers recently produced by Exxon. In this regard, Escor(copyright) or Iotek 959 is a sodium ion neutralized ethylene-acrylic acid copolymer and Escor(copyright) or Iotek 960 is a zinc neutralized ethylene-acrylic acid copolymer. According to Exxon, Ioteks 959 and 960 contain from about 19.0 to about 21.0% by weight acrylic acid with approximately 30 to about 70 percent of the acid groups neutralized with sodium and zinc ions respectfully. The physical properties of these high acid acrylic acid based ionomers are as follows:
For comparison purposes, examples of commercially available low acid acrylic acid based ionomer resins, such as these utilized in U.S. Pat. No. 4,911,451 are set forth below.
Furthermore, as indicated more particularly below in the Examples, cover compositions utilizing blends of two or more of the high acid ethylene acrylic acid based ionomers produced enhanced results and thus are the more preferred high acid ionomers over cover compositions produced utilizing blends of two or more high acid methacrylic acid based ionomers.
According to the present invention, it has been found that when two or more of the above-indicated high acid ionomers, particularly blends of sodium and zinc high acid ionomers, or blends of sodium and magnesium high acid ionomers, are processed according to the parameters set forth below to produce the covers of multi-layered golf balls, the resulting golf balls will travel further than previously known low acid ionomer resin covers and/or covers produced from high acid ionomers and/or high acid/low acid ionomer blends due to the balls"" enhanced coefficient of restitution values. This is particularly important in that an improvement of 0.001 in C.O.R. generally relates to our improvement of about 0.2 to 0.5 yards in travel distance. In addition, the resulting golf balls maintain the playability and durability characteristics exhibited by known low-acid ionomer resin covered balls.
When blends of sodium and zinc high acid ionomers are used, the ratio of sodium high acid ionomer to zinc high acid ionomer can be from about 90% to about 10% and from about 10% to about 90%. A more preferred range is from about 75% to about 25% and from about 25% to about 75%.
Similarly, when blends of sodium and magnesium high acid ionomers are utilized, the ratio of sodium high acid ionomer to magnesium high acid ionomer can be from about 90% to about 10% and from about 10% to about 90%. A more preferred range is from about 75% to about 25% and from about 25% to about 75%.
Additional compatible additive materials may also be added to the compositions of the present invention, such as dyes (for example, Ultramarine Blue sold by Whitaker, Clark, and Daniels of South Painsfield, N.J.), and pigments, i.e. white pigments such as titanium dioxide (for example Unitane 0-110) zinc oxide, and zinc sulfate, as well as fluorescent pigments. As indicated in U.S. Pat. 4,884,814, the amount of pigment and/or dye used in conjunction with the polymeric cover composition depends on the particular base ionomer mixture utilized and the particular pigment and/or dye utilized. The concentration of the pigment in the polymeric cover composition can be from about 1% to about 10% as based on the weight of the base ionomer mixture. A more preferred range is from about 1% to about 5% as based on the weight of the base ionomer mixture. The most preferred range is from about 1% to about 3% as based on the weight of the base ionomer mixture. The most preferred pigment for use in accordance with this invention is titanium dioxide.
Moreover, since these are various hues of white, i.e. blue white, yellow white, etc., trace amounts of blue pigment may be added to the cover stock composition to impart a blue white appearance thereto. However, if different hues of the color white are desired, different pigments can be added to the cover composition at the amounts necessary to produce the color desired.
In addition, it is within the purview of this invention to add to the cover compositions of this invention compatible materials which do not affect the basic novel characteristics of the composition of this invention. Among such materials are antioxidants (i.e. Santonox R), antistatic agents, stabilizers and processing aids. The cover compositions of the present invention may also contain softening agents, such as plasticizers, etc., and reinforcing materials such as glass fibers and inorganic fillers, as long as the desired properties produced by the golf ball covers of the invention are not impaired.
Furthermore, optical brighteners, such as those disclosed in U.S. Pat. No. 4,679,795, may also be included in the cover composition of the invention. Examples of suitable optical brighteners which can be used in accordance with this invention are Uvitex OB as sold by the Ciba-Geigy Chemical Company, Ardaley, N.Y. Uvitex OB is thought to be 2,5-Bis(5-tert-butyl-2-benzoxazoly)thiopene. Examples of other optical brighteners suitable for use in accordance with this invention are as follows: Leucopure EGM as sold by Sandoz, East Hanover, N.J. 07936. Leucopure EGM is thought to be 7-(2h-naphthol(1,2-d)-triazol-2yl)-3phenyl-coumarin. Phorwhite K-20G2 is sold by Mobay Chemical Corporation, P.O. Box 385, Union Metro Park, Union, N.J. 07083, and is thought to be a pyrazoline derivative, Eastobrite OB-1 as sold by Eastman Chemical Products, Inc. Kingsport, Tenn., is thought to be 4,4-Bis(benzoxaczoly)stilbene. The above-mentioned Uvitex and Eastobrite OB-1 are preferred optical brighteners for use in accordance with this invention.
Moreover, since many optical brighteners are colored, the percentage of optical brighteners utilized must not be excessive in order to prevent the optical brightener from functioning as a pigment or dye in its own right.
The percentage of optical brighteners which can be used in accordance with this invention is from about 0.01% to about 0.5% as based on the weight of the polymer used as a cover stock. A more preferred range is from about 0.05% to about 0.25% with the most preferred range from about 0.10% to about 0.020% depending on the optical properties of the particular optical brightener used and the polymeric environment in which it is a part.
Generally, the additives are admixed with a ionomer to be used in the cover composition to provide a masterbatch (M.B.) of desired concentration and an amount of the masterbatch sufficient to provide the desired amounts of additive is then admixed with the copolymer blends.
The cover compositions of the present invention may be produced according to conventional melt blending procedures. In this regard, two or more of the above indicated high acid ionomeric resins are blended along with the masterbatch containing the desired additives in a Banbury type mixer, two-roll mill, or extruded prior to molding. The blended composition is then formed into slabs or pellets, etc. and maintained in such a state until molding is desired. Alternatively a simple dry blend of the pelletized or granulated resins and color masterbatch may be prepared and fed directly into the injection molding machine where homogenization occurs in the mixing section of the barrel prior to injection into the mold. If necessary, further additives such as an inorganic filler, etc., may be added and uniformly mixed before initiation of the molding process.
Moreover, golf balls of the present invention can be produced by molding processes currently well known in the golf ball art. Specifically, the golf balls can be produced by injection molding or compression molding the novel cover compositions about wound or solid molded cores to produce a golf ball having a diameter of about 1.680 inches or greater and weighing about 1.620 ounces. The standards for both the diameter and weight of the balls are established by the United States Golf Association (U.S.G.A.). Although both solid core and wound cores can be utilized in the present invention, as a result of their lower cost and superior performance, solid molded cores are preferred over wound cores.
Conventional solid cores are typically compression molded from a slug of uncured or lightly cured elastomer composition comprising a high cis content polybutadiene and a metal salt of an xcex1, xcex2, ethylenically unsaturated carboxylic acid such as zinc mono or diacrylate or methacrylate. To achieve higher coefficients of restitution in the core, the manufacturer may include a small amount of a metal oxide such as zinc oxide. In addition, larger amounts of metal oxide than those that are needed to achieve the desired coefficient may be included in order to increase the core weight so that the finished ball more closely approaches the U.S.G.A. upper weight limit of 1.620 ounces. Other materials may be used in the core composition including compatible rubbers or ionomers, and low molecular weight fatty acids such as stearic acid. Free radical initiator catalysts such as peroxides are admixed with the core composition so that on the application of heat and pressure, a complex curing or cross-linking reaction takes place.
The term xe2x80x9csolid coresxe2x80x9d as used herein refers not only to one piece cores but also to those cores having a separate solid layer beneath the cover and above the core as in U.S. Pat. No. 4,431,193, and other multilayer and/or non-wound cores (such as those described in U.S. Pat. No. 4,848,770).
Wound cores are generally produced by winding a very large elastic thread around a solid or liquid filled balloon center. The elastic thread is wound around the center to produce a finished core of about 1.4 to 1.6 inches in diameter, generally. Since the core material is not an integral part of the present invention, a detailed discussion concerning the specific types of core materials which may be utilized with the cover compositions of the invention are not specifically set forth herein. In this regard, the cover compositions of the invention may be used in conjunction with any standard golf ball core.
As indicated, the golf balls of the present invention may be produced by forming covers consisting of the compositions of the invention around cores by conventional molding processes. For example, in compression molding, the cover composition is formed via injection at about 380xc2x0 F. to about 450xc2x0 F. into smooth surfaced hemispherical shells which are then positioned around the core in a dimpled golf ball mold and subjected to compression molding at 200-300xc2x0 F. for 2-10 minutes, followed by cooling at 50-70xc2x0 F. for 2-10 minutes, to fuse the shells together to form an unitary ball. In addition, the golf balls may be produced by injection molding, wherein the cover composition is injected directly around the core placed in the center of a golf ball mold for a period of time at a mold temperature of from 50xc2x0 F. to about 100xc2x0 F. After molding the golf balls produced may undergo various further finishing steps such as buffing, painting, and marking as disclosed in U.S. Pat. No. 4,911,451.

Golf ball covers containing high acid ionomers


A fibrous anhydrous magnesium oxysulfate having a rational formula of MgSO.sub.4.5Mg(OH).sub.2 has an excellent oil absorptivity and appropriate hygroscopicity. The fibrous anhydrous magnesium oxysulfate is prepared by a process comprising cooling and diluting, with water or an aqueous solution of magnesium sulfate, a slurry of magnesium oxysulfate having a rational formula of 2MgSO.sub.4.Mg(OH).sub.2.3H.sub.2 O, obtained by dispersing magnesium hydroxide or magnesium oxide into an aqueous solution of magnesium sulfate, and then subjecting the dispersion to hydrothermal reaction, to thereby decompose the 2MgSO.sub.4.Mg(OH).sub.2.3H.sub.2 O and produce fibrous magnesium oxysulfate having a rational formula of MgSO.sub.4.5Mg(OH).sub.2.8H.sub.2), and then heat-treating the fibrous magnesium oxysulfate having the rational formula of MgSO.sub.4.5Mg(OH).sub.2.8H.sub.2 O.

1. Field of the Invention
The present invention relates to anhydrous fibrous magnesium oxysulfate and a process for the preparation thereof. This anhydrous fibrous magnesium oxysulfate may be suitably utilized as an additive for a resin, filler or filter medium, due to the fibrous structure thereof.
2. Description of the Related Art
Magnesium oxysulfates with different structures are known, and fibrous MgSO.sub.4.5Mg(OH).sub.2.3H.sub.2 O is already in use as a reinforcing material for resins, and the like. Further, MgSO.sub.4.5Mg(OH).sub.2.8H.sub.2 O also has a fibrous structure, and as a process for the preparation thereof, there is known a process for synthesizing same directly from magnesium oxide and magnesium sulfate. This process, however, is unsatisfactory in various aspects, such as conversion and production cost, when producing this compound on an industrial scale. These fibrous magnesium sulfates contain water of crystallization in the structures thereof, as apparent from the rational formulae thereof, but are dehydrated at a temperature of from 100.degree. to 300.degree. C., resulting in defective moldings when used for resins to be processed at a temperature exceeding this temperature range.

Fibrous anhydrous magnesium oxysulfate and process for the preparation thereof


A method of controlling an auxiliary pump for supplying the hydraulic fluid of a hybrid transmission of a vehicle. The auxiliary pump, after the expiration of a predetermined time interval of deactivation, is activated to prevent accumulation of air in the intake area of the auxiliary pump. In addition, a device for the execution of the method, in which a control device is provided which has its signals connected with the electric auxiliary pump for the purpose of controlling the auxiliary pump in order to prevent accumulation of air in the intake area of the auxiliary pump.

It is known in the vehicle technology that hybrid transmissions utilize an electric auxiliary pump to guarantee the hydraulic supply or rather oil supply. The auxiliary pump is actuated if the oil supply cannot be covered by means of a main pump on the transmission side because the transmission input rotational speed is too low. It is hereby assumed that the electric auxiliary pump can immediately start the oil supply when switched on. However, it requires that the intake port and the intake duct are filled with oil so that no air and no oil foam are present. Otherwise, unwanted air intake takes place when the auxiliary pump is again switched on, so that the oil supply of the transmission during that time interval is below the necessary level and therefore shift elements, for instance, cannot be activated.
For instance, known from the publication DE 10 2008 040 667 A1 is a hydraulic system with a transmission device having a main transmission pump and an auxiliary pump, as well as a method to operate the hydraulic system. In the known hydraulic system, to avoid unwanted outflow of the hydraulic fluid or rather oil, in the area of the auxiliary pump into an unpressurized area or into an oil sump, an additional switch-over valve is required which separates the auxiliary pump from the secondary pressure circuit. This not only requires a larger construction effort but it is also costly.

Method and device for controlling an auxiliary pump for a transmission


A pre-stressed annular sealant and method of creating a durable seal in a well bore annulus which is based on hydraulic cement that is designed to be easily pumped and placed into a casing-wellbore annulus, to set into a hardened mass, and to then undergo post-set crystal growth and phase changes in the crystalline matrix to combat inherent volumetric shrinkage and to create internally-generated compressive stress in the cement matrix. This internally-generated compressive pre-stressing compensates for tensile stress induced by well operations. The tensile stress must be greater in magnitude than the magnitude of the compressive pre-stress plus the magnitude of the cement's tensile strength before the cement sheath will fail in tension. This expansion and pre-stressing also creates significantly higher shear bond strengths than those developed with ordinary hydraulic cement.

1. Field of the Invention
The method of the present invention relates to oil and gas production. More particularly, the present invention relates to a method of providing a durable sealant to prevent communication through the annular space formed between a drilled well bore and an inserted casing string in order to isolate the producing formation from all other formations exposed by drilling the hole.
Furthermore, the problem addressed by this invention is long-term sealing for zone isolation in petroleum wells. The need for a durable sealant to prevent communication through the annular space formed between a drilled well bore and an inserted casing string is driven by the need to isolate the producing formation that is targeted during the well drilling process from all other formations exposed by drilling the hole. In addition, the purpose is to isolate all formations that are drilled through from all other formations. An example is isolating potable water zones from brackish or salt water zones, and obviously from the producing formation. This isolation guarantees that hydrocarbons produced from the formation must flow into the casing and not around it. Additionally, zone isolation ensures that treatment fluids pumped into the formation to stimulate it will not flow into the annulus. This seal must withstand thermal and hydraulic stresses imposed on it throughout the well's life. The magnitudes of these stresses caused by well intervention, hydraulic fracturing, continued drilling below the casing, etc. can be significantly higher than one would imagine: on the order of several thousand psi. Additionally stresses can be either compressive or tensile.
2. General Background of the Present Invention
Hydraulic cement is routinely used as a sealant for oil and gas wells. While the composition seems to be ideal for the application since it is fluid for placement and then sets to a hard solid, set hydraulic cement has very low tensile strength. Most of the stresses generated on the annular sealant are tensile and of magnitude sufficient to create cement sheath failure.
The term "hydraulic cement" is meant to encompass any inorganic cement that hardens or sets underwater. Hydraulic cements, for example, include Portland cement, aluminous and pozzolan cement, and the like. The term "hydraulic cement" is also intended to include cements having minor amounts of extenders such as bentonite, gilsonite, and also is intended to include cements used either without any appreciable sand or aggregate material or such cements and admixed with a granular filling material such as sand, ground limestone, and the like. Thus, for example, any of the Class "A-H" and "J" cements as listed in the "ANSI/API Recommended Practice 10B-2 First Edition, July 2005" are suitable for this purpose.
This failure of cement seal in an annulus of a well previously sealed is documented routinely in the industry. Stress is induced by thermal cycling, pressure cycling, ceasing or re-initiating production, etc. Tensile hoop stresses imposed during these operations are easily sufficient in magnitude to cause seal failure.
Extensive prior art exists. Expansive reaction of MgO in cement is documented. Four patents are cited here as reference.
PAT. NO.TITLE4,797,159Expandable Cement Composition5,718,292Inflation Packer Method and Apparatus5,942,031Expanding Additive For Cement Composition7,036,586Methods of Cementing in Subterranean FormationsUsing Crack resistant Cement Compositions
Expansion is noted, but pre-stressing effects are not realized since concentration is insufficient. It is believed that the concentration range claimed is the reason pre-stressing occurs and results in improved seal performance.
Many other references to MgO as a cement additive are specific for formulation of MgOCl cement. This material is acid-soluble but offers no benefit in the way of pre-stressing the cement matrix.
The following illustrations represent the stresses imposed on an element of cement in the cement sheath, and the effective stress state with Pre-Stressed Cement.

Pre-stressed annular sealant and method of creating a durable seal in a well bore annulus


Disclosed are methods and systems for creating, evaluating, and tuning a predictive engine for machine learning, and for replaying performance of the predictive engine, including steps to deploy a variant of the predictive engine; receive a plurality of queries to the predictive engine variant from an end-user device; apply a query segment filter to the plurality of queries to generate a replay group of queries, wherein for each query in the replay group, the engine variant generates a corresponding predicted result, receives a corresponding actual result, and computes a corresponding prediction score; group queries in the replay group into one or more segments; and generate, as a replay of the performance of the engine variant, an accumulated prediction score over each of the one or more query segments of the replay group by applying an accumulation function. The present invention substantially improves on systems that utilize predictive engines.

The statements in this section may serve as a background to help understand the invention and its application and uses, but may not constitute prior art.
Machine learning systems analyze data and establish models to make predictions and decisions. Examples of machine learning tasks include classification, regression and clustering. A predictive engine is a machine learning system that typically includes a data processing framework and one or more algorithms trained and configured based on collections of data. Such predictive engines are deployed to serve prediction results upon request. A simple example is a recommendation engine for suggesting a certain number of products to a customer based on pricing, product availabilities, product similarities, current sales strategy, and other factors. Such recommendations can also be personalized by taking into account user purchase history, browsing history, geographical location, or other user preferences or settings. Some existing tools used for building machine learning systems include APACHE SPARK MLLIB, MAHOUT, SCIKIT-LEARN, and R.
Recently, the advent of big data analytics has sparked more interest in the design of machine learning systems and smart applications. However, even with the wide availability of processing frameworks, algorithm libraries, and data storage systems, various issues exist in bringing machine learning applications from prototyping into production. In addition to data integration and system scalability, real-time deployment of predictive engines in a possibly distributed environment requires dynamic query responses, live model update with new data, inclusion of business logics, and most importantly, intelligent and possibly live evaluation and tuning of predictive engines to update the underlying predictive models or algorithms to generate new engine variants. In addition, existing tools for building machine learning systems often provide encapsulated solutions. Such encapsulations, while facilitating fast integration into deployment platforms and systems, make it difficult to identify causes for inaccurate prediction results. It is also difficult to extensively track sequences of events that trigger particular prediction results.
Therefore, in view of the aforementioned difficulties, there is an unsolved need to make it easy and efficient for developers and data scientists to create, deploy, evaluate, and tune machine learning systems.
It is against this background that various embodiments of the present invention were developed.

Methods and systems for visual replay of predictive engine performance


A method and system for generating a semantic point cloud map. Voice input is received via a microphone and converted into text via speech-to-text synthesis. The text is decomposed into semantic data comprising a number of words, and it is determined whether keywords of the semantic data are present in an autonomous driving (AD) ontology. In response to the keywords of the semantic data being present in the AD ontology, coordinates of a point cloud map corresponding to the semantic data are determined. An association between a semantic label determined from the words of the semantic data and coordinates in the point cloud map corresponding to the semantic data is generated and stored in a memory of the computer vision system.

Vehicle driver assistance systems that enhance the awareness and safety of human drivers and autonomous vehicles increase driver safety and convenience. Autonomous parking and driving are important aspects of autonomous vehicles. However, as with other aspects of autonomous vehicles, autonomous operations such as autonomous parking and driving remain a developing field and improvements in autonomous parking and driving are desirable.
Computer vision systems are an important component of a vehicle driver assistance systems and autonomous vehicles. Computer vision systems typically generate a point cloud map as part of spatial cognition. A point cloud is a large set of data points in a coordinate system, typically a three-dimensional (3D) coordinate system. Each data point in the point cloud has three (3) coordinates namely x, y, and z, which determine where the point is located along x, y, and z axes of the 3D coordinate system, respectively. One of the most accurate and common sources of point clouds, in particular in the autonomous driving domain, are laser-based imagery sensors, such as Light Detection and Ranging (LiDAR) sensor. A LiDAR usually operates in a fixed frequency, and generates a very large set of data points (e.g., 100,000 data points per 100 ms in Velodyne™ HDL-64E) in its local coordinate system, which is the center of LiDAR sensor.
LiDAR point clouds may be used in point cloud map generation. Point cloud map generation involves moving a scanning LiDAR around an environment (i.e., driving a LiDAR-equipped car in a neighborhood), collecting all the point clouds generated by the LiDAR, and combining the generated point clouds together to generate point cloud map. The generated point cloud map includes a larger set of 3D data points than a conventional point cloud and has extended boundaries. Point cloud maps may be utilized for map-based vehicle localization in vehicle driver assistance systems or autonomous vehicles during autonomous driving.
Conventional methods of generating point cloud maps do not provide any context. Improvements in computer vision systems and alternatives to existing solutions which provide context to the point cloud maps are desirable.

Method and system for generating a semantic point cloud map