A fiber optic connector for coupling focused radiant energy from a laser to a fiber optic conductor includes a secondary transmission path, one or more diffusers and, optionally, one or more internal heat sinks for diffusing radiant energy so as to and thereby minimize damage to the connector. In addition, coupling of the radiant energy to the cladding of the fiber is minimized by stripping or at least partially removing the cladding to reduce the amount of cladding in the area that extends to the focal plane of the radiant energy source, while reduction of higher order propagation modes may optionally be achieved by tapering a section of the fiber in such a manner that light entering the fiber at large critical angles are effectively collimated, i.e., bent towards the axis of the fiber.

1. Field of the Invention
This invention relates to improvements over the system disclosed in U.S. Pat. No. 5,179,610, in which radiation that fails to couple,with a small core fiber is transmitted via a secondary transmission path to a "dissipation chamber," a reflector, and an external heat sink that converts the reflected radiation to heat.
The first improvement is to use diffusion to spread-out the errant radiation, thereby minimizing damage caused by the radiation and eliminating the need for a reflector or external heat sink. As a result, the size and cost of the termination is reduced, and the termination can be fitted into existing fiber optic termination apparatus without the need for substantial modification. While an internal heat sink may be included, the heat sink can be made relatively small since it is only required to absorb diffuse radiation.
The second improvement is to strip away or reduce the thickness of the cladding at the coupling end of the fiber to reduce or eliminate launching energy into the cladding of the fiber.
The third improvement is to taper a section of the fiber core and/or cladding to decrease higher order radiant energy propagation modes within the conducting medium.
2. Description of Related Art
a. Apparatus to which the Invention may be Applied
The method and apparatus of the invention is especially suitable for use in connection with (but not limited to) relatively small primary optical transmission systems that employ optical fibers, and in particular medical devices such as scalpels or lithotripter fibers, which are typically, but not necessarily, monochromatic. Such optical fibers are especially useful to implement recently developed, minimally invasive surgical techniques.
An example of an apparatus to which the principles of the invention may be applied is illustrated in FIGS. 1 and 2. The apparatus includes a laser system 12 and a standard connector coupler 18 for coupling a connector such as connector 30 shown in FIG. 2, which couples the output of the laser system to a primary optical system such as an optical fiber or fiber cable 32. The laser may be a high energy pulse or continuous wave laser that generates a monochromatic radiant energy output beam 17. For example, the laser system may be a Holmium:YAG laser that generates an output formed of pulses on the order of 250μ seconds in pulse width and energy levels ranging up to 1800 mj/pulse with an average power of 12 Watts. The output beam 17 is passed through a condensing lens to form an output beam 17a that is focused on a spot 17b in the vicinity of input focal plane 16 and centered in a connector coupler 18 mounted on the laser enclosure 15 using respective X, Y, and Z adjustments 12a–12c. When connector 30 shown in FIG. 2 is secured to connector coupler 18 by locking member 40 (which may, for example, be an internally threaded nut), the connector ferrule 31 is ideally centered on focused spot 17b and the distal end of the connector ferrule is at the focal plane 16. In this example, the focused spot size at the focal plane 16 is on the order of 365 microns and the relative power density at the focal plane for a 365 micron spot with an average power of 12 watts is approximately 11.5 kW/cm2. On the other hand, the power density 6 mm beyond the focal plane 16 is reduced by a factor of 50.
Ferrule 31 of connector 30 is typically a metal elongated hollow body member into which is inserted the optical fiber or fiber cable 32. The proximal end has a fiber clearance hole 38 drilled close to the outside diameter of the fiber 35. To secure the fiber 35 to the ferrule 31, a small portion of the fiber optic cable 32 is stripper away exposing the glass fiber 35. Before the stripped fiber is placed inside ferrule 31, an adhesive 34 may be applied to a small portion of exposed fiber 35 and the exposed fiber is passed through the internal diameter of the ferrule to its distal end. The extreme distal portion of the exposed fiber exits the ferrule through fiber clearance hole 38. Later, after adhesive 34 is cured, the exposed fiber 35 is trimmed and polished such that the distal end of the ferrule and the distal end of the fiber 35 are flush. Alternately, the fiber 35 may be secured within the ferrule by crimping a portion of the cable 32 to the ferrule using a sleeve.
b. The Errant Radiation Problem
The errant radiant energy problem arises when the primary optical transmission system approaches or is smaller than the size of the focused beam of radiant energy. For example, the smaller the diameter of an optical fiber, the more difficult it is to focus energy from the laser into the core. If the core diameter is smaller than that of the focused spot of the laser source, or if the focused radiant energy to the core is misaligned or greater than the fiber's acceptance angle, then energy will be transferred to structures that make up the coupler or that surround the core. The density is often great enough to soften, melt, or fuse any materials which are not highly optically transmissive or reflective. In many cases the energy density can be so great that photo thermal ablation may occur in the metal housing of the connector that couples the laser to the fiber, causing the metal to explosively form a plume mixture gases and micron size particles, which re-deposit and contaminate the focusing lens. Further lasing into the contamination can create extreme localized heating which ultimately destroys the focusing lens.
One solution to the problem of errant radiant energy is to divert the radiant energy along a second transmission path to a heat sink situated in, or comprising, the connector support structure, as disclosed in U.S. Pat. No. 5,179,610. As a result, it is necessary to modify the support structure to serve as a heat sink, and to provide a reflector capable of withstanding the radiation transmitted thereto by the secondary transmission path. The secondary transmission path is required to be highly transmissive (see col. 4, lines 31–39 of U.S. Pat. No. 5,179,610) and may be in the form of a quartz, glass, or Zirconium Fluoride collar having some heat dissipating effects, but primarily provided to guide the errant radiation to the reflector, while the reflector may be in the form of a multifaceted polished metal structure interference fitted into the connector, and the heat sink may be in the form of a metal element bolted to the fiber optic connector at an appropriate position.
The arrangement disclosed in U.S. Pat. No. 5,179,610 can, in theory, effectively divert radiation away from components of the fiber optic termination or connector, but implementation of the arrangement requires replacement of the conventional supporting structure, making it difficult to adapt the arrangement to existing fiber terminations. Further, the arrangement requires a reflector capable of withstanding the radiation to be dissipated, and a supporting structure that can effectively convert the radiation to heat and dissipate it without exposing the user or other surrounding structures to the resulting heat. As a result, the arrangement disclosed in U.S. Pat. No. 5,179,610 does not appear to be compatible with existing laser systems and connectors, and in particular does not appear to be well-adapted for use with standard medical laser industry connectors, such as the SMA 905 standard connector.
There is therefore a need for a coupling apparatus and method that minimizes the impact of radiant energy that fails to couple to the core of the optical fiber (or other primary optical transmission system), and further that can be fitted into existing termination arrangements, without the need to add a heat sink or modify the termination to safely dissipate the radiation. While heat sink structures may be utilized in the termination arrangement of the invention, they are designed to fit within the termination, and do not require a reflector.
c. The Problem of Coupling to the Cladding
In addition to dissipating radiant energy that fails to couple with the fiber, the present invention addresses the problem that, even when all of the energy that fails to couple to the fiber is dissipated, some of the energy that couples to the fiber will couple to the cladding of the fiber rather than to the core, causing the cladding to act as a secondary wave guide and leak energy into surrounding coating during tight bends, such as my occur when the optical fiber is used for laser lithotripsy after it has been passed through the working channel of an endoscope. While the amount of coupling may be reduced by tapering, the core and cladding may mix, causing light to also mix into the cladding, and higher order modes may be created which are more subject to loss during a bend than lower order modes. By way of background, it was proposed in U.S. Pat. No. 6,282,349 to fuse the cladding to the ferrule in which it is placed, but the cladding fusion scheme described in this patent did not involve removal of some or all of the cladding at the end of the fiber reduce coupling of laser energy into the cladding.
An improvement over the arrangement of U.S. Pat. No. 5,179,610 is disclosed in copending U.S. patent application Ser. No. 10/370,453, filed Feb. 24, 2003, by the same inventor as the present application. This copending patent application describe a laser-to-fiber coupling arrangement that can be used without an external heat sink, by reflecting the errant laser energy back into the laser itself. This has the advantage of not only eliminating the heat sink, but also of enabling use of a less expensive and more reliable single facet reflector. In addition, the patent application discloses the concept of roughening the end surface of a transparent ferrule to diffuse incoming radiation so as to reduce the density of radiation incident on the reflector. However, while this represents an improvement over the arrangement disclosed in U.S. Pat. No. 5,179,610, elimination of the reflector entirely would have the additional advantages of shortening the secondary transmission path, simplifying manufacture, and increasing the useful life of the apparatus. There is still a need for a laser-to-fiber coupling arrangement that reduces or eliminates coupling of focused radiant energy into the cladding of an optical fiber, rather than into the core, and yet does not require an external heatsink or any sort of reflector.
b. The Problem of Higher Order Modes
When light propagating down a fiber core exceeds the critical angle created by the core/cladding interface due to tight bends in the fiber, light will leak from the core into the adjacent cladding and outer coating surfaces. Damage to the cladding or coating will occur if these surfaces are unable to withstand the incident power or energy density. Continued damage to these surfaces can ultimately lead to total destruction or breakage of the overall fiber. Since higher order radiation modes are by definition modes in which the angle of incidence is relatively high, higher order modes are more likely to exceed the critical angle at a bend in the fiber, and therefore leak to the cladding.
There are two conventional ways to deal with this problem. The first is to use the largest fiber numerical aperture (N.A.), thereby increase the acceptable angles at which energy from the source propagates within the light conducting medium. The second is to reduce the input numerical aperture from the source, which also has the effect of increasing the acceptable propagation angles. However, both solutions are undesirable for many applications. Larger N.A.s are limited, due to choices of fiber core/clad materials versus transmission at a particular wavelength. The N.A. of fiber is determined by the refractive indices of the core/clad materials.N.A.2=(ncore2−nclad2)Therefore, choices of larger N.A. fibers are limited in many state of the art minimally-invasive surgical techniques involving, for example, scalpels or lithotripter fibers, while decreasing the numerical aperture of the radiation source is often impractical due to the already large installed base of lasers, theoretical limitations and FDA regulations on making modifications to existing lasers. The present invention is especially useful in such cases, i.e., where it is necessary for the fiber to effectively reduce the source N.A., although the invention can be used in any context where propagation of higher order radiant energy modes is of concern.

Apparatus and method for diffusing laser energy that fails to couple into small core fibers, and for reducing coupling to the cladding of the fiber


A lightweight contact holographic sight includes a housing and a base which form a compartment containing a laser diode, an associated power source, and optical elements including a mirror, an off axis collimator, a reflection grating, and an image hologram of a reticle pattern, wherein the optical elements are arranged within the compartment to direct and fold the laser beam in a substantially generally vertical path. In one aspect of the invention, an elevation and windage adjustment mechanism is provided to rotate the reflection grating about two orthogonal axes to thereby adjust the projected reticle pattern for windage and elevation. In another aspect of the invention a removable battery compartment including a cam surface which is releasably contacted by a cam lever arm pivotally mounted on the sight housing or the base to allow for quick tool-less removal of the compartment for battery replacement.

This invention relates to a design for a lightweight holographic sighting device for use on firearms and bows.
There are several types of sights utilized with small arms, such as rifles, shotguns, hand guns, bows, and other similar, hand-held weapons, including sights which incorporate holographic images of various one, two and dimensional reticle patterns.
The Compact Holographic Sight disclosed in U.S. Pat. No. 5,483,362 issued to Tai et al describes the design of a holographic sight that is relatively compact. It is currently sold in the commercial market as the Bushnell(copyright) HOLOsight(copyright). Other HOLOsight(copyright) features are disclosed in U.S. Pat. No. 5,815,936 issued to Sieczka et al. The HOLOsight(copyright) is ideal for larger weapons such as rifles or shotguns and works well with larger caliber handguns. This sight, however, is too long and too heavy for some smaller handguns and some bows.
A number of compact hologram displays have been developed, including the edge illuminated holograms disclosed in U.S. Pat. Nos. 4,643,515 and 5,151,800, both also issued to Upatnieks. These hologram displays have a compact, monolithic structure. They also utilize a diffraction or reflection grating to minimize the effects of the wavelength drift of the laser diode light beam. These edge illuminated, monolithic displays however, have not been incorporated into sights because they are relatively expensive to manufacture.
It is thus desirable to reduce the weight and length of the holographic sight to make it practical as a sighting device for weapons of all types and sizes. It is also desirable to produce a design that can be manufactured at a lower cost.
It is therefore an object of the present invention to provide a holographic sight that is short enough in length and light enough in weight to be conveniently used on relatively small handguns and bows.
It is yet another object of the present invention that the sight can be manufactured at a lower cost.
It is yet another object of the present invention to provide a holographic sight including a windage end elevation adjustment mechanism which is stable and precise, yet simple, lightweight, and economical in design.
It is yet another object of the present invention to provide a collimator for a holographic sight which is simple in design, and economical to manufacture.
It is yet another object of the present invention to provide a battery powered sight which allows for quick and easy replacement of the batteries in the field.
In carrying out the above and other objectives, the lightweight holographic sight of the present invention includes a housing and a base which form a compartment containing a laser diode, an associated power source, and optical elements including a mirror, an off-axis collimator, a holographic reflection grating, and an image hologram of the reticle pattern, wherein the optical elements are arranged within the compartment to direct and fold the laser beam in a substantially generally vertical path.
The invention also preferably includes an elevation and windage adjustment mechanism which rotates the reflection grating about generally horizontal and vertical axes to thereby adjust the projected reticle pattern, and a removable battery compartment including a cam surface which is releasably contacted by a cam lever arm pivotally mounted on the housing or the base to allow for tool-less removal of the compartment for battery replacement.
The sight of the present invention is relatively more compact in its length, due to the above described arrangement of the optical elements. The vertically folded light path significantly shortens the sight, which in turn reduces the length of the metallic base and decreases the weight of the unit.
The diverging beam from the laser is collimated by an off-axis reflective collimator which is lighter than an equivalent collimating lens, and diffracted by a reflection grating. The diffracted light illuminates the reticle image hologram to form the holographic aiming reticle.
The base of the present invention also preferably includes a mounting mechanism that quickly and securely mounts the sight onto any standard Weaver(copyright) style scope rail.
As taught in U.S. Pat. No. 5,483,362, the emission wavelength of a laser diode changes with temperature, and the angle of diffraction is a function of wavelength. By simply illuminating a reticle image hologram with a laser diode, the angular position of the reconstructed image will not be stable. The reticle position will shift with a change in the case temperature of the laser diode. To produce a stable reticle image over a wide temperature range, the illuminating beam is diffracted first by a grating. The wavelength dependency can be removed by matching the dispersions of the grating and the reticle hologram. In the sight described in U.S. Pat. No. 5,483,362, a transmission grating bonded onto a prism is used to produce a dispersion equal to, but with the opposite sign of, the dispersion of the image hologram. In a preferred embodiment of the present invention, a reflection grating is used to compensate for the wavelength dependency of the diffraction by the image hologram. The reflection grating is lighter and more compact than the prism/transmission grating combination described in U.S. Pat. No. 5,483,362.
U.S. Pat. Nos. 5,483,362 and 5,815,936 teach that the angular position of the reconstructed reticle image may be changed for elevation and windage adjustments by rotating the image hologram while keeping the illuminating beam stationary. The adjustment mechanism disclosed in these patents is located behind the hologram, which adds to the overall length of the sight. It is made of aluminum to provide the strength needed to hold the image hologram and its metallic frame in place during recoil.
In the preferred embodiment of the present invention, the angular position of the reticle imaged is changed by rotating the reflection grating. The grating is smaller and lighter than the image hologram and is located inside the housing of the sight. Since the grating is not exposed, it does not have to be protected by its own special frame. This allows the elevation and windage mechanism to be made of a molded composite material, such as plastic, instead of metal, which reduces the production cost. The entire adjustment mechanism is located inside the housing, thereby protecting the mechanism from dirt. Moreover, a sight including this reflection grating adjustment mechanism can be shorter in length, which reduces the overall weight of the sight.
In the preferred embodiment, the batteries are placed inside a battery compartment which is then locked securely in place withing the housing via a cam lever.
A parabolic reflector is the ideal collimator but the aspheric surface is costly to produce. To minimize production costs, one embodiment of the present invention includes an off-axis collimator having two spherical surfaces of different radii. The collimator is preferably made of glass. The light passes through the glass, is reflected off the mirrored back surface of the optical element and through the glass again. The curvatures are chosen such that the spherical aberration is minimized.
As taught in U.S. Pat. No. 5,483,362, the brightness of the reticle image may be controlled by the average output power of a pulse width modulated laser diode. Lowering the duty cycle dims the reticle image. The dynamic range of the brightness control is limited by the narrowest pulse width that can be implemented. The disclosure of U.S. Pat. No. 5,483,362 relating to controlling the brightness of the reticle image with pulse width modulation is incorporated by reference herein.
Most mounts that attach an optical scope onto a Weaver(copyright) style rail on a gun use two bolts to tighten the clamps on either two physically separated mounting bases or an integrated mounting base. Because the present invention is significantly smaller than existing holographic sights in both the length and the weight, the mounting mechanism in the preferred embodiment has a single mounting bolt. The use of a single bolt speeds up the mounting and dismounting of the holographic sight. Moreover, the single bolt mount provides better repeatability than the traditional two-bolt mount which is sensitive to the relative tightening torques applied to the two bolts.
The above objects and other objects, features and advantages of the present invention are readily apparent from the following detailed description of the best mode for carrying out the invention when taken in connection with the accompanying drawings.


A bipolar transistor includes multiple coupled delta layers in the base region between the emitter and collector regions to enhance carrier mobility and conductance. The delta layers can be varied in number, thickness, and dopant concentration to optimize desired device performance and enhanced mobility and conductivity vertically for emitter to collector and laterally parallel to the delta-doped layers. The transistors can be homojunction devices or heterojunction devices formed in either silicon or III-V semiconductor material.

This invention relates generally to semiconductor devices, and more particularly the invention relates to bipolar transistor devices.
The bipolar transistor is comprised of an emitter region and a collector region of the same conductivity type in a semiconductor body separated by a base region of opposite conductivity type. Conduction in the bipolar transistor is controlled by the biases across both emitter-base and the collector-base junctions.
One of the key features of the bipolar transistor is its extremely high operating speed. At present the fastest bipolar devices are fabricated in III-V semiconducting materials, (e.g., aluminum gallium arsenide/gallium arsenide) semiconductor material. However, in order to attain a high level of integration in current technology, silicon-based semiconductor material must be used. Emitter engineering has been employed in heterojunction bipolar devices in order to improve speed and current gain by using wider band-gap materials for the emitter so that higher base doping can be achieved which leads to a lower base resistance. The reduction in base resistance results in higher operating frequencies. High operating frequencies have been demonstrated in silicon/germanium heterojunction bipolar transistors due to the use of highly doped base layers with reduced base resistance. Emitter engineering with heterojunctions has improved device performance but requires more complex device growth and processing.
Delta doped layers have been used in transistor devices to improve speed. A delta doped layer is a thin (e.g., 50 .ANG.) highly doped layer with a dopant concentration of 10.sup.13 or 10.sup.14 atoms per square centimeter, for example. The delta layer may be formed using molecular beam epitaxy or other advanced epitaxial techniques. Kuo et al. "Planarized Be Delta Doped Heterostructure Bipolar Transistor Fabricated Using Doping Selective Contact and Selective Hole Epitaxy," Japanese Journal of Applied Physics, Vol. 30, No. 2B, February, 1991, pp. 262-265, discloses a bipolar transistor in which a single p+ doped delta layer in an undoped gallium arsenide layer of 100 .ANG. thickness forms the base of a heterojunction bipolar transistor. Operating speed of the device is increased due to the thinness of the delta doped based layer.

Bipolar transistor having base region with coupled delta layers

The Board of Regents of the University of California


The invention relates to a stabilizing apparatus for a motor vehicle using a torsion bar for conveying torsional forces from one location on a motor vehicle to another location on a motor vehicle. A torsion arm with variable flex resistance along its length conveys forces from a wheel suspension component to the torsion bar. An engagement assembly is provided between the wheel suspension component and the torsion arm for selectively varying the engagement location of the suspension component along the length of the torsion arm as the vehicle moves. In this manner, the amount of leverage applied to the torsion bar can be varied, thereby changing suspension characteristics of the vehicle.

1. Field of the Invention
The present invention relates to an automotive suspension system including a torsion bar for providing roll and/or sway stabilization. The invention further relates to a system for varying the connection location of the torsion bar to a motor vehicle in order to selectively vary suspension characteristics of the vehicle.
2. Description of the Related Art
Torsion bars are used in vehicle suspension systems in various ways, most commonly as anti roll bars for resisting rolling and swaying motions that occur during vehicle movement. In addition, a torsion bar may be used in a vehicle as a spring to serve a weight bearing function. These functions are accomplished by connecting at least one end of the torsion bar to the suspension arm of a vehicle and either fixing the opposite end of the torsion bar to the frame of the vehicle or to another suspension arm of the vehicle.
Torsion bars are generally connected to vehicle suspension arms through a torsion arm extending from the torsion bar. By way of example, and as illustrated in FIG. 1, torsion bar 20 includes integrally formed torsion arms 22 and 24. The torsion bar 20 is rotatably connected to the underside of a vehicle 30 with sleeves 26 and 28. The distal ends of the torsion arms are connected to suspension arms 32 and 34 which in turn support the rear wheels of the vehicle 30.
FIGS. 2a-c, schematically illustrate three ways in which torsion bars may be used in a motor vehicle. In FIG. 2a, torsion bars are used to provide roll and sway resistance. In FIGS. 2b-c, the torsion bars are used to serve a weight bearing function. By way of example, the related art and the present invention will be hereinafter discussed in connection with the arrangement shown in FIG. 2a, which corresponds to FIG. 1. However, the present invention is not limited to this arrangement.
During cornering, the body of a vehicle has a tendency to roll towards the outside of the turn. When this occurs, the suspension arms at the outside of the turn become compressed toward the body of the vehicle while the suspension arms on the inside of the turn move away from the body of the vehicle. A torsion bar connected between the inside and outside suspension arms resists this motion by transferring forces from one side of the suspension system to the other, thereby resisting roll. For example, if the vehicle in FIG. 1 were to turn towards the left at high speed, the suspension arm on the right side of the vehicle would move in an upward direction causing the torsion bar to rotate counterclockwise. This would exert an upward force on the left rear suspension arm countering its natural tendency to move downward. Simultaneously, an upward force would be transmitted to the right side of the vehicle through rotatable mount 26 and a downward force applied through mount 28.
Torsion bars can be constructed of different materials such as spring steel, and in different sizes in order to provide an automobile with desired performance characteristics. For example, provided all other variables remain constant, the higher the torsion modulus of a torsion bar, the greater roll resistance that will be imparted to the automobile. High roll resistance enhances an automobile's steering performance, especially when the vehicle is moving at high speeds and on smooth surfaces. On the other hand, when the vehicle is traveling along rough and uneven surfaces, high roll resistance may decrease traction. In addition, on rough roads, even at slow speeds, a torsion bar with a high torsion modulus provides a bumpy and uncomfortable ride.
Thus, automobile manufacturers are often required to assess the trade-offs between torsion bars of high and low moduli of torsion, and usually have to make a compromise so that handling performance is acceptable under all road conditions. Of course, by making this compromise, handling performance can never be optimized under all road conditions.
In order to overcome this drawback of the prior art, attempts have been made to provide automobiles with torsion bars having selectively variable moduli of elasticity. For example, U.S. Pat. No. 4,796,991, describes a torsion bar split at its midpoint and having an adjuster disposed therebetween. The adjuster includes a chamber filed with magnetic fluid. When a magnetic field is energized, it causes internal friction in the magnetic fluid, thereby increasing the torsion modulus.
In U.S. Pat. No. 4,805,929, a control cylinder having a piston is connected between the wheel suspension of a vehicle and an end of an arm connected to the torsion bar. Fluid is supplied to the cylinder to lock the piston in a fixed position within the cylinder thereby providing stability through the torsion bar, or to permit the piston to move within the cylinder, effectively disengaging the torsion bar.
There are a number of drawbacks with the previously described related art systems. First, they are relatively complex and expensive to manufacture, and are therefore impractical from an economic standpoint. In addition, in the related art systems, if the electrical system of the vehicle fails while the suspension system is in a low stability mode, the suspension system may be prevented from returning to the high stability mode. This could create an extremely hazardous condition which could lead to the vehicle flipping over during a turn.

Variable rate torsion control system for vehicle suspension


The present invention is generally directed to a system, method and article of manufacture for modifying data represented abstractly through an abstraction model. In one embodiment, a data repository abstraction layer provides a logical view of an underlying data repository that is independent of the particular manner of data representation. A query abstraction layer is also provided and is based on the data repository abstraction layer. A runtime component performs transformation of an abstract query into a form that can be used against a particular physical data representation. The transformation includes ordering physical modification operations according to a physical entity relationships specification to ensure that the physical modification operations are executed in an appropriate order.

1. Field of the Invention
The present invention generally relates to data processing, and more particularly, to the modification of data through a logical framework.
2. Description of the Related Art
In commonly assigned U.S. patent application Ser. No. 10/083,075 (the '075 application), filed Feb. 22, 2002 entitled "Improved Application Flexibility Through Database Schema and Query Abstraction", a framework was disclosed for logically viewing physical data. The framework of the '075 application provided a requesting entity (i.e., an end-user or application) with an abstract representation of physical data. In this way, the requesting entity is decoupled from the underlying physical data to be accessed. Logical queries based on the framework can be constructed without regard for the makeup of the physical data. Further, changes to the physical data do not necessitate changes to applications accessing the physical data.
In addition to accessing abstractly represented physical data (i.e., issuing queries against the data to receive results), it is desirable to modify (i.e., insert, update and delete) data based on the abstract data representation. However, changing a data repository requires a significant amount of knowledge about the underlying database schema. In a relational database, modifications to the database must be performed on a single table basis and a detailed knowledge about the column formats and applicable values is necessary. To ensure data integrity, database modifications must account for relationships between database tables (such as primary key/foreign key relationships) and must account for requirements that tables be updated in a certain order. In the case of an abstracted database, the knowledge for dealing with such lower-level logical operations must also be abstracted. Otherwise, the knowledge must be accounted for at the application level, thereby undermining a primary advantage achieved by abstract representation of data.
Therefore, what is needed is the ability to modify data based on an abstract data representation.

Sequenced modification of multiple entities based on an abstract data representation

International Business Machines Corporation


A tie down for use on a load bearing surface includes a cup-shaped housing, a mounting block, a cylindrical fastener assembly, and at least one bail. The mounting block and cylindrical fastener assembly is rotatably mounted in the cup-shaped housing. The mounting block and cylindrical fastener assembly allow for rotation of the at least one bail above the plane of the load bearing surface.

The transport of cargo by a vehicle on land, in the air or over water typically requires temporarily securing the cargo to a substantially flat load bearing surface. This temporary securing of cargo to a substantially flat load bearing surface prevents the cargo from moving and effectively prevents the cargo from moving with respect to the vehicle. The process of securing cargo to a substantially flat load bearing surface typically involves the use of the straps, the ropes, the chains and the like. The straps, the ropes, the chains and the like are either attached to the cargo, passed over the cargo or passed around the cargo. Once the straps, the ropes, the chains and the like have been attached to, passed over, or passed around the cargo, the end of the strap, the rope or the chain is caused to be connected to a tie down secured to the load bearing surface. A more detailed description of such tie downs appears in MIL-STD-209K as all branches of the military are heavily involved in moving cargo each time military personnel and their equipment are deployed to various parts of the world.
Various different types of tie downs are currently available. U.S. Pat. Nos. 4,907,921; 5,052,869; and 7,134,819 are representative of prior art tie downs.
Makers and users of tie downs are continually looking for stronger, easier to use, easier to manufacture and less expensive tie downs. Accordingly, a need remains in the art for a tie down which is stronger, easier to use, easier to manufacture and less expensive than prior art tie downs.

System and method for securing cargo to a load bearing surface


Systems and methods for co-enhancing contaminant degradation such as LNAPL and DNAPL degradation. Embodiments of the inventive technology may relate to assuring adequate amounts (e.g., concentrations) of certain substances (e.g., nitrogen, electron acceptor, bacteria, microbial substrate) so that degradation of LNAPL and DNAPL is enhanced as intended. Any of the inventive methods may involve the amendment of groundwater with one or more particular substance (uric acid, electron acceptors, microbial substrate, as but a few examples) in order to enhance DNAPL, and perhaps also, LNAPL degradation.

The present inventive technology, in embodiments, includes enhancing light non-aqueous phase liquid ("LNAPL") degradation to accelerate dense non-aqueous phase liquid ("DNAPL") degradation; and perhaps even amending uric acid and uric acid-containing wastes as nitrogen sources in biodegradation of perhaps both LNAPL and DNAPL.
LNAPLs, including but not limited to gasoline, diesel, motor oil, and the like continue to be common contaminants in soils, groundwater, and the like. Bioremediation is an effective technique used in degrading LNAPL, which are converted into harmless by-products. Aerobic degradation dominates LNAPL remediation. In groundwater where oxygen is depleted, LNAPL can be biodegraded anaerobically by denitrification, iron reduction, and other microbial processes. Higher redox conditions are usually in favor of LNAPL biodegradation.
Dense non-aqueous phase liquids (DNAPLs), including but not limited to trichloroethene ("TCE"), are another type of contaminant found in groundwater and the like. Biologically catalyzed reductive dehalogenation may be a reducing process that reduces DNAPL to their final products. Reductive dehalogenation may occur under lower redox conditions, perhaps where acetogenesis, sulfidogenesis, methanogenesis and the like are dominant.
DNAPL (TCE and PCE, as but two examples) may be a major concern in groundwater contamination. These contaminants may transport rapidly down the vadose zone and end up in the groundwater. DNAPL tend to accumulate in bedrock, sediments or the like because of its high density and low water solubility. DNAPL may act as a source of groundwater contamination and may be recalcitrant to conventional remedial technologies. Reductive dehalogenation may be the most favorable bioremediation method for DNAPL clean-up in groundwater. As in LNAPL degradation, N nutrients may be a factor in shortage. However, conventional nitrogen amendments may have a very low efficiency for DNAPL degradation, possibly due to the high solubility of these amendments and the low solubility of DNAPL or for other reasons. This incompatibility may warrant a nitrogen source with relative DNAPL-affinity and time-releasing characteristics.
Enhanced bioremediation may overcome factors that may limit the rates of conventional pollutant biodegradation. Pollutant biodegradation may involve using enzymatic capabilities of indigenous microbes and perhaps modifying environmental factors such as oxygen, nitrogen, phosphorus, sulfur and electron acceptors concentration, as but a few examples. Nitrogenous ("N") nutrients, such as ammonium nitrate, ammonium sulfate, urea, ammonium chloride, sodium nitrate, and the like have been studied and may have been shown under various conditions to stimulate microbial activities and degradation rates in soil and groundwater systems. Ammonium (NH4+), as may be a preferred N nutrient released by these source compounds, may be readily consumed by aerobic microbes for amino acid formation and other metabolisms. Nitrate (NO3−) may be a preferred N nutrient, as well as an electron acceptor, for anaerobic microbes to degrade hydrocarbons via denitrification.
Some nitrogen amendments may be highly soluble in water and large amounts of N nutrients may be released in short periods of time. Highly soluble N nutrients may not be available to groundwater microbes of low populations. In addition, NO3− may be lost due to denitrification and chemical decomposition. Frequent reapplications of these quick-releasing nitrogen fertilizers could be necessary to maintain the satisfactory biodegradation of contaminants, which could drive up the operational cost.
A slow-releasing N fertilizer should have one or more chemical or perhaps metabolic pathways and should be relatively insoluble in water. Urea may be considered as a slow-releasing N fertilizer since it may undergo hydrolysis before ammonium can be released. However, urea may be highly water-soluble and may even be subject to leaching through soil and dilution in groundwater. There may be slow-releasing N fertilizers, such as sulfur coated or polyolefin coated urea and the like, that may be relatively insoluble and may release N much more slowly than urea does. Yet, they may be energy intensive to produce, possibly making them an undesirable alternative due the high cost.
As such, highly soluble nitrogen compounds may be less bioavailable for microorganisms that are responsible for reductive dehalogenation, possibly resulting in expensive and low efficiency biodegradation. Although the role of nitrogen in biodegradation of LNAPL may be well recognized, and it may be equally critical in the bioremediation of DNAPL compounds.
DNAPL, such as the chlorinated solvent TCE, is a group of common contaminants in soil and groundwater. DNAPL transport rapidly down the vadose zone into the groundwater, and accumulate in bedrock or sediments due to their high mass density and low water solubility. DNAPL is a group of groundwater contamination that is recalcitrant to conventional remedial technologies. Under anaerobic conditions, such as in oxygen-depleted groundwater, TCE can be reductively dechlorinated by pure or mixed bacterial populations to less chlorinated ethenes and eventually to ethane (Holliger et al, 1993; Krumholz et al., 1996; Sharma and McCarty, 1996; Maymo-Gateil et al., 1997). Reductive dechlorination has been widely applied as an effective technique in cleaning up chlorinated solvents. This technology resolves the difficulty of inaccessibility to contaminants, as in other mechanical and physical remedies. Biodechlorination of chlorinated ethenes have been studied under various anaerobic conditions (nitrate reducing, sulfate reducing, iron reducing, and methanogenic processes) conditions (Bagley and Gossett 1990; Boopathy and Peters 2001; Bouwer and McCartey 1983; DeBruin et al. 1992; Flierman et al. 1988; Freedman and Gossett 1989; Hardman 1991; Hoelen and Reinhard 2004; Krone et al. 1989; Ndon et al. 2000). In some studies, dechlorination has been reported to cease at cis-1,2-dichlorethene (cis-DCE) and vinyl chloride (VC) in the presence of sulfate (Bagley and Gossett 1990; Boopathy and Peters 2001; Ndon et al. 2000). Complete dechlorination of TCE to ethene has been reported under methanogenic conditions (Bouwer and McCartey 1983; De Bruin et al. 1992). In other laboratory and field studies, dechlorination of PCE and TCE was observed occurring under or associated with sulfate reducing conditions (Bagley and Gossett, 1990; DiStefano et al., 1991; Pavlostathis and Zhuang, 1993; Maymó-Gatell et al., 1999; Ndon, et al., 2000; Drzyzga et al., 2002; Hoelen and Reinhard, 2004).
LNAPL, such as diesel and motor oil, are usually co-existing with DNAPL like TCE, although not necessarily in the same groundwater zone. In the site under study, free and soluble phases of LNAPL and DNAPL have formed a "four phase" system in the groundwater. Since the favorable degradation conditions for LNAPL are either in the presence of oxygen or other "higher-redox" electron acceptors, such as nitrate, the redox conditions sustaining reductive dehalogenation of DNAPL are not supportive to LNAPL degradation.
Fuel hydrocarbons are a group of co-contaminants frequently co-existing with chlorinated ethenes. Under proper conditions, capable microbes utilize fuel hydrocarbons as the carbon source for their metabolisms, converting them into shorter-chained intermediates and/or final products of carbon dioxide. When oxygen is depleted, as in most groundwater systems, nitrate reduction has been reported to be the most favorable pathway for hydrocarbon degradation (Al-Bashir et al. 1990; Durant et al. 1995; Leduc et al. 1992; Mihelcic and Luthy 1988). Typically, biodegradation of hydrocarbons depletes both oxygen and nitrate, leading to sulfate-reducing conditions (Hoelen and Reinhard 2004). Some studies have reported efficient biodegradation under sulfate-reducing conditions (Canfield et al. 1993; Coates et al. 1997; Reeburgh 1983). Consumption of the fuel hydrocarbons by sulfate reducers can channel protons/electrons to dehalogenating bacteria (e.g., dechlorinating bacteria), and, at least in the case of degradation of TCE, reductive dechlorination may be completed without accumulating cis-DCE and VC.
Further shortcomings of conventional technologies relative to bioremediation include the absence of methods that efficiently address the problem of co-contamination, i.e., the case where groundwater is contaminated with LNAPL and DNAPL, perhaps in different zones. At least one embodiment of the inventive technology provides a method whereby the contaminated groundwater is measured relative to concentrations (molar ratio, population per volume, as but two examples) of certain substances (living and non-living things, such as nitrogen, phosphorus, electron acceptor and/or bacteria, as but a few examples), and such measurements can be used to determine whether an amendment (e.g., an addition of a certain substance, whether living or non-living) should be added to enhance degradation of both LNAPL and DNAPL contaminants.

Methods of enhancing biodegradation of groundwater contaminants

The University of Wyoming Research Corporation


An endoscope is provided that comprises an imaging device such as a micro-size video camera supported by a novel device-steering shaft assembly. The shaft assembly comprises a malleable or rigid shaft, an imaging device carrier releasably and pivotally supporting the imaging device at one end of the shaft, and operating means including a flexible operating cable and cable moving means attached to the opposite end of the shaft for moving said cable and thereby pivoting the imaging device carrier relative to the shaft so as to alter the viewing angle of the supported imaging device. Using a malleable shaft offers the advantage that the shaft is manually reformable into various configurations to facilitate access to different surgical sites, with the shaft having the ability to remain in each selected configuration until manually reformed into another configuration. Alternatively, the imaging device may be permanently attached to the device carrier. A routing configuration for the cable permits the imaging device to be rotated sufficiently to attain retrograde viewing. The endoscope may be converted to another instrument by replacing the imaging device on the device carrier with some other device such as a surgical laser, a magnetic sensor, an infra-red or other radiation sensor, an infra-red or other radiation transmitter, an ultrasonic transducer, or other surgical device such as a surgical scissors or a grasper.

1. Field of the Invention
This invention relates to device-steering shaft assemblies and instruments embodying same, more particularly to video endoscopes comprising device steering means which allow an operating physician to view surgical sites from different angles.
2. Description of the Prior Art
Endoscopes and borescopes, which are telescopic instruments used to inspect cavities or openings or other selected sites, have found a number of applications in medicine and other technologies. In the field of medicine, the use of endoscopes permits inspection of organs or tissue for the purpose of facilitating the obtainment of biological specimens or the viewing of a surgical site for the purpose of facilitating the manipulation of surgical instruments so as to avoid or minimize invasive and traumatizing surgical procedures.
Endoscopes generally comprise an insertion portion in the form of a tubular shaft that is designed to be inserted into a patient. Older conventional endoscopes used in medicine contain an objective lens unit at the distal (forward) end of the insertion portion which transmits an image of the area forward of the objective lens unit to a remote eyepiece for viewing by the surgeon, the image being transmitted to the eyepiece via an image-forwarding means in the form of a relay lens set, or an optical fiber bundle unit. In more recent years, in place of the eyepiece and at least part of the image forwarding means, it has been preferred to provide a small size solid state electronic video imaging device, such as one employing a CCD chip, in the imaging plane of the objective lens unit, and applying the output of that video imaging device via a suitable electronic transmission system to a video monitor for viewing by a user. The combination of an objective lens unit and a solid state video imaging device constitutes a video camera, and an endoscope that utilizes a video camera is known as a video endoscope. With both types of endoscopes, a surgeon can view the displayed image and use the information conveyed by that image to manipulate the endoscope and also other surgical instruments that have been inserted into the patient via the same or another incision or opening in the patient's body. Video endoscopes also may be of the stereo variety so as to provide depth perception. Stereo video endoscopes comprise optical means for generating first and second optical images, and video imaging means for generating first and second electrical signals in response to the first and second optical images respectively.
The present state of the art of endoscopes prior to this invention is demonstrated by the following U.S. patent applications and patents: (1) copending application Ser. No. 08/722742, filed Oct. 1, 1996 by K. Hori et al; (2) U.S. Pat. No. 5,538,497, issued Jul. 23, 1996 to K. Hori; (3) U.S. Pat. No. 5,582,576, issued Dec. 10, 1996 to K. Hori et al; (4) U.S. Pat. No. 5,603,687, issued Feb. 18, 1997 to K. Hori et al; and (5) U.S. Pat. No. 5,662,584, issued Sep. 2, 1997 to K. Hori et al; and the prior art cited in said application and patents. To the extent necessary, the teachings of those patent applications are incorporated herein by reference thereto.
Originally the insertion portion of endoscopes had a generally rigid tubular construction and the endoscopes looked straight ahead. However, soon variants were developed having fixed angular deviations from straight ahead viewing, typically 30.degree.. Subsequently, endoscopes with flexible tubular insertion portions appeared. Some of these flexible endoscopes can be remotely steered, such as by cables which cause the flexible shaft to bend. However, existing instruments of this type have limited angular deflection capabilities and limited minimum radii of curvature.
In so-called minimally invasive surgery, an endoscope is used to visualize the operating field inside a body cavity while the surgeon manipulates instruments therein so as to perform the surgical procedure.
New recently developed minimally invasive endoscopic procedures, such as thoracoscopy, are making greater demands upon endoscopic orientation than existing instruments can practically provide. For instance, it is becoming necessary to look sideways (i.e., 90.degree.) or even retrograde (approaching 180.degree.). In conjunction with the need for a larger range of viewing angle, there is also the requirement that the tip of the endoscope be positionable within the body cavity so as to take full advantage of the larger range of viewing angle. For instance, if it is desired to view an organ from behind--that is, to extend the endoscope beyond the organ and observe its hidden surfaces in retrograde fashion--then positioning the endoscope for this purpose may be impossible with a rigid, straight shaft endoscope or with currently available flexible shaft endoscopes. It would be helpful to the physician to be able to configure the insertion portion of the endoscope in a manner advantageous for entry and positioning relative to the surgical site, and have the endoscope maintain that configuration until changed by the physician. It also would be of value to be able to vary the orientation of the video camera in different situations without being restricted by the physical construction of the insertion portion. A further consideration of this invention is that many commercially available endoscopes have been designed for particular procedures and are not suitable for use in other procedures.

Device-steering shaft assembly and endoscope


A set-top electronics and network interface unit arrangement is connected to an internal digital network interconnecting devices in the home. The digital network operates on a single, nomodulated, baseband channel. Entertainment services are introduced into the network through network interface units that are coupled to an external network and to the internal network. The network interface units perform the necessary interfacing between the external and internal networks, and make the entertainment services available to all terminals connected to the internal network. Set-top electronics that are separate from the network interface units connect to the internal network and convert the information in the digital data stream for display, by a television, for example.

The present invention relates to multimedia digital networks, and more particularly, to set-top boxes for interfacing with external network and entertainment service providers and converting the received information for use or display by in-home products, such as televisions.
The rapid gains in digital technology and telecommunications have increased the desirability of having a network in the home to interconnect a multitude of products in the home with each other and to the outside world. The range of available outside services includes interactive services, cable video and audio services, satellite networks, telephone company services, video on demand, and other types of information services. However, penetration of the personal computer into homes in the United States is approximately 33% and only growing slowly, although governments desire more extensive penetration to encourage xe2x80x9ctelecommutingxe2x80x9d and reduce road traffic and pollution. Further penetration of computers in the home will originate from the purchase of consumer entertainment and informational products containing an embedded computer and operating system hidden by an opaque user interface. Such a product is a conventional set-top box.
Set-top boxes are multi-media computers that augment the use of televisions. A conventional set-top box has an external network interface module that connects the set-top box to the external network and data provider. The network interface module has to perform a number of sophisticated functions, such as interfacing to a specific external network, tuning, demodulation, error correcting, video descrambling, recovery of MPEG clock, and encryption and decryption specific to the external network. Consequently, the network interface module is a relatively expensive component of set-top boxes. This expense would be necessary when even a single television is present in the house. However, most homes contain multiple televisions, and providing each with its own set-top box and associated network interface module is a duplication of expensive components.
Another concern for homeowners is the issue of the service providers. Limitation to one service provider for all services introduced into the home through a set-top box, such as by a telephone provider, restricts the choices of a homeowner and possibly prevents the homeowner from obtaining services at the lowest competitive price. Attempting to overcome this problem with multiple service providers using a stack of multiple set-top boxes on every television in a home is not a viable solution.
There is a need for a set-top computer/audio/video/graphics electronics that with a television display forms an entertainment terminal and network interface arrangement in a single home to access the data from multiple external networks.
These and other needs are met by the present invention which provides an arrangement in which the set-top electronics that support the media output devices, such as televisions, are separate from the network interface units that interface to external networks. The separation of the network interface unit functions from the set-top electronics allows a single network interface unit to be used to interface with an external network and provide programming selectively to a multitude of set-top electronics and televisions within the home. This reduces the need for duplication of the network interface functions at each television or other end product. (media output device) and thereby reduces the costs for the typical homeowner who will have more than one television set in the home. Further, having multiple separate network interface units on the network allows the consumer to pick and choose among available services, and not be constrained to a single service provider. Changing a service may be performed simply by exchanging or adding a different network interface unit configured to interface with the new external network.
The foregoing and other features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.

Set-top electronics and network interface unit arrangement


A roof assembly for a vehicle roof having a roof opening may have a movable roof element for optionally closing and at least partially uncovering the roof opening, a strand-shaped sealing profile which is adapted on a sealing side for sealing against the movable roof element and can be fastened to a fastening side on the vehicle roof. The sealing profile may have a sealing tube which is elongated along a longitudinal axis (X) and which surrounds a hollow chamber, and a recess which extends transversely to the longitudinal axis (X) through the sealing tube, such that the fastening side is fluid-connected to a side of the sealing tube facing away from the fastening side.

A vehicle roof of a motor vehicle can have a roof opening which is closed, and optionally at least partially uncovered, by a movable roof element. For example, a seal is provided for sealing the vehicle roof with the movable roof element. This seal is intended to prevent water from penetrating into a dry area of the vehicle roof or of the motor vehicle.

Roof assembly for a vehicle roof having a roof opening


A computer-implemented method according to one embodiment includes identifying data stored within a first virtual storage tier of a storage system, analyzing one or more characteristics of the data, and conditionally transferring the data from the first virtual storage tier of the storage system to a second virtual storage tier of the storage system, based on the analyzing.

The present invention relates to data storage, and more specifically, this invention relates to determining a storage of data within a storage system based on data compression options available within the storage system.
Data storage is an essential part of modern computing practices. Data compression is often used to reduce an amount of storage space required for stored data within storage systems. However, current applications of compression are static and do not account for characteristic changes of stored data over time.

Tiering data compression within a storage system


A method for the production of a superconducting oxide tape having a Bi.sub.2 Sr.sub.2 Ca.sub.2 Cu.sub.3 O.sub.10 (Bi-2223) structure interposed between silver sheets, which method consists essentially of preparing a sandwich structure having interposed between silver sheets a molded layer of a superconducting oxide precursor powder consisting essentially of Bi, Pb, Sr, Ca, Cu, and O obtained from a raw material substance composed of, in atomic composition ratio, 1.00 of Bi, 0-0.2 of Pb, 0.9-1.1 of Sr, 0.9-1.1 of Ca and 1.3-1.7 of Cu, and O, heating the sandwich structure in an atmosphere consisting of oxygen and an inert gas, having an oxygen partial pressure in the range of 0-5%, and kept at a temperature in the range of 830-850.degree. C., thereby melting the molded layer, then causing the atmosphere to retain the heating temperature and meanwhile increasing the oxygen partial pressure, thereby inducing precipitation of crystal grains possessing a Bi.sub.2 Sr.sub.2 CaCu.sub.2 O.sub.8 (Bi-2212) structure and excelling in orientation, and subsequently maintaining the oxygen partial pressure and temperature at the time of precipitation of the crystal grains, thereby transforming the structure into the (Bi-2223) structure while retaining the particle diameter of the crystal grains and the state of orientation, and superconducting oxide tape produced by the method.

1. Field of the Invention
This invention relates to a method for the production of a superconducting oxide tape having a Bi.sub.2 Sr.sub.2 Ca.sub.2 Cu.sub.3 O.sub.10 (Bi-2223) structure and a superconducting oxide tape produced by the method.
2. Description of the Prior Art
Research concerning superconducting oxides has advanced remarkably in both basic and applied fields in recent years. In the basic field, numerous papers have been published regarding the discovery of superconductors of novel compositions, the development of new methods of synthesis, the elucidation of superconduction mechanisms, etc. In the applied field as well, research on applications has expanded over a broad spectrum of materials ranging from electric and electronic materials to therapeutic materials. In numerous fields expectations are high regarding the development of oxide superconducting materials and the exhancement of their functions.
Such nonoxide type superconducting materials as niobium titanium alloys are currently utilized extensively as superconducting substances. Superconducting magnets, exceeding 15 teslas in capacity, are being manufactured with such superconducting substances. Owing to their low critical temperatures, however, these superconductors must be kept cooled with liquid helium, at huge cost of refrigeration.
Some of the superconducting oxide substances have critical temperatures exceeding the critical temperature of liquid nitrogen. If they could be practically applied, they would immensely reduce the cost of refrigeration. Thus, research on utilization of superconducting oxide substances for power storage, power transmission, generation of strong magnetic fields, etc. is being actively promoted. To realize such applications, it is necessary to reduce the superconducting oxide substances to wire rods or tapes.
The superconductor of the Bi.sub.2 Sr.sub.2 CaCu.sub.2 O.sub.8 (Bi-2212) structure, one of the Bi type superconductors, is manufactured by the partial melting technique into a tape which exhibits a very high critical current density in liquid helium. The present inventors earlier developed an improved method of producing a tape of the Bi.sub.2 Sr.sub.2 CaCu.sub.2 O.sub.8 structure based on the method mentioned above and a patent application has been filed thereon (U.S. patent application Ser. No. 08/873,090 which issued as U.S. Pat. No. 5,846,910). Their invention relating to the production of a superconducting polycrystalline wire rod from superconducting whiskers of the Bi.sub.2 Sr.sub.2 CaCu.sub.2 O.sub.8 structure has also been applied for patent (U.S. patent application Ser. No. 08/873,084). Since the critical temperature of the Bi-2212 superconductor is 80-90 K, only slightly different from the temperature of liquid nitrogen, the Bi-2212 superconducting oxide tape is hard to use at the temperature of the liquid nitrogen.
The wire rod of the Bi-2223 superconductor, which has a critical temperature as high as 110 K, has therefore been attracting attention. So far, the partial melting technique has not yet succeeded in producing a wire rod of the Bi-2223 superconductor. The Bi-2223 superconductor wire rod is almost always obtained by the solid-phase sintering technique. Since the Bi-2223 superconductor wire. rod is a polycrystalline substance, the factors thereof such as the intensity of superconducting bond at the grain boundary and the particle diameter of crystals directly affect the critical current density. Specifically, the critical current density rises as the strength of bond at the grain boundary and the size of crystal particles increase. Since the superconductor wire rod produced by the solid-phase sintering technique is limited as regards the superconducting bond intensity and the crystal particle diameter, the improvement thereof in critical current density is likewise limited.
It is the main object of this invention to provide a practical method for the production of a Bi-2223 superconducting oxide wire rod or tape by the partial melting technique.

Method for production of superconducting oxide tape and superconducting oxide tape produced thereby

Agency of Industrial Science & Technology, Ministry of International Trade & Industry


An improved worm drive clamp comprised of a flexible metal clamping band and a housing containing a tightening screw is secured to one end of the band. The tightening screw is axially and angularly displaceable within the housing for engagement and disengagement from an engageable free end of the band which is passed through the housing to form a band loop for securement about an object. The housing is comprised of opposed guide channels through which opposed edge portions of the free end portion of the band is caused to pass to position the free end portion in a fixed arcuate plane for engagement and disengagement with the displaceable tightening screw which is located thereabove in a screw retention portion of the housing. The tightening screw pivots in a slot formed in an end wall of the housing and displaced outwardly in a further slot formed in the opposed end wall of the housing. The housing is also formed from a unitary metal piece.

In my previous U.S. Pat. No. 4,993,124 issued on Feb. 19, 1991, I disclose a worm drive clamp of a construction wherein the free end portion of the flexible metal clamping band is spring-biased against a tightening screw which is axially rotatable on a fixed axis. The advantages of being able to insert the band through the housing without engagement with the threaded screw is disclosed therein. Another advantage is to easily and quickly insert the free end portion of the band within the housing and providing engagement of the screw only after the band has completely encircled the object which is to be secured thereto. This desirable feature provides for the clamp to be quickly connected and disconnected from an object.
The present invention is directed to a worm drive clamp of the type wherein the tightening screw is hingeably secured within the housing and can be hinged out of engagement with the free end portion of the band. Such clamps are known in the art, such as that described and shown in U.S. Pat No. 2,825,113 issued on Mar. 4, 1958 and U.S. Pat. No. 4,445,254 issued on May 1, 1984. As described in these patents the tightening screw is displaceable both in the axial direction and upwardly away from the free end portion of the band which is passed through the housing. A disadvantage of these clamps is that the tightening screw provides obstruction to the free end portion of the band when inserted in the housing. When the band is inserted in the housing it moves upwardly towards the screw due to the arcuate shape of the band and also due to the fact that the passage provides for the band to spring upwardly therein. In other words, the band enters one end of the housing and out the other without any guided restriction between the opposed ends of the passage. This is due to the fact that the screw has to move upwards and downwards in the housing. The construction of these clamps also makes it very difficult to restrict the passage of the band within the housing. Accordingly, many of these types of clamps have not achieved commercial success. These clamps also have various component parts and are difficult to assemble, and often resulting in malfunction.
U.S. Pat. No. 4,307,495 discloses a housing with opposed guide channels for positioning the free end portion of a flexible band in contact with a tightening screw. However, such is difficult and complex to manufacture, and the screw is maintained at a fixed position. Such complexity becomes compounded when the bottom wall of the housing has an arcuate shape.

Worm drive clamp with band guide channels


A modem includes a dynamic host configuration protocol (DHCP) module, a point-to-point protocol over Ethernet (PPPoE) module, and a network monitor module. The DHCP module automatically establishes a DHCP connection over a communication network, and generates a first notification signal after the DHCP connection is established. The PPPoE module automatically establishes a PPPoE connection over the communication network and automatically configures parameters of an Internet access service over the communication network and generates a second notification signal after the PPPoE connection is established. The network monitor module determines current network properties of the communication network upon receipt of the first notification signal and/or the second notification signal, and selectively configures parameters of the Internet access service and a voice over Internet protocol (VoIP) service.

1. Technical Field
The disclosure relates to communication devices, and particularly to a modem and configuration method thereof.
2. Description of Related Art
Terminal devices, such as computers and voice over Internet protocol (VoIP) phones, communicate with the Internet or other communication networks via modems, which are usually provided by service providers. However, different service providers provide different network properties and services. Network properties include pure dynamic host configuration protocol (DHCP) to provide VoIP services and Internet access services, pure point-to-point protocol over Ethernet (PPPoE) to provide VoIP services and Internet access services, and co-deployed DHCP and the PPPoE at the same time to provide VoIP services and Internet access services.
A modem must thus be preset with different network configurations before use. When network properties of a modem are changed, the modem needs to be reconfigured, presenting inconvenience to a user.

Hong Fu Jin Precision Industry (ShenZhen) Co., Ltd.


In one embodiment, an endoscopic camera for a robotic surgical system includes a stereo camera module mounted to a robotic arm of a patient side cart. The optical and electro-optic components of the camera module are hermetically sealed within a first housing. Signals from an electro-optic component travel through traces in a ceramic substrate forming one side of the hermetically sealed first housing. A second housing surrounds the first housing and optical fibers are dispersed between the housings to provide lighting in a body cavity. The camera module may be sterilized by an autoclave.

Minimally invasive medical techniques are aimed at reducing the amount of extraneous tissue that is damaged during diagnostic or surgical procedures, thereby reducing patient recovery time, discomfort, and deleterious side effects. The average length of a hospital stay for a standard surgery may also be shortened significantly using minimally invasive surgical techniques. Thus, an increased adoption of minimally invasive techniques could save millions of hospital days, and millions of dollars annually in hospital residency costs alone. Patient recovery times, patient discomfort, surgical side effects, and time away from work may also be reduced with minimally invasive surgery.
The most common form of minimally invasive surgery may be endoscopy. The endoscopic surgical instruments generally include an endoscope (for viewing the surgical field) and working tools. In endoscopic surgery, the working tools are similar to those used in conventional (open) surgery, except that the working end or end effector of each tool is separated from its handle by an extension tube. As used herein, the term end effector means the actual working part of the surgical instrument and can include clamps, graspers, scissors, staplers, and needle holders, for example.
To perform endoscopic surgical procedures, the surgeon passes these working tools or instruments through the cannula sleeves to an internal surgical site and manipulates them from outside the abdomen. The surgeon may monitor the procedure within the internal surgical site by means of an endoscope, also referred to herein an endoscopic camera. Minimally invasive surgeries where an endoscopic camera is used are well known (e.g., arthroscopy, retroperitoneoscopy, pelviscopy, nephroscopy, cystoscopy, cisternoscopy, sinoscopy, hysteroscopy, urethroscopy and the like).
After each surgery, federal and state health regulations require that surgical tools be treated to prevent infection. Surgical tools that are to be reused are often cleaned, disinfected, and then sterilized after use in a prior surgery. Surgical tools may be cleaned with water, an enzymatic cleanser, and a scrub brush. Common methods of disinfecting surgical tools involves bathing them in a chemical disinfectant so that the surgical tool can be passed around within a hospital with a low level risk of infection. However, after being disinfected, a surgical tool shouldn't be used for surgery as not all bacterial has been killed. A surgical tool that is to be reused in another surgery should undergo a further sterilization process where all bacterial are killed so that the tool can be used again for surgery without transmitting bacteria from one patient to another. The sterilization process involves either a chemical sterilization using chemical sterilization techniques or a steam sterilization process using an autoclave.
Disinfection and sterilization by immersion in a chemical liquid may not be as environmentally friendly. Disposal of the used chemical is costly and may cause harm to the environment. Another drawback is that the chemicals are generally corrosive. Furthermore, chemical disinfection and sterilization may be slower than other methods. Thus, a surgical instrument may have greater lag time between surgeries.
Similarly, disinfection and sterilization using chemical gases such as ethylene oxide also have their drawbacks. Such gases are highly toxic and/or flammable. Extreme care must be used during and after the disinfection and sterilization process to ensure the safety of both the patient and medical staff. Disinfection and sterilization using gases may be complicated. A surgical instrument may have greater lag time between surgeries.
Almost all medical facilities have an autoclave and prefer to use steam sterilization of surgical instruments when they can. Commonly known as autoclave sterilization, this method of sterilization rapidly and effectively sterilizes surgical instruments without toxic chemicals and lengthy procedures. Autoclaving standards vary but two common standards require 134 degrees centigrade (C) at 2 atmospheres for 3 minutes (U.S. Standard) and 134 degrees Celsius at 2 Atmospheres for 18 minutes (European Standard). Autoclaving requires less time than other disinfection methods and does not require the use of toxic chemicals. However, some surgical instruments can't tolerate the heat and moisture from steam sterilization in an autoclave.
The steam from autoclaving may cause conventional endoscopes to fail. Pressurized steam may damage the adhesives, optics, electronics, focusing mechanisms, and opto-electronics (e.g., image capturing circuit). Moisture in the endoscope may also condense on a lens and blur images. The adhesive mount for the lens of an endoscope may be adversely affected by the heat and moisture of an autoclave. A stereoscopic lens system is especially susceptible to autoclave damage, because the relative alignment of the right and left lenses (optical paths) is important to rendering depth in the stereo image. Heat deformation of a lens mount due to thermal expansion effects may alter the relative alignment of the stereoscopic lenses.

Stereo camera for hermetically sealed endoscope


Smart glasses are provided in the present disclosure, including a housing, a fixing bracket, a left lens barrel, a right lens barrel, an object distance adjustment mechanism including a left-eye object distance adjustment gear, a right-eye object distance adjustment gear, an object distance adjustment driving gear engaged with the left-eye object distance adjustment gear and the right-eye object distance adjustment gear and a driving motor driving the object distance adjustment driving gear to rotate and being capable of moving back and forth on the fixing bracket along a second direction; a pupil distance adjustment mechanism connected to at least one lens barrel, and configured to drive the lens barrel to move in the first direction when an external force is applied, and a linkage member arranged between the at least one lens barrel and the driving motor.

A pair of Virtual Reality (VR) glasses is a virtual reality head-mounted display device, and configured to shield a vision and an auditory sensation of a user to the outside, and guide the user to have a feeling of being in a virtual environment. When a pupil distance of the user does not match a distance between center points of a left lens and a right lens of the VR glasses, a discomfort sense may occur to the user. Therefore, the VR glasses usually have a pupil distance adjustment function in order to be suitable for different users. Similarly, in order to match different myopia degrees of users, it is necessary for the VR glasses to have an object distance adjustment function.
In single-lens VR glasses, a screen is usually moved during an object distance adjustment, glasses are merely required to be moved during a pupil distance adjustment, and the object distance adjustment may be realized by using one motor in structure. In contrast, in VR glasses with dual screens and dual lens barrels, it is difficult to achieve the object distance adjustment of the dual lens barrels driven by a single motor during the pupil distance adjustment. Usually, two motors are required to adjust object distances of the left and right lens barrels respectively. However, such problems as an increasing entire power consumption, a reducing battery life and an increasing control cost may occur by providing the two motors.

Smart glasses including object distance adjustment driving gear

BEIJING BOE OPTOELECTRONICS TECHNOLOGY CO., LTD.


A continuous mixer for liquids comprises a casing having a conical interior surface and a discharge outlet at the apex of the cone formed by the conical interior surface, a rotor that rotates at its center on the axis of the cone and has a conical exterior surface whose vertical angle is approximately equal to the vertical angle of the conical interior surface, a pressure-transport device that has one or more feed lines which communicate with a gap between the interior surface of the casing and the exterior surface of the rotor a position removed from the discharge outlet and that delivers one or more liquid inputs under pressure through the feed lines, and a gap-adjustment device capable of axially adjusting the rotor within the casing to adjust the gap. The internal pressure and temperature or the mixer can be controlled or adjusted while the rotor is rotating by changing the gap width along the axial direction.

This invention relates to a continuous mixer for liquids that can continuously mix a single incoming liquid or two or more incoming liquids.
The continuous mixing of one or more liquid stocks is widely practiced in the rubber molding industry and plastic molding industry. An example of this is the mixing of a base and curing agent in order to fabricate a foamed gasket.
For example, Japanese Patent Publication (Kokoku) Number Sho 53-15942 (15,942/1978), "Nozzle for mixing fluid components", teaches a nozzle for mixing a plurality of fluid components that react upon mixing with a rapid increase in viscosity or else cure upon mixing. The nozzle taught in this reference comprises a housing with a conical interior surface and a conical rotor that is rotated at its center on the axis within said housing. The surface of the rotor is provided with concavities, fins, and grooves. This nozzle can continuously mix a plural number of reactive fluid components in the absence of solvent.
The "Resin extrusion apparatus having a rotating conical element" disclosed in Japanese Patent Application Laid Open (Kokai) Number Hei 2-43008 (43,008/1990) comprises a rotating element whose exterior surface is a conical surface and whose rotational axis is the central axis thereof and a fixed element having a conical interior surface that faces the aforesaid rotating conical surface across a narrow gap. The design is such that rotation of the rotating element causes resin raw materials to be mixed in and extruded through the gap between the conical surfaces of the rotating and fixed elements.
The "Method for fabricating foam gaskets" disclosed in Japanese Patent Application Laid Open (Kokai) Number Hei 3-94876 (94,876/1991) employs a mixing chamber that is equipped internally with a surface-grooved rotating element and that has a nozzle formed at its bottom. The two liquids making up a two-part foamable plastic (the base and curing agent) are separately transported into this mixing chamber and mixed therein, and the resulting liquid mixture is discharged from the nozzle onto the sealing region of the particular substrate.
The "Apparatus for preparing silicone foam" of Japanese Patent Application Laid Open (Kokai) Number Hei 6-99509 (99,509/1994) solves a problem occurring with Japanese Patent Application Laid Open Number Hei 3-94876 in that the interior of the mixing chamber and nozzle element of the applicator must be cleaned with solvent after each application cycle. In the former a preheater is provided on the circumference of a liquid delivery hose that runs from the mixer to the discharge nozzle.
Several means have been employed or attempted in prior art apparatuses for continuously mixing liquids in order to control the temperature and pressure within the mixer during mixing into prescribed ranges or control the size of particulates within the mixed liquid. These means include:
(1) installation of a thermal medium jacket on the casing of the mixing apparatus and adjustment of the temperature and flow-rate of the thermal medium in the jacket (thermal medium control); PA0 (2) adjustment of the rotation rate of the rotor in the mixing apparatus (rotor rotation control); PA0 (3) pressure control through installation of a throttle on the mixed liquid outlet from the mixing apparatus (throttle control); and PA0 (4) adjustment in the input feed amounts (input flow-rate control).
These prior art means described above suffer from various problems. Temperature control by thermal medium control (1) has a poor response. In the case of rotor rotation control (2), a change in rotor rpm ends up causing a change in the intensity of mixing imparted to the mixing inputs. In the case of throttle control (3), the installation of a throttle at the outlet increases the resident amount of the input. The drawback to input flow-rate control (4) is that variations in the material feed also affect upstream and downstream processes. Moreover, a rapid response and high accuracy are required in order to regulate the internal temperature and pressure in the mixer in particular when a rapid chemical reaction is produced upon mixing (for example, in the case of curing by reaction). However, the prior art technologies are unable to satisfy this requirement. Another drawback to the prior art technologies is that they cannot regulate the particle size within the mixed liquid when the liquid input contains particulate.
The present invention was developed in order to solve the various problems described above. Specifically, the object of the present invention is to provide a continuous mixer for liquids that can continuously mix a single or several liquid inputs and that is capable of a highly responsive and very precise control of the temperature and pressure of the mixed liquid afforded by the liquid input. Another object of the present invention is to provide a continuous mixer for liquids which can control the temperature and pressure of the mixed liquid produced from the liquid input, which does not cause variations in the intensity of mixing of the mixed liquid, which minimizes the resident amount of the inputs, and which has little effect on upstream and downstream processes. A further object of the present invention is to provide a continuous mixer for liquids that can regulate the particle size in the mixed liquid from the liquid input in combination with regulation of the temperature and pressure.
The aforesaid objects are achieved by having the rotor of a continuous mixer assume the form of a cone or truncated cone centered on the axis of rotation with the mixed liquid discharge side at its vertex; having the interior surface of the casing of the mixer assume the form of a truncated cone that matches the shape of the rotor; setting the vertical angle of the truncated cone casing equal to or not substantially different from the vertical angle of the rotor; axially displacing the rotor or casing along the rotation axis; and thereby adjusting the gap between the rotor and casing.

Continuous mixer for liquids with rotor and casing gap adjustment


An image recording device includes a pressing force adjusting mechanism that adjusts a pressing force of a developing roller that is provided by an elastic member, against a photoconductive drum. This provides for modification and adjustment of the pressing force of the developing roller that is pressed against the photoconductive drum by the biasing force from the elastic member. Consequently, even where the developing rollers have various radius dimensions or where elastic force of the elastic member changes, adequate pressing force depending on each case can be applied to the developing roller, thereby improving the recorded quality of the image recording device.

1. Field of the Invention
The present invention relates to an image recording device arranged to conduct a recording process for an image forming apparatus such as a copier, a facsimile machine, a printer and a multifunction peripheral, particularly, to technology used to adjust a pressing force of a developing roller against a photoconductive drum.
2. Description of the Related Art
One of the substantive problems found in these image recording devices is deterioration in the image quality of a recorded image, which deterioration is caused by such change as making a pressing force of a developing roller large or small against a photoconductive drum. That is, aging and the like changes a biasing force of an elastic member arranged to press a developing roller against a photoconductive drum so that the previously-mentioned pressing force may be changed to deteriorate, the image quality of the recorded image. In addition, also in a case where developing rollers have variations in their diameters, the pressing force may change.
This problem becomes apparent in a case where a developing roller is replaceably configured. That is, this problem becomes apparent in a configuration where a toner agitating member and a developing roller are integrated as a developing unit so that the developing unit is replaced to replace the developing roller. This is because, in addition to such a factor as a change of biasing force of an elastic member variation in a structure for mounting a developing unit on a photoconductive unit, there is also a factor for changing the pressing force. In particular, a configuration in which developing unit is configured to be removably/rotatably mounted onto a coupling axis arranged between the photoconductive unit and the developing unit, worsened by complicated mounting structure, easily changes the pressing force when the developing unit is replaced.
Therefore, for example, an image forming apparatus disclosed in Japanese Unexamined Patent Application Publication No. 2011-102908 arranges a pressing unit arranged to press a developing unit against a photoconductive unit in a developing-device-housing unit arranged therein. That is, Japanese Unexamined Patent Application Publication No. 2011-102908 discloses a configuration arranged to press a developing unit against a photoconductive unit by using a pressing unit in an image forming apparatus which configures the developing unit to be removably and rotatably mounted on a coupling axis arranged between the photoconductive unit and the developing unit as described above. The pressing unit includes a cylindrical member, an elastic member arranged in the cylindrical member, and a movable member arranged to be moved in the cylindrical member by receiving a biasing force of the elastic member. By pressing the developing unit against the photoconductive unit by the biasing force of the elastic member, the developing roller can be arranged at a more precise position against the photoconductive drum.
However, the pressing unit according to Japanese Unexamined Patent Application Publication No. 2011-102908 cannot adjust the pressing force of the developing roller against the photoconductive drum at all. Consequently, in a case where the biasing force of the elastic member is changed or where the dimensions of the developing rollers are different, as mentioned above, the developing roller cannot be pressed against the photoconductive drum with an appropriate pressing force so that the image quality of the recorded image may deteriorate.


A method and apparatus for loading a film cartridge in a camera frame having a cartridge chamber, a supply chamber, and a thumbwheel extending into the cartridge chamber. The film cartridge has a case, an internal spool, and a filmstrip attached to the spool. In the method, the film cartridge is positioned in the cartridge chamber with the spool axially adjoining the thumbwheel. A quill is placed in axial proximity to the spool of the film cartridge, opposite said thumbwheel. The quill is turned in a rewind direction for the spool. Rotating of the spool in the rewind direction is deterred. During the turning, the quill is urged into axial engagement with the spool and the spool is urged into axial engagement with the thumbwheel. Following the urging, a leading portion of the filmstrip is thrust out of the cartridge.

Single use cameras are commonly sold preloaded with a cartridge of film. In order to reduce complexity and costs, a rewind mechanism is omitted from the camera. Instead, the film is prewound and during use is advanced back into the film canister. A number of approaches have been followed in loading and prewinding film cartridges for single use cameras. In some approaches, such as one taught in U.S. Pat. No. 4,972,649; film is prewound into a roll outside the camera body and then loaded. A shortcoming of these approaches is that the film roll must be handled after it is formed. This presents a risk of film damage and may add complexity to necessary equipment. In some other approaches, also taught in U.S. Pat. No. 4,972,649; the cartridge is loaded, the camera is light-tightly closed, and the film is then prewound. In still other approaches, such as taught by U.S. Pat. No. 5,311,231; the cartridge is loaded and then the rear opening of the camera body is closed and the film is prewound through a bottom opening, which is later sealed. The latter two approaches have the shortcoming that film guiding is provided primarily by the camera body, rather than loading apparatus. This places constraints on the camera body in terms of required tolerances and the like and may, in addition, slow throughput speeds. Still another approach is taught by Japanese Kokai 6-295022, European Patent Application No. 0743546-A, and Japanese Kokai 8-171180. In this approach, the film is wound onto a second spool, rather than being wound into a film roll. The back of the camera is not mandatory for guiding the film, since the second spool tends to restrain the film.
A number of separate procedures have to be performed to load a film cartridge into an incomplete camera and prewind the filmstrip. Bi-directional and unidirectional motion can be provided to various parts by separating procedure steps and necessary tooling. On the other hand, it is desirable to integrate procedural steps and necessary tooling to minimized wasted motion and reduce costs.
It would thus be desirable to provide cartridge loading apparatus and methods which allow both bidirectional filmstrip motion and unidirectional thumbwheel motion within a camera frame assembly.


The invention relates to carrier shells which can eject a payload in flight. A carrier shell for transporting a payload includes a body closed at one of its ends by a base and at the other by a head, inside of which is placed a pyrotechnic composition for generating gases intended to act on a piston at the time the payload is ejected. The shell includes an attachment between the piston and the shell after ejection of the payload. This invention is applicable to mine-dispersing carrier shells.

The technical field of this invention is that of carrier shells carrying a payload, for example one or more submunitions, and ejecting said payload in flight by means of a piston pushed by gas pressure.
Such a shell contains, in a known manner, a body provided at the rear with a band. A head and a base are threaded onto the front and rear ends, respectively, of the body. The interior of the body has a payload composed, for example, of at least one submunition. Housed in the tip of the head is a dispensing charge that can be ignited by a fuze.
Upon expiration of a time that is programmed before firing, the fuze ignites the dispensing charge which causes a gas pressure. The latter axially pushes a piston, which displaces the payload and the base in order to eject them from the shell.
One such type of carrier shell is described, for example, in French patent FR 2,363,077.
These carrier shells pose problems in terms of separation between the payload and the piston.
Specifically, the piston must decouple from the payload after ejection of the payload, but without disturbing its trajectory.

Carrier shell ejecting a payload by means of a piston


An apparatus for buffering or temporarily storing articles is disclosed. The apparatus includes a feed for the articles with at least one endless flexible member moving past the feed. Doglike elements which engage the articles and between which the articles are transported are movable together with the flexible member. One or more guide members for guiding the flexible member during changes of direction are provided with a discharge for discharging an article from between two doglike elements. A mechanism for diminishing the impact to the articles is provided wherein the guide members are movable relative to the feed and/or discharge.

Buffer or collating apparatus arranged in packaging lines for example for bars of chocolate and the like are known--see for example the German patent application 3724839--and have the object of discharging with regular mutual spacing articles that are supplied with at least slightly irregular mutual spacing.
In the known buffer apparatus problems occur particularly in respect of damage to these articles by sudden changes in movement of dogs and/or impacts against such dogs.
The present invention has for its object to improve the known buffer apparatus and/or obviate the above stated problems.