An offshore aquaculture system for use with an oil or gas well production platform or like offshore structure is provided. The platform is preferably supported in four (4) directions by radially extending guy wires that attach to the upper end of the platform at one end of each wire and to the seabed at anchor piles at the other end of each wire. Anchor piles are driven into the seabed a substantial distance to provide anchorage for the undersea end of each guy wire. Fish pens are mounted to slide and travel on the diagonal guy wires and can be elevated or lowered relative to the seabed using ballast tanks attached to the fish pens and an endless winch line. The winch line is operated with a powered winch mounted on the platform deck. An opposed idler sheave is mounted at the seabed engaging the endless cable.

1. Field of the Invention
The field of the invention relates to aquaculture and mariculture systems and more particularly relates to an improved method and apparatus for raising and harvesting fish in an offshore environment wherein a relatively soft seabed of mud exists. The present invention further relates to an improved method and apparatus for raising fish adjacent an offshore platform wherein at least one and preferably a plurality of opposed diagonal support guy wires extend between the platform and an undersea anchor pile, wherein individual fish pens or cages can be quickly transported along the diagonal guy wires with a winch line (eg. an endless winch driven cable) aided by ballast tanks on the cages. Even more particularly, air and food are transmitted to the cages via flexible flow lines that travel with the cages as they move into selected undersea depths, such as to avoid storms and undesirable water quality zones.
2. General Background
In the Gulf of Mexico, excellent conditions exist for raising many species of saltwater fish in an aquaculture or mariculture environment. However, the Gulf of Mexico experiences drastic changes in both weather conditions and in water quality.
One of the common problems with water quality in the Gulf of Mexico is the presence of hypoxic (low dissolved oxygen) or "dead zones" that are not suitable for aquatic life. These hypoxic zones have been associated with the flow of water from various large rivers such as the Mississippi, the Atchafalaya River, and others. Temperature usually varies with water depth. Some species of saltwater fish need warmer water for example in winter months. Another problem that exists with fish farming or mariculture in the Gulf of Mexico is the existence of frequent thunderstorms that generate high winds and heavy seas. These thunderstorms can be an almost daily occurrence in the summer months. They occur with very little warning and can generate high winds and seas of 8-10 feet or more. Such seas are potentially destructive to any type of pen or cage that is used to contain fish as part of a mariculture operation.
If a fish pen or cage is of a substantial size, it requires substantial anchorage to support it in a desired position. This is another problem that plagues the concept of mariculture in the Gulf of Mexico. The seabed in the Gulf of Mexico is soft mud, and it is weak structurally. Therefore, the anchorage of substantial fish pens or cages is a problem considering the unconsolidated nature of the seabed.
Many mariculture and aquaculture systems have been patented wherein cages or pens are provided in a marine environment.
A lobster cage arrangement is seen in the MacDonald U.S. Pat. No. 3,499,421. The patent discloses the use of a plurality of piling driven into a seabed to support cages.
The Gollott U.S. Pat. No. 4,266,509 discloses an offshore habitat for shellfish. The apparatus includes an open framework enclosure and defines a plurality of laterally spaced side by side sets of vertically spaced elongated horizontal cavities open at one set of corresponding ends. At least one open top tray is slidingly removably received in each of the cavities through the open ends thereof and the upper portions of corresponding adjacent cavities of adjacent sets of cavities are horizontally communicated and the upper and lower portions of adjacent vertically spaced cavities are in direct communication with each other. The trays include foraminated bottom, side and end walls and the enclosure defines structure for preventing movement of the trays between corresponding laterally spaced cavities, outwardly of the remote sides of the endmost cavities and outwardly from the ends of the cavities remote from the open ends thereof. Further, structure is provided for releasably lockingly retaining the trays within the enclosure against removal from the open ends of the cavities and the trays are sufficiently closely vertically spaced to prevent natural shellfish predators from entering the trays.
A modular cage system for underwater use is disclosed in the Mickelsen U.S. Pat. No. 4,337,727. A vertical housing and feeding structure is provided for raising mariculture and other underwater animals. Tiers of feeding tubes, each of a successively longer length, form a backbone structure to which cages may be selectively connected. Each cage is connected along a vertical front face of the backbone structure so that one of the feeding tubes terminates at a point accessible from within the cage. A feed opening just above this termination point directs food material dropped through the feeding tube to either fall within the cage or be accessible from therewithin so that it may be consumed by the caged animal. All of the feeding tubes of each tier have a top open end that is positioned near the surface of the water to facilitate the controlled delivery of food to each individual cage. Two sets of backbone structure may be joined back-to-back so that cages may be connected to both sides of the structure, thereby doubling the cage capacity of the system. The capacity of the backbone structure may also be augmented by increasing the width of the tiers of feeding tubes or by adding additional tiers of feeding tubes to the back of each bone structure, each additional tier being of a successively longer length. Either method thus increases the frontal area of the backbone structure and provides additional frontal space to which additional cages may be attached. Inspection of the cages is facilitated by hoisting the entire backbone structure, including the cages attached thereto, out of the water. The walls of the cages are screened with a sufficiently large mesh to allow oxygenated water to freely circulate therethrough and to further allow fecal material and uneaten food to fall out of the cage without accumulation.
The Bourdon U.S. Pat. No. 4,716,854 provides an open sea aquaculture installation that comprises a central structure similar to an offshore drilling platform and several floating modules which are anchored to the seabed. The different modules are disposed at a distance, determined perpendicularly between lines each crossing a module and parallel to the mean direction of current in the surface layer of the sea, sufficient so that dejecta from the different modules do not interfere with adjacent modules.
An aquatic net pen and method is disclosed in U.S. Pat. No. 4,982,697. The pen has a light weight inexpensive net cover for the top which keeps predators out. The cover is easy to apply and remove and yet is held securely in place by means of studs or posts extending upwardly from the frame of the cage or pen and having enlarged heads which preferably are slightly larger than the holes in the mesh. Preferably the mesh is made up of resilient plastic strands which snap back into tier original shape after being deformed by the bolt-heads passing through, so that the bolt heads and the netting together form a snap-fitting fastening system. In one embodiment, panels of materials such plastic netting are suspended in cages so as to attract the growth of algae thereon for feeding algae-eating aquatic animals such as conch, fish, etc. in the cages. The panels are formed into a removable unit so that some of the units can be suspended in water elsewhere and transferred to the cage to replace units from which the algae has been depleted, thus feeding the aquatic animals by merely replacing algae-depleted units with algae-loaded units.
Various foreign patents have issued which relate to underwater farming of marine animals. A French Patent 2627-951-A concerns an underwater farm for the study of marine life. The farm consists of four (4) concrete blocks which are mounted on a metal frame that is anchored to the seabed. Each concrete block is formed with a large number of holes and recesses to provide shelter for small fishes from predators. The blocks also provide a base for the growth of marine vegetation. The blocks are connected to a research station on the shore by means of a pipe or umbilical cord, through which suitable food can be pumped to the blocks. An underwater television camera enables the marine animals to be observed from the shore station.
A Russian Patent SU 1405-747-A discloses a growing plant for sea organisms. The apparatus includes vertical supports arranged in two parallel rows and a supporting element with frame is located between the supports. The supporting element located between rows of supports carries a trust. Servicing of a fish crib is performed using two cranes with carriages. The system claims an advantage of easier maintaining of the plant with possible arrangement of larger numbers of fish cribs in the sea and simplified servicing.
It has been known in the art to convert oil rigs to fish habitat by toppling the rigs after they are abandoned. This concept was reported for example in the Washington Post Sep. 4, 1993 in an article entitled "Oil Rigs Convert to Fish Condominiums". The September, 1993 Washington Post article discloses that very large offshore oil platforms (for example 300 plus feet long) create an artificial reef for marine life when the oil production platform is turned on its side and sunk in the gulf of Mexico.

Aquaculture apparatus for use adjacent an offshore fixed platform


The semiconductor integrated circuit device formed on one semiconductor substrate employs a plurality of first and second circuit blocks constituting functions of the same kind. The first and second circuit blocks, however, are implemented with respectively different types of circuits. The type of circuit employed in the respective first and second circuit blocks is necessarily consistent with the particular operation speed requirements thereof, such as, in connection with high-speed and low-speed circuit requirements for writing into the memory of a display system.

The present invention relates to a semiconductor integrated circuit device having a plurality of operating speeds and a system using the device and, more particularly, to techniques effective when used in a multi-port memory used in an image processing technology and an image processing system using the same.
Generally speaking, the integrated circuit device for the digital signal processing is systematized according to its operating speeds. In case one system is to be prepared, its whole system is constructed by organically combining a variety of in-system integrated circuits having an identical operating speed.
In a multi-port random access; memory (which will be shortly referred to as the "multi-port" RAM), for example, a plurality of word lines and a plurality of data lines are connected with each memory cell so as to give one memory cell a plurality of input/output terminals (or I/O ports). In order to give a static memory cell two I/O ports, for example, two word lines and two pairs of complementary data lines are connected with one memory cell. In order to accomplish the write-in and read-out operations of each I/O port, moreover, two series of decoders and two series of read/write circuits are provided in a memory unit. These two series of decoders and read/write circuits are constructed to have a substantially equal operating speed. In other words, these two series of circuits are composed of CMOS (Complementary Metal Oxide Semiconductor) circuits.
In a color palette LSI (Large-scale Semiconductor Integrated circuit device) having a dual-port memory assembled therein, on the other hand, there are provided two products, one being composed of a CMOS circuit only whereas the other being composed of an ECL (Emitter Coupled Logic) circuit only. These two color palette LSIs are separately used according to the operating speeds of a system for processing an image to be formed.

Semiconductor integrated circuit device including high-speed operating circuit and low-speed operating circuit, and system using the same


An assembly of a rim and a closed toroidal tire. The tire includes a tire casing and a ring, defining a tight chamber. The ring provides a mounting base on the rim and forms a sleeve designed to rest on said rim in mounting position. The ring includes a protuberance having a locking surface, intended to be engaged in a complementary groove arranged on the rim in order to oppose any relative movement between tire and rim axially in at least one direction. The ring has such a degree of flexibility that a pressure reduction of the chamber causes a displacement of said protuberance toward a larger radius. The tire can, for example, be fitted on the rim, and then the vacuum can be eliminated so that the protuberance will be engaged in the groove.

The present invention relates to tires. In particular, it concerns the mounting and demounting of a tire casing on and off a rim, and it also concerns, consequently, the mounting and demounting of tire casings on a vehicle, for example, for their replacement.
It is known that the development of wheels equipped with tires has led to a trend in design which, at present, consists of making the wheel easily demountable from the vehicle, the tire being removable from the wheel in an operation carried out at the shop with specialized machines. As is well known, the wheel is demountable from the hub of a vehicle usually by unscrewing a set of bolts. The wheels, the rims and the beads of a tire casing are covered by manufacturing standards which dictate the outer shapes and dimensions of those parts (see, for example, the ETRTO in Europe).
Most wheel and tire assemblies are made according to the principle just mentioned. This is the case with almost all equipment for passenger vehicles. It is also the case with most equipment for trucks, construction machinery, fanning or logging equipment, etc. As far as the largest dimensions are concerned, for example, to equip construction machinery or earth movers, the assemblies are built according to comparable principles, except that the rim is generally made in several parts assembled by a large number of bolts. This corresponds to a tire casing section having the general appearance of a horseshoe (xe2x80x9cxcexa9xe2x80x9d) open on the side of the axis of rotation of the tire, which proves simpler to manufacture than other types of sections (see, for example, the closed toroidal tire); the manufacturing facilities available have been developed and optimized for this type of tire. The open xe2x80x9cxcexa9xe2x80x9d shape is also appreciated because it makes it possible to inspect the inside of the casing and affords access to the inside of the casing in order to repair it, if necessary.
The present state of the art is the result of a technological evolution which, in the course of time, has been directed at offering tire and wheel assemblies which are as easy as possible to mount on and demount from the vehicle. Thus, the solution proposed for passenger vehicles makes possible the removal of the wheel and tire assembly from the hub simply enough to be within the ability of the ultimate user.
There have been very few technological developments in the course of the past decades concerning the principle of mounting a tire casing on the wheel and the principle of mounting the wheel on a vehicle. In some specific applications, such as wheel and tire assemblies for racing cars (like the Formula 1), in order to be able to mount and demount the equipment as quickly as possible, a center attachment wheel is used, making it possible to fasten the wheel to the hub of the vehicle very rapidly. But this type of fastening requires the use of very specific tightening and loosening wrenches, which are not available in most machine shops. The problem of wheel and tire equipment mounting and demounting time also arises for truck fleets or for construction equipment.
In the course of the specification, the expression xe2x80x9ctire casingxe2x80x9d is reserved for the object having two sidewalls attached to a crown part having a tread, the two sidewalls each ending radially inward in a bead. This is the commercial product as commonly manufactured nowadays. The part indeformable to working stresses, on which the tire casing is mounted, is called a xe2x80x9crimxe2x80x9d, the beads serving to position the tire on the seats of a rim. A xe2x80x9cwheelxe2x80x9d includes a rim and the means for mounting that rim on a hub, which is, for example, usually a wheel disk. As used herein, a xe2x80x9ctirexe2x80x9d is an assembly constituting a toroid delimiting a tight chamber that can be inflated to the normal working pressure provided for by the designer. A tire casing mounted on the rim is one of the possible ways of making a tire (in the meaning given to the word xe2x80x9ctirexe2x80x9d hereabove).
However it is made, the mounting of a tire casing on a rim consists of positioning the beads on the rim seats and against the rim flanges. Each rim seat requires centering (radially) and generally presents a slight conicity making possible a degree of tightening of the casing, when the bead is axially displaced toward and up to the flange, which requires of it an axial positioning relative to the fastening surface of the wheel on the hub of the vehicle. In other words, the rim seats can be considered positioning the beads relative to the axis of rotation of the rim, while the rim flanges position the bead relative to a reference perpendicular to the axis of rotation of the rim. In addition to the function of imposing a geometrically precise position for the bead of the tire casing, the rim seat and the rim flange also have the function of ensuring tightness between the rim and the tire casing, and have the function of making it possible, through sufficient tightening of the tire on its rim, to transmit a torque between the rim and the tire casing.
The object of the present invention is to simplify radically the mounting and demounting of a tire on and off the vehicle it equips. According to one aspect of the present invention, the mounting and demounting of a tire casing or of a tire on and off the rim supporting it do not necessitate a specialized mounting machine, like those making it possible to have the flange of the rim crossed by the beads of the tire casing, nor the tightening or loosening of a large number of bolts. The invention proposes a solution which makes it possible to fit a tire on a support that it will be convenient to call xe2x80x9crimxe2x80x9d (because it is a support not deformable on working stresses) in a very simple manner: a simple relative transverse displacement between tire and rim suffices, the tire and rim remaining with merged axes during the relative translation movement.
The invention proposes a toroidal tire including, as seen in mounted position on a suitable rim:
a mounting base on the rim, said base forming a sleeve extending crosswise and being capable of forming a closed toroid defining a tight chamber, said base constituting the radially innermost wall of said toroid;
said base being intended to be mounted on the rim; securing means for axially opposing any relative movement of the tire on the rim at least in one of the two directions, said securing means being:
arranged on the radially inner face of the base;
designed to cooperate with a complementary bearing arranged on the rim in order to oppose any relative movement between tire and rim axially in the said direction at least;
arranged in a part of the base which presents a degree of flexibility between a relaxed natural position and a position radially stressed outward, in which those securing means are free of any engagement with the said complementary element, said part of the base and the securing means being so shaped and constituted that, when said chamber is at the same pressure as the atmospheric pressure prevailing outside the chamber, the securing means are engaged with the complementary element, so that the tire will be automatically secured in at least said one direction on the rim, release of the securing means requiring subjecting the latter to the action of outside means serving to make said securing means take said position stressed radially outward.
Depending on the applications, the xe2x80x9csecuring meansxe2x80x9d can take many different forms, some of which gives them the shape of a localized mechanical locking element, and others a more spread out shape. One designates here means which contribute to oppose any relative movement of the tire on the rim and which contribute to the security of the immobilization of the tire on its rim. Let us note also that the so-called xe2x80x9crelaxed naturalxe2x80x9d position of the securing means can be different from the one they have when they are engaged with the complementary bearing of the rim, the latter (engaged position) generally being an intermediate position between the relaxed natural position and the position stressed radially outward, in which those securing means are free of any engagement with the said complementary element.
According to one particular embodiment, said securing means include a locking element made in the form of a protuberance or groove, arranged on the radially inner face of the base axially at an intermediate position, said locking element having a predetermined height (H) measured parallel to a radius from the inner face of the base, and the said complementary bearing arranged on the rim being adapted to said locking element.
It is known that a tire generally comprises a crown part comprising a tread. The concept of the invention having been defined above, let us point out how said degree of flexibility can be adjusted (through the choice of materials and design) for an excellent operation of the invention. It is advisable that, when the tire is in a closed toroid configuration defining a tight chamber, a pressure reduction of the chamber produces the desired displacement of said locking element toward the larger radius before producing a deformation of the crown, the extent of which opposes said displacement of the base to the larger radius. It is therefore advisable, through a judicious sizing of the locking element and of the base supporting it, as well as through a judicious sizing of the crown part (the rigidity of which must be sufficient), for the increase in diameter of the locking element not to impose overly great stresses or, in any case, for the crown part to stand up well enough not to collapse. Preferably, it is desirable for what is stated above to remain true regardless of the degree of wear of the tire, so that demounting can take place under the same conditions as mounting. However, as will be seen below, some applications of the invention do not resort to a pressure reduction of the inner chamber of the tire. Consequently, this aspect is not universal.
From another aspect, the invention proposes a combined toroid tire and rim assembly, said rim coming in a single piece and said toroid tire including, seen in mounting position on a suitable rim:
two sidewalls;
a mounting base on the rim, said base forming a sleeve extending crosswise from each sidewall in the direction of the other sidewall, the radially inner ends of the sidewalls being extended by said base:
a crown part comprising the tread and joined to the radially upper end of the sidewalls, in which said base:
is capable of forming a closed toroid defining a tight chamber, complementing the sidewalls and the crown part, even when the tire is not mounted on the rim;
includes a concurrent locking part on the rim, situated axially between the sidewalls, said concurrent locking part presenting, in stress-free state, a minimum perimeter (Pm), the rim having a support area in the radial projection of said base, when the tire is considered in mounting position on the rim, said support area presenting a minimal (Pjm) opposite the portion of the concurrent locking part and, axially on at least one side of the part presenting the minimum perimeter (Pjm), an area presenting a maximum perimeter (PjM) greater than (Pjm) and capable of receiving the toroidal tire on the rim, the total rim situated on said side presenting a perimeter no greater than (PjM) in any axial position, said minimum perimeter (Pm) of the concurrent locking part being less than the maximum rim perimeter (PjM), said concurrent locking part being elastically extensible, so that, when the tire is in place on the rim, the concurrent locking part cooperates with the rim in opposing any relative movement of the tire in relation to the rim at least axially toward said side.
Several embodiments of the invention are described below, which can be classified in three families:
The first family uses tire casings of appearance identical or very close to the shape of the tire casings in current use on the priority date of this invention. They are tire casings which are hooked on the rim against a flange situated axially outside the rim. The ETRTO standards in force on the priority date of this invention should be consulted, for example, to get more precise information on the standardized shape of the corresponding tire casing and rim beads.
A second family uses a tire casing having the general appearance of a toroid split in its radially inner wall.
Finally, a third family uses the principle of a tubular tire: it involves a toroid-shaped tire containing a tight closed cavity obtained on molding of the tire.
The second and third families propose developing a tire casing or closed tubular tire, not currently available today. As for the first family, it enables the today existing tire casings to be used, adding to them a ring specifically developed to form, by combination with a standard tire casing, a tire having the mounting and demounting properties proposed in the present invention.
The invention therefore also extends to a ring designed to be mounted under the beads of a tire casing having a crown, two sidewalls each ending in a bead, in order to form, after mounting of the beads on the ring, a tire designed to be mounted on an adapted rim, said ring including two seats, each receiving a bead, and including securing means for axially opposing any relative movement of the tire on the rim in one of the two directions at least, said securing means being:
arranged on the radially inner face of the ring;
designed to cooperate with a complementary bearing arranged on the rim in order to oppose any relative movement between tire and rim axially in the said direction at least;
arranged in a part of the ring which presents a degree of flexibility between a relaxed natural position and a position radially stressed outward, in which those securing means are free of any engagement with the said complementary element, said part of the base and the securing means being so shaped and constituted that:
when said chamber is at the same pressure as the atmospheric pressure prevailing outside the chamber, the securing means are engaged with the complementary element, so that the tire will be automatically secured in said one direction at least on the rim,
the release of the securing means requiring subjecting the latter to the action of outside means serving to make said securing means take said position stressed radially outward.
As already explained above, the securing means can be a locking element taking the shape of a protuberance or groove, arranged on the radially inner face of the ring at a position axially separated from the seats, said locking element having a predetermined height (H) measured parallel to a radius from the inner face of the ring, the said complementary bearing arranged on the rim being adapted to said locking element. The remarks made above regarding the degree of flexibility are also applicable.
Through the choice of materials, design and sizing of the ring, it can very easily be given sufficient flexibility in the median part between the seats. There again and by comparison with the pliancy of the ring, the rigidity of the crown part must be sufficient for the reduction in pressure of the tire to produce an increase in diameter of the median part of the ring without the crown part collapsing.
In all the families, it is to be noted that the rim used is not tight or, more exactly, that it is the tire itself which has to be tight. Tightness is ensured between tire casing and ring in the first family and at the closure in the case of the second family (split toroidal tire). In other words, the air coming from the air chamber and that might have reached between the tire and the rim must be able to escape, so that there is no pressure build up between rim and mounting base. Such looseness of the rim can be obtained, for example, because the constituent material is porous, or because there are small vent holes judicially arranged, or because there are grooves correctly placed and oriented to the radially outer surface of the rim, or also because there are grooves correctly arranged and oriented to the radially inner surface of the mounting base. Other expedients can also be used, such as textile drains or a draining surface coating. Securing efficiency thereby does not change in time.
From another aspect, the invention proposes reducing the pressure of the inner cavity of a tire in order to increase in diameter or facilitate the increase in diameter of a portion of the mounting base, which makes it possible to fit the tire easily on the rim, the final securing of the tire on the rim being carried out by eliminating the vacuum.
This mounting by simple relative translation is done without prejudice to obtaining a securing in a strictly determined axial position. The invention therefore makes it possible to devise and carry out a secure fastening of the tire on its rim, while greatly simplifying mounting, compared to the known solutions which resort to a rim having a center mounting space, the minimum depth of which is dictated by the height of the rim flanges, as well as to a rim in several pieces, or to a previous insertion of the rim inside the beads with relative rotation of the planes of the rim and tire casing. For mounting of the tire on the rim as well as for demounting, the invention provides for reducing the pressure of the inner chamber of the tire during mounting and demounting. Outside of the mounting and demounting operation, the invention proposes a solution which, when the tire is at atmospheric pressures, makes sure of a retention of the tire on the rim that is as safe and positive as with the known solutions of the state of the art. In fact, at ambient atmospheric pressure, without express stresses (a vacuum in relation to ambient atmospheric pressure does not exist naturally), the tire cannot be demounted accidentally, while, in the case of passenger vehicle tire casings and their hollow-base rims, as ETRTO standardized on the priority date of the present application, in case of total deflation, it is not impossible that the bead or beads might be spontaneously engaged in the mounting groove and then pass over the rim flange (a phenomenon known as rolling off the rim).
The invention thus extends to a method of mounting on a rim of a closed toroidal tire forming a tight chamber, said tire including:
a rim mounting base, said base forming a sleeve intended to rest on said rim in mounting position;
securing means for axially opposing any relative movement of the tire on the rim in one of the two directions at least, said securing means being:
arranged on the radially inner face of the base;
designed to cooperate with a complementary bearing arranged on the rim in order to oppose any relative movement between tire and rim axially in the said direction at least;
arranged in a part of the ring which presents a degree of flexibility between a secured position and a radially outermost unsecured position;
said method including the following steps:
when the tire is in a closed toroidal configuration defining a tight chamber, reducing the pressure of the chamber until producing a sufficient displacement of the securing means toward the larger radius;
fitting or completing the fitting of said tire on said rim until it takes its final axial position relative to the rim;
eliminating the vacuum so that the securing means are displaced toward the smaller radius.
The invention also concerns a method of demounting off the rim of a closed toroidal tire forming a tight chamber, said tire including:
a rim mounting base, said base forming a sleeve intended to rest on said rim in mounting position;
securing means for axially opposing any relative movement of the tire on the rim in one of the two directions at least, said securing means being:
arranged on the radially inner face of the base;
designed to cooperate with a complementary bearing arranged on the rim in order to oppose any relative movement between tire and rim axially in the said direction at least,
arranged in a part of the ring which presents a degree of flexibility between a secured position and a radially outermost unsecured position;
said method including the following steps:
creating a greater pressure acting on the tire between rim and tire than the pressure prevailing in the tight chamber, in order to produce a sufficient displacement of the securing means toward the larger radius;
removing said tire from said rim by sliding it axially.
In an advantageous use of the demounting method, in order to create a greater pressure between rim and tire than in the tight chamber, the pressure in said chamber is reduced, while the tire floats outside at atmospheric pressure. As a variant, in order to obtain a difference in pressure on both sides of the mounting base, instead of lowering the pressure prevailing in the tire chamber under atmospheric pressure, a fluid can also be injected under pressure between the rim and the mounting base, ideally in a place close to the securing means, which can be done, for example, through a vent hole provided on the rim, as explained above. Said securing means can also be possibly mechanically stressed, that is, pushed radially, in addition to or in place of a reduction of the pressure prevailing in the tire chamber. The methods of mounting and demounting described above propose a step in the course of which the toroidal tire slides by simple axial movement relative to the rim, without requiring a bead of a tire casing to be engaged in a mounting groove; these methods prove interesting and have broader applications than in connection with a tire according to the invention; for example, in case the tire should be well secured axially in relation to the rim, it is still necessary to perfect securing by creating a hooping or increasing the hooping of the base on the rim through inflation of the tire chamber; the fact of stressing said securing means radially toward the wider radii contributes to the relative axial movement between base and rim.
The invention will be better understood by the description to follow of several non-imitative examples, and by reference to the attached drawings:

Simplification of mounting and demounting of a tire on and off its rim

Compagnie Gxc3xa9nxc3xa9rale des Etablissments Michelin and Cie


A method of fabricating an optical fiber having an asymmetric refractive index profile that varies periodically along the length of the fiber is described. The prescribed variations are obtained by means of a fabrication process that includes periodically varying the source of at least one of the fiber materials in a direction transverse to the fiber-drawing direction. This transverse periodicity is translated into the desired longitudinal periodicity along the fiber by the fiber-drawing process.

In U.S. Pat. No. 3,687,514 it is shown that the mode dispersion in a multimode waveguide can be reduced by deliberately enhancing the mode conversion processes in the waveguide. This is accomplished by introducing "imperfections" in the waveguide, such as changes in the cross-sectional dimensions of the guide and/or changes in the orientation of the guide axis. Arrangements for fabricating optical fibers having such variations are described in U.S. Pat. Nos. 4,038,062; 3,666,348; 3,912,478; and the previously cited U.S. Pat. No. 3,687,514. However, the periodicity of the resulting spatial variations produced by all of these techniques is much greater than one would like. As a result, the net coupling length for the fiber is relatively large and the reduction in the dispersion is correspondingly small.
In an alternative technique, described in U.S. Pat. No. 3,909,110, refractive index variations are built into the preform from which the fiber is to be pulled. This, however, requires considerable care in the preparation of the preform and, hence, tends to be a relatively expensive method.

Method for fabricating optical fibers with enhanced mode coupling

Bell Telephone Laboratories, Incorporated


Examples of an apparatus and method are disclosed herein. In an example of the method, the performance of an ejection device that dispenses a composition is measured, information representative of the measured performance of the ejection device is generated, and the information representative of the measured performance of the ejection device is recorded so that the information is visually perceptible.

Some devices or processes may utilize replaceable components or sub-assemblies. Some of these replaceable components or sub-assemblies may be covered by warranty or other type of guarantee in the event of premature failure or inadvertent damage. Designers, manufacturers, distributors and/or suppliers of these replaceable components or sub-assemblies may, therefore, be interested in information concerning sage of such components or sub-assemblies as it pertains to any warranty or other guarantee they provide.

Visual performance information of an ejection device

HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P.


A gas turbine having a compressor, a turbine unit, at least one combustion chamber and a secondary air system, which secondary air system has at least one cooling line having a compressor-side inlet for removing cooling air from the compressor and a turbine-side outlet for leading the cooling air onward into the turbine unit, wherein the cooling air line at the compressor-side inlet is connected fluidically to a housing opening of the gas turbine which adjoins a cavity in the gas turbine and which, during operation, guides compressor air, and wherein the housing opening is formed as a manhole.

During partial load operation of a gas turbine, the combustion temperature in the combustion chamber typically drops. This also causes a drop in the primary zone temperature (TPZ), i.e. also the combustion chamber temperature, which is relevant for CO emissions. If the temperature falls below a predefined minimum value of the TPZ (e.g. TPZ<1400, ° C. for 10 , ppmv CO emissions), the production of CO emissions increases, and as a result the limit of the useful partial load range of the gas turbine—which conforms to CO emissions limits—is reached. Where legal limits on CO emissions exist, this circumstance can force the operator of the gas turbine to switch off the gas turbine since it is sometimes no longer possible to further reduce the power of the gas turbine without simultaneously exceeding the relevant CO emissions limit.
One technical solution, known to the applicant from the internal prior art, for reducing CO emissions in partial load operation relates to diverting and bypassing cooling air so as to reduce the quantity of compressor outlet air which enters the combustion chamber. Thus, combustion in the combustion chamber can take place with a relatively large quantity of fuel and at a relatively high TPZ, thus reducing CO emissions. The pipes required for bypassing and diverting cooling air, or the pipe ends generally designed as outflow and inflow line stubs, are in this case securely attached to the gas turbine casing. When considering these components and their arrangements, it is particularly important to ensure that both the mechanical and the operational stability of the gas turbine is not greatly influenced.
Furthermore, also with regard to attaching the pipes or the pipe ends, it is important to ensure that the accessibility of the gas turbine for maintenance purposes is not markedly restricted. In that regard, attaching such pipes is subject to limits relating to stability, operation and maintenance.

Cooling air line for removing cooling air from a manhole of a gas turbine


A high voltage electrical swivel includes a first part and a second part, which are mobile relative to each other and form a closed internal chamber, each of the two parts including at least one electrical connector; and at least one electrical track electrically linked to a connector of one of the two parts and at least one brush assembly electrically linked to a connector of the other of the two parts, the at least one brush assembly cooperating with the at least one electrical track to establish an electrical contact, the at least one electrical track and the at least one brush assembly being housed in the closed internal chamber. The closed internal chamber is filled with a dielectric insulating gas having a dielectric strength greater than that of the air surrounding the electrical swivel.

An electrical swivel, also termed electrical collector or slip ring joint, is an electro-mechanical device used to transfer electricity between two parts that are mobile relative to each other (one part being considered to be fixed or "geostationary" and the other rotary).
The general principle of such a device relies on the implementation of circular conducting tracks cooperating with mobile brush assemblies in order to establish electrical connections, typically with several electrical phases.
Electrical swivels are commonly used in robotics, in particular on production lines.
They are also used in more specific applications, for example at sea to establish an electrical connection between an underwater device and a ship.
FIG. 1 illustrates such an example of use. As illustrated, an electrical swivel 100 is used here on board a ship 105 to establish an electrical junction between a cable 110 connected to an underwater electrical system (not shown) and a cable 115 connected to an electrical system of the ship 105.
In such an application, referred to as "offshore", the electrical swivel is generally a high-voltage electrical swivel used for voltages greater than 1 500 V for direct current or 1 000 V for alternating current, enabling the transfer of high electrical power between a fixed structure linked to the sea bed and a mobile part such as an FPSO (initialism of Floating Production, Storage and Offloading vessel).
Electrical swivels used in such applications must meet predetermined quality requirements to provide a certain level of security, in particular in an explosive atmosphere.
For such purposes, the electrical swivels implemented generally comprise an internal chamber within which are placed conducting tracks and associated brush assemblies. The internal chamber is filled with a dielectric fluid, typically oil.
The dielectric fluid enables each conducting track to be insulated in order to prevent electrical arcs forming with neighboring conducting parts (generally metal parts) and to reduce the distance between the conducting tracks. More particularly, the minimum distance between the conducting tracks is linked to the dielectric strength of the medium in which they are located, it being possible for the dielectric strength of oil to be ten times higher than that of air (under standard pressure, for example a normal pressure of one atmosphere). It is to be recalled here that the dielectric strength of a material is expressed in kV/mm (kilovolts per millimeter) and characterizes the maximum electric field that may be applied between two different electrodes before an electric arc is produced and therefore breakdown.
However, although the dielectric strength of oil is much greater than that of the air and enables the distances between the conducting tracks to be significantly reduced, these distances are also linked to the electrical voltage at the terminals of the electrical swivel. Thus, for high voltages, the electrical swivels are necessarily of large size and require a high quantity of oil. This results in devices that are heavy and bulky.
The invention enables at least one of the problems set forth above to be solved.


An apparatus for exercising pelvic floor muscles is provided that allows the user to adjust the force against which she must act so as to maximize the effect of the exercise. The apparatus of the present invention comprises a shaft having a proximal end and a distal end. Attached to said proximal end of said shaft is an intra-vaginal portion designed for the user to contract her pelvic floor muscles against and attached to said distal end of said shaft is a grasping means by which the user may apply variable force so as to maximize the force against which the user""s contracted pelvic floor muscles must resist.

The present invention relates to an apparatus for exercising pelvic floor muscles. More particularly, the present invention relates to an apparatus for exercising pelvic floor muscles that allows for constant resistance and feedback to the user.
Exercises for perineal muscles, also known as pelvic floor muscles, are often recommended as therapy to aid correction of a number of problems including but not limited to urinary incontinence or physical stress incontinence. Other common problems resulting from lack of proper or adequate toning of the pelvic floor muscles include fallen bladder, fallen rectum, uterine prolapse, difficulties with voiding, cystitis, decreases in sexual responsiveness and chronic discomfort. Absent a routine exercise program lack of muscle tone can result in muscle atrophy thereby resulting in an exacerbation of the above conditions and could require a variety of surgical corrections.
It is well documented that a regular exercise program involving this muscle group can result in improved muscle tone resulting in a concomitant improvement in voluntary muscle control, increased strength and re-enervation of previously injured muscles. Such an exercise program can enhance sexual responsiveness and pleasure of both partners during intercourse. Moreover, it is known that improved muscle tone resulting from such an exercise routine is desirable in preparation for childbirth. Use of the device postpartum shortens healing time and hastens the return of tone of the pelvic region. The same is true post-hysterectomy.
Numerous intra-vaginal devices have been described, some ranging from the complex to the simple. These simple devices generally involve the use of weights which are attached to that portion of the device that is extra-vaginal. Such weights apply constant pressure and rely on gravity as the operating means. The user of these devices contracts her pelvic floor muscles around the intra-vaginal portion of the device and thereby provides resistance to the force applied by the weights. It is that resistance that enhances muscle tone.
These devices, however, have several shortcomings. To begin with, use of weights, of necessity, mandates that the amount of force against which the user can act may be increased or decreased in discrete weight units. That is to say, continuously varying the force in order to maximize the effects of the exercise is not possible with discrete weights.
Another shortcoming of the devices of the present invention is that in certain circumstances, such as partial paralysis, the user is not capable or does not desire to use the device in a manner which allows for the application of force due to gravity. That is to say, in the devices relying on gravity as the force inducer the device must be generally aligned so that the extra-vaginal portion of the device can be aligned in a generally perpendicular direction so that gravity may take effect. Such devices, therefore, do not allow for use in a prone position because in a prone position the device is not aligned such that gravity may provide direct force.
It would, therefore, be advantageous to have a simple, pelvic floor muscles exerciser that does not rely on gravity and allows for a constantly varying force to be resisted.
The present invention relates to an apparatus for exercising pelvic floor muscles with oppositional force. In particular, one that provides constantly adjustable and variable force against which the user controls both the contractions of the pelvic muscles and the pull or resistance of the apparatus, thereby providing optimal exercising conditions.
In one embodiment of the present invention, the apparatus for exercising pelvic floor muscles comprises an exerciser having an intra-vaginal section and an extra-vaginal section, the sections being connected by a shaft. The intra-vaginal section is generally smooth and oblong shaped and is made typically of an inert material resistant to bacterial and fungal growth such as a suitable plastic, thermoplastic, latex or like material. The shaft is rigid or semi-rigid, resilient and similarly made of an inert material resistant to bacterial and fungal growth. The extra-vaginal portion is ergonomically shaped so that the user may grasp it firmly The device is operated by insertion of the intra-vaginal portion into the vagina of the user, contraction of the pelvic floor muscles by the user around such intra-vaginal portion and application of force by the user against such muscles along an axis which upon muscle failure would result in extraction of the device from the user""s vagina.


With an aim of minimizing excitation losses in electric machines having electrically excited and displaceable secondary parts, bi-directional inductive transmission of energy is carried out by a rotating inductive transmission device. An associated electronic system for the bi-directional transmission of power and/or energy, is provided. Advantageously, super-conductive inductance is present wherein the flow is introduced. It is possible to excite by supplying energy to the stator and to also de-excite by removing energy without converting the power into heat on the rotor by applying a bipolar tension.

Described below is an excitation device for an electric machine. In particular, the electric machine is a synchronous machine, which preferably, but not exclusively, uses a superconducting inductance as the field winding.
In electric machines with an electrically excited and moved secondary part (rotor), such as in particular in the case of synchronous machines (SM), the excitation losses can advantageously be reduced to a minimum by implementing the exciter winding as a high-temperature superconducting (HTS) winding. For this purpose, however, the cooling of the superconductor to a temperature range of below 80K, i.e. at least the temperature of liquid nitrogen, is necessary.
In the case of a design with superconductors, any input of heat via mechanical contacts should be avoided as far as possible. Mechanical contacts, such as sliprings or the like, are involved as a result of the maintenance required and moreover are susceptible to wear. For this reason, the excitation power, the monitoring and regulation information is advantageously transmitted in contactless fashion, i.e. inductively, to the rotor. During operation of the machine, it is necessary to convert the de-excitation energy into heat when the field windings in the machine are demagnetized.
Known excitation devices for a superconducting winding typically include a contactless energy transmission path, a contactless control or regulating signal transmission path to a stationary control and regulating unit, and an actuator for impressing a voltage and a freewheeling circuit. In this case, the transformer in particular functions inductively.
EP 1 247 324 B1 proposes a unidirectional inductive energy transmission, a "rotating transformer" including two pot-type cores with ring windings and axial flux guidance being provided as inductive operating means. In this case, the pot-type cores can move toward one another about the common axis.
Inductively functioning operating means are described in detail in the dissertation: Albert Esser: "Berührungslose, kombinierte Energie- und Informationsübertragung für bewegliche Systeme" [Contactless, combined energy and information transmission for mobile systems] ISBN 3-86073-046-0; ISEA, RWTH Aachen 1992. The statements in the dissertation are aimed at contactless bidirectional energy and data transmission in robot joints.
DE 41 33 001 A1 has furthermore disclosed "photoelectric transmission" for the transmission of both energy and data. While the energy transmission has a deficient power density, data can be transmitted in a manner which is very insensitive to faults and free of potential. Such systems are commercially available. Such unidirectional energy transmission for exciting a superconducting winding needs a passive resistor on the cooled rotor for de-excitation, which resistor converts the excitation energy into heat, which then needs to be dissipated. Both the input of heat and the passively and exponentially decaying excitation are in this case undesirable.
Against the background of the related art, an improved excitation device for a winding which can be used in electric machines.

Excitation device for an electric machine


Disclosed herein is a viscoelastic resin composition for vibration-damping material which comprises (A) at least one amorphous polyester resin of low specific gravity in which more than 40 mol % of the dibasic acid moiety is of aromatic type, (B) at least one amorphous polyester resin of high specific gravity in which more than 80 mol % of the dibasic acid moiety is of aromatic type, and (C) at least one hardener selected from the group consisting of polyisocyanate compounds, epoxy group-containing compounds, and acid anhydrides, said consitutents (A) and (B) being in the ratio of from 90:10 to 30:70 by weight and differing from each other in specific gravity (at 30.degree. C.) by 0.06 to 0.15 and also in molecular weight by more than 10000, with that of either of them being higher than 5000. This resin composition gives a vibration-damping material which exhibits improved vibration-damping properties, adhesive strength, formability, and heat resistance after forming.

1. Field of the Invention
The present invention relates to a viscoelastic resin composition for vibration damping material and more particularly to a viscoelastic resin composition for vibration-damping material to form an intermediate layer in the laminate structural member of machines, buildings, and vehicles.
2. Description of the Prior Art
In these days of well-developed traffic facilities and disordered urban environments where dwelling houses are close to factories, noise and vibration constitute a social problem as public nuisance. Noise and vibration also aggravate the working environment. Attempts are being made to reduce noise and vibration by providing the metal material as a source of noise and vibration with the vibration-damping function to absorb vibration energy and convert it into thermal energy, thereby damping the vibration velocity or vibration amplitude and reducing the acoustic radiation.
To improve the vibration-damping function, there has been proposed a composite vibration-damping material of laminate structure which is composed of metal layers and a viscoelastic intermediate layer interposed between them. It is now in use as a structural member for automotive engine cover and oil pan, hopper chute, conveyor stopper, household electric appliance, metal working machine, and precision machine, which are required to generate as little vibration as possible.
In general, the composite vibration-damping material mentioned above depends for its performance on the viscoelastic intermediate layer. The vibration-damping performance is expressed in terms of loss factor (which indicates a degree of conversion of external vibration energy into thermal energy by internal friction, or an amount of mechanical hysteresis loss caused by vibration). The loss factor has a peak value at a certain temperature, and the vibration-damping material can be used most effectively in the neighborhood of that temperature.
According to the known prior art technology, the conventional composite vibration-damping material has a viscoelastic intermediate layer which is made of polyester alone (*1), polyester incorporated with a plasticizer (*2), polyester incorporated with an organic peroxide (*3, 4), a plurality of polyesters in combination (*5, *6), polyurethane foam alone (*7), polyamide alone (*8), ethylene-vinyl acetate copolymer (*9), polyvinyl butyral or polyvinyl butyral-polyvinyl acetate composition incorporated with a plasticizer and tackifier (*10), copolymer of isocyanate prepolymer and vinyl monomer (*11), or a specific copolymer (*12, *13, *14). FNT *1Japanese Patent Kokai No. 143880/1975 FNT *2 Japanese Patent Kokai No. 93770/1976 FNT *3 Japanese Patent Kokai No. 41080/1976 FNT *4 Japanese Patent Kokai No. 83640/1976 FNT *5 Japanese Patent Kokai No. 295949/1987 FNT *6 Japanese Patent Kokai No. 202446/1988 FNT *7 Japanese Patent Kokai No. 91981/1976 FNT *8 Japanese Patent Kokai No. 159160/1981 FNT *9 Japanese Patent Kokai No. 34949/1982 FNT *10 Japanese Patent Kokai No. 27975/1980 FNT *11 Japanese Patent Publication No. 27975/1980 FNT *12 Japanese Patent Kokai No. 258262/1985 FNT *13 Japanese Patent Publication No. 12451/1964 FNT *14 Japanese Patent Publication No. 34703/1970
The composite vibration-damping material is required to have a high loss factor and a high adhesive strength between the viscoelastic intermediate layer and the metal layer. However, these requirements have not been fully satisfied. For example, vibration-damping performance and adhesive strength do not consist together at room temperature in the case where the viscoelastic intermediate layer is made of polyester resin (as in Japanese Patent Kokai Nos. 143880/1975, 93770/1976, 41080/1976, and 83640/1976), or even in the case where the viscoelastic intermediate layer is made of a plurality of polyesters in combination (which differ in glass transition point) so that it produces its vibration-damping effect over a broad range of temperature (as in Japanese Patent Kokai Nos. 295949/1987 and 202446/1988).
Moreover, the composite vibration-damping material having a viscoelastic intermediate layer should be capable of fabrication such as pressing and bending. However, conventional ones do not meet this requirement; they are liable to wrinkling and cracking during fabrication and also to peeling between the viscoelastic intermediate layer and the metal layer during heat treatment (such as baking finish) which follows fabrication.

Viscoelastic resin composition for vibration-damping material


Novel methods for preparing masking tapes by coating a thin layer of a polyolefinic material onto a lightweight nonwoven cloth and then applying a layer of adhesive, preferably a hot melt adhesive onto the opposed surface of the nonwoven cloth; and novel masking tapes prepared thereby.. In the preferred embodiments, the polyolefinic layer consists essentially of a thin stratum of a high density polyethylene and a thin layer of low density polyethylene.

The present invention relates to finger-tearable adhesive tapes of the class known in the art of masking tapes.
While the patent literature is replete with references to masking tapes, those commercially available today employ a crepe paper base or backing for the pressure-sensitive adhesive layer. This paper base is first saturated with a latex binder and then dried. A release coating may then typically be applied to one side of this paper base and a pressure-sensitive adhesive to the other.
The saturation step with the latex binder to improve cohesive strength of the paper and the application of the release coating to provide ease of unwind of the tape both require energy for solvent removal.
A primary object of this invention is to provide a more cost-effective method for manufacturing masking tapes.
Another object is to provide masking tapes having improved elongation and conformability.
Other objects of the invention will be apparent from the following detailed description of the invention.


An aeration device configured to be fitted to a membrane filtration module having membranes mounted therein. The aeration device comprises a sleeve configured to at least partially surround the membrane filtration module. The sleeve has one end adapted to engage with the membrane filtration module and another end adapted to engage with a filtrate collection conduit or manifold.

Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field.
Membrane filtration systems typically can be operated in a single or double-ended manner. That is, filtrate can be withdrawn from one or both ends of the membranes, particularly when the membranes are in the form of tubes or fibres. Double-ended systems are typically more efficient in that more permeate can be withdrawn from the membranes within a set period due to reduced pressure drop along the length of the membrane.
Similarly, the efficiency of the membrane filtration systems is typically dependent on the surface area of the membrane exposed to liquid to be filtered. In the case of filtration systems using bundles of membranes tubes or fibres, the surface area of the system may be increased by a number of methods including increasing the packing density of the tubes or fibres and/or by increasing the length of the tubes or fibres extending between their end supports.
The success of a membrane filtration process largely depends on employing an effective and efficient membrane cleaning method. Porous membrane filtration systems require regular backwashing of the membranes to maintain filtration efficiency and flux while reducing transmembrane pressure (TMP) which rises as the membrane pores become clogged with impurities. Typically, during the backwash cycle the impurities are forced out of the membrane pores and/or scoured from the membrane surfaces into the feed tank or cell by one or more of pressurised gas, gas bubbles, liquid, or a mixture thereof. The liquid containing impurities and deposits from the membranes is then drained or flushed from the tank.
Minimising the footprint of filtration systems is desirable in terms of space eventually occupied by the filtration plant. Compact systems have lower cost, less waste volume, lesser impact on the environment and are more acceptable to the market.


A high pass filter includes: an input-impedance-matching taper transition metal layer having an IMT input end and an IMT output end, the IMT input end having an IMT input end width, the IMT output end having an IMT output end width that is wider than the IMT input end width; a substrate integrated waveguide having a SIW input end and a SIW output end; and an output-impedance-matching taper transition metal layer having an OMT input end and an OMT output end, the OMT input end having an OMT input end width, the OMT output end having an OMT output end width that is wider than the OMT input end width. The substrate integrated waveguide is arranged such that the IMT output end is electrically connected to the SIW input end and such that the OMT input end is electrically connected to the SIW output end.

Embodiments of the disclosure relate to high pass filters for microwave systems.
For applications where a wideband radio is constantly sensing its environment, strong interferers that lie close to in-band can desensitize the receiver. This is especially true for radio receivers that operate close to high power radar bands. For this reason, microwave filters are often employed to attenuate undesirable signals while preserving signals of interest. For example, one type of receiver is designed to operate >18 GHz. However there are known high power radars below this frequency that can affect the receiver, and for this reason, a microwave high pass filter is necessary.
Typically, in order to achieve high levels of rejection, high order filters are required. Typically, filters are synthesized using lumped element equivalent models from capacitors, inductors, and resistors. The problem with realizing filters at microwave frequencies is that parasitic effects can dominate responses. For example, if a filter were designed with a spiral inductor at microwave frequencies, the inductor may not behave as an ideal inductor, and will have distributed characteristics. For this reason, synthesizing high order microwave filters using lumped elements is difficult.
A high pass filter is unique in that its behavior is much like a waveguide. A rectangular waveguide has a cut-off frequency below which it will not pass signal. A waveguide is compact in size, simple to implement as it is a transmission line modality, and has the lowest loss of all transmission line modalities. Realizing a waveguide on a printed circuit board is the challenge. A rectangular waveguide is a metal structure with set dimension based on the operating frequency.
A prior art high pass filter uses a microstrip with a short-circuited edge. The filter will be described in further detail with reference to FIG. 1. FIG. 1 illustrates a prior art high pass microwave line 100 with a shorted edge.
As shown in the figure, high pass microwave line 100 includes a dielectric substrate 102, an electric wall 104 and a conducting line 106. Conducting line 106 includes a transmission direction portion 108 and a folding portion 110. Electric wall 104 is disposed on a side wall 105 of dielectric substrate 102 so as to extend in a normal direction over dielectric substrate 102. Electric wall 104 provides a short to the bottom of dielectric substrate 102 for conducting line 106.
Conducting line 106 is disposed on dielectric substrate 102 such that transmission direction portion 108 is disposed to provide a direction for transmission of a radio frequency (RF) signal in a direction parallel to electric wall 104 as indicated by dotted arrow 112. Conducting line 106 is additionally disposed on dielectric substrate 102 such that a portion of folding portion 110 extends to electric wall 104, folds down over the thickness of dielectric substrate 102 and further extends to the underside of dielectric substrate 102 as indicated by dotted portion 114.
The width, w, of transmission direction portion 108 is the transmission length of high pass microwave line 100. A distance, x, is from electric wall 104 to the middle of transmission direction portion 108. The length, l, of folding portion 110 in combination with x tune the frequency of high pass microwave line 100. So changes to either l or x will change the cut off frequency of high pass microwave line 100.
FIG. 2 illustrates a graph 200 of the band-pass characteristics of the prior art high pass microwave line 100 with a shorted edge of FIG. 1. As shown in FIG. 2, graph 200 has a y-axis 202, an x-axis 204 and a plurality of sample that follow function 206. Y-axis 202 is in decibels and corresponds to the power transfer of high pass microwave line 100. X-axis 204 is in GHz and corresponds to the frequency of the transmitted signal.
As can be seen in the figure, below the cut-off frequency of 8 GHz, the insertion loss is large, and above the cut-off frequency, the insertion loss is small. The insertion loss in the pass band is primarily due to radiation loss of the microstrip transmission line modality. Nevertheless, the roll-off of high pass microwave line 100, as noted by function 206 at about 8 GHz indicates that high pass microwave line 100 is an effective high pass filter.
Because conducting line 106 folds around dielectric substrate 102 and then electric wall 104 is disposed thereon, fabrication of high pass microwave line 100 is complicated. Further, it is very hard to provide an acceptable, clean connection between electric wall 104 and folding portion 110. When the connection has imperfections, the signal to noise ratio of high pass microwave line 100 decreases. Further, the structure of high pass microwave line 100 does not lend to easy incorporation into system on chip devices.
What is needed is a high pass filter that is useful in microwave applications for system on chip devices.

Integrated high pass filter for microwave system in package

United States of America as represented by Secretary of the Navy


A shelf unit for a kiosk which is configured to display items includes a plurality of dividers which maintain the items in respective positions on an insert disposed within a recessed top surface of the shelf. The insert includes a magnetically permeable material. A magnetic attraction exists between the dividers and the insert to secure the dividers in position. The dividers are movably positionable on the insert, with each of the dividers including a magnet and shielding material. The shielding material redirects magnetic flux emanating from the magnet toward the insert. The items are seated between the dividers on the insert.

Computer-enabled interactive kiosks offer retailers the ability to advertise, display products, and provide a wealth of product information, both visual and auditory, in a small, accessible installation. The multi-functionality of such kiosks provides retailers with opportunities to enhance the aesthetic appeal of its product offering for attracting customers, and can also foster a consistent set of visual and auditory features that customers may come to associate with a particular brand. As interactive kiosks are designed for, and often experience, extensive public use, the displayed objects can be moved from their assigned locations and manipulated in ways that change the overall appearance of the kiosk over time, to the detriment of the consistent "look" for which the specifications of the kiosk have been designed. Ways to prevent such detrimental changes to the appearance of the display are therefore sought.
What is therefore needed is an apparatus and method which displays products consistently within a kiosk installation and helps preserve the intended appearance of the kiosk as a whole.


A variable resistive memory device includes memory sectors, memory cells in each of the memory sectors, sub-wordlines including a first in signal communication with at least a first pair of the memory cells in a first sector and a second in signal communication with at least a second pair of the memory cells in a second sector, local bitlines where each is in signal communication a memory cell, a local bitline selecting signal generator in signal communication with local bitline selecting signal paths, a first local bitline selecting signal path in signal communication with a first pair of the local bitlines, and a second local bitline selecting signal path in signal communication with a second pair of the plurality of local bitlines, where a first of the first pair of local bitlines is in signal communication with a first of the first pair of the memory cells in the first sector and a second of the first pair of local bitlines is in signal communication with a second of the second pair of the memory cells in the second sector, and a first of the second pair of local bitlines is in signal communication with a second of the first pair of the memory cells in the first sector and a second of the second pair of local bitlines is in signal communication with a first of the second pair of the memory cells in the second sector.

The present disclosure relates to variable resistive memory devices and operating methods. More particularly, the present disclosure relates to variable resistive memory devices having a hierarchical wordline structure.
As the demands of high density and low power consumption continue to increase in memory devices, a new generation of memory devices has recently been introduced. Criteria for the new generation of memory devices include the nonvolatile characteristic for low power consumption, and easy scalability for high density. There have been several types of new generation memory devices, including Phase change Random Access Memory ("PRAM"), Resistive Random Access Memory ("RRAM"), and Magnetic Random Access Memory ("MRAM").
As shown in FIG. 1a, a unit memory cell is indicated generally by the reference numeral 10. The memory cell 10 includes a bitline ("BL") 18, a variable resistive material or part 12 connected to the BL, a switching element 14 connected to the variable resistive part, and a wordline ("WL") 16 connected to the switching element, where the switching element may be a transistor or a diode.
Depending on the variable resistive material, a memory device may be one of PRAM, RRAM or MRAM types. If the variable resistive material is defined by a lower electrode, an upper electrode, and a phase change material between the lower and upper electrodes, then the memory device is PRAM. If the variable resistive material is defined by a lower electrode, an upper electrode, and a Complex Metal Oxide ("CMO") material between the lower and upper electrodes, then the memory device is RRAM. If the variable resistive material is defined by lower and upper electrodes of ferroelectric material with an insulating material between them, the memory device is MRAM. A common characteristic of these three types of memory devices is that current flows from a bitline to a wordline or vice versa when a Write operation or a Read operation occurs. For simplicity of explanation, it may be hereinafter assumed that the variable resistive material is a phase change material, but the concepts extend to the other types of new generation memory devices as well.
Turning to FIG. 1b, a memory is indicated generally by the reference numeral 20. The memory 20 includes at least one cell array 22 having a plurality of memory cells 10 of FIG. 1a, a sense amplifier 24 connected to the cell 10 for providing a read current, and a write driver 26 connected to the cell 10 for providing a write current, which may be either a reset or a set current.
During a Write operation, the write current flows from write driver 26 towards the WL 16. If the write data is "1", a reset current flows from the BL 18 of FIG. 1a to the WL 16 of FIG. 1a through the unit memory cell 10. If the write data is "0", a set current flows from the BL to the WL through the unit memory cell 10. The reset current is larger than the set current.
During a Read operation, the read current flows from the sense amplifier 24 towards the WL. The sense amplifier detects the read current and amplifies the read current. The amount of current is dependent on a voltage difference between the BL and the WL.
Turning now to FIG. 2, a memory device is indicated generally by the reference numeral 100. The memory device 100 includes first and second memory sectors SEC1 and SEC2, memory blocks BLK1, BLK2, BLK3 and BLK4, a first main wordline driver 211 connected to a main wordline ("MWL") in the first sector SEC1, and a second main wordline driver 212 connected to a MWL in the second sector SEC2. Each block of each sector includes a sub-wordline driver 221 connected to the sub-wordline ("SWL") for the sector. Each memory block of the first sector includes a local bitline selection part 230, and each memory block of the second sector includes a local bitline selection part 220. A plurality of write driver and sense amplifier units 240 connect to a corresponding number of global bitlines ("GBL"), which connect to each block.
For an exemplary Write operation of the memory device 100, the dotted lines of FIG. 2 indicate non-activated lines and the solid lines indicate the activated lines. During this Write operation, one MWL in one memory sector (here, SEC1) is activated by a main wordline driver (here, 211). Each sub-wordline driver 221 of the memory blocks in SEC1 drives the SWL of the sector to reach VSS. The local bitline selecting parts 230 in SEC1 connect each local bitline ("LBL") in each memory block to a corresponding global bitline ("GBL") for that column or bit position. Thus, a voltage of the GBL delivered by the write driver is transferred to the LBL in each memory block in SEC1. Therefore, a write current due to the voltage difference between LBL and SWL flows from each LBL to the SWL through the variable resistive material in each memory cell. Due to the amount of the write current, the variable resistive material exhibits either high resistance or low resistance.
Unfortunately, since the write current can flow to one SWL through all of the memory cells connected to the one SWL, a voltage of the SWL rises. Due to this rise of the voltage of the SWL, the voltage difference between a bitline and the SWL is reduced and a desirable write current from a given LBL to the SWL may not flow. This can cause a Write operation to fail. In addition, a Read operation can fail for similar reasons.


Aqueous, fluorescent red ink jet inks which meet US Postal Service requirements for metered mail are disclosed and comprise an aqueous vehicle, a red or magenta pigment, a polymeric dispersant, a fluorescent dye and, optionally a hydrotrope additive.

This invention relates to aqueous printing inks and, more particularly, to aqueous, pigmented, red ink jet ink compositions which meet the stringent postal requirements and are thus suitable for use in printing postal indicia.
Ink jet ink printing is a form of digital printing in which droplets of ink are made to be ejected (i.e., "fire") from an orifice in a printhead or a spray nozzle in response to an electronic signal from, for example, a computer. Examples of ink jet printing include thermal ink jet printing, piezoelectric ink jet printing, continuous ink jet printing and air brush printing.
In the past decade, ink jet printing, particularly the thermal and piezo forms, has become extremely popular for home office, small office and personal printer applications, primarily due to its relatively low cost, speed and quite operation. In more recent years, the popularity of ink jet printing has increased even further due to the introduction of systems (printers, software, media and inks) offering very high quality (near photographic) color and graphics capabilities.
Postal authorities around the world require specialized indicia be used when the postage is applied to the mail by machine ("metered mail"), as opposed to when stamps are used for postage. Typically this indicia identifies the amount of the postage, the location of origin of the mail and often will identify the registered user of the device used to print the indicia. Because the machines that apply the postal indicia are, in effect, printing money, they are typically very strictly monitored. In addition, to avoid fraud, survive the elements, and to facilitate automated mail handling, the indicia must meet strict requirements. For example, the indicia must be readable after being immersed in water for 24 hours. It must be resistant to bleaching or removal with other solvents to prevent tampering with the postal amount. In the US and in some other countries, it must also be fluorescent on a variety of envelopes so that it is readable by a facer-canceller. It must be smudge and smear resistant to remain readable with repeated handling.
For many years, the postal indicia was applied with a stand alone metering device. The device was, in effect, a relatively sophisticated stamping device in which the postal amount was set by the user and the envelope was passed through the device to be metered and the appropriate postage applied. The ink used for the indicia was a fluorescent red ink applied with a stamp. Recently, ink jet based products have been introduced on the market for applying postal indicia to envelopes.
Despite its commercial success and Post Office approval, the inks used in the commercially available ink jet postal metering devices are inferior to the stamping inks previously used for postal metering in the sense that they do not satisfy some of the postal criterion mentioned above. For example, while the inks used in these commercial devices satisfy the fluorescence requirements, they do not perform well in the water immersion test or the bleach resistance test. Accordingly, there is a need in the art for aqueous red ink jet inks that can satisfy the demanding postal criterion for use in metering mail.

Aqueous ink jet inks for postal metering


A peptide comprising the amino acid sequence: U-O-X-glu-Z or O-X-glu-Z-ala-glu, wherein: U is an amino acid residue selected from val and ile; O is an amino acid residue selected from ala and thr: X is an amino acid residue selected from asp and glu: and Z is an amino acid residue selected from ile and val: the use of the peptide in the preparation of a vaccine; a composition for vaccination against malaria induced by Plasmodium falciparum, comprising such peptide in admixture with a pharmaceutically acceptable carrier; and a method of inducing immunity against malaria induced by Plasmodium falciparum, which comprises administering to a person in need of such immunity an effective amount of said composition.

Malaria is a wide spread disease, particularly in the developing countries, and scientists are constantly looking for new means to control the dangerous parasitic disease caused by plasmodial parasites. Among these parasites Plasmodium falciparum causes the most severe disease, responsible for the major part of the mortality due to malaria.
One strategy in combatting malaria resides in the use of a conventional vaccine based on attenuated or dead malaria parasites, but such approach has not been found to be practically feasible.
The alternatives are constituted by development of modern techniques, such as the manufacture of proteins by chemical synthesis or by DNA technology, such proteins as components in subunit vaccines being able to induce protective immunity against the parasite infection.
One strategy in the selection of antigenic sequences to be included in a potential subunit vaccine against Plasmodium falciparum malaria is to define the epitopes of antibodies which have the capacity to interfere with the parasite life cycle. Properly presented in immunogens these epitopes are expected to induce protective antibody responses. With regard to the asexual blood-stages of P. falciparum, the main attention in this context has been made to antibodies with capacity to inhibit merozoite reinvasion in vitro (Anders, R. F. (1985) Candidate antigens for an asexual blood-stage vaccine. Parasitol. Today 1, 152-155). However, antibodies which inhibit the cytoadherence of infected erythrocytes to endothelial cells (Howard, R. J. (1988) Malarial proteins at the membrane of Plasmodium falciparum-infected erythrocytes and their involvement in cytoadherence to endothelial cells. Prog.Allergy 41, 98-147; Udomsangpetch, R., Aikawa, M., Berzins, K., Wahlgren, M. and Perlmann, P. (1989) Cytoadherence of knobless Plasmodium falciparum-infected erythrocytes and its inhibition by a human monoclonal antibody. Nature 338, 763-765) or inhibit rosette formation between uninfected and infected erythrocytes (Carlsson, J., Holmquist, G., Taylor, D. W., Perlmann, P. and Wahlgren, M. (1990) Antibodies to a histidine-rich protein (PfHRP1) disrupt spontaneously formed Plasmodium falciparum erythrocyte rosettes. Proc.Natl.Acad. Sci. USA 87, 2511-2515) may also be of interest. Such antibodies are expected to interfere in vivo with the sequestration of late-stage infected erythrocytes (Howard, R. J. (1988) Malarial proteins at the membrane of Plasmodium falciparum-infected erythrocytes and their involvement in cytoadherence to endothelial cells. Prog.Allergy 41, 98-147; Carlson, J., Holmquist, G., Taylor, D. W., Perlmann, P. and Wahlgren, M. (1990) Antibodies to a bistidine-rich protein (PfHRP1) disrupt spontaneously formed Plasmodium falciparum erythrocyte rosettes. Proc.Natl.Acad.Sci. USA 87, 2511-2515).
The human monoclonal antibody (mAb) 33G2, obtained from an Epstein-Barr virus transformed B-cell originating from a Liberian P.falciparum-immune donor (Udomsangpetch, R., Lundgren, K., Berzins, K., Wahlin, B., Perlmann, H., Troye-Blomberg, M., Carlsson, J., Wahlgren, M., Perlmann, P. and Bj orkman, A. (1986) Human monoclonal antibodies to Pf155, a major antigen of malaria parasite Plasmodium falciparum. Science 231, 57-59) has several interesting biological properties. It inhibits both P.falciparum merozoite reinvasion in in vitro cultures (Udomsangpetch, R., Lundgren, K., Berzins, K., W ahlin, B., Perlmann, H., Troye-Blomberg, M, Carlson, J., Wahlgren, M., Perlmann, P. and Bj orkman, A. (1986) Human monoclonal antibodies to Pf155, a major antigen of malaria parasite Plasmodium falciparum. Science 231, 57-59) as well as cytoadherence of infected erythrocytes to melanoma cells in vitro (Udomsangpetch, R., Aikawa, M., Berzins, K., Wahlgren, M. and Perlmann, P. (1989) Cytoadherence of knobless Plasmodium falciparum-infected erythrocytes and its inhibition by a human monoclonal antibody. Nature 338, 763-765). The mAb, thus, has the capacity to interfere with the parasite erythrocytic life cycle at two potential target sites for protective antibodies in vivo (Anders, R. F. (1985) Candidate artigens for an asexual blood-stage vaccine. Parasitol. Today 1, 152-155) which makes the epitope recognized by the mAb of great interest with regard to vaccine development.
The mAb 33G2 was initially selected due to its reactivity with Pf155/RESA as detected by erythrocyte membrane immunofluorescence (EMIF) and immunoblotting (Udomsangpetch, R., Lundgren, K., Berzins, K., W ahlin, B., Perlmann, H., Troye-Blomberg, M., Carlsson, J., Wahlgren, M., Perlmann, P. and Bj orkman, A. (1986) Human monoclonal antibodies to Pf155, a major antigen of malaria parasite Plasmodium falciparum. Science 231, 57-59) but subsequent analyses with recombinant fusion proteins and synthetic peptides revealed that the antibody showed reactivity with a family of cross-reacting P.falciparum blood-stage antigens, including Pf155/RESA, Pf11.1 and Ag332 (Mattei, D., Berzins, K., Wahlgren, M., Udomsangpetch, R., Perlmann, P., Griesser, H. W., Scherf, A., M uller-Hill, B., Bonnefoy, S., Guilotte, M., Langsley, G., Pereira da Silva, L. and Mercereau-Puijalon, O. (1989) Cross-reactive antigenic determinants present on different Plasmodium falciparum blood-stage antigens. Parasite Immunol. 11, 15-30; Mercereau-Puijalon, O., Langsley, G., Mattei, D., Guilotte, M., Blisnick, T., Berzins, K., Griesser, H. W., Scherf, A., M uller-Hill, B. and Pereira da Silva, L. (1987) Presence of cross-reacting determinants on several blood-stage antigens of Plasmodium falciparum. UCLA Symp.Molec. Cell.Biol. 42, 343354; Udomsangpetch, R., Carlsson, J., W ahlin, B., Holmquist, G., Ozaki, L. S., Scherf, A., Mattei, D., Mercereau-Puijalon, O., Uni, S., Aikawa, M., Perzins, K. and Perlmann, P. (1989) Reactivity of the human monoclonal antibody 33G2 with repeated sequences of three distinct Plasmodium falciparum antigens. J. Immunol. 142, 3620-3626). A feature shared between these antigens is their contents of several tandemly repeated amino acid sequences containing regularly spaced pairs of glutamic acid (Mattei, D., Berzins, K., Wahlgren, M., Udomsangpetch, R., Perlmann, P., Griesser, H. W., Scherf, A., M uller-Hill, B., Bonnefoy, S., Guillotte, M., Langsley, G., Pereira da Silva, L. and Mercereau-Puijalon, O. (1989) Cross-reactive antigenic determinants present on different Plasmodium falciparum blood-stage antigens. Parasite Immunol. 11, 15-30; Favaloro, J. M., Coppel, R. L., Corcoran, L. M., Foote, S. J., Brown, G. V., Anders, R. F. and Kemp, D. J. (1986) Structure of the RESA gene of Plasmodium falciparum. Nucleic Acids Res. 14, 8265-8277; Scherf, A., Hilbich, C., Sieg, K., Mattei, D., Mercereau-Puijalon, O. and M uller-Hill, B. (1988) The 11-1 gene of Plasmodium falciparum codes for distinct fast evolving repeats. EMBO J. 7, 1129-1137). These dimers of glutamic acid were suggested to be the structures responsible for the antigenic cross-reactions seen between the three antigens (Mattei, D., Berzins, K., Wahlgren, M., Udomsangpetch, R., Perlmann, P., Griesser, H. W., Scherf, A., M uller-Hill, B., Bonnefoy, S., Guilotte, M., Langsley, G., Pereira da Silva, L. and Mercereau-Puijalon, O. (1989) Cross-reactive antigenic determinants present on different Plasmodium falciparum blood-stage antigens. Parasite Immunol. 11, 15-30; Merecereau-Puijalon, O., Langsley, G., Mattei, D., Guilotte, M., Blisnick, T., Berzins, K., Griesser, H. W., Scherf, A., M uller-Hill, B. and Pereira da Silva, L. (1987) Presence of cross-reacting determinants on several blood-stage antigens of Plasmodium falciparum. UCLA Symp.Molec. Cell.Biol. 42, 343-354; Udomsangpetch, R., Carlsson, J., W ahlin, B., Holmquist, G., Ozaki, L. S., Scherf, A., Mattei, D., Mercereau-Puijalon, O., Uni, S., Aikawa, M., Berzins, K. and Perlmann, P. (1989) Reactivity of the human monoclonal antibody 33G2 with repeated sequences of three distinct Plasmodium falciparum antigens. J. Immunol. 142, 3620-3626). Inhibition with synthetic peptides of the mAb 33G2 binding in EMIF showed that peptides corresponding to Ag332 repeat sequences were the most efficient inhibitors, suggesting that Ag332 was the original target for the antibody (Udomsangpetch, R., Carlsson, J., W ahlin, B., Holmquist, G., Ozaki, L. S., Scharf, A., Mattei, D., Mercereau-Puijalon, O., Uni, S., Aikawa, M., Berzins, K. and Perlmann, P. (1989) Reactivity of the human monoclonal antibody 33G2 with repeated sequences of three distinct Plasmodium falciparum antigens. J. Immunol. 142, 3620-3626).
The major object of the present invention is to provide new peptides capable of inducing immunity against malaria.
Another object of the invention is to provide new compositions for vaccination against malaria comprising such peptide.
Yet another object of the invention is to provide a method of inducing immunity against malaria.

Peptides comprising a protective epitope from blood stages of plasmodium falciparum


An electrical connector is shown for terminating both signal and coaxial cable. To maintain the same interface pattern, the signal pins for the coaxial cable include contact portions with angled connection sections and ground contacts for contacting the shielding braid of a cable are laterally offset. The housing includes channels to arrange the coaxial cables with the signal contact termination portions and with the ground contact termination portions.

1. Field of the Invention
The invention relates to an electrical connector including coaxial and signal contacts.
2. Description of the Prior Art
In the field of coaxial connectors, a solid core wire typically is positioned concentrically of a first portion of surrounding insulation, a shielding braid surrounding the first portion of insulation, and a second portion of insulation surrounding the shielding braid. Normally, such a cable is terminated by stripping a portion of the outer insulation to a position exposing a length of the shielding braid. The inner insulation is then stripped to expose a portion of the inner conductor. The shielding braid can be interconnected to an outer shield member by a crimp section, by a compression fit outer shield housing, or by soldering the shielding braid to the outer shield member. This interconnection is quite labor intensive and time consuming, and thus very expensive to make. Furthermore, it typically requires the assembly under controlled circumstances, not in a field installation.
It is also necessary, in some circumstances to provide such an interconnection for signal conductors and coaxial cable on a centerline spacing which is already a standardized interface. However, this difficult, as the width of the coaxial cable alone, does not allow such a pitch.


A pixel structure comprises an epitaxial layer (1) of a first conductivity type. A photo-sensitive element comprises a first region (4) of a second conductivity type and a second region (3) of the first conductivity type positioned between the epitaxial layer (1) and the first region (4). A charge storage node (ø2) is arranged to store charges acquired by the photo-sensitive element, or to form part of a charge storage element. A third region (2) of the second conductivity type is positioned between the charge storage node and the epitaxial layer. The pixel structure further comprises a charge-to-voltage conversion element (13) for converting charges from the charge storage node to a voltage signal and an output circuit (21, 22) for selectively outputting the voltage signal from the pixel structure.

An image sensor comprises an array of pixel structures. The array can be operated with a rolling shutter or with a global shutter. For a rolling shutter, image acquisition is briefly shifted in time for every row of the pixel array. This leads to deformation of the scene. For a global shutter, all pixels are exposed together (synchronously). A global shutter is required to record fast moving subjects, or when the camera itself is moving. This is typically needed in high speed imaging applications or in machine vision. A global shutter pixel requires a memory element inside the pixel array, to store the captured image during the frame readout time. This stored pixel sample is then read out row-by-row while the next image is captured.
In some known global shutter pixel configurations, charges are stored in a potential well, in the charge domain. This charge storage node can unintentionally collect additional photoelectrons during a charge storage phase of operation. These additional photoelectrons are intended to be collected by the photodiode rather than by the storage node, but some charges will diffuse and be collected by the storage node instead. This results in a parasitic light sensitivity of the charge storage nodes.
FIG. 1 shows a global shutter pixel with in-pixel charge storage under a storage gate ø2. A cross-section is shown of the photodiode, charge transfer gates ø1, ø2 and ø3, the floating diffusion fd, the reset transistor RST, and the anti-blooming charge drain AB. The source follower and select transistor are shown on circuit level only. The photodiode is a pinned photodiode in which the surface is pinned at ground potential by a p+ surface implant layer. This p+ implant layer is connected to ground potential (not shown in the drawing). The diode itself is formed by an n-type implant under this pinning implant, which forms a junction with the p+ surface implant and the p-epitaxial layer. Charges are transferred from the photodiode to the storage gate ø2 via the transfer gate ø1 at the end of the exposure time. For readout, the floating diffusion fd is reset through RST, and then the charge is transferred from ø2 to fd by pulsing gates ø2 and ø3.
After the signal has been sampled under ø2, and while the signal is stored under ø2, the next image is acquired. Photo-generated electrons are created in the substrate. The electrons generated in the p-epitaxial layer are to be collected by the photodiode. Some are generated inside the depleted area of the photodiode and are immediately collected. Other charges are generated outside of this depletion area and will diffuse until they reach the electric field formed by the photodiode or by another junction or gate in the structure. Two such electrons e− are shown. One electron diffuses and is collected by the photodiode. Another electron however diffuses until it is collected by the storage gate ø2, which is biased at a high potential during storage. There is no electrical barrier for this electron to diffuse to this gate. A significant fraction of electrons are collected by this storage gate. A light shield 11 can be used to shield the storage node. This is only partially effective due to the random diffusion of the electrons.
FIG. 2 shows a known improvement intended to avoid charge diffusion to the storage nodes. This improvement is described, for example, in U.S. Pat. No. 6,225,670, provides a higher p dose under the storage node. The concentration difference between the p-well layer and p-epitaxial layer is sufficient to create a small potential barrier. The potential difference is given by:
  ϕ  =            kT      q                  ln                    (                              N            a            +                                N            a                          )            where Na and Na+ are the acceptor concentrations for the p and p+ regions, and kT/q is the thermal voltage (k=Boltzman constant, T=absolute temperature, q=elementary charge). Typical p-well concentrations are 1E17/cm3, while typical epitaxial layer concentrations are 5e14/cm3, forming a barrier of 134 mV at room temperature. FIG. 3 shows the electrostatic potential along the cross-sections A-A′, B-B′ and C-C′ in FIGS. 1 and 2. Another example of the use of a dopant profile to shield unrelated junctions in the pixel from charge collection is shown in US Patent application US 2007/0109437A1.
The present invention seeks a way to further improve shutter efficiency by reducing the parasitic light sensitivity of the pixel structure.