Disclosed is a structure and process for incorporating air or other gas as a permanent dielectric medium in a multilevel chip by providing CVD diamond as a semi-sacrificial interlevel and intralevel dielectric material. The semi-sacrificial dielectric is subsequently at least partially removed in an isotropic oxygen etch. A variation of the disclosure includes providing a final, permanent CVD diamond encapsulant to contain the gaseous dielectric medium within the chip.

1. Field of the Invention
This invention relates to high density integrated circuit (IC) devices. More particularly, this invention relates to very high density multilevel interconnect electronic structures, and processes of fabricating such structures, which are comprised of alternating via levels and wiring levels embedded in a gas dielectric medium, suitable for mounting on carriers such as multichip modules.
2. Background Art
The continuing drive toward reduction in dimensions and increase in the number and density of components within IC chips is inspired by increasingly more aggressive requirements of memory and logic. Smaller chip features provide higher bit density, lower operating voltages, lower energy consumption and faster device speed. Increased also are problems associated advanced IC miniaturization and the attendant closer proximity of circuit features to one another, including risk of shorting, crosstalk and capacitative coupling, among others. The highly dense integrated circuits of the future will require even narrower and longer conductor lines, tighter pitch via interconnects and lower dielectric constant values for the insulating medium, especially in the wiring levels. The lower the dielectric constant of the insulating medium, the faster the circuit speed.
As the design demands for the CMOS IC in particular become more aggressive, the need to reduce the dielectric constant of the insulating medium to a value closer to the ideal value of air, 1.0, becomes a necessity. Attempts have been described in the art to incorporate air into a solid dielectric matrix, as in the form of foam or microspheres. More recently, attention has turned to the possibility of employing air alone or some other gas as the dielectric medium in at least one level.
Copending application Ser. No. 09/133,537 to Jagannathan et al filed Aug. 13, 1998 and assigned to the same assignee as the present invention describes the incorporation of air as a dielectric medium. The application describes the use of a fluoride-containing organic solvent for removing silicon-containing temporary dielectric material. The removal of the silicon-containing dielectric material leaves air-filled gaps to function as a permanent dielectric medium.
U.S. Pat. No. 5,789,559 issued Aug. 25, 1998 to Subhas Bothra and Liang Q. Qian describes the formation of air dielectric between metallization layers as a result of the removal of a temporary solid dielectric material by a liquid etchant, buffered hydrofluoric acid (BHF).
An article on pages 575-585 of the IBM Journal of Research and Development, Volume 42, No. 5, September. 1998, xe2x80x9cElectrochemical processes for advanced package fabricationxe2x80x9d, coauthored by S. Krongelb, J. A. Tornello and L. T. Romankiw includes a description of a multilevel interconnect IC in which polyimide functions as a temporary dielectric. The polyimide was removed by ashing in an oxygen-containing plasma. The IC chip also includes copper wiring, which was plated.
An article on pages 49-51 of the journal Electrochemical and Solid State Letters, published by the Electrochemical Society, Inc. 1(1), 1998, xe2x80x9cAir Gaps for Electrical Interconnectionsxe2x80x9d, coauthored by Paul L. Kohl, Qiang Zhao, Kaushal Patel, Douglas Schmidt, Sue Ann Bidstrup-Allen, Robert Shick and S. Jayaraman describes the removal of a sacrificial polymer by thermal decomposition within an encapsulated chip. The byproducts escape by diffusing through the encapsulant
In the Technology News column on page 38 of the March 1999 edition of the journal Semiconductor International, Editor-in-Chief Peter Singer describes Toshiba""s use of carbon dioxide gas dielectric in the wiring levels of an IC. The carbon dioxide is formed when the layer of carbon, which has been sputtered, is heated at 450 degrees C. in an oxygen atmosphere, resulting in the diffusion of oxygen to the carbon, where they combine to form CO2.
An article on pages 51, 52, 54, 57, and 58 of the February, 1999 issue of the journal Solid State Technology, xe2x80x9cAir gaps lower k of interconnect dielectricxe2x80x9d, coauthors Ben Shieh, Krishna Saraswat, Mike Deal and Jim McVittio describe results of their modelling of air dielectric in structures having a variety of aluminum conductor line dimensions. Their simulation predicts a 40%-50% reduction in capacitance due to the air dielectric.
In the present invention, wet processing can be limited to photolithographic processes, such as resist removal, which are conventionally used successfully and without contaminating the IC structure. Rather than using aggressive solvents to remove a temporary, sacrificial dielectric material, an isotropic oxygen etch is used to remove the sacrificial dielectric material cleanly. Whereas electroplating can be used to deposit such metals as copper and gold for wiring and interconnect vias in the present invention, dry deposition is preferred because extra steps such as those involved in establishing a barrier to electromigration of the metal into silicon are not required and because some useful metals and alloys are not amenable to plating. A wide variety of dielectric gasses can be protectively incorporated into the IC chip of the present invention High temperature decomposition techniques play no role, nor is it necessary to fabricate passivation layers, such as on the substrate level. The present invention uniquely uses diamond, preferably deposited by CVD, rather than, for example, a polymer or a silicon oxide as the temporary, sacrificial dielectric layer material. Since CVD diamond is a stronger material than polyimide or other dielectric polymer, use of the CVD diamond in the present invention will facilitate planarization by chemical-mechanical polishing (CMP). CVD diamond has the further advantage superior ability to conduct heat away from the IC chip which it encloses, in particular when a limited amount of CVD diamond is permitted to remain within the fabricated structure.
The present invention includes the removal of sacrificial CVD diamond in a gas etchant, leaving gas-filled gaps to function as the permanent dielectric medium in, for example, a CMOS IC, a procedure not described in the art. The process of the present invention avoids any attack on or contamination of the elements of the IC structure and obviates any need to protect the gate level substrate by passivation, allowing the gate level the benefit of the low dielectric gas medium and avoiding passivation steps. Furthermore the present invention describes a means of encapsulating the gas dielectric and an encapsulated CMOS IC not found in the art. The encapsulant eliminates diffusion of moisture or impurities into the encapsulated structure and confines the gas within. Several different gases can be used as alternative permanent dielectric media. These and other advantages and distinctions will be more fully evident infra.
It is therefore an object of the invention to provide a multilevel interconnect CMOS IC chip having a gas insulating medium whose dielectric constant approaches or equals the ideal value of air.
It is a further object of the invention to employ a CVD diamond sacrificial dielectric in conjunction with removal of the sacrificial dielectric by an isotropic oxygen etch to produce a very low-k IC chip.
It is a further object of the invention to provide an encapsulated multilevel interconnect CMOS IC chip having a gas insulating medium which is protected from exchange of material with the external ambient and away from which heat is readily conducted.
It is a further object in an alternate mode of the invention to permit CVD diamond to remain in selected areas of the chip in order to provide additional structural support and thermal conductivity.
It is a further object in an alternate mode of the invention to provide strategically located support structure in the form of pillars or studs in the process of forming and encapsulated structure.
These and other objects are achieved according to the present invention in which, except for standard photolithographic steps, dry processing steps produce a high density CMOS IC which includes a gaseous dielectric medium interlevel and intralevel. The fabrication of the IC involves first including diamond or preferably CVD diamond as a sacrificial dielectric material. Upon completion of the chip, prior to the deposition of final encapsulant, the sacrificial dielectric is removed harmlessly and selectively through openings in a hard mask top coat using an isotropic oxygen etch. Without compromising the electrical or mechanical integrity of the chip structures the removal of the temporary, sacrificial dielectric material leaves behind regions in the structure which are filled with a permanent, gas dielectric medium. The sacrificial dielectric medium is also referred to herein as semi-sacrificial, as it is not necessarily the case that all of it must or should be removed from a particular IC configuration, since the dielectric constant of CVD diamond is known to be low at a value of about two.
In an embodiment of the present invention, the high density CMOS IC is sealed off from the ambient by an encapsulant. The seal assures a stable gaseous dielectric environment comprising such gases as air, CO2, nitrogen, inert gasses such as argon, helium, or others, and mixtures thereof. The encapsulant may also be controllably deposited in selected dielectric regions within the structure for additional mechanical support, leaving the remaining dielectric regions occupied by the air or other gas.

Semi-sacrificial diamond for air dielectric formation

International Business Machines Corporation


A light emitter, being an LED or laser diode, is disposed above a base substrate, and a coating material containing a dye compound, such as an epoxy material containing a fluorescent or luminescent substance, is applied over the light emitter. The base substrate includes a raised platform on which the light emitter is mounted, such that the light emitter is supported at a prescribed distance from the surrounding base substrate. The device allows the dye compound within the coating material to settle into the recessed base substrate surrounding the platform and leave the sides of the light emitter able to retain only a coating of the dye comparable in thickness to that coating remaining on the upper surface of the light emitter, in order to improve the uniformity of the light distribution pattern emitted from the device.

Light emitting diodes (LEDs) are very well known in solid state illuminating devices, commonly used for illuminators, display components and indication devices. Early LEDs provided radiation in the high frequency end of the visible spectrum, namely as red light. More recently, LEDs have been developed that operate efficiently in the higher frequency portion of the visible spectrum, namely to emit blue light. Such devices employ layers of luminescent or fluorescent materials, for example phosphor, overlying the LED die and serving to shift the wavelength of the light emitted from the die, the radiation being re-emitted from the intermediate phosphor layer at a longer wavelength.
As an example, a blue LED such as a gallium nitride (GaN) die, can be used to provide a white LED lamp by positioning a layer of phosphor dye over the LED die. This is then encapsulated in a standard clear epoxy lens, and the LED then connected and powered in the conventional manner. The phosphor layer serves to absorb, shift, and re-emit a broad band yellow-green light, as well as some unabsorbed original blue light which passes through the phosphor layer. The combination radiation is emitted through the epoxy lens and results to a viewer in a perceived emission of white light.
Various types of fluorescent material have been tested and used in providing a range of colour mixtures, and devices are now available that can produce light in almost any desired colour.
A further approach has been developed in the prior art for employing such fluorescent or luminescent materials in LED devices. In U.S. Pat. No. 5,847,507 (Hewlett Packard Co.), a process and apparatus is described in which a lens incorporating a fluorescent dye is over-moulded to a short wavelength light emitter such as a blue LED or a laser diode placed within a reflector cup. The concentration of the dye within the lens can be varied to control the extent of a region within the lens where the majority of the radiation is re-emitted, such that the remaining portion of the lens can fulfil its primary duty of focussing the light.
The dye used for "doping" the epoxy material in constructing this type of LED device can be provided by way of an inorganic dye material, generally a powder, or by way of an organic dye material, generally a liquid. Studies by the inventor of the present invention have indicated that the use of organic dyes appears to be more efficient than that of inorganic compounds, largely because the powder particles tend to settle within the hardening epoxy material, so tending to affect the homogeneity of the phosphor-containing portion of the lens. These studies have shown that the LED devices so produced can therefore suffer from problems of non-uniformity in their colour. Portions of the radiation pattern of the LED as perceived can differ in colour from other portions, and in particular, the outer part of the radiation pattern can tend to differ from the colour of the on-axis radiation emitted.
As an example, in the construction of an LED device consisting of a blue LED with YAG:Ce3+ phosphor, a yellow ring can be seen around the perimeter of the radiation pattern. Therefore, viewing the lamp on-axis and off-axis can result in perception of different colours. The reason for this artefact has been found to be that the quantity of luminescent or fluorescent material surrounding the LED die tends to be non-uniform, due to the method of construction of such devices. The doped epoxy material is conventionally applied over the LED die in a quantity such that it fills the reflector cup in which the die is mounted. The phosphor particles contained in the epoxy material then settle around the contours of the LED die and reflector cup as the epoxy cures. Due to the contours of the device, and particularly due to the generally annular space around the LED die, excessive dye material tends to collect at the sides of the LED, in comparison with that which remains overlying the surface of the LED. For this reason, the wavelength shift of the light emitted from the device when seen from the side differs from that when viewed along a line parallel to the central axis.
It is an object of the present invention to address the aforementioned drawbacks and to provide an improved apparatus and method in the field of light emitting devices.

Light emitting devices with a phosphor coating having evenly dispersed phosphor particles and constant thickness

Avago Technologies General IP (Singapore) Pte. Ltd.


An RF filter which includes a circuit board connected to an internal frame has two end connectors connected to the frame, with a protective casing connected to the internal frame and the end connectors. Insulators in each end connector are shaped to form air pockets between the air pockets and the outer conductor portion of the end connectors. A plurality of O-rings are disposed in various locations on the insulators to prevent moisture from entering the filter. The RF filter passes the SCTE Red Dye Test and limits return loss to better than negative 20 dB.

It has been the custom for many years in the CATV trap and filter industry to focus upon the hermesticity of the device housing when designing the connectors at each end of the housing. This has led to a preference for moisture blocking insulative materials such as glass and thick cross-section pieces of rubber. While these materials typically are very good at preventing moisture from entering the device housing, they create very low impedance zones within the connections which are not matched to the 75 ohm impedance of the CATV system.
While this does not prevent signal transmission to a debilitating degree in analog systems, it does cause a great deal of signal reflection, i.e., high return loss, which can cause debilitating interference in systems which operate digital programming and data within their bandwidth. While some of this reflection may be compensated for by selective tuning of the filter circuit within the housing, it is not sufficient if return loss values of −20 dB or less, i.e., −30 dB, −40 dB, etc., are desired. To achieve these improved levels of return loss, it is necessary to impedance match the connector portions of the housing as close to 75 ohms as possible.
U.S. Pat. No. 6,888,423 (Tresness et al.) and U.S. Pat. No. 6,323,743 (Zelenz et al.) both disclose a solid polypropylene insulator 96b at one end of the housing and a solid low density polyethylene insulator 95 at the other end.
U.S. Patent Application Publication No. 2005/0162238 (Ho) discloses an insulating ring 42 secured within a separating part 41 at one end of the housing.
U.S. Pat. No. 6,794,957 (Shafer et al.) discloses a solid insulator 24 at one end of the housing and a solid deformable rubber seal 20 and a solid insulator 22 at the other end.
U.S. Pat. No. 5,498,175 (Yeh et al.) discloses two insulating members 53 which go on both ends of a contact member 20, with each insulating member 53 consisting of an insulating sleeve 30, a silicone resilient member 52, and an insulating cap 50.
U.S. Patent Application Publication No. 2005/0001697 (Gould et al.) discloses a solid polypropylene insulator 96b at one end of the housing and a solid low density polyethylene insulator 95 at the other end.

Impedance matched waterproof connector for CATV filter housing


The present invention discloses catalytic cracking apparatus and process, which are useful for catalytic cracking of heavy oils with a high heavy oil conversion, a high propylene yield and low dry gas and coke yields.

Heavy oil catalytic cracking is an important process for producing lower olefins such as ethylene, propylene and butylene.
The commercial process of heavy oil catalytic cracking to produce lower olefin includes those disclosed in U.S. Pat. No. 4,980,053, U.S. Pat. No. 5,670,037 and U.S. Pat. No. 6,210,562. These processes use a single riser reactor or a combination of a single riser reactor and a dense bed and have problems of high dry gas and coke yields.
Recently, more and more attentions are paid to the technology of using two risers to produce propylene.
CN101074392A discloses a method for producing propylene and gasoline diesel-oil by two-section catalyzed cracking style, which is carried out by adopting two-section lift pipe catalyzing process and catalyst with molecular sieve, taking heavy petroleum hydrocarbon or various animal and vegetable oils containing hydrocarbon as raw materials, optimization combining by charging style for various reactants, and controlling proper reactive conditions. It can improve propylene and light-oil recovery rate and quality, and inhibit to generate dry gas and coke. Said method has a low propylene yield and a low heavy oil conversion capability.
CN101293806A discloses a catalytic conversion method for improving the yield of low-carbon olefin, which comprises the following steps: hydrocarbon oil raw material is injected into a riser or/and a fluidized bed reactor via a feed nozzle, comes into contact with catalyst containing shape-selective zeolite with an average pore size being smaller than 0.7 nm and reacts; gas rich in hydrogen is injected into the reactor; reaction oil gas and spent catalyst after reaction are separated, wherein the reaction oil gas is separated to obtain a target product containing ethylene and propylene; and the spent catalyst is returned to the reaction for reutilization after being stripped and regenerated. By injecting gas rich in hydrogen, the method can remarkably inhibit reconversion reaction of the generated low-carbon olefin to improve the yield of low-carbon olefin, particularly of propylene. Said method has a limited effect of decreasing the dry gas yield and increasing the heavy oil conversion capability.
CN101314724A discloses a method for catalytically transforming bio-oil and mineral oil combination, which comprises the following steps: contacting bio-oil and mineral oil with catalyst containing modified beta-zeolite in a compound reactor to carry out catalytic cracking reaction, separating the reaction resultant with the spent catalyst, processing the spent catalyst by stripping and burning and adding into the reactor for recycling, introducing the separated resultant from the reactor, and distilling to obtain target product low-carbon alkenes, gasoline, diesel and heavy oil. Said method has a high dry gas yield and a low heavy oil conversion.

Catalytic cracking apparatus and process


The present invention relates to a method for forming a GaN-based nitride layer comprising a first step of forming a first layer comprising SiaCbNc (c,fc>0, a≧0) on a sapphire substrate and a second step for forming a nitride layer comprising a GaN component on the first layer comprising SiaCbNc (c,b>0, a≧O).

In preparation of semiconductor devices, a substrate comprising sapphire (Al2O3) or silicon carbide (SiC) is generally used to grow a GaN-based nitride layer. However, these substrates are different from the GaN-based nitride layer in material properties such as lattice constant and thermal expansion coefficient and thus, it is difficult to grow a high quality GaN-based nitride layer. There have been developed and disclosed many techniques for growing the GaN-based nitride layer.
One of the representative methods is using a buffer layer. According to this method, a Al(x)Ga(y)In(z)N film (0≦x≦1, 0≦y≦1, 0≦z≦1, x+y+z=1) is grown in a single or various composition at 450° C. to 600° C., followed by raising temperature to form the Al(x)Ga(y)In(z)N (0≦x≦1, 0≦y≦1, 0≦z≦1, x+y+z=1) into a nuclei, which is used as a seed to grow a high quality GaN-based nitride layer. Also, a AlN buffer layer (Japanese Patent publication No. 62-119196), a LT-AlGaN buffer layer (U.S. Pat. No. 5,290,393/Japanese Patent publication No. 4-297023: 1991), a LT(low temperature)-AlGaInN buffer layer (U.S. Pat. No. 6,508,878), a LT-AlInN buffer layer and the like are used. However, when a GaN-based nitride layer is grown by these methods, the grown GaN-based nitride layer has a dislocation density of 1010 to 1012/cm2.
Also, unlike the above-described examples, in which a buffer layer is grown on a sapphire substrate at a low temperature, a GaN-based nitride layer may be directly grown on the substrate at a high temperature. However, there is much room for improvement.
FIG. 1 is a view to explain a method for forming a GaN-based nitride layer on a sapphire substrate according to the prior art, in which a GaN or AlGaN or InGaN buffer layer 11 is grown on a sapphire substrate 10 at a low temperature (typically 500° C. to 800° C.) and a GaN film 12 is grown at a high temperature of about 1050° C. In this case, the GaN or AlGaN or InGaN buffer layer 11 grown at a low temperature is deformed, when the temperature is raised, to have a 3-dimensional shape. The deformed buffer layer 11 serves to buffer strain between the GaN film 12 and the sapphire substrate 10. However, fundamentally, the GaN or AlGaN or InGaN buffer layer 11 also has a big lattice mismatch with the lattice of the sapphire substrate 10 and induces lattice mismatch in the GaN film 12 grown thereon (lattice dislocation density: 1010 to 1012/cm2).
Therefore, in order to reduce such lattice mismatch and improve properties of a thin film to be grown, it is preferable to use a substrate having a lattice corresponding to that of GaN, instead of the sapphire substrate which has been commonly used. However, it is matter-of-fact impossible.
A group where the present inventors also belong to has found that when a buffer layer of a SiC thin film, instead of Al(x)Ga(y)In(z)N (0≦x≦1, 0≦y≦1 ,0≦z≦1, x+y+z=1), which has been disclosed, is formed on a sapphire substrate and a GaN-based nitride layer is formed thereon, the formed GaN-based nitride layer has excellent properties and filed an application based on this discovery (Korean Patent Application Nos. 10-2003-52936 and 10-2003-85334).

Method for material growth of GaN-based nitride layer


A quick release bolt for securing two or more parts together is disclosed. The quick-release bolt includes a threaded end and a slotted end opposite the threaded end. The slotted end includes a slot extending across a diameter of the bolt and extending axially into the bolt. A release/lock plate is pivotally attached to the bolt within the slot in the bolt by a pin that is attached to the bolt. The pin extends transversely through the slot in the bolt and passes through a slot in the release/lock plate. The release/lock plate may be pivoted between locking and releasing positions when the bolt is loosened only about one-half to one-quarter of a turn from a tightened position.

Peristaltic pumps are well-known devices which transfer fluid through an elongate flexible tube by compressing a portion of the tube, and pushing the fluid through the tube using such compression. Peristaltic pumps; are commonly used for transferring fluids such as ink for printing or for transferring fluids such as blood in medical equipment. Peristaltic pumps may also be used to transfer fluids such as cleaning agents, coolants, slurries or liquid adhesives, just to name a few of the many fluids that can be transferred with such pumps. One advantageous feature of peristaltic pumps is that the fluid does not contact the pump mechanism since the fluid is always confined within and moved through the flexible tube. Therefore, peristaltic pumps may be used to transfer corrosive or caustic solutions or other hazardous fluids without affecting the pump mechanism.
In a typical peristaltic pump, the tube is compressed by one or more rollers that are driven by an electric or air-powered motor. Each roller compresses the tube as it moves along the length of the tube. Also typically, the flexible tube is fed through the pump along a generally U-shaped path or alternatively along a substantially straight arc-shaped path (in the case of a pass-through pump) so that the U-shaped or arc-shaped portion of the tube overlaps a portion of a path traveled by the rollers. Such arrangements have numerous disadvantages. For example, the tube can undesirably creep through the pump during operation. of the pump, requiring either periodic adjustment of the tube, or a separate clamping device to prevent such creep of the tube. A U-shaped or substantially straight arc-shaped tube path in a peristaltic pump provides a small contact area between the pump rollers and the tube, as the rollers are only in contact with the tube over a small portion of the overall path of travel of the rollers. As a result, depending on the flow rate requirements imposed on the pump, there can be substantial fatigue imposed on the tube. The use of additional rollers may partially correct this problem, but causes additional wear on the tube and adds cost and complexity to the pump.
In many peristaltic pumps using a U-shaped tube path, the flexible tube is oriented such that the fluid flowing into the pump flows in a direction opposite to that of the fluid flowing out of the pump. In such an arrangement, additional space and tube length is required if the pump is to be disposed along a line leading from the source of fluid directly to the destination to which the fluid is being pumped, as the tube must turn 90.degree. to enter the pump and the tube must also turn 90.degree. to exit the pump. As will be appreciated, these turns could also cause kinking of the flexible tube that would either interrupt or at least interfere with the free flow of fluid. Such kinking is highly undesirable and could be dangerous in some applications.
The housing of a typical peristaltic pump as well as: the components located within the housing can be complex and expensive to manufacture, especially if a large number of rollers are used in the pump. Therefore, there is a need for a peristaltic pump that is economical to manufacture, durable, compact and capable of reliably and efficiently pumping fluid.

Quick-release bolt for use with pump housing


A shared resource system, method of sharing resources and services and a computer program product therefor. Client computers communicate with at least one provider computer that selectively makes resource capacity available to the client computers. The client computers and provider computer pass messages to each other negotiating access to provider resources and services. The provider computer(s) notifies each requesting client computer of any potential conflicts with any portion of the requested capacity in confirmation qualification messages.

1. Field of the Invention
The present invention is related to allocating resources amongst multiple computers and more particularly to managing and allocating resources for cloud computing.
2. Background Description
Recently, cloud computing has offered great opportunities for a broad range of applications. Cloud service providers (e.g., with mainframe computers), users/clients connected together over networks constitute a client-cloud system wherein the cloud computers provide services and resources and handle data-intensive computing tasks for the clients. This has allowed user clients to become much more lightweight and mobile, while still to having require access to resources managed by the resource providers.
Typically, users may request allocation of available resource capacity from one or more providers simultaneously or essentially simultaneously, i.e. within a given time interval. A typical state of the art resource protocol for allocating resources has two phases: the selection phase where the user selects available resources; and, the confirmation or commit phase, the user confirms the resource allocation. The selection phase is first come, first served. So, when multiple users select (request) the same resource(s), the first user who commits the selection receives the resource i.e., confirms. Frequently, however, there is a delay between selecting/requesting a resource or resources and confirmation/commit that causes a conflict. Conflicts arise because during that delay resource availability information may become stale. This can result in what is known as deadlock and/or livelock.
Deadlock occurs when a user with a committed resource (locked) is waiting for another requested resource, e.g., where the other resource is committed to another user and the first user is waiting for that committed resource to become available. Deadlocks can be avoided by refusing to allocate less than all of the requested resources or services, i.e., all or nothing.
Livelock occurs when multiple users requesting multiple resources are each granted access to some, but not all of the requested resources. In a sort of round robin game of resource tag, while one user is deciding to commit desired capacity, some or all of that desired capacity can be allocated elsewhere. So, to avoid having capacity allocated elsewhere, the user may have to hurry decisions after selecting resources. Otherwise, with the requested capacity allocated elsewhere, the user may take several iterations (messages with the providers) negotiating to recover from stale information. Consequently, the negotiation messages can waste valuable computing time and resources, and therefore, may be expensive.
State of the art approaches for reducing the number of messages required by negotiations include Order-based Deadlock Prevention Protocols (ODP2) and back-off mechanisms. Examples of these approaches are described by Jardine et al. "Livelock avoidance for meta-schedulers," Proceedings of International Symposium on High performance Distributed Computing. (2001); and by Hah et al., "A SNAP-based community resource broker using a three-phase commit protocol: a performance study," The Computer Journal (2005). These state of the art approaches do not make users aware of any other users that may be concurrently negotiating for the same resources. Instead, only when allocation fails do users receive messages that indicate committing the request failed. Consequently, these state of the art negotiations require several messages and allow users too little time to make allocation decisions.
Thus, there is a need for a reducing negotiations required in allocating resources to users and more particularly in facilitating resource allocation with minimal conflicts, without rushing user decisions.

System, method and program product for allocating resources and services

International Business Machines Corporation


An optical head device and an optical recording and reproducing apparatus using this optical head device, which can record information and reproduce the recorded information at any of optical recording media, such as a next generation optical recording medium, in which the wavelength of the light source is made to be shorter, the numerical aperture of the objective lens is made to be higher, and the thickness of the recording medium is made to be thinner, and conventional recording media of DVD and CD standards, are provided. A light having wavelength of 405 nm, emitted from one of optics, is inputted to an objective lens as a collimated light, and is focused on a disk having thickness of 0.1 mm. A light having wavelength of 650 nm, emitted from the other of optics, is inputted to the objective lens as a diverged light, and is focused on a disk having thickness of 0.6 nm. A spherical aberration, which remains for the light having wavelength of 650 nm, is decreased by the change of the magnification of the objective lens, further the decreased spherical aberration is debased by using a wavelength selective filter.

The present invention relates to an optical head device and an optical recording and reproducing apparatus using this optical head device, which records information and reproduces the recorded information at plural types of optical recording media in which the thickness of substrates of the optical recording media is different from one another.

Optical head device and optical recording and reproducing apparatus


A magnetically-loaded artificial magnetic conductor surface provides enhanced bandwidth. The structure includes in one embodiment a thumbtack structure with a spacer layer that is loaded with a barium-cobalt hexaferrite based artificial magnetic material. Specifically, the geometry consists of a ground plane covered with thinly sliced ferrite tiles that are metallized and stacked. Each tile has a metal via running through its center that is electrically connected to the plated metallized surfaces. A foam spacer layer resides above the ferrite tiles. Atop the foam spacer layer rests a capacitive surface, which can be realized as a single layer array of metal patches, a multiple layer array of overlapping patches or other planar capacitive geometry.

The present invention relates generally to high impedance surfaces. More particularly, the present invention relates to artificial magnetic conductor surfaces loaded with ferrite-based artificial magnetic materials.
A high impedance surface is a lossless, reactive surface whose equivalent surface impedance,
            Z      s        =                  E        tan                    H        tan              ,approximates an open circuit and which inhibits the flow of equivalent tangential electric surface current, thereby approximating a zero tangential magnetic field, Htan≈0. Etan and Htan are the electric and magnetic fields, respectively, tangential to the surface. High impedance surfaces have been used in various antenna applications. These applications range from corrugated horns which are specially designed to offer equal electric (E) and magnetic (H) plane half power beamwidths to traveling wave antennas in planar or cylindrical form. However, in these applications, the corrugations or troughs are made of metal where the depth of the corrugations is one quarter of a free space wavelength, λ/4, where λ is the wavelength at the frequency of interest. At high microwave frequencies, λ/4 is a small dimension, but at ultra-high frequencies (UHF, 300 MHz to 1 GHz), or even at low microwave frequencies (1-3 GHz), λ/4 can be quite large. For antenna applications in these frequency ranges, an electrically-thin (λ/100 to λ/50 thick) and physically thin high impedance surface is desired.
One example of a thin high-impedance surface is disclosed in D. Sievenpiper, "High-impedance electromagnetic surfaces," Ph.D. dissertation, UCLA electrical engineering department, filed January 1999, and in PCT Patent Application number PCT/US99/06884. FIG. 1 shows an example of such a high impedance surface 100. The high-impedance surface 100 includes a low permittivity spacer layer 104 and a capacitive frequency selective surface (FSS) 102 formed on a metal backplane 106. Metal vias 108 extend through the spacer layer 104, and connect the metal backplane to the metal patches of the FSS layer, creating what may be termed a thumbtack structure. The thickness h of the high impedance surface 100 is much less than λ/4 at resonance, and typically on the order of λ/50, as indicated in FIG. 1.
The FSS 102 of the prior art high impedance surface 100 is a periodic array of metal patches 110 which are edge coupled to form an effective sheet capacitance. This is referred to as a capacitive frequency selective surface (FSS). Each metal patch 110 defines a unit cell which extends through the thickness of the high impedance surface 100. Each patch 110 is connected to the metal backplane 106, which forms a ground plane, by means of a metal via 108, which can be plated-through holes. The periodic array of metal vias 108 has been known in the prior art as a rodded media, so these vias are sometimes referred to as rods or posts. The spacer layer 104 through which the vias 108 pass is a relatively low permittivity dielectric typical of many printed circuit board substrates. The spacer layer 104 is the region occupied by the vias 108 and the low permittivity dielectric. The spacer layer is typically 10 to 100 times thicker than the FSS layer 102. Also, the dimensions of a unit cell in the prior art high-impedance surface are much smaller than λ at the fundamental resonance. The period is typically between λ/40 and λ/12. This configuration of metal patches 110 and metal vias 108 may be referred to as a thumbtack structure.
A frequency selective surface (FSS) is a two-dimensional array of periodically arranged elements which may be etched on, or embedded within, one or multiple layers of dielectric laminates. Such elements may be either conductive dipoles, patches, loops, or even slots. As a thin periodic structure, an FSS is often referred to as a periodic surface.
Frequency selective surfaces have historically found applications in out-of-band radar cross section reduction for antennas on military airborne and naval platforms. Frequency selective surfaces are also used as dichroic subreflectors in dual-band Cassegrain reflector antenna systems. In this application, the subreflector is transparent at frequency band f1 and opaque or reflective at frequency band f2. This allows placement of a feed horn for band f1 at the focal point for the main reflector, and another feed horn operating at f2 at the Cassegrain focal point. In this manner, a significant weight and volume savings can be achieved over using two conventional reflector antennas. Such savings is critical for space-based platforms.
The prior art high-impedance surface 100 provides many advantages over corrugated metal structures. The surface is constructed with relatively inexpensive printed circuit technology and can be made much lighter than a corrugated metal waveguide, which is typically machined from a block of aluminum. In printed circuit form, the prior art high-impedance surface can be 10 to 100 times less expensive for the same frequency of operation. Furthermore, the prior art surface offers a high surface impedance for both x and y components of tangential electric field, which is not possible with a corrugated waveguide. Corrugated waveguides offer high surface impedance for one polarization of electric field only. According to the coordinate convention used herein, a surface lies in the x-y plane and the z-axis is normal or perpendicular to the surface. Further, the prior art high-impedance surface provides a substantial advantage in its height reduction over a corrugated metal waveguide, and may be less than one-tenth the thickness of an air-filled corrugated metal waveguide.
A high-impedance surface is important because it offers a boundary condition which permits wire antennas conducting electric currents to be well-matched and to radiate efficiently when the wires are placed in very close proximity to this surface (e.g., less than λ/100 away). The opposite is true if the same wire antenna is placed very close to a metal or perfect electric conductor (PEC) surface. The wire antenna/PEC surface combination will not radiate efficiently due to a very severe impedance mismatch. The radiation pattern from the antenna on a high-impedance surface is confined to the upper half space, and the performance is unaffected even if the high-impedance surface is placed on top of another metal surface. Accordingly, an electrically-thin, efficient antenna is very appealing for countless wireless devices and skin-embedded antenna applications.
Another example of a high impedance surface is disclosed in U.S. Pat. No. 6,512,494 B1, issued to Diaz, et al. on Jan. 28, 2003. This reference discloses an artificial magnetic conductor which is resonant at multiple resonance frequencies. The artificial magnetic conductor is characterized by an effective media model which includes a first layer and a second layer. Each layer has a layer tensor permittivity and a layer tensor permeability having non-zero elements on the main tensor diagonal only. U.S. Pat. No. 6,512,494 B1 is incorporated herein in its entirety by this reference. The disclosed AMC is a two-layer, periodic, magnetodielectric structure where each layer is engineered to have a specific tensor permittivity and permeability behavior with frequency. This structure has the properties of an artificial magnetic conductor over a limited frequency band or bands, whereby, near its resonant frequency, the reflection amplitude is near unity and the reflection phase at the surface lies between +/−90 degrees. This engineered material also offers suppression of transverse electric (TE) and transverse magnetic (TM) mode surface waves over a band of frequencies near where it operates as a high impedance surface.
FIG. 2 is a photograph of a prior art artificial magnetic conductor 200. The AMC 200 is embodied with a thick foam core spacer layer 204 and an array of metal patches 210 with metal vias 208 extending from some of the metal patches 210 through the spacer layer 204. The AMC 200 was developed under DARPA Contract Number F19628-99-C-0080. The size of the AMC 200 is 10 in. by 16. in by 1.26 in thick (25.4 cm×40.64 cm×3.20 cm). The weight of the AMC is 3 lbs., 2 oz. The 1.20 inch (3.05 cm) thick, low permittivity spacer layer is realized using foam. The FSS has a period of 298 mils (7.57 mm), and a sheet capacitance of 0.53 pF/sq.
FIG. 3 shows the measured reflection coefficient phase referenced to the top surface of the AMC 200 as a function of frequency. A ±90° phase bandwidth of 900 MHz to 1550 MHz is observed. Three curves are traced on the graph, each representing a different density of vias within the spacer layer (one out of every two possible vias is installed, curve AMC 1-2, one out of every four is installed, curve AMC 1-4, and one out of every 18 vias is installed, curve AMC 1-18). As expected from the effective media model described in U.S. Pat. No. 6,512,494 B1, the density of vias does not have a strong effect on the reflection coefficient phase.
Test set-ups are used to experimentally verify the existence of a surface wave bandgap in an AMC. In each case, the transmission response (S21) is measured between two Vivaldi-notch radiators that are mounted so as to excite the dominant electric field polarization for TE and TM modes on the AMC surface. For the TE set-up, the antennas are oriented horizontally. For the TM set-up, the antennas are oriented vertically. Absorber is placed around the surface-under-test to minimize the space wave coupling between the antennas. The optimal configuration—defined empirically as "that which gives us the smoothest, least-noisy response and cleanest surface wave cutoff"—is obtained by trial and error. The optimal configuration is obtained by varying the location of the antennas, the placement of the absorber, the height of absorber above the surface-under-test, the thickness of absorber, and by placing a conducting foil wall between layers of absorber.
FIG. 4 illustrates the measured S21 for both transverse electric (TE) and transverse magnetic (TM) configurations for the AMC 200 of FIG. 2. As can be seen, a sharp TM mode cutoff occurs near 950 MHz, and a gradual TE mode onset occurs near 1550 MHz. This bandgap is correlated closely to the +/−90-degree reflection phase bandwidth of the AMC.
Broadband antennas such as spirals can be mounted over the thick foam core AMC 200 of FIG. 2. FIG. 5 shows a spiral antenna on the thick foam AMC core of FIG. 2. Such antennas exhibit good impedance and gain performance over the range of frequencies where both a +/−90-degree reflection phase occurs, for normal incidence, as well as where a surface wave bandgap (where both TM and TE modes are cutoff) is found.
In most wireless communications applications, it is desirable to make the antenna ground plane as small and light weight as possible so that it may be readily integrated into physically small, light weight platforms. The relationship between the instantaneous bandwidth of an AMC such as the AMC 200 of FIG. 2 and its thickness is given by the following equation:
      BW          f      0        =      2              πμ      r                                            h                  λ          0                    .
Here, h is the thickness of the spacer layer, λ0 is the free space wavelength at resonance where a zero degree reflection is observed and μr is the magnetic permeability of the spacer layer. As can be seen from this equation, to support a wide instantaneous bandwidth BW. the AMC thickness λ0 must be relatively large or the permeability must be high μr. For example, to accommodate an octave frequency range (BW/f0=0.667), the AMC thickness must be at least 0.106 λ0, corresponding to a physical thickness of 1.4 inches (3.56 cm) at a center frequency of 900 MHz. This thickness is too large for many practical applications. As noted, the antenna ground plane should be as small and light weight as possible.
Accordingly, there is a need for an improved artificial magnetic conductor with enhanced bandwidth offering reduced size and weight.

Artificial magnetic conductor surfaces loaded with ferrite-based artificial magnetic materials

Titan Systems Corporation/Aerospace Electronic Division


A system and method for customer satisfaction survey for a customer service provided over a telephone network. A customer initiates a telephone call to a customer service number provided by a company. The company's PBX receives the call and transfers it to a computer telephony integration (CTI) server for dynamically assigning an available customer service representative to the call. During the course of a call, the CTI server monitors the call for push-tones transmitted by the caller. Receipt of a push-tone during the conversation is assumed to be an indication of the customer's satisfaction associated with the call at the time the push-tone was transmitted. The CTI server also presents questions to the customer at the end of the call but prior to hangup to receive additional feedback about the customer's satisfaction about the call. The gathered information is stored as customer satisfaction data for later analysis by an analysis computer.

In today's competitive market where one company's product and price are indistinguishable from another's, companies often attempt to gain edge over their competitors by offering better customer service and support. For instance, many companies provide toll-free phone numbers that customers can call to obtain help and/or answers to questions from a representative of the company.
Customers, however, may become dissatisfied in using such toll-free phone numbers for numerous reasons. Often, if there are not enough representatives to handle the incoming calls, a calling customer may have to wait a considerable amount of time for a representative to become available. Although the customer does not generally incur phone charges during the call, in today's fast-paced world, the customer may not have the time to wait for a representative to become available.
Customers may also go through numerous transfers to different departments or representatives before finally being connected to an appropriate representative. The customer may also at times have to wait for a call-back from the representative if the representative cannot provide an immediate answer or help the customer. This again may result in long waits and cause frustration on the part of the customer.
Even if the customer is promptly connected to an appropriate representative, the customer may still be dissatisfied if the representative lacks the skill to provide the aid requested by the customer. Furthermore, the representative may fail to be courteous and offend the customer with his or her tone of voice or manner of speech.
A customer dissatisfied for any of the above reasons may decide to have no further relations with the company and instead, start to deal with the company's competitor. Thus, it is important to promptly identify the areas of dissatisfaction and take corrective measures to enhance the quality of customer service. To achieve this, companies may decide to randomly select and record a conversation between a customer and a representative for later review by a supervisor for level of skill and courtesy. Some companies may mail survey forms or place follow-up phone calls to the customers and inquire about their satisfaction of a the service received.
The above described methods, however, gather information about a customer's satisfaction substantially after a call has been completed. Therefore, the information gathered may not accurately reflect the customer's feelings at the time of the call. Furthermore, the described manual methods of gathering and analyzing customer satisfaction information are generally inefficient, time-consuming, and unreliable.
Accordingly, there is a need for a system and method for gathering a customer's satisfaction level contemporaneously with a current call. Such a system should also provide automation for efficiently gathering and analyzing customer satisfaction information.

System and method for customer satisfaction survey and analysis for off-site customer service


An apparatus to position a quilting hoop organization relative to an individual's lap includes a base plate having telescoping first and second tubes extending from the base plate in an orthogonal relationship, with the second tube mounting positioning tubes in a manner to pivotally position the quilting hoops in a desired angulation relative to an individual's lap. The apparatus is arranged for ease of disassembly for transport and storage.

1. Field of the Invention
The field of invention relates to quilting apparatus, and more particularly pertains to a new and improved quilting hoop apparatus wherein the same is arranged to permit positioning and orientation of a quilting hoop relative to an individual's lap, while simultaneously positioning the quilting hoop in a stable relationship relative to an underlying floor support surface.
2. Description of the Prior Art
Quilting frame structure of various types have been utilized throughout the prior art wherein U.S. Pat. No. 4,658,521 indicates a frame structure including a rectilinear plurality of legs arranged with slots for positioning the legs in a spaced relationship relative to one another.
U.S. Pat. No. 4,422,251 to Hedrick sets forth a further example of quilting hoop structure.
The instant invention attempts to overcome deficiencies of the prior art by providing for a quilting hoop arranged for orienting the quilting hoop in a pivotal relationship relative to an individual's lap while mounting the quilting hoop structure firmly to an underlying support surface and in this respect, the present invention substantially fulfills this need.


A poppet valve which has a valve stem is moved up and down to open and close a valve port in an internal combustion engine of a vehicle such as an automobile. A moving coil is wound on a bobbin mounted to the valve stem, and a magnet is mounted to a yoke fixed to a cylinder head. A plurality of sensors detect working conditions of the engine to send a signal to a working condition discriminating portion of CPU. The signal is further sent to a valve timing lift pattern memory in which optimum valve timing and lift are set corresponding to the working conditions to generate an optimum valve position signal. In the meantime, an actual position of the valve is detected by a sensor on the yoke to send an actual valve position signal to a valve position detector. In a comparator, the actual valve position signal from the valve position detector is compared with the optimum valve position signal from the valve timing lift pattern memory to apply to an electric current to the moving coil to move the valve up and down so that difference between the two signals may not occur.

The present invention relates to a method of controlling an electric valve drive device which opens and closes an intake or exhaust poppet valve, and a control system therefor in an internal combustion engine.
A valve drive system in an ordinary engine mainly comprises a cam shaft, a rocker arm (or a tappet), a valve spring and a valve spring retainer, and rotation of the cam shaft driven by a crank shaft is transferred to a poppet valve via the rocker arm to make opening/closing movement.
Output performance and fuel efficiency of an engine generally depend on intake and exhaust efficiency, and the higher they are, the higher engine performance is obtained owing to smooth gas exchange in a cylinder.
However, an automobile engine has broad rotation range, so that it is difficult to improve engine performance over the whole operation range. If high speed performance is increased, low speed performance is decreased, and if low speed performance is increased, high speed performance is decreased.
To solve the problem, there is high-speed valve timing wherein lifts of intake and exhaust valves become larger to increase intake/exhaust efficiency to have larger overlapping area, while there is a small overlapping area valve timing wherein lifts become smaller to form a strong swirl at low speed where combustion is likely to be unstable.
Recently, to meet such requirements, an engine which has a valve operating mechanism of both low and high speed performance, or a variable valve timing lift mechanism which has two valve timing and lifts for low and high speeds is utilized.
However, the variable valve timing lift mechanism is basically similar to the mechanical valve operating mechanism which has the above cam shaft as drive source, and it is thus impossible to remove the performance decrease factor which such valve operating mechanism inherently has, or the performance decrease factor caused by mechanical loss and followability of a valve to a cam.
Valve timing and lift are determined by phase and profile of a cam, and it is impossible to vary them over the whole working range of the engine. There is actually no choice but to set two valve timings and lifts for low and high speed as above.
To solve the problem, as disclosed in Japanese Patent Laid-Open Pub. Nos. 10-37726 and 10-141928, it has been suggested to provide an electromagnetic valve drive device in which a valve is opened and closed by magnetic force instead of mechanical valve drive system having a cam shaft. But, in such a electromagnetic valve drive device, the valve is merely opened and closed by attractive force of an electromagnet, thereby increasing seating noise and providing low responsiveness during operation.
Furthermore, because the control area for valve timing and lift is small, it is difficult to obtain optimum valve timing and lift corresponding to any working condition of an engine, and it would be impossible to improve engine performance over the whole working range.
There is a moving iron core or piece in the valve, so that inertial mass is increased during opening and closing of the valve to decrease responsiveness and reliability at control.
To overcome the disadvantages in the foregoing electromagnetic valve drive device, the applicant suggested an electric valve drive device in which a valve is driven by an electromagnetic actuator called a voice coil motor.
A moving coil is wound around a valve stem, and inside or outside the moving coil, a magnet is fixed so that magnetic flux may be generated in a direction perpendicular to winding of the moving coil. When an electric current is applied to the moving coil, the valve is driven by axial force according to Fleming's left hand rule.
The electric valve drive device provides advantageous large control area of valve timing and lift, but there is problem how to control valve timing and lift in an optimum condition corresponding to any working condition of an engine.
Furthermore, to control the electric valve drive device depending on the working condition of the engine, it is inevitable to provide a valve position detector for detecting actual position of the valve. There are difficulties in mounting position, detecting accuracy and durability against heat.

Method of controlling an electric valve drive device and a control system therefor


The technology described herein provides a slidable, retractable, and foldable cargo floor organizer with a rotatable and extensible retention net frame and associated cargo retention net for the rear cargo floor area of a vehicle. The system additionally provides an interior cargo tray having multiple partitions. The system includes a cargo retention net frame disposed about the interior cargo tray, wherein the cargo retention net frame is extensible, and a cargo retention net, the cargo retention net being disposed about the retention net frame, and wherein the cargo retention net is extensible and extends as the cargo retention net frame extends. The system provides for the secure containment of cargo in the rear cargo floor area of a vehicle.

The vehicle cargo systems now in general use for the rear floor cargo area are used to prevent cargo items from moving around freely or sustaining damage during transit. A variety of rear floor cargo organization and retaining systems and methods have been described previously and are known in the related art. None of these systems or methods, however, is designed to solve the particular problem addressed by the technology described herein, and none is capable of being modified to do so. For example, U.S. Pat. No. 5,772,370, issued to Moore on Jun. 30, 1998, discloses a net-type cargo restraining system for motor vehicles of the type having a cargo floor with a front area, and a hinged exterior door which opens from outside the vehicle to provide access to the cargo floor. Also, for example, U.S. Pat. No. 6,439,633, issued to Nemoto on Aug. 27, 2002, discloses a luggage holding apparatus for a vehicle used in coordination with removable floor panels covering the rear cargo area of the vehicle. Neither Moore nor Nemoto disclose a system for a slidable, retractable, and foldable cargo floor organizer with a rotatable and extensible retention net frame and associated cargo retention net for the rear cargo floor area of a vehicle. Additionally, neither Moore nor Nemoto disclose a system providing multiple storage compartments. Therefore, a need still exists for such a system as the one described herein.


An improved air blast apparatus for yarn drawing machines includes a main pipe, a guide pipe, and a polygonal draft box coaxially mounted on the guide pipe. The guide pipe has a throat portion, whereas the draft box has a blast nozzle 180 degrees apart from the throat portion. Such a design and the arrangement of the angles of the draft box help interfere with the air currents inside the draft box so that the air pressure may be more evenly distributed.

1. Field of the Invention
This invention relates generally to an air blast apparatus, and more particularly to an air blast apparatus for yarn drawing machines in which the blast effects are enhanced.
2. Description of the Prior Art
FIG. 1 illustrates a conventional air blast apparatus 10 used in yarn drawing machines. It comprises a tubular guide pipe 11 which has a peripheral wall provided with a throat portion 111. A blast nozzle 12 having a blast outlet 121 extends from a front end of the throat portion 111. High pressure introduced from two ends 112 of the guide pipe 11 blows out from both side sections 122 of the blast outlet 121 and does not reach the middle section 123 of the pipe. In order that the draft blows out from the whole length of the blast outlet 121, the draft pressure has to be increased. However, there will still be high pressure at both side sections 122 and low pressure at the middle section 123.

Air blast apparatus for yarn drawing machines


A document feeder apparatus is provided for feeding documents along a document feed path. The document feeder apparatus comprises a picker mechanism for picking a number of documents from a stack of documents stored in a hopper and moving the picked documents along the document feed path. An advance mechanism includes an advance roller having a longitudinal central axis and being rotatable about its longitudinal axis. The advance roller has an outer circumferential surface which is engageable with one side of the picked document moving along the document feed path. A retard mechanism includes an endless retard belt having an outer major side surface which is engageable with the opposite side of the picked document moving along the document path. The outer major side surface of the endless retard belt and the outer circumferential surface of the advance roller cooperate to define at least a portion of the document feed path therebetween. Tension is applied to the endless retard belt such that a relatively constant pinch pressure is applied to the picked document while the picked document is moving along that portion of the document feed path between the outer major side surface of the endless retard belt and the outer circumferential surface of the advance roller.

The present invention relates to document feeding along a document feed path, and is particularly directed to a document feeder for feeding a document along a document feed path in a document processing system such as a bank check processing system.
Many different types of document feeder apparatus are known. Some known document feeder apparatus include an advance/retard mechanism which is typically either a pair of belts which are spring loaded against each other or a pair of rollers which are spring loaded against each other. During proper operation of the advance/retard mechanism, misfeeding of documents and damage to documents being fed are avoided. Due to normal wear and tear, the contact surfaces of the pair of belts or the contact surfaces of the pair of rollers become contaminated. The advance/retard mechanism may not operate properly when the contact surfaces of the belts or the contact surfaces of the rollers become contaminated. When the advance/retard mechanism is not operating properly, a fault condition such as a double document feed condition may result.


A method for performing Multivariable Matrix Spectral Factorization has been developed, which allows factorization in real time high-dimensional matrices with multivariable high-order polynomial or non-rational entries. Systems implementing the method provide improved performance and capabilities in applications reducible to multivariable matrix spectral factorization.

The spectral factorization problem was originally formulated in the scalar case by Wiener and independently Kolmogorov in connection with linear prediction theory of stationary stochastic processes. Wiener used the matrix generalization of the problem in the study of multidimensional stationary time series. In parallel, Helson and Lowdenslager introduced multivariable matrix spectral factorization in the prediction theory of vector valued stationary sequences indexed with multiple parameters. Since then spectral factorization has become an important tool in solving numerous applied problems in Control and Communication Engineering. In particular, it is used for wireless and underwater communications, radar systems, data compression, and virtually any problem with randomized models.
Since Wiener's original effort to create an efficient computable method of matrix spectral factorization (1-D MSF), dozens of papers addressed the development of appropriate algorithms.
A new effective method of matrix spectral factorization (1-D MSF) has been proposed. This method has been awarded U.S. Pat. No. 9,318,232 B2. However, the patented 1-D MSF method does not contain a generalization to the multivariate case (n-D MSF). Matrix Spectral Factorization (1-D MSF) is used to process multidimensional data indexed with 1 parameter (e.g., vector valued time series), while a Multivariable Matrix Spectral Factorization (n-D MSF) would process multidimensional data indexed with n parameters (e.g., color 2-D images, or 3-D tomographic images).

Multivariable matrix spectral factorization

New York University in Abu Dhabi Corporation


The present invention relates to a method for transmitting multiresolution audio signals via wireless devices in a radio frequency communication system wherein audio signals are decomposed into levels of resolution. The audio signal is decomposed into levels including a base signal at a base transmission rate and one or more signal details and input into a code rate selector, controlled by either party to the communication. The base signal represents the coarsest resolution or quality of the signal. Each signal detail, when added to the base signal, improves the resolution of the signal by increasing the detail and the transmission rate. An audio receiving unit transmits a request for audio transmission to the audio transmitting unit. In response to the initial request, the base signal is transmitted to the audio receiving unit. If the base signal is insufficient, the sound quality can be increased incrementally by sending further requests to transmit additional signal detail from the code rate selector. The additional signal detail is then recombined with the base signal at the audio transmitting unit to provide a higher level of sound quality to the signal. The higher quality audio signal is then transmitted to the audio receiving unit.

In current technology, a radio frequency communication system following a specific standard is governed by a maximum audio transmission rate. A typical maximum audio transmission rate is on the order of 64,000 bits per second (64 kbps) which corresponds to high fidelity audio. However, transmission of audio signals at full rate requires a significant amount of resources in terms of power and spectrum. Thus, full rate audio transmission is not cost-efficient for applications such as mobile cellular communications, but is more suited to wireline communication systems or high-power directive microwave links where these parameters are not as critical.
In addition, for mobile cellular communication systems, the predominant use is for voice communication such as conversations between parties via radiotelephones. For simple voice communication, high fidelity audio is not critical for efficient communication. The human ear is capable of discerning audio signals at much lower resolution. In these instances, audio transmission rates on the order of 3,200 bits per second (3.2 kbps) may provide sufficient audio quality for the parties to the conversation. Communication at this level results in significant conservation of power and spectrum resources for the communication system. However, there may be instances where high fidelity audio is required, for example, where a musical recording must be transmitted. The problems lies in that the audio transmission rate is determined when the audio signal is coded and the coding device typically is set to code the signal at a single predetermined rate. Thus, there exists a trade-off between conservation of power and spectrum resources at a low transmission rate and providing an acceptable audio resolution to the system user at a high transmission rate. Therefore, a system is needed to eliminate this trade-off whereby the resolution or the quality of an audio signal transmitted via radio frequency communication systems can be varied by the users to meet specific situations.

Method for transmitting multiresolution audio signals in a radio frequency communication system as determined upon request by the code-rate selector


A magazine loader including a body including a front strap, a back strap and side panels extending between the front and back straps, a hollow portion being defined between the front and back straps and side panels for receiving therein a firearms magazine, wherein the front and back straps and side panels are configured to substantially match an outer contour of a grip of a given manufacturer's weapon, and a tongue extending from an upper portion of the body with a cartridge contact surface that faces towards the hollow portion, wherein when a magazine is placed in the hollow portion the cartridge contact surface is positioned to push a cartridge into the magazine.

It is common practice to load cartridges into a firearm magazine by progressive compression of the magazine's spring. The cartridges are inserted one at a time against the ever increasing spring resistance as the magazine approaches a fully-loaded condition. If the next cartridge is simply loaded against the previously loaded cartridge, it is recognized that considerable force and manual dexterity are required.
The unaided loading of a firearm magazine is time consuming and difficult, especially when trying to push in the last few cartridges into the magazine. Moreover, loading by pressing down with one's fingers without any manual assistance can lead to misalignment of cartridges within the magazine and possible jamming of the cartridges. In order to overcome such problems, there have been many different types of manual devices that have been developed to aid in magazine loading.


A virtual machine (VM) has direct access to an I/O device having physical and virtual functions and a mailbox register, and includes a guest driver for controlling the virtual functions. The VM runs on system software that includes a physical driver for controlling the physical function (PF) and maintains VM page tables, which include an entry that references a memory space into which the mailbox register is mapped. The system software registers a callback function with the physical driver, which the physical driver invokes upon receiving a trigger for communication with the guest driver. In response, the system software alters the page tables so that access to the mailbox register causes a PF intercept, and the callback function handles the communication with the guest driver. After completion of the communication, the system software alters the page tables so that access to the mailbox register does not cause a PF intercept.

Virtualization of I/O devices poses challenges. Currently, software performs virtualization of an I/O device by interposing itself between a driver for the I/O device running in a guest operating system (OS) and the underlying hardware I/O device. When triggered by a guest memory access, the virtualization software parses I/O commands, translates the guest addresses into host physical addresses and ensures that referenced memory pages are present in memory. Additionally, the virtualization software serializes multiple I/O requests from all virtual machines into a single I/O stream to be handled by the underlying hardware, thereby sharing the underlying hardware among all of the virtual machines. However, CPU overhead is needed to implement the software virtualization of the I/O device, and such overhead reduces the throughput that the I/O device is capable of delivering.
An alternative to software virtualization is direct assignment. In direct assignment, the physical I/O device is controlled directly by a native driver in the guest OS. The result is a major improvement in performance because no software intervention is involved. However, direct assignment has a limitation in that the I/O device cannot be shared among virtual machines (VMs). The physical I/O device is assigned to only one VM.
Thus, I/O virtualization that allows sharing of I/O devices, as well as high performance of the I/O devices, is needed.
Single root I/O virtualization (SR-IOV) is an attempt to answer this need. SR-IOV provides two new functions types, physical functions, and virtual functions. Physical functions (PFs) manage the entire SR-IOV device. Virtual functions (VFs) are numerous lightweight versions of the SR-IOV device sufficient to support several VMs, thereby allowing sharing of the physical I/O device among VMs and direct access to the virtual functions by the VMs.
However, while SR-IOV devices solve the problem of sharing and high performance by allowing VMs, through guest VF drivers installed therein, to have direct access to sharable virtual functions, another difficulty emerges. With direct access (i.e., bypassing the virtualization software), the virtualization software lacks information about the state of the SR-IOV device. In addition, guest VF drivers may be exchanging messages with a host PF driver to acquire information about the capabilities of the underlying hardware, but the virtualization software is unaware about the state of these communications. The virtualization software needs information about the state of the SR-IOV device and the communications between the PF driver and the guest VF drivers to perform several functions. First, the virtualization software may need information about the state of the SR-IOV so that it can standardize the view of the SR-IOV device and its capabilities to the VMs using the device. Second, the virtualization software needs information about the SR-IOV device to perform checkpointing of a VM, which includes suspending the VM, taking a snapshot of the VM, and possibly migrating the VM to a different host. Checkpointing of a VM is complex because the state of communications between the PF and the VFs is maintained in multiple layers of software, including the guest VF driver, the host PF driver, and the hardware. Complete emulation of the SR-IOV device could handle the complexity of checkpointing, but complete emulation would defeat the direct access feature between the VF driver and the SR-IOV device. Third, the virtualization software needs information about the SR-IOV device to handle an error condition that the SR-IOV may experience so that the virtualization software can inform other parts of that software of the error condition.
It would be an advantage to employ SR-IOV devices in a way that allows the virtualization software to keep informed of the state of the SR-IOV device so that the virtualization software can carry out functions of providing a uniform view of an I/O device, of checkpointing the VM, and of notifying other parts of the virtualization software of error conditions of the SR-IOV device.

Techniques for virtualizing PF-VF mailbox communication in SR-IOV devices


A stiffness mechanism for a boot having a shell with a flexibility slot and a cuff pivotally secured to the shell includes a buckle assembly selectively engageable with a portion of the shell for selectively securing the cuff to the shell. A blocking assembly is selectively disposable within the flexibility slot for selectively increasing the stiffness of the shell. A lever assembly is pivotally disposed between the buckle assembly and the blocking assembly. When the lever assembly is moved into a first position, the cuff is secured to the shell and a portion of the blocking assembly is disposed within the flexibility slot to increase the stiffness of the shell. When the lever assembly is moved into a second position, the cuff is pivotal with respect to the shell and the blocking assembly is at least partially disengaged from the flexibility slot to increase the flexibility of the shell.

Certain sporting boots require the use of a hard shell to provide support to the user during use. For instance, ski boots include a stiff exterior shell or boot portion that encloses a soft interior sleeve for receiving the foot and ankle. A semi-rigid cuff is secured to the shell for adjustably surrounding the calf of the user during use.
The cuff is also often pivotally secured to the shell so that the cuff may pivot with respect to the boot shell to provide flexibility in the ski boot during "walk mode." In addition, the shell will also often have one or more relief cuts or splits that allow the boot shell to flex at the relief cuts in walk mode. For instance, a boot may have a U-shaped relief cut at the rear of the shell that allows the upper portion of the shell to flex or distort when the lower leg bends forward and engages the front portion of the shell (causing the cuff to engage and press against the rear portion of the shell). The upper ends of the U-shaped relief cut can distort or bend inwardly to accommodate this movement.
However, it is typically desired to have the boot portion and cuff fixed relative to one another in a stiffened position in "ski mode" to provide increased support to the user for an enhanced skiing experience. There are numerous prior art devices that selectively secure the cuff to the shell in "ski mode" and allow the cuff to pivot with respect to the boot shell in "walk mode." However, these devices fail to close off the one or more relief cuts, splits, or slots in the shell that allow the boot shell to flex.
Other prior art devices close off a portion of the relief cuts in the shell so that the shell can flex only partially during "ski mode." More specifically, the device may include a blocking mechanism that is disposable within the relief cut to engage the shell when it flexes, thereby restricting the shell from further flexing during "ski mode" and increasing its stiffness. However, these prior art devices do not completely prevent the shell from flexing during "ski mode."
Thus, it is desired to have a ski/walk mechanism that selectively secures the cuff to the shell in "ski mode," and that allows the cuff to pivot with respect to the boot shell in "walk mode," and that further selectively closes off the one or more relief cuts in the shell in "ski mode" to maximize the stiffness of the shell.


Trenches may be formed in layers on a semiconductor substrate for defining electrical components for an electronic device, such as an amplifier. A polishing step may be performed after formation of the trenches and deposition of other layer(s) to define regions for resistors, capacitors, or other elements in a metal layer on a semiconductor substrate. The polishing step may create discontinuities in metal layers on the semiconductor substrate that define electrically isolated regions corresponding to the resistors, capacitor, and other components of the electronic device.

As electronic devices have increased in operational functionality and complexity, the cost and difficulties with manufacturing the electronic devices has also increased. In particular, the processing of semiconductor wafers to form components for the electronic devices has become increasingly complex. For example, to shrink the size of an electronic device, the components on the semiconductor wafer must be smaller and the components on the semiconductor wafer must be packed closer together to increase the density of the components. In addition to manufacturing challenges for making smaller components, the components are typically more complex and require many processing steps to form the components on the semiconductor substrate. Of the processing steps, patterning steps are often the most expensive to perform because each patterning step may require a different mask. Masks are pieces of glass that contain patterns that are copied repeatedly onto each semiconductor substrate to form the components. Masks have a limited lifetime and are expensive to create.
As one example, amplifiers are used in many electronic devices. In particular, cellular phones and audio players use amplifiers to produce signals for driving speakers in the devices or headphones connected to the devices. Amplifiers may include resistor and capacitor components that are difficult to form on a semiconductor substrate. Conventionally, manufacturing resistors, capacitors, and other components for an amplifier on the semiconductor substrate requires patterning using two, three, or more masks. Each mask adds complexity and cost to the manufacturing process.
Further, one or more metal layers of the resistor, capacitor, or other components are patterned with a dry or wet etch process. The wet or dry etch of the metal layer may create undesirable effects due to the difficulty of etching metal layers. FIG. 1 shows certain problems encountered during a conventional dry etch process of metal layers. A structure 100 on a semiconductor substrate (not shown) may include a nitride layer 102, a dielectric layer 104, and a conducting layer 106. A hard mask layer 108 may be deposited and patterned with a mask to form opening 110, which will be transferred to the conducting layer 106 through a dry etch. During the dry etch process, ions from a plasma bombard the conducting layer 106 and cause physical removal of atoms of the conducting layer 106. This patterning may form a portion of a resistor or capacitor for an amplifier in the conducting layer 106. During the dry etch process, undesirable effects may occur that negatively impact the structure 100. For example, the opening 110 may not transfer directly into the conducting layer 106. Instead, an angled sidewall 112 may change the shape of the feature of opening 110 in the conducting layer 106. As another example, material etched from the conducting layer 106 may redeposit material 114 onto the dielectric layer 104 during the plasma etch operation. The conducting materials redeposited 114 onto the dielectric layer 104 reduce the dielectric strength of the dielectric layer 104 and reduce the reliability of components formed with the dielectric layer 104. As a further example, the dry etch may undercut a void 116 in the dielectric layer 104. Each of these examples illustrate that the dry etch may not transfer the pattern of opening 110 into the underlying structure 100 with high fidelity. The problems may be further enhanced when the conducting layer 106 is a material that is difficult to etch, such as such as tantalum, tantalum nitride, Titanium, Titanium nitride, Silicon Chromium.
Shortcomings mentioned here are only representative and are included simply to highlight that a need exists for improved electrical components, particularly for amplifiers in consumer-level devices. Embodiments described here address certain shortcomings but not necessarily each and every one described here or known in the art.

Formation of electrical components on a semiconductor substrate by polishing to isolate the components


The present invention refers to exopolysaccharide molecules, conditioned media or compositions comprising said molecules or media. Moreover, the present invention refers to use of said exopolysaccharide molecules, conditioned media or compositions as prebiotic, preferably to boost immune system.

The consumption of food products and supplements named probiotics, i.e. containing live microbial cells, to potentially prevent or treat specific diseases, is constantly gaining popularity.
A number of Lactobacillus species, but also some other have been proposed as, and are used as, probiotic strains—live microorganisms as food supplement in order to benefit health.
Strains of Lactobacillus paracasei are Gram-positive, non-spore-forming bacteria that are common inhabitants of the human intestinal tract. Specific strains of L. paracasei are found naturally in a number of fermented food products, and they have traditionally been used in the production of fermented milks and cheeses.
More recently, specific strains of L. paracasei have been used in probiotic dietary supplements, including the strain L. paracasei DG (commercially known as L. casei DG®, Enterolactis®). A range of health-promoting properties has been assigned to L. paracasei DG including the improvement of ulcerative colitis and treatment of small intestinal bacterial overgrowth and a number of mechanisms have been proposed for the probiotic effect.
One of the most studied mechanisms relates to the ability of probiotic bacteria to antagonize pathogenic organisms by either excretion of antimicrobial agents or the displacement of pathogenic organisms through the competitive occupancy of adhesion sites. In addition, there are a number of reports referring to the health benefits result from stimulation of the immune system by components presented at the surface of probiotic strains.
Several studies have demonstrated that the polysaccharides present at the surface of the bacteria, referred to as either capsule or as exopolysaccharides (EPSs), can play a role in both the displacement of pathogenic organisms and the stimulation of the immune system.
In this context, the present invention refers to exopolysaccharide molecules and their use as prebiotics and/or probiotics, in particular to boost immune system.


A moisture-absorbent padding used in combination with and for lining a food product container, such as a pizza box, includes parallelepiped strips each having a cavity therein and a moisture-absorbent material within the cavity. The strips further have vertically oriented monolithic orifices disposed within a front wall of each strip. The orifices open into the cavity and absorb moisture released from a food product stored within the container. The apparatus may also include a laterally flanging parallelepiped reservoir downwardly and angularly disposed on each side of each orifice which collects moisture seeping away from the moisture-absorbent material. An adhesive material on the rear wall attaches each strip to an inside edge of an outer wall of the food container.

1. Technical Field
This invention relates to padding accessories and, more particularly, to a moisture-absorbent padding for use in combination with a cardboard pizza box for preventing pizza from becoming soggy prior to human consumption.
2. Prior Art
In the field of padding hot carry-out food, such as pizza, a common goal has been to protect the food by maintaining a desirable high food-temperature and retaining the desirable characteristics and quality of the particular food, such as, in the case of pizza, a crispy crust. One particular problem is controlling the release of water vapor (steam) from the package without losing heat from the food. If the steam is not released from the package, it will generally condense within the package, eventually soaking the food item, and resulting in a loss of both product crispness (e.g., the pizza crust will become soggy) and product quality.
For the most part, the prior art relies on a combination of vents, formed within the walls of the package to release any steam from the food, and tabs which raise the food above a bottom surface of the package. Although these prior art methods and structures may be effective in removing steam from the package, they fail to maintain adequate food temperature. Too much convection within the package draws too much heat from the food, resulting in a cold, albeit crispy food product. Further, without adequate support a product, such as a pizza, may collapse, particularly when the crust becomes soggy.
Accordingly, a need remains for a moisture and steam absorbing article for pizza pie containers and the like in order to overcome the above-noted shortcomings. The present invention satisfies such a need by providing an apparatus that is convenient and easy to use, is durable yet lightweight in design, is versatile in its applications, and provides users with a simple and effective means of keeping a pizza crispy and fresh while in transport.
The present invention satisfies such a need by providing a hat insert that is convenient and easy to use, is durable yet lightweight in design, is versatile in its applications, and which provides a flexible strip having an absorbent deodorized inner layer and including a bilaterally symmetrical trapezoidal upper portion and mirror image lower portion attached together with a connection band which folds along a center longitudinal axis to cover a hat inner band.

Moisture-absorbant padding for use in combination with a pizza box and associated method


A bucket holding and tipping device with an adjustably movable cinching band on which are engaged one or more foot plates. On each plate, the band passes through slots in the plates and the plates are adapted to receive in pressing relationship the bottom of a human foot. Each plate also has a handle opening in the plate.

Plastic buckets, and in particular the slightly tapered five gallon buckets sold at home improvement and construction supply stores, are commonly used for tipping and pouring a wide range of substances. In landscaping, for example, such buckets may be used for pouring out materials such as gravel, drain rock, mulch, and dirt. In the building trades buckets are often used to dispense construction materials. Buckets are frequently used for cleaning purposes, and excess cleaning fluids that remain in a bucket may require pouring off.
A bucket generally has a single handle located on a wire bail that swings from side to side on the bucket. When a bucket is filled or partially filled with materials, however, it can become heavy and difficult to control while tipping and pouring. Too much or too little material may be dispensed from the bucket, or the bucket may slip from the hand or hands of the user, potentially causing injury.
Many construction materials require mixing prior to use. These include mortar, grout, drywall joint compound, self-leveling compounds, and many other materials. The example bucket above is commonly used by tradespeople (sometimes also in the three gallon size) as a mixing vessel. Materials are typically mixed with a paddle bit attached to an electric drill.
However, mixing viscous substances in a bucket can be hazardous as the bucket tends to want to spin in the direction the mixing bit is turning A person may try to hold the bucket in place between his or her legs while mixing, or alternatively, set a foot on the rim of the bucket to stabilize it. Neither method provides a secure grip on the bucket and can permit the bucket to spin, and even to tip over, during mixing. This can lead to a waste of material and can potentially cause injury to the person.
There are a number of foot plate or foot pedal devices and foot stand devices known for use in holding cylindrical containers such as buckets and for securing a bucket in place during mixing. Nearly all of these devices are intended to secure a bucket during the mixing process only. See for example U.S. Pat. No. 7,651,060 to Roth. A bucket may be placed on, or in, the device, the device is engaged to secure the bucket, a substance is mixed in the bucket, and the bucket is removed from the device for use in the work area. Other such devices are typically bulky and must be carried to the work area separately from the mixing bucket.
There is one known device that provides an additional handle for buckets, disclosed in U.S. Pat. No. 7,399,017 to Lasseigne. It appears to be unnecessarily bulky and heavy, overly complex and expensive to manufacture. It also appears to be designed solely as a handle for the bottom of a bucket, and suggests no other locational or positional alternatives.
No known auxiliary handhold devices for cylindrical containers are also constructed for accepting a person's foot or feet to secure the bucket in place for mixing viscous materials, and none of the bucket hold-down devices provide handle functions for tipping, pouring, or carrying a bucket. There are no known handles that can be positioned wherever a users wants—at the bottom, top, or middle of a bucket.


According to one aspect of the invention, a storage compartment having an illuminating device mounted therein and a tray having a lens mounted thereon. The tray is movable within the storage compartment between a forward position and a rear position. The illuminating device may provide light to both the interior of the storage compartment and the tray depending upon the position of the tray.

1. Field of the Invention
This invention relates to a storage compartment having an opening for receiving objects, and a movable tray with a lens mounted thereon. More particularly, the invention relates to a storage compartment having an illuminating device for illuminating the interior of the tray when the tray's lens is positioned adjacent the illuminating device, and illuminating the interior of the storage compartment when the tray is positioned away from the illuminating device.
2. Description of the Prior Art
Storage compartments having an illuminating device for illuminating accessories such as a tray or a cup holder are known and disclosed in U.S. Pat. No. 6,419,379 to Hulse. Hulse uses a single bulb in combination with a waveguide to route light to the interior of a storage compartment. U.S. Pat. No. 6,193,399 to Hulse discloses an optical waveguide for illuminating the interior of a cup holder. The waveguide is disposed at the bottom of a cup holder and has an input device for connecting with the light source. U.S. Pat. No. 6,896,387 to Renfro discloses a system for illuminating a cup holder by having a clear acrylic disk seated at the bottom of a cup holder, and an LED lamp seated within the acrylic disk. However, it remains desirable to have a storage compartment having a device that can illuminate both the interior of the compartment and the compartment's accessory, depending upon the accessory's position within the storage compartment.

Storage compartment with an illuminated tray

Toyota Motor Engineering & Manufacturing North America, Inc.


The present invention provides a device enabling the collective pitch of the blades of the main rotor of a single-engined rotorcraft to be reduced automatically in the event of an engine failure. The device comprises an actuator which increases the collective pitch of the blades above a predefined threshold, and which decreases the collective pitch below the predefined threshold. The actuator is arranged on a bell crank of the mixing unit of the rotorcraft.

In general, it is known that a single-engined rotorcraft possesses measuring instruments that provide the pilot on a continuous basis with values for the main rotor speed and for the engine speed.
The information relating to the main rotor speed is essential for the safety of the rotorcraft. Indeed, a main rotor speed too great would lead to an increase in centrifugal force on the blades, running the catastrophic risk of a blade attachment failing. A main rotor speed too small would lead to a loss of lift. Similarly, the engine speed needs to be monitored in order to remain within the bounds specified by the manufacturer of the rotorcraft, with any change in this engine speed also changing the main rotor speed.
Consequently, engine failure leads to a drop in the main rotor speed which can rapidly lead to a loss of lift for the rotorcraft. The pilot must therefore react immediately, and the only solution available to the pilot being that of reducing the collective pitch of the blades in order to change over to auto-rotation.
Auto-rotation is a technique that makes it possible with a main rotor rotating without drive from the engine, nevertheless to obtain lift that is capable of maintaining the rotorcraft in stabilized downward flight at an acceptable rate of descent. Auto-rotation thus corresponds to safety flight in the event of an engine failure. In order to ensure that the main rotor is put into auto-rotation conditions, the pilot must act immediately at the time of engine failure to reduce the collective pitch of the blades of the main rotor.
Once the collective pitch has been reduced, the pilot merely has to allow the rotorcraft to descend. The relative wind then engages the main rotor in an upward direction, thus enabling the rotor to stabilize on an auto-rotation speed.
In the event of a failure of the engine installation, it can thus readily be understood that it is essential to reduce the pitch of the blades as quickly as possible in order to retain an acceptable main rotor speed.
Nevertheless, starting from hovering flight, pitch reduction needs to be implemented very carefully in order to avoid too great an initial drop in the main rotor speed.
Document FR 2 601 326 discloses a device for switching automatically to auto-rotation flight conditions as soon as a failure appears in the engine installation. That device acts on the flight controls via an automatic pilot system.
Nevertheless, it solves the problem in part only, since some rotorcrafts do not posses an automatic pilot.

Device for providing assistance to the pilot of a rotorcraft in the event of engine failure