A method and apparatus for forming laminate composite structures. At least two laminae, each containing electrically conductive reinforcing fibers, are placed upon each other in contacting relationship to form a generally layered structure. The layered structure may be subjected to heat to conductively transfer heat through the layered structure and thereby improve the surface contact between the two laminae. The layered structure is volumetrically heated by inductively transferring energy to the electrically conductive reinforcing fibers. The heated, layered structure is consolidated, such as by applying pressure and reducing the temperature of the layered structure. The consolidated structure is then quenched by rapidly cooling the consolidated structure in a directionally controlled manner about a midplane thereof.

1. Field of the Invention
The present invention relates generally to the formation of composite structures and, more particularly, to the formation of substantially void-free laminate structures using inductive energy.
2. State of the Art
Composite articles are well known to provide advantages in diverse applications. In some applications, the advantages of composite articles over metal, ceramic or other materials include weight reduction and the ability to integrate several otherwise individual parts into a single structure. Composite articles may conventionally include a reinforcement material in a polymer-based resin, also known as the matrix material, such as thermoplastic or thermoset resin. The reinforcement materials may include, for example, chopped or continuous fibers disposed either randomly or in ordered fashion within the polymer matrix material. Composite materials are conventionally formed by configuring the reinforced matrix material into a desired form or structure, which may include heating the article to place the matrix material in a moldable condition followed by resolidification in the case of a thermoplastic, and curing of the matrix material in the case of thermoset resins.
Conventionally, composite structures are often formed as laminates, meaning that laminae, or multiple lamina, are layered on top of each other and bonded together by heating, thereby effecting melting in thermoplastics and effecting cross-linking between the multiple layers for thermoset resins. Additionally, a consolidation process is conventionally carried out on laminate structures to increase adhesion and reduce voids between the laminae. Such consolidation is conventionally carried out by processes such as vacuum debulk or through use of an autoclave.
One limitation associated with manufacturing composite articles or structures is the rate at which such articles may be processed, especially for composite articles exhibiting large cross-sectional areas. For example, existing techniques such as autoclave, pultrusion and double belt press techniques are limited at the rate by which thermal equilibrium can be achieved within the material during processing.
Conventionally, heating of composite articles has been carried out through surface heating techniques. However, the thicker the composite structure, the more difficult and time consuming it becomes to achieve the proper temperatures at or near the center of the structure. In order to reduce the process or cycle times of producing a laminate composite structure, the surface temperature may be increased in order to more quickly transfer thermal energy to the center of the composite structure. Referring to FIG. 1, an exemplary graph 100 shows the need to increase surface temperature of a composite structure in order to increase the throughput, or the amount of material processed in a given amount of time, in a conventional surface heating process. For example, the first plot 102 indicates that in order to maintain an exit temperature of 480° F. for a composite structure having a thermoplastic matrix, the surface temperature of the composite structure during processing must be increased approximately 1000° F. in order to realize a corresponding increase in the rate of throughput by approximately 19 feet/second (ft/sec). Similarly, as seen in the second plot 104, to maintain an exit temperature of 625° F. throughout the composite structure, an increase in surface temperature of approximately 1200° F. is required to increase the throughput by approximately 19 ft/sec.
However, the allowable surface temperature of the composite laminate structure is limited by its degradation temperature, which, in turn, limits the throughput or production rate. Thus, in using conventional surface heating techniques, the tradeoffs for improving production times include an increase in both capital costs and labor (i.e., through implementation of parallel production lines) and/or the production of a potentially degraded and inferior product.
In an attempt to improve production times, inductive heating techniques have been implemented in the production of composite structures. Induction heating techniques conventionally take advantage of the inductive transfer of energy from an induction coil to a conductive member either positioned adjacent a surface of the composite structure or disposed within the composite structure, such as between individual laminae or in the matrix material of an individual lamina.
For example, U.S. Pat. No. 5,229,562 issued to Burnett et al. discloses inductively heating a conductive member, such as a platen or a mandrel, which is positioned against a surface of the composite structure. However, such a method presents problems similar to those discussed above since the use of platens or mandrels is simply another means of surface heating the composite structure.
Another inductive heating technique includes placing a conductive member, such as a susceptor or a metal insert, into the composite and transferring energy through the insert and into the body of the composite. Such a technique, which may generally be referred to herein as volumetric heating, serves to bring the composite structure to thermal equilibrium much more efficiently. While volumetric heating brings the composite structure to thermal equilibrium much more quickly than surface heating, the use of metal inserts or susceptors to accomplish such may serve to mechanically weaken the resulting structure.
Another inductive heating technique involves transferring inductive energy to electrically conductive reinforcing fibers placed within the matrix material of a composite structure. For example, U.S. Pat. No. 4,871,412 issued to Felix et al., the disclosure of which is incorporated by reference herein, teaches the formation of local spot welds and seam welds for lap joints between two composite structures by inductively transferring energy to carbon fibers disposed within the two structures.
U.S. Pat. No. 5,357,085 issued to Sturman, Jr., the disclosure of which is incorporated by reference herein, teaches the heating of a polymer matrix composite strand by passing the strand through a helical guide tube adjacent an inductive coil to transfer energy into carbon fibers of the composite strand.
U.S. Pat. No. 5,338,497 issued to Murray et al., the disclosure of which is incorporated by reference herein, teaches forming a thick composite structure by placing the composite material into a mold and inductively transferring energy into conductive elements, such as metal whiskers, disposed in the matrix material while the composite material is in the mold.
However, while teaching volumetric heating of a composite structure, the above-referenced processes fail to address the use of volumetric heating in the high-volume production of laminate structures while retaining laminate quality, including the prevention of internal voids or warping. While conventional consolidation techniques may be used to reduce voids, i.e., through the use of an autoclave or by subjecting the structure to vacuum debulk, such techniques are time consuming and also require consumable or disposable waste materials. Such waste materials might include, for example, release films, bagging materials or nitrogen based volatiles used during pressurization.
In view of the shortcomings in the art, it would be advantageous to provide an apparatus and a method for forming laminated composite structures which allow for volumetric heating and prevent the subsequent growth of voids while also increasing throughput rates. It would be further advantageous to provide an apparatus and method which allow for continuous production of a laminate composite structure without the need for consumable waste materials conventionally used during consolidation.

Apparatus and method for induction lamination of electrically conductive fiber-reinforced composite materials


An ideal diode circuit is described which uses an NMOS transistor as a low-loss ideal diode. The control circuit for the transistor is referenced to the anode voltage and not to ground, so the control circuitry may be low voltage circuitry, even if the input voltage is very high, referenced to earth ground. A capacitor is clamped to about 10-20 V, referenced to the anode voltage. The clamped voltage powers a differential amplifier for the detecting if the anode voltage is greater than the cathode voltage. The capacitor is charged to the clamped voltage during normal operation of the ideal diode by controlling the conductivity of a second transistor coupled between the cathode and the capacitor, enabling the circuit to be used with a wide range of frequencies and voltages. All voltages applied to the differential amplifier are equal to or less than the clamped voltage.

Although the ideal diode of the present invention may be used in any application requiring a diode, the invention is particularly beneficial in circuits that rectify relatively high voltages and currents, such as in a power application for rectifying an AC voltage.
Many applications require the conversion of AC power to DC power, such as shown in FIG. 1. This can be done in many ways, but the most basic implementations use one or more rectifying diodes, such as in a full-wave bridge circuit. Independent of the AC frequency or topology (half-wave, full-wave, single-phase, or multi-phase), a diode-based rectifier will always include a voltage drop equal to the forward voltage of the diodes at the operating load current. Associated with this voltage drop is a power dissipation equal to the voltage drop multiplied by the diode current.
An ideal diode circuit automatically switches a low-loss switch, such as a MOSFET, when it is detected that the anode terminal is at a voltage higher than the cathode terminal. Comparators and other circuitry are used in the control circuit. The control circuit may be powered by the voltage applied to the ideal diode. Typically, the control circuit is referenced to ground, so the components in the control circuit must be able to operate with the full anode-to-ground voltage. When the voltage to be rectified is a relatively high voltage (e.g., 120 VAC), the control circuitry needs to be fabricated using special techniques to handle the high voltage without breakdown. This increases the size and cost of the control circuitry.
NMOS transistors are frequently used as the low-loss switch since their conductivity is typically better than that of PMOS transistors. Since the source of the NMOS transistor is coupled to the anode terminal, the control circuitry requires a voltage-boosting charge pump, referenced to earth ground, to generate a gate voltage higher than the anode voltage. The charge pump generally runs continuously to maintain the boosted voltage needed to drive the NMOS transistor. This continuous running of the charge pump consumes power. This boosted voltage also requires the control circuitry to handle a voltage higher than the anode voltage without breakdown.
It is also known to eliminate the earth ground reference from the boost circuit, but the boost circuit can only run when the ideal diode is off. Therefore, the ideal diode must be periodically forced off to generate the boost voltage.
What is needed is an ideal diode circuit that uses low-voltage control circuitry (e.g., up to 20 V), even when the voltage to be rectified may be a high voltage (e.g., greater than 120 VAC). What is also needed is an ideal diode circuit that can generate a boosted voltage for controlling an NMOS transistor without interfering with the normal ideal diode operation. Such an ideal diode circuit can then be operated accurately in AC applications and with high voltages to be rectified.

This patent is subject to a terminal disclaimer.

Analog Devices International Unlimited Company


Automated techniques for storing data in a data storage environment. Techniques are provided for determining storage locations for data in a heterogeneous storage environment based upon storage policies configured for the storage environment. The data is stored in storage locations that enable efficient data access while optimizing the use of available storage resources with minimum human intervention.

The present invention relates generally to the field of data storage and management, and more particularly to techniques for determining storage locations for data in a storage environment based upon storage policies configured for the storage environment.
Heterogeneous and complex storage environments comprising storage systems and devices with different cost, capacity, bandwidth, and other performance characteristics are rapidly replacing conventional homogeneous data storage environments. Due to their heterogeneous nature, managing storage of data in such environments is a difficult and complex task. An important information management function in such heterogeneous data storage environments is to determine where to store the data among the various available storage devices in a manner that reduces costs associated with the data storage while providing efficient data access.
In several conventional data storage environments, the decision where to store the data is generally manually determined by a user (e.g., a system administrator) of the data storage environment. The user may make the decision based upon data usage patterns and upon characteristics of the storage devices available in the storage environment for storing the data. Accordingly, in such environments, the system administrator has to gather frequency and data usage information, data access and performance requirements, and frequency of access information from users or consumers of the data. The administrator also has to determine characteristics (e.g., cost, capacity, other performance characteristics) of storage devices available for storing the data. The administrator then typically makes an educated guess as to where the data is to be stored. While the manual approach described above may be feasible in simple homogeneous storage environments supporting a small number of data consumers, such an approach is impractical for today's large and heterogeneous storage environments.
Presently, several conventional data management systems are available that automate part of the data storage decision making process. For example, automated data backup applications are available that perform hierarchical storage management (HSM) to move data from online to off-line storage (or primary to secondary backup media). However, conventional data management systems do not presently offer the flexibility, control, and automation desired by system administrators for managing large heterogeneous storage environments comprising a large number of data consumers, servers, and hosts.
In light of the above, there is a need for automated techniques that allow data storage administrators to efficiently manage distributed data and storage resources with minimum intervention in a manner the facilitates efficient data access while optimizing the use of available storage resources.

Techniques for storing data based upon storage policies


An inflatable packaging box to protect an item during storage and shipment, including a plurality of sidewalls, and a chamber formed within the plurality of sidewalls adapted to receive the item. An opening through at least one of the plurality of sidewalls is included, through which the chamber is accessible. A plurality of films are each secured to one of the plurality of sidewalls. Each of the plurality of films forming one of a series of elongated sections which form the chamber in the space between the series of elongated sections. Each of the series of elongated sections are inflatable to conform to the item's shape.

Protective packaging assemblies are often used when an object or article to be packaged requires protection from physical shock or other hazards, such as vibration, weather, or abrasion. For example, when shipping an object that is relatively fragile it is often desirable to package the object inside a box to protect the object from physical damage that may occur during loading, transit, and unloading. Shipped articles can come in all sizes and shapes. These articles can be fragile or hardy (i.e., the article is considered non-fragile). To add additional protection, protective packaging material is often placed within the box.
There are numerous types and forms of protective packaging material for this purpose including paper or plastic dunnage and air-cushioning or foam-cushioning structures. In general, the packaging material is intended to control the movement of the object within the box and/or provide a cushioning layer between the object and the box in order to soften or absorb the effects of a physical impact to the box. However, all of the packaging materials mentioned before can cause waste disposal and recycling issues.
In order to be effective, the packaging material typically must engage enough of the object to hold it substantially in place and engage the areas of the object likely to bear the physical impact. However, concern about not having enough packaging material, often causes users to compensate by using a great deal more packaging material than necessary. Essentially, this extra packaging material is being wasted and shipped. Alternatively, a user may not use or place enough of the packaging material in the box or, more specifically, position the packaging material in the proper areas to provide for effective protection of the object during transit. Also, in many cases, the packaging material itself might move around during transit and, thus, create protection issues. Separate packaging material, such as structural cardboard shell and foam or air cushioning material packing around the object make it difficult to automate the object shipping process.
In the process of shipping an article from one location to another, the article is typically placed in a container along with the protective packaging material to fill the voids about the article and to cushion the article during the shipping process. One common protective packaging material is comprised of a plurality of plastic foam, peanut shaped members which are commonly known as "Styrofoam peanuts."
However, while Styrofoam peanuts have been widely accepted in the packaging industry, they are not without disadvantages. For example, the light weight and flowability of the Styrofoam peanuts results in heavier objects gravitating through the peanuts to the bottom of the container where the object can be damaged. Also, while the flowability of the Styrofoam peanuts facilitates the introduction of the peanuts in the container, the receiver of the package is left with having to deal with the peanuts upon removal of the article from the container in the form of having to clean up the mess left by the peanuts which are easily scattered upon removal of the article from the container.


The present invention provides a dielectric thin film capacitor element in which leak current may be suppressed from increasing over time while energizing at high temperature and which has excellent insulating quality and reliability and a manufacturing method thereof. The dielectric thin film capacitor element is constructed by forming a lower electrode, a dielectric thin film and an upper electrode one after another on a substrate, wherein the dielectric thin film capacitor element is characterized in that the dielectric thin film is made of an oxide material composed of at least titanium and strontium and containing erbium.

1. Field of the Invention
The present invention relates to a dielectric thin film capacitor element used for electronic parts such as an IC capacitor, and a nonvolatile memory device and to a method of manufacturing the same.
2. Description of Related Art
Hitherto, Ta.sub.2 O.sub.5 (tantalum pentoxide), SiO.sub.2 (silicon dioxide) and SiN (silicon nitride) have been mainly used as a dielectric material of a dielectric thin film capacitor for an IC typified by a signal accumulating capacitor of a DRAM and a capacitor for a microwave device of a MMIC (Microwave Monolithic Integrated Circuit). However, with the recent miniaturization and high-integration of electronic parts along the progress of the semiconductor technology, an extra-thin dielectric thin film or three-dimensional dielectric thin film has come to be fabricated in order to reduce capacitor area. For this reason, a process for fabricating semiconductor devices has become more and more complicated and the micro-processing technology has come close to its limit, causing a problem in yield, reliability and the like. Then, a dielectric thin film having a higher dielectric constant as compared to that of the conventional dielectric thin film has become necessary. Presently, a research on an oxide high dielectric thin film made of SrTiO.sub.3 (strontium titanate) or (Ba, Sr)TiO.sub.3 (barium strontium titanate) having a higher dielectric constant as compared to SiO.sub.2 and SiN described above is being actively conducted.
However, the dielectric thin film capacitor element using the conventional oxide high dielectric thin film such as SrTiO.sub.3 and (Ba, Sr)TiO.sub.3 described above has had a big problem in its reliability. That is, no high dielectric thin film capacitor element which provides practical enough characteristics has been realized yet in a high temperature energizing test, which is a usual reliability test for electronic parts, in which a certain voltage is applied to a capacitor while holding the capacitor at a certain temperature. For example, in a high temperature energizing test of bias application of 10 V to the capacitor while holding the capacitor at 100.degree. C., leak current increases by three to four digits in about 10 hours, causing a problem of degradation of resistance of the capacitor such that it cannot maintain the insulation required as the capacitor.
The degradation of the resistance of the capacitor is considered to be caused by the following reason. In the oxide high dielectric thin film such as SrTiO.sub.3 and (Ba, Sr)TiO.sub.3, a lattice defect of oxygen (oxygen vacancy) occurs within the thin film during its growth. Because the oxygen vacancy is electrified to +bivalent in a capacitor element composed of the dielectric thin film containing the oxygen vacancy, the oxygen vacancy moves to the cathode side when the capacitor element is heated and voltage is applied between electrodes thereof during the high temperature energizing test. Then, the oxygen vacancy which has moved to the cathode side cannot move to the cathode due to a potential barrier of the cathode and SrTiO.sub.3 or (Ba, Sr)TiO.sub.3 and it increases at the boundary of the cathode and the dielectric thin film. At this time, electrons are injected from the cathode side to electrically compensate for it. Further although oxygen vacancy is introduced newly from the anode side, the electrons are generated as a carrier at this time. Due to these phenomena, the conductivity increases as time passes by and leak current increases in the dielectric thin film as a whole.
It is conceivable to implement an oxygen annealing treatment or oxygen plasma treatment in which heat treatment is implemented within an oxygen atmosphere after forming the film in order to compensate for the oxygen vacancy and to prevent the capacitor from degrading. However, even if such treatment is implemented, it is difficult to reduce the oxygen vacancy after forming the dielectric thin film because oxygen is not stably incorporated into a dielectric crystal lattice in terms of thermal equilibrium.
As a prior art technology, an experimental example in which a characteristic time tch until the occurrence of a dielectric breakdown could be prolonged, when energized in high temperature, by doping La.sub.2 O.sub.3 to a bulk ceramic sintered body of BaTiO.sub.3 is described in J. B. MacCHESNEY et al., J. Am. Ceram. Soc., 46(1963)197. Specifically, it is reported that while the time until the occurrence of the dielectric breakdown was 2 hours in one to which no La.sub.2 O.sub.3 has been doped, it increased up to 1000 hours or more in one to which 0.50 mol % of La.sub.2 O.sub.3 has been doped.
Further, R. Waser et al., J.Am.Ceram.Soc., 73(1990) 1645 describes an experimental case in which the increase of leak current was suppressed, when energized in high temperature, by doping 0.3 mol % of La to a SrTiO.sub.3 bulk ceramic sintered body.
Further, Japanese Unexamined Patent Publication JP-A 6-326250 (1994)(TI) describes a case in which (Ba, Sr)TiO.sub.3 to which 0.25 mol % or more of La, Er and the like has been doped is used as a high dielectric material.
Although all of the prior art technologies described above use the bulk ceramic sintered body to which La is doped as a dielectric material, it is difficult to contain a desired content of La in the process for forming this film. Further, although Japanese Unexamined Patent Publication JP-A 6-326250 (1994) describes about the use of Er, of which content is set at 0.25 mol % or more, the time until the occurrence of a dielectric breakdown is short when the content is 0.25 mol % or more.


A fluid delivery system for delivering a metered dose of fluid from a supply tank (28) to a downstream chamber or vessel (10), comprises a pump apparatus (20) comprising a pump plunger (32) which is operable to perform a pumping stroke under the control of an electromagnetic actuator (36), including a solenoid (36a), to effect delivery of the fluid and a control unit (24) for supplying an input signal (58) to the solenoid (36a) to initiate a current flow to the solenoid (36a) and thereby initiate movement of the pump plunger (32). An electronic device (54) provides an output signal to indicate that movement of the pump plunger has stopped at the end of the pumping stroke, and a timer determines a time difference between the input signal (58) being supplied to the solenoid (36a) and the output signal being output by the electronic device (54). A processor (26) compares the time difference with a predetermined time difference and determines, as a result of the comparison, whether or not the pump plunger (32) has performed a valid pumping stroke in which an intended volume of fluid is displaced.

Internal combustion engines emit undesirable pollutants in their exhaust stream. One such pollutant is nitrogen oxides, comprising nitrogen monoxide and nitrogen dioxide (hereinafter referred to simply as "NOx"). NOx is generated from automobile engines such as diesel engines, and other combustion devices. Accordingly, exhaust system devices are coupled to the engine to limit and/or remove the pollutants from the exhaust system. Technologies have been and continue to be developed to attenuate these emissions.
NOx may be cleaned from exhaust gases of internal combustion engines through the use of catalysis. In addition to removing NOx, other catalysts may be employed to also remove unburned hydrocarbons (HC) and carbon monoxide (CO). When the engine is operated with a lean air/fuel ratio, the catalyst is efficient at removing the HCs and COs because of the extra oxygen in the exhaust gas. However, the extra oxygen tends to inhibit the removal of NOx.
In the case of exhaust gas from gasoline engines, NOx is usually removed by using so-called three-way catalysts. Also, in the case of large, stationary combustion apparatus, such as internal combustion engines for cogenerators, metal oxide catalysts such as V2O5 are used, and ammonia is introduced into the exhaust gas stream, whereby nitrogen oxides in the exhaust gas are catalytically and selectively reduced.
Conventional Selective Catalytic Reduction (SCR) of NOx involves injection of a typically aqueous urea solution or reductant into the exhaust system ahead of the SCR catalyst. Common reductants include aqueous urea in conjunction with selective catalytic reduction, and perhaps hydrocarbon diesel fuel, for the supplemental heat necessary to initiate particulate trap regeneration. As used herein the term "urea" is meant to encompass urea in all of its commercial forms, including those containing: ammelide; ammeline; ammonium carbonate; ammonium bicarbonate; ammonium carbamate; ammonium cyanate; ammonium salts of inorganic acids, including sulfuric acid and phosphoric acid; ammonium salts of organic acids, including formic and acetic acid; biuret; cyanuric acid; isocyanic acid; melamine and tricyanourea.
The reductant dosing system is required to accurately meter the reductant into the exhaust system, while being robust in service and responsive to the engine or after treatment control system. Accordingly, most prior art dosing systems have been designed for delivery of reductant in a two fluid system, namely the reductant and a supply of pressurized air. Such systems make use of a simple low pressure metering pump for delivering the reductant into a mixing chamber where it co-mingles with pressurized air from an onboard source. This mixture is conducted through a pipe to the remote dosing location in the exhaust where it exits through a simple atomizing nozzle into the exhaust stream. A typical air atomizing pressure for this type of system might be 2 bar. By way of example, EP 1 149 991 describes a two fluid system of the aforementioned type.
Since urea is not essential to the functioning of the engine, it is possible to operate the engine even when the supply of urea is low or has been depleted altogether. However, such a condition is unacceptable, not least because the engine then no longer complies with statutory regulations for emissions levels. It is therefore known to provide the urea tank with a urea level sensor (not shown) so that imminent exhaustion of the supply can be forewarned. U.S. Pat. No. 6,063,350, for example, describes a reagent dosing system in which such a level sensor is used for this purpose.
Aqueous urea is a common reagent in such systems, but the characteristics of the fluid are problematic in certain respects. For example, aqueous urea can form hard salt crystals which clog mechanisms and disrupt regular operation. For this reason, fluid level sensors of the mechanical type, which employ a float on a pivoting arm connected to a variable resistance coil, are unsuited for use in a urea supply tank. Typically, therefore, a more expensive urea level sensor is employed that is immune from clogging.
It is one object of the invention to provide a system for use in delivering reagent in an SCR exhaust gas cleaning system of an internal combustion engine in which the requirement for a separate reagent level sensor is removed altogether.


A method of forming a leadframe package, a leadframe package formed according to the method, and a system incorporating the leadframe package. The leadframe package includes: a metallization layer comprising a paddle portion and a contact portion including contact leads; a die mounted onto the paddle portion; wirebonds connected between the die and respective ones of the contact leads; an overmold encapsulating the die, the paddle portion, the contact leads and the wirebonds; and a stiffening element encapsulated in the overmold and unconnected to electrical pathways within the leadframe package.

According to well known prior art integrated circuit (IC) packaging methodologies, microelectronic dice are singulated and mounted using epoxy or other conventional means onto respective die pads or attach paddles of a leadframe strip. FIG. 1 shows a cross sectional view and a top view of a conventional leadframe package 100. Leadframe package 100 includes a die 110 mounted using die attach epoxy (or other means) 112 onto a die attach paddle 114. The leadframe 100 includes wire bonds 116 that are bonded between die 110 and peripheral leads or contacts 118. An overmold 120 encapsulates the die 110, epoxy 112, paddle 114, contacts 118, and wirebonds 116 as shown, leaving the bottom of contacts 118 exposed for joining with a motherboard.
Disadvantageously, as the length and width of the leadframe packages increases, such as for example, in the case of multi-silicon module packages, that is, in the case of a microelectronic package having a plurality of microelectronic components such as, for example, transistors, capacitors and memory devices, disposed horizontally on the package substrate, the reliability of solder joints between the motherboard and the leadframe becomes a problem. The length and width of a leadframe package may increase for a number of reasons. For example, increasing the number of microelectronic components to integrate added functionality to the leadframe package could increase a size of the package. In addition, an overall footprint of any number of microelectronic components to be integrated into the package could increase by virtue of functionality added to those components. One of the reasons for an adulteration of solder joint reliability is leadframe warping that occurs as the leadframe package dimensions increase. The warpage is typically a result of either (1) a mismatch between the coefficients of thermal expansion of the mold compound encapsulating the package components and the base metal, usually copper, onto which the leadframe package is built; (2) a mismatch between the coefficients of thermal expansion of the leadframe package substrate (for example, silicon) attached to the base metal; or (3) a mismatch between the coefficients of thermal expansion of the overmolded microelectronic device with respect to the underlying motherboard. With respect to point (1) above, when the mold material is provided onto the die, epoxy, paddle, contacts and wirebonds, it is thereafter allowed to cure, typically shrinking at a different rate than the base metal for the leadframe package, in this way bringing about a warpage of the resulting leadframe package. With respect to points (2) and (3) above, since the overmold, package substrate, base metal and motherboard material are made from different materials, they will react differently to the heat generated by the die. The resulting thermal stresses can create a warpage of the leadframe package. A warpage of the leadframe package can ultimately affect the reliability of solder joints joining the contacts of the leadframe package to the underlying motherboard. In particular, when the leadframe package is warped, it has poor coplanarity before being surface mounted onto a motherboard. The result can be poor solder joint formation or even incomplete solder joint formation with the motherboard causing electrical opens, since some joints will be taller while others will be shorter, causing inconsistent loading on joints.
The prior art fails to provide a method of improving solder joint reliability between a leadframe package and the underlying motherboard.

Microelectronic package having a stiffening element and method of making same


A supporting appliance for animals having a weak back includes a harness for encircling the animal's shoulder, a brace that extends the length of the animal's back and a girth that encircles the animal's body. The brace provides support for the animal's back so that the animal may undertake normal movements otherwise difficult or prevented due to insufficient back strength. Alternately, the brace may be oriented on the halter and girth so that when the appliance is secured to the animal, the brace lies along and provides support for the animal's stomach. A second brace may also be attached to the halter and girth such that when the appliance is secured to the animal, a combination of support to the animal's back and stomach is provided. The appliance may include a plurality of girths or a single girth in the form of a unitary band that extends essentially the length of the animal's back.

1. Field of the Invention
The invention relates generally to orthopedic devices for animals, and more particularly to an appliance to be secured to an animal to provide back support to remedy a weak or ailing back.
2. Description of the Related Art
As animals age they undergo weakening of their bodies, and in particular their backs. It is not uncommon, for example, in a long bodied breed of dog, for them to suffer from a herniated disk, leading to partial or even complete paralysis. Older beagles for instance may suffer from herniated disks because their legs are short, and in proportion their backs tend to be very long, making them assume a swayback posture leading generally to inflamed disks. As inflammation continues the disks tend to deteriorate. In such cases, appliances in the form of a two-wheel carriage have been used to support the animal's hind quarter so that the animal's movement may be facilitated by using only the animal's front legs. Other symptoms of weakening and deteriorating bodies are manifest in a sagging stomach and weakening of leg muscles.
In distinct contrast for humans, not only is medication available to alleviate such problems, but orthopedic braces, in many forms, are available to facilitate walking, sitting and other normal body activities. For animals, on the other hand, if medication fails to remedy their failing condition, the animal exists in a painful and diminished capacity, has expensive and and often times futile surgery or is mercifully put to sleep. To assist such animals, it would be useful and helpful to provide a supporting appliance for reinforcing an animal's back which would be lightweight, easy to apply, comfortable to the animal, easy to store and inexpensive. The supporting appliance should not interfere with the animal's motion, but, to the extent possible, restore the animal's ability to move in a more normal fashion.


A chuck and an article are configured such that the article is releasably secured in the chuck. One of the chuck and article is provided with a crest and the other with a trough. When the article is secured to the chuck, the crest enters the trough so as help prevent slippage of one with respect to the other. The chuck may include a receiver having a tapered bore, a collet having a complementarily tapered outer surface, and a nut configured to be threadingly secured to a forward end of the receiver; the article may be a shank, such as a tool shank. An inner surface of the collet may be provided with a crest which is configured to fit into a trough formed on the shank. In a secured position, the shank is accommodated in the bore of the collect with the crest of the collet at least partially occupying the trough of the shank, thereby preventing movement of the shank relative to the collet, which itself is accommodated in the bore of the receiver.

Chucks, which removably secure articles, such as tools or work-pieces, to machine tools, are well known in the art. Such chucks may employ flexible collets, which may expand or contract radially, to releasably grip the article in the chuck.
It has been known that occasionally, the gripped article may slide axially relative to the chuck, especially when relatively large axial cutting forces act on the article. Such axial sliding is undesirable, and may adversely affect the quality of the work-piece, the life of the tool, or both.
It is an object of the present disclosure to present an improved chuck. This object is attained with the subject matter in accordance with the claims.

Chuck and article having mating features to prevent axial slippage


An electricity metering method and apparatus is provided for determining the phase of first waveform relative to a harmonically distorted, second waveform having cycles temporally distinguished by an occurrence of an amplitude that is neither zero amplitude nor a maximum amplitude of said waveform.

The present invention relates to a method and apparatus for determining the relative phase of two waveforms and, more particularly, to an electricity metering method and apparatus for determining the phase of distorted voltage and current waveforms.
Electric power is typically generated at a remote, central generating facility and transported to the consumer over a distribution system. To reduce power transportation losses, a step-up, subtransmission transformer is used to increase the voltage and reduce the current for transmission over a transmission line. The actual transmission line voltage usually depends on the distance between the subtransmission transformers and the consumers of the electricity but is commonly in the range of 2–35 kilo-volts ("kV"). Distribution substation transformers and distribution transformers of an electric utility's secondary power distribution system reduce the voltage from the transmission line level to a distribution voltage for delivery and use by industrial, commercial, and residential customers. In the United States, for example, electric power is typically delivered to the consumer as a alternating current (AC) voltage ranging from 120 volts ("V") to 660 V, depending upon the use. As generated, the fundamental AC voltage and current approximate 60 Hertz ("Hz") sine waves over time.
The consumption of power by individual consumers and the performance of the distribution system are monitored by power meters. Power meters are used to monitor a number of electrical parameters related to power distribution and use, including the active power, the time rate of transferring or transforming energy, and the apparent power, the product of the root mean square (RMS) voltage and current. In addition, the reactive power, the product of the RMS voltage and the quadrature component of the current, and the power factor or quality factor, the ratio of active power to apparent power, are commonly monitored.
Power meters may also be used to measure the phase angle between the current and voltage waveforms. The phase angle expresses the temporal relationship of a cycle distinguishing feature of a first waveform, commonly an amplitude peak or a zero crossing, to the position of a corresponding feature in another waveform. As generated, the voltage and current waveforms are in phase and simultaneously reach zero, maximum, and minimum amplitudes. If the load is purely resistive, the voltage and current remain in phase. However, if the load is capacitive, the phase distinguishing feature of the current waveform will precede that of the voltage waveform and the phase angle is designated as leading. On the other hand, an inductive load produces a lagging phase angle with the phase distinguishing feature of the voltage waveform preceding that of the current waveform. The reactive power consumed by capacitive and inductive loads causes power losses in the transmission system and reduces the overall efficiency of the power distribution system. Phase angle measurement permits billing the consumer for reactive power losses and analysis of the nature of the load so that power conditioning equipment can be added to the system to reduce the reactive power losses.
Inductive, capacitive, and resistive loads have impedances that are independent of voltage and at any single frequency the impedances of these loads are linear. While an inductive or capacitive load will cause the relative phase angle of the voltage and current to change, the sinusoidal voltage and current waveforms are not distorted when an AC voltage is applied to an inductive, capacitive, or resistive load. Sinusoidal waveforms have definite zero crossings and amplitude peaks and, typically, either a zero crossing or an amplitude peak is selected as the distinguishing feature to temporally mark the cycles of a waveform when determining the phase angle or phase.
Referring to FIG. 1C, on the other hand, power electronic loads; including variable speed drives, rectifiers, inverters, and arc furnaces; draw current 60 in short abrupt pulses 62 rather than in a smooth sinusoidal manner and are characterized as non-linear. When a non-linear load is connected to a sinusoidal voltage, the current flow is not proportional to the instantaneous voltage and is not sinusoidal. The non-linearity of power electronic loads produce harmonics of the fundamental voltage sine wave. In a power distribution system, the expected frequency of the voltage or current, e.g., 50 Hz, 60 Hz, or 400 Hz, is conventionally referred to as the "fundamental" frequency, regardless of the actual spectral amplitude peak. Integer multiples of this fundamental frequency are usually referred to as harmonic frequencies or harmonics. Referring to FIGS. 1A and 1B, when a sine wave of the fundamental frequency 20 is combined with a plurality of harmonics 22, 24, 26, 28 the instantaneous amplitude of the resulting waveform 30 is a sum incorporating the instantaneous amplitude of the fundamental waveform and the corresponding instantaneous amplitudes of the harmonic waveforms. Determining the phase of a waveform relative to an amplitude peak or a zero crossing of a harmonically distorted waveform 30 is problematic because the contributions of higher frequency harmonics commonly produces a plurality of contemporaneous amplitude peaks 32, particularly in the vicinities of the expected amplitude peaks or zero crossings of the fundamental waveform. As a result of the dithering of the amplitude, the distorted wave commonly includes a plurality of contemporaneous zero crossings 34 and amplitude peaks 32. Extensive filtering to remove harmonic frequencies from the reference waveform or other computationally intensive signal processing, such as interpolation, is required to consistently distinguish a zero crossing or amplitude peak for a succession of cycles of a harmonically distorted waveform.
What is desired, therefore, is a method and apparatus for accurate and consistent determination of the phase angle relative to a harmonically distorted waveform.

Method and apparatus for phase determination


A method and apparatus for the repair of damaged piles and a repaired pile assembly, are included herein, wherein the method comprises providing a pile comprising a first pile side configured to define a first channel, and a second pile side configured to define a second channel. The pile has at least one damaged section. The method also includes providing at least two bent plates; attaching a first bent plate to the pile to fit within the first channel; and attaching a second bent plate to the pile to fit within the second channel. The bent plates overlap the damaged section. At least one cover plate is attached to at least one of: the pile, or the first and second bent plates, to form at least one compartment. Each compartment is then at least partially filled with a grout; and the grout is cured or allowed to cure.

1. Field of the Invention
The present invention relates to the field of piles used in forming various structures, including a device and method for repairing damaged metal piles.
2. Description of Related Art
Piles of concrete, timber, steel or composite materials are an integral structural part of marine structures such as bridges, docks, piers, wharfs and the like. Piles, which are driven or jetted into the ground to some determined depth, support a structure above the water's surface. A disadvantage associated with metal or steel piles is that portions of the piles are susceptible to corrosion and/or degradation due at least in part to being located in a water environment, exposure to corrosive and/or salty air, impact from boats and other water vessels, and exposure to chemicals in the water, among other things. Even though steel piles are typically waterproofed prior to their installation, over a period of time, the waterproofing is usually not durable or protective enough to prevent the steel from corroding. Most of the damage to the piles tends to occur at the water line due to the wave action at that location. This wave action tends to be aggravated by the tides that are prevalent at many pile installations, where at high tide, water covers a greater height of the pile, while at low tide, a greater length of the pile is exposed to the air. Therefore, the piles undergo drying and wetting cycles that tend to contribute to further corrosion, thus weakening the piles at their mid sections.
While various encasement, wrapping and replacement techniques have emerged for the repair of the inevitable damage to steel piles, these techniques have some shortcomings. Encasement and wrapping may be suitable if the damage has not seriously compromised the structural integrity of the piles. However, for more serious damage, these practices are not particularly desirable as the structural strength of the repaired pile remains impaired. To repair more serious damage, a section of the pile may have to be replaced, or the pile may have to be replaced in its entirety. Furthermore, conventional replacement techniques tend to be costly, time and labor intensive, and complex.
U.S. Pat. No. 6,773,206 of DENSO™ North American Corporation describes the use of cylindrical fiber-form jackets, such as fiberglass or nylon, that are placed over the whole length of the pile to be repaired, or over the damage at the pile's tidal zone. The fiber-form jackets may be filled with concrete. The same patent also describes that the ROCKWATER Corporation in Farmingdale N.Y. discloses a similar system for damaged pile sections surrounded by fiberglass and nylon reinforced pile jackets filled with concrete. U.S. Pat. No. 6,773,206 also discloses a jacket having two halves that have been bolted together around a damaged pile. However, the fiberglass and nylon materials used in these jackets tend to be quite costly. Further, the jackets are hard to install, particularly underwater, making for an extremely cumbersome installation process, which makes such installation time consuming and labor intensive. Adding to these problems is that great care must be taken when handling fiberglass jackets, as they are quite delicate. Further, these jackets do not serve to significantly improve the structural strength of the repaired pile. In fact, the jackets tend to deteriorate over time, and may even separate and become detached from the pile, providing no compressive strength to the damaged pile at all. Additionally, these types of jackets, which are usually cylindrical, take up a lot of space. This in undesirable where repairs are being made under mud piles, as the large footprint created by the jacket may not fit within the confines of the area authorized by environmental permits for this type of installation. It is also known in the art, including U.S. Pat. No. 6,773,206, that a plastic jacket may be used with alternative filled jackets which suffer from many of the same issues associated with the fiber-form jackets.
U.S. Pat. No. 6,561,736 describes a coupler having steel sheathing members clamped against an H-pile in a particular configuration. An embodiment designed for H-piles further includes two channel members placed in each channel of the H-pile, and a locking bar member located along the longitudinal edge of the H-pile.
U.S. Pat. No. 5,813,800 describes an H-pile coupler having flat steel plates bolted to the flat sides of the H-pile, and a replacement H-pile section fastened to the flat steel plate reinforcement members. This patent teaches removal of the damaged pile section prior to installation of the coupler and replacement H-pile.
Even in view of the prior art designs, there remains a longstanding need in the art for alternative devices and methods for repairing piles which protect and structurally reinforce a pile.

Method and apparatus for repairing piles


Systems and methods for providing a power signal to one or more implantable devices include a number of dynamic range amplifiers each having a multiplicity of output drivers. Each of the output drivers is configured to generate an output signal. The systems and methods further include control circuitry configured to select at least one of the amplifiers to provide a number of output signals used to generate the power signal that is to be provided to the one or more implantable devices. The control circuitry is further configured to disable the output drivers corresponding to a remaining number of amplifiers. A matching circuit is configured to generate the power signal based on the output signals provided by the at least one selected amplifier. The systems and methods further include means to transmit the power signal to the one or more implantable devices.

Radio-frequency (RF) powered implantable stimulators and battery powered implantable stimulators are described in the art. See, for instance, U.S. Pat. No. 5,193,539 ("Implantable Microstimulator); U.S. Pat. No. 5,193,540 ("Structure and Method of Manufacture of an Implantable Microstimulator"); U.S. Pat. No. 5,312,439 ("Implantable Device Having an Electrolytic Storage Electrode"); U.S. Pat. No. 6,185,452 ("Battery-Powered Patient Implantable Device"); U.S. Pat. Nos. 6,164,284 and 6,208,894 (both titled "System of Implantable Device for Monitoring and/or Affecting Body Parameters"). Each of these patents is incorporated herein by reference in its respective entirety.
Implantable stimulators may be used to treat a variety of medical disorders. For example, to overcome sensorineural hearing loss, numerous cochlear implant systems, also referred to as implantable cochlear stimulator (ICS) systems, have been developed. These devices seek to bypass the hair cells in the cochlea, which are essential to hearing but which may not functioning properly, by presenting electrical stimulation directly to the auditory nerve fibers. This leads to the perception of sound in the brain and at least partial restoration of hearing function. To facilitate direct stimulation of the auditory nerve fibers, an array of electrodes may be implanted in the cochlea. A sound processor processes an incoming sound and translates it into electrical stimulation pulses applied by these electrodes to directly stimulate the auditory nerve.
A typical implantable stimulator is intended to remain permanently in the body of a patient once it is implanted. For this reason, many stimulation systems include one or more external devices configured to communicate with and support the stimulator or other device that is implanted within the patient. For example, some exemplary cochlear implant systems include a behind-the-ear (BTE) signal processor that may be positioned behind the ear and used to support an implanted stimulator.
The external portion of many stimulation systems includes a radio frequency (RF) power amplifier that is configured to provide power to the portion of the stimulation system that is implanted within the patient. The external portion will be specifically designed to meet the power requirements of the implanted device.

Systems and methods for providing power to one or more implantable devices


An illumination system capable of varying the light emission intensity of illumination light while maintaining the color balance of the illumination light is provided. An additive process illumination system obtaining a specific color light by mixing a plurality of color lights, the illumination system may include a plurality of light sources each emitting a different color light; a lighting period varying means for varying the lighting period of each light source; a light emission intensity varying means for varying the light emission intensity of each light source; and a control means for controlling the lighting period varying means and the light emission intensity varying means to control the light emission amount of each light source.

1. Field of the Invention
The present invention relates to an additive process illumination system obtaining a specific color light by mixing a plurality of color lights, and a liquid crystal display using such an illumination system.
2. Description of the Related Art
In recent years, flat panel displays as typified by liquid crystal TVs and plasma display panels (PDPs) have become a trend, and among them, most of mobile displays are liquid crystal displays, and precise color reproducibility is desired in the mobile displays. Moreover, as backlights for liquid crystal panels, CCFLs (Cold Cathode Fluorescent Lamps) using fluorescent tubes are mainstream; however, mercury-free light sources are environmentally desired, so light emitting diodes (LEDs) and the like hold promise as light sources replacing CCFLs.
Further, illumination systems using LEDs and the like have become commercially practical recently.
In such illumination systems using LEDs in related arts, the drive currents of the LEDs are controlled by pulse width modulation (PWM) to adjust their light emission intensities (for example, refer to Japanese Unexamined Patent Application Publication No. 2005-310996).
FIG. 20 shows the circuitry of an illumination system using LEDs controlled by PWM in a related art. An illumination system 101 includes a main power source 110, constant current power sources 110R, 110G and 110B, a light source section 111 including a red LED 111R, a green LED 111G and a blue LED 111B each of which includes a plurality of serially connected LEDs, PWM drivers 113R, 113G and 113B, switches 114R, 114G and 114B, a light receiving section 115 including a red light receiving section 115R, a green light receiving section 115G and a blue light receiving section 115B, a light receiving signal processing section 116, an A/D conversion circuit 117 and a CPU (Central Processing Unit) 118. In the illumination system 101, by power supplied from the main power source 110, constant currents I101, I102 and I103 flow from the constant current power sources 110R, 110G and 110B to the red LED 111R, the green LED 111G and the blue LED 111B, respectively, and a red light, a green light and a blue light are emitted. Moreover, such color lights are received in the light receiving section 115, and the light receiving signal processing section 116 and the A/D conversion circuit 117 perform a predetermined signal process on light receiving signals of the color lights, and on the basis of the light receiving signals, control signals are supplied from the CPU 118 to the PWM drivers 113R, 113G and 113B. Then, the on/off states of the switches 114R, 114G and 114B are controlled by the PWM drivers 113R, 113G and 113B, respectively, so the lighting periods of the red LED 111R, the green LED 111G and the blue LED 111B are individually controlled.

Illumination system and liquid crystal display


Disclosed in the present specification is a circuit board. The circuit board includes a first reference plane and a second reference plane, wherein the second reference plane includes a defected ground structure. The circuit board also includes a signal trace coupled to a signal via, wherein the signal trace is disposed above the first reference plane. The circuit board additionally includes a spiral inductor positioned adjacent to the defected ground structure, wherein the spiral inductor is coupled to the signal via.

Transmission of electrical signals in a circuit board can result in energy loss. The energy loss is usually dependent on the frequency of the transmission. For example, signal loss will generally be higher at higher frequencies. The signal loss variation across the frequency range of a signal can make it more difficult for signal receivers to recover the transmitted data. Accordingly, signal equalization techniques are used to equalize the frequency dependent loss. These techniques use active circuit designs that consume power. In some cases, a redriver or repeater is needed for extra equalization, requiring additional power.


This invention relates to methods and apparatus for medical imaging of parts of a patient in which imaging data acquisition is gated by a combination of electrocardiogram (ECG) and peripheral pulse (PPU) signals from the patient. The methods of the invention include obtaining ECG signals from a patient in a medical imaging apparatus, obtaining PPU signals from the patient, providing one or more synchronization signals in dependence on both the ECG signals and the PPU signals, wherein the synchronization signals indicate occurrences of pre-determined phases of the cyclic movements of the heart only if the PPU signals also indicate that the determined heart phase is physiologically possible, and controlling the medical imaging apparatus in dependence on the synchronization signals to collect imaging data synchronized with cyclic movements of the heart from the patient in the examination zone and to reconstruct a medical image of a part of the patient from the collected imaging data. The medical imaging apparatus of the invention includes such units in addition to the imaging units as are necessary from the practice of the methods of the invention. This invention is preferably applied to magnetic resonance imaging and to computed tomographic x-ray imaging.

1. Field of the Invention
The present invention relates to methods and systems for medical imaging of parts of a patient in which acquisition of data by a medical imaging apparatus for image reconstruction is gated by a combination of electrocardiogram (ECG) and peripheral pulse (PPU) signals from the patient.
2. Description of the Related Art
Many organs and regions of the body of a patient are affected by cardiac and respiratory motions, including, for example, not only the heart, the lungs, and vessels throughout the body, but also abdominal organs, especially upper abdominal organs, and intracranial structures. For the medical imaging of such affected organs, it is often useful, or even necessary, to take these motions into account. On the one hand, in the case of those imaging modalities, such as a conventional x-ray imaging, in which a single image is acquired in a short exposure (for example, a few milliseconds (msec) or less), it is often useful for images to be acquired at known and pre-determined phases of cardiac or respiratory motions.
However, on the other hand, in the case of those imaging modalities which reconstruct a recognizable image from imaging data acquired over a period of time (for example, 100 msec. or more), it is often necessary to take body motion into account in order to avoid motion artifacts that degrade reconstructed images and render them less useful clinically. Currently, important modalities of this nature include magnetic resonance (MR) imaging, computer tomographic (CT) x-ray imaging, and nuclear imaging of particles emitted by radioactive tracers administered to a patient. For many cardiac, vascular, neurologic, and other imaging examinations using such modalities, synchronization of imaging data collection sequences to the intrinsic motion of the heart is crucial to obtain high-quality images without motion artifacts.
For cardiac synchronization of medical imaging data collection, triggering data collection by features recognized in the electrocardiogram (ECG) signal or in the peripheral pulse (PPU) signal from nearly any artery can be utilized. PPU signals, in comparison to ECG signals, are always delayed with respect to the QRS complex of the ECG signal (signifying the onset of ventricular systole), and have a temporal frequency spectrum with significantly lower frequency components. The variable delay can be up to 100-200 msec. or more. Therefore, triggering with ECG signals is generally preferred to achieve triggering that is temporally more precisely defined in time and to enable data collection during early ventricular systole.
However, important medical imaging modalities often introduce noise and distortions into ECG signals measured from a patient during imaging examinations. These noise and distortions are due to various kinds of electromagnetic interference inherently generated during examination by such modalities. In the case of CT and nuclear imaging, electrical interference may be induced in the patient or in affixed ECG leads, and therefore, into resulting ECG signals, either directly from the imaging apparatus itself or secondarily by radiation used in the imaging.
In the case of MR imaging, switched magnetic field gradients, RF pulses, and hydrodynamic flows of blood containing charged ions in the strong static magnetic field present in an MR apparatus induce voltage gradients in a patient that in turn introduce noise and distortions into ECG signals. Since blood flow effects are enhanced during systole, when the blood flows in the aorta and other vessels are increased, introduced ECG artifacts are maximum during ventricular systole. Such artifacts hamper R-wave detection and, thus, successful synchronization of imaging data collection.
For example, FIG. 2A illustrates two ECG signals from a healthy volunteer. ECG 80 is recorded in an MR apparatus but without the presence of the static main magnetic field. ECG 81 is recorded in the MR apparatus in the presence of a static field of, for example, 1.5 Tesla (T). Second ECG 81, recorded in the presence of the static magnetic field, contains several additional signal peaks compared to first ECG 80, which can lead to erroneous interpretations of the ECG, for example, being recognized as non-physiological, false R-waves.
A method and apparatus that attempts to improve ECG triggering is known from U.S. Pat. No. 5,526,813. In this known method, erroneous determination of ECG features is reduced by filtering and signal processing prior to using the signal for triggering imaging data collection. However, a drawback of this known method is that the filtering and signal processing of the ECG data can be complicated and unreliable, and as a result erroneous triggering of imaging data acquisition may still occur even though the ECG signals have been filtered and processed. Another method and apparatus that also attempts to improve ECG triggering is known from International Application no. PCT/IB98/01062. According to the latter known method, information from a vector ECG (VCG) signal is used to improve recognition of ECG signal features compared to their recognition in a scalar ECG. However, measurement of a vector electrocardiogram signal is also subject to inherent noise and distortions generated by the imaging modalities, and its analysis can also be complex, difficult, and unreliable.
What is needed, therefore, are simple and reliable methods and apparatus for accurately and reliably triggering data acquisition for medical image reconstruction at fixed times with respect to the cardiac cycle.
Citation of a reference herein, or throughout this specification, is not to construed as an admission that such reference is prior art to the Applicants"" invention of the invention subsequently claimed.
The objects of the present invention are to provide methods and apparatus which overcome the above identified problems in, and satisfy the needs of, the current medical imaging art.
As used herein, it is to be understood that a xe2x80x9cmedical imaging modalityxe2x80x9d is any imaging modality that acquires imaging data by a process that can be disturbed by body motions, and, therefore, that advantageously takes heart motions into account when imaging organs that are directly or indirectly affected by such heart motions. This invention is most advantageously applied to those imaging modalities the practice of which generates noise and distortions of electrocardiogram (ECG) signals measured from a patient during imaging. Preferably, this invention is applied to magnetic resonance (MR) imaging, or to computer tomographic (CT) x-ray imaging, or to nuclear medicine imaging.
Additionally, as used herein, it is to be understood that xe2x80x9cECG signalsxe2x80x9d means any representation of the electrical activity of the heart. It includes conventional scalar representations where the time courses of single voltages measured between established positions on the patient are displayed. In these representations, the QRS complex has its well-known form, e.g., as schematically represented by signal 80 in FIG. 2A. It also includes vector electrocardiogram (VCG) representations, where the time course of the net electrical polarization vector of the heart is displayed in various projections. In these representations, the QRS complex is seen as a loop elongated along one direction. Finally, it is to be understood that xe2x80x9cPPU signalxe2x80x9d means any representation of the pulsatile flow of blood in an artery. It can be non-invasively measured, for example, by an oximeter, or invasively measured, for example, by arterial pressure, or by other means.
Generally, the objects of this invention are achieved by medical imaging methods according to which information from both ECG signals and from PPU signals are considered together in order to generate reliable synchronization signals for triggering imaging data collection in a medical imaging apparatus. The synchronization signals represent occurrences of pre-determined phases of cardiac motion so that the imaging data collection can be synchronized with the actual, physiologic, cyclic movements of the heart and with resulting blood flows. These objects are also achieved by medical imaging apparatus that, in addition to its conventional imaging means, includes further functional units necessary to practice the methods of medical imaging methods of this invention, such units as, for example, an ECG unit, and PPU unit and a synchronization unit.
Although, this invention is described herein primarily in its preferred embodiment directed to MR imaging and utilizing scalar ECG signal representations, it will be understood that this invention is not so limited. For example, it is equally applicable use of VCG signals, to CT imaging gated and to other imaging modalities. It is intended that these other embodiments apparent to one of skill in the art from the following drawing and description are also covered by the appended claims.
In detail, the objects of this invention are achieved by the following embodiments. In a first embodiment, the general methods of the invention include obtaining ECG signals representing the electrocardiogram of a patient placed in an examination zone of a medical imaging apparatus which collects medical imaging data for reconstruction of a medical image, obtaining PPU signals representing occurrences of peripheral pulses in the patient, providing one or more synchronization signals representing occurrences of one or more pre-determined phases of the cyclic movements of the heart, wherein the synchronization signals are provided in dependence on both the ECG signals and on the PPU signals, and controlling the medical imaging apparatus in dependence on the one or more synchronization signals in order to collect imaging data synchronized with cyclic movements of the heart from a part of the patient in the examination zone and to reconstruct a medical image of a part of the patient from the collected imaging data with reduced or absent motion artifacts.
In various aspects of the first embodiment, the part of the patient imaged includes cardiac structures, or intracranial structures, or vascular structures; the medical imaging apparatus is a magnetic resonance apparatus or a computed tomography x-ray apparatus; and the ECG signals include scalar ECG signals or vector ECG signals. In a further aspect, the synchronization signals are provided only if the PPU signals indicate that the pre-determined cardiac phases are physiologically possible. In this aspect, the general methods include determining, first, PPU-derived information from the PPU signals, wherein the PPU-derived information indicates time intervals within which the predetermined cardiac phases are physiologically more probable or less probable, and recognizing, second, the pre-determined cardiac phases in the ECG signal, wherein the recognizing is responsive to the probability or improbability of the pre-determined cardiac phases indicated by the PPU-derived information. Further, the PPU-derived information preferably indicates black-out intervals within which the pre-determined cardiac phases cannot occur, and within which the pre-determined cardiac phases are not recognized; or the PPU-derived information indicates window intervals only within which the predetermined cardiac phases can occur, and within which the pre-determined cardiac phases are recognized. Also, the provided synchronization signals preferably further include verification-type signals which indicate whether or not a previous synchronization signal represents a physiologic cardiac phase, and wherein the medical imaging apparatus is controlled to not use for image reconstruction imaging data collected in response to non-physiologic synchronization signals.
In further aspects of the first embodiment, the provided synchronization signals are R-wave-type synchronization signals that signal occurrences of R-waves in the ECG signals, and wherein the step of controlling collects imaging data in a pre-determined temporal relation to R-wave-type signals. Optionally, the pre-determined temporal relation is such that imaging data is collected during cardiac diastole. In one preferable alternative, from the PPU signal, black-out intervals are determined within which physiologic R-wave cannot occur in the ECG signals, and the R-wave-type synchronization signals are not provided during black-out intervals. Where the PPU signal comprises PPU complexes having positive lobes indicating peripheral systolic blood flow, the black-out intervals comprise the duration of the positive lobes of PPU complexes. In another preferable alternative, from the PPU signal, window intervals are determined within which physiologic R-waves in the ECG signal must occur, and the R-wave-type synchronization signals are provided only during window intervals. Where the PPU signal comprises PPU complexes having positive lobes indicating peripheral systolic blood flow, each window interval comprises an interval which begins at a pre-determined duration after the end of a just previous QRS complex in the ECG signal, and which ends at the beginning of the positive lobe of an immediately next PPU complex.
In a second embodiment, the invention includes a magnetic resonance apparatus for acquiring images of a part of a patient placed in an examination zone of the MR apparatus, the apparatus comprising a main magnet system for generating a steady magnetic field in the examination zone, a gradient magnet system for generating temporary gradient magnetic fields in the examination zone, a radio frequency (RF) transmitter system for generating RF pulses in the examination zone, an RF receiver system for receiving MR signals from the examination zone, an ECG system for obtaining ECG signals representing the electrocardiogram of the patient, a peripheral pulse unit system for obtaining PPU signals representing occurrences of peripheral pulses in the patient, a reconstruction unit for reconstructing an image of the region of the patient from the received MR signals, a control unit responsive to one or more synchronization signals for generating control signals controlling the gradient magnet system, the RF transmitter system, the RF receiver system, and the reconstruction unit, wherein the synchronization signals represent occurrences of one or more pre-determined phases of the cyclic movements of the heart, and wherein the control signals cause acquisition of MR data for the reconstruction an image of a part of the patient, and a synchronization unit for providing the one or more synchronization in dependence on both the ECG signals and on the PPU signals in order to synchronize the acquisition of MR signals with cyclic movements of the heart.
In various aspects of the second embodiment, the synchronization unit of the MR apparatus further comprises means for determining, first, PPU-derived information from the PPU signals, wherein the PPU-derived information indicates time intervals within which the pre-determined cardiac phases are physiologically more probable or less probable, and means for recognizing, second, the pre-determined cardiac phases in the ECG signals, wherein the recognizing is responsive to the probability or improbability of the pre-determined cardiac phase indicated by the PPU-derived information. Preferably, the synchronization unit further comprises one or more programmable elements, and one or more memories for storing instructions for causing the synchronization to function for providing the synchronization signals in dependence on both the ECG signals and on the PPU signals.
In a third embodiment the invention includes a computed tomography (CT) x-ray apparatus for acquiring images of a part of a patient placed in an examination zone of the CT apparatus, the apparatus comprising a radiation source, a detector unit which is coupled to the radiation source, means for causing the radiation source and the detector unit to perform a rotational scanning motion about the patient in the examination zone during which scanning motion measuring data is acquired, an ECG system for obtaining ECG signals representing the electrocardiogram of the patient, a peripheral pulse unit system for obtaining PPU signals representing occurrences of peripheral pulses in the patient, a reconstruction unit for reconstructing the spatial distribution of the absorption within the patient from the measuring data acquired by the detector unit, and a control unit responsive to one or more synchronization signals for generating control signals controlling the radiation source, the detector unit, the means for causing a rotational scan, and the reconstruction unit, wherein the synchronization signals represent occurrences of one or more pre-determined phases of the cyclic movements of the heart, and wherein the control signals cause acquisition of measuring data for the reconstruction an image of a part of the patient, and a synchronization unit for providing the one or more synchronization signals in dependence on both the ECG signals and on the PPU signals in order to synchronize the acquisition of measuring data with cyclic movements of the heart.
In a fourth embodiment, the invention includes a computer readable media carrying encoded program instructions for causing a medical imaging apparatus to perform the method of claim 1.

Methods and devices for combined ECG and PPU controlled magnetic resonance imaging


Provided is a starter which reliably cuts off any abnormal current caused to flow through the motor and which can reduce the possibility of current cutoff in the case of normal supply current. According to the present invention, a starter includes: a motor having a field coil; and an electromagnetic switch for supplying an electric current from a battery to the motor to start an engine through a pinion gear, in which: a metal conductor is connected to an upstream side of the field coil to which the electric current is supplied; and the metal conductor has a narrowed portion endowed with a fuse function and having a small sectional area.

1. Field of the Invention
The present invention relates to a starter equipped with a motor having a field coil, and an electromagnetic switch adapted to supply an electric current from a battery to the motor to start an engine through a pinion gear.
2. Description of the Related Art
A known conventional starter is equipped with a motor having an armature to which electricity is supplied from a battery through a brush and adapted to generate a torque in the armature, and an electromagnetic switch for ON/OFF-controlling the battery current caused to flow through the armature, with a part of a pigtail connected to the brush being formed of a low melting point material providing a fuse function (see, for example, JP 2003-148315 A).
In the above conventional starter, when the battery current is continuously supplied to the motor due to failure of the start switch, etc., the pigtail undergoes a fusing to thereby stop the supply of the electricity to the armature, whereby breakage of the starter is prevented.
Likewise, to prevent starter breakage, another known starter is equipped with a brush lead wire one end of which is mechanically and electrically connected to a brush and the other end of which is directly soft-soldered to a movable contact of an electromagnetic switch (see, for example, JP 2005-83259 A).
The pigtail as disclosed in JP 2003-148315 A is connected to a slidable brush, so it can happen that when, for example, the pigtail moves with the brush and comes close to a nearby component, an abnormal current flows to cause the pigtail, which has undergone a fusing, to come into contact with the nearby component to develop a short circuit, making it impossible to cut off the battery current.
In the brush lead wire as disclosed in JP 2005-83259 A, its melting temperature is determined by a soft solder material used, the melting point of which is usually low, so even when normal current is supplied thereto, the brush lead wire may undergo a fusing, making it impossible to start an engine.