The present invention relates in general to implantable, cardiac electrical stimulation devices such as pacemakers or implantable cardioverter-defibrillators. In particular, this invention pertains to a system and method for detecting ventricular capture using far-field sensing of the ventricular R-wave.
Implantable medical devices, such as pacemakers, defibrillators, cardioverters, and implantable cardioverter-defibrillators (xe2x80x9cICDsxe2x80x9d), collectively referred to herein as implantable cardiac stimulating devices, are designed to monitor and stimulate the heart of a patient who suffers from a cardiac arrhythmia. Using leads connected to a patient""s heart, these devices typically stimulate the cardiac muscle (myocardium) by delivering electrical pulses in response to measured cardiac events that are indicative of a cardiac arrhythmia. Properly administered therapeutic electrical pulses often successfully reestablish or maintain the heart""s regular rhythm.
Implantable cardiac stimulating devices can treat a wide range of cardiac arrhythmias by using a series of adjustable parameters to alter the energy, shape, location, and frequency of the therapeutic pulses. The adjustable parameters are usually defined in a computer program stored in a memory of the implantable device. The program, which is responsible for the operation of the implantable device, can be defined or altered telemetrically by a medical practitioner using an external implantable device programmer.
Conventional programmable cardiac stimulation devices are generally of two types: (1) single-chamber, or (2) dual-chamber. In a single-chamber pacemaker, the pacemaker provides stimulation pulses to, and senses cardiac activity within, a single-chamber of the heart, either the right ventricle or the right atrium. In a dual-chamber pacemaker, the pacemaker provides stimulation pulses to, and senses cardiac activity within, two chambers of the heart, e.g., both the right atrium and the right ventricle. The left atrium and left ventricle can also be sensed and paced, provided that suitable electrical contacts are effected therewith. The recent development of multi-chamber cardiac stimulation devices allows sensing and pacing in up to all four chambers of the heart. Recent clinical evidence suggests multi-chamber stimulation may have important hemodynamic benefit in patients suffering from heart failure and may be effective in preventing arrhythmias in patients prone to sustained or frequent arrhythmias.
Cardiac stimulation devices have a great number of adjustable parameters that must be tailored to a particular patient""s therapeutic needs. One adjustable parameter of particular importance is the output stimulation energy. For the stimulation device to perform its intended function, it is critically important that the delivered electrical stimuli be of sufficient energy to depolarize the cardiac tissue, a condition known as xe2x80x9ccapturexe2x80x9d.
When a pacemaker stimulation pulse stimulates either the atrium or the ventricle during an appropriate portion of a cardiac cycle, it is desirable to have the heart properly respond to the stimulus provided. Every patient has a xe2x80x9ccapture thresholdxe2x80x9d which is generally defined as the minimum amount of stimulation energy necessary to effect capture. Capture should be achieved at the lowest possible energy setting yet provide enough of a safety margin so that, should a patient""s threshold increase, the output of an implantable stimulation device, i.e. the stimulation energy, will still be sufficient to maintain capture. Dual-chamber and multi-chamber stimulation devices may have differing atrial and ventricular stimulation energy that correspond to the capture thresholds of the targeted cardiac chamber.
The earliest pacemakers had a predetermined and unchangeable stimulation energy, which proved to be problematic because the capture threshold is not a static value and may be affected by a variety of physiological and other factors. For example, certain cardiac medications may temporarily raise or lower the threshold from its normal value. In another example, fibrous tissue that forms around stimulation electrodes within several months after implantation may raise the capture threshold.
As a result, some patients eventually suffered from loss of capture as their pacemakers were unable to adjust the pre-set stimulation energy to match the changed capture thresholds. One attempted solution was to set the level of stimulation pulses fairly high so as to avoid loss of capture due to a change in the capture threshold. However, this approach resulted in some discomfort to patients who were forced to endure unnecessarily high levels of cardiac stimulation. Furthermore, such stimulation pulses consumed extra battery resources, thus shortening the useful life of the pacemaker.
When programmable pacemakers were developed, the stimulation energy was implemented as an adjustable parameter that could be set or changed by a medical practitioner. Typically, such adjustments were effected by the medical practitioner using an external programmer capable of communication with an implanted pacemaker via a magnet applied to a patient""s chest or via telemetry. The particular setting for the pacemaker""s stimulation energy was usually derived from the results of extensive physiological tests performed by the medical practitioner to determine the patient""s capture threshold, from the patient""s medical history, and from a listing of the patient""s medications. While the adjustable stimulation energy feature proved to be superior to the previously known fixed energy, some significant problems remained unsolved. In particular, when a patient""s capture threshold changed, the patient was forced to visit the medical practitioner to adjust the stimulation energy accordingly.
To address this pressing problem, pacemaker manufacturers have developed advanced stimulation devices that are capable of determining a patient""s capture threshold and automatically adjusting the stimulation pulses to a level just above that which is needed to maintain capture. This automatic capture feature improves the patient""s comfort, reduces the necessity of unscheduled visits to the medical practitioner, and increases the pacemaker""s battery life by conserving the energy used to generate stimulation pulses.
However, many of these advanced pacemakers require additional circuitry and/or special sensors that must be dedicated to capture verification. This requirement increases the complexity of the pacemaker system and reduces the precious space available within a pacemaker""s casing, and also increases the pacemaker""s cost. As a result, pacemaker manufacturers have attempted to develop automatic capture verification techniques that may be implemented in a typical programmable pacemaker without requiring additional circuitry or special dedicated sensors.
A common technique used to determine whether capture has been effected is monitoring the patient""s cardiac activity and searching for the presence of an xe2x80x9cevoked responsexe2x80x9d following a stimulation pulse. The evoked response is the response of the heart to the application of a stimulation pulse. The patient""s heart activity is typically monitored by the stimulation device by keeping track of the stimulation pulses delivered to the heart and examining, through the leads connected to the heart, electrical signals that are manifest concurrent with depolarization or contraction of muscle tissue (myocardial tissue) of the heart. The contraction of atrial muscle tissue is evidenced by generation of a P-wave, while the contraction of ventricular muscle tissue is evidenced by generation of an R-wave (sometimes referred to as the xe2x80x9cQRSxe2x80x9d complex).
When capture occurs, the evoked response is an intracardiac P-wave or R-wave that indicates contraction of the respective cardiac tissue in response to the applied stimulation pulse. For example, using such an evoked response technique, if a stimulation pulse is applied to the ventricle, a response sensed by ventricular sensing circuits of the stimulation device immediately following the application of the stimulation pulse is presumed to be an evoked response that evidences capture of the ventricle.
However, it is for several reasons very difficult to detect a true evoked response. First, because the ventricular evoked response is a relatively small signal, it may be obscured by a high-energy stimulation pulse and therefore difficult to detect and identify. Second, the signal sensed by the stimulation device""s sensing circuitry immediately following the application of a stimulation pulse may be not an evoked response but noise, such as electrical noise caused, for example, by electromagnetic interference, or myocardial noise caused by random myocardial or other muscle contraction.
Another signal that interferes with the detection of an evoked response, and potentially the most difficult for which to compensate because it is usually present in varying degrees, is lead polarization. A lead/tissue interface is that point at which an electrode of the stimulation lead contacts the cardiac tissue. Lead polarization is commonly caused by electrochemical reactions that occur at the lead/tissue interface due to application of an electrical stimulation pulse, such as a stimulation pulse, across the interface.
Because the evoked response is sensed through the same lead electrodes through which the stimulation pulses are delivered, the resulting polarization signal, also referred to as an xe2x80x9cafterpotentialxe2x80x9d, formed at the electrode can corrupt the evoked response that is sensed by the sensing circuits. This undesirable situation occurs often because the polarization signal can be three or more orders of magnitude greater than the evoked response. Furthermore, the lead polarization signal is not easily characterized; it is a complex function of the lead materials, lead geometry, tissue impedance, stimulation energy and other variables, many of which are continually changing over time.
In each of the above cases, the result may be a false positive detection of an evoked response. Such an error leads to a false capture indication, which in turn, leads to missed heartbeats, a highly undesirable and potentially life-threatening situation. In dual chamber and multichamber stimulation, successful capture all stimulated chambers is critical to maintaining proper synchrony of heart chamber contractions. Loss of optimal atrial-ventricular synchrony or inter-ventricular synchrony may have deleterious hemodynamic effects.
Another problem results from a failure by the stimulation device to detect an evoked response that has actually occurred. In that case, a loss of capture is indicated when capture is in fact present, also an undesirable situation that will cause the device to unnecessarily deliver a high-energy back-up stimulation pulse and invoke the threshold search function in a chamber of the heart.
Automatic threshold testing is invoked by the stimulation device when loss of ventricular capture is detected or on a predetermined periodic basis. An exemplary threshold test is performed as follows. When loss of capture is detected, the device increases the stimulation pulse energy to a relatively high predetermined testing level at which capture is certain to occur, and thereafter decrements the output energy until capture is lost. The stimulation energy is then set to a level slightly above the lowest output energy at which capture was still detected. Thus, capture verification is of utmost importance in proper determination of the stimulation energy.
When a ventricular stimulation pulse is properly captured in the ventricle, a subsequent ventricular contraction results in an R-wave which may be sensed through an atrial lead, in patients with intact atrioventricular (xe2x80x9cAVxe2x80x9d) conduction, as a xe2x80x9cfar-fieldxe2x80x9d signal, also referred to herein as xe2x80x9cfar-field R-wavexe2x80x9d or xe2x80x9cfar-field evoked responsexe2x80x9d. The far-field R-wave confirms successful ventricular capture because the ventricular contraction only occurs after a properly captured ventricular stimulation pulse.
However, previously known dual-chamber and multi-chamber pacemakers do not sense ventricular activity through the atrial lead for a particular interval of time (i.e., the xe2x80x9cpost-ventricular atrial refractory period,xe2x80x9d commonly known as PVARP) subsequent to the delivery of the ventricular stimulation pulse. This refractory period on the atrial channel following ventricular stimulation prevents the atrial channel from mistaking a far-field R-wave for an atrial P-wave. However, detection of the far-field R-wave can be advantageous in verifying that ventricular capture has occurred.
It would thus be desirable to provide a system and method for automating the detection of capture on one or both ventricular channels of an implantable multi-chamber stimulation device, with increased accuracy. It would also be desirable to provide a system and method for reducing the negative effect of polarization and noise on capture verification. It would further be desirable to enable the stimulation device to perform ventricular capture verification without requiring dedicated circuitry and/or special sensors.
The present invention addresses these needs by providing a system and method for automatically detecting capture of a ventricular chamber in a multi-chamber cardiac stimulation device. Ventricular capture is detected by sensing the far-field R-wave that follows a ventricular stimulation pulse that has successfully captured the ventricle.
In one illustrative embodiment of the invention, the device delivers a ventricular stimulation pulse to both the right and left ventricles and then samples a far-field R-wave, resulting from the biventricular evoked response, on the atrial channel during a predetermined far-field interval window.
In another illustrative embodiment, the device delivers a ventricular stimulation pulse to one ventricle and then samples a far-field evoked response on a pair of atrial channels during a predetermined far-field interval window.
In certain embodiments, capture may be verified by comparing one or more signal characteristics of the far-field R-wave sample, such as peak amplitude, integral, or slope, to the same characteristic(s) of an expected far-field R-wave following an evoked response in the designated ventricle.


The present disclosure generally relates to dental care. More specifically, the present disclosure relates to oral care products for the improved mineralization/remineralization of teeth.
Enamel and dentin in teeth are primarily composed of calcium phosphate in the form of calcium hydroxyapatite. This material is highly insoluble at neutral salivary pH levels, but tends to dissolve in acidic media. Consequently, when teeth are exposed to acids generated during the bacterial-induced glycolysis of carbohydrates, lesions or demineralized areas are initiated below the surface of intact enamel since the outer rim is more acid resistant. Dental caries begin with these subsurface lesions, which are formed before a cavity is even detectable. If not treated, the surface enamel above such a subsurface lesion will eventually collapse, resulting in the formation of a cavity and subsequent loss of tooth structure.


This application generally relates to communications and, more particularly, to detecting encrypted path finding or routing a message with an address header.
Encryption of communications is increasing. More and more people, businesses, and governments are encrypting their electronic communications. This encryption provides enhanced security and privacy for these electronic communications.
Encryption, however, is a problem for communications service providers. Communications service providers need to know the type of data contained within an electronic communication. Some data types receive priority processing, while other data types are queued for later processing. Encryption, however, hides the contents of the communication and often prevents a communications service provider from determining the level of required processing. Because the communications service provider cannot determine the level of required processing, the encrypted communication defaults to lesser priority and/or processing.
Internet telephony provides an example. Internet telephone calls should be processed to result in a real time, or nearly real time, conversation. If packets are lost, or if packets experience congestion, the quality of the call suffers. Internet telephone calls, then, should receive priority processing. When a communications service provider detects data representing an Internet telephone call, the service provider gives that data priority/special processing to reduce packet loss and to reduce latency effects. Encryption, however, hides the contents of the communication. Encryption prevents the communications service provider from determining whether priority and/or special processing is required. So, even though the communication is an Internet telephone call, encryption causes the communication to default to lesser priority and/or processing. The quality of the call may then suffer from packet loss and congestion.
There is, accordingly, a need in the art for improved determination of data types. When parties encrypt their communications, there is a need for determining the type of data contained inside the encrypted communication. There is also a need for identifying a particular kind of encrypted traffic in order to provide prioritized/specialized processing.


Dynamic range is the ratio of intensity of the highest luminance parts of a scene and the lowest luminance parts of a scene. For example, the image projected by a video projection system may have a maximum dynamic range of 300:1.
The human visual system is capable of recognizing features in scenes which have very high dynamic ranges. For example, a person can look into the shadows of an unlit garage on a brightly sunlit day and see details of objects in the shadows even though the luminance in adjacent sunlit areas may be thousands of times greater than the luminance in the shadow parts of the scene. To create a realistic rendering of such a scene can require a display having a dynamic range in excess of 1000:1. The term “high dynamic range” means dynamic ranges of 800:1 or more.
Modern digital imaging systems are capable of capturing and recording digital representations of scenes in which the dynamic range of the scene is preserved. Computer imaging systems are capable of synthesizing images having high dynamic ranges. However, current display technology is not capable of rendering images in a manner which faithfully reproduces high dynamic ranges.
Blackham et al., U.S. Pat. No. 5,978,142 discloses a system for projecting an image onto a screen. The system has first and second light modulators which both modulate light from a light source. Each of the light modulators modulates light from the source at the pixel level. Light modulated by both of the light modulators is projected onto the screen.
Gibbon et al., PCT Application No. PCT/US01/21367 discloses a projection system which includes a pre modulator. The pre modulator controls the amount of light incident on a deformable mirror display device. A separate pre-modulator may be used to darken a selected area (e.g. a quadrant).
There exists a need for cost effective displays capable of reproducing a wide range of light intensities in displayed images.


Various hair implantation procedures and equipment associated with the implementation thereof have been employed in the prior art. Follicular unit hair transplantation is the procedure most commonly used. This procedure is however invasive since it involves removal of a strip of the scalp from a donor area and placement of the graft at a recipient area. Such strip removal necessitates shaving and leaves a scar that is difficult to heal, thereby posing restrictions in the client's normal activities over a rather long healing period. The process is rather slow with short daily sessions enabling implantation of a limited number of hair of the order of 500 units, whilst its efficiency is rather low due to a large percentage of up to 20% of follicles being damaged during the removal of the strip and the subsequent division thereof in individual follicles to be implanted into the recipient zone. Eventually since a number of sessions must take place to perform the overall hair transplantation process and since such sessions have to be scheduled with extensively long intervals in between, it becomes uncomfortably long to complete the process. Furthermore, placement of hair follicles is subsequently performed by means of forceps thereby leaving much room for human error that often leads to oddly directioned hair at incorrect angles instead of the desired natural result of evenly angled hair. Moreover such graft extraction and subsequent implanting process is not available for all clients, e.g. very curly hair cannot be extracted, and a preliminary test has to be conducted to determine whether the process is suitable for each particular candidate.
The object of the present invention is to overcome and eliminate the abovementioned disadvantages and drawbacks of the prior art. With this scope in mind, the invention proposes a minimally invasive hair transplantation process that is available to all potential candidates without exception and requires neither shaving of the scalp nor removal of grafts or any preliminary testing whatsoever. Instead single hair follicles are extracted from a donor region to be subsequently implanted at a recipient region. The process is fast providing the possibility of an approximate number of 5,000 hair units being extracted in one session.
The object of the invention is further to disclose preferred specialized tools for the implementation of the abovementioned direct hair implantation process and in particular to propose alternative embodiments of tool devices as follows:                a. a hair harvesting device adapted to perform cutting of individual hair follicles comprising a tubular cutting head with a conical knife edge cutting surface formed at one end thereof or with conical knife edge cutting surfaces of different diameters formed at two ends thereof.        b. a hair harvesting device comprising a cross like pattern of tubular cutting heads, each one being formed with a conical knife edge cutting surface of different diameter allowing removal of follicular hair units of varying diameters with a single harvesting instrument.        c. a hair implanting device comprising a hollow needle having a longitudinal groove at a frontal portion thereof with an obliquely cut free end adapted to receive a follicular hair unit, a sliding rod being reciprocatingly movable axially along the needle to effect placement of the follicular hair unit disposed within the groove of the frontal end of the needle within a predetermined position of the scalp at the recipient bald area, and a tubular housing adapted to receive said needle and said sliding rod incorporating means of performing the hair implanting operation.
It is a further object of the invention to provide the aforementioned hair implanting device with means of appropriately regulating and fine adjustment of the depth of intrusion of the needle into the scalp to provide for optimum performance of the hair implanting device.
Another object of the invention is to disclose an electrically operated mode of the hair transplanting device.
A final object of the invention, in view of accelerating the hair transplantation process by avoiding the step of the tiresome exchange of instruments, is to provide a combined hair harvesting and hair implanting device operated preferably manually when effecting hair harvesting and preferably electrically when effecting hair implantation, wherein the aforementioned knife edge cutting surface of the hair harvesting device is obliquely cut so as to be adapted to perform the combined role of the follicular hair unit receiving groove of the hair implanting device.


1. Field of the Invention
This invention relates generally to wireless and long distance carriers, Internet service providers (ISPs), and information content delivery services/providers and long distance carriers. More particularly, it relates to location services for the wireless industry.
2. Background of Related Art
The Location Interoperability Forum (LIF), the Wireless Application Protocol (WAP) Forum, and 3rd Generation Partnership Project (3GPP) have attempted to define an area trigger via Application Protocol Interfaces (APIs) specific to these groups.
The problem with the above solutions is that they are not well defined or do not implement schemes that would permit functionality to support area watching features such as are provided by the present invention.


A middlebox is a network appliance that manipulates internet traffic by optimizing data flow across the network. Middleboxes can be configured as wide area network (“WAN”) optimizers and can be deployed in pairs across two geographically separated locations to optimize data traffic between the two middleboxes. Middleboxes can be connected through a single link or multiple links such as a leased line link and a broadband link. Middleboxes use TCP congestion avoidance algorithms, commonly called “TCP flavors,” to optimize TCP data flows as part of a quality of service (“QoS”) scheme. Common examples of TCP avoidance flavors can include algorithms such as TCP Vegas, TCP Reno, TCP NewReno, TCP Hybla, TCP BIC, and TCP CUBIC, among others. Each TCP congestion avoidance flavor is suited for optimizing data flows originating from or received by particular operating systems, link types, and/or other network characteristics.
Some TCP flavors improve quality of service across TCP connections by using congestion control and congestion avoidance techniques that sometimes include TCP traffic prioritization. Traffic prioritization, a traffic shaping technique for Quality of Service (QoS), can ensure that more packets from very high priority (P1) traffic are pushed into the network for increased throughput. Thus when there are enough data to be sent from both P1 and non-high priority (non-P1) traffic, the prioritization functionality of QoS can push more packets from P1 traffic into the network pipe thereby delivering better throughput and providing enhanced QoS for P1 traffic. For example, using conventional methods of prioritization, if traffic prioritization module dictates 3:1 ratio for P1 and non-P1 traffic, we could expect approximately 75% of the packets occupying the leased network pipe to be of P1 traffic.
One down side of conventional prioritization techniques is when the network link gets congested, since there are more packets from the P1 traffic, the probability of packet drops from P1 traffic is much higher than the probability of packet drops in non-P1 traffic. For example, in one congestion scenario, the probability of next packet drop to occur in P1 traffic would be 0.75 as opposed to non-P1 traffic with a probability of 0.25. Thus, using conventional traffic prioritization techniques, P1 traffic could get multiple packet drops, which in turn forces the TCP connection to reduce its congestion window. Therefore, the higher priority TCP traffic can experience reduced throughput and degraded end-to-end QoS.


It is known in the art relating to oral swabs to apply vacuum force through a porous foam sleeve or through an aperture in the foam sleeve to remove liquid and other material from the mouth of a patient. Such oral swabs clog as the porous surface of the foam sleeve becomes filled or as the aperture in the foam sleeve becomes restricted with debris.
In addition, such oral swabs preclude removal of viscus fluid and/or material from oral recesses and recesses between the teeth and gum line. Often times the vacuum force drawn through the foam sleeve collapses the foam into the device and/or onto itself and causes the swab to fail to continue suctioning. Such side hole devices are difficult to manufacture as the foam sleeve must be properly placed on a vacuum supply tube end to ensure flow through the element. In some cases, an aperture in the foam sleeve must be aligned relative to an aperture in the vacuum supply tube end.


To a transmission line configuring a network for optical communication; an optical amplifier provided in this transmission line; or an optical transceiver, an optical transponder, or the like that performs optical communication, an optical power attenuator may be provided to adjust an optical power.
Furthermore, as the optical power attenuator, known is one of a reflective type provided with a MEMS (microelectromechanical-system) element that can control a reflection angle of a mirror that reflects a light according to an applied voltage.
The MEMS element used in the optical power attenuator of the reflective type is provided with the mirror, which is pivotably supported via a beam, and is configured to be able to adjust the reflection angle of the light by the mirror by an electrostatic force arising according to the applied voltage (see for example patent literature 1).
Furthermore, as illustrated in FIG. 5, a conventional optical power attenuator 5 is provided with a MEMS element 10 configured as above, a capillary member 22 provided to one end of a two-core optical fiber 20 for inputting/outputting a light, and a lens 30 disposed between the capillary member 22 and the MEMS element 10.
Furthermore, the lens 30 is configured as a collimating lens; it converts an incident light from an IN-side optical fiber 20i among the two-core optical fiber 20 into a collimated light (parallel light), causes this to become incident to the MEMS element 10, and causes a reflected light from the MEMS element 10 to become incident to an OUT-side optical fiber 20o in a path different from an incoming path.
Because of this, the incident light from the IN-side optical fiber 20i is attenuated according to a reflection angle of the light by a mirror in the MEMS element 10, becomes incident to the OUT-side optical fiber 20o, and is transmitted to another optical device via the OUT-side optical fiber 20o.


1. Field of the Invention
The invention relates in general to a touch interface and an operating method thereof, and more particularly to a touch control electronic device and an operating method thereof.
2. Description of the Related Art
Conventionally, communication interfaces between human and computers or machines are mainly based on keyboards and mice. With the trend of the technological product toward the friendlier man-machine interface, the applications of the touch interfaces become more and more popularized. Recently, the flourishing development of the highly technological industry brings the development of the information and consumer products. The user is eager for an operation interface that can be easily operated so that the touch interface has become the design stream of the product.
In the field of the mobile technology, handheld electronic devices, such as a personal digital assistant (PDA), a smart phone, a portable video game, a portable multimedia player and a portable navigation device, also adopt touch panels to satisfy the miniaturized design trend. In addition, the touch inducing manipulation method of the recently developed touch wheel has overcome the conventional mechanical manipulation method, in which typical keys and a scroll wheel are equipped. The touch wheel may directly sense the circular movement of the user's finger. The user only has to put his/her finger on the touch wheel and to slide, rotate or touch the peripheral and middle keys of the wheel to select the items on the screen, to adjust the volume, or to click the songs so that the handheld electronic device can be easily operated.
Thus, it is a new direction for the future product development to effectively apply the touch interface to create the new product using the method so that the user can operate the touch interface more conveniently and instinctively and the man-machine interaction effectiveness of the user can be enhanced.


In the fabrication of ultra-large scale-integration (ULSI) circuits it has been very common to utilize vertical stacking, or vertical integration, of metal wiring circuits to form multilevel interconnection. Multilevel fabrication process has become an efficient way to increase circuit performance and increase the functional complexity of the circuits. One drawback of multilevel interconnection is the loss of topological planarity resulting from various photolithographic and etching processes. The various integrated circuit fabrication processes invariably produce nonplanar surface, or nonplanar topography, on the wafer, from which semiconductor devices are fabricated. During the multilevel metallization of VLSI or ULSI devices, the multiplicity of layers of nonplanar surfaces further add together to cause even more serious topography problems. For example, the conductive or insulative properties of the various deposited films can be degraded on the area of the film layers across the step height. Those films in high topography areas can be easily broken during heat, electrical current, or mechanical stress steps, resulting in the pattern areas becoming discontinuous. Such discontinuity can cause failures in the device to perform certain intended functions. Furthermore, a nonplanar surface cannot be precisely focused during the photolithography process, because the depth of focus of the conventional photolithographic stepper will be deviated by different step heights of the wafer. Such an out-of-focus problem is more profound with respect to device features of very small sizes.
To alleviate these problems, the wafer is planarized at various stages in the fabrication process to minimize non-planar topography and thus its adverse effects. Such planarization is typically implemented in the dielectric layers. However, it is also possible to implement the planarization process in the conductor layer. More recently, chemical-mechanical polishing (CMP) processes have become very well received to planarize the wafer surface in preparation for further device fabrication. The CMP process mainly involves the step of holding a semiconductor wafer against a rotating polishing pad surface wetted by a polishing slurry, which typically comprises an acidic or basic etching solution in combination with alumina or silica particles. On the one hand, the liquid portion of the slurry chemically removes, loosens, or modifies the composition of the material on the wafer which is to be removed. On the other hand, the particle portion of the slurry, in combination of the rotating polishing pad, physically removes the chemical modified material from the wafer. Thus, the name "chemical-mechanical polishing" was obtained.
One of the most commonly used sacrificial materials in the chemical-mechanical polishing process is a solution-type silicon dioxide, which is commonly referred to as the spin-on-glass (SOG). The SiO.sub.2 -based SOG is initially formed as a low viscosity solution which can be coated onto the nonplanar surface to quickly fill the recessed areas by a conventional spin coating technique. After the SOG coating, the coated layer is hard-baked to remove the solvent contained therein and turn the SOG layer into a hardened layer. Because of its high electrical resistance, the solidified SOG layer on top of the integrated circuit structure (i.e., the metal layer) must be etched back, typically by a chemical-mechanical polishing procedure using an abrasive slurry containing hydrogen fluoride in the chemical portion of the polishing procedure. If the SOG layer on the top surface of the wafer is not completely removed, it can generate the so-called vias poisoning, causing the vias to have a very high electrical resistance and adversely affect the interlayer conduction.
One of the commonly observed problems in using SOG during the planarization process is the so-called dishing effect. The etching process is not a selective process and it will remove all the affected material on the wafer surface. During the chemical-mechanical polishing of the SOG layer, the portion of the SOG layer inside the trenches can be affected by the etching solution being dished out from the mechanical polisher, resulting another type of un-planarized top surface. Many times, the dishing effect could cause even more serious nonplanar surface on the wafer. One way to ameliorate the dishing effect in the etch back process is to use a etch-back photoresist. However, this would require an extra photolithography process using an extra photo mask to remove the sacrificial material above the patterned structure. This can add substantially to the total manufacturing cost.
Another way to avoid such dishing effect is to use a non-silicon-based polymeric material, such as polyimide, which exhibits excellent chemical and electrical resistance, as the sacrificial material for chemical-mechanical polishing processes. The polymer-based sacrificial material, however, will not be removed by the conventional chemical-mechanical polishing slurry designed for SOG. Thus, the IC manufacturers must stock two different types of chemical-mechanical polishing slurries. And the use of a different chemical-mechanical polishing slurry may cause material compatibility problems and other handling concerns. In a co-pending application, it was demonstrated that excellent result can be obtained by treating the polymeric material so that it becomes removable by hydrofluoric acid. However, in semiconductor devices which contain relatively wide trenches, the polymeric sacrificial layer will be warped into the trench bottom, and the dishing effect can again become significant.
U.S. Pat. No. 4,944,836 disclosed a chemical-mechanical polishing method for producing coplanar metal-insulator films on a substrate. It taught the conventional approach of using silicon dioxide based slurry to provide a planarized surface by chemical-mechanical polishing. However, when the layer thickness of the semiconductor device becomes increasing thin, and the depth of the trench becomes correspondingly shallow, the dishing effect caused by the exposure of the silicon dioxide in the trench area becomes relatively more profound.
U.S. Pat. No. 5,169,491 disclosed a method for planarizing SiO.sub.2 -containing dielectric in semiconductor wafer processing. It involved the steps of (1) providing a layer of undoped SiO.sub.2 atop a wafer; (b) depositing a layer of borophosphosilicate glass (BPSG) atop the layer of undoped SiO.sub.2 ; and (c) chemical mechanical polishing the borophosphosilicate glass selectively relative to the underlying layer of undoped SiO.sub.2 and using the underlying layer of undoped SiO.sub.2 as an etching stop.
U.S. Pat. No. 5,314,843 disclosed a method for planarizing a semiconductor wafer using the chemical-mechanical polishing process. The method included the steps of (1) masking the semiconductor wafer surface layer to define first and second laterally adjacent portions; (2) altering only the first portion of the surface layer of material to polish at a different removal rate in the chemical-mechanical polishing process than the second portion of the surface layer; and (3) polishing the surface in the chemical-mechanical polishing process. As discussed before, the method disclosed in the '843 patent may minimize the dishing effect, but it requires an additional expensive photolithography step.


Modern vehicles (e.g., airplanes, boats, trains, cars, trucks, etc.) can include a vehicle event recorder in order to better understand the timeline of an anomalous event (e.g., an accident). A vehicle event recorder typically includes a set of sensors, e.g., video recorders, audio recorders, accelerometers, gyroscopes, vehicle state sensors, GPS (global positioning system), etc., that report data, which is used to determine the occurrence of an anomalous event. If an anomalous event is detected, the sensor data related to the event is stored for later review. A vehicle event recorder for cars and trucks (e.g., vehicles that operate on public roads) can include road map data comprising location-specific legal information (e.g., speed limit information, stop sign information, traffic light information, yield sign information, etc.). Location-specific legal information can be used to identify an anomalous event in the case of the vehicle acting against the law (e.g., traveling in excess of the speed limit, rolling through a stop sign, etc.). If there is an error in the legal information, anomalous events can be incorrectly identified, possibly leading to unnecessary expense as the event is processed, stored, and/or transmitted.


1. Field of the Invention
This invention relates to aroma therapy delivery systems, and more particularly to aroma therapy delivery systems incorporating a shaving unit as the delivery vehicle.
2. Description of the Background Art
Various conventional wet shavers disclose the general concept of applying scented substances to a user's skin as lubricating agents during the shaving process.
For example, U.S. Pat. No. 4,850,107 issued to Valliades et al. on Jul. 25, 1989 discloses a razor assembly with means for intermittently distributing a thin fluid film beneath the bottom of the blade while shaving. The '107 patent discloses an open recessed seating area on the upper, angled portion of the razor shaft for housing a sponge. By applying pressure to the sponge, a thin fluid is released through channels onto the face. The '107 patent teaches that the thin fluid, which may be a scented fluid, may be released on demand to moisten the skin of the user while shaving.
U.S. Pat. No. 4,875,287 issued to Creasy et al. on Oct. 24, 1989 discloses a razor head having a coated surface or substrate which provides, inter alia, a lubricant to the user's face. The '287 patent discloses that the additional materials can be incorporated into the polymer blends such as fragrances.
U.S. Pat. No. 5,134,775 issued to Althaus et al. on Aug. 4, 1992 discloses a shaver head for a wet shaver comprising a device for receiving a liquid shaving preparation which is dispensed during shaving. The '775 patent discloses that the liquid shaving preparation can be perfumed.
U.S. Pat. No. 5,121,541 issued to Patrakis on Jun. 16, 1992 discloses an electric razor comprising a misting mechanism for misting a lubricating agent, such as water, cologne or a beard softener, onto the user's skin while shaving.
While these publications appear to disclose the general concept of using scented lotions or lubricating agents to be applied to a user's face while shaving, they fail to teach an aroma therapy delivery system or aroma therapy delivery systems incorporating a shaving unit as the delivery vehicle which dispense an aroma therapy.
Accordingly, it is the primary object of the present invention to provide a shaver assembly unit which dispenses an aromatic therapy.
It is a further object of the invention to provide a shaver assembly unit that can be easily filled with an aromatic agent.


1. Field of Art
The disclosure generally relates to the field of data collection and data mining in computing devices.
2. Description of Art
As mobile computing technology advances, more and more applications become available for mobile computing devices. As a result, users use the mobile computing devices to perform more activities. In addition, mobile computing devices are also equipped with increasing number of sensors such as Global Positioning System (GPS) receivers, accelerometers, and proximity sensors. These sensors, coupled with the increased number of applications, give users access to even more information than has previously been available.
The information from the different sources has inherently relationships (e.g., the GPS receiver tracks the current geographic location while the calendar application provides the user's scheduling information). Currently, there is no solution to automatically collect and analyze the user information available on multiple sources of the mobile computing device to discover the inherent relationships and to provide the user with summaries of the collected user information and the relationships. Accordingly, there is lacking in the art, inter alia, techniques for collecting and analyzing user activities on a mobile computing device.


Recent fuel developments have resulted in a number of aqueous fuel emulsions comprised essentially of a carbon based fuel, water, and various additives such as lubricants, emulsifiers, surfactants, corrosion inhibitors, cetane improvers, and the like. These aqueous fuel emulsions may play a key role in finding a cost-effective way for internal combustion engines including, but not limited to, compression ignition engines (i.e. diesel engines) to achieve the reduction in emissions below the mandated levels without significant modifications to the engines, fuel systems, or existing fuel delivery infrastructure.
Advantageously, aqueous fuel emulsions tend to reduce or inhibit the formation of nitrogen oxides (NOx) and particulates (i.e. combination of soot and hydrocarbons) by altering the way the fuel is burned in the engine. Specifically, the fuel emulsions are burned at somewhat lower temperatures than a conventional fuels due to the presence of water. This, coupled with the realization that at higher peak combustion temperatures, more NOx are typically produced in the engine exhaust, one can readily understand the advantage of using aqueous fuel emulsions.
A major concern of aqueous fuel emulsions or water blend fuels, however, is the stability of the fuel. As is well known in the art, the constituent parts of such aqueous fuel emulsions have a tendency to separate over time. Blending of the fuel emulsions in a manner to achieve long-term stability is essential if such fuels are to be commercially successful. The problems associated with fuel emulsion separation are very severe inasmuch as most engine operating characteristics are adjusted for a prescribed fuel composition. Where the fuel emulsion composition has changed due to ingredient separation, the engine performance is markedly diminished.
Several related art references have disclosed various devices or techniques for producing or blending a fuel emulsion for internal combustion engines. For example, U.S. Pat. No. 5,535,708 (Valentine) discloses a process for forming an emulsion of an aqueous urea solution in diesel fuel and combusting the same for the purposes of reducing NOx emissions from diesel engines. See also U.S. Pat. No. 4,938,606 (Kunz) discloses an apparatus for producing an emulsion for internal combustion engines that employs an oil line, a water line, a dosing apparatus and various mixing and storage chambers. Another related art process and system for blending a fuel emulsion is disclosed in U.S. Pat. No. 5,298,230 (Argabright) which discloses a specialized process for blending a fuel emulsification system useful for the reduction of NOx in a gas turbine.
The present invention addresses the aforementioned problems associated with separation of aqueous fuel emulsions by providing a blending system and method that enhances the long term stability of such emulsions.


1. Field of the Invention
The present invention relates to a magnetoresistive element using a method of reducing magnetic field inverting magnetization thereinafter, referred to as switching field of a magnetic film, a memory element having the magnetoresistive element, and a memory using the memory element.
2. Related Background Art
In recent years, semiconductor memories as solid-state memories are adopted in many information devices, and are of various types such as a DRAM, FeRAM, and flash EEPROM. The characteristics of the semiconductor memories have merits and demerits. There is no memory which satisfies all specifications required by current information devices. For example, the DRAM achieves high recording density and large rewritable count, but is volatile and loses its information upon power-off. The flash EEPROM is nonvolatile, but takes a long erase time and is not suitable for high-speed information processing.
Under the present circumstances of semiconductor memories, a magnetic memory (MRAM: Magnetic Random Access Memory) using a magnetoresistive element is promising as a memory which satisfies all specifications required by many information devices in terms of the recording time, read time, recording density, rewritable count, power consumption, and the like. In particular, an MRAM using a spin-dependent tunneling magnetoresistive (TMR) effect is advantageous in high-density recording or high-speed read because a large read signal can be obtained. Recent research reports verify the feasibility of MRAMs.
The basic structure of a magnetoresistive film used as an MRAM element is a sandwich structure in which magnetic layers are formed adjacent to each other via a nonmagnetic layer. Known examples of the material of the nonmagnetic film are Cu and Al2O3. A magnetoresistive film using a conductor such as Cu in a nonmagnetic layer is called a GMR film (Giant MagnetoResistive film). A magnetoresistive film using an insulator such as Al2O3 is called a spin-dependent TMR film (Tunneling MagnetoResistive film). In general, the TMR film exhibits a larger magnetoresistance effect than the GMR film.
When the magnetization directions of two magnetic layers are parallel to each other, as shown in FIG. 13A, the resistance of the magnetoresistive film is relatively low. When these magnetization directions are antiparallel, as shown in FIG. 13B, the resistance is relatively high. One of the magnetic layers is formed as a recording layer, and the other layer is as a read layer. Information can be read out by utilizing the above property. For example, a magnetic layer 13 on a nonmagnetic layer 12 is formed as a recording layer, and a magnetic layer 14 below the nonmagnetic layer 12 is as a read layer. The rightward magnetization direction of the recording layer is defined as xe2x80x9c1xe2x80x9d, and the leftward direction is as xe2x80x9c0xe2x80x9d. If the magnetization directions of the two magnetic layers are rightward, as shown in FIG. 14A, the resistance of the magnetoresistive film is relatively low. If the magnetization direction of the read layer is rightward and that of the recording layer is leftward, as shown in FIG. 14B, the resistance is relatively high. If the magnetization direction of the read layer is leftward and that of the recording layer is rightward, as shown in FIG. 14C, the resistance is relatively high. If the magnetization directions of the two magnetic layers are leftward, as shown in FIG. 14D, the resistance is relatively low. That is, when the magnetization direction of the read layer is pinned rightward, xe2x80x9c0xe2x80x9d is recorded in the recording layer for a high resistance, and xe2x80x9c1xe2x80x9d is recorded for a low resistance. Alternatively, when the magnetization direction of the read layer is pinned leftward, xe2x80x9c1xe2x80x9d is recorded in the recording layer for a high resistance, and xe2x80x9c0xe2x80x9d is recorded for a low resistance.
As the element is downsized for a higher recording density of an MRAM, the MRAM using an in-plane magnetization film becomes more difficult to hold information under the influence of a demagnetizing field or magnetization curling at the end face. To avoid this problem, for example, a magnetic layer is formed into a rectangle. This method cannot downsize the element, so an increase in recording density cannot be expected. U.S. Pat. No. 6,219,275 has proposed the use of a perpendicular magnetization film to avoid the above problem. According to this method, the magnetizing field does not increase even with a smaller element size. A smaller-size magnetoresistive film can be realized, compared to an MRAM using an in-plane magnetization film. Similar to a magnetoresistive film using an in-plane magnetization film, a magnetoresistive film using a perpendicular magnetization film exhibits a relatively low resistance when the magnetization directions of two magnetic layers are parallel to each other, and a relatively high resistance when these magnetization directions are antiparallel. As shown in FIGS. 15A to 15D, a magnetic layer 23 on a nonmagnetic layer 22 is formed as a recording layer, and a magnetic layer 21 below the nonmagnetic layer 22 is as a read layer. The upward magnetization direction of the recording layer is defined as xe2x80x9c1xe2x80x9d, and the downward direction is as xe2x80x9c0xe2x80x9d. As FIGS. 14A to 14D showed, it can compose as a memory element.
Main examples of the perpendicular magnetization film are an alloy film or artificial lattice film made of at least one element selected from the group consisting of rear-earth metals such as Gd, Dy, and Tb and at least one element selected from the group consisting of transition metals such as Co, Fe, and Ni, an artificial lattice film made of a transition metal and noble metal such as Co/Pt, and an alloy film having crystallomagnetic anisotropy in a direction perpendicular to the film surface, such as CoCr. In general, the switching field of a perpendicular magnetization film is larger than that having longitudinal magnetic anisotropy by a transition metal. For example, the switching field of a permalloy as an in-plane magnetization film is about several hundred A/m. The switching field of a Co/Pt artificial lattice film as a perpendicular magnetization film is as very high as about several ten kA/m. An alloy film of a rear-earth metal and transition metal exhibits different apparent magnetization intensities depending on the film composition because the sub-lattice magnetization of the rear-earth metal and that of the transition metal orient antiparallel to each other. Hence, the switching field of this alloy film changes depending on the composition. A GdFe alloy film shows a relatively small switching field among alloy films of rear-earth metals and transition metals. In general, the GdFe alloy film has a switching field of about several thousand A/m around the critical composition at which the squareness ratio of the magnetization curve starts decreasing from 1.
When a sensor, memory, or the like is formed from a magnetoresistive film using a perpendicular magnetization film, the sensor, memory, or the like cannot operate unless a large magnetic field is applied owing to the above-described reason. For example, in the sensor, a stray field must be concentrated on the magnetic layer of the magnetoresistive film. In the memory, a large magnetic field must be generated. A magnetic field applied to a memory is generally generated by supplying a current through a conductor. Especially in a memory used in a portable terminal, supply of a large current is undesirably flowed under restrictions on the power supply capacity. Thus, a conductor for generating a magnetic field must be wound around a memory element formed from a magnetoresistive film. This measure complicates a structure or electrical circuit around the magnetoresistive film, and is difficult to form. This results in low yield and very high cost.
The present invention has been made in consideration of the above situation, and has as its object to provide a magnetoresistive film which reduces the switching field of a perpendicular magnetization film and is easy to form without decreasing the yield or greatly increasing the cost, and a memory requiring only small power consumption.
The above object is achieved by a magnetoresistive film comprising a nonmagnetic film, and a structure in which magnetic films are formed on two sides of the nonmagnetic film, wherein at least one of the magnetic films includes a perpendicular magnetization film, and a magnetic film whose easy axis of magnetization is inclined from a direction perpendicular to a film surface is formed at a position where the magnetic film contacts the perpendicular magnetization film but does not contact the nonmagnetic film.
The above object is also achieved by a memory having a memory element with the magnetoresistive film, comprising means for applying a magnetic field to the magnetoresistive film in a direction perpendicular to a film surface, and means for detecting a resistance of the magnetoresistive film.
The above object is also achieved by the memory wherein a plurality of magnetoresistive films are arranged, and the memory further comprises means for selectively recording information on a desired magnetoresistive film, and means for selectively reading out information recorded on a desired magnetoresistive film.


The invention relates generally to molding forms and, more particularly, to an apparatus for constructing a molding form having an accurately located reference surface that establishes a border for the molded structure.
Molded structures formed along the surface of the ground, such as concrete decks, typically are constructed by preparing a firm bed upon which the deck is to rest. Border defining forms are provided for confining the uncured concrete mixture to a desired border contour. A concrete mixture is poured over the prepared bed to fill the form and the surface of the poured concrete troweled. After the concrete cures to a firm state, the forms are dismantled.
Two types of molding form structures have been used in constructing concrete decks; structures of wood form boards and stakes fastened together by nails, and structures of specially formed metal form boards and stakes held together by rigid metal wedges. The wood form structures are constructed by driving stakes into the ground at intervals along a stake line that follows the desired edge contour of the deck. Then, flexible form boards of wood, commonly referred to as bender boards, are placed against the stakes and fastened thereto by nailing. In most cases, the stakes are displaced by the force of nailing, making it virtually impossible to locate the reference surface of the bender board at the reference line for the border of the deck. In addition to not being able to locate the reference surface precisely, the manner of construction of such wood form structures causes rapid deterioration of the materials used. Repeated nailing weakens the wood bender boards and they frequently break during the assembling and dismantling of the forms. The low number of repeated uses of the wood bender boards and stakes and the consumption of nails is an expense of construction that is becoming increasingly significant with the rising costs of construction materials.
The metal type molding form structure includes a metal form board having a pair of apertured appendages extending perpendicularly from one side of a planar member, the opposite side of the planar member forming the reference surface. A support stake is inserted through apertures of the appendages and a separate rigid metal wedge is driven between the stake and the facing side of the metal form board. Driving the wedge forces the metal form board away from the support stake to cause the stake to bear forcefully against the wall of the apertures whereby the metal form board is held firmly in place relative to the support stake. A substantial force is required to drive the rigid wedge between the stake and the facing side of the form board and, frequently, the wedge galls the side and/or support stake. After many uses of the metal form boards and support stakes, galling often becomes so extensive that the metal form boards and/or support stakes are deteriorated beyond use. Even before the metal form boards and/or support stakes are deteriorated beyond use, galling may deform them to such an extent that accurate location of the reference surface that defines the border of the concrete deck is prevented. Consequently, the metal type molding form structures do not entirely alleviate the shortcomings of the previously described wood type. In addition, it is more costly to manufacture and use the metal form structures than their wood counterparts.
Accordingly, considerable advantage is to be gained by the use of inexpensive molding form components that are not easily damaged by repeated usage. Additional advantages are to be gained by the use of molding form components that permit commonly available bender boards to be used repeatedly.


1. Field of the Invention
The invention relates to a position sensing device and a motor using the same.
2. Description of the Related Art
Sensing devices such as are widely used in motors to detect positions of stators. However, there are several problems with conventional sensing devices: structure of the sensing devices is complex, and connection and fixation between the sensing devices and electric components such as power leads, PCB boards and so on are not firm enough.


Technical Field
The present disclosure relates to memory devices such as a semiconductor memory, and method for testing reliability of memory devices.
Related Art
In general reliability tests on semiconductor memories, a testing device is used to write and read data to and from all regions in a memory array with a known test pattern, and the data written to the memory array by the testing device (expected value) is compared with the data read from memory array by the testing device, so as to check the reliability of the memory array.
In pre-shipment inspection of semiconductor memories, in order to reduce a testing cost, reliability test is generally performed concurrently on multiple semiconductor memories, by connecting multiple semiconductor memories to one testing device and writing and reading data to and from the multiple semiconductor memories with a common test pattern.
With semiconductor memories provided with a pseudo-random number generator for improving security, random number values of pseudo-random numbers are predictable, and thus multiple semiconductor memories can generate an identical pseudo-random number by using a common algorithm. Pre-shipment inspection can therefore be conducted concurrently on multiple semiconductor memories with one testing device, in the same way as on general semiconductor memories.
Random number generators are cryptographic technology employed for a wide variety of uses in many security systems.
Random numbers generated by random number generators are used for, for example, key information in a cryptographic algorithm, or authentication codes for mutual authentication between devices, and are closely related to the security strength of a system and thus highly confidential information.
Random numbers generated by random number generators therefore need to be highly random. At shipment of semiconductor devices provided with a random number generator, a random number test is normally performed to evaluate whether a random number generator generates random numbers that meet a required level.
JP2005-517998A and WO2005/124537A describe a technique to evaluate whether the frequencies of appearance of “0” and “1” in random numbers generated by a random number generator are within an allowable range.


Wireless and voice-over-internet protocol (VoIP) communications are subject to frequent loss of packets as a result of adverse connection conditions. Such lost packets result in clicks and pops or other artifacts being present in the output voice signal at the receiving end of the connection. This degrades the perceived speech quality at the receiving end and may render the speech unrecognizable if the packet loss rate is sufficiently high.
Broadly speaking, two approaches are taken to combat the problem of lost packets. The first approach is the use of transmitter-based recovery techniques. Such techniques include retransmission of lost packets, interleaving the contents of several packets to disperse the effect of packet loss, and addition of error correction coding bits to the transmitted packets such that lost packets can be reconstructed at the receiver. In order to limit the increased bandwidth requirements and delays inherent in these techniques, they are often employed such that packet loss can be recovered if the packet loss rate is low, but not all packet loss can be recovered if the packet loss rate is high. Additionally, some transmitters may not have the capacity to implement transmitter-based recovery techniques.
The second approach taken to combating the problem of lost packets is the use of receiver-based concealment techniques. Such techniques are generally used in addition to transmitter-based recovery techniques to conceal any remaining losses left after the transmitter-based recovery techniques have been employed. Additionally, they may be used in isolation if the transmitter is incapable of implementing transmitter-based recovery techniques. Low complexity receiver-based concealment techniques such as filling in a lost packet with silence, noise, or a repetition of the previous packet are used, but result in a poor quality output voice signal. Regeneration based schemes such as model-based recovery (in which speech on either side of the lost packet is modeled to generate speech for the lost packet) produce a very high quality output voice signal but are highly complex, consume high levels of power and are expensive to implement. In practical situations interpolation-based techniques are preferred. These techniques generate a replacement packet by interpolating parameters from the packets on one or both sides of the lost packet. These techniques are relatively simple to implement and produce an output voice signal of reasonably high quality.
Pitch based waveform substitution is a preferred interpolation-based packet loss recovery technique. The pitch period of the voiced packets on one or both sides of the lost packet is estimated. A waveform of the estimated pitch period is then repeated and used as a substitute for the lost packet. This technique is effective because voice signals appear to be composed of a repeating segment when viewed over short time intervals. Consequently, the pitch period of the lost voice packet will normally be substantially the same as the pitch period of the voice packets on either side of the lost packet.
Many methods are used to estimate the pitch period of a voice signal. Generally speaking, these methods include use of a normalized cross-correlation (NCC) method. Such a method can be expressed mathematically as:
                              N                                                              C                                                                                C              t                                                  (              τ              )                                      =                                            ∑                              n                =                                                      -                    N                                    /                  2                                                                              (                                      N                    /                    2                                    )                                -                1                                                                                x                                                  [                                      t                    +                    n                                    ]                                                                          x                                                  [                                      t                    +                    n                    -                    τ                                    ]                                                                                ∑                                  n                  =                                                            -                      N                                        /                    2                                                                                (                                          N                      /                      2                                        )                                    -                  1                                                                                x                    2                                                                          [                                          t                      +                      n                                        ]                                                                                ∑                                          n                      =                                                                        -                          N                                                /                        2                                                                                (                                                  N                          /                          2                                                )                                            -                      1                                                                                x                      2                                                                                [                                              t                        +                        n                        -                        τ                                            ]                                                                                (                  equation                                                              1                )            where x is the amplitude of the voice signal and t is time. The equation represents a correlation between two segments of the voice signal which are separated by a time τ. Each of the two segments is split up into N samples. The nth sample of the first segment is correlated against the respective nth sample of the other segment.
This equation essentially takes a first segment of a signal (marked A on FIG. 1) and correlates it with each of a number of further segments of the signal (for ease of illustration only three, marked B, C and D, are shown on FIG. 1). Each of these further segments lags the first segment along the time axis by a lag value (τ1 for segment B, ρ2 for segment C). The calculation is carried out over a range of lag values within which the pitch period of the voice signal is expected to be found. The term on the bottom of the fraction in equation 1 is a normalizing factor. The lag value τNCC that maximizes the NCC function represents the time interval between the segment A and the segment with which it is most highly correlated (segment D on FIG. 1). This lag value τNCC is taken to be the pitch period of the signal.
Calculation of the normalized cross-correlation accounts for over 90% of the algorithmic complexity in typical pitch based waveform substitution techniques. Although the complexity level of the calculation is low, it is significant for low-power platforms such as Bluetooth. In order to correctly determine the pitch period of a voice signal, a wide pre-defined pitch period range (range of lag values) is usually used, for example from 2 ms (for a person with a high voice) to 20 ms (for a person with a low voice). For most pitch determination algorithms, the wider the pitch period range used, the higher the computational complexity.
One way to reduce the computational complexity is to reduce the number of calculations that the algorithm computes. U.S. patent application Ser. No. 10/394,118 proposes to reduce the number of calculations by dynamically adapting the time interval between successive segments that are correlated with the first segment. (In the illustration of FIG. 1, the time interval between successive segments B and C is τ2-τ1.) If the correlation decreases, then the time interval to the next segment to be correlated is increased. Conversely, if the correlation increases, then the time interval to the next segment is decreased. This method evaluates the correlation over the same range of pitch periods (for example from 2 ms-20 ms) as methods in which the time interval between successive segments is constant, but advantageously this method is less computationally complex because it carries out fewer calculations by skipping over segments that it considers unlikely to lag the first segment by the pitch period. However, this method is sensitive to local pitch errors. For example, if an error leads to the correlation decreasing just before the pitch period lag value is computed, then the time interval to the next segment may be increased resulting in the algorithm skipping over the pitch period lag value. The accuracy of the estimated pitch period may suffer as a result. Additionally, this method may have difficulty handling voice signals with rapid local pitch variations.
A further problem with pitch based waveform substitution techniques is that they are prone to pitch doubling and pitch halving errors. Pitch halving occurs when the pitch period is determined to be about double its actual length. This may occur, for example with the method described by U.S. Ser. No. 10/394,118 if the peak best correlated with the peak in the first segment were to be skipped over.
Pitch doubling occurs when the pitch period is determined to be about half its actual length. This may happen in the following situation. Voice signals often have two similar peaks per pitch period that are highly correlated with each other. For example, on FIG. 1 the peaks marked 1 and 2 are highly correlated. These could be mistaken for being the same feature present in consecutive pitch periods and hence the time interval between them could be computed to be the estimated pitch period of the signal. Pitch doubling is particularly problematic for packet loss concealment applications because the replacement signal used for the lost packet will be at a non-integer multiple of the pitch period of the lost packet.
Techniques for reducing pitch doubling and pitch halving errors have been proposed, for example frequency domain and statistical techniques and post processing techniques. However these techniques incur additional computational complexity and cost.
There is thus a need for an improved method of estimating the pitch period of a signal that reduces the computational complexity associated with the estimation, and that additionally reduces susceptibility to pitch doubling and pitch halving errors without incurring extra algorithmic complexity.


1. Field of the Invention
The invention relates to a combined power station installation with a gas turbine and a steam turbine, in which the exhaust gases from the gas turbine give up their residual heat to the steam turbine via the working medium flowing in a waste heat boiler, whereby the waste heat boiler consists essentially of an economizer, an evaporator and a superheater and whereby at least one cooling air cooler is provided which is designed as a forced circulation steam generator and is connected on the water side to the economizer of the waste heat boiler.
2. Discussion of Background
Gas turbines of the modern generation and the higher power class operate with very high turbine inlet temperatures, which makes cooling of the combustion chambers, the rotors and the blading unavoidable. For this purpose, highly compressed air is generally extracted at the compressor outlet and, if appropriate, from a lower pressure stage. Because a very high proportion of the compressed air is consumed for the currently conventional premixed combustion, there remains--on the one hand--only a minimum of cooling air for cooling purposes. On the other hand, this air intended for cooling is already very hot because of the compression so that it is desirable that it should be previously cooled. Cooling by means of water injection ("gas quenching") is known for this purpose; in this method, however, the high-quality heat of the cooling air, whose proportion can amount to as much as 20 MW in current machines, is only partially utilized. In consequence, the use of forced circulation steam generators as coolers for recooling seems appropriate, particularly if the gas turbine operates in a combined gas/steam turbine process with waste heat steam generation.
Such a once-through steam generator for cooling highly compressed air of the type mentioned at the beginning is known, in association with a combined gas/steam turbine process, from EP-A-709 561. In this specification, a partial flow of the boiler feed water is extracted either upstream or downstream of the economizer and, after further preheating, evaporation and superheating in the cooler, is fed back into the high pressure superheater of the waste heat boiler. This boiler is designed as a circulating system boiler with drums. In order to avoid the penetration of moisture or water into the steam turbine when the cooler is run wet, the heated water or wet steam is fed into a blow-down tank until the cooler is dry or until defined conditions are stably present at the cooler outlet, for example hot steam with a few degrees Kelvin superheat or wet steam with a humidity of a few percent. In addition to the water losses, this has the consequent disadvantage of a corresponding monitoring and control system.


In recent years, as a battery anticipated to have small size, light weight, and high capacity, a non-aqueous electrolytic solution-based secondary battery such as a lithium ion battery has been proposed and put into practical use.
The lithium ion battery is constituted of a cathode and an anode which allow the reversible insertion and removal of lithium ions, and a non-aqueous electrolyte.
Regarding an anode material for lithium ion batteries, as an anode active material, generally, a lithium-containing metal oxide allowing the reversible insertion and removal of lithium ions such as a carbon-based material or lithium titanate (Li4Ti5O12) is used.
On the other hand, regarding a cathode material for lithium ion batteries, as a cathode active material, generally, a lithium-containing metal oxide allowing the reversible insertion and removal of lithium ions such as lithium iron phosphate (LiFePO4) or an electrode material mixture is used. In addition, the cathode in the lithium ion battery is formed by applying the electrode material mixture to the surface of a metal foil called a current collector.
Compared with secondary batteries of the related art such as lead batteries, nickel-cadmium batteries, and nickel-hydrogen batteries, lithium ion batteries have a lighter weight, a smaller size, and higher energy, and thus are used not only as small-size power supplies but also as large-size stationary emergency power supplies in portable electronic devices such as mobile phones and notebook personal computers.
In addition, recently, studies have been underway regarding the use of lithium ion batteries as high-output power supplies for plug-in hybrid vehicles, hybrid vehicles, and electric power tools, and batteries used as the high-output power supplies are required to have high-speed charge and discharge characteristics.
However, electrode materials including an electrode active material, for example, a lithium phosphate compound allowing the reversible insertion and removal of lithium ions have a problem of low electron conductivity. Therefore, as electrode materials having increased electron conductivity, an electrode material in which particle surfaces of an electrode active material are uniformly coated with a chemically-deposited carbonaceous material, and the current density of the electrode active material is improved (Japanese Laid-open Patent Publication No. 2001-15111), an electrode material including a carbon black complex obtained by conjugating fibrous carbon and carbon black and olivine-type lithium iron phosphate (Japanese Laid-open Patent Publication No. 2011-108522), and the like have been proposed.


As electronic components continue to advance and are made more powerful, they tend to produce more and more undesirable heat which is preferably removed. This has created a growing need for higher capacity cooling systems to remove heat from all or a portion of the electronic components.
As the trend is to make electronic components more powerful, there is also an increasing push to reduce the size of the electronic components, and the packaging of the electronic components. The smaller components and packaging makes the removal of the unwanted heat more difficult.
In some applications, direct impingement thin-film evaporative spray cooling is preferred in order to provide sufficient cooling, whereas in other applications spray cooling is desired to reduce the overall package or housing size even though the required cooling capability is not as high. This creates a situation in which transverse narrow gap evaporative spray cooling is advantageous if it can be done to an acceptable efficiency level.
Narrow gap evaporative spray cooling will preferably provide or spray the coolant from a transverse side of the surface to be cooled (or the surface from which heat is to be transferred). Proper cooling is preferably achieved if a thin liquid film is maintained over the device or electronic component to be cooled, thereby facilitating evaporation of the coolant as heat is transferred from the electronic component. If there is too little flow or coverage of coolant, the liquid layer covering the electronic component will dry out and cause the component to overheat because vapor forced convection will not typically provide sufficient heat transfer. If the flow of coolant to the component is too great, the device will become flooded and may produce hot spots, insufficient cooling and/or failure, because the vapor created from the evaporation may become trapped between the excessive fluid and the impingement surface of the electronic component. This will normally reduce the cooling efficiency. Vapor generated at the surface of the component which receives too much coolant cannot escape effectively and could result in a boiling heat transfer failure mode generally referred to as burnout.
Even when the volume flux of coolant is properly matched to the heat flux of the device, the excess fluid sprayed within a cavity must generally be managed by the method described in U.S. Pat. No. 5,220,804 to prevent the overflow from adjacent components from interfering and causing flooding type failure conditions.
It is therefore an objective of some embodiments of this invention to provide a narrow gap, thin-film, evaporative spray cooling system for cooling one or more electronic components in the narrow gap.
It is also an objective of some embodiments of this invention to provide a narrow gap evaporative spray cooling system which improves the cooling characteristics of the system, especially at the entry end of the cooling channel or conduit, and/or reduces the pressure gradient above the surface from which heat is to be transferred.
It is also an objective of some embodiments of this invention to provide a housing system which provides improved re-circulation of the vapor for re-introduction of the vapor into the cooling conduit.
It is an objective of some embodiments of this invention to provide a re-circulation system which reduces pooling of the liquid portion of the coolant at or near the exit end of the cooling conduit.


The present invention relates to a plate-like plant carrier for purposes of cultivating layers, i.e. plants in their very early growth, and to have seeds germinate; and particularly the invention relates to a plant growth structure on or as part of plant tables in horticulture, or to be used directly in the ground, or in flower boxes or other open growth systems or in closed systems (glass houses), all for cultivating plants in their early stages.
It is known to cultivate plants in boxes, in flats, i.e. in flat boxes made of wood or synthetic material. The flat configuration may also be the result of a small, usually square or rectangularly-shaped and usually plastic flower boxes. What happens to the boxes after planting has obtained is often not deemed a factor, but for reasons of ecology it is. Reference is not made here to the situation of the direct re-use of the boxes after emptying them for planting; of course such boxes can be used over and over again for the same purpose. But presently it is of interest here are that there are situations in which, for some reason, it is not desirable to disturb the seedlings or plants but to leave the container in place, i.e. the plants are just planted in their container. This may readily result in ecological problems.
The principle of containing a plant and root system in a small, box-like container carries with it the following problem: a certain amount of water retention is required so that the root system and surrounding soil will not dry out too quickly. On the other hand, if insufficient drainage is provided, then the plant system may begin to rot or be prone to other forms of sickness.
It is also known to use very finely ground peat and to press a certain portion into a rod-like configuration. This peat rod is then surrounded by and held in a net made of synthetic material which is configured in this case in that it can deform elastically. Such a rod or strand is then cut into a suitable length and is used for individual cultivating and planting of seeds and small plants. If the pressed strand is watered it will swell as the surrounding synthetic net expands. The finely ground peat, however, has a very small pore volume when compressed, which has an effect on the growth of the plant. In addition, any capillary action is rather poor in compressed peat. Hence, such finally ground peat is a poor agent as far as rewetting is concerned.
Certain greening flats are known, for example, for use as roof covers or as embankment covers. In the latter case, the task is to have the roots of the plants traverse their container as fast as possible so that the roots physically combine with the underlying soil. In this way one makes sure that the entire arrangement is rapidly and so-to-speak naturally anchored to the ground.
On the other hand, roof covers are usually made of mats which contain both plant food and grass seed. These mats are constructed such that the cover on which the mat rests should not receive much moisture, that is, the mat is comprised, for example, of a synthetic layer upon which are deposited layers of nutrients and other plant food to enable the grass to germinate and grow. These mats are constructed for exactly that particular purpose, namely, for providing a green cover on a roof, and these rather highly, specialized mats are usually not useful in a different environment.


The ultimate goal for a NVSRAM memory design is to work like a regular SRAM memory but with a non-volatilability to store the data after power is removed. This is called the Store operation. There are three kinds of Store operations and each time is performed to write SRAM cell's data into each corresponding Flash cell.
In a traditional 12T NVSRAM cell, the Write operation is a 2-step operation that uses Erase as a first step to either increase or decrease Flash cell Vt and is followed Program as a second step to conversely decrease and increase Flash cell's Vt to get the final desired Vts of Vt1 (≧2V) and Vt0 (≦−2V) on a single Flash cell. As a result, for traditional 12T NVSRAM cells a Recall operation is based on a method to detect a wide ΔVt (Vt1−Vt0=4V) between one paired flash transistors. But after a long P/E endurance cycle, the distance of the gap of ΔVt of Erase and Program Vt becomes smaller, thus the 12T NVSRAM cell operation becomes critical.
Therefore, an improved NVSRAM cell design with reduced cell size and proper write operation and recall operation are desired and become objectives of the present invention.


(a) Field of the Invention
This invention generally relates to an internal combustion engine that uses rotors or turbines to convert energy released from combustion to shaft power or mechanical output. More particularly, but not by way of limitation, to a rotary motor that includes at least one combustion chamber that delivers the products of combustion in a controlled manner to a turbine or rotor.
(b) Discussion of Known Art
The advantages of a rotary type motor have long been recognized. However, the development of a motor that is able to reliably deliver power harnessed from combustion has seen few successful solutions. The need or absence of such an engine has been particularly acute in the area of smaller turbines where the flow of gasses through the turbine must be carefully controlled in order to prevent damage to the surrounding areas from the exhaust.
The use of a separate combustion chamber, which allows the generation of a working fluid is found in the field of steam turbines, where the steam that is used as the working fluid that moves the turbine is generated in a separate boiler that feeds steam to the turbine. This type of system takes advantage of the ease with which steam pressure can be controlled to deliver a desired flow rate of steam to the turbine. Thus, the steam turbine model provides a good model for applications where a working fluid such as steam can be released at a controlled rate. However, this model has proven to be inappropriate for applications where the turbine is to be rotated by the products of combustion of a fuel and oxidant mixture, for example.
Many known turbine applications that use products of combustion in order to turn the blades of a turbine use a series of turbines that harvest the power released from the rapid expansion from combustion to harvest the needed power to compress the fuel and oxidant mixture and provide power to carry out useful work. Thus, these systems employ a set of axially positioned turbine components that depend on high speed rotation of the components, and very high flow rates of the gases used to power the turbines, in order to provide sustained combustion and rotation of the compressor and power generation components.
Furthermore, it is well recognized that turbines offer significant advantages over reciprocating engines, particularly in applications where high revolutions per minute (RPMs) are required. However, it has not been practicable to provide a small turbine that can be used in, for example, automotive applications. A significant drawback to the use of turbines in these applications is the high flow rate of gasses generated and discharged during the operation of the turbine. The temperature and flow rate of the exhaust gases delivered from such a turbine create the possibility of causing serious injury to people and property in the vicinity of the exhaust from the vehicle.
Thus, there remains a need for a turbine based engine that can be driven by gases produced from internal combustion, and that permits a highly controlled flow of these gases through the turbine.
There remains a need for a turbine base engine that uses at least one turbine to harvest the power released upon combustion, and which allows control of the combustion and delivery of the products of combustion to the turbine.
It has been discovered that the problems left unanswered by known art are solve by providing a turbine based engine that includes:
a mixture chamber;
a combustion chamber;
a stationary flow control barrier; and
a turbine. The stationary flow control barrier is located between the combustion chamber and the turbine. It has been discovered that this arrangement allows the system to provide precisely measured and mixed fuel and oxidant mixtures to the mixture chamber where it is burned to produce the expandable gas product that will be expanded through the turbine to turn the turbine.
According to a highly preferred embodiment of the invention the stationary flow control barrier consists of a gas flow control plate that includes ducts that permit gases to flow from the combustion chamber towards the turbine. In a highly preferred embodiment of the invention, these ducts have a tapered or nozzle shaped contour, starting as an aperture of a first dimension near the combustion chamber and progressing to a second, smaller dimension near the turbine. This reduction in the size of the ducts will have the effect of accelerating the flow of the products of combustion as it progresses towards the turbine.
It is further contemplated that the fuel and oxidant mixture will be delivered to the combustion chamber by way of valves that control the flow of mixture gases into the combustion chamber. It is contemplated that these valves may control the flow of a fuel and oxidant mixture or the flow of at least one of the components for the mixture and the remaining components for the mixture provided by of an injector or other delivery device.
According to a highly preferred example of the invention, a generally symmetrical arrangement is provided. In this arrangement an expeller device is position along a place of symmetry for the system. Thus, a turbine is positioned on each side of the expeller. The turbines will allow expansion towards the expeller, and thus allow mounting of the expeller and turbines along a single shaft between a pair of mixture chambers, combustion chambers, and flow control barriers.
It is further contemplated that these examples may include gas flow control systems that are indexed from the shaft that supports the turbines. It is contemplated that these systems may include cams, markers or other triggering mechanisms that may be used to control a signal that is used to control the delivery of the gasses needed for combustion.
Thus, it should also be understood that while the above and other advantages and results of the present invention will become apparent to those skilled in the art from the following detailed description and accompanying drawings, showing the contemplated novel construction, combinations and elements as herein described, and more particularly defined by the appended claims, it should be clearly understood that changes in the precise embodiments of the herein disclosed invention are meant to be included within the scope of the claims, except insofar as they may be precluded by the prior art.


1. Field of the Invention
The invention relates to an air purification system. More specifically, the invention relates to such a system which includes an ozone generator means for producing ozone to react with impurities in the air, and which system also includes a high power corona generating device for removing ozone from the purified air.
The invention also relates to a high power corona generating device, and to an air purification system using only the high power corona generating device.
2. Description of Prior Art
Low power ozone generators are now being used as air purifiers to treat air in a variety of commercial applications where air quality is unsatisfactory and where special air treatment is desired. Ozone in present purifiers is created when air is drawn through an electrical corona formed over generator plates at high voltage. Such purifiers rely for their effect on adding ozone to the air and allowing natural diffusion to spread the air and ozone through the area to be treated. The concentration of ozone in atmospheres being treated by present purifiers is low and therefore provides sub-optimal results. Some of the disadvantages of the above-described systems are as follows:
Air throughput into the machine is low so that only a very insignificant amount of air treatment occurs within the machine.
Health regulations require that the concentration of ozone in the ambient air of the workplace should not exceed 50-100 parts per billion. Since this low concentration has very limited air purifying capability, this places a very serious constraint on the efficiency and power of present purifiers used in the manner as above-described.
Air purification systems are also described in U.S. Pat. No. 4,451,435, Holter et al, May 29, 1984, U.S. Pat. No. 3,949,055, Schneider et al, Apr. 6, 1976, and U.S. Pat. No. 4,101,296, Lowther, July 18, 1978.
The '435 Patent illustrates, in FIG. 3 thereof, a system including an ozonizer (ozone generator) 11 and beds of sorption masses and catalyst masses 1-9. In accordance with the '435 Patent, the air purification process requires the application of heat and the subsequent application of cooling to remove impurities from the air. Additionally, the apparatus of the '435 Patent does not include any means for decomposing ozone remaining in the air.
The '055 Patent teaches the use of an aqueous solution of ozone to remove gaseous or smoke-like substances from the air in industrial areas. The '296 Patent teaches an ozone decomposition system. In neither case could large volumes of air be treated economically.
A further air purifying system is illustrated in U.S. Pat. No. 4,049,400, Bennett et al, Sept. 20, 1977. The system as taught by Bennett et al includes an ozone generator and an electrostatic filter. This again does not include any means for decomposing ozone remaining in the air.
It is also known that certain levels of ozone in the atmosphere can be harmful to people, and that even relatively low levels of ozone can have a corrosive nature. Accordingly, air purifying systems which use ozonators to purify the air but which leave the ozone in the air to be spread throughout the environment of the system could be potentially unsatisfactory.
Ozone generators, per se, are also taught in the following patents which constitutes only a partial list of such teachings. U.S. Pat. No. 4,666,679, Masuda et al, May 19, 1987, U.S. Pat. No. 3,903,426, Lowther, Sept. 2, 1975, U.S. Pat. No. 1,169,825, Hoofnagle, Feb. 1, 1916, U.S. Pat. No. 2,822,327, Hammesfahr et al, Feb. 4, 1958, U.S. Pat. No. 3,607,709, Rice, Sept. 21, 1971, U.S. Pat. No. 3,838,290, Crooks, Sept. 24, 1974, U.S. Pat. No. 4,650,648, Beer et al, Mar. 17, 1987, and U.S. Pat. No. 4,690,803, Hirth, Sept. 1, 1987.