Process for manufacturing temperature-sensitive polymers utilizing a heat transfer fluid comprising a hydrocarbon fluid selected from aliphatic hydrocarbons, alicyclic hydrocarbons, aliphatic- or alicyclic-substituted aromatic hydrocarbons, or mixtures thereof, the hydrocarbon fluid having a boiling point from 220° C. to 250° C. and a melting point less than 40° C., and temperature-sensitive polymer articles produced therefrom.

The present invention relates to a process for the manufacture of temperature-sensitive polymers utilizing a heat transfer fluid comprising a hydrocarbon fluid selected from aliphatic hydrocarbons, alicyclic hydrocarbons, aliphatic- or alicyclic-substituted aromatic hydrocarbons, or mixtures thereof, the hydrocarbon fluid having a boiling point from 220° C. to 250° C. and a melting point less than 40° C. The present invention further relates to a process for manufacturing temperature-sensitive polymers utilizing a heat transfer fluid comprising a fluid selected from phenylcyclohexane (also known as cyclohexylbenzene), bicyclohexane (also known as bicyclohexyl), hydrogenated biphenyl having a level of hydrogenation between phenylcyclohexane and bicyclohexane, or mixtures thereof. The present invention further relates to plastic products made in accordance with the inventive process.
Heat transfer fluids, which can also be termed "heat carriers", are used to transfer heat energy between systems of different temperatures. Heat transfer fluids generally are eminently well-known and have been used commercially for a long time. The large majority of commercial transfer fluids, including Therminol®VP-1, (Solutia Inc.), Diphyl®DT (Bayer A.G.), Dowtherm®A (Dow Chemical) and Therm® S300 (Nippon Steel), all consist of a binary system of about 26% biphenyl and 74% diphenyloxide. Such heat transfer fluids are characterized by a boiling point of about 256° C. at atmospheric pressure and, in addition, exhibit desirable in-use properties including oxidative and thermal stability, good heat transfer properties, virtually no equipment corrosion and good economy. Irrespective of such benefits, boiling temperatures of commercial heat transfer fluids, generally above 250° C., are too high for the manufacture, including extrusion, of temperature-sensitive polymers, such as Nylon 6 and PTT (polytrimethylene terephthalate), and can lead to difficulties in the processing of the polymer and, consequently, undesirably altered in-use properties of the extruded article. In fact, a boiling point difference exceeding about 2° C. can lead to a different crystallization behavior of the polymer in the extruded article and thus yield an article exhibiting modified bulk and surface characteristics. The problem had been known for a long time and no completely satisfactory commercially-viable approaches, e.g. heat transfer fluids meeting essentially all the desired performance properties, for eliminating the difficulties have been made available up to now.
Polymer manufacturing temperatures exceeding about 245° C., can be detrimental to the quality of the extruded article made from temperature-sensitive polymers. The lowering and control of the boiling temperature of heat transfer fluids was normally achieved by applying partial vacuum. However, the use of reduced pressures requires supplementary equipment and, more importantly, selected pressures can, and normally will, vary considerably during industrial polymer manufacturing operations to thus yield deficient polymer articles. The prior art relating to the manufacture of extruded polymer articles, and the use of heat transfer fluids in such an arrangement, is well-known in the relevant technical community. U.S. Pat. No. 3,925,013 teaches the use of binary and ternary eutectic solvent mixtures for use in disperse dye carrier formulations to improve handling properties at ambient temperatures. A binary mixture of from 55–10% biphenyl and 30–45% naphthalene was found to possess a suitably lowered crystallization point so that dye carrier properties become easier. U.S. Pat. No. 5,397,491 describes heat transfer fluids, containing substituted diphenyl, exhibiting improved thermal stability at temperatures exceeding 300° C. JP-A-9145994 describes heat transfer fluids based on mixtures of alkyl naphthalenes and alkylbiphenyls, particularly combinations of diethyl biphenyl and diisopropyl naphthalene. WO 8907634 pertains to heat transfer agents consisting particularly of diphenylethers of terphenyl, biphenyldiphenyl ethers and naphthalene diphenylethers. JP-A-6968314 discloses heat transfer agents containing mixtures of biphenyl and/or naphthalene and diphenylether and terphenyl. WO 98 50483 concerns heat transfer fluids exhibiting favorable thermal stability comprising a mixture of tetrahydro(phenylethyl)naphthalene and dibenzyl toluene.
PCT Application no. PCT/EP00/12077 discloses a process for manufacture of temperature-sensitive polymers using a heat transfer fluid consisting essentially of a binary mixture of biphenyl and naphthalene in a weight ratio of 65:35 to 55:45. While this fluid is a stable and efficient heat transfer fluid with a boiling point below 245° C., it is desirable to provide a heat transfer fluid that meets more of the desired heat transfer fluid properties.
It is desirable to provide a heat transfer fluid useful for the manufacture of temperature-sensitive polymers having a lower boiling point and lower melting point than currently available heat transfer fluids, which preferably also has improved environmental, safety and health properties.
It has now been discovered that a heat transfer fluid selected from a hydrocarbon fluid selected from aliphatic hydrocarbons, alicyclic hydrocarbons, aliphatic- or alicyclic-substituted aromatic hydrocarbons, or mixtures thereof, the hydrocarbon fluid having a boiling point from 220° C. to 250° C. and a melting point less than 40° C., achieves these desired properties, and meets the demands for use in the production of temperature-sensitive polymers.
It has now been further discovered that a preferred heat transfer fluid selected from phenylcyclohexane, bicyclohexane, hydrogenated biphenyl having a level of hydrogenation between phenylcyclohexane and bicyclohexane, or mixtures thereof achieves these desired properties, and meets the demands for use in the production of temperature-sensitive polymers.

Process for the manufacture of temperature-sensitive polymers


The present invention provides a system and method for storing re-synchronization, error correction and/or error detection data within an existing communication protocol, while still maintaining full compliances to a standard, such as the MPEG-2 AAC standard. By doing so, data information can still be passed from an encoder to a decoder via a channel using an existing and well known standard transport protocol. However, the existing well known transport protocol can now include the data necessary for synchronization of the decoder to the received raw data, along with error detection and error correction by the decoder.

1. Field of the Invention
The invention relates to a system and method for representing compressed information within a data stream.
2. Description of Related Art
Currently, numerous standards exist for encoding data for transmission across a channel to a receiver (decoder). For example, the International Standard ISO/IEC 13818-7, Advanced Audio Coding, also known as MPEG-2 AAC, specifies a syntax for representing compressed audio signals which are suitable for transmission over limited bandwidth channels. The same syntax with one minor backwards compatible extension is International Standard ISO/IEC 14496-3, also known as MPEG-4 audio. Because these standards typically address transmission of the compressed data over bit-serial channels (e.g., a radio modem channel) the compressed format is often referred to as a bitstream, although the standard is equally valid for other transmissions or storage formats.
Current standards for representing compressed data in a data stream may not support re-synchronization of the bitstream and a decoder. Additionally, current standards may not provide for any explicit form of error detection, error control, or error recovery. For example with existing protocols, such as MPEG-2 AAC, it is necessary for the decoder to know the beginning of a received stream of raw data in order for the decoder to be able to decode the raw data. While information for synchronization of a decoder to a raw data stream is available in applications, such as receiving a computer file from a hard drive or the like, in many applications the synchronization information is not available. For example, in satellite or digital radio communications, the decoder can begin to receive the signal at any point during the signal transmission. Accordingly, the decoder needs to be able to synchronize with the signal in order to properly decode the signal.
One solution to resolving the synchronization problem, is to provide a separate synchronization channel in parallel to the data channel. An example of this technique could include having a decoder receive a first data stream containing video data, a second data stream containing audio data and a third data stream containing synchronization data. Accordingly, the decoder may then use the synchronization data to decode and synchronize with both the audio and video data. However, such systems can become very complicated since the decoder must receive and process numerous different signals.
Accordingly, there exists a need for providing a method for representing compressed information which provides for re-synchronization along with error detection and error correction.

This patent is subject to a terminal disclaimer.

System and method for representing compressed information


A method and apparatus that for monitoring the physiological state of nutrition of an individual and adaptively analyze that data input to anticipate the individual's nutritional needs. A satiety meter may be employed to analyze a user's profile including nutritional state and determine when and how much a user should consume to prevent the onset of hunger and communicate is to a decision engine. The decision engine may generate and communicate a message to the user via the client device to prescribe prophylactic intake of nutrition to the individual prior to the onset of hunger based on the user's nutrition plan and/or regimen.

In the United States, approximately 66% of the adult population (≥20 years) has been classified as either overweight or obese, and many health problems and chronic diseases can be partially or completely attributed to these two factors. Ogden, C. L., Carroll, M. D., Curtin, L. R., McDowell, M. A., Tabak, C. J., Flegal, K. M. Prevalence of overweight and obesity in the United States, 1999-2004. JAMA. 2006 Apr. 5; 295(13):1549-55. For example, obesity is implicated in many types of cardiovascular disease (CVD), which represents the leading cause of mortality (871,517 deaths in 2004) in the United States. Rosamond et al., American Heart Association Statistics Committee and Stroke Statistics Subcommittee; Heart disease and stroke statistics—2007 update: a report from the American Heart Association Statistics Committee and Stroke Statistics Subcommittee. Circulation. 2007 Feb. 6; 115(5):e69-171. Additionally, research indicates that obesity is implicated in as many as one third of all cancers, which represent the second leading cause of mortality in the United States (American Cancer Society). Wolk, A., Gridley, G., Svensson, M., Nyren, O., McLaughlin, J. K., Fraumeni, J. F., Adam, H. O. A prospective study of obesity and cancer risk (Sweden). Cancer Causes Control. 2001 January; 12(1):13-21. Furthermore, obesity is implicated in many chronic diseases such as hypertension and Type 2 diabetes. Burton, B. T., Foster, W. R., Hirsch, J., Van Itallie, T. B. Health implications of obesity: an NIH Consensus Development Conference. Int J Obes. 1985; 9(3):155-70. Obesity related diseases have a significant monetary impact on the world health system: CVD alone was estimated to cost the United States health care system $431.8 billion in 2004. Rosamond et al., 2007.
Since the majority of these disease states are causally linked to obesity, they may be either mitigated or prevented by simply altering the diet, nutrition and appetite of an affected individual. The concept of weight loss by diet regimen is well known in the art. Prior art systems of weight management can be broadly divided into several types.
One type essentially tells an individual what to eat. For example, U.S. Pat. No. 5,683,251 provides a method for teaching children about various food groups so that they may learn about proper nutrition. An approach designed for adults is presented in U.S. Pat. No. 6,336,136, which provides a computer program that determines a weight reduction program (i.e. choosing appropriate meals) for an individual based on a variety of data that can be input by the user.
Another type consists of systems of prepackaged food that give an individual specific food to eat, for example, as mentioned in U.S. Pat. Nos. 6,102,706, 5,994,295, and U.S. Publication No. 20050118233.
Another type assists an individual in maintaining a previously established diet plan. For example, U.S. Publication No. 20070208593 provides a computer based system that accepts user input about current eating habits and provides feedback and encouragement about the user's progress towards defined weight loss goals. Similarly, U.S. Publication No. 20060058586 provides a computer based program that monitors an individual's diet over time, and then suggests alternative dietary consumption that is in line with the individual's goals. U.S. Publication No.: 20070135266 provides a computer based system that accepts user input about current eating habits and/or exercise level and provides feedback and encouragement to the user about what foods to eat and not to eat. Further, CA Patent No. 514,822 teaches a devices that monitors caloric intake based on a chart of food group listings and helps the user to follow an established diet plan.
U.S. Publication No. 20050096637 (hereafter the '637 publication) references several different medical device/sensors that measure physiological parameters that vary with food intake (e.g. core body temperature, glucose, trans-abdominal impedance, electrical activity of the gastrointestinal tract, and physical motion). The '637 publication discloses a system comprising:                "a sensor to sense a physiological parameter of a patient that changes as a function of a quantity of food consumed by a patient; a processor to estimate the quantity of food consumed by the patient as a function of the sensed physiological parameter and to generate a control signal to control a drug delivery system as a function of the estimation; and the drug delivery system configured to deliver a drug to a body of the patient in response to the control signal."The '637 publication describes a reactive system that responds to a change in food consumption by delivering an appropriate drug. The sensors of the '637 publication are not configured in a system that addresses nutritional states relevant to diet/weight-loss regimens. Furthermore, the system of the '637 publication does not in any way address other nutrition or appetite related goals.
U.S. Pat. No. 5,673,691 (hereafter the '691 patent) discloses a hand-held micro-computer weight control device that is used by a single user. The device in the '691 patent accepts user input of physical characteristics and goals to be reached. The device in the '691 patent monitors the user's physical characteristics, exercise, and caloric intake and provides feedback regarding the user's progress and may adjust the user's program in response to the user's adherence to the goals, such as by lowering or raising the caloric intake recommended to the user. The '691 patent also incorporates behavior modification procedures such as stimulus control, prompting, shaping, goal setting, and feedback into a weight loss program designed to change the nutrition and exercise habits of the user. The device generates visual and audio prompts to signify times to eat, drink water and exercise, prescribes what to eat and in what quantities, and duration of exercise. The affect of the '691 patent's program is that by following the prompts of the device, the user develops a structured routine of eating meals at consistent times, exercising three times per week, weighing daily, and drinking water at regular intervals throughout the day.
The '691 patent discloses a single user device that prompts a user to eat, drink water and exercise at specific times to enable the user to develop a structured and consistent routine. The '691 patent does not disclose monitoring the physiological state of nutrition of an individual and adaptively analyzing that data to anticipate the individual's nutritional needs and prompt the individual to eat and/or drink prior to the onset of hunger. The '691 patent does not use physiological or behavioral and attitudinal data, rather it uses physical data such as age, height, and weight to monitor the user. The '691 patent involves a single user device and therefore does not use third party data that may be adapted and incorporated into the user's experience.
Generally, the prior art systems and/or methods are based on general rules (i.e. total calorie intake or % carbohydrate intake) and fail to account for variations in individual physiology, nor do they consider concurrent physiological requirements, behavioral and/or attitudinal factors relating to the individual. They do not monitor what the individual is eating on a real-time basis. They only provide limited instructive feedback to the individual based on generally static information and parameters. They do not consider successes or modify rules based on successes of rules over time based on information from the individual or like individuals. Furthermore and very significantly, they do not preemptively prescribe nutritional measures or instruction that is tailored to an individual's physiology and demands as a prophylactic to overeating and in turn poor health/nutritional behavior.

Method and apparatus to monitor, analyze and optimize physiological state of nutrition


A semiconductor device is fabricated while mitigating conductive void formation in metallization layers. A substrate is provided. A first dielectric layer is formed over the substrate. A conductive trench is formed within the first dielectric layer. An etch stop layer is formed over the first dielectric layer. A second dielectric layer is formed over/on the etch stop layer. A resist mask is formed over the device and via openings are etched in the second dielectric layer. The resist mask is removed by an ash process. A clean process is performed that mitigates/reduces surface charge on exposed portions of the etch stop layer. Additional surface charge reduction techniques are employed. The via openings are filled with a conductive material and a planarization process is performed to remove excess fill material.

Integrated circuits and semiconductor devices are fabricated by performing a number of fabrication processes that form various components and regions, such as source/drain regions, gate structures, isolation regions, and the like. One set of structures formed and/or present in semiconductor devices are metallization layers, which provide electrical connections between various components within the devices and external connections.
The metallization layers typically comprise trenches and vias formed in single or dual damascene fabrication processes. The trenches and vias are comprised of conductive materials and are separated by insulating layers comprised of dielectric material to, for example, mitigate crosstalk between various layers. The trenches and vias form interconnects or pathways through the dielectric material.
The yield and reliability of fabricated semiconductor devices is dependent upon the single or dual damascene fabrication processes employed to form the metallization layers. Defects in the metallization layers can be formed or introduced during the damascene fabrication processes and degrade the overall yield and reliability of semiconductor devices.
One type of defect that can be found in metallization layers is a punch thru defect, which is a region of missing copper in a metal level that is undesirably removed. The punch thru defects can degrade device performance by, for example, increasing resistance or preventing electrical connections.

Reduction of punch-thru defects in damascene processing


The major objective is to provide a fluorocarbon film wherein fine voids are formed by a step (SA1) for introducing a mixed gas containing a first carbon fluoride gas and a second carbon fluoride gas on a substrate placed inside a chamber, and depositing a fluorocarbon film on the substrate; and a step (SA2) for forming voids in the fluorocarbon film by selectively removing volatile components contained in the fluorocarbon film are included and especially in the step (SA2) for forming voids, it is preferable to include a step for cleaning the fluorocarbon film with a supercritical fluid.

Conventionally, although silicon oxide (SiO2) films have been widely used as interlayer insulation films for semiconductor devices, signal delay caused by the electrostatic capacity between wirings or electrostatic capacity between layers and wiring resistance has increased with miniaturization. Therefore, there is a need for a technique for forming an insulation film having a specific inductive capacity lower than that of a silicon oxide film (hereafter referred to as "low-dielectric-constant film").
An amorphous fluorinated carbon obtained by depositing carbon fluoride gas (hereafter simply referred to as "fluorocarbon film" in this specification) has attracted attention because of extremely low specific inductive capacity among various low-dielectric-constant films (refer to documents described below).
[Non-Patent Document 1] Tatsuru SHIRAFUJI et. al., Jpn. J. Appl. Phys., Vol. 42 (2003), pp. 4504-4509
[Patent Document 1] Japanese Patent Application Laid-Open No. 2000-332001
[Patent Document 2] Japanese Patent Application Laid-Open No. 9-237783 [Patent Document 3] WO99/28963

Fluorocarbon film and method for forming same


A torque member has thread holes for attaching itself to a vehicle body and L-shaped rails for supporting inner and outer brake pads in the circumferential direction of a disc rotor, so as to allow the brake pads to be displaced in the axial direction of the disc rotor. Those of the L-shaped rails which face one another in the axial direction of the disc rotor are cross-linked by two bridge parts at their outer ends as viewed in the radial direction of the disc rotor. A corresponding caliper bridge part fits between the two bridge parts. The L-shaped rails facing in the circumferential direction of the disc rotor are connected together at their inner ends as viewed in the radial direction of the disc rotor by beams.

1. Field of the Invention
The present invention relates to a floating caliper type disc brake device suitably adapted for heavy vehicles such as a commercial vehicle, and in particular to a torque member which forms an essential part of the disc brake device.
2. Description of Related Art
A disc brake device clamps a disc rotor which is rotated together with a rotating body to be braked, on both sides of the disc rotor in the axial direction of the latter, with a pair of brake pads so as to brake the disc rotor.
Furthermore, the pair of brake pads are circumferentially held in brake pad supporting parts of a torque member so as to be displaceable in the axial direction of the disc rotor while the torque member is attached to a vehicle body at its one side in the axial direction of the disc rotor so as to receive a torque which is transmitted thereto from the disc rotor through the brake pad supporting parts upon braking.
It is noted that the pressing of the pair of brake pads against the disc rotor is carried out by a caliper which is supported on the above-mentioned torque member so as to be displaceable in the axial direction of the disc rotor in the case of a floating caliper type disc brake device.
By the way, in the case of a floating caliper type disc brake device for a heavy vehicle, the energy to be braked is large. Accordingly, a torque transmitted to the torque member from the disc rotor through the brake pad supporting parts is also large, so that it is required to enhance the rigidity of the torque member.
In order to enhance the rigidity, it has been conventionally proposed, as disclosed, for example, in Japanese Patent Laid-Open Publication No. 55-44,200, to take the following countermeasure for the torque member.
That is, as shown in FIG. 5, a torque member b attached at its part a to the vehicle body and supporting a caliper which is not shown and which is floatable in the axial direction of a disc rotor by means of a pin guide mechanism planted in a part c, includes brake pad supporting parts d and bridge parts e each of which couples two of the brake pad supporting parts d opposed in the axial direction of the disc rotor, and which are connected to together by a cross-linking part f laid along the outer periphery of the disc rotor, thereby the above-mentioned counter measure for the torque member b can be made.
The brake pad supporting parts d on the outer side remote from the vehicle attached side, is subjected to a force indicated by arrow .alpha. when a torque is transmitted to the brake pad supporting parts d from the disc rotor upon braking, and this force .alpha. causes the brake pad supporting parts d to be displaced in the rotating direction of the disc rotor.
Since the bridge parts e are coupled therebetween with the cross-linking part f in the above-mentioned conventional torque member b, the above-mentioned outer side brake pad supporting parts d can be restrained at their outer end parts in the radial direction of the disc rotor from being displaced even by the force .alpha..
However, the inner end parts of the outer side brake pad supporting parts d in the radial direction of the disc rotor is not given with a sufficient restraining force even by the cross-linking part f, and accordingly, they are displaced by the force .alpha. in the same direction as that of the latter, that is, in the rotating direction of the disc rotor, and further, a mouth opening deformation in a direction indicated by arrow .beta. is unavoidable.
Thus, the conventional torque member b is likely to incline the outer brake pads, causing uneven wear of the outer brake pads.
Further, since the cross-linking part f is laid along the outer periphery of the disc rotor, it has been proposed that it degrades the cooling ability of the disc rotor, and further, the assembling ability of the disc brake device is deteriorated due to the following reasons.
That is, when the disc brake assembly is to be attached to the chassis of a vehicle body, opposite brake pads are spaced from one another by an elastic spacer having a thickness larger than that of the disc rotor and previously interposed between the opposite brake pads, and in this condition, the disc brake assembly is simply fitted from above onto the disc rotor which has been incorporated in the chassis, so as to expel the elastic spacer between the opposite pads by the disc rotor. Thus, it is usual to enhance the assembling ability of the disc brake assembly to the chassis.
However, in the conventional disc brake device, since the cross-linking part f is laid along the outer periphery of the disc rotor, the above-mentioned elastic spacer cannot be removed from the space between the brake pads. Accordingly, the above-mentioned assembling process cannot be used, and as a result the disc brake device is more difficult to assemble.


A container can include a body having an opening, a lid for selectively covering the opening, and a lock system for securing the lid. The lock system can include a limiter slidably mounted on a pivot pin between first and second latch members and configured to engage and control rotation of the first and second latch members. The limiter can be weighted such that when the container is upright the limiter is biased by gravity towards a pivot pin when the first and second latch members engage a lock pin and prevent the first and second latch members from disengaging the lock pin.

When containers such as trash or compost bins contain food scraps, animals may be attracted and try to gain access to the container. Accordingly, it is desirable to provide such containers with lockable lids to inhibit access by animals. However, such containers must also be readily openable for filling by users and automatically open for dumping by automated waste collection.
The inventors have determined a need for improved containers with lockable lids.

Container with gravity releasable locking lids


There are provided a DC/DC converter and a display device. The DC/DC converter includes: an inductor connected to an input terminal; a switching element connected between the inductor and the earth; a diode connected between the inductor and an output terminal; a capacitor connected between the output terminal and the earth; a feedback circuit connected between the output terminal and the earth and outputting a feedback voltage; and an oscillating circuit performing an ON/OFF control of the switching element at a frequency corresponding to the received feedback voltage. The DC/DC converter further includes: a detection circuit which detects an external magnetic field and outputs a signal that is different depending on whether or not the detected magnetic field exceeds a predetermined threshold; and a control circuit performing a control of the DC/DC converter according to the signal, to suppress an overcurrent of the DC/DC converter in a strong magnetic field.

When installing a display device for medical purpose to be used as a monitor in, for example, an environment where a magnetic field generation device, such as an MRI (Magnetic Resonance Imaging system), is used, electronic parts that drive the display device might possibly cause malfunction due to changes of the surrounding magnetic field and perform operations that are not assumed. In particular, since an inductor included in a power supply circuit for driving the display device is directly affected by the surrounding magnetic field, the inductor may perform operations different from expected operations. This may cause the power supply circuit to malfunction. In addition, it can be considered that an integrated circuit (IC) is also affected by a magnetic field, and the integrated circuit may also perform operations different from expected operations.
In particular, a switching circuit is used for a voltage step-up circuit or a voltage step-down circuit as a component of a power supply circuit (DC/DC converter). The switching circuit is mainly constituted by an inductor, a field-effect transistor (FET), a rectifying diode, and a smoothing capacitor, and generates an output voltage having a voltage value different from an input voltage by converting the input voltage. Further, the DC/DC converter is provided with an overcurrent prevention circuit for preventing danger in electronic parts, such as heat and fire, when the output current becomes unusually large.
When a display device including a DC/DC converter having such a configuration is placed into a space where there is a strong magnetic field (referred to as "in a strong magnetic field"), the inductor is affected by the magnetic field to approach toward magnetic flux saturation. This causes increase of the current value. If the current value exceeds a threshold of the overcurrent prevention circuit, the DC/DC converter enters into a latch operation. If the latch operation is activated, the DC/DC converter halts the output. As a result, the display device halts and displays nothing. That is, when the display device is placed in a strong magnetic field, there is caused a problem that the display device stops suddenly as a result of changes of the surrounding magnetic field and there is needed an operation work to restore the stopped display device.
In order to avoid such a problem, for example, Patent Literature 1 identified below discloses a power conversion device including: an AC/DC converter for converting an AC voltage of an AC power source into a DC voltage; a smoothing capacitor for smoothing the DC voltage; a switching circuit which is constituted by a power transistor and converts the smoothed DC voltage into an AC voltage by performing an ON/OFF control of the power transistor; a PWM circuit which compares a command voltage with a carrier wave and outputs a control signal for performing the ON/OFF control of the power transistor of the switching circuit; and a comparator which determines whether or not there is magnetic flux saturation of a reactor for suppressing higher harmonic noise connected between the AC power source and the power conversion device and changes a switching frequency of the carrier wave when it is determined that there is magnetic flux saturation. This publication describes the following. In order to prevent the magnetic saturation of the reactor for suppressing higher harmonic noise, an inverter device that drives a motor with variable speed compares the magnetic flux detected by the magnetic flux detector with a pre-designated threshold level. If the magnetic flux exceeds that level, the inverter device decreases the oscillation frequency for controlling the power transistor of the power supply circuit in order to avoid a resonance frequency of an LC constituted by a reactor and a smoothing capacitor provided next to the reactor. After decreasing the oscillation frequency, the magnetic flux is detected again. If the magnetic flux is larger than a previous detected magnetic flux, the inverter device increases the oscillation frequency to change the oscillation frequency within a frequency domain where the reactor does not undergo magnetic saturation.
Incidentally, Patent Literature 2 identified below discloses a power control device for generating an electric power for driving an amplifier circuit that amplifies signals for transmission. The power control device includes: a generation means for generating a PWM signal using a maximum voltage value per unit time of a transmitting signal that should be outputted from the amplifier circuit according to the signal for transmission; a selection means; and a power generation means which includes a plurality of inductors including inductors having different inductance, for generating the electric power on the basis of the PWM signal by a chopper circuit that uses an inductor selected from among the plurality of inductors by the selection means. The selection means acquires a value reflecting the maximum voltage value, compares the value with a pre-set one or more thresholds, and selects an inductor to be used in the power generation means according to the comparison result. This publication describes providing two series of voltage step-up circuit lines in advance in the voltage step-up circuit, and changing the voltage step-up path (mainly an inductor) according to, for example, an output voltage value and load.
Incidentally, Patent Literature 3 identified below discloses a device including a reactor and a switching element, for use in a voltage converter that converts an input voltage into a predetermined output voltage by controlling the amount of current that passes the reactor with periodic switching control of the switching element. The device includes: a current detection section for sensing the amount of the current of the reactor; and a detection control section for sensing a change in capacitance of the reactor on the basis of a plurality of sensed values each obtained in the current detection section at a plurality of moments including a moment different from a center moment of an ON period or an OFF period of the switching element and one the basis of a reference value with respect to the sensed value when the capacity of the reactor has a predetermined value. This publication describes sensing the current when the reactor current increases as a result of, for example, deterioration of the reactor, and switching the switch OFF or reducing the SW period when there is a difference between the sensed electric current and that of a normal state (reference value).
Incidentally, Patent Literature 4 identified below discloses an actuator driving device for driving an electromagnetic actuator. The actuator driving device includes: a voltage step-up circuit for increasing a power supply voltage; and an increased voltage control means in downstream of the voltage step-up circuit. This publication describes monitoring the input voltage, and when the input voltage decreases, making the output voltage small by switching a feedback partial voltage resistance value of the voltage step-up section, and switching on and off the switch according to the determined result of the input voltage sensor.
Incidentally, Patent Literature 5 identified below discloses a chopper circuit including: two main reactors which are two separated body and constitute one reactor equivalently; a main switch including one pole connected to one end of the serially-connected main reactors and the other pole directly connected to one voltage terminal of a DC power supply; a serially-connected body of a snubber diode and a snubber capacitor, connected between both poles of the main switch; and an auxiliary switch connected between a junction point of the snubber diode and the snubber capacitor, and a junction point of the serially-connected two main reactors. The auxiliary switch makes the voltage of the snubber capacitor zero voltage, thereby, to make the voltage at the time of turning on the main switch zero voltage. This publication describes, with respect to ON/OFF timing of each switch, a soft switching operation that switches S2 ON slightly earlier than S1, and a regenerative operation that switches S2 ON simultaneous with S1 or later than S1.


The present disclosure provides methods of preparing glucagon-like peptide-1 (GLP-1) receptor modulators, such as compounds of Formula (II) or (VI), or intermediates thereof. The compounds that may be prepared by the described methods are useful for regulating blood glucose levels and/or treating a disease mediated by a GLP-1 receptor (e.g., diabetes).

Supply of galanal A and galanal B compounds having antimicrobial, anti-cancer, anti-atherosclerosis, anti-diabetes and anti-platelet activities is conventionally provided by the flower bud, rhizome, stem, leaf and seed from several species of Zingiberaceae. The structures of galanal A and galanal B are shown below, with the number assignment of the carbon atoms.

However, the levels of galanal A and galanal B are very low in these edible plants. So far, there is no viable synthetic route for the preparation of galanal A and galanal B. Meanwhile, the effects of galanal A or galanal B in the treatment of diseases mediated by the GLP-1 (Glucagon-Like Peptide-1) receptor have not been investigated yet.

Synthesis of galanal compounds and analogues thereof


A radio data communication device that can perform a packet communication with the packet configuration suitable for transmission of a large volume of data in packet communications utilizing a low rate transmission mode and a high rate transmission mode. The transmitter side transmits packets only in a low rate mode or in a high rate mode after transmission in a low rate mode or only in a high rate mode. The receiver side simultaneously demodulates packets in the low rate mode and the high rate mode to detect the synchronous signal for each mode and judges whether or not in which mode the data has been transmitted, thus selecting the successive receive mode.

The present invention relates to a radio packet data communication device suitable in use for radio local area networks (LANs) and to a radio data communication method.
In most conventional communication systems, the modulation mode and the transmission rate are not changed from beginning to end during packet data communications via radio. However, in some communication systems, the modulation mode and the transmission rate are changed, if necessary, during communications. Such systems have a slow rate transmission mode (hereinafter referred to as a low rate mode) and a fast rate transmission mode (hereinafter referred to as a high rate mode). Communications are done using both packets each which is first transmitted in a low rate mode and then transmitted or received in a high rate mode and packets each which is transmitted or received in a low rate mode from beginning to end.
As an example of conventional data communications including a low rate mode and a high rate mode, there is radio data communication in which various flag signals and control signals are certainly transmitted in the low rate mode, and then communications are established using packets for transmitting information data in the high rate mode and packets for transmitting only an ACK (ACKnowledgement) signal in the low rate mode. FIG. 4 is a diagram showing the configuration of a packet for a mode selection in the conventional radio data communications. In the packet, the leading portion in a low rate mode is a preamble portion (training period) while the leading portion in a high rate mode is a preamble portion (training period). In the preamble portion, information data portion is demodulated after the carrier detection and synchronous detection.
The conventional radio data communication system always begins to communicate in the low rate mode. If the rate mode type is not notified in advance to the receiving side, the system cannot ensure communications only in the high rate mode. When communication for a large volume of information data such as VOD (video-on-demand) is desired after establishment of communication protocols, the operation of changing the low rate mode to the high rate mode must be repeated for each packet. This results in the system operation with poor efficiency.
As an another example, JA-P-150440/1992 discloses a radio data transmission system in which the transmission rate is selected. In this radio data transmission system used for the MCA (Multi-Channel Access) business activity radio or the like, a link establishment signal is simultaneously subjected to a MSK (Minimum Shift Keying) demodulation and an AM-MSK (AM-Minimum Shift Keying) demodulation. Thereafter, the data transmission mode upon transmission with the data format for MSK modulation or AM-MSK modulation is selected based on the detection condition of the frame synchronous signal of the link establishment signal in each of the MSK demodulation and the AM-MSK demodulation. Thus the current transmission rate is selected by transmitting the link acknowledgment signal with the selected format.
In the AM-MSK modulation corresponding to a high rate mode, demodulation is performed 2 bits by 2 bits. That is, one bit is used for the AM-demodulation while one bit is used for the MSK demodulation. Hence, since the bit rate is twice that of the MSK modulation corresponding to the low rate mode, the transmission efficiency is poor. Moreover, when the modulation mode is changed, the link must be established every time. Hence, this means that the data communication device in which a low rate mode and a high rate mode are selected in packet units has a poor transmission efficiency.

Radio data communication device and radio data communication method


A sliding bearing 1 includes: a synthetic resin-made upper casing 2 which is fixed to a vehicle body side via a mounting member; a synthetic resin-made lower casing 3 which is superposed on the upper casing 2 and on which a spring bearing surface for a suspension coil spring is formed; a synthetic resin-made sliding bearing piece 5 disposed in an annular space 4 between the upper casing 2 and the lower casing 3; and an annular inner seal member 8 and an annular outer seal member 9, both made of a synthetic resin, for respectively sealing an annular gap 6 on an inner peripheral side in a radial direction X and an annular gap 7 on an outer peripheral side in the radial direction X between the upper casing 2 and the lower casing 3, the annular gap 6 and the annular gap 7 allowing the annular space 4 to communicate with the outside.

In general, a strut-type suspension is mainly used for a front wheel of a four-wheeled motor vehicle, and is so arranged that a strut assembly incorporating a hydraulic shock absorber in an outer cylinder integrated with a main shaft is combined with a suspension coil spring. Among such suspensions, there is a type in which when the strut assembly rotates together with the coil spring in the steering operation, the piston rod of the strut assembly rotates, and a type in which the piston rod does not rotate. In either type, there are cases where, instead of a rolling ball bearing, a synthetic resin-made sliding bearing is used between a mounting member on the vehicle body and an upper spring seat of the coil spring, so as to allow smooth rotation of the strut assembly.


A system for non-invasively monitoring a stress level of a subject is presented. A sensor is configured to monitor an attribute of the subject. A housing is configured to removably attach to the subject, the housing includes a processor in communication with the sensor, the processor is configured to retrieve data from the sensor, and use the data retrieved from the sensor to determine a stress level of the subject.

Chronic stress is detrimental to one's health and can lead to many stress-based or stress-induced diseases. The difficulty in managing stress, from both a clinical and societal perspective, is that stress is difficult to quantify—what is stressful for one person may not be for another. Some stress is essential in life and, in healthy amounts, stress can provide motivation to accomplish goals. Sometimes stress is necessary in order for the body to protect itself and to overcome obstacles. But the long-term effects of prolonged physiological and psychological stress can and will cause the body harm.
A number of different techniques exist for determining the stress level of a subject. Example techniques include, for example, heart rate variability (HRV) analysis, biological impedance analysis (BIA), body surface temperature analysis, body core temperature analysis, muscle twitch analysis, and respiratory rate analysis.
Heart rate variability (HRV), for example, is a measure of the fluctuations of the heartbeat. Even the beats of a resting heart rate are not perfectly routine or rhythmic, with some variability in the heartbeat frequency. Study of this heartbeat variability is a non-invasive technique providing information about both parasympathetic and sympathetic activity within a subject. Although there are limitations, simple time and frequency domain techniques are commonly used to give quantitative measures allowing implications about stress to be understood.
BIA relies upon skin impedance to analyze a subject's stress. Body surface and body core temperature analysis rely upon body temperatures to analyze a subject's stress. Muscle twitch analysis involves detecting muscle twitch within a subject to analyze stress and respiratory rate analysis looks at a subject's respiratory rate to determine stress.
Although these techniques provide some methods for analyzing a subject's stress, no devices exist that automatically use these techniques to determine a user's stress.

Arizona Board of Regents, a body of corporate of the State of Arizona


A device for application of material to a surface, for example, biocompatible material to a tissue surface in a medical or clinical setting, is adapted to receive one or more biocompatible materials and one or more sources of pressurized medical gas, and to deliver these biocompatible materials via the medical gas(es) to a tissue surface or other surface. A regulation system controls flow of medical gas at a variety of pressures, and flow of biocompatible agent or agents, allowing agents to be sprayed or otherwise deployed onto a tissue surface. Switching apparatus operably connected to the regulation system directs a set of preset treatment positions allowing sequential application of biocompatible materials under various conditions in conjunction with an overall treatment protocol. The device can be used to apply a photoinitiating primer and polymeric sealant to a tissue surface, followed by light activation to form a polymer coating on the surface. The device can easily be operated in a variety of orientations by a user, with switching apparatus arranged for logical, stepwise progression through the protocol in any orientation.

Medical devices are available for application of biocompatible agents to tissue surfaces. Devices range in type from those designed simply to extrude material from a reservoir directly onto a surface, to those able to spray material onto a surface and then to activate the material to change it in some way, for example by exposing it to polymerizing light. Devices exist that are designed to apply two or more agents to a tissue surface that react with each other spontaneously, or upon the application of light, to change harden.
Examples of devices for delivery of one or more agents to a tissue surface can be found in U.S. Pat. No. 5,582,596 (Fukunaga, et al.), U.S. Pat. No. 5,665,067 (Linder, et al.), U.S. Pat. No. 5,749,968 (Melenson, et al.), and in International Patent Application Serial No. PCT/US99/21521 (International Patent Publication WO 00/15117; Pichon, et al.). The latter (WO 00/15117) describes a gas-powered spraying device that can be used for single or multi-part reactive medical polymer compositions. In use, one or more fluids are sprayed independently at a tissue surface by introducing the fluids into a medical gas. The fluids can be stored in reservoirs which are attachable to the device at inlet ports fluidly connectable to an outlet of the device at which the fluids can be independently introduced into flowing gas and thereby delivered to the tissue surface. Gas flow is provided at two flow levels, including a high level flow for active spraying of material onto the tissue surface, and a low level flow to remove drips from the outlet and prevent clogging, to improve device reliability. In one arrangement, the two fluids are separately applied to a single tissue surface area at which they react to harden, spontaneously or photochemically.
In the above and other systems, it is often important to apply two or more fluids independently, and in some cases sequentially, to a tissue surface. In many cases it is desirable to apply fluids evenly or unevenly, depending upon various conditions, and in variable ratios between fluids. Although the above and other systems are useful in many instances, there remains a need in the art for improved devices that are even more convenient and versatile for simple and rapid application of material to tissue surfaces under a variety of conditions, including a variety of tissue surface conditions.

Multi-pressure biocompatible agent delivery device and method


For use with an automated mechanical transmission system including an electrically actuated shift mechanism having a motor, a method of controlling the shift mechanism is provided for shifting the transmission out of gear during a reduced torque shift window by quickly detecting motor motion. The shift mechanism is first energized with a low effective voltage signal to minimize power consumption and avoid overheating the motor, and then with a high effective voltage signal upon detection of motor motion, to quickly shift the transmission out of gear.

Transmission systems, such as those for heavy-duty trucks, which automatically shift the transmission based on throttle position, vehicle speeds, engine speeds and the like, are well known in the art. In these systems, transmission shifting can be effected in various ways. For example, the transmission system may utilize pressurized fluid to frictionally engage members to achieve a desired gear ratio. Alternatively, the system may incorporate electronic logic in conjunction with electric actuators which operate to engage and disengage mechanical clutches to achieve a desired gear ratio. These electric actuators could take the form of electric motors.
For example, United States patents relating to the automatic shifting of transmissions include U.S. Pat. No. 4,911,031, issued to Yoshimura et al., and U.S. Pat. Nos. 5,053,961 and 5,053,962, both issued to Genise and assigned to the assignee of the present invention.
In applications where a permanent magnet electric motor is utilized as a positioning device, it would be desirable to control the motor to quickly shift the transmission out of gear to the neutral position. However, the desire for this quick motion must be balanced against excessive power consumption, as well as the possibility of overheating the motor when the motor is stalled due to, for example, torque lock. Existing systems apply the same level of current to the motor during the entire preload and move to neutral motion. The speed at which the transmission can be shifted out of gear is limited by the level of current which the system can tolerate during preload.

Method of controlling an automated mechanical transmission shift mechanism


Systems and methods are directed to a memory element comprising a hybrid giant spin Hall effect (GSHE)-spin transfer torque (STT) magnetoresistive random access memory (MRAM) element, which includes a GSHE strip formed between a first terminal (A) and a second terminal (B), and a magnetic tunnel junction (MTJ), with a free layer of the MTJ interfacing the GSHE strip, and a fixed layer of the MTJ coupled to a third terminal (C). The orientation of the easy axis of the free layer is perpendicular to the magnetization created by electrons traversing the GSHE strip between the first terminal and the second terminal, such that the free layer of the MTJ is configured to switch based on a first charge current injected from/to the first terminal to/from the second terminal and a second charge current injected/extracted through the third terminal into/out of the MTJ via the third terminal (C).

Magnetoresistive Random Access Memory (MRAM) is a non-volatile memory technology that has response (read/write) times comparable to volatile memory. In contrast to conventional RAM technologies which store data as electric charges or current flows, MRAM uses magnetic elements. As illustrated in FIGS. 1A and 1B, a magnetic tunnel junction (MTJ) storage element 100 can be formed from two magnetic layers 110 and 130, each of which can hold a magnetic moment, separated by an insulating (tunnel barrier) layer 120. One of the two layers (e.g., fixed layer 110), is set to a particular polarity. The other layer's (e.g., free layer 130) polarity 132 is free to change to match that of an external magnetic field that can be applied. A change in the polarity 132 of the free layer 130 will change the resistance of the MTJ storage element 100. For example, when the magnetization polarities are aligned, FIG. 1A, a low resistance state exists (parallel "P" magnetization low resistance state "0"). When the magnetization polarities are not aligned, FIG. 1B, then a high resistance state exists (anti-parallel "AP" magnetization high resistance state "1"). The illustration of MTJ 100 has been simplified and those skilled in the art will appreciate that each layer illustrated may comprise one or more layers of materials, as is known in the art. For example, one or more additional layers made of anti-ferromagnetic materials may be added on top of free layer 130 in order to improve the speed and efficiency of switching of the free layer.
Referring to FIG. 2, a memory cell 200 of a conventional MRAM is illustrated for a read operation. The cell 200 includes a transistor 210, bit line 220, digit or source line 230 and word line 240. The cell 200 can be read by measuring the electrical resistance of the MTJ 100. For example, a particular MTJ 100 can be selected by activating an associated transistor 210 (transistor on), which can switch current from a bit line 220 through the MTJ 100. Due to the tunnel magnetoresistive effect, the electrical resistance of the MTJ 100 changes based on the orientation of the magnetization polarities in the two magnetic layers (e.g., 110, 130), as discussed above. The resistance inside any particular MTJ 100 can be determined from the current, resulting from the magnetization polarity of the free layer. Conventionally, if the fixed layer 110 and free layer 130 have the same magnetization polarity, the resistance is low and a "0" is read. If the fixed layer 110 and free layer 130 have opposite magnetization polarity, the resistance is higher and a "1" is read.
Unlike conventional MRAM, Spin Transfer Torque Magnetoresistive Random Access Memory (STT-MRAM) is known in the art, where an STT-MRAM bit cell uses electrons that become spin-polarized as the electrons pass through a thin film (spin filter). STT-MRAM is also known as Spin Transfer Torque RAM (STT-RAM), Spin Torque Transfer Magnetization Switching RAM (Spin-RAM), and Spin Momentum Transfer (SMT-RAM). During the write operation, the spin-polarized electrons exert a torque on the free layer, which can switch the magnetization polarity of the free layer. The read operation is similar to conventional MRAM in that a current is used to detect the resistance/logic state of the MTJ storage element, as discussed in the foregoing. As illustrated in FIG. 3A, a STT-MRAM bit cell 300 includes MTJ 305, transistor 310, bit line 320 and word line 330. Transistor 310 is turned on for both read operations and write operations, in order to allow current to flow through MTJ 305, so that the logic state can be read or written.
Referring to FIG. 3B, a more detailed diagram of a STT-MRAM cell 301 is illustrated, for further discussion of the read/write operations. In addition to the previously discussed elements such as MTJ 305, transistor 310, bit line 320 and word line 330, source line 340, sense amplifier 350, read/write circuitry 360 and bit line reference 370 are illustrated. As discussed above, during a read operation, a read current is generated, which flows between the bit line 320 and source line 340 through MTJ 305. When the current is permitted to flow via transistor 310, the resistance (logic state) of the MTJ 305 can be sensed based on the voltage differential between the bit line 320 and source line 340, which is compared to a reference 370 and then amplified by sense amplifier 350. Those skilled in the art will appreciate the operation and construction of the memory cell 301 is known in the art.
With reference now to FIG. 4, a memory array comprising STT-MRAM cells, such as, cell 300 of FIG. 3A, is illustrated. As shown herein, each bit cell has 3 terminals, viz., a word-line select terminal (WL[*]), a bit-line terminal (BL[*]), and a source-line terminal (SL[*]). This cell structure with a single access transistor such as transistor 310 of FIG. 3B is referred to as a 1T1J (one-transistor-one-MTJ) implementation, which is known to consume approximately one-half to one-fourth of the area consumed by conventional SRAM cells. As shown, the transistors are used to switch on or off the connection between the MTJ and SL[i], where the transistors are controlled by the word-line select terminals respectively.
In more detail, during write operations, the MTJs of the STT-MRAM bit cells are configured as programmable resistors of value of ˜2.5-5K ohms. For writing a particular bit cell, the corresponding selected word line is asserted and all unselected word lines are de-asserted. Appropriate voltages for the value to be written are set on BL[0, 1, 2 . . . ] and SL[0, 1, 2 . . . ]. An overdrive voltage may be applied on the transistor gate to avoid the gate-drain voltage of the transistor (Vgd) to drop to zero, as write operations are bi-polar (i.e., current flows in one direction for writing logic 0, and flows in the opposite direction for writing logic 1). Further, the write operations on STT-MRAM bit cells typically require a relatively large current (˜150 uA) due to the STT spin polarized current described previously.
In the case of read operations on a bit cell [i] for example, the corresponding selected word line is asserted and all unselected word lines are de-asserted. Both corresponding BL[i] and SL[i] are connected to a sensing circuit [i] (e.g., sense amplifier 350 of FIG. 3B), and the current flow is compared with the reference (e.g., reference 370 of FIG. 3B). If the current is greater than the reference, then logic 0 is sensed, otherwise logic 1 is sensed. For read operations, there is no need for gate overdrive voltage, as read operations are uni-polar.
While STT-MRAM technology offers significant improvements over conventional SRAM technology for non-volatile memory cells, for example, in terms of size, speed, cost, area, etc., advances in the area of magnetic cells have been made, which allow for further improvements in these regards. For example, one such advancement is observed in the case of magnetic cells which utilize a so-called spin Hall effect (SHE).
With reference to FIG. 5A, SHE is demonstrated in conductor 500. Electrons 509 passing through conductor 500 in the direction indicated, get polarized on the surfaces 502, 504, 506, and 508 along the directions indicated by arrows 501, 503, 505, and 507 respectively due to spin-orbit coupling. A spin Hall ratio is defined as
      θ    SH    =                    Js                          /                                  (                      ℏ                                                                          h                                      /                                    2                    )                            Jc                          /                        e              .
While SHE can be used to induce magnetic polarity along the directions 501, 503, 505, and 507, the effect can be improved by using special material (such as beta-tungsten) with appropriate thickness (such as thickness of just a few nanometers) for conductor 500, for example, as described in Pai et al. published as "Spin transfer torque devices utilizing the giant spin Hall effect of tungsten," Applied Physics Letters, §101, 122404, 2012 (hereinafter, the Pai reference). In more detail FIG. 5B illustrates conductor 500 with length (L), thickness (t) and width (W), wherein, with reference to Pai, an improvement θSH is shown in orders of magnitude, up to ˜0.33 times. This leads to a so-called giant spin Hall effect (GHSE).
The spin current generation efficiency is provided by the following equation:
                    I        S                    I        C              =                            Js          A                          Jc          a                    =                                    θ            SH                                          A            a                          =                              θ            SH                                          L            t                                ,where "IS" is the spin current a "IC" is the charge current. The spin current generation efficiency IS/IC can be further boosted by making appropriate changes to dimensions of conductor 500. For example, for a value of θSH=0.30, L=50-100 nm, and t=2 nm, it is seen that the ratio IS/IC can be as high as 7.5-15. This spin current generation efficiency in the order of ˜7.5-15, can be typical, considering that the ratio of L/t is ˜25-50, is typical for cases where the thickness "t" is only a few nanometers whereas the length "L" is in the order of tens of nanometers. In comparison, the spin current generation efficiency from STT polarization is merely ˜0.6.
Further, the θSH has improved over three orders of magnitude (˜1000×) to ˜0.3 based on the past few years' advances in SHE material research as shown in FIG. 5C (derived from Spintronics Research at Cornell University by Liu et al.), particularly for conductor materials such as beta-tungsten, beta-tantalum, and platinum, etc. These improvements relate to reasons why GSHE is considered to be "giant" in comparison to previously demonstrated SHE. The GSHE provides an efficient method to convert electric current based on electrons 509 into spin current, which can be used for providing switching current to MTJ cells.
Moreover, in comparison to STT-MRAMs, with the same resistance of the MTJ, the programming power using the GHSE effect can be approximately 50-200 times lower, which means that it is easier to write MTJs based on GHSE, which in turn, translates into smaller memory cells and high memory density. Moreover, a cap for the write current (Iwrite) observed for STT-MRAM (in order to avoid breakdown of the tunnel or barrier layer) is eliminated using GHSE. As shown, a magnetic element 510 placed on top of conductor 500 can get polarized in the direction indicated by arrow 501. As previously described, the ratio IS/IC can be varied by adjusting area A (=L*w) or area a (=t*w), or in other words, by adjusting the ratio, L/t. If magnetic material 510 is placed in the orientation shown, where width W is wider than thickness t, the direction 501 influences the polarization of magnetic material 510. More specifically, when magnetic material 510, configured as a free layer, is placed on top of conductor 500, configured as a spin-orbital coupling layer, the spin orientation 501 from spin Hall effect can influence the magnetization of the free layer magnetic material 510.
With reference now to FIG. 6A, a side view of a conventional memory element 600 that is switched (programmed, or written) by SHE (or more specifically GSHE) is illustrated. A SHE/GSHE strip comprising conductor 500 (referred to simply as a GSHE strip 500 in this case), which may be formed from strong spin-orbit coupling material, such as β-W, β-Ta, or Pt is formed between terminals A and B. Terminals A and B may be formed from metals such as copper. An MTJ 601 is placed above the GSHE strip 500, with a free layer of MTJ 601 adjacent to and in contact with GSHE 500. Write current Iw is passed through the GSHE strip in the direction indicated between A and B. Based on the induced spin polarization, the free layer of MTJ 601 can be switched. This provides a much more efficient way of programming MTJ 601 than in the STT-MRAM cell structure 301 illustrated in FIG. 3B. Additionally, in memory element 600, optional layers Ru, and CoFe, and an anti-ferromagnetic layer (AFM), and/or a synthetic antiferromagnetic layer (SAF) along with a top electrode are also depicted as formed on MTJ 601. MTJ 601 is read based on sensing the read current Iread, as will be further explained in following sections.
With reference to FIG. 6B, a top view of MTJ 601 switched by a conventional SHE/GSHE arrangement of FIG. 6A is shown. The direction 602 is perpendicular to the write current from/to terminal A to/from terminal B, and is referred to as the easy axis of MTJ 601. The free layer of MTJ 601 resides at a minimal magneto-static energy region along easy axis 602. In more detail, easy axis orientation is a property of the free layer based on the shape of the free layer. The free layer will always be magnetized along the easy axis when external magnetization force is removed. In conventional SHE switched MTJ, the SHE write current is orthogonal to the easy axis orientation such that the SHE induced spin orientation is in line with easy axis orientation. Thus, easy axis 602 is considered to be oriented along the x direction in FIG. 6B, and is transverse to the direction of write current Iw. On the other hand, hard axis 604 of MTJ 601, which is perpendicular to easy axis 602, is formed along the y direction. The free layer of MTJ 601 interfaces GSHE strip 500 and easy axis 602 is in line with or parallel to the corresponding GSHE induced spin orientation. In other words, the orientation of easy axis 602 of the free layer of MTJ 601 is parallel to the magnetization axis created by electrons traversing GSHE strip 500 between the two terminals A and B. As explained previously, the MTJ is in a low resistance state (P state) if the magnetization of the free layer is aligned (parallel) to the magnetization of the fixed layer; and the MTJ is in a high resistance state (AP state) if the magnetization of the free layer is anti-aligned (anti-parallel) to magnetization of the fixed layer.
With reference to FIG. 6C, an equivalent circuit of conventional SHE/GSHE switched MTJ element 600 is depicted, along with the symbol for the device. Under operational conditions, when the current between terminals A and B is no less than a threshold (˜20 uA), the MTJ switches to state '0' (low MTJ resistance) if current flows from A to B; and to state '1' (high MTJ resistance) if the current flows in the opposite direction, from B to A. When the current between A and B is less than the threshold (˜20 uA), the MTJ retains its previous state (either '0' or '1').
While the above-described conventional SHE/GSHE switched MTJ element 600 exhibits vast improvements over known STT-switched MTJs in STT-MRAM structures, known approaches to utilizing the conventional SHE/GSHE switched MTJ elements suffer various limitations, which will be discussed in detail below. According to the implementations and parameters, the conventional SHE/GSHE switched MTJ elements may be characterized as SHE-switched or GSHE-switched MTJs. In the discussion of these conventional structures, the conventional SHE/GSHE switched MTJ elements (e.g., element 600) have been assumed to be memory elements for SHE-MRAMs, for the sake of generality.
Conventional Implementation 1—1T1J SHE-MRAM
In FIG. 7, a first conventional implementation related to a memory array comprising SHE-MRAM memory cells comprising 1T1J structures (i.e., one access transistor per every memory element comprising an MTJ) is depicted. Each bit cell has 4 terminals: a Word-line Select Terminal, a Write Terminal, a Write Negated Terminal, and a Read Terminal. The conventional implementation for each bit cell [i] involves connecting the Word-line Select Terminal to WL[i], the Write Terminal to WBL[i], the Write Negated Terminal to WBLn[i], and the Read Terminal to RBL[i]. In each memory cell, the connection between the Write Terminal and WBL[i] is switched on/off via the corresponding access transistor controlled by the Word-line Select Terminal.
During a write operation on a particular bit cell (701) the corresponding selected word line is asserted, and all remaining unselected word lines are de-asserted. Appropriate voltages are accordingly set for WBL[0, 1, 2 . . . ] and WBLn[0, 1, 2 . . . ], and RBL[0, 1, 2 . . . ] are floated. For the sake of explanation in the entirety of this discussion (unless indicated otherwise), zero resistance is assumed for the current paths where the access transistors are switched on, and an infinite resistance is assumed for the current paths where the access transistors are switched off. Further, for different kinds of paths which may arise in this disclosure, numerical references have been added, which will be explained below in each pertinent section. Accordingly, in FIG. 7, an intended functional current path has write resistance Rwr for the write to bit cell 701, where the intended functional current path is shown with the reference numeral "(1)". During a write operation on bit cell 701, unintended current paths result for cells 701 and 702, which are indicated with the reference numeral "(2)," each with resistance twice the read resistance Rrd along with Rwr (i.e., 2Rrd+Rwr). In this case, it is noted that even though these unintended paths do not cause write functionality to fail for the write operation, since Rrd is much bigger than Rwr (>10x), they nevertheless collectively consume significant additional power.
In the case of a read operation (on bit cell 704), corresponding selected word line is asserted, and all remaining unselected word lines are de-asserted. Appropriate voltages are set on WBL[0, 1, 2 . . . ], and on RBL[0, 1, 2 . . . ] to have current flow from/to WBL[i] to/from RBL[i]; and WBLn[0, 1, 2 . . . ] are floated. The intended functional current path for the read operation is shown with reference numeral "(4)," for cell 704 with resistance Rrd. The unintended paths during the read operation are shown with reference numeral "(3)," for cells 703/704, each with resistance Rrd+Rwr. However, it is noted that in this case, these unintended paths "(3)" during read operations do break read functionality, as the resistance change on the unintended paths can disguise, or be confused with, the resistance of the intended path.
Conventional Implementation 2—1T1J SHE-MRAM
In FIG. 8, a second conventional implementation related to a memory array comprising SHE-MRAM memory cells comprising 1T1J structures, is depicted. Once again, each bit cell has 4 terminals: a Word-line Select Terminal, a Write Terminal, a Write Negated Terminal, and a Read Terminal. The conventional implementation for each bit cell [i] involves connecting the Word-line Select Terminal to WL[i], the Write Terminal to WBL[i], the Write Negated Terminal to WBLn[i], and the Read Terminal to RBL[i]. In this implementation, the connection between the Read Terminal and RBL[i] is switched on/off via a transistor controlled by the Word-line Select Terminal.
During a write operation on a particular bit cell (801) the corresponding selected word line is asserted, and all remaining unselected word lines are de-asserted. Appropriate voltages are accordingly set for WBL[0, 1, 2 . . . ] and WBLn[0, 1, 2 . . . ], and RBL[0, 1, 2 . . . ] are floated. Following like reference numerals as FIG. 7, the intended functional current path is indicated as "(1)," for bit cell 801 with resistance Rwr. The unintended paths are shown as "(2)," each with resistance Rwr, for bit cells 801, 802, and 803. However, in this case, it must be noted that the unintended paths do break write functionality, as they induce unintended writes on bit cells 802 and 803.
In the case of a read operation (on bit cell 804), corresponding selected word line is asserted, and all remaining unselected word lines are de-asserted. Appropriate voltages are set on WBL[0, 1, 2 . . . ] and RBL[0, 1, 2 . . . ] (while WBLn[0, 1, 2 . . . ], are floated), in order to have current flow from/to WBL[i]/WBLn[i] to/from RBL[i]. For read operations in this implementation, intended functional path is shown as "(4)," with resistance Rrd. There are no unintended paths, and therefore no breaks in read functionality.
Conventional Implementation 3—1T1J SHE-MRAM
In FIG. 9, a third conventional implementation related to a memory array comprising SHE-MRAM memory cells comprising 1T1J structures, is depicted. Once again, each bit cell has 4 terminals: a Word-line Select Terminal, a Write Terminal, a Write Negated Terminal, and a Read Terminal. The conventional implementation for each bit cell [i] involves connecting the Word-line Select Terminal to WL[i], the Write Terminal to WBL[i], the Write Negated Terminal to WBLn[i], and the Read Terminal to RBL[i]. In this case, the connection between the Write Negated Terminal and WBLn[i] is switched on/off via a transistor controlled by the Word-line Select Terminal.
During a write operation on a particular bit cell (901) the corresponding selected word line is asserted, and all remaining unselected word lines are de-asserted. Appropriate voltages are accordingly set for WBL[0, 1, 2 . . . ] and WBLn[0, 1, 2 . . . ], and RBL[0, 1, 2 . . . ] are floated. Following similar naming conventions as above, the intended functional current path is shown as "(1)," for bit cell 901 with resistance Rwr The unintended paths are shown as "(2)," for cells 901 and 902, each with resistance 2Rrd+Rwr. The unintended paths during the write operation do not break write functionality, as Rrd is much bigger than Rwr (>10x), although these unintended paths collectively consume significant additional power.
In the case of a read operation (on bit cell 904), corresponding selected word line is asserted, and all remaining unselected word lines are de-asserted. Appropriate voltages are set on WBLn[0, 1, 2 . . . ], and on RBL[0, 1, 2 . . . ] to have current flow from/to WBLn[i] to/from RBL[i]. For read operations in this implementation, intended functional path are shown as "(4)," with resistance Rrd. The unintended paths are shown as "(3)," for bit cells 903 and 904, each with resistance Rrd+Rwr. These unintended paths do break read functionality, as the resistance change on unintended paths can disguise that of the intended path.
From the above three conventional implementations, it is seen that the 1T1J structures are fraught with drawbacks which render such implementations unsatisfactory for easy and correct read/write operations on the SHE-MRAM structures. Accordingly, conventional implementations pertaining to 2T1J structures with two access transistors per MTJ for each bit cell are also considered below.
Conventional Implementation 4—2T1J SHE-MRAM
In FIG. 10, a fourth conventional implementation related to a memory array comprising SHE-MRAM memory cells comprising 2T1J structures, is depicted. Once again, each bit cell has 4 terminals: a Word-line Select Terminal, a Write Terminal, a Write Negated Terminal, and a Read Terminal. The conventional implementation for each bit cell [i] involves connecting the Word-line Select Terminal to WL[i], the Write Terminal to WBL[i], the Write Negated Terminal to WBLn[i], and the Read Terminal to RBL[i]. In this case, the connection between the Write Terminal and WBL[i] is switched on/off via a first transistor controlled by the Word-line Select Terminal, and the connection between the Write Negated Terminal and WBLn[i] is switched on/off via a second transistor controlled by the Word-line Select Terminal.
During a write operation on a particular bit cell (1001) the corresponding selected word line is asserted, and all remaining unselected word lines are de-asserted. Appropriate voltages are accordingly set for WBL[0, 1, 2 . . . ] and WBLn[0, 1, 2 . . . ], and RBL[0, 1, 2 . . . ] are floated. The intended functional current path is shown as "(1)," with resistance Rwr. There are no unintended paths, and therefore, there are no paths which break write functionality.
Another consideration which arises in this case is related to the transistor gate overdrive requirement due to bi-polar writing. As current flows from/to the Write Terminal to/from the Write Negated Terminal for writing logic 1/0 respectively, with WL[i] set to Vdd, and WBL[i] to Vdd/Vss, and WBLn[i] to Vss/Vdd, one of the two transistors display elevated Vgs, and Vgd=0, thus the drive strength of that transistor is significantly reduced. Accordingly, a typical solution to this reduced drive strength is to overdrive gate line WL[i], which results in a complicated design; or in increased transistor size, which reduces memory density.
In the case of a read operation (on bit cell 1002), corresponding selected word line is asserted, and all remaining unselected word lines are de-asserted. Appropriate voltages are set on WBLn[0, 1, 2 . . . ], and on RBL[0, 1, 2 . . . ] to have current flow from/to WBLn[i] to/from RBL[i]. WBLn[0, 1, 2 . . . ] are set to have the same voltages as corresponding WBL[0, 1, 2 . . . ]. For read operations in this implementation, the intended functional path is shown as "(4)," with resistance Rrd. There are no unintended paths, and therefore, no related break in read functionality. Further, there does not arise a need for a transistor gate overdrive, as read operations are uni-polar.
Conventional Implementation 5—2T1J SHE-MRAM
In FIG. 11, a fifth conventional implementation related to a memory array comprising SHE-MRAM memory cells comprising 2T1J structures, is depicted. Once again, each bit cell has 4 terminals: a Word-line Select Terminal, a Write Terminal, a Write Negated Terminal, and a Read Terminal. The conventional implementation for each bit cell [i] involves connecting the Word-line Select Terminal to WL[i], the Write Terminal to WBL[i], the Write Negated Terminal to WBLn[i], and the Read Terminal to RBL[i]. In this case, the connection between the Write Terminal and WBL[i] is switched on/off via a first transistor controlled by the Word-line Select Terminal, and the connection between the Read Terminal and RBL[i] is switched on/off via a second transistor controlled by the Word-line Select Terminal.
During a write operation on a particular bit cell (1101) the corresponding selected word line is asserted, and all remaining unselected word lines are de-asserted. Appropriate voltages are accordingly set for WBL[0, 1, 2 . . . ] and WBLn[0, 1, 2 . . . ], and RBL[0, 1, 2 . . . ] are floated. The intended functional current path is shown as "(1)," with resistance Rwr. There are no unintended paths, and therefore, there are no paths which break write functionality.
Once again, the consideration related to the transistor gate overdrive requirement due to bi-polar writing arises. As current flow from the Write Terminal to the Write Negated Terminal for writing logic 1 with WL[i] setting to Vdd, WBL[i] to Vdd, and WBLn[i] to Vss, the transistors connecting the Write Terminal to WBL[i] display elevated Vgs, and Vgd=0, and therefore the drive strength of that transistor is significantly reduced. Accordingly, a typical solution to this reduced drive strength is to overdrive gate line WL[i] for that transistor, which results in a complicated design; or in increased transistor size, which reduces memory density.
In the case of a read operation (on bit cell 1102), corresponding selected word line is asserted, and all remaining unselected word lines are de-asserted. Appropriate voltages are set on WBLn[0, 1, 2 . . . ], and on RBL[0, 1, 2 . . . ] to have current flow from/to WBLn[i] to/from RBL[i]. WBLn[0, 1, 2 . . . ] are set to have the same voltages as corresponding WBL[0, 1, 2 . . . ]. For read operations in this implementation, the intended functional path is shown as "(4)," with resistance Rrd. There are no unintended paths, and therefore, no related break in read functionality. Further, there does not arise a transistor gate overdrive requirement as read operations are uni-polar.
Conventional Implementation 6—2T1J SHE-MRAM
In FIG. 12, a sixth conventional implementation related to a memory array comprising SHE-MRAM memory cells comprising 2T1J structures, is depicted. Once again, each bit cell has 4 terminals: a Word-line Select Terminal, a Write Terminal, a Write Negated Terminal, and a Read Terminal. The conventional implementation for each bit cell [i] involves connecting the Word-line Select Terminal to WL[i], the Write Terminal to WBL[i], the Write Negated Terminal to WBLn[i], and the Read Terminal to RBL[i]. In this case, the connection between the Read Terminal and RBL[i] is switched on/off via a first transistor controlled by the Word-line Select Terminal, and the connection between the Write Negated Terminal and WBLn[i] is switched on/off via a second transistor controlled by the Word-line Select Terminal.
During a write operation on a particular bit cell (1201) the corresponding selected word line is asserted, and all remaining unselected word lines are de-asserted. Appropriate voltages are accordingly set for WBL[0, 1, 2 . . . ] and WBLn[0, 1, 2 . . . ], and RBL[0, 1, 2 . . . ] are floated. The intended functional current path is shown as "(1)," with resistance Rwr. There are no unintended paths, and therefore, there are no paths which break write functionality.
Once again, the consideration related to the transistor gate overdrive requirement due to bi-polar writing arises. As current flow to the Write Terminal from the Write Negated Terminal for writing logic 0 with WL[i] setting to Vdd, WBL[i] to Vss, and WBLn[i] to Vdd, the transistors connecting the Write Negated Terminal to WBLn[i] display elevated Vgs, and Vgd=0, and therefore the drive strength of that transistor is significantly reduced. Accordingly, a typical solution to this reduced drive strength is to overdrive gate line WL[i] for that transistor, which results in a complicated design; or in increased transistor size, which reduces memory density.
In the case of a read operation (on bit cell 1202), corresponding selected word line is asserted, and all remaining unselected word lines are de-asserted. Appropriate voltages are set on WBL[0, 1, 2 . . . ], and on RBL[0, 1, 2 . . . ] to have current flow from/to WBL[i] to/from RBL[i]. WBLn[0, 1, 2 . . . ] are set to have the same voltages as corresponding WBL[0, 1, 2 . . . ]. For read operations in this implementation, the intended functional path is shown as "(4)," with resistance Rrd. There are no unintended paths, and therefore, no related break in read functionality. Further, there does not arise a transistor gate overdrive requirement as read operations are uni-polar.
Accordingly, it is seen that the implementation of SHE-MRAM using conventional SHE/GSHE switched MTJs (for example, as taught in International Application No. WO 2014/025838 to Buhrman et al., entitled "Electrically gated three-terminal circuits and devices based on spin hall torque effects in magnetic nanostructures,") and as discussed above with regard to conventional implementations 1-6, suffer from numerous drawbacks. For conventional implementations 1-3 which may improve density with 1T1J structures, it is seen that there are many breaks in read/write functionalities. For 2T1J conventional implementations 4-6, adding an extra access transistor, at the cost of lower density can accomplish read/write functionality in many cases, but are not efficient due to requirements of the overdrive voltages, and other drawbacks discussed in detail above.
However, it is desirable to achieve high density memory structures which can fully exploit the advantages of SHE/GSHE, while avoiding drawbacks related to transistor gate overdrive voltages, increased transistor sizing, and need for 2T1J structures. In other words, it is desirable to achieve memory structures which include 3-terminal devices based on GSHE principles, and which can accomplish high density and superior performance, in comparison to the above conventional implementations and conventional 2-terminal STT-MTJ devices.