Systems and methods for generating low or ultra-low concentrations of oil-based challenging compounds for filtration media are provided. Embodiments of the generators utilize bypass air in addition to the source of challenge. A HEPA filter which utilizes spunbond scrim material and ePTFE membrane for use in an aseptic pharmaceutical filtration air handling system for installation and testing is provided. The installation and testing configuration includes the ePTFE filter with a low or ultra-low concentration of challenging aerosol in the upstream side of the filter along with a scanning device for determining the upstream concentration, all completed in situ within a pharmaceutical air handling system. At the downstream side of the ePTFE filter is positioned another scanner which may be a discrete particle counter. The system and configuration allows for exposure to ePTFE filtration media for certification by low or ultra-low concentrations of oil based challenging compounds.

In most aseptic pharmaceutical cleanrooms, the final step in removing airborne particles occurs in a high efficiency particulate air (HEPA) or ultra-low penetration air (ULPA) filter that is delivering air into a controlled space. Whether the cleanroom attains and maintains its designed cleanliness class depends largely on the performance of these filters. Hence, it is a common and good practice to test the performance of all filters installed in cleanrooms to ensure that they meet the designed specifications. Filters are typically tested at the time of manufacture for overall efficiency and leaks. However, in some cleanrooms within regulated industries, such as the pharmaceutical industry, these filters are also required to be certified periodically to ensure acceptable performance during their service life. Various organizations issue recommended practices for certification of HEPA and ULPA type filters for filter leak tests and guidelines for testing and classifying such filters.
In current HEPA air filtration micro-glass media, the standard utilized in the pharmaceutical industry in aseptic processing has serious problems due to the media being fragile resulting in damage from handling, pressure, overloading and the like. Such damage can result in leaks of the filtration media thereby compromising functionality. Leakage and damage of microglass filtration media within the pharmaceutical cleanroom environment is significant such that the U.S. Food and Drug Administration has issued guidelines ensuring filtration effectiveness of microglass HEPA filters by testing on a regular basis. Testing of such microglass HEPA filters in such aseptic environment is completed using high concentration oil based aerosols such as DOP (dioctylphthlate), PAO (poly-alpha olefin), DEHS (Di-Ethyl-Hexyl-Sebacat), and other similar compounds measured by traditional photometers capable of measuring such upstream and downstream concentrations. The aerosols used for such filter leak tests and challenging of these filters should meet specifications for critical physicochemical attributes such as viscosity. Leakage threshold rates of 0.01% or greater of upstream concentration from these compounds is typically the testing limit at which the pharmaceutical installation and processing area would either have to replace the filter or repair the same. The upstream concentration typically is measured at the start and end of testing to ensure that the upstream challenge remains consistent over the life of the test. The filter face is scanned to identify defects in the filter media.
Since the 1960's HEPA filters have been tested using high concentrations (e.g., approximately 20 μg/liter) of aerosols such as PAO, DOP, DEHS, and other similar compounds. Traditionally, HEPA filters are tested with photometers which require a high (>10 μg/liter) upstream challenge concentration. Considering a leak size of 0.01% of the upstream concentration, this means that on the downstream side of the filter one must be able to detect a very small amount of PAO. The photometer has a lower limit of being able to measure small concentrations, which is why the larger upstream concentrations are required. A particle counter is another piece of equipment that can be used to leak test filters. Particle counters, unlike photometers, are only able to work with very low concentrations of PAO and are much more sensitive at very or ultra low concentrations of aerosol.
High concentrations of oil have a much greater impact on ePTFE than on glass media HEPA filters. Studies have shown that testing glass media HEPA filters with a photometer at high concentrations (e.g., approximately 20 μg/l) and with a particle counter at low concentrations (e.g., approximately 0.1 μg/l) yield consistent results in regards to sizing leaks. Therefore, there is a desire to develop test apparatus and methods for testing filters (especially, but not limited to, ePTFE HEPA filters) at low concentrations.
In general, however, there has not been a very convenient way to steadily produce a very low concentration of PAO. In the past a Laskin nozzle generator was used and the output was dumped into filters, or other output reduction methods were used. None of these have been ideal, however. The output of typical Laskin nozzle-based aerosol generators is governed by the amount of air flow exiting the nozzle tip. A standard Laskin nozzle requires approximately 2.65 cfm @ 20 psi of compressed air to enter the nozzle, thus resulting in 2.65 cfm of the aerosol mixture that will exit the generator. Air flow through the nozzle equates to flow combined with oil droplets out of the generator. In certain applications, the aerosol output of a generator operating on one Laskin nozzle will result in output concentrations with orders of magnitude higher than desired.
One possible solution to generating lower concentrations is to use a fraction of the Laskin nozzle output under the surface of the oil. Another possibility is to reduce the nozzle pressure. It is common practice to reduce the air pressure to a standard Laskin nozzle or to modify the nozzle by plugging one or more of the holes in the nozzle to reduce the overall aerosol output of the generator. The problem with using a smaller nozzle and/or lower nozzle pressures is that very little air passes through the nozzle and out of the tank. Another problem is that some specialized filter housings may require higher air flow. For example, some filter housings with aerosol injection/dispersion features are typically used with >2 cfm of airflow to inject the aerosol across the filter face. If very low flow were used, the aerosol may be difficult to be injected across the filter face in one of these units. Additionally, the time required for newly generated aerosol to exit the holding tank increases as nozzle flow decreases. This creates a slow response time in generator output at first startup or when attempting to change the nozzle pressure/generation rate of the generator. This increased exit time of the aerosol can also lead to an increase in aerosol particle size with time. A newly generated aerosol that is composed of small particles has a higher probability to grow in size by means of coalescence, ripening, agglomeration, etc., the longer it remains in a high aerosol concentration environment.
The DOP/PAO method for aseptic pharmaceutical room filtration application discussed above is required by regulation at least every 6-12 months by challenging the filtration media with a defined aerosol. The required aerosol challenge is maintained at a high concentration of about 20 μg PAO/L of air. A measurement of 15 μg of PAO/liter corresponds to about 20 grams of PAO/800 cfm filter/hour. For normal or standard microglass filtration media, a one-time oil based challenge compound may not negatively impact filter life of the media but may affect other structures of the filter. However, by testing at such concentrations on a regular basis, standard filter life including regular challenge testing can limit to less than five years the life cycle for microglass HEPA filtration.
In such standard challenging methodology for pharmaceutical applications and installs, a predefined challenging compound such as PAO is provided upstream of the filtration media in place. The PAO is injected into the airstream upstream of the in-situ media by nozzle or other known device at high concentration levels to properly determine filtration effectiveness. Injection devices such as a Laskin Nozzle create a poly-dispersed aerosol composed of particles with light scattering mean droplet diameters in the submicron size range. A challenge concentration, as mentioned, is provided up to about 20 μg/L which is continually introduced upstream of the filter for about three to four hours for a typical certification. An upstream challenging port in the filter housing is utilized for photometric analysis. The filter face is scanned on the downstream side with the photometer probe and leak sizes are calculated as a percent of the upstream challenge. Scanning is conducted on the entire face of the filter to generate proper leakage analysis. Probe readings of about 0.01% as leak criteria would be indicative of a significant leak but requires, as seen, fairly high concentrations of upstream PAO which can have deleterious effects on the filtering media and HEPA performance.
Significant problems also arise in the use of PAO challenge compounds. Significant fouling of the filtration media may occur over a plurality of challenging cycles. Further, such excessive challenging can cause the filter media to become less efficient, exhibiting more of a pressure drop and correspondent higher energy costs. Additionally, the PAO challenge compound has been shown to potentially cause damage to the filtering gel seals and gaskets resulting in potential leakage points. PAO may further cause liquification of silicon based gels or may harden or otherwise reduce the effectiveness of urethane based gel seals.
As a result, improved aerosol generators are required which can effectively produce aerosols of lower concentrations of appropriate challenge compounds to a filtration media, but which can do so consistently for the required amounts of time, and without causing excessive oiling or buildup on the filtration media, and without creating excessive pressure drop across the media.
Filter housings containing PAO dispersion manifolds can be used to provide a uniform aerosol distribution upstream of a filter when performing filter tests. These dispersion manifolds are designed to typically operate properly with a minimum of 2.65 cfm of air. When reducing the pressure below 20 psi for a full Laskin nozzle, or plugging a fraction of the nozzle holes, the output of the generator can fall below the optimal flow to effectively operate the dispersion manifolds. To compensate for the reduction of airflow through the generator outlet, one option is to increase the total output of the generator by adding additional supply air at the generator output. Under this operation, the newly formed aerosol exits the generator before combining with the additional supply air and the transit time for the aerosol to exit out of the holding tank is largely unaffected. However, if supply air is added at the generator output, there can be problems with the supply air not mixing properly with the generated aerosol.
Alternative aseptic pharmaceutical filter designs have included the use of additional pre-filter requirements which work to protect the primary filtration media during normal air handling load and during challenging. Prefilters typically are designed to prevent surface loading due to large particles, such as hair, etc. Such pre-filters, however, can foul earlier in the filter life cycle thereby requiring periodic replacement and increased maintenance costs. Such pre-filtering is undesirable in that additional filtration media is therefore required, doubling of maintenance and handling requirements are expected and a lack of efficiency and increased pressure drop result.
Other problems associated with traditional micro-fiberglass HEPA filters are that they are a relatively fragile filter medium which do not react well to handling, in-place contact, vibration, humidity possibly condensing on the filter media or the particle board frames, or chemical exposure. Such micro-fiberglass media may be readily damaged through normal handling. Damage resulting from these various factors can cause leakage and unfiltered air to pass through the media. Further, the filter can fail normal challenging sequences as a result of such damage to the media. Thus, it is desirable to provide a filtering media that meets full HEPA filtration requirements, may be utilized in the aseptic pharmaceutical industry environment, and is more durable for handling and more reliable in remaining fully functional after required integrity tests or challenging sequences and during normal course of operations.
In addition to filter loading, when considering testing of filters with the conventional use of PAO as a challenge aerosol, under certain conditions, bleed through can also be a potential issue. The issue of bleed through may occur when operating a thermal PAO generator at lower pressures to test ePTFE or glass media filters. This is due to the thermally generated aerosol having a 0.10-0.45 mass mean diameter which is closer to the MPPS of the filter. This creates an issue with a photometer measuring a concentration and looking for leaks at or above 0.01%. The bleed through could erroneously manifest itself as an artificially large leak or in some cases a continuous leak across the filter measuring >0.01%.
It is therefore desirable to provide a fully functional HEPA filtration media which meets all requirements, is relatively durable, may be challenged appropriately to determine filtering effectiveness and leakage and which further meets all required aseptic filtration standards. It is further desirable to provide such filtration media without additional pre-filter requirements and with appropriate methodology to determine full functionality of the media and determine possible leakage points without causing fouling of the in-situ filters.
It is also desirable to provide an aerosol generator capable of producing a steady, consistent output of low concentration challenge compound so as to be compatible with the use of discrete particle counters used for leak testing filter media.
Thus, there is a need in the art to provide a fully functional aseptic pharmaceutical filter media which has associated full testing methodology, is durable, maintains HEPA filtration efficiencies and which has a long in-place filtration life.

Aerosol generator for EPTFE filter testing and method of use


A stencil device ensures that solder paste is accurately applied to a printed circuit board to create a substantially zero signal degradation solder bridge electrical connection. The printed circuit board is defined by a dielectric structure core having a first surface which further includes a first conducting pad having an edge and a second conducting edge having an edge separated from and adjacent to the edge of the first conducting pad. The edges of the first and second conducting pads define therebetween a surface area of the first surface. The stencil device includes a stencil plate member defining a first opening sized to substantially correspond to the first conducting pad, a second opening sized to substantially correspond to the second conducting pad, and a third opening. The third opening links the first opening to the second opening at a size to correspond to a partial portion of the surface area of the first surface between the edges of the first and second conducting pads. The stencil device ensures that solder paste flows through the first, second, and third openings onto the first and second conducting pads and the first surface of the dielectric structure core to form a substantially zero signal degradation electrical connection between the first and second conducting pads.

This invention relates to printed circuit boards. In particular, the present invention is a method of fabricating a high signal integrity, "solder bridge" electrical connection for connecting conducting pads of a printed circuit board, and a printed circuit board having at least one solder bridge for electronically connecting adjacent printed circuit board conducting pads. The solder bridge forms a reliable and secure electrical connection between adjacent conducting pads without the need for electronic components such as zero ohm resistors, dip switches and/or jumper block/header arrays.
Printed circuit boards (PCB's) with electrical components are widely used in the electronics industry in a variety of products including computers, televisions and telecommunication devices. PCB's are typically manufactured in a two step process. First, the actual PCB "blank" is fabricated from multiple layers of materials and copper traces. The copper traces typically terminate in conducting through-holes or conducting pads to which electrical components can be attached to the PCB blank. In the second part of the PCB manufacturing process, these electrical components, such as resistors, capacitors, microchips, etc. are attached to the PCB blank. Through-hole electrical components are generally attached to the conducting through holes of the PCB blank using through-hole processes, while surface mount electrical components are attached to the conducting pads of the PCB blank using surface mount processes.
In typical through-hole mounting processes, the leads of the electrical components are passed through the conducting through-holes in the PCB blank so that the ends of the leads extend beyond a bottom side of the PCB blank. The ends of the leads are then soldered to the bottom side of the PCB blank by a solder wave in which molten solder flows across the bottom side of the PCB blank. The molten solder fills the voids between the electrical component leads and the conducting through-holes to form conductive bonds between the leads and the conducting through-holes on the PCB blank.
In typical surface mounting processes, a solder paste is applied to the conducting pads of the PCB blank through a stencil patterned with openings corresponding to the PCB blank conducting pad locations. Typically, the solder paste is screen deposited onto the conducting pads using the stencil as a mask and a blade to squeegee the solder paste through the holes in the stencil. When the stencil is removed, the solder paste remains on the conducting pads of the PCB blank. Next, the leads of the electrical components are placed on the soldered conducting pads, and the solder paste is subjected to reflow soldering to adhere the leads to the conducting pads. To prevent solder shorts (i.e., the unwanted formation of an electrical connection between conducting pads), due to the imprecise application of the soldering paste or the unwanted flow of solder during the reflow soldering process, the conducting pads are often fabricated on the PCB blank so as to have an edge-to-edge conducting pad separation of between 20-100 mils with a minimum edge-to-edge conducting pad separation of at least 12 mils.
During the process of mounting electrical components to the PCB blank, it is often necessary to simply electrically connect conducting pads to one another with acceptable parasitic capacitance and inductance. Typically, to electrically connect conducting pads in this fashion, it is necessary to use a "load/no-load" process to mount a separate electrical component to the PCB blank after the application of the soldering paste and before the reflow soldering procedure. Types of components that are typically used are "zero ohm resistors", "dip switches" and "header array/jumper blocks".
Although any one or all of these components can provide the desired electrical connection between conducting pads there are drawbacks to the use of these types of electrical components. For example, all of these solutions to providing an electrical connection, with acceptable parasitic capacitance and inductance, between conducting pads requires the use of separate electrical components (i.e., extra parts). These extra parts increase the overall cost of manufacturing the PCB. Moreover, these extra parts are susceptible to damage during routine handling of the PCB that may adversely affect the operation of the PCB. In addition, these extra parts are susceptible to becoming dislodged or inadvertently misaligned during the reflow soldering process which can adversely affect the electrical connection formed by these separate electrical components and the subsequent operation of the PCB. Further, these separate electrical components take up valuable PCB surface area and degrade the integrity of the electrical signal between the conductor pads connected by these components. Still further, PCB's employing these separate electrical components are not easily reconfigurable during the PCB manufacturing process, since to accomplish such a task typically requires the addition of automated equipment and/or the reprogramming of automated equipment for mounting these components onto the PCB blank in the desired reconfigured format. Lastly, the design of these separate electrical components limits their PCB mounting configurations, and as such, typically necessitates that these components be mounted to the PCB either parallel (i.e., 180°) or at a 90° angle with respect to other components on the PCB.
There is a need for PCB's having substantially zero signal degradation electrical connections that minimize parasitic capacitance and inductance between connected conducting pads, and a method of fabricating such substantially zero signal degradation electrical connections between conducting pads of a PCB. In particular, there is a need for PCB's having these substantially zero signal degradation electrical connections and a method of fabricating these electrical connections between conducting pads that does not require the use of separate electrical components (such as "zero ohm resistors", "dip switches" and "header array/jumper blocks) and thereby reduces the cost of manufacturing the PCB. These substantially zero signal degradation electrical connections should not be susceptible to damage during routine handling of the PCB that may adversely affect the operation of the PCB. In addition, these substantially zero signal degradation electrical connections should not be susceptible to becoming dislodged or inadvertently misaligned during the PCB manufacturing process. Further, these substantially zero signal degradation electrical connections should not take up valuable PCB surface area, nor should these electrical connections degrade the integrity of the electrical signal between connected PCB conducting pads. Still further, it should be relatively easy to reconfigure the PCB during the manufacturing process to eliminate, add or change the configuration of these substantially zero signal degradation electrical connections without adding automated equipment and/or reprogramming automated equipment for mounting electrical components onto the PCB blank. Lastly, these substantially zero signal degradation electrical connections should be rotatable through any angle so as to be mountable to the PCB at any angle (not just 90° and 180°) to allow the PCB to employ various conducting pad geometries and groupings to take advantage of available PCB surface space.

Stencil device for accurately applying solder paste to a printed circuit board

Hewlett-Packard Development Company, L.P.


A vibrating device has at least one dampening portion. The dampening portion comprises a first tube, a second tube and a layer of resilient material configured so that the first tube is disposed about the second tube, and the layer of resilient material is positioned between the first and second tubes.

Many recreational and work devices transmit vibrations to the user. Most of the time, the majority of vibrations are transmitted to the user's hands and arms when they are holding the device. These vibrations can cause fatigue and discomfort during use and, in some cases, prolonged use of these devices can cause pain or injury to the user. Therefore, it is desirable to reduce the amount of vibrations transmitted to the user.
U.S. Pat. Nos. 6,257,220 and 6,382,301 to McPherson et al. discuss vibration dampers as applied to archery bows, and are incorporated herein by reference in their entirety. U.S. Pat. No. 7,055,276 to McPherson discusses vibration dampers as applied to firearms, and is incorporated herein by reference in its entirety. U.S. Patent Application Publication 2005/0279599 to McPherson discusses vibration dampers as applied to handheld devices, and is incorporated herein by reference in its entirety. U.S. Patent Application Publication 2005/0279598 to McPherson discusses vibration dampers as applied to motorized devices, and is incorporated herein by reference in its entirety.
The art referred to and/or described above is not intended to constitute an admission that any patent, publication or other information referred to herein is "prior art" with respect to this invention. In addition, this section should not be construed to mean that a search has been made or that no other pertinent information as defined in 37 C.F.R. §1.56(a) exists.
All US patents and applications and all other published documents mentioned anywhere in this application are incorporated herein by reference in their entirety.
Without limiting the scope of the invention a brief summary of some of the claimed embodiments of the invention is set forth below. Additional details of the summarized embodiments of the invention and/or additional embodiments of the invention may be found in the Detailed Description of the Invention below.


A voltage regulator includes a pass element having a control input coupled to a control node and operable to generate an output voltage at an output node, a negative feedback amplifier operable to receive a reference voltage and the output voltage and generate a signal at the control node based on a difference between the reference voltage and the output voltage, and a noise cancellation circuit coupled to the control node and the output node and operable to generate a bias current at the control node based on the output voltage.

The disclosed subject matter relates generally to voltage regulation and, more particularly, to feed-forward compensation for a low-dropout voltage regulator.
Voltage regulators are used to provide low noise power supplies for sensitive analog devices in an integrated circuit that is dominated by digital circuits that introduce significant amounts of supply noise. For example, a clock-and-data recovery (CDR) phase-locked-loop (PLL) loop may employ a voltage controlled oscillator that is powered by a voltage regulator. Noise in the voltage supply equates to frequency error and ultimately jitter in the generated clock signal.
A conventional low-dropout (LDO) voltage regulator 100 is shown in FIG. 1. The regulator 100 includes a negative feedback amplifier 105 that feeds a pass element 110 at a control node 112, Vmpg. The output of the pass element 110 drives a load 115 connected to an output node 120 at a predetermined voltage level (VOUT). A feedback path is established through a voltage divider 125 including resistors 130, 135. A capacitor 140 is coupled between the output node 120 and ground to provide high frequency noise rejection. The negative feedback amplifier 105 tracks the difference between the output voltage and a reference voltage, VREF, to control the pass element 110 to reduce the voltage error between the inputs of the negative feedback amplifier 105.
The power supply noise rejection ratio (PSRR) of the conventional LDO regulator 100 is shown in FIG. 2. At low noise frequencies, the negative feedback amplifier 105 can force VOUT to track the input reference VREF. The DC supply rejection is limited by the gain of the feedback amplifier 105 and the differential output resistance of the pass element 110. Once the feedback amplifier 105 becomes bandwidth-limited (at a noise frequency of f1), the PSRR begins to degrade as VOUT can no longer track VREF. This degradation is manifested as a zero in the PSRR response. The PSRR continues to degrade with increasing noise frequency until a frequency f2, where the decreasing impedance of the capacitor 140 begins to take effect. At this point, the PSRR improves as high-frequency supply noise at VOUT is attenuated by the capacitor 140.
LDO regulators are limited in supply rejection across a broad noise frequency bandwidth due to limitations in the bandwidth of the feedback amplifier 105, the feedback amplifier gain, the available area for the large capacitor 140 to suppress supply noise beyond feedback amplifier bandwidth, and the output resistance of the pass element.
This section of this document is intended to introduce various aspects of art that may be related to various aspects of the disclosed subject matter described and/or claimed below. This section provides background information to facilitate a better understanding of the various aspects of the disclosed subject matter. It should be understood that the statements in this section of this document are to be read in this light, and not as admissions of prior art. The disclosed subject matter is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above.

Feed-forward compensation for low-dropout voltage regulator


A method to minimize common rail pressure irregularities due to aliasing effect on battery voltage monitoring in a digital electronic control unit that is capable of PWM (Pulse Width Modulation) regulations of a metering valve unit in a diesel common-rail power-train system. At least an engine rotary speed signal is detected and at least a battery voltage signal is monitored, the method includes, but is not limited to calculating the aliasing frequency on said battery voltage signal as a function of said engine rotary speed signal, filtering the battery voltage signal before it is input to said controller module with at least one digital non-linear notch filter, the at least one digital non-linear notch filter centered about the first harmonic of the aliasing frequency, and input the filtered battery voltage signal, at least with the engine rotary speed signal, to the controller module for PWM regulating the metering valve unit.

In a diesel common rail power-train system, as the one sketched in FIG. 1, great importance has the fuel pressure run in the common rail placed upstream to the engine injectors, in order to assure efficiency and regularity of the engine operation. Such a fuel pressure within the rail is usually controlled by means of an electronic digital control unit that regulates, usually with a digital PWM (Pulse Width Modulation) technique, the metering valve unit controlling the fuel intake in the high pressure pump feeding the rail. The electronic control unit generally receives as inputs at least the monitored (digitized) battery voltage signal and the engine rotary speed signal, properly acquired with known detectors, and provides as output a PWM signal, with a required duty-cycle.
But, as known in the art, in a diesel common-rail power-train system, the battery voltage signal, that for generic purposes might be considered quite flat, is indeed affected by voltage drops and noises that cannot be disregarded when a PWM regulation of a high sensitivity load, such as the metering valve unit, is carried out by an electronic (digital) control unit. In fact, a common-rail power-train system usually comprises a digital control unit for driving a number of actuators, on the basis of digital signals coming from a number of relevant detectors, as well as on the basis of the monitored battery voltage signal. Among the actuators, as already mentioned, the metering valve unit is usually regulated by means of a PWM (Pulse Width Modulation) technique, by a proper controller module.
In such an environment, it should be pointed out that driving of many actuators (e.g., the fuel injectors) in a diesel common-rail power-train system is generally synchronous with the engine position (i.e., with the engine rotary speed) and thus it introduces a generally periodic effect on the battery voltage signal. More in detail, such a generally periodic effect on the battery voltage signal can be described as follows.
The battery voltage drops with conducted and irradiated noise through the electrical circuit of the power-train system generate a periodic ripple that superimposes the voltage mean value of the battery voltage signal, and the first harmonic frequency of the battery voltage signal, which is defined by its mean value plus the periodic ripple, is directly linked to the engine rotary speed.
Aliasing in battery voltage monitoring can thus affect the regulation of the metering valve unit by an electronic control unit, when sampling frequency matches the battery voltage signal harmonic spectrum, thus resulting in possible unduly pressure irregularities (oscillations) within the diesel common rail. In particular, considering a sampling time ts (e.g., 12.5 ms), since the afore-said periodic ripple superimposed on the battery voltage mean value can be considered to be a sub-multiple of the engine cycle period, digitalization of the battery voltage will result in a voltage signal substantially composed by the battery voltage mean value plus a low frequency component, having frequency equal to:
      f    aliasing    =                        1                  t          s                    -              rpm                  k          ·          60                        Where:rpm is the engine rotational speed expressed as revolutions per minute; −k is a constant depending on the cylinder number of the engine, defined as:
  k  =      2          Cylinder                                      number      (e.g., k is equal to 0.5 for a 4 cylinder engine and it is equal to 0.125 for a 16 cylinder engine).
This means that when
            t      s        ≅                  k        ·        60            rpm        ,an additional low frequency component will be generated by aliasing effect, so that the digitalized form of the battery voltage signal will be affected by an equivalent harmonic spectrum not corresponding to the actual battery voltage signal.
In a diesel common-rail power-train system, the regulation of the metering valve unit, which is that valve metering the fuel intake volume to the high-pressure pump of the common rail, may be strongly affected by said aliasing effect in the battery voltage signal, mainly due to the fact that the metering valve unit regulation is carried out by the actuation of a PWM (Pulse Width Modulation) voltage. In fact, as can be easily ascertained, the duty-cycle (D*) of the PWM regulation of the metering valve unit, may be seen as:
      D    *    =            V      MU      *                      V        ~            batt
Where V*MU is the desired mean voltage across the metering valve unit and {tilde over (V)}batt is the theoretical battery voltage (digital) signal.
Since the real battery voltage (Vbatt) can be seen as the sum of the theoretical battery voltage signal {tilde over (V)}batt with its voltage variation due to aliasing noise (ΔValiasing), and the voltage effectively applied (VMU) to the electromagnet of the metering valve unit results as the duty-cycle (D*) multiplied with the real battery voltage, one can easily ascertain that:
      V    MU    =                    D        *            ·              V        batt              =                  V        MU        *            ·                        V          batt                                      V            batt                    -                      Δ                                                                                V              aliasing                                          The mismatch between Vbatt and {tilde over (V)}batt due to the possible aliasing effect will results in an undesired noise affecting the metering valve unit regulation.
Applying the "small signal approximation" one can see that the noise oscillation in the metering valve unit voltage (ΔVMU) can be so approximate:
      Δ                                V      MU        =                    V        MU            -              V        MU        *              =                                        V            MU            *                                V            batt                          ·        Δ                                                    V        aliasing            Such a noise oscillation (ΔVMU) thus affects the metering valve unit regulation with an entity that depends on the proper transfer function used by the relevant controller module in the Electronic Control Unit in order to transform the nominal (desired) fuel intake volume request (Q*) of the high-pressure pump, in a duty-cycle set point for regulating said metering valve unit.
Adopting again the small signal approximation, the close loop scheme reported in FIG. 2 can describe the PWM control unit of the metering valve unit in a diesel common-rail power-train system, affected by the aliasing effect on the battery voltage signal.
In FIG. 2, one can see that Q* is the desired fuel intake quantity request; I(Q): is the I-Q characteristic of the metering valve unit (i.e. the characteristic curve showing the relationship between current (I)—fuel quantity (Q) in the metering valve unit); I*MU: is the electrical current required to meet the fuel intake quantity request (Q*) using a metering valve unit with I(Q) characteristic; ĨMU: is the nominal (theoretical) electrical current absorbed by the electromagnets of the metering valve unit; R(s): is the generic transfer function of the electronic control unit regulating the metering valve unit; V*MU: is the desired mean voltage across the electromagnet of the metering valve unit; ΔVMU: is the noise Oscillation in the metering valve unit voltage; and VMU: is the voltage effectively applied to the electromagnet of the metering valve unit.
In view of above, it should be clear that the voltage oscillation effect can be focused as an equivalent fuel quantity oscillation according to the following equation:
      Δ                                Q      aliasing        =      Q              (                        Δ                                                                          V            MU                                    R                                (            s            )                              )      This leads to the equivalent scheme of FIG. 3.
The applicant has ascertained that ΔQaliasing could reach values up to ˜20÷40 mm3/stroke, with the aliasing frequency of the battery voltage signal ranging from approximately 1 to 3 Hz, resulting in a pressure oscillation on the common rail with a peak to peak magnitude directly proportional to its capacity, up to 15÷30 MPa. Such an undesired pressure oscillation due to the aliasing effect on the battery voltage monitoring, results in certain unevenness in the engine operation when a certain rotational speed of the same engine is reached, with possible bad consequences on the efficiency of the engine, its fuel consumption and performances.
Therefore, at least object is to solve the drawbacks of the actual diesel common-rail power-train system underlined above, by removing, or at least reducing, the aliasing effect on the battery voltage monitoring in a digital control unit for PWM (Pulse Width Modulation) regulations of a metering valve unit in a diesel common-rail power-train system. It is thus at least another object to provide a method to minimize common rail pressure irregularities due to aliasing effect on battery voltage monitoring in a digital control unit for PWM (Pulse Width Modulation) regulations of a metering valve unit in a diesel common-rail power-train system. In addition, other objects, desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.

Method to minimize common rail pressure irregularities due to aliasing effect on battery voltage monitoring


A closure system and various exemplary embodiments for devices including the closure system are disclosed. The closure system may include a base, a sideplate configured to rotate with respect to the base, and a retaining mechanism carried by the sideplate and configured to pivot with respect to the sideplate substantially transverse to an axis of rotation of the sideplate. The retaining mechanism may be configured to engage with a engagement protrusion of the base to prevent rotation of the sideplate. A chest roller, a snatch block, an ascender including the closure system and a method of use of the closure system, are additionally disclosed.

1. Field of the Invention
The present invention relates to a closure system, a method of use of same, and devices including the closure system such as, by way of example, a chest roller, a snatch block, and an ascender.
2. State of the Art
Chest rollers are used for various applications in many different activities. A conventional chest roller 10, depicted in FIG. 1 is typically associated with rope work in vertical terrain, such as caving and rescue work. An individual ascending or descending a free-hanging rope may be secured to the rope with a waist harness, and a chest roller is worn to keep the individual in an upright position, with his or her chest proximate the rope. A baseplate 11 may be affixed to the chest of the individual as by straps or webbing, and the rope will pass through opening 16 and abut sheave 12. As the individual ascends or descends, the chest roller 10 also moves up or down on the rope, and the sheave 12 rotates about an axle or pin (unnumbered) affixed to a pedestal 13 to minimize the friction on the rope. The closure system of the chest roller 10 includes a sideplate 15 which is movable when button 14 is depressed, enabling the rope to be laterally inserted or removed from the opening 16. However, the sideplate 15 is not directly affixed to the baseplate 11, requiring any outward forces on the sheave 12 to be transferred to the baseplate 11 through pedestal 13. The uneven loading on the pedestal 13 by the cantilevered sheave 12 puts additional stress in the form of bending and shear stress on the connection between the baseplate 11 and the pedestal 13.
Carabiners are also conventionally used in roped activities. FIGS. 2A, 2B and 2C illustrate one conventional carabiner 100 in which the carabiner body 60 of the carabiner 100 consists of a single round metal shank formed in a generally C-shape with two ends, a securing end 25 and a receiving end 20. The oblong C-shape of the carabiner body 60 forms a mouth 29 between ends 20 and 25. As further shown in FIG. 2B, a gate 50 is typically a single piece made of heavy round metal wire, having two ends 74, 76. The gate wire is bent to form an oblong shape having a closed U-shaped head 58, a long arm 54 and a short arm 56 which converge upwardly. The ends 74, 76 of the gate 50 are each turned inward at a right angle about a radius to form stems 84, 86, respectively. One of arms 54, 56 is raised with respect to the other arm by being pivoted or twisted at the point connecting the arm to head 58. Accordingly, if gate 50 is placed on a level surface, the head 58 and one arm 54, 56 will lay flat, while the other arm will form an upward angle with the surface. This result will occur regardless of which arm 54, 56 is placed on the level surface.
The securing end 25 of the carabiner 100 is slightly tapered to form flattened, parallel side surfaces, and two linearly adjacent supporting holes 24, 26 are bored therethrough. The diameter of the wire for the gate 50 is substantially smaller than the diameter of the carabiner body 60 so that stems 84, 86 of gate 50 fit into the supporting holes 24, 26, respectively. The stems 84, 86 are of sufficient length to pass into the entire length of supporting holes 24, 26 transverse to the side surfaces, respectively, without extending outside the respective supporting holes 24, 26. Supporting holes 24, 26 pivotally connect the gate 50 with the carabiner body 60 50 that gate 50 may be opened and closed.
In the closed position of FIG. 2A, the gate 50 extends to the receiving end 20 of the carabiner body 60. Since one arm 54, 56 of gate 50 is twisted and supporting holes 24, 26 are linearly aligned, a spring-like, biasing force is created when gate 50 is connected to the securing end 25. Accordingly, head 58 of gate 50 is biased to the closed position against the inside of the receiving end 20 of the carabiner body 60. The gate 50 may thus provide structural support for the carabiner 100 under tensile loading along the major axis 55. As shown in FIG. 2c gate 50 may be opened by applying an inward force on the gate 50. The gate 50 of the carabiner 100 provides a closure system with structural support; however, the gate 50 is prone to an accidental opening because only an inward force in a single direction is required to cause the gate 50 to open.
In view of the foregoing, it appears that a closure system having a quick and straightforward sideplate opening and closing mechanism that may be securely closed is needed. A sideplate configuration adding structural support would also be useful.

Closure system, method of use, and devices including closure system


A method for measuring soil in a wash liquor or other soil-containing liquid medium, the method comprising:                a) a soil sensing step wherein the soil-containing liquid medium is contacted with a plurality of fuzzy-correlated soil-sensing means, each responsive to a distinct physico-chemical soil characteristic and providing one or more soil parameter measurements corresponding thereto;        b) a data processing step wherein the soil parameter measurements for each sensing means are entered as input data into a model algorithm defined on the basis of an algorithm dataset comprising experimental or consumer-generated soil parameter and soil concentration information and which functions to generate predicted soil data of enhanced confidence level; and        c) a communication step wherein one or more signals dependent upon the predicted soil data is issued to an output device, data store, user interface, data processor, or an appliance director or module.

In recent years there has been considerable activity in the field of so-called 'smart' appliances, i.e., household and other appliances which incorporate sensing systems responsive to one or more process or environmental conditions and which operate under the control of a model algorithm so as, for example, to automate some manual function of the appliance, to economize on energy or reduce environmental impact, to optimise the ease of use and performance of the appliance or of an ancillary product, or to provide some new appliance functionality.
Smart appliance technology is finding particular application in the field of cleaning appliances including automatic laundering, dry-cleaning and dishwashing machines, both domestic and commercial. Typical sensors in use today include water level sensors in clothes washers, humidity sensors for automatic dryer control, temperature sensors, turbidity and other optical sensors for sensing wash water soil, conductivity sensors for sensing water hardness or for detecting the type of product being used, position sensors for applications such as dishwasher spray arm position, speed sensors to detect the rotational speed of the clothes drum, torque, inertia and water absorption sensors for use in load and fabric type sensing, and accelerometers to sense vibration caused by out-of-balance loads in washers.
The accurate and reliable estimation of the level and composition of substrate soil is of especial importance from the viewpoint of determining the correct product usage for achieving optimum cleaning, finishing and fabric care performance. Many consumers will decide on the correct dosage to use based on a visual assessment of the soiled items and in particular on the degree of staining of laundry items. Visual assessment often provides a false impression of the degree of soiling however. A stain may make a big visual impact but it could in practice represent a small soil load. Many common body soils on the other hand have low visibility. So often a consumer will overdose product in cases where the soil load is visible but low; or underdose product in cases where the soil load is of low visibility but high.
There is a need therefore to develop model algorithms that can provide a robust and accurate measurement of the soil load in a soil-containing liquid medium or an accurate prediction of the soil load on the soiled article for use in estimating optimum product usage levels. Soil levels and composition are difficult to measure accurately, however, in part because of their varying origin and complexity. No single parameter currently exists that can directly measure soil since it is a heterogeneous substance composed of a multitude of components having differing physical, chemical and biological properties. Using turbidity as a measure of soil, for example, could lead to an inconclusive or inaccurate assessment of the soil load because turbidity only reflects one aspect of the soil. In addition the properties and environmental history of the soil-containing system, for example the water source, water quality, hardness, substrate load, etc can also affect the measurement process and lead to a less accurate prediction of the soil by, in effect, increasing noise and lowering signal-to-noise ratio.
Another aspect of the problem is that of accurately predicting the substrate soil load prior to the cleaning operation and detergent product delivery. Typically the absolute soil level of the clothes has been determined from the steady state saturation value of a turbidity sensor signal and from the time the turbidity signal takes to reach that value from an initial condition at the start of the wash. Reaching a steady state saturation value can take a significant amount of time, however, and it would clearly be advantageous to determine predicted soil levels by a dynamic process whereby the optimum product usages can be determined prior to achievement of a steady state and prior to delivery of the detergent or ancillary products into the cleaning liquor.
Accordingly the present invention provides improved methods using soil sensor-based model algorithm techniques for measuring the soil load in a soil-containing liquid medium and for estimating the soil load on the soiled article for use in predicting optimum product usage levels and other dosage-related control parameters.

Abstract: The invention also relates to methods for measuring the degree of soiling of a soiled article, and methods for cleaning a soiled article in a wash liquor or other liquid medium.


Antilock control system wherein pressure at the front and rear axles is controlled in cycles which each include a pressure reduction followed by a build-up of the brake pressure in pulses having holding phases therebetween. When a build-up of brake pressure at the front axle exceeds a predetermined time, the rate of build-up at the rear axle is reduced. The system prevents too much pressure build-up at the rear axle during the dynamic load transfer which occurs when braking a vehicle having a high center of gravity relative to its wheel base.

In vehicles with an unfavourable ratio of the height of the centre of gravity to the wheelbase, extreme dynamic axle load transfers lead to a marked relief of the load on the rear axle, particularly in the case of high decelerations. If this state of affairs is not taken into account, a rear-axle pressure build-up decoupled from the vehicle deceleration and from the pressure level of the front axle leads inevitably to vehicle instability.
From DE-OS 2,215,608 (GB-A 1,376,581) it is known that, in vehicles equipped with an ABS and having a high centre of gravity and a short wheel base, overturning can be avoided by not permitting an excessively large difference of the brake pressures at the front and at the rear. If this difference exceeds a predetermined magnitude, the pressure at the front is not increased further.

ABS control with rear pressure rate reduction when front pressure and time conditions are met


Apparatuses, systems, and methods for reset of row hammer detector circuits. A row hammer detector circuit includes a hash circuit configured to store a hash key and provide a first count value based on a hash between the hash key and a row address corresponding to a row of memory cells of a memory array. The row hammer detector circuit is configured to provide a match signal in response to the count value exceeding a threshold to cause a targeted refresh of a victim row adjacent the row of memory cells. In response to exit from a self-refresh mode, the hash circuit is configured to update the stored hash key with a new hash key.

This disclosure relates generally to semiconductor devices, and more specifically to semiconductor memory devices. In particular, the disclosure relates to volatile memory, such as dynamic random access memory (DRAM). Information may be stored on individual memory cells of the memory as a physical signal (e.g., a charge on a capacitive element). The memory may be a volatile memory, and the physical signal may decay over time (which may degrade or destroy the information stored in the memory cells). It may be necessary to periodically refresh the information in the memory cells by, for example, rewriting the information to restore the physical signal to an initial value.
As memory components have decreased in size, the density of memory cells has greatly increased. Repeated access to a particular memory cell or group of memory cells (often referred to as a 'row hammer') may cause an increased rate of data degradation in nearby memory cells. Memory cells affected by the row hammer effect may be identified and refreshed as part of a targeted refresh operation.

Apparatuses, systems, and methods for resetting row hammer detector circuit based on self-refresh command


A system and method for obtaining and maintaining synchronization with an incoming signal prior to and during the transmission of data. Specifically, embodiments of the present invention contemplate that synchronization is obtained by searching for an initial portion of a pattern in an input signal. Once the pattern is detected, the pattern (and/or some mathematical derivation thereof) must subsequently be detected a pre-determined number of times. Once synchronization has been obtained, a pattern is continually looked for in the input signal in order to maintain synchronization. The present invention maintains this synchronization even though data may be embedded within this input signal.

I. Field of the Invention
The present invention relates to obtaining and maintaining synchronization with an incoming signal prior to and during the transmission of data. More specifically, the present invention relates to recognizing that a pattern within an incoming demodulated electromagnetic signal has repeated itself (or that some mathematical relationship thereof has been received) a specified number of times, indicating that synchronization has been achieved and that transmitted data is forthcoming. The present invention also more specifically relates to maintaining synchronization with the incoming demodulated signal while data, which is imbedded within the signal, is received.
II. Related Art
The ability to transmit and receive information using a wireless electromagnetic carrier (at, e.g., radio or microwave frequencies) has been known for many decades. A somewhat more recent development, though, is the ability to receive and process binary data using digital technology. One common way that this works in a wireless environment is that an electromagnetic "pattern" is transmitted representing a binary piece of data (i.e., a binary 1 or 0). This pattern transmission may utilize amplitude, frequency or phase modulation.
The constituent pieces of the pattern themselves represent binary values. Thus, a pattern representing several binary values are used to represent a single binary value of data. For example, receipt of the pattern "10111011" may represent the receipt of "011 as data, while its inverse, 1101000100" may represent receipt of "1. " Data is conveyed in this way because of noise and interference associated with wireless transmissions. Otherwise, it would be difficult to determine whether the receipt of a single binary value was data or just noise.
Information on the electromagnetic carrier is thus received as a stream of representative binary 1's and 0's. Each binary 1 or 0 is known as a "chip." Thus, the data being transmitted is in the form of a pattern of chips. It is desirable that a pattern representing a binary piece of data comprise a significant number of chips to reduce the chance that unwanted noise in the electromagnetic information is mistaken for transmitted data.
Applications utilizing the transmission of digital information have become very popular in recent years. One such application which has been getting wide-spread attention is wireless local area networks (wireless LAN's). This technology allows computers to exchange information with each other by transmitting this information as described above. The obvious advantage that wireless LAN's have over other LAN's is that wires are not needed to connect the computers together.
Because the airwaves are already very crowded and heavily used by a variety of technologies, it is difficult to assign a usable band of frequencies for use by wireless LAN'S. Consequently, spread-spectrum technology is often utilized. This technology (which was originally developed for military applications) allows an electromagnetic transmission to be spread throughout many different frequencies which are already assigned to such technologies as radio or microwave devices. Since spread spectrum signals have a low-power spectral density, they generate less interference to other devices tuned to the same frequency.
Spread spectrum technology and wireless LAN's are particularly applicable to notebook and other small portable computers, as these computers are typically purchased for mobility. However, because of their smaller size and dependency on batteries for power, it is important to minimize the amount of circuitry used in receiving the different frequencies. In addition, because of the competitive nature of the computer industry, it is also important that costs associated with spread spectrum devices associated with wireless LAN's be kept to a minimum.
As indicated above, noise and interference are a problem whenever information is transmitted by electromagnetic means. Because of this problem, two important issues must be resolved for data to be successfully received. The first is that the received information needs to be initially recognized as valid information as opposed to noise. This recognition of valid information is known as "synchronization." During this initial synchronization the information acts as a header to indicate that data is about to be received. The second issue is that once synchronization has been obtained, it must be maintained while data is transmitted. This typically involves maintaining alignment of the received information with a reference signal.
Of relevance to both these issues are two general methodologies for determining whether synchronization has been obtained as is being maintained. The first is to analyze the incoming information on the modulated electromagnetic carrier for synchronization purposes prior to converting the information into digital form. The second is to first demodulate the information (i.e., remove the information from the electromagnetic carrier), convert it into digital form and then analyze the digitized information. The advantage of the latter methodology is that it produces a more cost-effective and compact design. Unless stated otherwise, this is the methodology assumed in use in the discussions below.
Regarding the first issue of obtaining synchronization, as indicated above the transmitting source typically transmits a synchronizing header comprising some pre-determined pattern. The received transmission is compared with a reference code (also comprising the pre-determined pattern). A match of the received transmission and reference code indicates that the header has been received and that data is about to be transmitted. The longer the pattern, the less likely it will be mistaken for noise or interference.
Although a longer pattern is obviously preferable, the problem is that the number of components (and thus the size of the circuit) required to detect synchronization increases nearly exponentially as the length of the pattern increases. When dealing with size, cost and power consumption constraints as discussed above, use of a long pattern can quickly become uneconomical.
Consequently, what is needed is a scheme to utilize an adequately long pattern to minimize false detection while also keeping the size of the synchronization detecting circuitry to a minimum. In addition, the circuitry needs to work in an environment where the incoming electromagnetic information has been demodulated first.
Once the demodulated information from the electromagnetic carrier (hereafter referred to as the "input signal") has been synchronized, then data is received. As indicated above, maintaining synchronization of the input signal as data is received is the second important issue which must be resolved to successfully receive the data.
Also as indicated above, typical schemes for conveying data transmit patterns where each pattern represents a 1 or a 0. The patterns used to transmit data are usually (but not always) longer than ones used for obtaining synchronization. However, the mere comparison of a pattern used to transmit data with a reference code in the manner described above is insufficient for maintaining synchronization. This is because fine adjustments are typically made to realign the input signal. This requires determining whether the input signal is being transmitted too quickly or too slowly, which is not deducible from just a pattern comparison.
Schemes which utilize patterns of an input signal to maintain synchronization during data transmission consequently use a somewhat different approach from that used to initially obtain synchronization. One such scheme for maintaining data synchronization utilizes what is known as a delay lock loop. Although this scheme is conventionally used prior to demodulation, it is discussed below in conjunction with FIGS. 1A and 1B with regard to a binary post-demodulation environment.
Referring first to FIG. 1A, a diagram of a conventional delay lock loop is shown. In operation, an input register 102 receives an input signal via line 100. The input register 102 is divided into two sections (124 and 126), each of which contains a chip received from the input signal. The chips shown in input register 102 represent the chips that are in the input register 102 during a time period t.sub.c.
It is contemplated, time period t.sub.c is the time between when a single chip is first detected (in a reference code presumed in substantial alignment with the input signal as discussed below) and the time that the next chip is subsequently detected. Thus, as shown in FIG. 1A, in roughly the first half of time period t.sub.c, section 124 contains chip N while in the second half of that time period it contains chip N+1. Similarly, in the first half of time period t.sub.c section 126 contains chip N-1 while in the second half it contains chip N. Thus, section 124 can be said to contain a later-in-time portion of the input signal while section 126 can be said to contain an earlier-in-time portion. In time periods subsequent to t.sub.c, input register 102 would contain chips N+2, N+3, etc.
A reference code is generated by a code generator (not shown) and transmitted via a line 104. This reference code comprises the same pattern of chips used to transmit the input signal. Thus, it is expected that the chips received by the input signal are the same as the chips of the reference code. In this example, chip N is transmitted by the reference code during time t.sub.c.
During the time period t.sub.c, whatever chips are in sections 124 and 126 are multiplied with chip N of the reference code. Specifically, the reference code is multiplied with the chip in section 124 using multiplier 108 and the reference code is also multiplied with the chip in section 126 using multiplier 110. Typically, multi-sampling would occur where several multiplications actually take place during the period t.sub.c. Although 1's and 0's are actually multiplied, it is conceptually easier to envision 0's as -1's. Consequently, since [reference code chip] N.times.(input register chip) N=1, and [reference code chip]N.times.(N+1 or N-1) would have a 50--50 chance of equaling a 1 or a -1, then if the input signal is aligned with the reference code the number of 1's resulting from multipliers 108 and 110 should be about the same over a given period of time.
If, however, the input signal is not aligned (i.e., not synchronized) with the reference code, then during time period t.sub.c, chip N will be located in either section 124 or section 126 of input register 102 for a longer period of time than in the other section. For example, if the input signal is running more slowly (i.e., it is "late") as compared with the reference code, then chip N will be located in section 124 for a longer period of time than in section 126. If multi-sampling is used within time t.sub.c (and also when subsequent time periods are looked at) then multiplier 108 will yield more 1's than multiplier 110 during this time period. Conversely, if the input signal is running more quickly (i.e., it is "early") as compared with the reference code, then multiplier 110 will yield more 1's than multiplier 108.
Another way of looking at this concept is now described with regard to FIG. 1B. Referring to FIG. 1B, the chips within input register 102 are shown aligned with each other and with the reference code during time period t.sub.c. If the input signal is received too quickly with respect to the reference code, the input signal would "shift" to the right. Therefore, chip N of the reference code would be multiplied with chip N via the "early" part of the input signal (in section 126) more frequently than with chip N via the "late" part of the input signal (in section 124). Thus, more 1's would result from multiplier 110 than from multiplier 108. The greater the difference in 1's, the greater the misalignment.
Thus, the values of the multipliers can be used to determine the direction as well as the magnitude of any misalignment between the input signal and the reference code. However, because of the random nature of the products generated by multiplying N.times.-1) and N.times.(N+1) as discussed above, some scheme is also typically used to average or "smooth" out the results of multipliers 108 and 110 so that a more accurate assessment of the alignment situation can be determined. Such a scheme is explained with regard again to FIG. 1A.
Referring back to FIG. 1A, an adder 112 adds the values from multiplier 108 and multiplier 110. It is contemplated that the adder 112 yields a positive sign if the results of multiplier 108 are positive and a negative sign if the results of multiplier 110 are positive. In this way, a signed value is generated corresponding to whether the input signal is running earlier or later than the reference code.
An integrator 114 is then used to actually "smooth out" what would otherwise appear as "noisy" signals. Consequently, the integrator typically obtains its output value by sampling the input signal over many chips. The output of the integrator 114 thus indicates an average of both the direction and magnitude of misalignment of the input signal. This output is then typically used to adjust the rate of the reference code to bring it into alignment with the input signal so that synchronization can be maintained.
A problem arises with conventional delay lock loops in post-demodulation environments, however, when data is embedded in the input signal. This is because the data is embedded by inverting the pattern in which the signal is sent. In other words, a non-inverted pattern might be equivalent to a binary 0 while an inverted pattern might be equivalent to a binary 1. The effect of this is that the data affects the ability of the reference code to match the pattern of the input signal. More specifically, many of the chips in the input signal will no longer be the same as the corresponding chips in the reference code. Because of this, synchronization cannot be maintained due to changes in the pattern due to data.
Another problem with conventional delay lock loops is that the electromagnetic waves transmitting the data may be using phase modulation. The results of this is that the input signal may have been inverted during transmission. If that is the case, then any misalignment readings will also be inverted (i.e., a "late" input signal will be interpreted as an "early" one).
Consequently, what is needed is some scheme to detect the direction of a misalignment of an input signal with regard to a reference code regardless of whether data is embedded in the input signal, and regardless whether the input signal has been inverted due to phase modulation.

System and method for obtaining and maintaining synchronization of a demodulated signal

Toshiba America Information Systems, Inc.


A byte-wide memory has a plurality of redundant columns. Each redundant column is capable of being mapped to any one of a plurality of input buffers and output buffers in place of a defective column. Fuse match logic circuits store the addresses of defective columns. I/O fuse decoder circuits are coupled to the fuse match logic circuits and store information identifying the input and output buffers associated with each defective column. The redundant columns are selected in response to a portion of the column address signals which select nonredundant columns. When a received column address matches a stored column address, the redundant column selected by the portion of column address signals is mapped to the input and output buffer associated with the defective column in place of the defective column.

This invention relates to semiconductor memory devices. More particularly, this invention relates to a byte-wide semiconductor memory device having redundant columns which are mappable to input and output buffers at any one of a plurality of bit positions.
Semiconductor memory devices are often provided with redundant columns to improve manufacturing yields. The redundant columns can be programmed to replace columns having defective cells thus permitting the use of a memory device which would otherwise have to be discarded. For byte-wide semiconductor memory devices, that is devices which can input or output plural bits of data simultaneously, it is desirable that redundant columns be capable of replacing defective columns at any bit position.
One method of implementing column redundancy in a byte-wide memory device is to add a single redundant column to each bit position. In such a scheme, each redundant column can replace only a single defective column in the plurality of columns associated with that particular bit position. This technique consumes a great deal of space and is inefficient since it is highly unlikely that a defective column will be associated with each bit position. In addition, this technique is incapable of repairing memory devices having more than one defective column associated with a single bit position.
Another technique for providing column redundancy in a byte-wide memory device is described in U.S. Pat. No. 4,601,019 to Shaw et al. According to the technique described in that patent, each redundant column can be substituted for any defective column in half of an array regardless of the bit position at which the defective column is located. A separate redundancy select circuit is connected to each redundant column and stores address information corresponding to a single defective column. When a match occurs between an externally received column address and a defective column address stored in one of the redundancy select circuits, the redundant column connected to that redundancy select circuit is substituted for the defective column. Although more efficient than the previously described technique, the fact that each redundant column has a separate redundancy select circuit requires more space and a layout which is more complex than desirable.
Accordingly a need exists for a byte-wide memory device having redundant columns and associated control circuitry which require a minimum of space in which the redundant columns are capable of being mapped to any input and output buffer in order to replace defective columns at any bit position.

Memory with I/O mappable redundant columns


A reminder device includes a case sized so that said case is adapted to be worn on the wrist of a user. The case holds a microprocessor, a tactile alarm, an electric clock, and a battery which provides electric power to the microprocessor, the tactile alarm, and the electric clock. A display on the case displays from time to time (a) a pay attention notice alerting the user to be attentive, and (b) one of a plurality a pre-programmed reminder messages. A control panel enables the user to select a periodic interval at which the pay attention notice is displayed, the desired pre-programmed reminder message displayed, and the day and time at which the pre-programmed reminder message is displayed. The alarm is activated when the pay attention notice is displayed and when the pre-programmed reminder message is displayed.

1. Field of the Invention
This invention relates to electronic reminder devices used by individuals with Attention Deficit Hyperactivity Disorder (ADHD) and related difficulties.
2. Background Discussion
There are approximately ten million adults and children in the United States with Attention Deficit Hyperactivity Disorder (ADHD). Individuals with this disorder suffer from a short attention span accompanied by distractibility, forgetfulness, hyperactivity, and impulsivity. Many of these individuals take medication for their ADHD and require accommodations at their school or work. Their forgetfulness and lack of attention results in forgetting to take their medication, losing track of their school work, daydreaming, and general inability to stay on task. Parents, spouses, and teachers attempt to remind them of these tasks, but they are unable to do so on a constant basis.
Several devices have been developed to assist children with ADHD. These devices are cumbersome and generally designed to be placed on a student's desk or belt. One of these devices requires intervention by an observer to activate a visible and audible warning, creating almost as much disruption as manual intervention. Another device periodically vibrates as a reminder, but provide no indication of what the reminder is for. These devices are noticeable to others, resulting in a negative social stigma often associated, are disruptive, and have limited effectiveness.


The purpose of the present invention is to provide an assembled battery including a battery holder capable of holding single battery cells while automatically aligning the cells during assembly. In the assembled battery (100) according to the present invention, a plurality of single battery cells (101) arranged in a row and battery holders (144) disposed between the plurality of single battery cells (101) are held in a state of being mutually pressed in an arranged direction. The battery holders (144) include a positioning means (144f, 144g) that positions the single battery cells (101) by biasing the single battery cells (101), while being pressed in the arranged direction, in a direction intersecting the arranged direction.

As a background technology for the present technical field, there is JP 2011-034775 A (Patent Literature 1). In this publication, it is described that "a separator includes an upper surface holding portion holding an upper surface, a pair of side surface holding portions holding side surfaces, and a lower surface holding portion holding a lower surface of square batteries, and an insulating portion extending between the square batteries. The lower surface holding portion, which is positioned on the cooling surface side, is formed with a cutout portion exposing surfaces of the square batteries on the cooling surface side except for a pair of corner portions in the surfaces on the cooling surface side of the square batteries. A heat-conducting sheet is abutted on a cooling surface of the assembled battery via the cutout portion, with a cooling plate abutted on the heat-conducting sheet (see the Abstract).


A manufacturing process for sheet or shaped work products includes advancing the work product in a direction along a processing path; establishing a reference line with respect to the processing path; capturing visual data related to the work product; converting the visual data into a pixel array; and setting a predetermined line of pixels to correspond with the reference line.

Continuously manufactured products, can include profile shapes and web materials. Profile shapes may take many forms such as tubing, hose, pipe, and plastic lumber with dimensions such as 2×4's and 4×4's, while web materials are typically a continuous sheet of material of a given width. Profiled shaped materials can be any shape, but are usually elongated products with cross-sections that are generally square, rectangular, or circular. Looking down the length of the product, the profile shape can have four walls that define a square (or rectangle), with a hollow center. The opposing walls generally will have equal cross sectional lengths and each wall will usually have an equal thickness measured from the inside surface of the wall to the outside surface or outer periphery of the wall.
For example, 4×4 extruded polymer lumber may be of any length, but the width and depth are generally both 4 inches, measured about the perimeter. Thus, the product has four sides that are all equal in length (hence 4×4), and each side has a thickness (which is generally uniform for all the walls).
A continuously formed product with a shaped profile generally begins in liquid form (or amorphous solid) as a result of heating in an extruder. The raw material is introduced to the extruder in pellet form. An exit orifice of the extruder includes a center shape called a mandrel and an adjustable outer ring called a die. These two objects can have a discernable space between them and the extruder injects the liquefied product material through the space. When the liquefied product is properly cooled, it can form a desired shape of the final work product. The mandrel can define the inner walls of the product and the die can define the outer walls of the product. As the desired shape is acquired, the amorphous solid material can be sent into a cooler for hardening.
The work product can move through these operations by use of a pulling device. The pulling device can be located toward the end of the manufacturing process, and can pull the hardened product down the processing line. One concern in this process is maintaining a desired shape and wall thickness for each side of the product. Wall thickness can be increased or decreased by changing the speed of the pulling device. Similar to stretching a piece of bubble gum, by increasing the speed of the pulling device, the amorphous portion of the product will typically stretch, thereby reducing the wall thickness of the final product. Alternatively, slowing the pulling device speed can increase the wall thickness of the final product.
While the pulling device has the ability to increase or decrease the wall thickness by changing speed, a pulling device can generally only simultaneously change the thickness of all sides of the product. Therefore, if one side has an appropriate thickness, but another side does not, the pulling device will generally be of little value. Similarly, measuring the wall thickness can be a difficult task, as many measuring devices require contact with the product, and others do not provide accurate readings.
Web materials can be made of any of a plurality of materials including paper, plastic, carpet, or other materials. Web materials (as well as shaped profiles) may have a plurality of different components that need measurement and adjustment for quality control and cost management. These components can include length control, width control, wall thickness control, coating thickness control, film thickness control, and opacity control.
Historically, nuclear measurement devices, ultra sonic sensors have provided measurement and control of the dimensions of continuously formed work products such as web materials and shaped profiles. While these techniques can have benefits, they also have drawbacks. With shaped profiles, this measurement is generally taken on cylindrical pipe and some non-cylindrical tubing because of the symmetry of the products. Shaped profiled work products that have sharp angles and several sides, such as continuously formed lumber products, do not easily lend themselves to sensors that usually contact the product to measure wall thickness. Using a single sensor to measure wall thickness of any multisided object usually can be unreliable. In addition, contact by the sensor against the surface of the product has the potential to alter the position or shape of the product, thus decreasing the sensor's accuracy.
Additionally, there is often difficulty in the manufacturing process due to misplacement of the die with respect to the mandrel. This can result in varying wall thickness of each side of the work product. As stated above, work products having continuously manufactured walls of different thickness usually renders the pulling device unable to effectively correct wall thickness errors.
Further, additional problems can occur during other types of production activities. With continuously manufactured products, such as sheet materials and shaped profiles, defects may exist on the material during manufacture. The defects can occur in any of a variety of ways including dimension defects, coating thickness defects, film thickness defects, and opacity defects. One problem that exists is locating the irregularity of the work product so that a correction to the production process can be made
Thus, a heretofore unaddressed need exists in the industry to address the aforementioned deficiencies and inadequacies.


A system that generates risk values for a print service provider. The print service provider may calculate probabilities of an event occurring, calculate the effect that the given event will have on the print service provider, and determine various risks associated with calculations. These risks may then be utilized to determine overall operational strategies for the print service provider when compared to threshold risk levels for the print service provider.

This section is intended to introduce the reader to various aspects of art, which may be related to various aspects of the present invention that are described or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Despite the onset of the "electronic age," there is still significant demand for print products. Indeed, commercial print often may have annual retail sales totaling more than $700 billion. Print service providers (PSPs) fulfill the demand for print products by printing a vast array of print products, such as photographs, brochures, school course materials, periodicals, books, advertisements, and/or product packaging. Once a job order is released to the PSP floor for production, it goes through four stages of production (Pre-press, Press, Post-Press, and Shipping.) As automated gathering of process information through each of these stages increases, information relating to each stage of production becomes more readily available. Accordingly, there is a need to develop systems and techniques to utilize this information to allow for more efficient processing of print jobs.

Print service provider risks applied to decision making


A three-electrode longitudinally-coupled-type SAW resonator filter has an improved level of selectivity by effectively suppressing unwanted large spurious responses generated in a range higher than the pass band. A first ID electrode, a second ID electrode and a third ID electrode are disposed on a piezoelectric substrate. Reflectors are provided on one side of each of the second and third ID electrodes, respectively. A center distance L.sub.1 between the most adjacent electrode fingers of the respective first and second ID electrodes is differentiated from the center distance L.sub.2 between the most adjacent electrode fingers of the respective first and third ID electrodes. Further, the first ID electrode is weighted to more effectively suppress undesired spurious responses.

1. Field of the Invention
The present invention relates to a longitudinally-coupled-type surface-acoustic-wave (SAW) resonator filter in which reflectors are provided at both sides of a region where interdigital electrodes are located. More particularly, the invention relates to the above-described type of longitudinally-coupled-type SAW resonator filter having an improved electrode structure in which unwanted spurious responses are suppressed.
2. Description of the Related Art
SAW filters are being used as band-pass filters for various types of communication devices. It is critically important that band-pass filters ensure required pass bandwidths with high selectivity. Accordingly, it is also required that a SAW filter used in a high-frequency stage reliably provide a required pass bandwidth with high selectivity. It is particularly important that RF-stage SAW filters used in cordless telephones having CT-1, CT-1.sup.+, and CT-2 standards obtain attenuations in ranges of .+-.20 MHz and .+-.40 MHz away from the center frequency, though these ranges vary depending on the intermediate frequency (IF) filters used in the telephones. Thus, the RF-stage SAW filters are required to have even higher selectivity characteristics.
On the other hand, resonator-type SAW filters are advantageous compared to other types of SAW filters in terms of decreased insertion losses and increased out-of-band attenuations and also provide a more compact filter. For example, certain types of longitudinally-coupled-type SAW resonator filters are connected in a plurality of stages to sufficiently satisfy the foregoing requirements. In this type of SAW filter, three interdigital (hereinafter referred to as "ID") electrodes are arranged in proximity with each other at an equal pitch on a 36.degree.-Y-cut X-direction-propagating LiTaO.sub.3 piezoelectric substrate, and reflectors are disposed at both sides of a region where the ID electrodes are located.
However, in the foregoing conventional longitudinally-coupled-type SAW resonator filter, unwanted spurious responses are generated in a frequency range higher than the pass band. FIG. 3 illustrates the attenuation-vs.-frequency characteristics of a known longitudinally-coupled-type SAW resonator filter. The solid line A indicates an enlarged essential portion of the characteristics represented by the solid line B with a scale on the right side of the vertical axis of FIG. 3. The longitudinally-coupled-type SAW resonator filter having the characteristics shown in FIG. 3 has a pass band from 864 to 868 MHz. In the above-described characteristics, large spurious responses indicated by the arrow C appear in a frequency range higher than the pass band, i.e., in the vicinity of 890 MHz, where a sufficiently large attenuation cannot be obtained.
A method for suppressing the above-described spurious responses C is disclosed in Japanese Unexamined Patent Publication No. 8-191229. This method includes a technique for differentiating a distance between a center ID electrode and one peripheral ID electrode from a distance between the center ID electrode and the other peripheral ID electrode. The longitudinally-coupled-type SAW resonator filter disclosed in this publication is shown in FIG. 4.
A longitudinally-coupled-type SAW resonator filter generally indicated by 10 has a structure in which a first ID electrode 14 and second and third ID electrodes 12 and 13 are arranged side by side on a piezoelectric substrate 11 in the direction in which a surface wave propagates. More specifically, the second and third ID electrodes 12 and 13 are respectively disposed at oppositeg sides of the first ID electrode 14. Reflectors 15, 15 are disposed at one side of the ID electrode 12 and at one side of the ID electrode 13, respectively, in the surface-wave propagating direction.
The second and third ID electrodes 12 and 13 are connected to an input terminal 21, while the first ID electrode 14 is connected to an output terminal 22. A voltage is applied to the ID electrodes 12 and 13 to generate a surface wave. The excited surface wave is then trapped in a range between the reflectors 15, 15 to generate a standing wave, and an output in accordance with the standing wave is extracted from the first ID electrode 14.
In the SAW resonator filter 10, the distance between the first ID electrode 14 and the second ID electrode 12, i.e., the center distance L.sub.1 between the most adjacent electrode fingers of the respective ID electrodes 14 and 12, is differentiated from the distance between the first ID electrode 14 and the third ID electrode 13, i.e., the center distance L.sub.2 between the most adjacent electrode fingers of the respective ID electrodes 14 and 13.
However, when the SAW resonator filters 10 illustrated in FIG. 4 are connected in two stages, the following problem occurs. In this filter 10, the center distances L.sub.1 and L.sub.2 are differentiated, which thereby generates an attenuation pole designated by the arrow F in FIG. 5 in a range higher than the pass band where a large attenuation can be obtained. On the other hand, the foregoing large unwanted spurious responses C can only be slightly suppressed and are not sufficiently prevented, as indicated by the attenuation-vs.-frequency characteristics illustrated in FIG. 5. In FIG. 5, the solid line D represents an enlarged essential portion of the characteristics indicated by the solid line E with a scale on the right side of the vertical axis of FIG. 5. Upon comparison of FIG. 5 with FIG. 3, it is seen that the unwanted spurious responses C are not significantly reduced.

Surface acoustic wave resonator filter with a weighted asymmetrical interdigital electrode


Use of a single line for switching multiple monitoring elements on/off, and a single line for sending signals to, or receiving signals from, those elements that are switched on. Monitoring elements each have an associated switching element, and each switching element is connected to a common switching line, or control line. A signal from the control line turns each switch on or off. Each monitoring element is also connected to a single signal line, and only those monitoring elements that are turned on can transmit/receive data signals along this signal line.

The diagnostics and monitoring of structures, such as that carried out in the structural health monitoring field, are often accomplished by employing arrays of monitoring elements such as sensors, actuators, and/or transducers. While many advances have been made, the field continues to face challenges. For example, such arrays often require large numbers of monitoring elements in order to be effective, as structures often must have a variety of sensing elements placed at various locations for accurate monitoring. Because individual sensing elements must often be placed separately, affixing a large array of such sensing elements can be tedious and time consuming. In addition, as each individual sensing element can require one or, commonly, multiple wires, large arrays of sensing elements can require a large number of individual wires, which may be difficult to handle and keep track of. The securing of such large numbers of wires can often be painstaking and time consuming, as well. It is therefore desirable to reduce the number of wires used in arrays of structural health monitoring elements.

Method and apparatus for switching among elements of a structural health monitoring system


A multiplier, which is capable of processing a multiplication of multi-valued data, includes a register transforming circuit (RC) for shifting data stored and outputting a plurality of data, a multiplying circuit connected to the register transforming circuit (RC) for multiplying the outputs from the register transforming circuit (RC) and an adding circuit connected to the multiplying circuit for adding the multiplied results according to a predetermined arithmetic rule based on logic to be used. The multiplier further includes an AND circuit element connected to the adding circuit for shifting and sending out the outputs from the adding circuit. A W register is connected to the adding circuit for storing the shifted outputs from the adding circuit according to the AND circuit element, and a further AND circuit element is connected to the W register for shifting and sending out the outputs from the W register. Another AND circuit element is connected to the further AND circuit element for further shifting the outputs from the further AND circuit element. Finally, a W register is connected to the further AND circuit element for storing the shifted output from the W register.

1. Field of the Invention
The present invention relates to a multiplier which may suitably apply to processing data such as image data, data from a communication signal or fonts used in a laser printer. More particularly it relates to a multiplier which may process multi-valued signals such as binary signals or quadruple signals.
2. Background of the Related Art
In general, it is known that a multiplier is one kind of arithmetic and logic unit used in an electronic computer and is dedicated to multiplication. Herein, the term "multiplication" means deriving a partial product of a multiplicand and each part (one or more bits) of a multiplier and adding the derived partial products to one another.
The multiplication is built as a standard function in the recent computer. To improve the operating performance, several kinds of methods have been developed. As one method for enhancing the operating performance (speed), the Booth algorithm can be used. The Booth algorithm is arranged to reduce the number of units for producing a partial product and make the arrangement of each unit simpler. As another method, the Wallace tree can be used. The Wallace tree uses a tree for making the additions of partial products as parallel as possible, thereby reducing the necessary adding time.
As another method for a very large scale integrated circuit (VLSI), a method has been used where the used fundamental circuits are arranged in a two-dimensional regular array format. A so-called array multiplier corresponds to a multiplier using this method.
However, all of the above-mentioned multiplying methods have a disadvantage in that they cannot theoretically yield a long enough time margin to rapidly and stably perform a multiplication.
Furthermore, those serial or parallel multiplication methods have a disadvantage in that they cannot be used for both of a binary signal and a quadruple signal and cannot perform a rapid multiplication.

Multiplier for processing multi-valued data


The invention relates to methods of detecting a drug resistant HIV in a subject. The methods include detecting mutations associated with drug resistance in an HIV 2-LTR circle DNA molecule obtained from a cell of an HIV-positive subject, e.g., an HIV-1-positive human.

Various assays have been developed to detect HIV. A common HIV-1detection assay utilizes quantitative polymerase chain reaction (PCR) as a means to amplify and detect viral RNA present in patient plasma. HIV-1positive individuals undergoing combination antiviral therapy (i.e., receiving two or more anti-HIV-1compounds) can exhibit decreased viral loads in the peripheral blood. In some cases, after several weeks or months of therapy, HIV-1RNA cannot be detected in the peripheral blood, indicating possible eradication of HIV-1in those individuals. Unfortunately, if patients exhibiting such a seemingly negative result stop therapy in the face of continued viral replication below the sensitivity of detection assays, the HIV can rebound very rapidly. Thus, the limited sensitivity of HIV detection assays provides a challenge to further advances in therapy.
Highly active antiretroviral therapy (HAART) with reverse transcriptase and protease inhibitors markedly suppresses HIV replication in the majority of infected patients. However, in a significant percentage of patients, viruses acquire mutations in their reverse transcriptase and protease genes that confer decreased sensitivity to the reverse transcriptase and protease inhibitors. This leads to drug failure, a resumption of viral replication, and a negative impact on patient survival. To combat drug resistance, clinicians switch therapies to drug combinations not previously administered to the patient. However, drug resistance mutations can confer resistance to a broad spectrum of reverse transcriptase and protease inhibitors. More effective clinical management of patients is achieved if the drug-resistance mutations are identified early so that treatments can be adjusted to those that are effective against the particular strain (e.g., mutant) of HIV. In view of this, viral genotyping is becoming an established procedure for monitoring of patients on HAART and has a significant impact on patient survival.
Viruses bearing drug-resistance mutations cannot generally be identified unless they comprise a significant percentage of a patient's viral population. As a consequence, the drug-resistant viruses are usually identified relatively late in the process leading to drug failure. Therefore, there is an urgent need for approaches that provide early identification of drug-resistance viral variants in patients.

This patent is subject to a terminal disclaimer.

Detection of drug-resistant human immunodeficiency virus