A digitally controlled switched-mode voltage converter having conversion circuit (CMS) including a switching device (SW) for the purpose of converting an input voltage (U.sub.i) into an output voltage (U.sub.o); and a control device (CM) for controlling a duty cycle of the switching device (SM) in steps having discrete values (D.sub.c1,D.sub.c2). The control device (CM) include a change-over device (SO) for continually switching the duty cycle between at least two discrete values (D.sub.c1,D.sub.c2) in such a manner that the average value of the duty cycle corresponds to a target duty cycle (T.sub.dc).

The invention relates to a digitally controlled switched-mode voltage convertor comprising conversion means including switching means for the purpose of converting an input voltage into an output voltage; and control means for controlling a duty cycle of the switching means in steps having discrete values.
Such a voltage convertor is known from German Patent Specification 2746578. In said converter the desired output voltage is obtained by the stepwise control of the duty cycle of a switch (i.e. the time during which the switch is closed divided by the sum of the time during which the switch is closed and the time during which the switch is open). For example, if the output voltage is to be raised the duty cycle is increased in steps.
A disadvantage of the known convertor is that the accuracy of the output voltage, i.e. the voltage resolution, is limited in that the voltage resolution is correlated with the time resolution of the voltage convertor, which time resolution is defined by the duty cycle, which can be adapted in discrete steps.
In the known voltage convertor the voltage resolution can be improved by reducing the step size of the discrete steps by a given factor. For a similar voltage range of the output voltage the number of discrete steps should then be increased by the same factor. This means that if the duty cycle of the switch is minimum, which occurs at the smallest possible value of the output voltage, the value of the duty cycle has been reduced by the above-mentioned factor. However, the maximum value of the duty cycle, which occurs at the largest possible value of the output voltage, does not change. It follows that the ratio between the maximum value of the duty cycle and the minimum value of the duty cycle has (potentially) increased by the above-mentioned factor. The shortest time during which the switch is closed (during the minimum value of the duty cycle) dictates the maximum period of a system clock that is required. This maximum period corresponds to a minimum system clock frequency of the system clock. It will be evident that in an attempt to improve the voltage resolution, by reducing the step size of the discrete steps (or by increasing the time resolution) by a given factor, the minimum system clock frequency increases by this given factor.
The above solution is disadvantageous because, in order to enable the voltage resolution to be made sufficiently high, the minimum required system clock frequency could be so high that the electronic circuitry required for this purpose is highly intricate, dissipates much power, or is even impracticable. A solution for this is to increase the switching period of the switch, i.e. the sum of the time that the switch is closed and the time that the switch is open, without the duty cycle being changed. In that case the minimum system clock frequency can be reduced proportionally. Phrased differently, the minimum system clock frequency is directly proportional to the minimum switching frequency (the reciprocal of the switching period of the switch).
However, the above-mentioned solution has another disadvantage. Switched-mode voltage convertors generally include a coil. The energy losses of the voltage convertor, for a given duty cycle, are then inversely proportional to the value of the self-inductance of the coil, and inversely proportional to the switching frequency. Since the self-inductance cannot be arbitrarily large in view of the coil dimensions, the efficiency of the voltage convertor will be lower in the case of a reduced switching frequency.
Summarizing, it can be stated that increasing the voltage resolution of the voltage convertor by increasing the time resolution is subject to limits imposed by a minimum system clock frequency, on the one hand, and a maximum system clock frequency, on the other hand.
Furthermore, it is to be noted that the capacitance of a smoothing capacitor, which is generally present, should be higher as the switching frequency decreases. This results in an undesirable increase in the size of the smoothing capacitor.

Digitally controlled switched-mode voltage converter


An interface system is presented, which prevents operational interference between a vehicle power door and a ramp of an access system by interrupting power to the motors and actuators responsible for operating the door. The interface system includes a relay system that does not interrupt, read, signal, or otherwise interfere with the communication lines between a body control unit, door control unit, or remote control transmitter or receiver. Thus, the interface system functions without the need to receive and transmit signals on the vehicle's communication bus. The interface system enables the ramp controller of the access system to be a separate module, which controls the ramp and kneel functions, because the only input the ramp controller provides to the power door system is to a ground signal that mimics that of a switch included in the vehicle.

Access systems, such as motorized lifts, have been used to transport people and cargo. These access systems include platforms, ramps, moving seats, movable steps, and the like, which may be attached to stationary structures, such as buildings and loading docks, or mobile structures such as vehicles. Access systems have been used to provide disabled individuals access to structures that traditionally were accessible only via steps or stairs, or required an individual to step over or across an obstacle. For example, motorized lifts have been used to allow disabled individuals to enter and exit vehicles. In another example, motorized lifts have been used to load and/or unload stretchers from vehicles, such as ambulances. Motorized lifts have also been used on loading docks and trucks to allow cargo to be loaded, unloaded or otherwise moved.
When an access system is installed in a vehicle, it is generally integrated with the power sliding door system of the vehicle. The power sliding door system opens or closes the door when it receives a request to do so (a "door operation request"). The power sliding door system further includes a body control unit, door control unit, receiver, door switch and data bus. The body control unit, door control unit, receiver and door switch are all in communication with the vehicle's data bus, which enables body control unit, door control unit, receiver and door switch to communicate with each other and to receive a signal from a user indicating that the user wants to open or close the door (a "door operation request"). Generally, the user may communicate a door operation request to the power system door system by pulling on a door handle of the vehicle or pushing a button on a keyless entry device. If the door operation request is produced by a remote device, the power sliding door system receives the door operation request via the receiver. If the door operation request is produced by movement of the door handle, the door operation request causes the door switch to close, which communicates the door operation request to the power sliding door system.
When a door operation request received by the power sliding door system, it is initially received by the body control unit. The body control unit evaluates whether it is an appropriate time to operate the door. For example, the body control unit may receive signals via the data bus indicating the status of the transmission position, speed and door lock position of the vehicle. If the body control unit determines that the status of the vehicle are acceptable, the body control unit communicates a command to operate the door (a "door operation command") to the motors and switches that unlatch the door and either open or close the door.
Access systems are installed in vehicles with a power sliding door system as described above, so that the operation of the ramp by the access system and operation of the door by the power sliding door system do not interfere with each other. To prevent such interference, the access system may be installed so that it receives the door operation commands from the body control unit. The access system will only communicate the door operation command when it determines that the ramp is fully stowed. This method requires the access system to be in communication with the data bus of the power sliding door system, either directly or through a gateway. However, vehicle manufacturers are becoming less willing to allow access systems to communicate with the data bus and thus, unwilling to allow access systems to be installed and operate in the manner described above.

Switch-based door and ramp interface system


This disclosure relates to winking to capture image data using an image capture device that is associated with a head-mountable device (HMD). An illustrative method includes detecting a wink gesture at an HMD. The method also includes causing an image capture device to capture image data, in response to detecting the wink gesture at the HMD.

Computing devices such as personal computers, laptop computers, tablet computers, cellular phones, and countless types of Internet-capable devices are increasingly prevalent in numerous aspects of modern life. Over time, the manner in which these devices are providing information to users is becoming more intelligent, more efficient, more intuitive, and less obtrusive.
The trend toward miniaturization of computing hardware, peripherals, sensors, detectors, and image and audio processors, among other technologies, has helped open up a field sometimes referred to as "wearable computing." In the area of image and visual processing and production, it has become possible to consider wearable displays that place a very small image display element close enough to one or both of the wearer's eyes such that the displayed image fills or nearly fills the field of view, and appears as a normal sized image, such as might be displayed on a traditional image display device. The relevant technology may be referred to as "near-eye displays."
Near-eye displays are fundamental components of wearable displays, also sometimes called "head-mountable displays". A head-mountable display places a graphic display close to one or both of the wearer's eyes. To generate the images on the display, a computer processing system can be used.
Emerging and anticipated uses of wearable displays include applications in which users interact in real time with an augmented or virtual reality. These applications can be mission-critical or safety-critical in some fields, such as public safety or aviation.


An improved drug delivery composition and method of use is disclosed. The composition comprises one or more biodegradable block copolymer drug carriers; and a reconstitution enhancing and enabling agent comprising polyethylene glycol (PEG), a PEG derivative or a mixture of PEG and a PEG derivative. The composition can be administered as is or after being be dissolved or rapidly reconstituted in an aqueous vehicle to afford a homogeneous solution or uniform colloidal systems.

Biodegradable polymers have been used as surgical sutures, wound dressings, and as drug delivery systems. Among them, polylactide (PLA), polyglycolide (PGA) and their copolymers (PLGA) have attracted the most attention. One example of a biodegradable polymeric drug delivery system is a system wherein a drug is contained in a biodegradable polymer matrix that is surgically implanted, which is a big disadvantage. In the form of injectable drug delivery systems, polymeric microspheres and nanospheres are known in the art. Commercially available drug delivery formulations based on PLGA microspheres include Lupron Depot® and Nutropin Depot®. Microsphere and nanosphere systems have disadvantages in that they require special and complex preparation methods. Unfortunately, manufacturing microsphere and nanosphere dosage forms requires use of toxic or dangerous solvents (e.g., methylene chloride, ethyl acetate) and elaborate procedures (e.g., double emulsions, or cryogenic spraying techniques). The batch size is usually small and the cost is high. In addition, since PLGA biodegradable polymers used can only be dissolved in organic solvents their preparation requires the use of such solvents which are foreign and harmful to the human body, and cannot be completely removed during manufacture by any known method. Furthermore, some drugs such as peptides and proteins may lose their pharmacological activity after contact with organic solvents.
An improvement to the aforementioned drug delivery systems is an in situ formed depot based on PLGA as disclosed in U.S. Pat. No. 5,599,552. In that system, PLGA is dissolved in water-soluble organic solvent(s), such as N-methyl-2-pyrrolidone, and the drug is either suspended or dissolved in this polymeric solution. The solution can be injected subcutaneously to form an in situ depot to trap the drug in the polymer that precipitates as the organic solvent diffuses away. However, the drawback is the requirement for an organic solvent that is used to dissolve the biodegradable PLGA polymer. Organic solvents, such as N-methyl-2-pyrrolidone, are foreign to the human body and can cause unwanted side effects both acutely and chronically.
U.S. Pat. No. 5,543,158 discloses nanoparticles or microparticles formed from a water-insoluble block copolymer consisting essentially of poly(alkylene glycol) and poly(lactic acid). The molecular weight of the block copolymer is high and the copolymer is insoluble in water. In the nanoparticle or microparticle, the biodegradable moieties of the copolymer are in the core of the nanoparticle or microparticle and the poly(alkylene glycol) moieties are on the surface of the nanoparticle or microparticle in an amount effective enough to decrease uptake of the nanoparticle or microparticle by the reticuloendothelial system. Nanoparticles are prepared by dissolving the block copolymer and drug in an organic solvent, forming an o/w emulsion by sonication or stirring, and collecting the nanoparticles containing the drug following precipitation.
Currently there are few synthetic or natural polymeric materials that can be used for the controlled delivery of drugs, including peptide and protein drugs, because of strict regulatory compliance requirements such as biocompatibility, low toxicity, having a clearly defined degradation pathway, and safety of the polymers and degradation products. The most widely investigated and advanced biodegradable polymers in regard to available toxicological and clinical data are the aliphatic poly(α-hydroxy acids), such as poly(D-, L-, or D, L-lactic acid) (PLA), poly(glycolic acid) (PGA) and their copolymers (PLGA). These polymers are commercially available and are presently used as bioresorbable sutures and in biodegradable microsphere drug delivery systems. FDA-approved microsphere systems for controlled release of leuprolide acetate (Lupron Depot™) and human growth hormone (Nutropin Depot™) are based on PLGA copolymers. Based on this history of use, PLGA copolymers have been the materials of choice in the initial design of parenteral controlled release drug delivery systems using a biodegradable carrier.
Even though there has been some limited success, biodegradable block copolymers that are based on biodegradable polyester or poly(ortho ester) and polyethylene glycol (PEG) blocks, when used as drug carriers, present problems that are associated with their physicochemical properties and attendant methods of fabrication. For example, biodegradable block copolymers are, by design, not stable in aqueous environments although shelf-lives of several years can be achieved when they are stored frozen. However, elimination of cold storage requirements would be advantageous in most instances. It is also desirable to gain further advantages related to rapid dissolution of neat block copolymers into aqueous vehicles at normal or ambient room temperature conditions. Rapid dissolution of the block copolymers permits reconstitution at time-of-use to occur, which in turn permits room temperature storage of neat block copolymers. Known water soluble block copolymers are slow to dissolve in water, often requiring several hours for complete dissolution to occur. Compositions that show accelerated dissolution kinetics are desired.
Some drugs, such as proteins, are stable in aqueous solutions for only short periods. To compensate for this short-term stability, these drugs are commonly formulated as dry cakes and powders that can be stored under water-free conditions for much longer periods. Immediately prior to administration the dry cake or powder is reconstituted with an aqueous vehicle. Thus the situation is frequently encountered where it is desirable to have both the drug and the block copolymer drug delivery system formulated in reconstitutable forms. To be facile, it is critical that reconstitution, i.e., dissolution of the block copolymers and drug be completed in a short period.
U.S. Pat. No. 5,384,333 discloses an injectable drug delivery composition in which a pharmacologically active substance is contained in a copolymer comprising a hydrophilic part and a hydrophobic part. However, the composition has to be heated to a relatively high temperature such as 38° C. to 52° C., immediately before use and it is difficult to uniformly distribute the drug in the polymeric composition. U.S. Pat. No. 5,612,052 discloses a block copolymer composition that when contacted with water forms a hydrogel. However, the drug incorporated in this composition is rapidly released. U.S. Pat. No. 5,599,552 discloses a composition wherein a water-insoluble biodegradable thermoplastic polymer is dissolved in a water-miscible organic solvent, and the resulting composition can be implanted where it then undergoes a phase transition when in contact with water or body fluids. However, the drawback is that it is difficult to use because a mono-molecular organic solvent is used to dissolve the biodegradable thermoplastic polymer. Most mono-organic solvents, such as N-methy-2-pyrrolidone, ethyl lactate, dimethylsulfoxide, etc., cause side effects such as cell dehydration and tissue necrosis, etc. and they may also cause severe pain at the application sites.
U.S. Pat. No. 5,607,686 discloses a liquid polymeric composition prepared by mixing a hydrophilic liquid polymer, instead of a mono-molecular organic solvent, with a water-insoluble hydrophobic polymer. When contacted with water the composition undergoes a phase transition and forms an implant and thus it does not cause a the rapid volume reduction and it has no special side effects due to the good cyto-compatibility of the low molecular weight polyethylene oxide. However, the water-insoluble hydrophobic polymers used are not biodegradable. In addition, the preparation of the composition requires heating to about 80° C. in order to achieve uniform mixing of the water-insoluble hydrophobic polymer and the hydrophilic liquid polymer. Therefore, this system may be suitable to use for adherence prevention and wound protection without any physiologically active substance, but it is not suitable for delivery of physiologically active substances, particularly peptide or protein medicines because peptide and protein medicines lose their activities at high temperatures. Furthermore, protein medicines are water soluble, thus it is very difficult to uniformly incorporate them into the composition. In addition, it is not disclosed in this patent how the drugs or physiologically active substances can be uniformly incorporated in the polymeric composition. Particularly, although polylactide, polyglycolide and their copolymers can be mixed with polyethylene glycol at high temperatures of 80° C. in order to obtain a uniform composition, the composition undergoes phase separation when it stands for a long period of time due the lowered affinity of the polylactide, the polyglycolide or their copolymers with polyethylene glycol. Therefore, it is very difficult to maintain a uniform composition.
Sterilization steps are necessary in the preparation of implant formulations. Existing sterilization methods are unsuitable for sustained drug delivery formulations due to properties of the implant compositions or because the methods are uneconomical or too complicated. For example, it is almost impossible to prepare a uniform solution by mixing a drug, a water-insoluble biodegradable polymer and a hydrophilic polymer. Therefore, the composition cannot be sterilized by simple methods such as membrane filtration. Furthermore, although the formulation may be prepared under sterilize conditions, such methods are very expensive to the extent that the practicability of the preparation may be lowered.
Therefore, there is a need for a biodegradable drug delivery composition that is a flowable liquid or can be rapidly reconstituted in an aqueous vehicle to afford a homogeneous true solution or uniform colloidal system in order to be easily prepared and administered to provide improved drug delivery. Accordingly, the present invention represents improved drug delivery compositions that minimize or are free of the problems mentioned above.

Biodegradable block copolymeric compositions for drug delivery


A method programs a memory cell by controlling a reverse bias voltage across the PN junction between a source electrode of a MOSFET in the memory cell and the substrate, and pulling back the pinch-off point of the inversion region toward the source electrode, thereby increasing the programming efficiency of the memory cell. The method applies the main positive supply voltage Vcc to, the drain electrode of the memory cell from the chip main voltage supply, rather than the conventional method of using a higher voltage than Vcc. To optimize the programming condition, the source voltage and the substrate voltage are adjusted to achieve the maximum threshold voltage shifts under the same applied gate voltage pulse condition (i.e. using the gate pulse with the same voltage amplitude and duration regardless of the source voltage and the substrate voltage). The substrate voltage to the drain voltage can not exceed the avalanche multiplication junction breakdown for a small programming current during the bias voltage adjustment.

As shown in FIG. 1, metal oxide semiconductor field effect transistor 10 (MOSFET) includes a source 13 and a drain 14 (connected respectively to source electrode 13a and drain electrode 14a) each with an impurity type opposite to the impurity type of the substrate 15. The source 13 and drain 14 are separated by a channel region in the substrate 15 underlying a control gate 11 formed over a dielectric layer 12 on top of the silicon substrate 15. When the voltage applied to the gate electrode 11a electrically connected to control gate 11 exceeds the threshold voltage of the MOSFET 10, the channel region in the substrate 15 between the source 13 and the drain 14 and just below the dielectric 12 under the control gate 11 of the MOSFET device 10 is inverted to the same conductivity type as the source 13 and drain 14 to make electrical connection between source 13 and drain 14. A non-volatile memory (NVM) cell stores information by placing charges in the storing material 12b between the control gate 11 and the channel region of the MOSFET 10. In FIG. 1, charge is shown as being stored in region 12b of dielectric 12 but it should be understood that the charge could be stored on a conductive floating gate in region 12b or in nanocrystals in the dielectric 12 such as the region 12c above 12b or the region 12a below 12b. Thus the storing material can be a conducting material such as highly doped poly-silicon, charge trapping dielectric such as a nitride film, or nano crystals. By placing charges in the storing material 12b in an NVM cell, the threshold voltage of the MOSFET device 10 can be altered. Various values of information can thus be stored in an NVM cell by placing various amounts of charge in the storing material 12b to alter the threshold voltage level of the NVM cell. The value of the information stored corresponds to the amount of charge stored which in turn can be determined by determining the threshold voltage of the MOSFET device 10 in the cell. The stored charges in an NVM cell are not volatile even when the power for the NVM device is turned off. The information stored in an NVM cell can be retrieved by determining and reading out the threshold voltage of the MOSFET 10 in the NVM cell.
To place different amounts of charge in the storing material 12b of an NVM cell is called "programming" or "writing". In contrast, to erase an NVM cell, the stored charges must be removed from the storing material 12b. The method used to program an NVM cell has been based on three mechanisms: 1. Hot Carrier Injection (HCI); 2. Fowler-Nordheim (FN) tunneling; 3. Band-to-band tunneling (See. IEEE Std 1005-1998 and IEEE Std 641-1987). HCI and FN tunneling are the two most commonly used programming mechanisms for NVM devices. HCI is the fastest programming method to obtain the desired threshold voltage shift associated with MOSFET 10 in an NVM cell but uses large programming current, while FN tunneling uses little programming current but requires a longer programming time to achieve the desired threshold voltage shift.
Conventional HCI programming applies a relatively high voltage (greater than Vcc, the regular supply voltage applied to the memory during normal operation) to the drain electrode 14a and the control gate electrode 11a of the MOSFET 10 in an NVM cell, while the substrate 15 or source electrode 13a are connected to ground. In such a way, an inverted region 17 (i.e. a region with the same conductivity type as the source 13) is created in the channel region adjacent to the source 13 extending toward, but not reaching the drain 14. A depletion region 16 as shown in FIG. 1 is formed beneath the source 13, the inverted region 17, in the channel region directly beneath the gate electrode 11 but beyond the point 19 where the inverted region 17 ends (called the "pinch-off point") and beneath the drain 14. A high lateral electric field is created in the depletion region 16 between the pinch-off point 19 and the drain electrode 14. As shown schematically in FIG. 1, the channel inversion layer 17 is wider near the source 13 and narrows as it approaches the pinch-off point 19. As the charge carriers current Is at the source side passes through the pinch-off point 19, the charges, now forming current Id at the drain side are strongly accelerated toward the drain 14 in the high field of the drain-depletion region (i.e. the portion of depletion region 16 between pinch-off point 19 and drain 14). As a result, the charge carriers are scattered in a direction such as to reach the Si/SiO2 interface (i.e. the interface between the silicon substrate 15 and the SiO2 (dielectric 12). The shape of the SiO2 (dielectric 12) energy barrier varies along with the channel length (i.e. the length of inversion region 17) due to the substrate 15 surface potential variation induced by the applied constant control gate 11 voltage and constant drain 14 voltage bias. Consequently, near the source electrode 13, the oxide field is very strongly biased toward the direction of gate 11 but with almost no available hot carriers for injection into the storing material 12b. While abundant hot carriers are generated near the depletion region between pinch-off point 19 and drain electrode 14, there is only a very small electric field from oxide 12 to substrate 15 (called the "oxide field") near the pinch-off point 19 in the depletion-drain region (i.e. in the region between the pinch-off point 19 and drain 14) to collect the hot carriers, which form a weak substrate current Isub. Less than one per million of hot carriers is collected toward the oxide field and thus flows into storage material 12b. With injection of carriers from the source 13, a large number of secondary carriers generated in the depletion-drain region flow into the drain electrode 14 and fractions of them flow into the substrate 15. The programming efficiency is thus very low. The typical programming current flowing through the drain electrode 14 of MOSFET 10 in an NVM cell is around hundreds of microampere per cell and only a small fraction of the current flows to the charge storage material 12b.
In the conventional wisdom, the applied drain voltage cannot be lower than 3.1 V, which is the oxide barrier voltage for electrons to move inside the oxide field, for programming the MOSFET 10 in an NVM device using the HCI scheme (See Kinam Kim and Gitae Jeong, ISSCC Tech. Dig, pp. 576-577, 2005). This conventional belief imposes the condition that the drain 14 voltage must be higher than 3.2 volts and the drain electrode 14a must be supplied with a higher voltage supply usually between 3.5 volts to 6 volts. While MOSFET devices are scaled down to a smaller geometry, the main voltage supply, Vcc is scaled down accordingly. For example, the main voltage supply is as low as 1 volt for the technology nodes in nanometer scale generations. Thus, in the conventional HCI programming scheme, charge pumping circuitry is required to supply voltages higher than Vcc to the drain electrode 14a of NVM cells. It becomes very challenging for charge pump circuit design to support a high current load while maintaining a constant higher drain 14 voltage bias during programming MOSFET 10 in an NVM cell. For parallel programming an array of NVM cells, the programming uniformity can also be compromised from the high voltage supply dropout due to high current load. Due to this programming voltage bias incompatibility with the main voltage supply Vcc (ie, the programming voltage must be higher than Vcc), a complicated high voltage decoder including high voltage level shifters in the bitlines of an NVM array is also required for selective bitline switching.

Method and structures for highly efficient hot carrier injection programming for non-volatile memories


An articulated arm for awnings is disclosed. The articulated arm comprises an arm and a forearm, joined together by respective articulation configurations located at adjacent ends of the same, which enables them to move between open and closed positions. There is a flexible tie bar inside the arm, with a second end anchored to the articulation configuration of end of the forearm and linked by a first end to an elastic traction element anchored to a fixed point on the arm and an elastic compression element located between a stop on the flexible tie bar and a support of the end of the arm in order to produce tension in the tie bar on moving from the open position to closed, generating torque tending towards the open position.

The articulated arm configuration for an awning that consists of an arm and forearm comprising respective tubular arms with ends terminating in plug-in parts that define articulation configurations is a classic design. The arm and forearm are joined together by means of an articulation formed by two of the said adjacent articulation configurations. Within the profile that makes up the body of the arm is the spring under traction that is joined at one end to a fixed point on the tubular profile and by the other end to a flexible tie bar, which is fixed at the other end to a core of the forearm articulation configuration. A portion of the mentioned flexible tie bar is supported on a surface of the said core relatively removed from the rotation axis of the articulation in order to create, in virtue of the tension produced by the spring under traction, a rotational torque that tends to maintain the arm and forearm in a open position.
International patent application WO 98/01638 of the actual applicant describes an articulation for supporting awnings of the type described above, which contributes a series of improvements for the articulation, and in which the mentioned flexible tie bar comprises a flat belt interiorly fitted with metal reinforcement filaments. This belt includes terminals at its two ends for joining the belt to the traction spring and the core respectively. The two ends of the belt include cast terminals for joining the belt to the elastic traction element and to the core. The said terminals are connected to the ends of the cited metal reinforcement filaments at the ends of the belts.
One inconvenience of this type of awning arm is that the increase in rotational torque provided by the lengthening of the elastic traction element as the arm and forearm move from an open position to a closed one turns out to be insufficient with respect to the increase in resisting torque generated by the tension in the awning at the end of the forearm, taking into account that the arm and forearm adopt ever-increasingly inclined positions with respect to the line of application of the tension in the awning as they close. When the awning canvas is completely wound onto the roll-up bar and the arm is fully folded, the elastic energy accumulated in the elastic traction element may be insufficient to push the loading bar towards an open position as the canvas is unwound.
There is, therefore, a need for an articulated awning arm with an improved elastic effect that provides an initial tension when the arm is sufficiently open to maintain the awning canvas with an adequate level of tension and that possesses sufficient accumulated elastic energy when the arm is closed to push the awning canvas to an open position as the canvas is unwound.

Articulated arm for awnings, with improved elastic effect


A word line driver circuit allows for dynamic selection of different word line voltages for selection and deselection of memory cells included in a resistive memory array in a manner that reduces circuit complexity, device count, and leakage currents.

Resistive memory devices store information by varying the resistance across the memory device such that a read current through a memory cell in the memory device will result in a voltage drop having a magnitude that is based on the information stored in the memory cell. For example, in certain magnetic memory devices, the voltage drop across a magnetic tunnel junction (MTJ) can be varied based on the relative magnetic states of the magnetoresistive layers within the memory cell. In such memory devices, there is typically a portion of the memory cell that has a fixed magnetic state and another portion that has a free magnetic state that is controlled to be either parallel or antiparallel to the fixed magnetic state. Because the resistance through the memory cell changes based on whether the free portion is parallel or antiparallel to the fixed portion, information can be stored by setting the orientation of the free portion. The information is later retrieved by sensing the orientation of the free portion. Such magnetic memory devices are well known in the art.
Writing magnetic memory cells can be accomplished by sending a spin-polarized write current through the memory device where the angular momentum carried by the spin-polarized current can change the magnetic state of the free portion. One of ordinary skill in the art understands that such a current can either be directly driven through the memory cell or can be the result of applying one or more voltages where the applied voltages result in the desired current. Depending on the direction of the current through the memory cell, the resulting magnetization of the free portion will either be parallel or antiparallel to the fixed portion. If the parallel orientation represents a logic "0", the antiparallel orientation may represent a logic "1", or vice versa. Thus, the direction of write current flow through the memory cell determines whether the memory cell is written to a first state or a second state. Such memory devices are often referred to as spin torque transfer memory devices. In such memories, the magnitude of the write current is typically greater than the magnitude of a read current used to sense the information stored in the memory cells.
As with other integrated circuits, it is desirable to minimize the number of devices needed to implement the desired functionality. Fewer devices can provided benefits such as reduced area, less cost, and reduced failure rates. As discussed above, the various reading and writing operations in memory devices can require different currents to flow through the memory cells. Generating and controlling those different currents in an optimized manner can help to improve read/write timing as well as reduce power consumption, leakage currents, and circuit complexity. Therefore, it is desirable to provide circuits and methods to facilitate reading and writing to such memory devices in accordance with these objectives.

This patent is subject to a terminal disclaimer.


The present invention relates to an air quality monitoring and controlling system and method for enclosed spaces, which provides an innovative closed loop (i.e., inline real time feedback) air management process, utilizing learning and prediction capabilities to provide with effective air purification and reliable alerting when required.

The monitoring of air quality in enclosed spaces requires the use of multiple different sensors, e.g., smoke detectors, LPG (liquid petroleum gas) and CO (carbon monoxide) sensors, while each type of sensor has specific characteristics, and therefore, its particular work conditions and feasible applications. Similarly, multiple different air filters may be required for the reduction of unwanted airborne substances to a desirable level, wherein each type of filter has its specific characteristics, for example, coarse filters for large sized particles vs. fine filters.
The operation of existing air quality monitoring and control systems is generally focused on monitoring and controlling of particulate sizes, and do not provide highly reliable monitoring and controlling of air pollution and hazardous substances, resulting with false alarms, and late detection.
The present invention utilizes the progress in the IOT and AI fields for an advanced prediction capability, which provides a solution to the abovementioned disadvantages of the prior art.

Air quality management device, an air quality control system, and a method for controlling air quality


Disclosed is a carbon-fiber chopped strand, and a manufacturing method of the same. The carbon-fiber chopped strand is composed of single filaments composed of 30,000-120,000 carbon fibers, and a sizing agent content 1-10% by weight that bundles the single filaments; the ratio of maximum diameter (Dmax) in the cross section and minimum diameter (Dmin) is 1.0-1.8, a length along a fiber direction is 3-10 mm, and a repose angle of 10-30°.

Short-carbon-fiber-reinforced thermoplastic resin (hereinafter referred to as "CFRTP") produced using a thermoplastic resin as a matrix resin, has drawn attention as a high-performance engineering material, and the demand therefor is increasing rapidly. This CFRTP can be produced by injection molding and accordingly is high in productivity. Moreover, the CFRTP, as compared with conventional non-reinforced thermoplastic resins or short-glass-fiber-reinforced thermoplastic resins, is superior in mechanical properties, sliding property, electrical properties, dimensional stability, etc.
As the method for producing the CFRTP, there are ordinarily the following methods.    (1) First, there is fed, into an extruder, a carbon-fiber filament bundle cut into 3 to 10 mm and bundled with a sizing agent (a so-called carbon-fiber chopped strand) or a so-called milled carbon fiber ground into 1 mm or shorter, together with pellets or a powder of thermoplastic resin; and they are melt-kneaded therein to obtain pellets. Then, the pellets are made into a CFRTP using an injection molding machine or an extrusion molding machine.    (2) A carbon-fiber chopped strand is fed into an extrusion molding machine together with pellets or a powder of thermoplastic resin to directly produce a CFRTP.
Meanwhile, as the method for feeding a carbon-fiber chopped strand and a thermoplastic resin into an extruder to produce pellets, the following methods are employed mainly.    (1) A method of dry-blending a carbon-fiber chopped strand and a thermoplastic resin and feeding the resulting blend into an extruder (a dry-blending method).    (2) A method of feeding a thermoplastic resin into the rear end side (in extrusion direction) of extruder and feeding a carbon-fiber chopped strand to the intermediate portion (in extrusion direction) of extruder wherein the fed thermoplastic resin is in a molten state (a side-feeding method).
As well known, the properties of CFRTP are related to the fiber length of the carbon fiber of CFRTP. When there is used a milled fiber of extremely short fiber length, the fiber length in the molded CFRTP is extremely short; accordingly, the properties of this CFRTP are inferior to those of CFRTP using a carbon-fiber chopped strand.
In order to keep long the fiber length of CFRTP, there is a case that a CFRTP is produced using a long fiber pellet having a fiber length same as the cut length of carbon-fiber chopped strand. In this case, the fiber direction in the CFRTP obtained is difficult to control. Therefore, this method of CFRTP production using a long fiber pellet is disadvantageous for production of an inexpensive CFRTP which needs to be mass-produced. For the above reasons, carbon-fiber chopped strand is generally used in production of CFRTP.
In production of CFRTP, when the carbon-fiber chopped strand used is low in flowability, there is a problem that stable feeding of carbon-fiber chopped strand into extruder is difficult.
In the dry-blending, when the carbon-fiber chopped strand used is low in flowability, there is a problem that the carbon-fiber chopped strand is difficult to flow down in the hopper of extruder or injection molding machine. As a result, the feeding of the carbon-fiber chopped strand in a given amount from the meter provided at the bottom of hopper, to the extrusion screw of extruder becomes unstable. For the above reason, it is difficult to obtain a CFRTP of uniform composition stably and, moreover, the production efficiency is low.
Meanwhile, in the side-feeding method as well, when the carbon-fiber chopped strand used is low in flowability, the carbon-fiber chopped strand is not fed stably into the extrusion screw of extruder and, in an extreme case, the feeding itself of the carbon-fiber chopped strand may be impossible.
For these reasons, a carbon-fiber chopped strand used industrially in a large amount is required to have high flowability. In order to respond to this requirement, it is conducted to add a sizing agent of high bundling ability to a carbon-fiber chopped strand or add a sizing agent in a large amount. It is also conducted to add another sizing agent to a carbon-fiber chopped strand obtained by cutting a strand, to mold the carbon-fiber chopped strand into a rice grain shape.
However, in producing a CFRTP by mixing the above-mentioned chopped strand containing a large amount of a sizing agent, with a heat-resistant thermoplastic resin of high processing temperature, a gas is generated by the thermal decomposition of the sizing agent. This gas allows the obtained CFRTP to have poor appearance or low weld strength (see, for example, Patent Literatures 1 and 2). Further, the thermal decomposition of the sizing agent tends to cause reduction in properties of CFRTP.
Further, in melt-kneading a chopped strand with a thermoplastic resin in an extruder, there is a case that the sizing agent added in a large amount to the carbon fiber of chopped strand reduces the dispersibility of the carbon fiber. In this case, the dispersibility of carbon fiber in the pellet obtained is insufficient. When a CFRTP is produced using this pellet, there are present, in the CFRTP produced, fiber bundles not dispersed sufficiently. The fiber bundles become a center of stress concentration, reducing the mechanical properties (particularly, tensile strength) of the CFRTP.
Meanwhile, in order to produce a chopped strand in a large amount, it is effective to increase the number of single filaments constituting the chopped strand. Chopped strands composed of 30,000 or more single filaments are known. Such a chopped strand has a flat shape. The flat shape makes easy the single-filament-state dispersion of carbon fiber in CFRTP, whereby the assembling of carbon fibers in bundle shape can be avoided.
However, the chopped strand of flat shape has a large surface area, resulting in a large contact area between chopped strands. Consequently, the chopped strand has low flowability and, in feeding the chopped strand into an extruder, there arises poor feeding into meter or extruder.
Further, the above poor feeding makes long the residence time of chopped strand in extruder. In this case, the chopped strand undergoes larger shear by the screw of extruder and the breakage of carbon fiber takes place. As a result, the fiber length becomes short, resulting in reduction in mechanical properties of the CFRTP obtained.
As described above, it has been difficult to allow a carbon-fiber chopped strand to have high flowability without reducing the dispersibility of carbon fiber and the properties of the CFRTP obtained and thereby to feed the chopped strand in a large amount in a stable state from the hopper of extruder to the extrusion screw of extruder.
Patent Literature 1: JP-A-2003-165849
Patent Literature 2: JP-A-2004-149725

Carbon-fiber chopped strand and manufacturing method of the same


A communication system provides one or more of congestion information and subscriber information to a broadcast applications server when the server receives a request to start a broadcast-multicast service in a coverage area. By providing the one or more of congestion information and subscriber information to the server, the server is able to make an informed, intelligent decision concerning blocking, unblocking, downgrading, or upgrading a broadcast-multicast flow of multiple broadcast-multicast flows requested for delivery to, or currently delivered to, the coverage area via a serving base station, and/or whether to add a new broadcast-multicast flow to the broadcast-multicast flows delivered to the coverage area.

The Third Generation Partnership Project Two (3GPP2) standard provides a compatibility standard for cellular mobile telecommunications systems. The 3GPP2 standard ensures that a mobile station (MS), or access terminal (AT), (hereinafter collectively referred to as an MS) operating in a cdma2000 (Code Division Multiple Access 2000) communication system (such as a 1× system or a DO system) can obtain communication services when operating in a system manufactured according to the standards. To ensure compatibility, radio system parameters and data transfer procedures are specified by the standards, including protocols governing digital control messages and bearer traffic that are exchanged over an air interface.
The 3GPP2 standards provide, in the X.P0022, A.S00019, and S.R0083 specifications, for delivery of a Broadcast-Multicast Service (BCMCS) by a cdma2000 communication system to MSs serviced by the system and subscribed to the Service. For example, a BCMCS may deliver a broadcast-multicast flow of audio, video, and/or data associated with a multimedia program such as a Cable News Network (CNN) newscast or an Home Box Office (HBO) show. When a MS activates in a communication system that provides a BCMCS, the MS may request access to one or more broadcast-multicast flows associated with the BCMCS by indicating to the communication system, and in particular to a BCMCS Controller, a willingness to receive multicast data associated with the BCMCS flow. By registering for the BCMCS, and for particular broadcast-multicast flows, the MS joins a broadcast/multicast group associated with those flows.
In response to receiving an access request from a MS for a broadcast-multicast flow, the BCMCS Controller conveys to the MS multiple identifiers (BCMCS_FLOW_ID and BAK_ID) associated with that flow, that is, with the particular program, such as CNN or HBO, subscribed to by the MS and an encryption key (EncrBAK) used to encrypt the audio, video, and/or data associated with that flow. When the BCMCS Controller receives BCMCS data associated with the flow, the BCMCS Controller may cause the data to be encrypted using the EncrBAK key and to be broadcast via a Base Station (BS) or an Access Network (AN) (hereinafter collectively referred to as a BS) servicing the MS. Each subscribed MS may then decrypt the broadcast audio, video, and/or data using the provided key and display the audio, video, and/or data to the user of the MS. When an MS subscribes to multiple BCMCS flows, the MS is provided a Flow ID and an encryption key associated with each such flow. The user of the MS may then select, at any time, which broadcast-multicast flow of the multiple broadcast-multicast flows to decrypt and to listen to or watch.
Currently, the 3GPP2 standards do not regulate a quantity or quality of broadcast-multicast flows conveyed by a BCMCS Controller to a BS and subscribed to by MSs serviced by the BS. That is, in providing broadcast-multicast flows associated with Broadcast-Multicast Services to a BS, the BCMCS Controller may have to provide all flows subscribed to by all MSs serviced by the BS regardless of the available bandwidth or channel conditions at the BS. This unregulated conveyance of flows can produce congestion in the BS due to a lack of available bandwidth for a broadcast of all received flows. As a result, the BS may end up arbitrarily blocking some of the received flows and/or arbitrarily reducing a Quality of Service (QoS) of one or more concurrently received flows. In addition, the BS is unaware of subscription information related to each MS subscribing to one or more such flows and serviced by the BS. For example, when an MS subscribes to a BCMCS, the MS may further specify a particular QoS for the Service, for example, to a Gold, Silver, or Bronze plan, or may understand that a particular BCMCS will be provided at a predetermined QoS. When the BS arbitrarily blocks received flows or arbitrarily reduces QoS, the BS may block broadcast-multicast flows subscribed to by a large number of subscribers while broadcasting broadcast-multicast flows with a low number of subscribers or may reduce QoS to an unacceptably low level. The result is frustrated subscribers and angry system operators.
Therefore, a need exists for a method and apparatus for regulating the delivery of BCMCS by a BCMCS Controller to a BS.

Method and apparatus for regulating a delivery of a broadcast-multicast service in a packet data communication system


An amplifier which comprises an operational amplifier, a semiconductor switch that selectively connects at least one circuit to an input terminal of the operational amplifier, and a device for virtual shorting of both terminals of the semiconductor switch in an isolated state.

Variable gain amplifiers and rooting amplifiers are amplifiers that use switches. The switches used by these amplifiers are mechanical switches such as reed relays and semiconductor switches (e.g., solid state relays, photoMOS relays, and CMOS analog switches). When compared to semiconductor switches, mechanical relays are large and have a short service life. On the other hand, semiconductor switches are small and have a long service life. However, semiconductor switches pose the following problems when used in variable gain amplifiers or rooting devices. First, the "on" resistance of a semiconductor switch is a source of gain error. Moreover, the nonlinearity of the "on" resistance of a semiconductor switch is a source of harmonic distortion. Furthermore, the capacitance between terminals of a semiconductor switch is a source of "off" isolation reduction at high frequency. In addition, the nonlinearity of the capacitance between terminals of a semiconductor switch is a source of harmonic distortion. It should be noted that the capacitance between the terminals of a semiconductor switch is the capacitance between the terminals of transmission path terminals.
Amplifiers that solve several of these problems have been proposed in recent years (for instance, refer to JP (Kokai) 2001-298,337).
However, the problems attributed to the capacitance between terminals of semiconductor switches have, of course, gone unsolved.
Therefore, the present invention solves the problems of amplifiers with semiconductor switches attributed to the capacitance between terminals of the semiconductor switch. Moreover, the present invention simplifies the adjustment of input impedance of amplifiers with semiconductor switches while solving the problems attributed to the capacitance between electrodes.

Low distortion variable gain and rooting amplifier with solid state relay


There is provided a printed circuit board including (a) at least one dielectric layer, (b) at least two metal layers one of which acts as a ground layer, another one of which acts as a power-supplying layer, and the others of which, if any, act as a wiring layer in which a signal pattern is formed, the dielectric layer and the metal layers being alternately formed one on another, and (c) at least one resistor disposed at a marginal end of the printed circuit board between the ground layer and the power-supplying layer, the resistor having a function of disallowing current communication between the ground layer and the power-supplying layer. The above-mentioned printed circuit board prevents fluctuation in a voltage between ground and a power-supply, and further prevents unintentional electromagnetic interference and circuit malfunction caused by invasion of external electromagnetic field thereinto.

1. Field of the Invention
The invention relates to a multi-layered printed circuit board including two or more layers therein, used for an electronic device such as a data processing apparatus and a communication apparatus, and more particularly to such a printed circuit board capable of preventing unintentional electromagnetic interference and also depressing circuit malfunction caused by electromagnetic noises intruding thereto from outside.
2. Description of the Related Art
With recent development of network system, various problems are posed such as unintentional electromagnetic interference (EMI) generated by operation of electronic devices such as a data processing device and communication device, interference to other radio-communication systems by such EMI, and malfunction of electronic devices caused by intrusion of external electromagnetic waves thereinto.
In order to overcome those problems, electronic devices are sealed, for instance, with a filter for preventing electromagnetic interference from emitting therefrom and external electromagnetic waves from intruding thereinto. To seal a printed circuit board on which an electronic circuit, a major part of an electronic device, is mounted brings an advantage in terms of a cost, and hence various attempts have been made for that purpose.
For instance, one of conventional multi-layered printed circuit boards has been suggested in Japanese Unexamined Patent Publication No. 5-243782. FIG. 1 is a cross-sectional view of the suggested multi-layered printed circuit board. A multi-layered printed circuit board 101 includes a signal transmission layer 102, an internal earth layer 104 located above the signal transmission layer 102, an earth layer 105 located above the signal transmission layer 102, and an insulator 103 filled between an upper surface layer 100 and the earth layer 105. An amplifier circuit 99 is mounted on the upper surface layer 100.
Japanese Unexamined Utility Model Publication No. 60-71174 has suggested another multi-layered printed circuit board. As illustrated in FIG. 2, the suggested multi-layered printed circuit board 106 includes power-supplying lines 109 and 110 connected to a power-supply, a plurality of insulating substrates 108 deposited one on another between the power-supplying lines 109 and 110, and signal layers 107 (shown with a broken line) electrically connecting elements, mounted on the printed circuit board 106, with each other. The signal layers 107 are formed in the insulating substrates 107 to thereby isolate the signal layers 107 from circumstances.
FIG. 3 illustrates a multi-layered printed circuit board suggested in Japanese Unexamined Utility Model Publication No. 5-76083. The suggested printed circuit board 111 includes a pair of outer surface layers 140, and signal pattern layers 141a, 141b, 141c and 141d formed between the outer surface layers 140. The outer surface layers 140 are designed to have a ground pattern or a solid pattern in order to act as a shield, thereby preventing emission of electromagnetic waves from the signal pattern layers 141a to 141d.
FIG. 4 illustrates a multi-layered printed circuit board suggested in Japanese Unexamined Patent Publication No. 2-68571. The suggested printed circuit board 112 includes a first insulating layer 142, a first signal pattern layer 143, a second insulating layer 144, a second signal pattern layer 145, a substrate 146, and a shield layer 113, deposited in this order. A device 147 is mounted on the shield layer 113, but is designed to make no electrical communication with the shield layer 113.
FIG. 5 illustrates a multi-layered printed circuit board suggested in Japanese Unexamined Utility Model Publication No. 59-146999. In accordance with the suggested printed circuit board 114, signal layers 116 are sandwiched between ground or power-supplying layers 115.
FIG. 6 illustrates a structure for packaging an electronic device therein suggested in Japanese Unexamined Utility Model Publication No. 2-26294. A transformer 148 comprising a core 149 and a coil 150 wound around the core 149 is placed in a case 151. On the transformer 148 is mounted a multi-layered printed circuit board 121. The multi-layered printed circuit board 121 is designed to have a lowermost layer as a shield layer 122. Since the shield layer 122 is located closest to the core 149 or a source of emission of electromagnetic waves, the shield layer 122 shuts out noises derived from the core 149.
FIG. 7 illustrates a structure for packaging an electronic device therein suggested in Japanese Unexamined Patent Publication No. 6-69680. A multi-layered printed circuit board 124 is designed to have outer surface layers as shield layers 125a and 125b. The multi-layered printed circuit board 124 is mounted in a metal box 126 to thereby define a space between the printed circuit board 124 and a bottom surface of the metal box 126. A source 127a of emission of high frequency electromagnetic waves and a circuit 127b are disposed in the space to thereby shield EMI source.
FIG. 8 is a top plan view illustrating a printed circuit board suggested in Japanese Unexamined Patent Publication No. 7-302956. The illustrated printed circuit board has a substrate 128 on which conductors 130A and 130B are formed at a marginal end thereof, both of which define a rectangular-shaped conductor. A plurality of conductors 130D extend in a lengthwise direction of the rectangular conductor 130A and 130B, and a plurality of intermediate conductors 130E extend in the same direction between the conductors 130D. On the substrate 128 are formed an oscillator 152, and integrated circuits 153a and 153b. The oscillator 152 and the integrated circuits 153a, 153b are electrically connected to one another by a clock line 154. The substrate 128 is formed with a rectangular opening 129 having a width W.sub.1 and located at a distance L.sub.4 from the conductor 130A. The rectangular opening 129 divides the intermediate conductors 130E into pieces, and hence define a non-conductive region. The rectangular opening 129 is located remote from the conductors 130A and 130B by a distance of one-fourth or greater of lengths of the conductors 130A and 130B, respectively.
FIG. 9 illustrates a multi-layered printed circuit board suggested by Y Akiba, Proceedings of the 10th Japan Institute for Interconnecting and Packaging Electronic Circuits Annual Meeting, 15B-12, pp. 175-176. The illustrated printed circuit board 131 includes first and second ground layers 132 and 133 between which is interposed a resistor 135. A power-supplying layer 160 is sandwiched between the ground layers 132 and 133. A dielectric substance 161 disposed between the ground layers 132 and 133 is designed to have a dielectric constant .epsilon.1 greater than .epsilon.2 of other dielectric substance 162 disposed between the power-supplying layer 3 and the ground layer 133 in order to obtain a great capacity between the power-supplying layer 3 and the ground layer 132.
There are two major factors for unintentional electromagnetic interference from a printed circuit board and malfunction of a circuit caused by intrusion of external electromagnetic field thereinto. One of them is a loop defined by a signal wiring pattern and a ground pattern, and the other is fluctuation in voltage between a power-supply and ground.
The printed circuit boards illustrated in FIGS. 1 to 5 attempt to prevent unintentional electromagnetic interference and intrusion of external electromagnetic field both caused by the firstly mentioned factor, namely a loop defined by a signal wiring pattern and a ground pattern. Those printed circuit boards attempt to electrically shield a loop defined by a signal wiring pattern and a ground pattern by the ground layer formed all over a substrate, the ground pattern partially formed on a substrate, or the signal wiring pattern sandwiched between metal plates having the same potential as that of a power-supplying layer and a power-supplying pattern layer. However, those printed circuit boards have a problem that layers having the same potential as that of ground or a power-supply have to be additionally formed for sandwiching a signal wiring pattern layer therebetween.
The printed circuit board illustrated in FIGS. 6 and 7 are designed to have a layer or layers as an entire ground layer or as a shield plate to thereby define a space between the shield plate and a metal housing. A high frequency circuit which is a source of EMI is placed in the space to thereby prevent EMI therefrom and intrusion of external electromagnetic waves thereinto.
However, in the above-mentioned structure where a layer or layers of the printed circuit board cooperate(s) with a housing to thereby define a shield, the printed circuit board has to be fabricated so as to be able to assemble with a particular housing. Hence, the printed circuit board one fabricated to do so cannot be applied to existing housings.
The printed circuit board illustrated in FIG. 8 divides the power-supplying pattern and ground pattern into pieces by means of the intermediate non-conductors 129 to thereby prevent resonance caused in dependence on a length of those patterns. However, if the power-supplying pattern or a ground pattern were designed to entirely cover a substrate therewith, the non-conductors 129 inversely act as a slit antenna, resulting in increased EMI.
The multi-layered printed circuit board illustrated in FIG. 9 incorporates the resistor 135 as loss material into a high frequency circuit defined by the first and second ground layers 132, 133 and the power-supplying layer 160 to thereby prevent EMI and malfunction of devices both caused by fluctuation in a voltage between the power-supplying layer 160 and the first and second ground layers 132, 133. However, the printed circuit board has a problem that an additional ground layer has to be formed other than an ordinary ground layer, resulting in an increase in fabrication cost.

Printed circuit board for prevention of unintentional electromagnetic interference


An internal combustion engine idle air control system including an idle air control actuator coupled to an idle air control valve for varying the position of the valve within an engine intake air passage for engine inlet air control under idle operating conditions adjusts the time rate of change in position of the idle air control valve in response to change in barometric pressure to account for change in air density passing across the valve and to account for change in torque load acting against the valve to precisely respond to torque load changes during idle operations without violating idle air control actuator stability margins.

Internal combustion engine idle air control systems are known to precisely meter inlet air to cylinders of the engine in response to a difference between actual engine speed and a relatively low target engine speed. Change in engine torque load, for example resulting from change in accessory load, can perturb engine speed away from the target speed. A desirable engine idle air control system can reject typical changes in engine torque load to provide a stable engine speed that is pleasing to a vehicle operator.
Certain engine torque load changes can occur very rapidly. For example, substantially a step change in torque load can occur during certain transient maneuvers. To reject such rapid torque load changes, an engine idle air control system must be very responsive. Effort has been made in conventional systems to assess system response limits and then to push system response to the limits in response to a detected rapid torque load change to provide precise transient control of idle speed throughout the load change or, more specifically, to minimize the difference between the target and actual engine speeds throughout the transient maneuver.
It has been determined that the response limit of an engine idle air control system changes with change in barometric pressure. It has further been determined that the response requirements of the idle air control system change with change in barometric pressure. More specifically, in engine idle air control systems including an actuator coupled to a valve for metering air to the engine, the speed at which the actuator can be accurately driven is constrained by the load acting against the valve. The load acting against the valve increases with increasing barometric pressure. Conventional engine idle air control systems prescribe a fixed actuator speed over all barometric pressures. Accordingly, to provide for accurate actuator control, a worst case actuator speed is prescribed, which is a speed determined under high barometric pressure conditions. In such systems, untapped actuator performance capability remains under barometric pressure conditions below such high barometric pressure conditions.
To reject an engine load change, a corresponding change in engine torque is administered by changing an amount of fuel and air admitted to engine cylinders. The engine idle air control system provides for a desired time rate of change in intake air. The fuel control system reacts to the time rate of change in intake air to provide a corresponding time rate of change in injected fuel. As barometric pressure changes, the change in air density affects the amount of intake air passed to the engine for a given state of the idle air control system. As barometric pressure increases, for example, more air is admitted to the engine for a given state, and less change in position of a valve of the engine idle air control system is needed to provide for a desired time rate of change in intake air. Conventional systems prescribe, in response to a change in engine load, a change in position of the valve of the idle air control system at a single rate, which leads to, under varying barometric pressure conditions, significant variation in the time rate of change in air admitted to the engine. Substantially sub-optimized idle air control performance results, for example when responding to an engine load change under barometric pressure that is significantly different than a calibration pressure.
It would therefore be desirable to account for the effect of change in barometric pressure in engine idle air control, to maximize, when necessary, the responsiveness of the control, and to improve control accuracy.


A dielectric barrier discharge lamp with a discharge vessel (1) has at least one inner electrode (5a; 5b) which is covered with a dielectric layer (6a; 6b) and is arranged on the inner side of the discharge vessel (1) The at least one inner electrode (5a; 5b) is electrically conductively connected to a supply conductor (8a; 8b) in a leadthrough region, the leadthrough region being realized by a gastight pinch (9).

U.S. Pat. No. 6,097,155 has disclosed a tubular barrier discharge lamp with at least one inner electrode in strip form. One end of the tubular discharge vessel of the lamp is closed off in a gastight manner by a stopper which is fused to part of the inner wall of the discharge vessel by means of soldering glass. The strip-like inner electrode runs to the outside as a supply conductor, through the soldering glass. One drawback is that an additional soldering glass layer, as a gastight joining means, is required between stopper and vessel wall. Moreover, it is necessary to maintain tight tolerances in order to minimize scrap caused by leaks at the stopper seal.
US-A 2002/0163306 has disclosed a tubular barrier discharge lamp with inner electrodes in strip form. At the end of the electrode leadthroughs, the discharge tube is closed off in a gastight manner with the aid of a disk-like closure element which does not use any connecting means. For this purpose, at this end the discharge tube is provided with a constriction which surrounds the edge of the disk-like closure element in the form of a ring. Then, the constriction and the disk-like closure element are fused together in a gastight manner, with the inner electrodes leading out through this fused joint. A drawback of this arrangement is the relatively high production costs.

Dielectric barrier discharge lamp with pinch seal

Patent-Treuhand-Gesellschaft fuer Elektrische Gluehlampen mbH


A window linking system is provided that links windows on a video display to reduced window clutter. When two windows are linked, the linked windows combine to form one larger window, known as an aggregate window, that is manipulated as a single window. By linking windows together, fewer individual windows are contained on the workspace of a video display, which reduces window clutter and which allows a user to more easily reorganize their workspace since fewer windows require manipulation. The window linking system implements window linking by using a container. A "container" is a screen object like a window to which another window, called a docking window, can be linked. The window linking system detects when a docking window is attempting to be linked with a container by determining whether the docking window is being dropped at the border of the container. If the docking window is being dropped at the border of the container, the window linking system links the docking window with the container, displaying both the container and the docking window adjacent to each other. After being linked, the linked windows form an aggregate window that is manipulated as a single window. As such, all resizing of the aggregate window, movement of the aggregate window, minimization of the aggregate window, and maximization of the aggregate window is applied to the aggregate window as a whole, including both the container and the docking window.

A "window" is a specially delineated area of a video display that is typically used to display information, such as a document or a message, to a user. Each window acts independently, as if it were a virtual display device, and each window is manipulated independently. The manipulations performed on a window include resizing the window or moving the window. A program, like an operating system or an application program, may display one or more windows.
FIG. 1 depicts a conventional window 100. The window 100 has a display area 110 that displays window contents, such as the text of a document, and a title bar 102 that displays meaningful information, like a title, to the user so that the user can identify the purpose of the window. Sometimes a window 100 may display a scroll bar when the window has more contents than can be displayed in the display area 110 at one time. The title bar 102 has a number of buttons 104, 106 and 108. Button 104 is used to close the window. When the window 100 is associated with an application program that displays only one window, activation of button 104 terminates both the window and the application program. Button 106 is used to enlarge the window so that it covers more of the video display. After being enlarged to cover the entire screen of the video display, button 106 can be activated again to return the window to its original size. When button 106 is used in this capacity, it is known as a "restore" button. Button 108 is used to minimize the representation of the window 100. The phrase "minimizing a window" refers to representing the window in a manner which is not fully functional, like representing the window as an icon or as a button. Once minimized, double-clicking on the icon maximizes the window 100 into a fully-functional representation of the window.
Some windowing systems, such as the Microsoft.RTM. Windows.RTM. 95 operating system from Microsoft Corporation of Redmond, Wash., are message based such that operations are achieved by passing messages between windows. In these systems, a window is created based upon a window class that identifies a window procedure which processes messages that are sent to the window. The windowing system supports a RegisterClass() function that enables an application program to register window classes.
In general, each application program in the windowing system with a user interface has an associated window procedure for each window that the application program displays. For each application program having a user interface, the windowing system maintains a message queue. When an event occurs, the event is translated into a message that is put into the message queue for the application program. Such an event includes keystrokes, timer events, manipulation of the mouse cursor, or manipulation of the mouse button. The "mouse cursor" reflects movements of a mouse input device on the video display. The mouse input device typically has a mouse button that activates the mouse. For example, when the user depresses the mouse button to activate the mouse, the operating system generates a "MOUSE.sub.-- DOWN" event and sends a corresponding message to the message queue of the application program. The application program retrieves and delivers messages in the message queue to the proper window procedure for processing (i.e., the window procedure of the window for which the event is intended). The window procedure, in turn, has a number of functions that the window procedure invokes depending on the specific event that has occurred. For example, the window procedure for a word processing program may invoke a specific function when both a MOUSE.sub.-- DOWN event has been received and the mouse cursor is within the display area of the window. Such a function may, for example, begin highlighting the text to indicate that the highlighted text is being selected. Since the message queue maintains the messages received from the windowing system, during the processing of functions invoked from a window procedure, the functions can make requests of the message queue to retrieve messages from the message queue.
The windowing system provides the ability to "subclass" either a control or another window. A "control" is a screen object, like a button or a scroll bar, that can be manipulated by the user to perform an action. A window sometimes contains one or more controls. The controls of the windowing system act much like windows by receiving messages from the windowing system. When subclassing a control or a window, the windowing system allows a program to receive all of the messages destined for that control or window. This technique is advantageous when a window displays a control on another window. For example, to integrate a scroll bar into the functionality of a window, the window needs to manage the operations of the scroll bar and, thus, needs to intercept the messages destined for the scroll bar to control its functionality. By intercepting the messages through subclassing, the program determines how the scroll bar behaves in response to a given message.
Although some application programs display many windows, the available space on the video display, known as the work space, is limited. As the number of windows displayed on the video display increases, it becomes more difficult for the user to perform their work on the workspace of the video display, as the workspace appears cluttered, much like a desk appears cluttered when lots of papers are strewn across it. Window clutter makes it more difficult for the user to perform their work, and thus, it is desirable to reduce window clutter.


The present invention relates to a power-saving method in a wireless communication system. In a power-saving method for a terminal of a wireless communication system according to one aspect of the present invention, the terminal receives configuration information relating to power-saving from a base station and operates in a power-down mode in which receive processing is not carried out in accordance with the configuration information relating to power saving; and the configuration information comprises at least one or other of information relating to a time point at which the base station is not transmitting packets to the terminal and a time point at which the base station is transmitting packets to the terminal.

In the related wireless communication system, since a modem of a user equipment is unaware of when a signal is to be transmitted, the modem is always in a stand-by mode in order to receive a signal whenever transmitted. Therefore, in the related art wireless communication system, excessive power consumption occurs. More specifically, since the modem does not know when a packet will be transmitted, the user equipment is required to be operated in full power starting from the RF to the baseband processing at all times. Also, the user equipment determines whether or not a signal is being received. And, when it is determined that a signal is received, the user equipment uses the output of the baseband processing. And, when it is determined that a signal is not received, the user equipment discards the output.
The operations of the modem are generally performed while the user equipment is in a state ready to receive a packet. Accordingly, most of the power related to the reception unit is insignificantly wasted. Most particularly, such problem becomes more critical when the user equipment received a streaming service or an audio service.
Even while the user equipment performs a voice communication process, the user equipment is required to monitor traffic during all times in order to achieve instructions such as the reception of other data traffic or the delivery related to any re-transmission, delivery related to readjustment of resources, and so on. And, the power required for monitoring the traffic is mostly consumed and wasted insignificantly. Thus, the related art user equipment is disadvantageous in that, while a user is making a voice call (or phone call), the user equipment consumes an excessive amount of power as compared to the actual existing traffic.
Such disadvantage in the user equipment also occurs when the user equipment uses a streaming service. Therefore, a method preventing the user equipment from excessively consuming and wasting power, when the user equipment is using such services, or even while the user equipment is performing any other operations, is required to be developed.

Power saving method in a wireless communication system


A switch (10) is provided that has a housing (12), an actuator (20), a contact blade (18), first and second shape-memory wires (28,30), and first and second contact points (70,71). The actuator (20) has a first end portion (52) pivotally coupled to the housing (12), and a second end portion (22) with first and second generally opposed arm portions (24), (26) extending therefrom. The contact blade (18) has the first contact point (70) positioned thereon, and is coupled to and moveable with the actuator (20). The first and second shape-memory wires (28,30) respectively extend between the first and second arm portions (24,26) of the actuator (20) and the housing (12). The second contact point (71) is coupled to the housing (12) and is electrically engageable with the first contact point (70) in response to movement of the actuator (20).

1. Field of the Invention
This invention relates generally to electrical switches, relays, and the like and, more particularly, to an electrical switch actuated by a shape-memory wire.
2. Description of the Related Art
Electrical switches and relays are now widely used in nearly all industries, and consequently, are produced in enormous quantities. Their wide use has made reliable operation and long life important factors in their design. Switches and relays have tended to be complex in mechanical design. Complex mechanical design, however, commonly results in devices that are difficult to assemble, and are prone to shortened life spans and unreliable operation.
Moreover, because so many switches and relays are manufactured, even a relatively modest cost savings per unit can still amount to substantial savings, when the switch is produced in mass quantities. Complex mechanical designs tend to be expensive because of the manufacturing requirements for the various parts and because of the difficulty commonly associated with their assembly.
The present invention is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above.


There is disclosed a lamp device including a longitudinal axis, a first elongate electrical connector and a second elongate electrical connector, each of the first elongate electrical connector and the second elongate connector being non-parallel with respect to the longitudinal axis. The present lamp device provides a reliable electric connection on the one hand, yet is relatively inexpensive, uncomplicated and simple to implement on the other hand.

1. Field of the Invention
In one of its aspects, the present invention relates to a lamp device. In another of its aspects, the present invention relates to a radiation lamp. In yet another of its aspects, the present invention relates to a radiation source assembly. In yet another of its aspects, the present invention relates to a radiation source module. In yet another of its aspects, the present invention relates to a fluid treatment system. In yet another of its aspects, the present invention relates to a water disinfection system.
2. Background Information
Fluid treatment systems such as water disinfection systems are generally known in the art.
See, for example, one or more of the following United States patents:
U.S. Pat. No. Re36,896,
U.S. Pat. No. 3,418,370,
U.S. Pat. No. 4,482,809,
U.S. Pat. No. 4,872,980,
U.S. Pat. No. 5,006,244,
U.S. Pat. No. 5,471,063,
U.S. Pat. No. 5,504,355,
U.S. Pat. No. 5,538,210,
U.S. Pat. No. 6,342,188,
U.S. Pat. No. 6,500,346,
U.S. Pat. No. 6,507,028,
U.S. Pat. No. 6,646,269,
U.S. Pat. No. 6,674,084,
U.S. Pat. No. 6,803,586, and
U.S. Pat. No. 6,863,078.
Many of the above-identified United States patents teach fluid treatment systems that employ ultraviolet (UV) radiation to kill, sterilize and/or prevent replication of microorganisms (bacteria, viruses, pathogens and the like) that may be present in the fluid.
Generally, such conventional fluid treatment systems employ an ultraviolet radiation lamp to emit radiation of a particular wavelength or range of wavelengths (usually between 185 and 400 nm) to kill, sterilize and/or prevent replication of microorganisms (bacteria, viruses, pathogens and the like) that may be present in the fluid.
Conventional ultraviolet radiation lamps include low pressure lamps, medium pressure lamps, low pressure high output lamps and the like.
In more recent years, it has become conventional to use such ultraviolet lamps configured to have all of the electrical connections disposed at one end of the lamp. See, for example, FIGS. 2-8 of U.S. Pat. No. 4,700,101 [Ellner et al. (Ellner)] and FIGS. 1, 2 and 4 of U.S. Pat. No. 5,166,527 [Solymar].
As can be seen from the conventional radiation lamps taught by Ellner and Solymar, the electrical connection pins are elongate and are disposed such that the axes of the pins are parallel with the longitudinal axes of radiation lamp. In other words, the electrical connection is made by pushing an end cap or other connection base on to the pins in a direction parallel to the longitudinal axis of the radiation lamp.
The problem with this approach is that in many applications, the radiation lamp is immersed in a flow of water and turbulence created within that water treatment system invariably imparts a vibratory motion to the lamps which frequently results in lamps being vibrated or shaken loose of its electrical connection base or socket thereby causing the lamps to be rendered completely or intermittently inoperative. When such an event occurs, the water being treated may not be fully disinfected.
More recently, other attempts to address this problem have used a relatively complicated mechanical connection (e.g., a so-called "push-and-twist" connection) to secure the lamp to the connection base. See, for example, U.S. Pat. No. 5,422,487 [Sauska et al (Sauska)] and U.S. Pat. No. 6,884,103 [Kovacs]. The problem with these approaches is the complexity of the mechanical connection between the lamp and the base unit requiring the use of springs, specialized connection lugs and the like. Further, a connection system which is predicated on a dual motion system such that pushing and twisting gives rise to a higher incidents of lamp breakage and other damage to the module by field personal.
Accordingly, there remains the need in the art for a lamp device, particularly a radiation lamp, which will provide a reliable electric connection on the one hand, yet be relatively inexpensive, uncomplicated and simple to implement on the other hand.

Radiation lamp and radiation source module incorporating same


The present invention relates to the use of specific compounds related to the indolocarbazole K252a, for the preparation of pharmaceutical compositions for the treatment of various forms of cancer.

Intracellular phosphorylation events have a decisive impact on the longterm outcome of various pathological conditions by modulating the survival of cells subjected to genetic or environmental insults. In particular, inappropriate activation of certain kinases critically involved in the regulation of the cell cycle, or in the case of postmitotic cells like neurons, in the maintenance of the respective differentiation states, can undermine beneficial physiological responses to a pathological challenge, like apoptosis of cancer cells or neuronal recovery under metabolic stress.
It has become appreciated that certain key kinases, like those belonging to the cell cycle regulated or MAP-kinase superfamilies, are ubiquitously expressed but perform fundamentally different functions in different biological contexts. In proliferating cell types, the physiological activation of such kinases tends to exert a dominant control over cell proliferation, either by synchronizing intracellular events (cdks) or by integrating environmental stimuli and intercellular signals (MAP-kinases). Therefore, intervention on the level of such kinases has therapeutic utility in a variety of cancers.
The involvement of the key MAP-kinase ERK2 and several members of the cdk family in cancer biology is amply documented. Constitutively activated ERK1/2 proteins are a frequent abnormality, e.g., in melanoma cells, often caused by mutation of a membrane receptor coupled to the ERK signal transduction pathways [Abi-Habib et al., Mol. Cancer. Ther. 4, 1303-1310 (2005); Takata et al., J. Invest. Dermatol. 125, 318-322 (2005)]. For most tumor cells with this abnormality, inhibition of the ERK-pathway is toxic. Constitutively activating receptor mutations are a common theme in tumor biology, and a large number of such receptors feed into the ERK pathway. One of the widely known examples are mutations in the signaling molecule ras upstream of the ERK cascade, which account for a sizeable fraction of cancers across the spectrum of originating tissues. Prominent in breast cancer are mutations in the ERB family of tyrosine kinase receptors. However, Tykerb, a new agent used for treatment of Herceptin resistant tumors, shows growth inhibitory activity only in about 20% of a large panel of breast cancer tumor cell lines, in spite of having dual specificity for two ERB receptor subtypes [Konecny et al., Cancer Res. 66, 1630-1639 (2006)]. In contrast, all of the cell lines tested had some level of constitutive ERK2 activity. Thus, intervention on the level of ERK, however, should provide for a more universal therapeutic principle than targeting a myriad of sometimes still unknown upstream receptors with oncogenic mutations [e.g., Zuidervaart et al., Br. J. Cancer 92, 2032-2038 (2005)]. De novo or emerging resistance to other more specific intervention strategies [e.g., Gee et al., Endocr. Relat. Cancer 12 Suppl., S99-S111 (2005)] may also be much less of a problem at the level of ERK2: the homology of ERK2 across mammalian species is virtually absolute, indicating either the absence of mutagenic activity in the respective gene, or a lack of tolerance for any alterations of the protein. Clinical utility of specific interference with ERK activity has recently been demonstrated in patients with advanced malignancies by treatment with an inhibitor of the only known upstream activating kinase of ERKs, termed MEK1/2, thus acting as a proxy for inhibition of ERKs [Lorusso et al., J. Clin. Oncol. 23, 5281-5293 (2005)]. However, even with the clearly very central role of the MAP-kinase pathway in tumor cell transformation, surprising limitations of efficacy of highly specific inhibitors of MEK1/2, and thereby ERK2, have become apparent. While such inhibitors are quite effective in raf-transformed cells, they were shown to loose efficacy in tumor cells harboring oncogenic ras-mutations [Solit et al., Nature 439, 358-362 (2006)], where apparently another pathway besides the MAP-kinase cascade is utilized to provide sufficient transforming activity. This is particularly serious in view of the fact that more than 50% of all known tumors include oncogenic mutations of Ras, thereby providing ample opportunity for unpredictable efficacy or emergence of resistance in recurrent tumors.
There is an urgent need for more broadly acting inhibitors, addressing the ERK pathway, but also preventing the by-pass observed in a majority of clinical cancers. Such inhibitors should finally show the broad therapeutic utility in cancers presenting a broad spectrum of molecular oncogenic mechanisms, and thereby affect the clinically most important outcome of patient survival.

Compositions and methods for the treatment of cancer


The present invention is for an apparatus that receives input data at a non-uniform first data rate carried by a system clock, and provides output data at a substantially uniform second data rate that is nominally equal to the first data rate and is also carried by the system clock. The system clock is faster than the first or second data rates and accordingly, a write enable signal controls the input data that is written into a saturating elastic store and a read enable signal controls the reading and output of data from the saturating elastic store. The saturating elastic store includes a plurality of storage locations and provides a storage fill level indicative of the amount of storage locations currently holding data. A digital filter receives the storage fill level and filters the storage fill level to provide a control word to a digitally controlled read enable signal generator. The digitally controlled read enable signal generator provides a read enable signal that is nominally the second data rate and that can be varied about the nominal second data rate in response to the control word. The digitally controlled read enable signal generator is able to vary the read enable signal rate by providing a plurality of stuff bit opportunities interspersed between the read enable signals. Some of these stuff bit opportunities are filled to set the read enable signal rate at the nominal second data rate value. By filling or not filling the stuff bit opportunities, the read enable signal rate can be adjusted over a narrow band of frequencies.

This invention relates to a data communications device and in particular to a jitter and wander reduction apparatus.
In a synchronous communications network, digital payload data is carried on a particular clock frequency within a synchronous message format. This payload data may include both asynchronous digital data and synchronous digital data originating at a different data rate in a foreign digital network. The Synchronous Optical Network (SONET) and its European counterpart the Synchronous Digital Hierarchy (SDH) provide a standard format of transporting digital signals having various data rates, such as a DS-0, DS-1, DS-1C, DS-2, or a DS-3 signal and their European counterparts within a Synchronous Payload Envelope (SPE), or a container that is a part of a SONET/SDH STS-N/STM-N message frame. In addition to the digital data that is mapped and framed within the SPE or container, the STS-N/STM-N message frame also includes transport and overhead data that provides for coordination between various network elements.
If the digital data that is mapped and framed in the STS-N/STM-N message was originally carried by a clock signal having a different frequency than the SONET/SDH line rate clock, certain adjustments to the framed digital data must be made. For example, if a DS-3 data signal, which is carried by a 44.736 MHz DS-3 clock signal is to be carried in a SONET/SDH fiber-optic network, the DS-3 signal is mapped into the higher rate SPE of an STS-1 message, and extra bits must be added to the DS-3 signal prior to transmission through the SONET/SDH network. These extra bits are commonly referred to as stuff bits and are merely place markers and in general carry no valid data. These gap bits are required because the DS-3 signal is slower than the SONET/SDH clock frequency so that there are not enough DS-3 bits at the higher frequency to form a complete SONET frame. More detail may be found in the Bellcore specification "SONET Transport Systems: Common Generic Criteria", GR-253-CORE, Issue 3, September 2000, the Bellcore specification "Transport Systems Generic Requirements (TSGR): Common Requirements", GR-499-CORE, Issue 2, December 1998, and the ITU-T Recommendation G.783, "Characteristics of Synchronous Digital Hierarchy (SDH) Equipment Functional Blocks", January 1994.
When the STS-1 message is received at a network exit node, the overhead bytes are removed from the SONET STS-1 message and replaced by gaps in the data stream. The payload data that remains is de-framed and de-mapped into a data stream carried by a higher clock frequency than the nominal original clock frequency of the payload data. Thus the stuff data that was inserted when the data was mapped into the SPE remains when the data stream is recovered from the SPE and is also replaced by gaps in the data stream. Thus, the recovered payload data contains gaps in the data stream remaining after the overhead bytes and stuff data bits have been removed. If, for example, DS-3 data has been transported via a SONET/SDH network, the DS-3 data must be converted from the SONET clock signal to the lower frequency DS-3 clock signal and the gap data bits must be removed prior to the DS-3 signal being B3ZS-encoded for electrical re-transmission.
To transfer data from one clock domain to another, for example from the DS-3 embedded within the SONET signal rate to the proper DS-3 signal rate, typically a desynchronizer is used to provide a buffering mechanism between the clock domains. A desynchronizer typically includes an elastic store first-in-first-out memory buffer that receives gapped data recovered from a synchronized data payload as an input at one clock frequency and stores the data in appropriate storage locations. Data is read from the elastic store buffer at a different clock frequency and is provided as output data at that frequency. This output data does not contain the gap data bits that were added when the slower signal was mapped into the faster SONET/SDH STS-1 message.
Once the data has been de-mapped and de-framed from the SPE and the gaps removed, a phase locked loop (PLL) is typically used to recover the clock information and to adjust the read signal associated with the data stored in the elastic store for transmission downstream as a data signal carried by a smooth clock signal.
However, not all applications require the extraction of the uniform PDH clock signal for output. For example, the PDH data coming from the de-mapper can be put into another SONET STS message or in some cases may be output without desynchronization. In these circumstances, the data can be carried by the SONET transport clock or a related clock used by the de-mapper. However, the non-uniformity of the data must be maintained within certain bounds that are specified by the standards listed above. One way to maintain the data within these standards is to fully desynchronize the data, even though the application may not require desynchronized data. Although this method will certainly work, the additional hardware expense of the full desynchronizer including a loop filter, VCXO, etc. will add to the overall expense of the system. In addition, some applications require a fully integrated system and since it is difficult to produce a fully integrated version of a VCXO, using a full desynchronizer is not a viable option.
Thus it would be advantageous to provide a system for processing a PDH payload extracted from the SPE without fully desynchronizing the resulting data stream and extracting a uniform PDH clock.