A hybrid circuit for a full-duplex transceiver includes a two-to-four wire ratio converter (50, Z1, Z2) for forwarding a transmitted signal TX′ on a transmission line (41) in response to an input signal TX. The ratio converter also produces a signal RXA in response to a received signal RX arriving on the transmission line, wherein signal RXA includes an echo of input signal TX. A passive filter (H1) and a first active filter (H2) each filter input signal TX to generate signals TXA and TXB summed with the RXA signal to form a signal RXB at the input of an amplifier (52, Z3, Z4) producing an output signal RXC. A second active filter (H3) filters input signal TX to generate a signal TXC summed with the RXC signal to produce the output signal RX. The impedance of the passive filter is designed so that when the transmission line has a target impedance, such as the impedance of an ideal twisted pair, the TXA output signal of the passive filter adequately offsets the TX signal echo in RXA. A control circuit monitors the residual echo in the output signal and, when the transmission line impedance varies from its target value so that the passive filter alone cannot provide adequate echo cancellation, the control circuit turns on the first and/or second active filters to provide additional echo cancellation. The frequency responses of the active filters are adjustable to accommodate a variety of transmission line impedances.

1. Field of the Invention
The invention relates to transceivers providing full-duplex communication and in particular to a hybrid circuit for a full-duplex transceiver.
2. Description of Related Art
Conventional modems operating in accordance with an Asymmetrical Digital Subscriber Line (ADSL) standard incorporate an echo canceling hybrid circuit for combining a transmit signal with a receive signal in an ADSL transceiver to enable bidirectional data communication through a two-wire transmission line, such as, for example, an unshielded twist wire pair. The hybrid circuit cancels the echo signal caused by a portion of the transmit signal appearing in the receive signal as noise.
FIG. 1 shows a typical prior art transceiver 10 for forwarding an input signal TX as a transmitted signal TX′ to a remote transceiver (not shown) via a transmission line 12, and for generating an output signal RX in response to a received signal RX′ arriving on line 12 from the remote transceiver. Transceiver 10 includes an amplifier 11, for amplifying the input TX signal, a summing amplifier 16 for generating the output RX signal, and a hybrid circuit 18 for coupling transmission line 12 to the output of amplifier 11 and the input of amplifier 16. Hybrid circuit 18 includes an impedance element Z1 and a transformer 14 coupling the output of amplifier 11 to line 12. Transformer 14 also couples a non-inverting input of amplifier 16 to line 12. Both the received and transmitted signals RX′ and TX′ on line 12 appear as components of a signal VIN at the non-inverting input of summing amplifier 16. Hybrid circuit 18 also includes a voltage divider network comprising impedance elements Z2 and Z3 to provide an offset signal VOFF at an inverting input of amplifier 16 to offset the transmitted signal component of the VIN signal. The VOFF signal will cancel the echo of transmitted signal TX′ in received signal RX′ when Z1/ZL=Z2/Z3, where ZL is the impedance of transmission line 12.
A modem meeting the ADSL standard uses a frequency division duplex (FDD) scheme wherein the transmitted and received signals TX′ and RX′ on line 12 occupy different frequency bands. For example, for customer premise equipment (CPE) ADSL modem, the transmitted signal occupies the 30 KHz-138 KHz frequency band (the "upstream band") while the received signal occupies the 138 KHz-1.1 MHz frequency band (the "downstream band"). Although the line driver of a CPE modem delivers the transmitted signal over the upstream band, the transmitted signal TX′ inevitably introduces some level of noise and distortion extending above 138 KHz and lying in the downstream band of the received signal RX′. Hybrid circuit 18 does not completely cancel the residual echo of transmit signal TX′ in output signal RX. One portion of this residual echo resides in the transmitted signal's upstream band, and a remaining portion of the residual resides in the received signal's downstream band. Since the residual echo in the receiver band is indistinguishable from the received signal RX′, it can significantly degrade receiver performance.
A filter (a high pass filter in the case of a CPE transceiver) can separate the residual echo in the transmitted band, but if the residual echo is too strong, it can saturate the receiver, particularly its low noise amplifier. Therefore, it is important for a transceiver to include a hybrid circuit providing good echo cancellation to minimize the residual echo in both the upstream and downstream bands. It is not difficult to design a hybrid circuit to provide sufficient echo cancellation in both the transmitter band and the receiver band when line 12 is an ideal twist-pair transmission line. However, a twisted-pair transmission line will often include bridged taps (open-end transmission line stubs) that cause the transmission line impedance to vary significantly with frequency, and the lengths and locations of the bridged taps strongly affect the relationship between transmission line impedance and signal frequency. Designers therefore find it difficult to design a hybrid circuit that can provide good echo cancellation in both the transmitter band and the receiver band that can accommodate a wide variety of transmission line frequency response characteristics. A common solution is to make the impedance element Z3 of hybrid circuit 18 adjustable using several discrete switches to switch resistors and/or capacitors in or out of element Z3 to synthesize an impedance providing a good match to the line impedance.
The following patents describe hybrid circuit topologies addressing transmission line impedance matching problems associated with bridged taps:
U.S. Patent Publication 2003/0147526, filed Aug. 7, 2003 by Oswal et al.
U.S. Patent Publication 2003/0123650, filed Jul. 3, 2003 by Oygang.
U.S. Patent Publication 2003/0169875, filed Sep. 11, 2003 by Lee et al.
U.S. Patent Publication 2003/0169806, filed Sep. 11, 2003 by Warke.
U.S. Pat. No. 6,208,732 issued Mar. 27, 2001 to Muschytz et al.
FIG. 2 illustrates another prior art transceiver 20. An input signal TX drives a differential amplifier 22 driving a transmission line 26 via a hybrid circuit 21 to produce the transmitted signal TX′. Hybrid circuit 21 also couples transmission line 26 to the input of a differential amplifier 28 having feedback provided by impedance elements Z3. Amplifier 28 amplifies the received signal RX′ signal arriving from line 26 to produce an output signal RX.
Hybrid circuit 21 includes a transformer 24 having a primary winding coupled to line 26, a secondary winding coupled to the output of amplifier 22 through impedance elements Z1, and another secondary winding coupled to the input of amplifier 28 through impedance elements Z2. Impedance elements Z1 match the nominal impedance of transmission line 26. For example, if the nominal line impedance is 100 Ohms, each impedance element Z1 should be 50 Ohms, assuming the turn ratio of the transformer windings is 1:1 between the transmit (TX) side and the line side of the transformer. Impedance elements Z2 present an impedance much higher than elements Z1 so that the impedance looking into hybrid circuit 21 from line 26 substantially matches the nominal line impedance 2·Z1. In inverting configuration, amplifier 28 acts as a low noise amplifier providing a gain of −Z3/Z2 to the signal arriving on line 26. A passive circuit H1 including series impedance elements H1Z residing between the output of line driver 22 and the input of amplifier 28. The reverse polarity of the differential signal flowing through the passive circuit H1 cancels the echo. If the nominal line impedance is, for example, 100 Ohms and the primary and secondaries of transformer 24 have identical numbers of turns, impedance elements Z1 can be 50 Ohm resistors and impedance element Z2 can be, for example, 1 KOhm. If the output of amplifier 22 is 1V, the voltage coupled to both the line side and the RX side of the transformer 24 will be approximately 0.5V. The echo at the output of amplifier 28 due to the coupling between the transformer secondaries will be 0.5V*Z3/1 KOhm. The signal voltage at the output of amplifier 28 due to the path through passive circuit H1 will be 1V*Z3/H1Z. To provide a good echo cancellation, H1Z should satisfy the following:0.5V*Z3/1 KOhm=1V*Z3/H1Z. This implies H1Z should be 2 KOhm. Since the line impedance for an ideal twist-pair transmission is a function of frequency, a simple series resistor implementation of H1 will not provide sufficient echo cancellation. However, a simple 2nd order RC network can provide sufficient echo cancellation. In general, if the line driver output is 1V and the line impedance is ZL, then the echo at the output of amplifier 28 due to the coupling between TX side and RX side of the transformer is approximately 1V*ZL/(2*Z1+ZL)*Z3/Z2. The signal at the output of amplifier 28 due to the path through circuit H1 will be 1V*Z3/H1Z. To achieve adequate echo cancellation, the single-end impedance H1Z of passive circuit H1 should satisfy1V*ZL/(2*Z1+ZL)*Z3/Z2=1V*Z3/H1Z. This impliesH1Z=Z2*(1+2*Z1/ZL).
The design of H1 becomes more difficult when transmission line 26 includes bridged taps and is therefore not an ideal twisted pair. Since the line impedance ZL is highly frequency dependent for a line 26 having bridged taps, it is not possible to achieve good echo cancellation using simple passive RC networks when line 26 has bridged taps. For a given loop length and bridged tap configuration, it is possible to replace the passive RC network H1 with a high order passive RLC network approximating the impedance Z2*(1+2*Z1/ZL). However, since inductors are expensive compared with other discrete circuit elements it can be preferable to use an active filter in lieu of an RLC network.
FIG. 3 illustrates a prior art transceiver 30 that is similar to transceiver 20 of FIG. 2 except that hybrid circuit 21 of transceiver 30 employs a 2nd order active filter circuit HA in place of passive circuit H1 of FIG. 2. FIG. 4 illustrates a prior art 2nd order active filter HA of the FIG. 3. In an integrated circuit, an active filter can be a low cost alternative to an expensive discrete RLC network because it can approximate any impedance, provided it does not contain right half plane poles that cause instability. However, an active filter introduces noise into a hybrid circuit, and the noise increases with the order of the filter. When the noise introduced by active filter HA is significant, it undermines the function of the low noise amplifier 28.
The unshielded twisted air transmission line 26 attenuates the received signal originating from the remote transmitter with, for example, a 40 dB loss and the receiver usually requires a few stages of amplification after amplifier 28 to boost the signal level to adequately compensate for the attenuation so that the signal is suitable for signal processing. The signal level sequentially increases from the first stage to the last stage, but each stage of amplification introduces added noise. The added noise is particularly detrimental in the earliest stage(s), since the signal levels are lowest. Therefore, it is important to use low noise amplifiers in the earliest stage(s) of amplification, however the circuit noise added by the introduction of active filter HA in hybrid circuit 30 can undermine the low noise function of amplifier 28. Thus to preserve signal integrity, active filter HA should be designed for low noise, but a low noise active filter is difficult to design, particularly when the order of the filter is high.
What is needed is a hybrid circuit architecture for use in connection with transmission lines having a variety of frequency-dependant impedances that does not require expensive RLC networks and that employs only easily designed, low noise, low order, active filters.


In an active hydrogen-containing B-side composition for reaction with a polyisocyanate-containing A-side composition to make a polyurethane or polyurethane/urea elastomer by reaction injected molding, the improvement which comprises a mold release composition which is the reaction product of a C.sub.12 -C.sub.36 fatty acid, a tertiary amine having at least one C.sub.12 -C.sub.18 alkyl substituent and a C.sub.2 -C.sub.21 reactive epoxide.

Reaction injection molding (RIM) is a versatile process by which elastomeric and thermoset parts can be fabricated. The RIM process involves high pressure impingement mixing of a polyisocyanate stream (A-side) and an active hydrogen containing, isocyanate-reactive stream (B-side) followed by immediate injection into the closed mold. The primary appeal of this process lies in its inherently high productivity. One factor which limits productivity, however, is the necessity to spray the molds with external mold release prior to each injection. This is a time consuming task and often has a negative environmental impact. This difficulty can be overcome by the incorporation of an internal release agent into the formulation via one of the two streams which significantly increases the number of molding cycles which can be accomplished between external mold release sprayings. While the internal mold release (IMR) approach is commercially applied, there remain significant shortcomings in the currently available internal mold release systems. The amine-solubilized metallic soaps, which are most commonly used in this application, have been implicated in reduced flowability and increased heat sags for the RIM elastomers in which they are used. Furthermore, the high melting points and limited solubilities of the metallic soaps makes them prone to precipitation in the RIM processing equipment, necessitating regular replacement of the piping.
Liquid IMR agents, particularly silicone fluids, have been investigated previously. Unfunctionalized polydimethylsiloxane fluids are unacceptable because they destabilize air nucleation on the B-side and cause painting problems. Carboxylic acid functionalized silicones have been described which alleviate some of the above limitations (U.S. Pat. No. 4,076,695), but cause serious reactivity problems with the polyurethane formation. Salts formed by the neutralization of tertiary amines with fatty acids have been disclosed (U.S. Pat. No. 4,098,731) as IMR for integral-skin urethane foams. Similarly, salts of primary amines are disclosed in U.S. Pat. No. 3,726,952. The equilibrium concentration of free carboxylic acids in such a salt of a relatively weak acid with a relatively weak basic amine is sufficient to cause reactivity problems similar to those observed in the acidic silicones.
U.S. Pat. No. 4,220,727 discloses aralkyl quaternary aninonium salts as release agents. All of the examples are chloride salts containing at least one "phenyl stearyl" group.
U.S. Pat. No. 4,040,992 discloses the use of N-hydroxyalkyl quaternary ammonium carbonylate salts as catalysts in the production of polyisocyanurates and polyurethanes. Among the exemplary preferred catalysts are N-hydroxypropyl trimethyl ammonium salts of carboxylic acids such as those of formic and acetic acids and of fatty acids such as hexanoic and octanoic acids and the like.

Hydroxyl containing quaternary ammonium salts of fatty acids as internal mold release compositions


The present disclosure relates to a coating composition for use in producing a coating on paper and other substrates comprising an aqueous suspension of a particulate pigment together with a binder, wherein the particulate pigment comprises a mixture of: a first pigment component comprising particulate ground calcium carbonate (GCC) having a particle size distribution (psd) steepness factor ranging from about 30 to about 45; and a second pigment component comprising particulate precipitated calcium carbonate (PCC) having a psd steepness factor ranging from about 55 to about 75. The particulate pigment may optionally further include a particulate kaolin clay.

Coated paper is used for a large range of products including packaging, board art paper, brochures, magazines, catalogues and leaflets. Such coated paper is required to give a range of properties, including brightness, opacity and sheet gloss, as well as printing performance.
Paper coating compositions are generally prepared by forming a fluid aqueous suspension of particulate pigment material together with a binder and other optional ingredients. The coating may conveniently be applied by means of a coating machine including a short dwell time coating head, which is a device in which a captive pond of coating composition under a slightly elevated pressure is held in contact with a moving paper web for a time in the range of from 0.0004 second to 0.01 second, before excess coating composition is removed by means of a metering blade. However, other types of coating apparatus may also be used for preparing coated paper. The coated paper is required to meet certain standards of surface gloss and smoothness. For example, the paper is generally required to have a gloss value of at least about 32, and up to about 70, in some cases up to about 90 TAPPI units, and a Parker Print Surf value in the range of from about 0.5 μm to about 1.6 μm.
It is known to use particulate calcium carbonate, either alone or in conjunction with other pigment material such as, for example, processed particulate kaolin clay, as a particulate pigment in paper coating compositions.
Particulate calcium carbonate can be obtained from natural sources or can be manufactured synthetically. Manufactured calcium carbonate is generally obtained by precipitation from aqueous solution. Precipitated calcium carbonate (PCC) is obtained in three different principal crystal forms: the vaterite form, which is thermodynamically unstable, the calcite form which is the most stable and is also the most abundant natural crystalline form, and the aragonite form which is metastable under normal ambient conditions of temperature and pressure, but converts to calcite at elevated temperatures.
The aragonite form typically crystallises as long, thin needles (acicular shape) having a typical length:diameter ratio of about 10:1, but the calcite form exists in several different shapes, of which the most commonly found are: the rhombohedral shape in which the crystals may be either aggregated or unaggregated; and the scalenodedral shape, in which the crystals are like double, two-pointed pyramids having a typical length:diameter ratio of about 4:1, and which are generally aggregated. All these forms of calcium carbonate can be prepared by carbonation of an aqueous lime-containing medium by suitable variation of the process conditions.
Calcium carbonate can be ground to obtain particulate ground calcium carbonate (GCC), by methods which are well known in the art.
Blends of PCC and GCC, and of different GCCs, for use in paper coating are known in the art.
For instance, U.S. Pat. No. 5,879,442, the disclosure of which is incorporated herein by reference, describes an aqueous slurry of calcium carbonate for use as a paper coating pigment, the slurry containing from 70 to 85% by weight of a combination of PCC particles and GCC particles in a weight proportion in the range 20:80 to 80:20, advantageously from 51:49 to 70:30. The calcium carbonate particles according to this patent have a median diameter in the range 0.2 to 2.0 μm, preferably from 0.3 to 1.5 μm. This patent, however, does not disclose the particle size distribution for the calcium carbonate particles.
Similarly, PCT Patent Application No. WO-A-01/53893, the disclosure of which is incorporated herein by reference, describes a printing paper having an image-receptive coating comprising a binder and a non-platy pigment. Examples are given (e.g. Examples A to D) of a non-platy pigment which comprises (out of 100 parts) 15 parts GCC, 75 to 79 parts PCC and 6 to 10 parts of a hollow sphere plastic pigment. This patent application discloses that, for glossy coated printing sheets, preferably about 90 to 95% of the calcium carbonate particles have an equivalent spherical diameter (esd) less than 2 μm and that, for matte coated printing sheets, preferably about 65% of the particles have an esd of less than 2 μm. The patent application also describes the calcium carbonate pigment exhibiting a relatively narrow particle size distribution, but it does not disclose what this is relative to. Further, details of the particle size distribution are not given.
The present invention comprises the discovery that improved properties can be obtained when paper is coated with a paper coating composition which includes a pigment comprising a blend of a selected particulate PCC and a selected particulate GCC or a blend of selected particulate GCCs. By using a blend of selected particulate PCC and GCC, a synergistic improvement to the opacity, brightness and print gloss of the paper has been discovered, when compared to paper in which the pigment in the coating is either one of the individual components of the blend.


A system and methodology for intelligent power management of wirelessly networked devices. The system provides for reliable wireless communication via a wireless power charging method and, a method to maintain power capacity of batteries in a wireless device. The batteries are charged via an RF harvesting unit embedded inside the wireless device. An intelligent wireless power charging system further comprises at least two batteries and at least two RF adaptor devices coupled to an AC power line. The first adaptor is set for data communication while the second adaptor is used to transmit the power. In addition, when a first battery is in use during active mode, the second battery is subjected to wireless charging.

Networking of small offices and homes are increasing in popularity. For example, in a home office, it is strongly desired to have the ability to inexpensively and reliably interconnect multiple network devices without having to install Ethernet or twisted pair backbone wiring. These network devices, for example, include personal computer, lap-top computers, printer, digital TV, set-top box, home appliances, etc. To achieve this, both wireless solutions and Internet on-power line solutions (e.g., according to the HomePlug® industry solution) have been considered as the physical layer backbone for such networking.
As known, the HomePlug® makes use of the existing in-home AC power wires for transmitting signal data at high speed. Conventional power line networks generally operate with data rates ranging from about 10 kbps to 350 kbps.
U.S. Pat. No. 4,815,106 issued to Propp, et al. entitled, "Power line Communication Apparatus", discloses a power line communication method via equalizer/coding scheme. A 350 kbps power line network system based on frequency modulation (FM) methods such as binary frequency shift keying (BFSK) can be achieved. In U.S. Pat. No. 6,243,413 issued to Beukema, et al., describes a modulation system used for a 1 Mbps power line communication channel.
Currently, all the wireless HomePlug® systems require a wireless device with an antenna and a wireless HomePlug® adaptor to facilitate wireless data communication between wireless devices and the network. However, wireless devices need power supply to keep them operational. Wireless devices, especially those portable ones, are mostly powered by using batteries. The batteries are periodically charged using a charging device typically plugged into a wall AC power outlet to obtain power there from.
In order to reduce wire congestion, wireless methods implementing a wireless device for charging batteries have been realized. These wireless charging methods include radio frequency interface, optical interface or, a magnetic interface to couple the battery pack to a wireless charging source. Several example of wireless charging battery systems include:
Currently, most RFID systems are passive and typically include a transmitter or transceiver device that is used to provide operational power (electromagnetic field, electric field, or magnetic field) to a receiver (tag) within a specified range. The tag in response to application of the transmitted operational power generates a signal that is received by a RFID system receiver (transceiver). The generated tag signal includes one or more unique identifiers for uniquely identifying the tag and object(s) associated therewith. In a passive RFID tag, no power storage and thus, no battery is needed. The passive power such as generated by an RFID transmit device however, can not be used to power existing wireless devices such as cell phone, portable computer, etc.
One way to charge a battery in a wireless manner is shown in US Patent application publication, 20060238365 by Vecchione; Elio; et al, titled "Short-range wireless power transmission and reception". It describes a method of short-range wireless power transmission and reception system. Power is transmitted from the electrical utility mains power supply to electrically powered appliances via electromagnetic radiation. The appliances are capable of receiving the transmitted power, converting it into electricity and storing it for subsequent use, as well as using it directly to power the appliances. This method is now implemented to charge battery of electric tooth brushes, however, it does not solve the wire congestion problem, since wire is still needed for the reception system.
US Patent application publication, 20070010295 by Greene; Charles E. et al, titled "Power transmission system, apparatus and method with communication", teaches a power transmission system with communication having a base station having a wireless power transmitter, a wireless data transmission component, and a first wireless data reception component. The system includes a remote station having a power harvester for converting the power from the power transmitter into direct current and a power storage component in communication with the power harvester for storing the direct current. Alternatively, the system includes a base station having a wireless power transmitter which transmits power at a frequency at which any sidebands are at or below a desired level, and a first wireless data communication component. The base station is used to transmit operational power and data to the remote station. Unlike RFID system, the proposed remote station is an active system meaning it contains power storage and has the ability to operate when the base station is not supplying the operational power. However, due to the lack of intelligent power charging system, a battery could be over charged or do not have enough capacity when the device is in usage. Additional issues are that no warning system is provided when device is placed out of charging range and there is no mechanism to guarantee a reliable and continuous operation, since battery charging will interrupt data communication operation.
US Patent application publication, 20060244573A1 by Wendler, Steve; titled, "Integration of antenna and solar charger for remote asset tracking", proposes an apparatus comprises a solar array configured to provide power to an asset tracking device and antennas configured to provide signals to the asset tracking device. The solar array comprises a bank of solar cells that are connected to the asset tracking device. The solar cells are configured to provide power to enable operation of the asset tracking device when external power is not available to the asset tracking device. Power from the solar array may be used to directly power the asset tracking device and/or charge a battery used by the asset tracking device. The antennas may include a Global Navigation Satellite System (GNSS) antenna as well as antennas that are used by a wireless transceiver to receive and transmit information to and from the asset tracking device, respectively.
These devices must be placed under the sun where solar energy is the only power source. It may be used in a green house, but the battery will be depleted at night or during cloudy day. It is not a reliable means to maintain power for devices such as cell phone or portable computers.
US Patent application publication, 20060251958A1 by Ayala, Adan; titled "Battery charge indicator", proposed a battery charge indicator for portable power tools, has indicator assembly to indicate state-of-charge of battery pack according to position of movable component moved by protrusion of cordless device and charger respectively. The battery charging level of a cordless tool is shown. When it is fully charged, the system can start charging the other battery. This tool is charged using a wired interface. There is no need of battery charging intelligence for such applications.
For a wireless power charging system, it is desirable to ensure that the batteries are maintained in full capacity so that there is no power outage during the utilization period of the wireless devices. It is further desirable that battery is not overcharged, that is when a full charge capacity is reached charging mechanism can be terminated. For HomePlug® applications, it is also necessary that wireless devices are located within a charging distance so that batteries of the devices can be effectively charged. Another critical aspect for such application is during utilization of the wireless devices, battery charging should not interrupt the data communication operation. There is a need of an intelligent charging system for HomePlug® system wherein batteries are automatically charged in a wireless mode to ensure uninterrupted wireless data communication.

Intelligent wireless power charging system

International Business Machines Corporation


Hard disk drive (HDD) including humidity sensor measuring interior and second humidity sensor measuring exterior with door actuator controlling door for mass transfer between interior and exterior based upon determination of whether or not to transfer. HDD may further include and use temperature sensors for interior and/or exterior to further control door. An embedded circuit and processor at least partly implementing these operations. External cover including door and door actuator, possibly second sensors. Manufacturing methods and these items as their products.

It is well known that the reliability of a hard disk drive is affected by both the temperature and humidity inside a hard disk drive. At high temperature and humidity, the slider's air bearing can lose lift, which decreases its flying height and increases the probability of contact between the read-write head and the rotating disk surface. Also, when the temperature decreases rapidly from a high temperature in a very humid situation, water vapor within the hard disk drive may condense on sensitive elements of the hard disk drive, such as the read-write head, slider and/or one or more of the disk surfaces.
The prior art shows several examples of three approaches to minimizing these effects. The first approach is to seal the hard disk drive, so that water vapor leaks in very slowly. A second approach is to include a water absorbent material or desiccant inside the hard disk drive to collect any incoming water vapor, which is thought to maintain internal humidity at a low level. These two approaches do increase the time it takes for the internal water vapor level to rise when such hard disk drives are exposed to environments with high water vapor pressure, where both the temperature and relative humidity are high.
However, there are problems with these approaches. Given enough time in an environment with high water vapor pressure, a hard disk drive using these approaches will be overcome by the abundance of water in its surroundings and what was useful before now makes things worse. For example, should the temperature inside such a hard disk drive rise, the desiccant will now release its stored water into the interior of the hard disk drive, causing the air bearing to lose lift, again, decreasing its flying height and increasing the probability of contact between the read-write head and the disk surface it accesses. Should the inside temperature decrease rapidly, the water vapor will tend to condense because the desiccant has a rate limit of absorption.
There is a third prior art approach, which is to make sure a hard disk drive is not sealed, but supports easy and rapid mass transfer between interior of the hard disk drive and its outside environment. This approach responds quickly to changes in external temperature and humidity, which is useful as the outside temperature and humidity decrease rapidly. However, such hard disk drives run into problems when exposed to high external temperatures and humidity, in that the interior soon has high temperature and humidity, causing the internal water vapor pressure to rise, the slider flying height to decrease and the probability of read-write head contact with a disk surface to increase.
What is needed are mechanisms and operating methods that can readily adapt to changes in the outside environment of a hard disk drive to minimize its interior water vapor pressure.

Method and apparatus intelligently adapting to environmental conditions inside and outside a hard disk drive


A ten-key section which is used to input identification information such as a password or ID number is disposed on the lower right side of or directly below a camera so that the hand of a to-be-recognized person who inputs identification information such as a password or ID number will not obstruct inputting of a face image

1. Field of the Invention
This invention relates to a face image recognition apparatus which recognizes the face image of a person for security management or the like and a passage control apparatus which controls the passage of a passer by use of the face image recognition apparatus.
2. Description of the Related Art
The face image recognition apparatus is used to recognize the face image of a person for security management or the like. An example of the conventional face image recognition apparatus is disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2001-5836, for example. In the face image recognition apparatus disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2001-5836, feature information items of the face images of registrants are previously registered in correspondence to identification information items in a dictionary. A to-be-recognized person who uses the face image recognition apparatus inputs his own identification information (such as an ID number). Then, the face image recognition apparatus specifies feature information corresponding to the identification information input by the to-be-recognized person in the dictionary and inputs the face image of the to-be-recognized person. After specifying the feature information corresponding to the identification information and inputting the face image of the to-be-recognized person, the face image recognition apparatus collates feature information extracted from the input face image with the feature information specified in the dictionary based on the identification information and performs the recognition process for the face image of the to-be-recognized person.
Thus, in the conventional face image recognition apparatus, a method for permitting the to-be-recognized person to input his own identification information and specify registration information (feature information) registered in the dictionary is used. For example, in the conventional face image recognition apparatus disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2001-5836, identification information of the to-be-recognized person is input by use of a key input section such as a keyboard or card reader. Further, in the conventional face image recognition apparatus, registration information is specified in the dictionary and the face image of the to-be-recognized person is input by use of the image input section after input of identification information by the to-be-recognized person is completed.


The retinoids, in particular the anti-AP-1 retinoids, effectively inhibit the expression of VEGF, and thus are useful for the therapeutic treatment of disease states manifesting an overexpression of VEGF.

1. Technical Field of the Invention
The present invention relates to inhibiting the expression of VEGF by administration of retinoids, in particular anti-AP-1 (Activator Protein-1) retinoids. This invention also relates to the retinoid treatment of disease states manifesting an overexpression of VEGF, in particular psoriasis, Kaposi's syndrome, bullous dermatoses, tumors, metastases, angiomas, eczema, urticaria, cutaneous hypersensitivity type IV, rheumatoid arthritis, and contact allergies.
2. Description of the Prior Art
VEGF, or "Vascular Endothelial Growth Factor," is a 34-36 kDa homodimeric glycoprotein whose sequence reflects an approximately 20% identity with the A and B chains of PDGF (Tischer et al., J. Biol. Chem., 266, 11947-11954 (1991)). The additional DNA sequence of VEGF codes for a signal peptide enabling it to be secreted in opposition to FGF (Fibroblast Growth Factor), which does not contain such a sequence in the structure of its gene. Because the major production sites and the action sites are different, VEGF acts principally in a paracrine mode. The presence of VEGF has been discovered in both numerous tumors and healthy tissue (D. L. Senger et al., Cancer Metastasis Rev., 12, 303-324 (1993)).
In healthy skin, the expression of VEGF may be increased following an injury (L. F. Brown et al., J. Exp. Med., 176, 1375-1379 (1992)). The overexpression of VEGF has also been determined in numerous skin diseases associated with vascular hyperproliferation and/or to vascular changes, as in psoriasis patches (M. Detmar et al., J. Exp. Med., 180, 1141-1146 (1994)), in Kaposi's syndrome (K. Weindel et al., Biochem. Biophys. Res. Commun., 183, 1167-74 (1992)), and in bullous dermatoses (L. F. Brown et al., J. Invest. Dermatol., 104, 744-749 (1995)).
It is widely known that all-trans retinoic acid affects cell differentiation and/or proliferation by interacting with nuclear receptors, or sRAR (Retinoic Acid Receptors) contained in the cell nucleus. 9-cis retinoic acid also interacts with Retinoic X Receptors (sRXR). Numerous synthetic analogs exhibit biological activity similar to that of all-trans retinoic acid or 9-cis-retinoic acid. These compounds are generally designated "retinoids." Included among the retinoids are, more specifically, RAR agonists, which interact with the sRAR receptors; these include etretinate and adapalene. To date, there are three known subclasses of RAR receptors, termed .alpha.-RAR, .beta.-RAR, and .gamma.-RAR. After fixation of a ligand (i.e., all-trans retinoic acid), these receptors interact with the region promoting genes regulated by retinoic acid in specific response elements (RARE).
Certain analogs may become fixed and may activate a subclass of RAR receptor (.alpha., .beta., or .gamma.). Finally, other analogs elicit no specific selective activity with respect to these various receptors. In this regard, for example, all-trans retinoic acid activates the sRAR (sRAR specific agonist ligand) belonging to all subclasses.
Numerous dermatological diseases and/or disorders may entail poor regulation of the sRAR receptors. These diseases and/or disorders most often exhibit an inflammatory, allergic, and/or immunological component. Retinoic acid, and, retinoids such as etretinate and adapalene, are drug species used to treat acne. Retinoic acid has also been described as a therapeutic active agent for treating the signs of skin aging, whether chronological or photoinduced (U.S. Pat. No. 4,888,342).
Certain retinoids have been described as effective for regulating the expression of genes, such as keratins (M. Tomic-Canic et al., J. Biol. Chem., 271, 1416-1423 (1996)) or for altering PDGF activity in psoriatic fibroblasts (F. Raynaud et al., J. Invest. Dermatol., 96, 111-115 (1991)). And certain retinoids have also been demonstrated to exhibit anti-AP-1 activity, namely, they inhibit AP-1 activity (WO-95/33,745). To date, no effect elicited by retinoids on VEGF expression has been reported in the literature (see, for example, Harada et al., J. Clin. Invest., 93, 2490-2496 (1993)).

Retinoid inhibition of expression of VEGF

Centre International de Recherches Dermatologiques


This invention relates to a novel gauge lighting structure, mainly comprising the gauge panel, the lighting guide element and the lighting supply element. The gauge panel is very broadly used on the instrument cluster of the transportation vehicles. The gauge panel is an empty round housing with a glass pane mounted on the top for seeing through the signs or the record on the panel. The lighting guide element is a curve tube made of lighting sensitive material. The lighting supply element supplies the lighting from one end or two ends of the lighting guide tube. The lighting guide tube will absorb and transmit the lighting coming from the lighting supply and illuminate the inside of the gauge panel. The luminance of the lighting supply element is well controlled to regulate the sensitive lighting in the light guide tube to obtain clear signal signs and decorative blinking.

1. Field of the Invention
This invention concerns the a gauge lighting structure, an improvement for used on the gauges mounted on the instrument panel of vehicles to display the clear sign in the gauge and to render the blinking decoration.
2. Description of the Related Art
On the traditional instrument cluster of the vehicle, the handle of the gauge is usually driven by the servo motor mounted at the back center or one side of the gauge, and the dials or figures; it shows the working conditions of the vehicle. Such as speedometer, RPM gauge, fuel level gauge, etc. These mechanical gauges require other lighting supply to display what the gauge shows in the darkness. It is not easy to assemble, not good for viewing in the darkness, the traditional instrument panel uses outside lighting supply, but not sufficiently to display various messages and figure contained.
For this reason, the inventor has worked hard for years to come up with a novel gauge lighting structure in an attempt to simplify the mechanical gauge in structure, fabrication and assembly and ensure a better performance.


A method for furnishing a therapeutic-agent-containing medical device is provided. The method comprises: (a) providing a reactive layer comprising a cross-linking agent on a medical device surface; and (b) subsequently applying a polymer-containing layer, which comprises a polymer and a therapeutic agent, over the reactive layer. The cross-linking agent interacts with the polymer to form a cross-linked polymeric region that comprises the therapeutic agent. Moreover, in certain embodiments, the polymer-containing layer does not comprise the cross-linking agent at the time the polymer-containing layer is applied over the reactive layer. Examples of medical devices include implantable or insertable medical devices, for example, catheters, balloon, cerebral aneurysm filler coils, arterio-venous shunts and stents.

1. Field of the Invention
The present invention relates to medical devices with polymeric coatings and more particularly to medical devices having polymer coatings that release therapeutic agent.
2. Brief Description of the Background Art
Numerous medical devices have been developed for the delivery of therapeutic agents to the body. For example, in accordance with some delivery strategies, a therapeutic agent is provided within a polymeric carrier layer that is associated with a medical device. Once the medical device is placed at the desired location within a patient, the therapeutic agent is released from the medical device. The desired release profile for the therapeutic agent is dependent upon the particular treatment at hand, including the specific condition being treated/prevented, the specific therapeutic agent selected, the specific site of administration, and so forth.
Therapeutic agents are frequently handled in aqueous solutions. Unfortunately, directly coating the surface of a metallic medical device, for example, a stent, with an aqueous solution can be problematic, because metals are typically quite hydrophobic. As a result, the cohesive forces within the aqueous solution tend to pool the solution on the medical device surface, rather than wetting the entire surface. Low coating retention, frequently involving very expensive therapeutic agents, is associated with this phenomenon.

This patent is subject to a terminal disclaimer.

Processes for producing polymer coatings for release of therapeutic agent


An optical phonograph cartridge includes an optical vibration sensor that operatively couples to a stylus/cantilever to convert, to optical signals, mechanical vibrations representative of the music encoded in the groove of a vinyl record. The optical vibration sensor includes a photonic integrated circuit includes an input waveguide network for conveying light and an output waveguide network for conveying modulated light, wherein the modulated light is generated by a screen that is attached to the cantilever and is disposed between the input and output waveguide networks.

The vinyl long-playing ("LP") record was introduced in 1948 and remained the physical medium of choice for recorded music for about 35 years. But by the early 1980s, a new optical recording and playback technology/medium known as the compact disc or "CD" was commercially introduced. In addition to promising "perfect sound forever," the CD had a high convenience factor, such as requiring far less care than vinyl, no need to flip the record from side A to side B, and no annoying pops and tics so familiar to vinyl-music listeners. There was a very rapid and broad acceptance of the CD by the music-buying public. By 2002, CD sales accounted for 95.5% of recorded music revenues, and the vinyl LP was on life support.
But to the surprise of many within the industry, within another 10 years, this trend began reversing itself. By 2018, CD sales were declining and the sale of vinyl was increasing, the former 3× faster than the latter. A number of reasons have been proposed for this phenomenon, including a trendiness factor, particularly with younger listeners, and a belief held by some, particularly audiophiles, that listening to vinyl is a more immersive and ultimately more enjoyable experience than listening to a CD. For whatever the reasons, 40 years after the commercial introduction of CDs and long after the LP was pronounced dead, a vinyl revival is underway.
Given this vinyl resurgence, long-dormant record pressing facilities have begun to reopen, new pressing plants are being built, and audio equipment manufacturers are producing new and improved versions of the equipment involved in the vinyl-record playback chain. A brief discussion of such equipment follows, including turntables, tonearms, cartridges, and the phono stage.
Music Encoding and Playback.
Information—typically music—is encoded in the grooves (actually, it is single, long groove) of a vinyl LP. At a microscopic scale, the walls of the grooves are rippled. These ripples in the groove walls can be considered a fingerprint of the music soundwave at any point in time. To correctly reproduce the encoded music, the music signal must be extracted from the groove, and at an appropriate rate. To accomplish this, the LP is rotated, which is the function of the turntable. The turntable includes a circular platter on which an LP is placed. The platter is driven by a motor, which causes the platter and LP to rotate at a very precise speed, typically 33⅓ rpm (but also 45 rpm, and, for some much older vinyl LPs, 78 rpm).
The phonograph cartridge is the device that extracts the audio information stored in the groove of the LP. The point of contact between the LP and the cartridge is a very small stylus or needle that extends from the body of the cartridge into the grooves of the LP. The stylus wiggles or vibrates as dictated by the ripples in the groove of the LP. Assuming the LP and cartridge are stereo (as opposed to mono), the needle's vibratory motion is converted to two electrical signals corresponding to a left music channel and right music channel by other elements of the cartridge, as discussed further below. These signals are an electrical representation of the stereo music encoded on an LP.
The cartridge is attached to one end of a tone arm, which supports the cartridge as its stylus rides in the groove of the LP. The other end of the tone arm is supported at a pivot point, about which the tone arm is free to rotate. In this fashion, as the record spins, the stylus follows the groove, beginning at the outer circumference of the LP (the beginning of the groove) and moving inward towards the center of the LP (the end of the groove), as facilitated by the pivoted tone arm. The turntable, tone arm, and cartridge are often collectively referred to as a record player.
The electrical signals generated by the phono cartridge are carried by wires through the tone arm to a phono stage. The phono stage has two primary functions: equalization and amplification.
Equalization is required due to the physics of vinyl music reproduction. Physical ripples/modulations in the groove must model the sound being recorded. Lower frequencies (longer wavelengths) require more physical space than higher frequencies (shorter wavelengths). Since space is at a premium on a vinyl LP, during the record-cutting process, the music is equalized, wherein the lower frequencies are deemphasized and higher frequencies are boosted. For the music to be correctly reproduced, the process must be reversed during playback, wherein the lower frequencies are boosted and the higher frequencies are de-emphasized. Furthermore, due to non-linearities that arise by virtue of the electromagnetic cartridge itself, further correction or equalization is required to obtain a relatively flat frequency response. Both of these corrections are performed in accordance with a standard curve developed by the Recording Industry Association of America, and known as RIAA equalization.
The second function—amplification—is required due to the limitations of the cartridge. The electrical (music) signals generated by a cartridge can be as low as about 0.2 millivolts, depending on cartridge type. By comparison, the output voltage of a CD is specified to be 2 volts, which is orders of magnitude greater than that of the cartridge's output voltage. The output signal of a cartridge must therefore be amplified significantly before it can be further processed, such as in a preamplifier, or in the pre-amplification stage of an integrated amplifier or of a stereo receiver.
Cartridge Design.
FIGS. 1 and 2 depict two widely used prior-art cartridge designs, the "moving magnet" (MM) cartridge and the "moving coil" (MC) cartridge, respectively. Both cartridges operate in accordance with the same underlying principle, which is using movement to induce current in the presence of magnetic fields. More particularly, in a MM cartridge, one or more magnet(s) move, inducing current in fixed coils. In a MC cartridge, the magnet(s) are stationary, and the coil(s) moves.
FIG. 1 depicts the salient elements of MM cartridge 100, including cantilever 102, stylus 104, damper 106, magnet(s) 108, suspension 110, and coils 112A and 112B, arranged as depicted. FIG. 2 depicts the salient elements of MC cartridge 200, including cantilever 202, stylus 104, damper 106, magnet(s) 208, suspension 210, and coils 212A and 212B, arranged as depicted.
In both MM cartridge 100 and MC cartridge 200, stylus 104 is the point of contact with the surface of the vinyl LP. When an LP is rotated, stylus 104 tracks the ripples in the groove. Stylus 104 is made of a very hard material, such as industrial diamond or other gemstones.
With continued reference to both FIGS. 1 and 2, stylus 104 is rigidly attached to cantilever 102, 202. The cantilever thus moves in concert with stylus 104, transmitting vibrations (which include horizontal and vertical components) to electromagnetic generator 114. Cantilever 102, 202 is typically made of boron or aluminum, but in some upscale cartridges, may be made of gemstones, bamboo, or other relatively exotic materials.
Cantilever 102, 202 is received by suspension 110, 210. Damper 106 surrounds the cantilever where it couples to the suspension; the damper facilitates vibratory movement of cantilever 102, 202. Coupled to a tonearm (not depicted) and rigid parts of the cartridge (e.g., suspension 110, 210, etc.), the moving parts of the cartridge (i.e., stylus and cantilever) are provided with a stationary platform for tracking the LP groove with precision.
In MM cartridge 100, one or more magnets 108 are disposed at the opposite end of cantilever 102 from stylus 104. In this embodiment, a length of wire winds around suspension 110 at two (and sometimes four) locations comprising coils 112A and 112B, such that magnet 108 resides between the two coils. In MM cartridge 100, magnet(s) 108 and coils 112 define electromagnetic generator 114. As the stylus and cantilever vibrate as dictated by the music signal encoded in the groove, a current is generated in each coil 112. These electrical signals are a representation of the Left and Right music channels (for a stereo LP).
In MC cartridge 200, independent lengths of wire wind around cantilever 202 forming coils 212A and 212B at the opposite end of the cantilever from stylus 104. In this embodiment, magnet(s) 208 is supported by suspension 210 on one side of coil 212. In MC cartridge 200, magnet(s) 208 and coils 212A and 212B define electromagnetic generator 114. (Although not clear from the 2D representation depicted in FIG. 2, the coils are actually between the North and South poles of magnet(s) 208.)
Coils 112A and 112B of MM cartridge 100 each have many more windings than coils 212A and 212B of MC cartridge 200. MM cartridge 100 therefore produces a higher output voltage than MC cartridge 200. Consequently, the output signal of MC cartridge 200 requires an additional amplification stage relative to MM cartridge 100. Since coils 212A and 212B on the cantilever of the MC cartridge are lighter than magnet(s) 108 on the cantilever of the MM cartridge, the MC cartridge has the lower effective tip mass. This provides the MC cartridge with some significant performance advantages relative to the MM cartridge, including wider frequency response, improved transient response, and more detailed reproduction, particularly for signals that are low in level, which the heavier tip mass of the MM cartridge may not resolve.
Encoding.
As previously mentioned, modulations in the groove of the vinyl LP encode the music signal. In further detail, a vinyl LP has a single (very long) groove, with each side of the groove oriented at a 45-degree angle to the plane of the surface of the LP. This results in combined vertical and horizontal motion of the stylus. These two types of motion are captured independently by the stylus, and converted to electrical signals via the action of electromagnetic generator 114.
Cartridge Innovations.
Ironically, one of the more recent innovations in phono cartridge design has been the introduction, by one manufacturer, of an "optical cartridge." Although first developed over 40 years ago, the optical cartridge is now practical because of developments in LED technology. FIG. 3A depicts the salient elements of optical cartridge 300, including stylus 104, cantilever 302, LED light source 320, screen 324, and two photodetectors 330A/B, arranged as depicted.
As in the conventional MM and MC cartridges previously discussed, stylus 104 is rigidly attached at the end of cantilever 302. However, unlike MM and MC cartridges, optical cartridge 300 has neither magnet(s) nor coil(s) coupled to the cantilever. Rather, in optical cartridge 300, screen 324 is attached to the cantilever. The screen is opaque to light 322 emitted towards it by LED 320. The LED is supported by other portions (not depicted) of the cartridge; it is not coupled to cantilever 302. Based on the screen's position, as a function of the movement of the stylus and cantilever, some portion of light 322 emitted from LED 320 is blocked.
Screen 324 is positioned between LED 320 and photodetectors 330A and 330B, which are contained in housing 326. The housing is supported by non-depicted portions of optical cartridge 300. Housing 326 incorporates two openings 328A and 328B. Light 322 from LED 320 not blocked by screen 324 enters through one or both of these openings and is detected by respective photodetectors 330A and 330B therein. The opening 328A or 328B, or both, through which light enters housing 326, and the amount of light entering through these openings, is a function of the position of screen 324 at any instant.
As previously discussed, and as depicted in FIG. 3B, a stylus moves "upwardly left/downwardly right" when tracking the right wall of the groove of an LP and "upwardly right/downwardly left" when tracking the left wall of the groove of an LP. This causes screen 324 to move in the same fashion, as depicted via the bi-directional arrows in FIG. 3C. Such movement results in some or all of light 322 from entering opening 328A and some or all of light 322 from entering opening 328B (although light will enter at least one of openings 328A or 328B).
Thus, there will be a change in the intensity of light 322 entering housing 326 and detected by photodetectors 330A and 330B. The light detected by each photodetector corresponds to, or is otherwise capable of being correlated to, one of the two music channels. The photodetectors generate electrical signals in response to the light intensity they each receive in conventional fashion. Those electrical signals are then output from the cartridge to wires running through the tonearm.
It is notable that optical cartridge 300 extracts information from the groove of a vinyl LP in the same manner as that of conventional MM and MC cartridges; that is, via a stylus, such as stylus 104. In operation, stylus 104 rides in the LP's groove, vibrating in accordance with the encoded musical signal. As in conventional phono cartridges, cantilever 302 moves in concert with stylus 104. Since screen 324 is rigidly coupled to cantilever 302, its movement follows that of the cantilever and stylus. However, rather than immediately converting the mechanical movement of the stylus/cantilever to electrical signals, the combination of LED 320, screen 324, and openings 328A and 328 first convert such mechanical movement to optical signals. These optical signals are then immediately converted back to electrical signals via photodetectors 330A and 330B within the confines of optical cartridge 300.
Optical cartridge 300 cannot use a conventional phono stage, such as previously discussed. Rather, the optical cartridge requires its own unique phono stage, which functions somewhat differently than a conventional phono stage. In particular, unlike a conventional phono stage, the phono stage for optical cartridge 300 provides a voltage to the cartridge to drive LED 320.
Moreover, the standard RIAA equalization curve, as required for MM and MC cartridges, is unsuitable for use with optical cartridge 300. This is because whereas the response (i.e., output) of an MM or MC cartridge is non-linear with the frequency of the music signal ("velocity dependent"), the response of optical cartridge 320 to frequency is linear. That is, the MM/MC cartridge has a velocity proportional output wherein optical cartridge 320 has an amplitude proportional output. Consequently, significantly less processing of the signals from optical cartridge 320 is required.
The electrical signals generated by photodetectors 330A and 330B have a higher output voltage than the voltages generated by a MM or MC cartridge. As a consequence, although electrical signals transit the tone arm whether MM cartridge 100, MC cartridge 200, or optical cartridge 300 is used, to the extent any electrical noise is picked up during such transit, use of the optical cartridge will yield a higher signal-to-noise ratio than is possible for the MM or MC cartridges.
Finally, since screen 324 on the cantilever of optical cartridge 300 is lighter than the magnet(s) or coil(s) on the cantilever of a MM or MC cartridge, the optical cartridge has a lower effective tip mass. The benefits of such lower effective tip mass have been discussed in the context of the comparison between the MM and MC cartridges.


A transforming device includes: a body; a movable element movable between a storage position and a separate position, wherein the movable element is accommodated in the body when the movable element is disposed at the storage position, and wherein the movable element is separated from the body when the movable element is disposed at the separate position; a pushing element for pushing the movable element from the storage position to the separate position; and a pair of magnets. One magnet is disposed in the body, and the other magnet is disposed in the movable element. The pair of magnets generates auxiliary force for pushing the movable element from the storage position to the separate position.

Recently, in an in-vehicle device such as a vehicle navigation device and a vehicle audio device, the weight of a display as a transforming element becomes large since the dimensions of the display becomes large.
In JP-A-2005-47483 corresponding to US Patent Application Publication No. 2005-0144819, the in-vehicle device includes an auxiliary force generating element for assisting displacement of the display. The auxiliary force generating element is composed of a spring, an ejecting lever, a support member and the like. The ejecting lever receives elastic force of the spring so that the ejecting lever ejects the upper side of the display. The support member supports the ejecting lever.
When the display moves from a storage position to a separate position, the display is ejected forward with using a slide element, which is connected to a lower side of the display. At this time, the auxiliary force generated by the auxiliary force generating element is applied to the upper side of the display.
However, the auxiliary force generating element includes many members such as the spring, the ejecting lever and the support member. Assembling process of the auxiliary force generating element and mounting process of the auxiliary force generating element in the display are complicated so that manufacturing time of the display becomes longer.
Since the weight of the display is large, the auxiliary force generating element needs to generate large auxiliary force so that the display is smoothly moved, i.e., displaced. However, it is difficult to mount the spring capable of generating the large auxiliary force in a limited space of the in-vehicle device.


A generally cylindrical expansible shaft includes an outer profile, and a generally cylindrical inner body having a longitudinal axis and at least one first coupling element. At least two semi-circular leaf elements may be movably coupled to the first coupling element of the inner body by means of at least one second coupling element. The leaf elements may together substantially form the outer profile of the generally cylindrical expansible shaft. At least one thrusting element may be operatively disposed between the leaf elements and the inner body to move the leaf elements radially outwards relative to the longitudinal axis to increase an outer diameter of the shaft when in a first configuration, and allow the leaf elements to move radially inwards relative to the longitudinal axis to decrease the outer diameter of the shaft when in a second configuration.

a. Field of Invention
The invention relates generally to an expanding shaft, and, more particularly to an expanding shaft of the type which carries tubular supports on which strips of plastic, aluminum or paper films are wound or from which the strips are unwound.
b. Description of Related Art
During the manufacture of plastic, aluminum, paper or other sheet products, the sheet material is typically wound onto, or unwound from, a tubular core supported by a diametrically expansible shaft which is inserted into the core and expanded to grip the core frictionally. Such shafts are typically used when slitting a wide web of material into discrete widths and rewinding the material on the core. Conventional expansible roll core shafts typically employ a large number of relatively small, separate core-engaging elements expansible by a common internal air-expandable bladder, or by a plurality of individually controllable air-expandable bladders.
Of known varieties of expansible shafts, as disclosed in U.S. Pat. No. 3,904,144, the disclosure of which is incorporated herein by reference, one type of shaft includes straight, parallel slots cut longitudinally in the periphery thereof. The slots include straight, separate, air-expandable, resilient bladders overlain by respective straight core-contacting elements which extend throughout the length of the shaft. One key drawback in such a shaft is in the overall ability to evenly load delicate cores to eliminate core distortion or damage, and the overall excessive weight of such shafts, which requires the implementation of special handling procedures and methods, and thus increases the overall manufacturing and operational costs for such shafts.
Other known varieties of expansible shafts include the shaft designs disclosed in U.S. Pat. Nos. 5,597,134 and 5,746,386, the respective disclosures of which are incorporated herein by reference.
The expansible shafts disclosed in the '134 and '386 patents disclose the use of mobile means mounted for radial movement within slots in the expanding shaft. Core stops are adjustably mounted for axial movement longitudinally of at least one of the mobile means to vary the spacing of the core stops longitudinally of the shaft as desired. Locking means is provided for locking the core stops in position axially of the mobile means and the shaft. With the arrangement as shown in the '134 and '386 patents, the longitudinal position of the core stops relative to the shaft can be adjusted while the shaft is mounted on a slitter-rewinder machine. However, due to the weight of the shaft and associated components, it generally takes a significant amount of labor and down time of the machine while such changes are made.
While the expansible shaft disclosed in U.S. Pat. No. 6,196,494, which is owned by the assignee herein and the disclosure of which is incorporated herein by reference, provided significant improvement in the construction of an expansible shaft over the shafts disclosed in the '134 and '386 patents so as to permit the slit widths on a slitter-rewinder machine to be changed in a minimum amount of time, there remains a need for an improved expansible shaft having a reduced overall weight for further facilitating the overall manufacturing and operational costs thereof. There also remains a need for an improved expansible shaft which enables the application of higher torsional loads, and improved core loading for eliminating core distortion or damage, and an expansible shaft which is easier to assemble and disassemble, which includes a limited number of required components for ease of operability as well as for increased reliability and robustness of design, and which is economically feasible to manufacture.

Ultra-light pneumatic leaf expanding shaft


In a planetary gear arrangement with a planetary gear which includes a rotating part and a non-rotating part, and with a sensor module for sensing properties of the planetary gear, the sensor module includes a sensor as well as a first sending/receiving unit and a second sending/receiving unit, wherein the sensor and the first sending/receiving unit are coupled and arranged at the rotating part, and wherein the second sending/receiving unit is arranged at the non-rotating part, wherein the first sending/receiving unit and the second sending/receiving unit are configured for being inductively coupled, wherein the first sending/receiving unit includes an energy storage, wherein the energy storage is configured for being charged during each turn of the rotating part for powering the sensor via the first sending/receiving unit in order to perform measurements.

The present invention relates to a planetary gear arrangement with a planetary gear and sensor module.
In gears, such as planetary gears, it can be necessary to monitor different conditions of the gear during operation. For this purpose, a sensor can be provided in the gear. As this sensor has to be powered, the sensor is often arranged in the non-rotating part of the gear since at this position, an energy supply via cable is easily possible. However, if the sensor is arranged in the rotating part of the gear, an energy supply via battery is necessary for this purpose, wherein the battery will be arranged in the rotating part for enabling a connection to the sensor. With such a battery, it is only possible to provide energy for a limited time, namely until the battery is discharged.
For example, from DE 20 2016 106 888 U1, a device for condition monitoring of a gear element, in particular a gear of a wind turbine, is known. Thereby, the device comprises, in addition to a sensor element, also an energy supply unit which supplies electrical energy to the sensor element. The energy supply unit may be for example a nanogenerator for generating electrical energy, an energy storage or a wireless energy transmission. The transmission of the sensed condition values can be wirelessly carried out. The sensor element is either directly integrated at a source of the condition values or at least indirectly connected to the source of the condition values via a couple medium. This leads to an improvement of the signal quality of the condition values to be sensed.
It is thus desirable to provide an improved planetary gear arrangement in which a sensor may be arranged in the rotating part of the planetary gear and may be easily powered.
According to an aspect of the present invention, a planetary gear arrangement comprises a planetary gear with a rotating part and a non-rotating part and a sensor module for sensing properties of the planetary gear. For this purpose, the sensor module comprises a sensor as well as a first sending/receiving unit and a second sending/receiving unit. The sensor and the first sending/receiving unit are arranged in the rotating part. Hereby, properties of the planetary gear may be sensed directly at the rotating part. For powering the sensor and for retrieving the sensed properties from the sensor, the sensor is coupled to the first sending/receiving unit. This connection may be made by means of a wired coupling.
The second sending/receiving unit is arranged at the non-rotating part. For being able to power the sensor, the first sending/receiving unit and the second sending/receiving unit configured to be inductively coupled during a rotation of the rotating part. During a rotation of the rotating part, the first sending/receiving unit is passed by the second sending/receiving unit in regular intervals, wherein an inductive coupling takes place when the two sending/receiving units are facing each other. Hereby, an energy transmission takes place from the second sending/receiving unit to the first sending/receiving unit. This transmission occurs every time, when the two sending/receiving units are inductively coupled, i.e. when they are passing by each other. This occurs once per rotation round.
Furthermore, the first sending/receiving, unit may comprise an energy storage. The energy storage may be for example a capacitor. The energy storage may be charged during each turn of the rotating part, i.e. every time, when there is an inductive coupling between the two sending/receiving units. Thereby, it can be achieved that the sensor has sufficient energy at its disposal via the first sending/receiving unit for carrying out measurements. However, the energy storage only has to be large enough that it can store enough energy for ensuring an energy supply of the sensor until a recharging of the energy storage may be carried out. For example, enough energy may be stored by means of the energy storage for supplying energy to the sensor also if no turn of the rotating part takes place or if there is no inductive coupling during the turn. The energy storage may thus serve as energy buffer.
It is also possible that the energy storage first needs to be charged until it has a sufficient capacity in order to be able to power the sensor.
In contrast to a battery which shall supply energy to the sensor, as it has been the case in systems known until now, the energy storage as herein provided may be configured very small as it has not to ensure the complete energy supply. Instead, the energy is provided by means of the inductive coupling, wherein the energy storage only serves as buffer.
The planetary gear arrangement may comprise multiple sensor modules. In particular, the planetary gear arrangement, which comprises multiple planets, may comprise one sensor module per planet. Each sensor module may comprise multiple sensors. For example, one sensor module may comprise a vibration sensor, a temperature sensor and/or an accelerometer. The sensor and the first sending/receiving unit may be configured as one integral unit.
The sensor module may comprise a computing unit which is arranged in the rotating part. The computing unit may be used for performing a preprocessing of the sensed properties. Thereby, data, which are already preprocessed, may be transmitted to the second sending/receiving unit, thereby reducing the amount of data which needs to be transmitted.
According torn embodiment, the sensor is configured for transmitting sensed properties of the planetary gear via the first sending/receiving unit to the second sending/receiving unit. This transmission may be carried out using the inductive coupling between the sending/receiving units. At the same time, the inductive coupling between the two sending/receiving units is used for supplying energy to the first sending/receiving unit.
Alternatively, the transmission of the sensed properties may be carried out via a radiocommunication. In this case, the first and the second sending/receiving unit additionally comprise a radio transmitting element, for example an RFID element. The transmission may be bidirectionally configured so that information from the second sending/receiving unit, for example from an external control unit, may be transmitted to the sensor. This information may serve for initiating the sensing of properties by the sensor.
According to an embodiment, the second sending/receiving unit comprises a transmitting coil and the first sending/receiving unit comprises a receiving coil. Energy may be easily transmitted to the receiving coil by means of the transmitting coil via an inductive coupling, i.e. without a direct connection.
According to an embodiment, the energy may be supplied via the second sending/receiving unit from an external energy supply being connected to the second sending/receiving unit. This connection can be made for example via a cable by means of which the second sending/receiving unit may be connected to a current/voltage source. With an inductive coupling between the transmitting and the receiving coil, the energy is transmitted from the external energy supply via the transmitting coil to the receiving coil.
Thus, the inductive coupling between the two sending/receiving units serves for transmitting energy as well as for transmitting data. Thus, the first sending/receiving unit and the sensor, which is provided for sensing properties of the planetary gear, may be easily arranged in the rotating, part of the planetary gear, while the energy supply, which is carried out by the second sending/receiving unit, may be arranged in the non-rotating part.
As by this arrangement, there is no need to provide a battery in the rotating part of the planetary gear, space may be saved within the gear. By means of the inductive coupling, the sensor, however, may be easily powered. Furthermore, the planetary gear arrangement will be more robust by omitting of a battery since the planetary gear arrangement is less prone to failures due to the battery. Thereby, the lifetime of the whole arrangement will be increased.
The second sending/receiving unit can be connected to a processing unit. In one embodiment, this connection may be carried out via the same cable as the connection to the external energy supply. The processing unit may be configured to receive and to process the properties of the planetary gear sensed by the sensor or to transmit the properties to further units. The processing unit may be configured as gateway which provides a connection between the sensor module and external systems as a hardware and/or a software component. This gateway may perform different functions, such as receiving and transmitting of data to/from the sensor (via the first and second sending/receiving unit) and powering the second sending/receiving unit. As the gateway may be arranged outside of the gear, there is sufficient space for powering the gateway via a standard energy supply.
According to an embodiment, the energy storage may be arranged in the rotating part of the planetary gear, for example a shaft, axis or planetary pin of the planetary gear. Thereby, the energy storage may rotate together with the first sending/receiving unit.
Further advantages and preferred embodiments are disclosed in the description, the figures and the claims. In particular, the combinations of features being disclosed in the description and the figures are solely exemplary so that features may be present also individually or combined otherwise.


A pair of eyeglasses includes an eyeglass frame and a lens unit mounted detachably on the eyeglass frame. The eyeglass frame includes a curved front frame with two downwardly projecting end portions, and two bows. The curved front frame has an engagement groove formed therein, and a retained portion disposed at the middle section of the curved front frame. The engagement groove has two end portions respectively extending into the front surfaces of the downwardly projecting end portions of the curved front frame. The lens unit includes two lenses and a plastic lens rim mounted securely on the lenses. The lens rim has a rib projecting upward from the upper end portion thereof so as to engage the engagement groove. The rib has two lugs projecting respectively and outwardly from two ends thereof and being inserted into the end portions of the engagement groove. A hook is fixed on the lens rim and has a retaining space formed therein so as to retain the retained portion of the curved front frame. Accordingly, when the hook is pushed upward away from the retained portion, the lugs of the rib can be disengaged from the end portions of the engagement groove.

1. Field of the Invention
This invention relates to a pair of eyeglasses, more particularly to a pair of eyeglasses with a replaceable lens unit which is able to be easily replaced with a new one.
2. Description of the Related Art
This invention is an improvement of a pair of conventional eyeglasses which includes an eyeglass frame and a pair of lenses. The eyeglass frame consists of a curved front frame and two bows which are respectively coupled with two ends of the front frame in a known manner. Because the lenses are mounted securely on the annular front frame of the eyeglass frame, when the wearer desires to change the lenses, a new pair of eyeglasses is needed to substitute therefor. This type of eyeglasses cannot satisfy the need of consumers from an economical standpoint.


A closed-loop control system for altering the optical characteristics of a patient's cornea includes an algorithm for predicting the shape of the cornea after one or more gas bubbles resulting from intrastromal photoablation have collapsed. Patient data can be used as an input for the algorithm, which is then run to prepare an initial treatment plan for a corneal alteration. The initial plan typically includes a plurality of intrastromal photoablation locations and corresponding ablation energies. After photoablation of plan location(s) and before the resulting bubbles collapse, a real-time wavefront shape for light passing through the cornea is measured. The wavefront is then used in the algorithm to predict a post bubble collapse cornea shape and to generate an updated treatment plan. The procedure then continues by ablating location(s) identified in the updated treatment plan. Wavefront measurement and plan updating can be repeated as many times as desired.

It is well known that the optical characteristics of an eye can be altered through laser surgery. For example, U.S. Pat. No. 6,050,687 which issued to Bille et al. for an invention entitled "Method and Apparatus for Measuring the Refractive Properties of the Human Eye," discloses a laser system that can be used for such purposes. In any event, a consequence of photoablation, is that individual cells in the tissue are vaporized. Gas is, therefore, a product of photoablation. When a surgical laser procedure involves the superficial photoablation of tissue, the fact that such gases are created does not cause much of a problem. This is not the case, however, when internal tissue is photoablated.
For specific surgical procedures that involve the intrastromal photoablation of corneal tissue, it is known that such photoablation results in the formation of tiny bubbles in the stroma. Further, it is known that the formation of these bubbles introduces aberrations that change the optical characteristics of the cornea. The reason for this change is essentially two-fold. First, the gas bubbles have a different refractive index than that of the surrounding stromal tissue. Second, and perhaps more important, the gas bubbles tend to deform the stroma and, thus, they alter its refractive effect on light passing through the cornea. In a controlled surgical procedure these induced aberrations must be accounted for.
Wavefront analysis provides a useful and helpful conceptual tool for determining the effect a particular medium or material (e.g. the cornea of an eye) will have on a light beam, as the beam passes through the medium (material). For wavefront analysis, a light beam can be conveniently considered as being a so-called "bundle" of component light beams. These component light beams are all mutually parallel to each other, and when all of the component beams of a light beam are in phase with each other as they pass through a plane in space, it is said they define a plane wavefront. However, when a light beam passes through a medium, the medium will most likely have a different refractive effect on each of the individual component beams of the light beam. The result is that the phases of the component light beams will differ from each other. When now considered collectively, these component light beams will define something other than a plane wavefront. In summary, a particular wavefront will define the refractive effect a medium, or several media, have had on a light beam.
Insofar as laser surgery is concerned, it is the objective of such surgery to remove unwanted aberrations from the light beams that a patient perceives visually. As implied above, wavefront analysis can be a helpful tool in evaluating and determining the extent to which refractive properties of a cornea may need to be altered or corrected. Indeed, such an analysis has been helpful for surgical procedures involving superficial photoablation. For example, U.S. Pat. No. 6,428,533B1 which issued to Bille for an invention entitled "Closed Loop Control for Refractive Laser Surgery (LASIK)," and which is assigned to the same assignee as the present invention, discloses such a system.
As recognized by the present invention, when intrastromal photoablation is to be performed, and the evaluations and determinations of a wavefront analysis are put into practice, it is desirable to establish control over each individual component beam defining a wavefront. With this control, induced aberrations such as the aberrations mentioned above, can be accurately compensated for, and the overall control of the procedure enhanced.
As further recognized by the present invention, the temporal effect of intrastromal photoablation can be characterized as having three distinct periods. The first period, which typically lasts for about 30-60 minutes after tissue photoablation, is characterized by the presence of a gas bubble in the stroma. The second period, on the other hand, occurs after the gas bubble has collapsed. During this second period, photoablation induced stresses remain in the stromal tissue that previously surrounded the gas bubble. These induced stresses relax during the second period, and, during this relaxation, the curvature of the cornea changes. Eventually, the curvature of the cornea stabilizes. Thus, the onset of the third period corresponds to the time when the induced stresses have relaxed and the shape of the cornea has substantially stabilized. This stable shape, in turn, represents the long-term surgical performance of the ablation. Typically, the third period begins approximately 1-30 days after the ablation.
In general, a single procedure for corneal corrections can require hundreds of intrastromal photoablations, each of which results in the formation of a corresponding gas bubble. For these corneal corrections, a typical laser pulse repetition rate of approximately 10 kHz is used. With this pulse repetition rate, it can be appreciated that some ablations will occur during a procedure before all of the previously created bubbles have collapsed. Indeed, it is typical for the entire procedure to be completed before any of the gas bubbles have fully collapsed. With the above in mind, it is possible to measure a wavefront between successive ablations which is indicative of corneal shape. This real-time information can then be used to update a treatment plan and thereby revise the planned position and size of subsequent ablations during a procedure.
In a complicated procedure such as a corneal reshaping, it would be helpful to predict the long term surgical effect of an ablation (i.e. the eventual corneal shape after bubble collapse and relaxation of photoablation induced stresses). Preferably, this prediction could be made in real-time from a wavefront measurement that is obtained during a procedure (i.e. after an ablation but before the resulting bubble has collapsed). This information could then be used to modify a treatment plan during the procedure, to increase the overall accuracy of the procedure. As recognized by the present invention, however, the relaxation of induced stresses which occurs during the second period described above, and its effect on corneal shape, is somewhat unpredictable. At least this is so using current models. On the other hand, the inventors have determined that it is possible to estimate the corneal shape after bubble collapse (i.e. at the end of the second period described above). Moreover, this can be done with real-time wavefront data measured between successive bubbles during a procedure.
In light of the above, it is an object of the present invention to provide systems and methods suitable for the purposes of using real-time wavefront data measured during an intrastromal photodisruption procedure to improve the surgical performance of the procedure. It is another object of the present invention to provide systems and methods for performing an accurate optical correction which accounts for the relatively long-term effects associated with the relaxation of photoablation induced stresses. It is yet another object of the present invention to provide systems and methods for intrastromal photoablation which are easy to use, relatively simple to implement, and comparatively cost effective.

Closed loop control for intrastromal wavefront-guided ablation with fractionated treatment program


In a tap having a lead part and a complete thread part contiguous to the lead part, a relief is formed on at least one of a leading flank and a following flank of each of a plurality of thread ridges formed on the rear end side of the lead part and each of a plurality of thread ridges formed on the front end side of the contiguous complete thread part, so that the portion of an internal thread having been cut already by the preceding cutting edge may not be cut again and widened by the succeeding cutting edge.

A threaded portion of a tap used for cutting an internal thread in a workpiece consists of a lead part formed on the leading side and a complete thread part formed on the following side.
When such a tap is used to cut an internal thread in a workpiece, its lead part first cuts into the workpiece thereby gradually generating a thread groove, and the complete thread part then makes thread engagement with the groove to act as a guide guiding the advancing movement of the tap itself.
However, the tap used for cutting the internal thread in a workpiece has various different angular factors, such as, the rake or hook angle of each cutting edge at its lead part, the radial angle on the lead as well as the inclination angle at the circumference of each cutting edge, and the radial thread relief angle at the flank face of each cutting edge relative to the normal helical direction of the thread. In addition, the thrust that may be large or small is imparted to the tap itself. As a result, the advancing movement of the tap in its axial direction tends to fluctuate, and the force of reaction due to the resistance to cutting tends to act on the tap. This leads to such a problem that the front end of the generated internal thread engaged by the lead part of the tap tends to be widened or flared, resulting in an undesirable degradation of the dimensional precision of the flank faces of the generated internal thread.
With a view to deal with such a problem, various proposals for improvements have been made, as disclosed in, for example, JP-A-60-194425 (UM) which relates to a spiral fluted tap. According to the disclosure of the cited application, a planar negative relieving having a substantially constant width is formed to extend from the root towards the crest on the leading flank or the following flank along the line of intersection between the wall face of the flute and the flank of each thread ridge. However, it is apparent that, according to those proposals intending improvements, a large resistance is encountered during the cutting operation, because the negative relieving described above acts to effect plastic cutting rather than mechanical cutting. As a result, the phenomenon of frictional fusion similar to that encountered with a built-in edge of a turning tool tends to occur at the relieved portion. Therefore, with the increase in the number of times of use (cutting) of the tap, the dimensional precision of the flank faces of the finished internal thread has been inevitably degraded together with the shortened useful service life of the tap itself.


A digital data clock control loop for reconstructing the asynchronous data clock in a recording channel. The Discrete Time Control Loop (DTCL) implementation is suitable for monolithic digital embodiment and uses no analog components, providing stable operation at widely varying clock rates without hardware oscillators. The DTCL also can supply the clocking function to recover synchronous samples in an asynchronous data sampling system.

1. Field of the Invention
This invention relates to a digital data clocking system for asynchronous data transfer and, more specifically, to a recording channel data clock control loop without analog timing elements.
2. Discussion of the Related Art
A magnetic or optical recording channel is designed to accept data for storage and deliver the same on retrieval demand at a later time with reasonable access delay and without errors. Self-clocking modulation codes are employed to ensure an adequate minimum rate of signal transitions for clock synchronization during data retrieval without exceeding the maximum transition storage density of the magnetic or optical medium during data storage. Such modulation codes are run-length-limiting (RLL) codes that represent a one-to-one mapping of binary data into a constrained binary sequence that is then recorded on the recording medium in the form of a modified Non-Return-to-Zero (NRZI) waveform.
In a NRZI waveform, the maximum and minimum number of spaces between consecutive transitions correspond to the maximum and minimum run lengths of zeros between two consecutive ones in the corresponding binary sequence, as is known in the art. Thus, such modulation codes fall within the class of RLL codes characterized by the parameters (d,k) where d represents the minimum and k represents the maximum number of zeros between two consecutive ones in the coded sequence. These codes are the result of a steady evolution of waveform design coupled with improvements in magnetic and optical recording channels, including improved clocking and signal-detection processes.
In a recording channel, the read clocking function is the key to restoring digital data following transition detection. The read clocking function separates the synchronous data clock signal from the self-clocking data signal in the recording channel. It is usually performed by a phase-locked oscillator (PLO), which regenerates the synchronous data clock waveform in response to the flow of self-clocking signal waveform peaks from the magnetic or optical transition detector. Although this phase control loop can be primarily digital, as with a digital phase-locked loop (DPLL), some analog components are necessary. Even in a DPLL, the digitally-controlled oscillator (DCO) employs analog components. Ideally, a digital implementation without analog components is desired because it permits an inexpensive and efficient monolithic device to perform accurate read clocking without calibration drift or adjustment.
Practitioners have suggested progressive improvements to the DPLLs known in the art. A comprehensive survey of the DPLL art is provided by William C. Lindsay et al, "A Survey of Digital Phase-Locked Loops", Proc. IEEE, Vol, 69, pp. 410-431, April 1981. These improvements are motivated by the several disadvantages of the analog clock recovery procedures known in the DPLL art. The most obvious disadvantage is that the VCO used to control the clock frequency is an analog component. The analog VCO gain and operating points may depend upon the manufacturing processes. The components may be relatively costly to build and calibrate, thereby offsetting the cost advantage of a digital system implementation. Another disadvantage is the phase error correction delays inherent within a VCO control loop. Tightening the control loop requires tighter restrictions on variations in the input data rate. This may not be feasible in a typical magnetic tape product or in optical data storage systems having variable linear read and write speeds. Moreover, equalization and detector improvements in the recording art may increase the PLL feedback loop delays and exacerbate the problem.
In U.S. Pat. No. 4,987,373, David C. Soo discloses a PLL circuit that uses analog sample detection techniques in his phase detector and the loop filter circuitry in an attempt to avoid some of the difficulties inherent in analog components. However, Soo requires an analog clock generator to drive his sampled-data phase detector circuit.
In U.S. Pat. No. 4,797,845, Eduard F. Stikvoort discloses a PLL coefficient generator for generating deviation signals for use in a sample rate converter with a non-rational sampling ratio. Stikvoort uses synthetic low-rate clock pulses in addition to the normal phase detector clock pulses to make his phase error correction process less subject to the common weaknesses of analog component problems. However, application of his teachings is limited to sample rate converters.
In U.S. Pat. No. 4,912,729, Antonia C. Van Rens et al disclose a DPLL circuit comprising a discrete-time oscillator corrected in phase and frequency to track a sampled input signal. Although their PLL circuit can be constructed entirely by means of digital elements, they use a discrete-time oscillator that drifts rapidly in the absence of frequent input transitions during longer RLL codes, which prevents application of their invention to many useful asynchronous channels.
Thus, despite numerous efforts in the art, there still exists a clearly-felt need for a purely digital implementation of a recording channel clock controller for regenerating and restoring digital data after detection. The related unresolved problems and deficiencies are clearly felt in the art and are solved by this invention in the manner described below.

Clock controller employing a discrete time control loop method for clocking data in an asynchronous channel

International Business Machines Corporation


A tablet device determines a spatial relationship between the tablet device and a protective cover. The tablet device operates in accordance with the spatial relationship.

Recent advances in portable computing includes the introduction of hand held electronic devices and computing platforms along the lines of the iPad™ tablet manufactured by Apple Inc. of Cupertino, Calif. These handheld computing devices can be configured such that a substantial portion of the electronic device takes the form of a display used for presenting visual content leaving little available space for an attachment mechanism that can be used for attaching an accessory device.
The display can include various user interface features that can interact with external stimuli to convey information from an end user, for example, and processing circuitry in the hand held computing device. For example, the display can include touch sensitive elements that can be used to enable various multi-touch (MT) functions. When the accessory device takes the form of a cover, the handheld computing device can be operable in modes consistent with the presence of the cover. For example, when the handheld computing device has a display, the presence of the cover can render the display unviewable. In order to save power, the unviewable display can be rendered temporarily inoperable until the cover is moved or otherwise repositioned to expose the display.
Therefore, accurate and reliable techniques for determining selected aspects of an accessory device are desired.

Peek mode and graphical user interface (GUI) experience