Systems and methods for receiving ADS-B messages in environments where multipath propagation corrupts the messages or blocks the reception of the messages. An exemplary system combines RF signal processing and digital signal processing techniques to make it possible to receive ADS-B messages in the presence of multipath reflections from nearby structures and/or farther out structures. The system uses an array of horizontally spaced antennas. The RF signals from the antennas are combined by the receiver so as to form a set of beams with different azimuth antenna patterns to increase the probability that the multipath does not combine destructively with the line-of-sight path in at least one of the beams. This effectively removes multipath reflections where the delay of the multipath relative to the line-of-sight path is less than 100-200 nanoseconds. The system is also configured to remove multipath reflections with greater delays relative to the line-of-sight path.

When aircraft are operating on the airport surface, it has been observed that reception of automatic dependent surveillance-broadcast (ADS-B) squitters from aircraft that are within line-of-sight of the ADS-B receiver is often not reliable. A closer examination of structures in the vicinity of the airport has revealed that multipath reflections from these structures are the likely explanation for the missed reception of the ADS-B squitters. When the aircraft is in the air or moving at take-off or landing speeds, the effect of the multipath reflection is inconsequential and may result in the loss of a single squitter. However, when the aircraft is stationary or moving slowly, the multipath reflections may hide the true ADS-B squitters.
The most common source of multipath in flat open areas such as airport runways is a ground reflection. However, the distances between aircraft operating on the airport surface are too short for the ground reflections to cause deep fades. Instead, reflections from buildings, other aircraft, etc are more likely to be the root cause of deep fades.
In order to understand the conditions under which multipath produces deep fading on the airport surface, we need to make use of the following physical relationships between the direct path and the reflected multipath.
The total received signal power, Pr, due to the direct and reflected signals is given byPR=PT[λ/4πd]2|1+R(θr)ejΔ|2
where R(θr) is the reflection coefficient of the reflecting structure. The reflection coefficient has magnitude between 0 and 1 and phase between 0 and 180 degrees. Perfect cancellation between the direct path and the reflection occurs when the reflection coefficient R(θr) has magnitude unity and the phase of the reflection coefficient plus the relative phase shift Δ due to the difference in the distances traveled by the direct and reflected path add up to an odd multiple of 180 degrees.
The phase difference Δ and the difference in time of arrival (delay) τ between the direct and the reflected signals depends on the difference in the distances traveled, i.e.Δ=2π(s1+s2−d)/λ=2πfτ
where d, s1 and s2 are distances, λ=c/f is the wavelength, c is the speed of light and f=1090 MHz is the ADS-B carrier frequency.
In general, the amplitude and phase of the reflection coefficient depend on the angle of reflection, θr, the polarization of the signal, the dielectric and conducting properties of the ground, and the frequency, i.e.R(θr)=[sin θr−χ(θr)]/[sin θr+χ(θr)]
where
χ(θr)=[(∈r−cos2 θr)−j60σλ]1/2/[∈r−j60σλ], polarization perpendicular to reflecting surface
χ(θr)=[(∈r−cos2 θr)−j60σλ]1/2, polarization parallel to reflecting surface
where ∈r is the dielectric constant of the reflecting surface relative to unity in free space, σ is the conductivity of the reflecting surface in mhos/m and θr is the reflection angle.
An illustration of multipath propagation due to reflections from structures on the airport surface when one aircraft at location A1 on the airport surface is broadcasting ADS-B messages and another aircraft on location A2 is attempting to receive the messages is shown in FIG. 1.
The separation distance between the aircraft is d. Multipath interference occurs when a reflecting structure at location R is oriented relative to the two aircraft so that a signal transmitted by the aircraft in location A1 is reflected in the direction of the aircraft in location A2. The reflecting surface may be another aircraft or vehicle on the airport surface, or a building or any other fixed structure. The distance traveled by the reflected signal, s1+s2, is greater that the distance, d, traveled by the direct line-of-sight path between the two aircraft.
The time delay or difference in arrival time, τ, between the direct and reflected paths is given byτ=(s1+s2−d)/c  (1)
where c=3×108 m/s is the speed of light.
An ellipse with major axis (−a, a) and minor axis (−b, b) and focus points at A1 and A2 plots the locus of all possible locations where a reflecting surface R can produce a multipath reflection with time delay τ relative to the direct path along the major axis of the ellipse. The angle of arrival φ1 or φ2 of the multipath relative to the angle of arrival of the direct path can be anywhere between 0 degrees when the reflecting point is in front of the receiving antenna along the major axis of the ellipse to 90 degrees when it is off to the side and up to 180 degrees when it is behind the receiving system along the major axis of the ellipse.
The ADS-B squitter messages broadcast by each aircraft consist of sequences of 112 pulses of 500 nanoseconds' duration. Each pulse is broadcast within a 1 microsecond interval either in the first 500 nanoseconds or the second 500 nanoseconds slot. The slot occupied by each pulse indicates whether the information bit represented by the pulse is a "0" or a "1". This is known as pulse position modulation.
The effect of multipath reflection on the reception of the sequence of pulses in an ADS-B message and the appropriate mitigation depend on the delay between the multipath reflection and the direct path as discussed in the paragraphs below.
When the difference in travel time, i.e., time delay, between the direct and reflected paths is small compared to the 500 nanosecond pulse duration, i.e., when τ<50 ns, the pulse that is received via the reflected path arrives practically within the same slot interval as the direct path pulse. In this case the two overlapping pulses may add up if the phase of the reflected pulse is the same as the phase of the direct path pulse in which case no harm is done. Or the two overlapping pulses may cancel if they have nearly equal amplitudes and they are 180 degrees out-of-phase. If the transmitting and receiving aircraft are stationary or moving slowly the entire sequence of pulses in an ADS-B message will suffer from destructive multipath cancellation resulting in a failure to receive the transmitted pulse, as illustrated in FIG. 2.
An idea of the extent of airport surface area over which ADS-B squitter message reception is vulnerable to missed squitter reception due to multipath with short delay offset may be obtained from the dimensions of the major axis and the minor axis of an ellipse corresponding to multipath reflections with 50 ns time delay. Table 1 below shows the dimensions of the 50 ns time delay ellipse as a function of the separation distance d between the transmitting aircraft and the receiving aircraft. Reflecting structures that are within an elliptical boundary with these dimensions will produce multipath reflections with short delays.
TABLE 150 ns Time Delay Ellipse DimensionsSeparationMajor AxisMinor AxisDistance d (m)Dimension 2a (m)Dimension 2b (m)10011556.820021578.930031596.0400415110.6500515123.4600615135.0700715145.7800815155.6900915165.010001015173.8
Like ground reflection multipath, short delay multipath can be mitigated by using more than one antenna and receiver (diversity) to receive the ADS-B messages. However, unlike ground multipath, the use of top mounted and bottom mounted antennas do not necessarily provide mitigation against short delay multipath due to reflections from structures to the side of the LOS path if the top and bottom mounted antennas have omni-directional patterns.
To understand how pulse cancellation due to short delay multipath reflections from side structures can be mitigated PR=PT[λ/4πd]2|1+R(θr)ejΔ|2 is re-written asPR=PT[λ/4πd]2G1(0)G2(0)|1+A(φ1,φ2,G1,G2)R(θr)ejΔ|2
where A(φ1,φ2,G1,G2) is an amplitude factor which is proportional to the ratio of the transmitting and receiving antenna gains G1(φ1) and G2(φ2) in the direction of the reflected path to the antenna gains G1(0) and G2(0) in the direction of the direct path, i.e.
When the difference in travel time between the direct and reflected paths is in the order of or greater than the 500 nanosecond pulse duration, i.e., when τ>450 ns, the pulse that is received via the reflected path arrives in the next or later slot interval, thereby interfering with the correct decoding of the pulse position in subsequent pulse intervals as illustrated in FIG. 3. The delayed pulse may arrive in the unoccupied slot during the current or next pulse interval so that a pulse is received in both slot positions making it difficult to determine which slot position is the correct one. Or the delayed pulse may arrive in the same slot as the pulse transmitted in the next interval in which case cancellation may occur if the two pulses are 180 degrees out of phase or they may add up if they are in phase.
In any case, long delay multipath produces "intersymbol interference" that makes correct decoding of the sequence of ADS-B squitter message not possible.
Table 2 below shows the dimensions of the 450 ns time delay ellipse as a function of the separation distance d between the transmitting aircraft and the receiving aircraft. Reflecting structure outside an ellipse with these dimensions will produce multipath reflections with long delays.
TABLE 2450 ns Time Delay Ellipse DimensionsSeparationMajor AxisMinor AxisDistance d (m)Dimension 2a (m)Dimension 2b (m)100235212.6200335268.8300435315.0400535345.2500635391.4600735424.6700835455.2800935484.09001035511.210001135536.8Table 2 shows that multipath reflections with delays longer than 450 ns can be produced within an airport surface of not too big an extension. To get an idea of what the maximum delay of multipath reflections might be, Table 3 below shows the dimensions of a 2000 ns time delay ellipse (i.e., multipath reflections with delays up to 2000 ns possible at large airports).
TABLE 32000 ns Time Delay Ellipse DimensionsSeparationMajor AxisMinor AxisDistance d (m)Dimension 2a (m)Dimension 2b (m)100700692.8200800774.6300900848.64001000916.65001100979.860012001039.270013001095.480014001149.090015001200.0100016001249.0
Diversity reception with multiple antennas with different azimuth antenna patterns does not prevent incorrect decoding of ADS-B message bits when the delayed pulse arrives in a later unoccupied pulse position. In this case, a pulse is received in both possible pulse position slots making it impossible for the receiver to differentiate between the direct path pulse and the reflected path pulse, especially when the reflecting structure is a highly conducting metallic object so that both pulses have equal or nearly equal amplitudes. Traditionally, digital communications systems that suffer from destructive interference from multipath with delay that is longer than the duration of transmitted modulation symbols use adaptive equalization to continuously estimate and cancel the interference that one symbol inflicts on subsequent symbols (inter-symbol interference). The adaptive equalizers may be classified as linear equalizers if they employ a linear Finite Impulse Response (FIR) filter with adaptive "tap weights" or as nonlinear decision feedback equalizers if they employ a linear FIR as well as a feedback FIR filter to cancel the inter-symbol interference. The adaptation of the linear or nonlinear FIR filter tap weights may be classified as pilot or training data-assisted equalization if known data is interleaved with information bearing symbols or as blind equalization if no known data is interleaved. In order for the tap weights of the adaptive filters to converge to the optimum values that result in the cancellation of the inter-symbol interference, the equalizer must be trained for a sufficiently long period of time at the beginning of a transmission and then they must continue adapting to maintain the tap-weight settings at their optimum value if the channel multipath is slowly changing. Therefore adaptive equalizers are most effective when used in systems that transmit data continuously over a channel with multipath that changes in time or which transmit long bursts of data preceded by a sufficiently long training preamble.
In the case of ADS-B messages, the waveform has already been defined and cannot be modified to make it more suitable for use with the above mentioned adaptive equalization techniques. The ADS-B message is very short (112 bits long) and the preamble consists of only four pulses of known position (too short to train an equalizer). The entire ADS-B message duration including the preamble and extended squitter message is less than 128 microseconds. The short preamble makes the use of adaptive equalization techniques difficult at best.
Other types of receivers that are commonly used in multipath channels are RAKE receivers. A RAKE receiver combines ("rakes") the multipath coherently to improve the signal-to-noise ratio. RAKE receivers are employed when the multipath does not cause inter-symbol interference. They are used in systems where gaps between symbols are interleaved to allow for the reception of the multipath.
In the case of the ADS-B message, the pulses in the message either have one pulse interval gap between them if they represent 00 or 11 bits, or the pulses are next to each other if they represent a 10-bit sequence or they have a two pulse gap if they represent a 01-bit sequence. When the transmitted pulses are adjacent each other, multipath that is 180 degrees out-of-phase with the direct path and which are delayed in the order of one pulse duration will cancel the next pulse. So a RAKE receiver will not be able to protect against this type of multipath interference and if there is no error correction, then this bit loss cannot be recovered.

ADS-B receiver system with multipath mitigation


The invention provides a process for making a mat particularly a washable dust control mat, having a fabric layer and a rubber backing layer with a border extending beyond the fabric layer using a press which heat-cures the rubber and adheres it to the fabric and employs an inflatable bag to apply pressure by pressing the layers against a heated platen, wherein a frame defining the extent of the border is located between the bag and the platen, and wherein the bag applies pressure to the assembled layers including the border portion of the backing layer. The frame can act as a dam for preventing outward movement of the rubber and provide an integral thickened border; in some cases it also provides a guillotine for trimming the rubber during pressing.

This invention relates to the manufacture of mats, rugs and carpets, particularly mats, rugs and carpets where a rubber (natural or synthetic) backing sheet is cured and heat-bonded under pressure to the back of a fabric layer leaving a rubber border extending beyond the fabric layer. It also relates to mats, rugs and carpets as such and to apparatus for use in producing them.
The invention is of particular utility in the manufacture of washable mats, rugs and carpets such as dust-control mats. The term xe2x80x9cwashablexe2x80x9d means washable by immersion and agitation in water or other cleaning fluid usually followed by spin extraction and tumble drying. The term xe2x80x9cmatxe2x80x9d is used hereinafter in a wide sense to include rugs and carpets.
Dust control mats have conventionally been made by first laying down an uncured sheet of rubber, placing a mat fabric layer on top of it leaving the required border (e.g. 2 cm), and placing the assembly of the two layers in a heated press which cures the rubber and bonds it to the fabric. The layers are conveniently assembled on a horizontally movable carrier which can be moved into and out of the press on rollers, the carrier having an upper layer of flexible material secured around its edges to form an inflatable bag. Once in the press the carrier can be raised with hydraulic or pneumatic rams beyond a point where support blocks can be moved horizontally beneath the carrier (so that the rams do not sustain the pressing force). The bag is then inflated to press the mat assembly against a heated platen disposed above it and heated to say 170xc2x0 C. by pressurised steam in conduits in the platen. The advantage of applying pressure using a bag is that a bag conforms to the contour of the mat assembly and applies an even pressure. After curing the pressurised air in the bag is released and the bag evacuated by applying suction or using the hydraulic or pneumatic rams to squeeze the air out. The support blocks are removed and the rams lower the carrier so that it can be removed from the press.
This arrangement is generally preferred as the operator can easily locate the fabric layer on the backing layer when the fabric layer is on top and it is desirable to apply the heat from the fabric side so as to ensure proper bounding of the two layers so that they do not separate in use. However it is possible to reverse the arrangement so that heat is applied to the rubber side and/or the fabric layer is beneath the rubber layer. Also, if the range of movement of the bag surface is sufficient, it is possible to omit the rams and the blocks because the assembly is sufficiently close to the heated platen when it enters the press.
It is conventional to provide release sheets of non-stick material such as polytetrafluoroethylene or silicone materials between the fabric layer and the platen and between the bag and the rubber. It is also conventional to provide a light aluminum (or other metal) moulding sheet in contact with the rubber, the moulding sheet having holes or depressions which mould projections (cleats) or patterns (e.g. logos) into the rubber. Silicone rubber moulding sheets can also be used.
The rubber flows outwardly during pressing to form edges which taper down to a very small thinness. These edges are prone to tearing and extend by unpredictable distances. Hence it is necessary in practice to trim the cured backing sheet with guillotines or knives. Finally it is conventional to provide small openings in the rubber backing to allow passage of water during laundering, particularly during spin extraction. This can be achieved by running the mats between a spiked roller and a backing roller having grooves aligned with the spikes.
The three steps of (a) assembling the layers and operating the press, (b) trimming the edges of the backing, and (c) piercing the backing, are labour-intensive and we have sought ways of improving the efficiency of the overall process.
According to the invention, we provide a process for making a mat (preferably a dust control mat) having a fabric layer and a rubber backing layer using a press which heat-cures the rubber and adheres it to the fabric and employs an inflatable bag to apply pressure by pressing the layers against a heated platen, wherein a frame defining the extent of the periphery of the mat is located between the bag and the platen and wherein the bag applies pressure over substantially the whole area of the backing layer.
According to a preferred embodiment of the invention, we provide a process for making a mat (preferably a dust control mat) having a fabric layer and a rubber backing layer with a border extending beyond the fabric layer using a press which heat-cures the rubber and adheres it to the fabric and employs an inflatable bag to apply pressure by pressing the layers against a heated platen, wherein a frame defining the extent of the border is located between the bag and the platen, and wherein the bag applies pressure to the assembled layers including the border portion of the backing layer. A border beyond the fabric layer is normally provided but the invention is operable without any border or with a very small border e.g. 1-2 mm wide if the frame cannot cut through the fabric layer; for convenience only, the following description refers to mats with borders.
Preferably, rubber accumulates in the areas immediately inward of the frame while it is still flowable such that a thickened reinforcement is provided in these areas of the cured backing layer. Thus, according to another aspect of the invention, we provide a mat in which a rubber backing sheet has an integral thickened peripheral region.
Preferably the bag applies pressure to the fabric side of the assembled layers although the alternative arrangement where it applies pressure to the backing side can be used.
The press may take a number of forms e.g. as described in U.S. Pat. No. 4,447,201 to Knudsen, the contents of which are incorporated herein by reference. This patent describes the more common movable frame type of press. However, fixed frame presses such as that described in EP-A-367441 may be used. A number of presses suitable for making dust control mats are commercially available from Shaw-Almex USA Inc. of 3529-H Church Street, Clarkston, Ga. 30021, USA.
The frame is normally of metal and in one preferred arrangement, can for example be part of (formed e.g. by machining, moulding or casting) or connected to (e.g. adhered to or welded to) the moulding sheet referred to above. Thus, according to a further aspect of the invention, we provide a moulding sheet for use in making mats by heat-compression moulding an assembly of a rubber backing layer and a fabric layer, the sheet comprising or being associated with a frame defining the mat periphery.
The frame can be greater or smaller in area than the initial area of the backing layer. If it is greater in area than the initial area of the backing layer it acts as a dam; if it is smaller it acts both as a guillotine and a dam. The latter arrangement is preferred in which case the frame needs to have a cross-section which is narrow at the top or bottom to provide a cutting action.
In order that the operator can ensure that the border is in the correct position, another preferred arrangement is for the fabric layer and for the frame (which in this case is separate from the moulding sheet) to be both placed on top of the backing layer such that in the press the bag bears down on both the fabric layer and the frame, the latter being forced downwardly through the backing layer.
It is preferred to make the frame of metal rod, particularly of circular section with the section diameter being preferably about twice the backing layer thickness in the central part of the finished mat. If the diameter (height) is too small, the thickened rubber layer in the border may be too thin; if it is too great, the inherent stiffness of the bag material may prevent adequate compression in the angle between the frame and the top of the backing layer. A circular section rod may provide a concave end to the border but this has been found not to be a disadvantage. A circular section rod of appropriate diameter is sharp enough to be pushed through the rubber, during initial operation of the press, while being blunt enough to avoid damage to the bag.
Normally the finished mat will be rectangular and a rectangular frame will be used. However, other shapes such as circular or rectangular with rounded corners can be used. Also, the sides of the frame will not necessarily be joined together but this will normally be the case so that unwanted movement during pressing is avoided. Thus the frame may be interrupted and define only part of the mat periphery e.g. one or more sides of the frame may be omitted.
It will be seen that the process described eliminates a subsequent trimming operation since any excess rubber outside the frame can be peeled away after pressing. It is also possible, according to a preferred feature of the invention, to simultaneously pierce the backing to provide the small holes described above. This can be achieved for example by providing spikes on the moulding sheet referred to above. The spikes need not necessarily pass completely through the backing since a thin membrane at the end of the hole which they provide will be broken during subsequent use of the mat. The moulding sheet may be shaped to provide dish-like depressions around the holes as described in our GB patent application GB-A-2275869.
As mentioned above, a further advantage of the invention arises from accumulation of rubber in the border area where the maximum strength of the backing layer is required. This means that the thickness over the main area of the mat can be reduced e.g. from 2 mm to 1 mm because the accumulation in the border area can double the thickness. This of course means that the amount of rubber used is substantially reduced. Also the use of a frame reduces wastage simply because there is no longer a substantial tapered peripheral area of backing layer which has to be trimmed off to achieve the desired edge thickness.
Instead of using a greater overall thickness to achieve the required border thickness, some previous mats have a reinforced border made by heat fusing an extra layer of rubber thereon. This is labour-intensive and can lead to rippling due to differential shrinkage of the two rubbers during laundering. The present invention can be used to overcome these disadvantages.


A display system suitable for use inside an MRI system bore to display images to a patient undergoing an MRI procedure. The display system includes a curved display structure fitted inside the MRI bore, and having a width and length sufficient to present images to the patient inside the tunnel. First and second EMI shielding layers sandwich the curved display structure. A display electronics module is electrically connected to the curved display structure to provide video drive signals to the curved display structure. A housing for the display electronics module is configured to provide shielding to prevent EM signals from within the housing to affect MRI image processing.

The magnetic resonance imaging (MRI) tunnel or bore is a tight tunnel and for some patients creates claustrophobia effect. For the past 25 years or so, there has been many different technologies to overcome the issue of claustrophobia for the patients undergoing the MRI procedures.
Some solutions in the past have been effective, but there is room for better technology with lower cost, ease of use and improved effectiveness than the current systems.
Following are descriptions of several systems in the market today.
Projection systems are known: A screen is located on either end of the magnet bore while patients look through a reflective mirror to watch the screen. This method is time consuming and, depending on the type of procedure. For example, in a lumbar scan procedure, the patient's feet go inside the bore first. Therefore, using a reflective mirror will not work, as the patient will not see the display because the stomach will block the view of the screen.
Another system uses an LCD panel on the back and outside of the bore and is similar to the Projection System.
Virtual reality goggles are more effective because patients cannot see that they are inside the tunnel of the MRI. There are some issues such as that the goggle might not fit all the patients during the head scan, due to the small size of the head coil and because some patients have large heads.
Another system uses a projection screen with the actual screen inside the bore, with the screen attached to the table moving with the patients. This has disadvantages, in that the patient is still are aware of the ceiling of the MRI bore, and using mirror to see the screen is not practical for all the scans, particularly if the patient goes inside the bore with feet in first. It is also very costly.
In most of the new MRI suites, the building manufacturer adds a color changing LED in order to make the room feel more pleasant, but once the patient is inside the bore, they cannot see the outside color-changing LED.
Another system may have a system with an LCD panel outside the bore with a built-in mirror for the patient to see the LCD panel. Some MRI magnet rooms may have an LCD monitor hung from the ceiling for the patient to see some videos before being moved into the MRI bore for an imaging procedure.


A power adapter has a solenoid actuated retaining latch controlled by an electronic circuit that detects the presence or absence of AC mains voltage. When the assembled AC-DC adapter and plug assembly are removed from the wall, the latch detects removal and unlocks the plug assembly for easy removal without undue force required by the user. The circuit is designed for minimal power consumption, and the solenoid only consumes power when it is engaging or disengaging the latch.

While the world long ago agreed on alternating (not direct) current (AC) for electrical "mains" (household) power delivery, there is no worldwide standardization on the configuration of AC connecting plugs or even AC voltages and frequencies. North America generally uses 110 VAC at 60 Hz, Japan uses 100 VAC at 50 or 60 Hz (depending on which part of the country you are in) and most of Europe uses 230 VAC at 50 Hz. Moreover, there are at least twelve different types of AC electrical plugs in widespread use throughout the world. North America and Japan settled on Types A (two-prong ungrounded) and B (three-prong grounded), whereas most of South America, Africa, Europe and Asia use Type C. Parts of Africa and parts of Asia use Type D, a smattering of countries in Europe, Asia and Africa use Types E, F, G and H, Australia and some businesses in Japan use Type I, Liechtenstein uses type J, and so on. None of these are compatible with one another, requiring worldwide travelers to bring along plug adapters to enable them to plug their AC devices into AC mains outlets of different countries. See www.trade.gov/mas/ian/ECW/characteristics.html.
Many modern digital appliances such as computers, tablets, smart phones and the like operate at voltages lower than the power mains, such as 5 VDC or 12 VDC. Such appliances often employ an external "power adapter" (step-down transformer or other circuit) to step the AC mains line voltage down to the particular lower voltage the appliance requires. Some such power adapters rectify the stepped-down voltage to convert alternating current from the power mains to direct current. These power adapters are often called "AC-DC power adapters."
To accommodate these various different worldwide power conventions, it is common practice to design such AC-DC power adapters with removable plug assemblies. This is beneficial to the manufacturer because it enables a single power adapter to be sold globally by shipping it with the specific plug assemblies required for each particular region. In some cases, the manufacturer provides several different interchangeable removable plug assemblies to the end user so the end user can use the same adapter in different global regions just by swapping between interchangeable plug assemblies. Users benefit by having a means of making the adapter compatible with different types of receptacles while traveling.
Some such interchangeable plug assemblies rely either on friction or a mechanical latch to retain the plug assembly in the body of the main adapter. These retaining systems can be confusing to the user, because without instructions printed on the device, it is not always clear which direction to pull or how much force to apply to the latch in order to disengage the plug assembly from the adapter body.
As a separate problem, AC-DC adapters which have the orientation of the AC prongs fixed relative to the adapter body will inevitably block an adjacent AC mains outlet depending on orientation of adjacent outlets in a power strip or wall socket. Some earlier solutions provided for rotation of the AC mains blades, but in such solutions the rotating blade mechanism is generally not detachable from the AC adapter body.
Further improvements are possible.

Electronically actuated retaining latch for AC-DC adapter removable plug assembly


A radar system and a method of operating a radar system. The radar system comprises a transmitter-receiver subsystem to transmit a series of electromagnetic pulses, to scan those pulses across an area of interest, and to receive echoes of the pulses. The radar pulses may be transmitted at a multitude of frequencies, each of which is in one of a multitude of channels. The radar system further includes a channel selection subsystem, first, to measure or sample the electromagnetic interference received by the transmitter-receiver subsystem in each of the channels of the radar system during each of at least selected scans of the radar pulses across the area of interest, and second, on the basis of those interferences measurements, to select automatically a channel of the radar system to transmit the radar pulses and to generate a signal identifying that channel. The transmitter-receiver subsystem includes a channel selector for receiving this signal from the channel selection subsystem, and in response to that signal, for selecting a frequency in the selected channel to transmit the radar pulses the next time those pulses are scanned across the area of interest.

This invention generally relates to multichannel, pulsed radar systems; and more specifically, to a multichannel, pulsed radar system having a subsystem to select the channel over which to transmit the radar pulses, and to a method of operating such a radar system.
In a pulsed radar system, electromagnetic pulses, usually ultra-high frequency radio waves, are transmitted and then reflected by objects that they encounter. The reflected pulses are received by the radar system, and information about the distance and azimuths of the objects producing the reflections can be derived from the delay between the time a particular pulse is transmitted and the time its reflection is received, as well as the direction of arrival of the reflected pulses.
The ability to receive information from the reflected radar pulses is affected by electromagnetic interference received by the radar system; and this interference, often referred to as jamming, generally includes all electromagnetic signals or energy received by the radar system other than the reflected radar pulses. Such interference may be caused by other electronic equipment or data transmission systems in the vicinity of the radar system, and, especially in the case of radar systems used for military purposes, electronic jamming may be intentionally created for the purpose of interfering with the radar system.
To minimize the effects of jamming, radar systems are often designed so that they may transmit and receive the radar pulses over a multitude of channels. With such a system, if significant interference is being received over one or a group of channels, another channel can be selected to transmit the radar pulses.
The channel over which the radar pulse is to be transmitted can be selected in a variety of ways. In a relatively simple case, the channel having the least amount of measured or estimated interference can be chosen to transmit the radar pulse. As a refinement of this relatively simple case, the interference being received over each channel can be measured or estimated, these raw values can be converted to qualified values that indicate the extent to which the interference affects the ability of the radar system to detect targets over each of the channels of the radar system, and the channel having the best potential to detect targets can be selected to transmit the radar pulses.
With both of the above-outlined general procedures, it is preferred to take a multitude of samples or measurements of the interference being received over each channel of the radar system each time the radar pulse is scanned across an area being monitored. Radar systems are currently available with up to a hundred or more channels; and with a radar system having such a large number of channels, it is difficult, first, to take a multitude of samples or measurements of the interference being received over each of the channels, and second, to process all of the acquired data properly and promptly to select the preferred channel to transmit the radar pulses.

Radar system and a method for operating a radar system


A disk apparatus comprising a precise positioning mechanism for finely displacing the information recording/reproducing mechanism in a radial direction of the disk, a coarse positioning mechanism for positionally displacing the information recording/reproducing mechanism in an information recording region in the radial direction of the disk, a coarse positioning mechanism driving circuit for controlling the drive of the coarse positioning mechanism upon receiving the drive signal in accordance with the drive signal generated by the reference speed generator, and a precise positioning mechanism driving circuit for controlling the drive of the precise positioning mechanism in accordance with a difference between the moving speed detected by the speed detector and the reference speed generated by the reference speed generator.

This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2000-301472, filed Sep. 29, 2000, the entire contents of which are incorporated herein by reference.
The present invention relates to a disk apparatus for performing recording/reproduction on a disk having information recording tracks, more specifically, it relates to a method of access control of a disk apparatus that performs positioning on a target track with use of two actuators: coarse and precise actuators.
In the field of optical disks, represented by DVDS, a disk having a diameter of 120 mm and a recording capacity of 4.7 GB has been brought into practical use in recent years. It is also expected that a disk having a recording capacity 3-4 times larger than that of this disk will be developed for practical use several years later. In order to cope with the increase in the recording density in the disk due to the increase in the recording capacity, more specifically, with the reduction of a track pitch, the servo precision having more precise positioning performance is now required for a disk recording/reproducing drive.
In fact, the highly precise positioning technique is essential for an optical disk apparatus to realize positioning of an optical spot in the direction of the diameter of a disk in the order of several nm on information recording tracks each having a pitch of 1 xcexcm or less. On the other hand, the access speed is also an important factor of the performance of the disk drive. A disk apparatus thus needs an access control technique capable of positioning, satisfying both the demands of high-speed and high precision.
Generally, in order to cover the diameter of a disk and realize highly precise positioning, the positioning of the optical spot is performed with two actuators, i.e., coarse and precise actuators. Access control, using these two actuators, in order to realize the access with high-speed and high precision, will now be described.
These two actuators, however, have some limitations.
The limitation of the precise actuator is that in displacement amount. In accordance with the increase of the optical disk in density, the requirements of the specification of optical elements used for the optical disk apparatus are becoming stricter. For example, the shift of an objective lens from the optical axis is required to be 50 xcexcm or less for a 4.7 GB DVD disk. If the shift is larger, the optical aberration becomes larger, and the recording/reproduction of information or detection of a positioning signal is adversely affected. A biaxial actuator is used as a precise actuator for positioning an objective lens, and has a limitation in the displacement amount.
The limitation of the coarse actuator is poor positioning precision. The coarse actuator is intended to coarsely position the objective lens in the direction of the radius of a disk. To cope with the requirement for reduction of manufacturing cost, the coarse actuator is formed of low-cost components: a sliding bearing and a low-cost positioning motor. Similarly, a driving force transmission mechanism is subject to many non-linear factors, such as friction and backlash. The positioning precision of the coarse actuator is as poor as 100 xcexcm.
It is now required for the optical disk apparatus to perform the positioning satisfying both high-speed and high precision with use of the two actuators without large displacement of the precise actuator. Some access control methods have been proposed to overcome the above-mentioned limitations by suitably making the two actuators cooperate with each other.
The conventional access control methods by the cooperation of the precise and coarse actuators will be described below in conjunction with the block diagrams of FIGS. 2 and 8. The constitution shown in these diagrams comprises a feed motor (a coarse actuator) 107 for moving an optical head 103, and an objective lens actuator (a precise actuator) 106 for positioning only an objective lens 102, in order to position the optical spot on a disk 101.
The access control according to the above-mentioned apparatus is performed with use of reflected light from the disk 101 after canceling the tracking control shown in FIG. 8.
In the tracking state, a track traversing signal generated when the optical spot traverses a track on the disk 101 is detected by a light detector 105 and a comparison processing circuit 108. The track traversing signal is input into a precise positioning mechanism controlling compensator 402 and then input into a precise positioning mechanism 106 via an amplifier 13 and a precise positioning mechanism driving circuit 15. The precise positioning mechanism 106 is controlled so as to move the optical spot to the same track. The track traversing signal is also supplied to a coarse positioning mechanism controlling compensator 403 and then input into a coarse positioning mechanism 107 via an amplifier 16 and a coarse positioning mechanism driving circuit 19. Similarly to the precise positioning mechanism 106, the coarse positioning mechanism 107 is controlled so as to move the optical spot to the same track.
Simultaneously to the staring the access, the tracking state is switched to the control state controlled by the control system constituted as shown in the block diagram of FIG. 2. In the access control by the control system, the light detector 105 detects the track traversing signal (the tracking error signal). A counter 110 counts the number of traversed tracks on the basis of the track traversing signal. A reference speed generator 111 generates a target speed (a reference speed) based on the number of the remaining tracks.
On the other hand, a speed detector 114 binarizes the track traversing signal to generate a track count pulse, then divides a track pitch by an interval of the track count pulses to obtain a relative moving speed on the tracks. A gain compensator 113 compensates the difference between the relative moving speed and the reference speed by amplification to output a drive signal to the feed motor 107 as the coarse actuator.
According to the conventional method, the access control by the speed control is performed at first, wherein the difference between the relative moving speed and the reference speed is fed back to the feed motor 107 until the detected relative moving speed equals the reference speed. It is found that the detected relative moving speed equals the reference speed when the output of the gain compensator 113, which indicates the difference thereof, becomes 0. When the detected relative moving speed equals the reference speed, a control circuit 119 switches Sw1 and Sw2.
After switching Sw1 and Sw2, the objective lens actuator 106 is controlled by the difference between the relative moving speed and the reference speed, and the feed motor 107 is controlled by the output from a displacement sensor 104 for detecting the amount of shift of the objective lens 102 from the optical axis.
The objective lens actuator 106 is subjected to the speed control, and the feed motor 107 is controlled so as to move in accordance with the displacement of the objective lens 102. Such a control system is constituted to perform acceleration with the maximum capacity in high-speed access in order to shorten the access time, and in low-speed access, to control the coarse and precise actuators so as to cooperate for attaining the precise access.
The above-mentioned constitution, however, essentially needs an expensive sensor for actually detecting the relative displacement of the objective lens, and thus the reduction in the manufacturing cost cannot be attained. In addition, the feed motor and the driving force transmission mechanism is subject to non-linear factors and delay factors such as friction, as described above, and it thus may frequently occur that the displacement of the actuator may not actually attained with use of fine output from the sensor. The access speed may be decreased, at the same time. Further, the non-linear elements of the driving force transmission mechanism may adversely affect the start of access at which the tracking state is transferred to the access state, with the result that some problems occur in which the feed motor does not displace at the start of access.
In general, the objective lens actuator has a higher drive sensitivity and higher response frequency than those of the feed motor. Therefore, in the case where the feed motor is controlled to move in accordance with the movement of the objective lens actuator, it cannot be prevented that the feed motor displaces with a low speed after a considerable period of time during which the objective lens actuator has made a large displacement. The large displacement of the objective lens actuator results in large shifts of the objective lens from the optical axis, and a deterioration of the optical signal.
With the conventional access control method, the feed motor is controlled to move in accordance with the movement of the objective lens actuator in consideration of the above-mentioned limitations of the actuators. However, the response speed of the feed motor is so low that a large shift of the objective lens will inevitably occur.
To sum up, it is difficult with the conventional constitution of the optical disk apparatus to overcome the limitations of the actuators. There is concern that this problem will be more serious in future optical disk apparatus used for higher density disks.
The present invention is developed to solve the above-mentioned problems, and intended to provide a disk apparatus capable of precise and stabilized access and seek control with high speed without increasing the manufacturing cost.
According to the aspects of the present invention, a disk apparatus comprising: information recording/reproducing mechanism which records/reproduces information on a disk having a plurality of information tracks; a precise positioning mechanism which finely displaces the information recording/reproducing mechanism in a radial direction of the disk; a coarse positioning mechanism which positionally displaces the information recording/reproducing mechanism in an entire information recording region in the radial direction of the disk; a speed detector which detects a moving speed of the information recording/reproducing mechanism in the radial direction of the disk in accordance with a signal reproduced by the information recording/reproducing mechanism; a displacement calculator which detects a moving distance of the information recording/reproducing mechanism in the radial direction of the disk in accordance with a signal reproduced by the information recording/reproducing mechanism; a reference speed generator which generates a reference speed used for controlling the drive of the precise positioning mechanism in accordance with the displacement calculated by the displacement calculator; a drive signal generator which generates a drive signal for driving the coarse positioning mechanism in accordance with the displacement calculated by the displacement calculator; a coarse positioning mechanism driving circuit which controls the drive of the coarse positioning mechanism in accordance with the drive signal generated by the drive signal generator; and a precise positioning mechanism driving circuit which controls the drive of the precise positioning mechanism in accordance with a difference between the moving speed detected by the speed detector and the reference speed generated by the reference speed generator.

Apparatus for accessing recording disk by controlling the coarse and precise actuators


A first feature quantity computing unit that computes a first feature quantity representing an average of a plurality of driving loads recorded by a driving load of a fixing section recording unit of an image forming device that records the driving load acquired by a driving load acquiring unit that acquires the driving load, a second feature quantity computing unit that computes a second feature quantity representing a deviation of the plurality of the driving loads, and a diagnosis unit that performs failure diagnosis including estimation of a cause of a failure of the fixing section using the first feature quantity and the second feature quantity are used.

1. Field of the Invention
The present invention relates to a failure diagnosis device and a failure diagnosis method for a failure of an image forming device such as a copy machine, a printer, and a facsimile, particularly, a failure of a fixing section, an image forming device in which the failure is diagnosed by the failure diagnosis device or the failure diagnosis method, and a computer program product comprising a computer-usable medium having computer-readable program codes embodied in the medium for executing the failure diagnosis method.
2. Description of the Related Art
An image forming device such as a copy machine, a printer, and a facsimile includes a number of units or components. When abnormality occurs in the image forming device due to a failure or the end of life of the unit, etc., it is necessary to perform repair or maintenance such as replacement. Some or all functions of the image forming device need to be stopped while the repair is performed. In performing the repair, it may take a long time to find out a cause of abnormality, and thus there is a problem in that a user is inconvenienced because it is impossible to use the image forming device during that time in addition to a net time of repair or the like. This problem also occurs when the maintenance on a portion in which abnormality is likely to occur is performed before abnormality occurs. In order to solve the problem, it is required to diagnose where abnormality of the image forming device occurs or is likely to occur to perform the maintenance, etc., thereby reducing downtime.
In this regard, a technique for estimating a failure portion (for example, see Japanese Patent Application Laid-open No. 06-208265), a technique for extracting a candidate of a failure portion or a portion that is likely to cause a failure (for example, see Japanese Patent Application Laid-open No. 2005-309077), and a technique for determining whether or not a device is in an abnormal state or anticipating an occurrence of a failure in a device (for example, see Japanese Patent Application Laid-open No. 2008-102474) have been suggested.
Meanwhile, as one of constitutions disposed in the image forming device, a fixing section has a larger number of components in general and is relatively higher in cost than other constitutions. Since the fixing section has a larger number of components, various causes may be considered as a cause of its trouble or its failure. Therefore, the same problem as the problem described above, for example, a problem in that a time taken for maintenance tends to become longer and unnecessary maintenance may be performed for a portion different from a cause is exactly applied to the fixing section. Consequently, similarly, in order to solve the problem in the fixing section, it is important to diagnose where abnormality of the fixing section occurs or is likely to occur to perform the maintenance, thereby reducing downtime.
In this regard, the applicant previously suggested a failure diagnosis device that performs failure diagnosis of a fixing section disposed in an image forming device including estimation of a cause of trouble related to a paper transport time in the fixing section in Japanese Patent Application No. 2009-163382.
However, since trouble in the fixing section is not caused only in connection with the paper transport time, it is required to additionally suggest a technique for being capable of dealing with other causes of trouble.

Failure diagnosis device, failure diagnosis method, image forming device, and recording medium


A file recovery logic implemented within a data processing system is disclosed that recovers data from a file on a write once read many (WORM) medium when the file cannot be accessed due to the damage to both the hash and hierarchical directory entries. The file recovery logic controls access to the WORM medium and also access to a target medium via optical devices that enable read from the WORM medium and write to the target medium. The file recovery logic scans each logical sector of the WORM medium""s data surface and identifies a location of a data header sector that corresponds to the unaccessible file. In the preferred embodiment, identification of the data header sector is completed by analyzing only the first few bytes of the sector. Upon location of the header sector, a new file is opened in a target medium and the data from contiguous sectors on the WORM medium beginning at the data header sector are retrieved and written to the new file on the target medium. The scanning, retrieving, and writing continue until a next header, a tail, or a blank sector is encountered, or the last sector on the medium""s scanning range is reached. The new file is then stored on the target medium with the data from the unaccessible file, and thus, the previously unaccessible data is made available.

1. Technical Field
The present invention relates in general to computer storage devices and, in particular, to an optical Write-Once Read-Many (WORM) medium. Still more particularly, the present invention relates to a method and program product for recovering lost data from an optical WORM medium.
2. Description of the Related Art
Sensitive data, such as a customer""s banking records, legal documents, etc., are often permanently stored in a medium that permits access for later viewing of the stored data but prevents tampering and/or erasure of the data. Common examples of such a medium are the optical write-once read-many (WORM) medium and the compact disc recordable medium (CD-ROM). Present implementation of the WORM medium utilizes an optical scanner, i.e., a laser, to write and read the data, stored as files on the medium.
As the name implies, a WORM medium enables data to be written on the medium once and accessed many times thereafter. The data files are identified and access via a hash and/or hierarchical directory entry stored on the medium. Data stored on a WORM medium are considered secure because the data can not be erased from the medium or easily corrupted by an external source. The data are thus expected to be available and accessible for as long as the medium is available, and hence the WORM medium provides reliable data storage for lifetime documents.
Typically, the data in a WORM medium are accessed via one of two directory entries, a hash or a hierarchical entry. Both hash and hierarchical entries are fundamental to the data they are associated with, and both provide a backup function for each other. The hash and hierarchical entries are created at the same time the data is written on the WORM medium. Depending upon the access method utilized, one of the two entries is utilized to retrieve the data from the medium during later access.
The protection provided by the WORM medium, however, does not always prevent files from becoming damaged. Many factors such as power failure, device problems, software problems, user""s improper operation of the device, etc., may cause damage to the stored data. Also, failure of the WORM medium may occur for a number of reasons, including calibration track damage, electric static discharge damage, or contaminants embedded on the medium. When damage to the files on the medium occurs, some of the data stored in the medium will no longer be accessible by users with the normal data retrieval procedures that utilize a data retrieval application.
In some instances, the damage may be permanent, (e.g., physical damage to the media, raw data area (sectors) damage, etc.) and the data will never be recovered. However, most of the time data retrieval problems encountered with a WORM medium is caused by damage to a directory entry, which prevents the associated data from being accessible by referencing that directory entry. Directory entry damage may be attributed to the fact that, with most file system design, the directory entry sector on the medium is scanned very often compared to the area on which the data is stored, leading to excessive wear and eventual damage. Thus, having a damaged data area is not uncommon for a file stored on a WORM medium.
Because the directory entries are initially stored in pairs, fixing a damaged directory entry of a file on a WORM medium is usually not a difficult task when the backup directory entry is available. Repairing a bad directory entry for a file using the good backup entry has become a standardized procedure.
In certain instances, however, both the hash and hierarchical file entries of a file are damaged or destroyed, and the user can no longer retrieve the file from the WORM medium although the file""s data are saved permanently on the WORM medium. Presently, there is no generally applicable way to recover a file if both directory entries are damaged. The situation may be especially critical for a file owner when there is no other source of the data except that on the WORM medium.
A file recovery logic implemented within a data processing system is disclosed that recovers data from a file on a write once read many (WORM) medium when the file cannot be accessed due to the damage to both the hash and hierarchical directory entries. The file recovery logic controls access to the WORM medium and also access to a target medium via optical devices that enable read from the WORM medium and write to the target medium. The file recovery logic scans each logical sector of the WORM medium""s data surface and identifies a location of a data header sector that corresponds to the unaccessible file. In the preferred embodiment, identification of the data header sector is completed by analyzing only the first few bytes of the sector. Upon location of the header sector, a new file is opened in a target medium and the data from contiguous sectors on the WORM medium beginning at the data header sector are retrieved and written to the new file on the target medium. The scanning, retrieving, and writing continue until a next header, a tail, or a blank sector is encountered, or the last sector on the medium""s scanning range is reached. The new file is then stored on the target medium with the data from the unaccessible file, and thus, the previously unaccessible data is made available.
All objects, features, and advantages of the present invention will become apparent in the following detailed written description.

Method and system for recovering data from an optical write once read many (WORM) medium with both directory entries damaged

International Business Machines Corporation


The present invention relates to a pneumatic rubber tire having an integral innerliner of a rubber composition comprised of butyl rubber and/or halogenated butyl rubber and low molecular weight trans 1,4-polybutadiene rubber, wherein said rubber composition may also contain a minor amount of at least one additional, sulfur curable, elastomer.

The present invention relates to a pneumatic rubber tire having an integral innerliner of a rubber composition comprised of butyl rubber and/or halogenated butyl rubber and low molecular weight trans 1,4-polybutadiene rubber, wherein said rubber composition may also contain a minor amount of at least one additional, sulfur curable, elastomer.
U.S. Pat. No. 6,024,146 relates to a tire having an integral innerliner comprised of bromobutyl rubber, trans 1,4-polybutadiene rubber and, optionally, a minor amount of sulfur curable rubber.
Although the trans 1,4-polybutadiene rubber in U.S. Pat. No. 6,024,146 is broadly referred to, the specification specifically describes a high molecular weight trans 1,4-polybutadiene rubber having a preferable number average molecular weight value (Mn) measured by GPC (gel permeation chromatograph analysis) of greater than 130,000, although its first claim does not contain a molecular weight restriction. The specification observes that use of the high molecular weight trans 1,4-polybutadiene rubber in the tire innerliner rubber composition beneficially increases the green strength of the innerliner composition. Preparation of the trans 1,4-polybutadiene is recited as being prepared by batch polymerizing 1,3-butadiene in an organic solvent in the presence of cobalt octoate and triethyl aluminum as a catalyst system with a para alkyl substituted phenol as a catalyst modifier.
For this invention, a low molecular weight trans 1,4-polybutadiene rubber is prescribed having a number average molecular weight value (Mn) measured by GPC in a range of from 10,000 to 50,000 which is spaced apart from said high molecular weight trans 1,4-polybutadiene described in U.S. Pat. No. 6,024,146 by at least 80,000 molecular weight units and is thereby a significant and substantial departure from use of the aforesaid high molecular weight trans 1,4-polybutadiene rubber.
The low molecular weight trans 1,4-polybutadiene rubber for this invention may be prepared by polymerizing 1,3-butadiene monomer in an organic solvent (e.g. hexane) with a combination of triethylaluminum, barium thymolate and n-butyllithium (n-BuLi) as a catalyst complex system instead of the cobalt octoate and triethylaluminum based catalyst system utilized in said U.S. Pat. No. 6,024,146.
Historically, the inner surface of a pneumatic tire is typically comprised of a layer of a rubber composition designed to prevent or retard the permeation of air and moisture into the carcass from the tire""s inner air chamber. It is often referred to as an innerliner. Innerliners have also been used for many years in tubeless pneumatic vehicle tires to retard or prevent the escape of air used to inflate the tire, thereby maintaining tire pressure. Rubbers, such as butyl rubber and halogenated butyl rubber, often referred to as halobutyl rubber, as well as blends thereof, are often used for such tire innerliners which are relatively impermeable to air.
Historically, the tire innerliner itself is normally prepared by conventional calendering or milling techniques to form a strip of uncured rubber composition of appropriate width which is sometimes referred to as a gum strip. Typically, the gum strip is the first element of the tire applied to a tire building drum, over and around which the remainder of the tire is built. When the tire is cured, the innerliner becomes an integral, co-cured, part of the tire. Tire innerliners and their methods of preparation are well known to those having skill in such art.
The use of the prescribed low molecular weight trans 1,4-polybutadiene rubber for this invention is considered herein to be significant to reduce cost of an associated rubber composition for a tire innerliner where a portion of halobutyl rubber content is replaced, while significantly maintaining a low strain stiffness property and providing a desirable low air permeability. This is considered herein to be significant because, in contrast, while a relatively high molecular weight cis 1,4-polybutadiene rubber would be expected to similarly reduce rubber innerliner rubber composition cost, such higher molecular weight polybutadiene would be more difficult to process because of its higher Mooney viscosity and would have a much higher air permeability property.
In the description of this invention, the term xe2x80x9cphrxe2x80x9d means parts by weight of an ingredient per 100 parts by weight of elastomer in a rubber composition unless otherwise indicated. The terms xe2x80x9crubberxe2x80x9d and xe2x80x9celastomerxe2x80x9d are used interchangeably unless otherwise indicated. The terms xe2x80x9ccurexe2x80x9d and xe2x80x9cvulcanizexe2x80x9d are used interchangeably unless otherwise indicated. The terms xe2x80x9crubber compositionxe2x80x9d and xe2x80x9crubber compoundxe2x80x9d are used interchangeably unless otherwise indicated.
In accordance with this invention a tire is provided having an innerliner rubber composition comprised of, based upon 100 parts of rubber (phr);
(A) from about 70 to about 98 phr of rubber selected from the group consisting of butyl rubber, chlorobutyl rubber, bromobutyl rubber and mixtures thereof;
(B) about 2 to 30 phr of a trans 1,4-polybutadiene rubber having a number average molecular weight (Mn) (as measured by GPC, or gel permeation chromatograph) of not greater than 50,000 and desirably in a range of from about 10,000 to about 50,000, a trans 1,4-content in a range of about 80 to about 85 percent, and a vinyl content of less than 5 percent;
(C) from zero to 30, alternatively from about 5 to about 15, phr of at least one elastomer selected from acrylonitrile/butadiene copolymer, styrene/butadiene copolymer, cis 1,4-polyisoprene natural and/or synthetic rubber and mixtures thereof.
A significant aspect of utilization of a low molecular weight trans 1,4-polybutadiene for the tire innerliner of this invention is improved processing with a substantially maintained low strain stiffness with a relatively small increase in air permeability.
While the trans 1,4-polybutadiene of aforesaid U.S. Pat. No. 6,024,146 is of a relatively high crystallinity, a significant aspect of this invention is the use of a low molecular weight trans 1,4-polybutadiene also of relatively high crystallinity to obtain the aforesaid rubber composition processing, physical property(ies) and suitable air permeability.
This is in contrast with using a low molecular weight trans 1,4-polybutadiene of relatively low or no crystallinity which would have much higher air permeability.
Thus a significant aspect of this invention is the combination of both low molecular weight and high crystallinity for the trans 1,4-polybutadiene for the tire innerliner rubber composition
A significance of relatively high crystallinity of the low molecular weight trans 1,4-polybutadiene is considered herein as being advantageous for maintaining low air permeability and low strain cured stiffness while providing improved processing.
The relatively high crystallinity aspect of the low molecular weight trans 1,4-polybutadiene, as measured by differential scanning calorimeter (DSC) at a heating rate of 10xc2x0 C. per minute, is evidenced by two relatively sharp melting point peaks, namely a first peak at about 36xc2x0 C. (about 30xc2x0 C. to about 40xc2x0 C.) and a second peak at about 44xc2x0 C. (about 40xc2x0 C. to about 50xc2x0 C.). It also has a Tg (glass transition temperature determined at a temperature rise of about 10xc2x0 C.) of about xe2x88x9291xc2x0 C. In contrast, the high molecular weight trans 1,4-polybutadiene has two melting point peaks with a first peak in a the range of 35xc2x0 C. to about 45xc2x0 C. and a second peak in a range of about 55xc2x0 C. to about 65xc2x0 C.
In general, the low molecular weight trans 1,4-polybutadiene polymer has a microstructure composed of a trans 1,4-content in a range of about 80 to about 85 percent, a vinyl 1,2-content in a range of about 2 to about 5 percent with the remainder being primarily of a cis 1,4-content in contrast to a vinyl content value of from 5 to 20 weight percent and a cis 1,4-content of from 2 to 15 weight percent of the high molecular weigh trans 1,4-polybutadiene polymer prescribed by U.S. Pat. No. 6,024,146.
Other than the presence of the required low molecular weight trans 1,4-polybutadiene, the remaining rubber components in the rubber compound for use as an innerliner may vary depending on the desired properties for the tire innerliner. For example, based on 100 parts by weight of total rubber, from about 70 to 98 phr is a xe2x80x9cbutyl-typexe2x80x9d rubber selected from the group consisting of butyl rubber, chlorobutyl rubber, bromobutyl rubber and mixtures thereof may be used. Desirably, the amount of xe2x80x9cbutyl-typexe2x80x9d rubber may range from about 85 to 95 phr. Usually, the desired xe2x80x9cbutyl-typexe2x80x9d rubber is brominated butyl rubber as bromobutyl rubber. In addition to the butyl type rubber, the rubber composition may contain from about zero to 30, alternately about 0 to about 15 phr of a non-butyl type, sulfur curable, elastomer selected from at least one of acrylonitrile/butadiene copolymer, styrene/butadiene copolymer, natural rubber and mixtures thereof A desirability of using a non-butyl type, sulfur curable, elastomer may vary, depending somewhat on the relative cost of the elastomer and the cured properties desired. A desirable non-butyl type rubber is considered herein to be an acrylonitrile/butadiene copolymer.
Butyl rubber is conventionally described as a copolymer of isobutylene and isoprene wherein the copolymer contains from about 2 to about 6 weight percent units derived from isoprene (and thus from about 94 to about 99 weight percent units derived from isobutylene). A halobutyl rubber is a butyl rubber which has been halogenated, usually with bromine or chlorine. Thus such halobutyl rubber is typically either bromobutyl rubber or chlorobutyl rubber. Such butyl rubber and halobutyl rubber are well known to those having skill in such art.
The rubber compound containing the low molecular weight trans 1,4-polybutadiene may be prepared by blending with various conventional rubber compounding ingredients, depending somewhat upon innerliner properties desired. Conventional ingredients commonly used in rubber vulcanizates are, for example, carbon black, tackifier resins, processing aids, talc, clay, mica, silica, antioxidants, antiozonants, stearic acid, activators, waxes, oils and peptizing agents. As known to those skilled in the art, depending on the intended use of the sulfur vulcanized rubber, certain additives mentioned above are commonly used in conventional amounts. Typical additions of carbon black comprise from about 10 to 100 parts by weight based on 100 parts by weight of rubber (phr), preferably 40 to 70 phr. Typical amounts of talc, clay, mica, silica and calcium carbonate may range from about 2 to 25 phr. Typical amounts of tackifier resins comprise about 2 to 10 phr. Typical amounts of processing aids comprise about 1 to 15 phr. Typical amounts of antioxidant comprise 1 to 5 phr. Typical amounts of stearic acid comprise 0.50 to about 2 phr. Typical amounts of zinc oxide comprise 1 to 5 phr. Typical amounts of oils comprise 2 to 30 phr. The presence and relative amounts of the above additives are not an aspect of the present invention.
The vulcanization of the compound for use as an innerliner is conducted in the presence of a sulfur vulcanizing agent. Examples of suitable sulfur vulcanizing agents include elemental sulfur (free sulfur) or sulfur donating vulcanizing agents, for example, an amine disulfide, polymeric disulfide or sulfur olefin adducts. As known to those skilled in the art, sulfur vulcanizing agents are used in an amount ranging from about 0.2 to 5.0 phr with a range of from about 0.5 to 3.0 being preferred.
Accelerators are used to control the time and/or temperature required for vulcanization and to improve the properties of the vulcanizate. A single accelerator system may be used, i.e., primary accelerator in conventional amounts ranging from about 0.5 to 3.0 phr. In the alternative, combinations of 2 or more accelerators may be used which may consist of a primary accelerator which is generally used in the larger amount (0.3 to 3.0 phr), and a secondary accelerator which is generally used in smaller amounts (0.05 to 10 phr) in order to activate and to improve the properties of the vulcanizate. Combinations of these accelerators have been known to produce a synergistic effect on the final properties and are somewhat better than those produced by either accelerator alone. In addition, delayed action accelerators may be used which are not effected by normal processing temperatures but produce satisfactory cures at ordinary vulcanization temperatures. Suitable types of accelerators that may be used are amines, disulfides, guanidines, thioureas, thiazoles, thiurams, sulfenamides, dithiocarbamate and xanthates. Preferably, the primary accelerator is a disulfide or sulfenamide.
In practice the rubber compound is formed into a gum strip. As known to those skilled in the art, a gum strip is produced by a press or passing a rubber compound through a mill, calender, multi-head extruder or other suitable means. Preferably, the gum strip is produced by a calender because greater uniformity is believed to be provided. The uncured gum strip is then constructed as an inner surface (exposed inside surface) of an uncured rubber tire structure, also known as the carcass. The innerliner is then sulfur co-cured with the tire carcass during the tire curing operation under conditions of heat and pressure. The innerliner rubber gum strip may have a thickness, for example, in a range of about 0.04 to about 0.4 centimeters, depending somewhat upon the particular associated tire.
Vulcanization of the tire of the present invention is generally carried out at temperatures of between about 100xc2x0 C. and 200xc2x0 C. Usually the vulcanization is conducted at temperatures ranging from about 110xc2x0 C. to 180xc2x0 C. Any of the usual vulcanization processes may be used such as heating in a press or mold, heating with superheated steam or hot salt or in a salt bath. Preferably, the heating is accomplished in a press or mold in a method known to those skilled in the art of tire curing.
As a result of this vulcanization, the innerliner becomes an integral part of the tire by being co-cured therewith. The innerliner of the present invention, as mentioned above, may have an uncured gum thickness in the range of from about 0.04 to 0.4 centimeters. Preferably, the innerliner has an uncured gum thickness in the range of from about 0.08 to about 0.20 centimeters for passenger tires, although the innerliner can be considerably thicker for truck tire. For example, as a cured innerliner, the innerliner may have a thickness ranging from about 0.02 to about 0.35 centimeters with an innerliner thickness in a range of about 0.04 to about 0.15 cm for passenger tires and considerably thicker for truck tire and light truck tire applications.
The pneumatic tire with the integral innerliner may be constructed in the form of a passenger tire, truck tire, or other type of bias or radial pneumatic tire.
The following examples are presented in order to illustrate but not limit the present invention. The parts and percentages are by weight unless otherwise noted.

Pneumatic tire having an innerliner of a rubber composition which contains a low molecular weight trans 1,4-polybutadiene rubber


A battery can 2 is composed of a can body 3 having a concave portion 31 for accommodating an electrode body 5, and a metal cover 4 for sealing an opening end of the concave portion 31 of the can body 3. The can body 3 is formed in a plate shape by subjecting a metal plate to shallow drawing. A flange 32 is provided at a peripheral edge portion of the opening end of the can body 3, which is bonded to be integrated with the metal cover 4 to keep an air-tight and liquid-tight state in the concave portion 31.

Batteries used as power sources of electronic equipment have, for example, a cylindrical shape or a prismatic shape. In a cylindrical battery, a metal can deep-drawn to a cylindrical shape (cylindrical drawing) is used, and in a prismatic battery, a metal can deep-drawn to a prismatic shape (prismatic drawing) is used.
On the other hand, in small portable electronic equipment such as a portable information terminal requiring thinness, a relatively thin battery is used. This kind of thin battery is classified into the following types.
(1) A thin battery in which a metal can (deep-drawn can) subjected to the above-mentioned deep-drawing is used, and a metal cover is fitted to an opening of the metal can, followed by welding (e.g., see a conventional prismatic non-aqueous electrolyte secondary battery described in JP 11(1999)-185820 A).
(2) A thin battery using a laminate, in which a metal foil such as an aluminum foil and resin are stacked, as an outer member so as to set the entire thickness small.
(3) A thin battery in which a metal can (shallow-drawn can) subjected to shallow-drawing, such as a lunch box, is used, and a metal cover is fitted to an opening of the metal can, followed by welding (e.g., see a non-aqueous electrolyte solution secondary battery described in JP 11(1999)-185820 A).
In recent years, as seen from the spread of the above-mentioned portable information terminal, there is a strong demand for small and light-weight electronic equipment. Along with this, there also is an increasing demand for thinness of a battery to be mounted on the electronic equipment.
However, a conventional thin battery has a prismatic shape or an elliptically cylindrical shape. Therefore, in order to attach such a battery to equipment or a resin pack (battery pack) to be mounted on the equipment, it is necessary to provide a battery chamber or fix the battery at a predetermined position with a double-faced tape or an adhesive. When the battery chamber is provided, the thickness of the equipment is increased by the thickness of the battery chamber. When the battery is fixed with an adhesive, an increase in thickness of the equipment can be avoided; however, it is difficult to separate the battery for disposal, which is likely to have detrimental effects in modern time as recycling is important.
Furthermore, the conventional thin battery configuration as described in the above (1) to (3) cannot sufficiently meet the demand for further thinness. Alternatively, even if a battery can be made thinner, its strength may not be sufficient, inconvenience is likely to occur in the course of production, it is not easy to set the battery on equipment, etc. Thus, various problems occur.
More specifically, in the battery described in the above (1), a deep-drawn can is used as a battery can, so that there is a predetermined limit to the size to be formed. For example, the thinnest can has a thickness of about 3 mm, and it is impossible or very difficult to obtain a can with a thickness of about 3 mm or less by the current deep-drawing technique. Therefore, in order to obtain such a thin battery can, a stacked material such as a laminate as described above cannot help being used as a battery outer member. In this case, although the thinness of the laminate can be ensured, the strength of the laminate with respect to sticking and bending is smaller than that of a metal can, and furthermore, there is a possibility of swelling of a battery and leakage of liquid.
Furthermore, even if a metal can with a thickness of 3 mm or less can be formed, a deep-drawn can has the following problems.
(A) As the thickness of a metal can is decreased, the width of an opening thereof (opening width in a thickness direction of the can) is decreased, whereby it becomes difficult to insert an electrode in the metal can.
(B) Terminals are attached to attachment holes provided at a metal cover for sealing an opening of a can, via an insulating packing (gasket) made of resin. When the width of the opening becomes narrow, the insulating packing is placed doser to an opening edge. Therefore, when the metal cover is fitted to the opening and bonded thereto by laser welding or the like, the insulating packing is likely to be melted due to welding heat between the metal cover and the can.
(C) For deep-drawing, only an extendable material having a required extensibility is used. Therefore, the kind of metal to be formed is limited, and the hardness of metal to be formed is small. Therefore, a deep-drawn can is weak to the swelling of a battery. Thus, materials that have a large hardness (i.e., that are hard), light weight and strength cannot be used even if desired.
On the other hand, a battery using a shallow-drawn can described in the above (3), more specifically, a battery as described in, for example, JP 11(1999)-185820 A can avoid most of the above-mentioned problems in the battery using a deep-drawn can. However, such a battery also has the following problems.
(a) For example, a peripheral edge of the maximum opening of a can is provided with a cover having the same size as that of the peripheral edge, and the vicinity of the peripheral edge of the maximum opening is welded. Therefore, welding heat is likely to be transmitted to an electrode body (electrode element) in a can and components placed near the welded portion, which may have thermal influence.
(b) In the case where a cover is attached by crimping an outer periphery of the cover and the peripheral edge of an opening (i.e., by seaming), instead of welding, productivity is decreased compared with the case using welding, and there may be a possibility of leakage of liquid from the connected portion between the outer periphery of the cover and the peripheral edge of the opening.
(c) A battery has a simple prismatic shape although it is thin. Therefore, in order to provide a protection circuit required in a secondary battery, it is necessary to separately keep or provide a space for the protection circuit or a base for attachment thereof.
(d) It is necessary to provide a battery chamber for attaching a battery to equipment or a resin pack (battery pack) or to fix a battery at a predetermined position with a double-faced tape or an adhesive. Thus, there are problems similar to those in the case of a prismatic or cylindrical thin battery as described above.

Battery comprising a flange formed at a peripheral edge and a protection circuit attached to the flange


In a vehicular control apparatus mounted on a vehicle including an internal combustion engine, a rotating electrical machine, and a storage device that is supplied with a power from the rotating electrical machine, the vehicle can be decelerated through stoppage of injection of fuel into the internal combustion engine and regenerative braking by the rotating electrical machine. The vehicular control apparatus controls the vehicle such that a remaining capacity in the storage device becomes lower when a catalyst temperature of the internal combustion engine is high than when the catalyst temperature of the internal combustion engine is low.

1. Field of the Invention
The invention relates to the control of a hybrid vehicle that is equipped with an internal combustion engine and a rotating electrical machine as motive energy sources.
2. Description of Related Art
There is known a hybrid vehicle that is equipped with an engine and a rotating electrical machine as motive energy sources. In such a hybrid vehicle, a deceleration force may be generated by stopping the supply of fuel to an engine (fuel cut) in decelerating the vehicle. However, when this fuel cut is performed with a three-way catalyst, which is used to purify exhaust gas, at high temperatures, the atmosphere around the catalyst may become excessively rich in oxygen (lean) to promote a deterioration in the catalyst. Thus, it is desirable to reduce the frequency of the performance of fuel cut by decelerating the vehicle through regenerative braking.
For example, according to what is disclosed in Japanese Patent Application Publication No. 2009-051466 (JP-A-2009-051466), in a vehicle that is controlled such that a remaining capacity of a storage device (which will be referred to also as an SOC in the following description) falls within a control range defined by a control upper limit and a control lower limit, the control upper limit of the SOC is raised to absorb a power generated through regenerative braking when the SOC is high and a deterioration in a catalyst is apprehended.
However, when the SOC of the storage device is increased by raising the control upper limit of the SOC as described above, the life of the storage device may be shortened through overcharge. A control apparatus disclosed in the aforementioned publication does not take this problem into account and hence cannot offer a solution.

Vehicular control apparatus and vehicular control method


A vehicle interior lighting system includes: a designed cover 10 attached to a ceiling wall in an inside of a vehicle compartment; and a light source unit 20 arranged in the rear of the designed cover. In this system, a light beam emitted from an emission port 25 of the light source unit illuminates the inside of the vehicle compartment through two irradiation holes 15 for spot illumination, which are provided in the designed cover. A light guide 50 is arranged between the emission port 25 of the light source unit and the two irradiation holes 15 of the designed cover. The light guide 50 is configured to divide the light beam emitted from the light source unit into two directions, and to guide the thus-divided light beams to the respective irradiation holes.

1. Field of the Invention
The present invention relates to a vehicle interior lighting system which is installed in the ceiling of a vehicle compartment.
2. Description of the Related Art
FIG. 1 shows a conventional example of the vehicle interior lighting system which is installed in the ceiling of the compartment (see Japanese Patent Application Laid-Open No. 2003-175765).
This vehicle interior lighting system 200 includes: a main illuminator 210 configured to illuminate a wide area in the compartment; two spot illuminators 220 each configured to illuminate a narrow area in the compartment; and a switch 230, which are provided to a designed cover 201 attached to the ceiling wall of a vehicle. The main illuminator 210 is provided with multiple LEDs 211 functioning as a light source and an outer lens 212. Each spot illuminator 220 is provided with an LED (not illustrated) and an outer lens 222.
In the conventional vehicle interior lighting system 200, each of the illuminators 210, 220 and 220 is equipped with at least one LED. This increases the number of parts, thus causing weight and cost increase. Furthermore, the two spot illuminators 220 tend to exhibit unevenness in color and illuminance even if two LEDs with the same color are used for the two spot illuminators 220, because the two LEDs vary from each other. This may cause difference in appearance among illuminated areas depending on which LED to be used.


A method for making a plurality of colored sportcards comprising the steps of forming a master panel with a matrix of borders, each associated with a window area; cutting each window area into a border opening; pasting a photograph behind each window opening; making a colored photocopy of the master panel and the colored photographs; pasting a back panel on the rear of the photocopied panel having indicia related to each of the images within the photocopied window openings; and then cutting the photocopied panel and the back panel to as many sub panels as there are photocopied windows to form a plurality of sportscards. The process is repeated so that each individual photograph is made into as many sportscards as desired.

Sportscards are commonly made for popular athletes, such as baseball players and the like. They are usually about 2 1/2 inches wide and 3 1/2 inches tall, printed on a relatively stiff cardstock. Commercially available sportscards made for professional athletes are relatively inexpensive because they are printed in substantial volumes, but using relatively expensive printing methods.
There is a market for sportscards for amateur athletes. Conventional sportscard printing methods are not suitable for such a market because of the low volume. For example, an amateur athlete may only need 10-20 cards.


The disclosed invention provides system and method for whole word conversion of text in an image. The system and method may convert the text in the image into Unicode strings. The system and method utilizes comparable features of word segments that are extracted from the text in the image. The comparable features of the word segments are created by mirroring comparable features of word templates stored in a conversion database. Word templates in the database are filtered by comparing the comparable features of the word segments with comparable features of the word templates in the database. The word segments are correlated to matching word candidates. Word confusion networks are constructed with the matching word candidates, and the word confusion networks are evaluated to output matching words for the word segments. This system and method reduce the search space in the database improving search efficiency.

Document images may contain information in a variety of languages. The contents of the document images are images that are not recognized as language characters. Organization may need to extract information from the document images. However, the document images are not able to be searchable by using typical information retrieval techniques. In order to solve this issue, document image-to-text technologies have been developed for a variety of languages. However, the document image-to-text techniques for script-based languages such as Arabic, Persian, Pashto, Urdu, and Thai have been challenges. For example, an image-to-text technique that can be used for Arabic language may not be applicable for other script-based language such as Persian, Urdu, Pashto, or Hindi. Known image-to-text techniques for the script-based languages often produce inaccurate output due to their inability to utilize accurate image comparison techniques at acceptable performance levels.
One of the image-to-text techniques, optical word recognition (OWR), is described in U.S. Pat. No. 6,741,743 ("the '743 patent") and U.S. Pat. No. 7,574,050 ("the '050 patent"). OWR technology applies an optical correlation approach to the analysis of text and other information in imaged documents. OWR provides an analysis capability that to date has primarily been used for language identification, logo detection, and signature identification in imaged documents. The concept, general approach, and challenges of OWR are described in the '050 patent.
In the descriptions, elements of the existing approach as described in the patents mentioned above will be referred to as OWR, and elements of the disclosed invention will be described as optical word conversion (OWC). One significant advantage that the OWC-based approach has over other techniques is that the OWC technique is based on machine learning techniques. The development of each additional language will not require significant effort beyond that needed for the first structurally similar language, making maximum use of data-driven machine learning techniques.
Although the development and testing work done here focuses on English and Pashto, there was great care taken to prevent language-specific elements from shaping key elements of the OWC approach. Beyond the fully automated machine learning database construction process, the language-specific adaptation, which must be made such as punctuation convention specification, selection of relevant fonts, is minimal.

System and method for whole word conversion of text in image