A communication system includes an on-board unit adapted to a vehicle-vehicle communication and roadside equipment 10 performing a roadside-vehicle communication. In communications in service channels of the vehicle-vehicle communication, one reception-only service channel in which the on-board unit only performs a reception operation is provided for a plurality of the service channels and communications in the reception-only service channel is performed at the same frequency as that of the control channels of the roadside-vehicle communication. When the vehicle-vehicle communication is performed, the on-board unit performs switching to the roadside-vehicle communication in response to detection of reception in the reception-only service channel of a radio signal transmitted from the roadside equipment 10 in a control channel of the roadside-vehicle communication.

In the field of the intelligent transport system (ITS), WAVE (wireless access in vehicular environment) has been proposed as a communication standard for offering various services to an on-board unit (or a vehicle mounting the on-board unit). WAVE, which is a modification of the wireless LAN standard, IEEE 802.11, for a mobile communication, uses IEEE 802.11p in layer 1 (physical layer) and layer 2 (data link layer). One feature of WAVE is that a distributed coordination function (DCF), in which transmission opportunity is equally allocated to each terminal, is performed. In detail, each communication frame is divided into a plurality of time slots each called "channel" in WAVE. Each communication frame includes one control channel and at least one service channel. Broadcasting is performed in a control channel and a communication for transmitting data to a specific destination is performed in a service channel. A source communication terminal desiring data transmission specifies a destination communication terminal and a service channel to be used for the data transmission in a control channel. The destination communication terminal receives data from the source communication terminal in the specified service channel. Multiple services are time-divisionally offered in parallel by alternately repeating communications in the control channels and communications in the service channels. It should be noted that patent literature 1 (Japanese patent application publication No. 2010-239607 A) discloses a technique related to WAVE.
FIG. 1, which is an illustration schematically illustrating one example of communications in accordance with WAVE, illustrates one example of a communication procedure for offering two services A and B to communication terminal #1. In FIG. 1, communication terminal #2 is a communication terminal which offers service A and communication terminal #3 is a communication terminal which offers service B.
Discussed below is an example in which communication terminal #1 transmits data indicating to perform communications for service A and specifying a service channel in which a response is to be done, in a control channel of communication frame #k through broadcasting. Communication terminal #2, which offers service A, transmits data to communication terminal #1 in a service channel in response to the data transmitted by communication terminal #1. Although communication terminal #2 transmits the data in the next service channel, that is, the service channel of communication frame #k in the example of FIG. 1, communication terminal #2 may transmit the data in a service channel other than in the next service channel. Communication terminal #3, with which no communication is requested, does not issue a response even when receiving the data from communication terminal #1 through broadcasting. Further discussed below is the case when communication terminal #1 transmits data indicating to perform communications for service B and specifying a service channel in which a response is to be done, in a control channel of communication frame #k+1 through broadcasting. In this case, communication terminal #3, which offers service B, transmits data to communication terminal #1 in a service channel in response to the data transmitted by communication terminal #1. Multiple services are offered to communication terminal #1 in this way.
One issue is that, in order to achieve switching between multiple services, the respective services are required to use a common frequency for communications in the control channels, whereas the use of the common frequency may cause radio-wave interference due to multipath phasing and overlapping of the communicable regions of antennas, when multiple communication terminals performs broadcasting in a control channel at the same time. The occurrence of radio-wave interference may cause a failure in data communications in a control channel and resultingly cause a failure of switching between services.
FIG. 2 is a diagram illustrating an example of occurrence of radio-wave interference in offering a vehicle-vehicle communication service and a roadside-vehicle communication service to an on-board unit 102. As illustrated in FIG. 2, a gantry 113 is disposed across a road 111, and roadside communication devices 101-1 to 101-4 are respectively disposed for respective lanes 112 on the gantry 113. An on-board unit 102, which is mounted on a vehicle 103, functions as a mobile station moving with the vehicle 103. The numerals 104-1 to 104-4 respectively denote the communicable regions of the roadside communication devices 101-1 to 101-4 and the numeral 105 denotes the communicable region of the on-board unit 102.
Discussed below is the case when an on-board unit 102 which has been performing a vehicle-vehicle communication with another on-board unit (not illustrated) enters any of the communicable regions of the roadside communication devices 101-1 to 101-4 and it has become a situation to start a roadside-vehicle communication between the on-board unit 102 and the roadside communication devices 101-1 to 101-4. In other words, there arises a necessity of switching the on-board unit 102 from the state of performing the vehicle-vehicle communication to the state of performing the roadside-vehicle communication. Such situation may occur, for example, when the roadside communication devices 101-1 to 101-4 are used in an electronic toll collection (ETC) system and it is necessary to communicate with the roadside communication devices 101-1 to 101-4 for toll charging.
In this case, radio-wave interference may occur, since the communicable regions 104-1 to 104-4 of the roadside communication devices 101-1 to 101-4 overlap the communicable region 105 of the on-board unit 102. In FIG. 2, the region in which radio-wave interference may occur is denoted by the numeral 106.
FIG. 3 is a conceptual illustration illustrating an example in which a communication in a control channel results in failure due to radio-wave interference and switching from the vehicle-vehicle communication to the roadside-vehicle communication thereby results in failure. In the operation illustrated in FIG. 3, control channels (C-CHs) of the same frequency are used for both of the vehicle-vehicle communication and the roadside-vehicle communication. It should be noted that, in FIG. 3, service channel #1 (S-CH#1) is used for the roadside-vehicle communication (communications between the on-board unit 102 and the roadside communication devices 101-1 to 101-4). Service channel #2 (S-CH#2) is, on the other hand, used for the vehicle-vehicle communication (communications between the on-board unit 102 and another on-board unit (not illustrated)).
The roadside communication devices 101-2 and 101-3 try to transmit data to request communications using the service channel #1 to the on-board unit 102 through broadcasting in a control channel. In the meantime, the on-board unit 102 may try to transmit data for the vehicle-vehicle communication to another on-board unit through broadcasting in a control channel of the same frequency. In this case, the on-board unit 102 may fail in reception of data transmitted from the roadside communication devices 101-2 and 101-3 in a control channel due to radio-frequency interference. This may result in that service channels #2 (S-CH#2) are continuously used by the on-board unit 102 and the service channels used by the on-board unit 102 are not switched to service channels #1, that is, switching from the vehicle-vehicle communication to the roadside-vehicle communication results in failure.
From the background described above, there is a need for providing a technology for performing switching between multiple services with radio-wave interference suppressed.
It should be noted that patent literature 2 (Japanese patent application publication No. 2000-165314 A) discloses a technique, which may relate to the present invention, for providing a vehicle-vehicle communication scheme for performing communications between mobile stations without causing disturbance on a roadside-vehicle communication.

Vehicle communication system, on-board unit, recording medium and communication method

MITSUBISHI HEAVY INDUSTRIES MECHATRONICS SYSTEMS, LTD.


A camera apparatus which can perform detail enhancement on a selected set of color signals. Fundamental color signals are respectively detected by a plurality of imaging devices and output in response to vertical transfer signals. For color signals on which detail enhancement is not to be performed, the vertical transfer pulse is sent to the corresponding imaging device at a reference timing. For the selected color signals on which detail enhancement is to be performed, the vertical transfer pulse is sent to the corresponding imaging device at a timing which is ahead of the reference timing. In one embodiment, vertical transfer pulses of the reference timing are generated, and additional pulses which are ahead of the reference timing are also generated. In another embodiment, vertical transfer pulses are continuously generated, but some pulses are selectively suppressed or subtracted to produce pulses of two different timings.

The present invention relates to a camera apparatus and, more particularly to a 3-chip color video camera having a vertical detail enhancement function, for example.
3-chip video cameras have hitherto been known as color video cameras. A 3-chip video camera includes a dichroic prism disposed behind a camera lens for analyzing incident light from an object to provide three primary colors R (red), G (green), B (blue). Three solid-state imaging devices of the same size are disposed at the positions in which light rays thus analyzed by the dichroic prism are focused. The R, G and B color signals are respectively obtained from outputs of the three solid-state imaging devices.
According to this system, since optical paths of three primary colors R, G and B are independent, it is possible to freely correct colors by using filters, called trimming filters, disposed on the optical paths. As a consequence, optimal imager characteristics can be obtained with ease and reproduced color images will have satisfactory tonal value.
Recently, in order to compensate for deterioration in responses of a solid-state imaging device or to enhance sharpness, horizontal and vertical detail enhancement (compensating) processing has become available.
In particular, vertical detail enhancement processing uses a method called the RGB pixel shift method or the RGB image shift method. By way of example, when a detail is enhanced by using the R signal and the G signal (referred to hereinafter simply as "RG detail") for example, according to the RGB image shift method, the positions of R-channel and G-channel solid-state imaging devices are shifted by one pixel pitch (i.e., one line amount) relative to the reference position of B-channel solid-state imaging device.
Specifically, when the solid-state imaging devices are bonded to the dichroic prism, the B-channel solid-state imaging device is bonded to the prism such that the center of its image region is aligned with an optical axis of the prism for the color blue. The R-channel and G-channel solid-state imaging devices are bonded to the dichroic prism such that centers thereof are respectively shifted in the amount of one line in the vertical direction from the corresponding red and green optical axes of the prism, thereby realizing the RGB image shift method corresponding to the RG detail.
A principle of RG detail processing will be described with reference to FIG. 1 which shows an imager model in a CCD (charge-coupled device) solid-state imaging device of a FIT (frame interline transfer) system.
As shown in FIG. 1 of the accompanying drawings, a mark is picked up by imager portions of the R-channel and the G-channel at their imager regions at a position ranging from the Nth line to the N+3th line. Meanwhile, because the B-channel solid-state imaging device is shifted downwards by one line in the vertical direction, relative to the R-channel and G-channel solid-state imaging devices, the B-channel imager portion will pick up the same mark on its imager region at a position ranging from the N+1th line to the N+4th line.
During the next vertical blanking period, the signal charge thus picked up is transferred from the imager portion to the storage portion. The storage portions of the R-channel and the G-channel store signal charges corresponding to the mark at a position from the Nth line to N+3th line. The storage portion of the B-channel stores signal charges corresponding to the mark at a position from the N+1th line to N+4th line.
As a consequence, during the next effective horizontal scanning period, a signal charge of every line is transferred to a horizontal register at every horizontal blanking period. Due to the position of the image data picked up by the R-channel solid-state imaging device and the G-channel solid-state imaging device, these image data are read out earlier than image data picked up by the B-channel solid-state imaging device by one horizontal scanning period (1H). The R-channel and G-channel solid-state imaging devices output signals of -1H relative to an output signal of the B-channel solid-state imaging device.
The RG detail signal processing will be described below. The RG detail signal processing is effected by a detail enhancement circuit shown in FIG. 2. As shown in FIG. 2, the detail enhancement circuit is composed of two 1H delay circuits {circuits-for delaying signals by one horizontal scanning period: first 1H delay circuits (101R, 101G) and second 1H delay circuits (102R, 102G)} connected in series to imager signal lines for carrying out a detail enhancement processing (detail processing). The detail enhancement circuit further includes 3-input adding circuits (103R, 103G) connected to the 1H delay circuits 102R, 102G and amplifiers 104R, 104G). The amplifiers 104R, 104G have a gain of 2, and are connected between junctions (aR, aG) of the first 1H delay circuits (101R, 101G) and the second 1H delay circuits (102R, 102G) and the 3-input adding circuits (103R, 103G).
An R signal Sr(-1) of -1H is supplied to the first 1H delay circuit 101R from the preceding stage R-channel solid-state imaging device 105R through a contact bR of the preceding stage. An R signal Sr(0) of 0H from the first 1H delay circuit 101R is supplied to the second 1H delay circuit 102R. The R signal Sr(-1) of -1H from the contact bR and an R signal 2Sr(0) of 0H whose signal level was amplified by a factor of two by the amplifier 104 are supplied to the 3-input adding circuit 103R. An R signal Sr(1) of 1H from the second delay circuit 102R also is supplied to the 3-input adding circuit 103R. The 3-input adding circuit 103R calculates 2Sr(0)-(Sr(-1)+Sr(1))! to output a detail enhanced R signal dSr. This detail enhanced R signal dSr is output at an output terminal 106Ra of the 3-input adding circuit 103R.
FIG. 3 shows changes in the waveforms of signals obtained when the detail enhancement processing is carried out. The normal R signal Sr(0) of 0H is delivered to an output terminal 106Rb through a main signal line 107R led out from the contact aR.
In the G-channel, similarly, a G signal Sg(-1) of -1H is supplied to the first 1H delay circuit 101G from the preceding stage G-channel solid-state imaging device 105G through a contact bG of the preceding stage. A G signal Sg(0) of 0H from the first 1H delay circuit 101G is supplied to the second 1H delay circuit 102G. The G signal Sg(-1) of -1H from the contact bG and a G signal 2Sg(0) of 0H whose signal level was amplified by a factor of two by an amplifier 104G are supplied to a 3-input adding circuit 103G. Further, a G signal Sg(1) of 1H from the second delay circuit 102G also is supplied to the 3-input adding circuit 103G.
The 3-input adding circuit 103G calculates 2Sr(0)-(Sr(-1)+Sr(1))! to output a detail enhanced G signal dSg. This G signal dSg is output at an output terminal 106Ga of the 3-input adding circuit 103G. The normal G signal Sg(0) of 0H is delivered to an output terminal 106Gb through a main signal line 107G led out from the contact aG.
In the B-channel, a B signal (B signal of 0H) Sb(0) from the B-channel solid-state imaging device 105B is delivered to an output terminal 106Bb through a main signal line 107B without detail enhancement processing.
As described above, in the detail enhancement circuit, the two 3-input adding circuits 103R and 103G output the detail enhanced R signal dSr and the detail enhanced G signal dSg. The normal R signal Sr(0) of 0H, the normal G signal Sg(0) and the normal B signal Sb(0) are output from the main signal lines 107R, 107G and 107B, respectively. Therefore, it becomes possible to compensate for deterioration of response in the high frequency band in the solid-state imaging device.
In the detail enhancement processing, however, the solid-state imaging device(s) (e.g. 105R, 105G or 105B) for outputting the color signals to be detail-enhanced are mechanically bonded to the dichroic prism at a physical position shifted by one pixel pitch relative to a corresponding position for a solid-state imaging device for outputting a color signal which is not detail-enhanced or in an opposite positional relationship. Because the position of mechanical bonding determines which color signals may be detail-enhanced, the set of color signals which can be detail-enhanced is limited to one form when the camera apparatus is designed or manufactured.
Specifically, when the form of the RG detail shown in FIGS. 1 and 2 is changed to RGB detail form or G detail form, for example, the solid-state imaging devices 105R, 105G and 105B that had been bonded to the dichroic prism would have to be detached and bonded again to the dichroic prism at positions conforming to the desired detail form. Therefore, to change the detail form is very difficult and the selection of the detail form is limited accordingly.
To solve the above-mentioned problem, it is proposed to exchange the entire CCD block to thereby change between various detail forms. Under this proposal, there would be a multiplicity of CCD blocks, prepared in advance, in which the solid-state imaging devices are bonded to the dichroic prism according to each kind of detail form.
There are however seven detail forms, i.e., R, G, B, RG, RB, GB and RGB. Therefore, seven CCD blocks would need to be kept in stock in order to cope with the change of detail form. This would take much time and labor and would make the camera apparatus very expensive. Moreover, even when the solid-state imaging devices are mechanically bonded to the dichroic prism by an automation system, in order to manufacture the seven CCD blocks, a very small positional displacements must be accommodated. For instance, small positional displacements, such as one line amount of the imager region, would have to be determined and the solid-state imaging devices would have to be bonded to the dichroic prism with great accuracy in order to properly account for these small positional displacements. As a result, the manufacturing process becomes complex, the number of processes is increased and the manufacturing cost is increased.

Camera apparatus with detail enhancement processing


A coupling wedge for use with a ultrasonic phased array inspection system has a body with a bottom side configured to face the object to be tested and a front side generally oriented at an angle to the bottom side and a top side to be coupled with a phased array probe. The probe includes a plurality of apertures. The front side of the wedge has grooves formed with a plurality of reflectors that are positioned on the front side of the wedge, leaving a distance from the bottom side. The change in TOF values from the reflector to a specific aperture enable the determination of the temperature change in the wedge. An alarm to an operator or alternation of focal laws in the system for temperature compensation can be applied.

It is an object of the present invention to provide a hot weld seam inspection system and method which detects, alerts and compensates for wedge temperature variations.
In many ultrasonic weld seam inspections with a contact mode, such as in girth weld inspections during pipeline construction, phased-array probes are used with wedges. The wedges are usually of a thermoplastic synthetic material, in particular, a cross-linked polystyrene copolymer, for example Rexolite. The wedge is placed on the part surface, e.g., pipe surface, in close proximity to the weld seam which may be still quite hot from the welding. The ultrasonic wave propagates between the wedge and the pipe surface through a liquid couplant, which in most cases is water supplied by a pump. To allow the water to flow evenly, the wedge bottom is spaced from the part surface at a small gap of about 0.1 mm. The small gap is maintained, for example, by using four anti-wearing pins screwed in the four corners of the wedge bottom to prevent it from contacting the surface. The pumped water flows through the small gap completely filling it, which enables the ultrasonic coupling.
For an inspection using a pulse-echo mode, which uses electrical pulses coming from an acquisition unit to produce excitations, ultrasonic beams of longitudinal waves (LW) generated by different apertures of the phased-array probe travel in the wedge, propagate through the small water-filled gap, penetrate into the part and then reach the weld zone. If there is a flaw in the weld zone, some ultrasonic beams may be reflected by the flaw and then return to the probe. The probe, operating as a receiver, senses the returned ultrasonic beams and outputs the flaw echo signals to the acquisition unit for signal display.
When the ultrasonic beams travel through the interface at the wedge bottom surface, some of them skip back to the wedge front, potentially causing unwanted wedge echoes. To reduce the problem, damping material is casted to the wedge front, to absorb those unwanted echoes. The solidified damping material has an acoustic impedance very similar to that of the wedge material. To efficiently absorb and scatter the wedge echoes, grooves with serrated sections are machined in the wedge front. The grooves extend approximately perpendicularly to the plane of the probe face and are machined through the wedge front height. The larger the size of the serrations, the better the efficiency of the wedge echo attenuation. However, big serrations increase the distance from the exit points to the weld. A typical sectional shape of the grooves is an isosceles triangle with, for example, 3 mm side lengths.
In practice, an inspection of a newly welded seam involves the operator making sure that the pipe surface temperature is well below the water boiling temperature, i.e., 100° C. The temperature is typically measured with a non-contact infrared temperature gauge. A pipe or part surface at a higher temperature will boil the coupling water and generate bubbles that can seriously attenuate or even cut the ultrasonic wave propagation in the coupling water layer. Preferably, the part surface temperature suitable to weld inspection should be lower than 80° C.
The pumped water flowing around and under the wedge in the small gap serves not only as an ultrasonic wave couplant but also as a coolant that keeps the wedge temperature at that of the pumped water. In other words, normally the pumped water is a perfect coolant for the wedge. On rare occasions however, when, for example, the running water is interrupted or the wedge bottom contacts directly the hot part, the wedge temperature can be affected. Unlike metal parts such as a steel part, the longitudinal wave velocity in plastic wedge is much more sensitive to temperature changes. According to Snell's Law, a LW velocity change in a wedge can induce a change of the refraction angle of the inspection beams in the part, wrongly directing the beams in the part and possibly causing a total miss of the weld zones being inspected. The requirements for temperature condition in girth weld inspections can be found in Section 9.4.3 Temperature Differentials and Control, in Standard Practice for Mechanized Ultrasonic Examination of Girth Welds Using Zonal Discrimination with Focused Search Units, Designation: E 1961-98 (Reapproved 2003)e1, ASTM International. What is even more complex is that, once the wedge is heated, the temperature field in it is normally a function of time, which makes compensation of the temperature change in the wedge by modifying the focal laws in real time very complex and difficult. Even if this method was feasible, it would be too expensive to provide it for the rare and accidental event of a wedge temperature change. Therefore the efficient way to counteract the temperature change in a wedge, is to monitor for temperature changes, and to record an alarm for the event. Then the operator can take measures to deal with the event and can continue the inspection after the temperature level in the wedge has been restored.
The following prior art addresses the subject of wedge temperature detection or wedge temperature real time compensation.
The General Electric pending patent publication US 2011/0247417 A1 discloses a method that uses wedge bottom as the reflector and use the variation of the time of flight (TOF) or the sound path from the PA probe to the wedge bottom as the indication of temperature change in wedge. The major drawback of the method is that the amplitude and TOF of the echoes from the wedge bottom can be affected by the part surface status (e.g.: when placing or lifting the search unit), possibly affecting the measurement accuracy of the TOF change.
Another inconvenience of this prior art is that the sound paths from the probe to the wedge bottom can change if the wedge bottom is worn, being potentially another factor of instability.
Yet another inconvenience of this prior art is that the zone for the detection of the temperature change is not near the weld. Because the zone of the wedge bottom with which the temperature change is monitored is below the PA probe, that zone is a little bit far from the hot weld. The separation is particularly obvious for a wedge of big angle that is often used to efficiently generate shear waves in the part.
The General Electric patent U.S. Pat. No. 8,192,075 B2 discloses another method for counterworking the temperature change in wedge. According to the method, the temperature change is sensed by two separate temperature sensors, the first one is placed on the part to measure the part surface temperature and the second one is placed on top of the wedge to measure the ambient temperature. According to the patent, the temperature field in the wedge as well as the LW velocity field in the wedge can be deduced from the temperatures measured at the two above locations, and then the focal laws are modified in real time by taking into account the LW velocity field in the wedge. This method is very expensive and very complex, and for the case of water coupling, is unable to take into account the thermal energy dissipation by the coupling water.
None of the above prior art allows directly detecting the gradient of the velocity changes in the wedge caused by the temperature changes.

Monitoring temperature variation in wedge of phased-array probe for weld inspection


The invention relates to a device for reducing the impact for a pedestrian relative to a vehicle, which vehicle is provided with windshield and a hood covering an engine compartment or a similar compartment in front of the windshield, which hood is provided with at least one hinge adjacent its rear section. The device may comprise at least one actuating mechanism for displacing the rear section of the hood from a rest position to a raised impact position, at least one airbag module being operative to inflate the airbag, causing the airbag to extend out from the rear section of the hood, and an airbag module associated with each actuating mechanism, whereby the reaction force of an operative airbag causes the actuating mechanism to assume the impact position. The invention further relates to a vehicle provided with such a device.

Present impact reducing devices may comprise arrangements such as impact reducing hoods for avoiding direct hood-to-engine contact or an inflatable external airbag system of a motor vehicle for protection of people outside of the motor vehicle in the event of a collision between the motor vehicle and a pedestrian, a bicycle, or a motorcycle. As a motor vehicle collides with a pedestrian, a bicycle, or a motorcycle, the pedestrian, a rider of the bicycle, or a rider of the motorcycle, may be hit at his or her lower body with a front body of the motor vehicle so as to land on a hood covering the top of the vehicle front body. Following this primary collision, the pedestrian may suffer a secondary collision with the windshield and/or the pillars on either side of the windshield of the motor vehicle.
U.S. Pat. No. 6,182,782 discloses an impact reducing device, which is mounted to a motor vehicle. The impact reducing device is intended for reducing impact to a pedestrian involved in a collision with a motor vehicle. According to one aspect of the patent, there is provided a device for reducing impact to a pedestrian struck by a motor vehicle having a hood extending in a generally horizontal plane and covering a compartment in front of a windshield of the vehicle. The patent describes a mechanism for the displacement of the hood from a rest position to a impact position raised relative to the rest position, combined with an air bag module including an air bag, said air bag module being operative in cooperation with said displacement mechanism to inflate the air bag, causing the air bag to have a first cushion portion extending beneath the rear of the hood across at most the entire width of the hood and a second cushion portion extending out from the rear of the hood.
A problem with this solution is that it requires separate actuators for each individual component, including two actuators for displacing the hood and one actuator for the airbag. Each such actuator adds to the complexity of the system and the assembly of the vehicle. Every extra component will also take up space in an already densely packed environment. In addition, both the weight and the cost of the vehicle will increase.
Hence there exists a need for a solution that requires fewer components and takes up less space, while performing the same number of functions.

Device for reducing the impact for pedestrians


An exemplary system includes a measuring device to acquire non-contact thickness measurements of a wafer and a laser beam to cut the wafer at a rate based at least in part on one or more thicknesses measurements. An exemplary method includes illuminating a substrate with radiation, measuring at least some radiation reflected from the substrate, determining one or more cutting parameters based at least in part on the measured radiation and cutting the substrate using the one or more cutting parameters. Various other exemplary methods, devices, systems, etc., are also disclosed.

Wafers find a variety of uses in the semiconductor, solar energy and other industries. Wafer quality often depends on variables such as thickness and surface characteristics. Depending on end use, poor quality wafers may have uneven thickness or uneven surface characteristics; whereas, higher quality wafers may have substantially uniform thickness and substantially uniform surface characteristics. In the semiconductor industry, where wafers are used as a substrate, wafer quality can crucially influence mechanical and/or electronic yield of wafer-based semiconductor circuits.
Wafer thickness can affect mechanical, electronic and optical behavior or performance. With respect to mechanical performance, increased thickness can minimize detrimental effects of fabrication or use associated stresses. With respect to electronic and optical performance, wafer thickness is often an important variable. Further, wafer thickness is often defined by distance between an upper wafer surface and a lower wafer surface. Characteristics of one or both of these surfaces generally affect electronic and optical performance.
Industries that rely on wafer-based technologies typically seek to control wafer thickness through any of a variety of conventional manufacturing and measurement techniques. In the semiconductor industry, wafer thickness may be controlled through various processing techniques that involve wafering (sawing), etching, and polishing, which typically produce flat wafers with substantially parallel surfaces. Thickness measurement of such wafers is fairly well defined and straightforward. For example, conventional measurement techniques include use of a dial gauge (e.g., a manual, mechanical measurement, generally used in the laboratory for a small number of wafers) and use of impedance (e.g., measurement of capacitance or eddy current loss in a radio frequency bridge configuration). Some conventional techniques, such as those that rely on impedance, can be implemented in a non-contact manner. For example, a coil may create an electromagnetic field proximate to a wafer, without actually contacting the wafer, and thereby generate one or more eddy currents in the wafer. Information related to the generated current or currents is then used to determine wafer thickness. Various impedance techniques can be quite rapid, on the order of a few seconds for each wafer, but they require knowledge of wafer properties such as resistivity. Further, impedance techniques are not well suited for determining or mapping variations in wafer thickness.
In general, the solar energy industry imposes certain demands on wafer quality. Such demands often need to be amenable to high throughput. For example, a typical manufacturing facility may process 50,000 wafers per day wherein a reasonable fraction of these wafers must be subject to measurement techniques to provide meaningful quality assurance. Concomitantly, such measurement techniques should be quite rapid. Other demands relate to wafer morphology, noting that wafers used in the solar energy industry are typically not flat. For example, silicon-based ribbons can exhibit surfaces that are substantially non-parallel with substantial variations in surface morphology. In such instances, an "average" thickness measurement and/or a thickness profile are useful. Yet other demands concerns crystallinity, i.e., the crystalline or multi- (or poly-) crystalline nature of wafers. Conventional impedance techniques can produce inaccuracies for multi- or poly-crystalline wafers because of extraneous impedance associated with grain boundaries and defects. Surface characteristics impose other demands because wafers used in the solar energy industry typically have some substantial degree of surface texture that acts to reduce surface reflectance and maximize optical absorption. Various aspects of surface texture can lead to inaccuracies in determination of thickness and/or surface characteristics. For example, surface roughness can be particularly detrimental for determinations based on optical measurement techniques.
Surface texture includes roughness and waviness, in addition, many surfaces have lay (e.g., directional striations across the surface). Roughness includes the finest (shortest spatial wavelength or spatial periodicity) irregularities of a surface. Roughness generally results from a particular production process or material condition. Waviness includes more widely spaced (longer spatial wavelength or spatial periodicity) deviations of a surface from its nominal shape. Waviness errors are intermediate in wavelength between roughness and form error. Note that the distinction between waviness and form error is not always made in practice, and it is not always clear how to make it. Lay refers to the predominant direction of the surface texture. Ordinarily lay is determined by the particular production process and geometry used. For example, turning, milling, drilling, grinding, and other cutting tool machining processes usually produce a surface that has lay: striations or peaks and valleys in the direction that the tool was drawn across the surface. Other processes produce surfaces with no characteristic direction: sand casting, peening, grit blasting, etc. Sometimes these surfaces are said to have a non-directional, particulate, or protuberant lay.
Clearly, the above demands are difficult to meet. The difficulties are further intensified by a need for minimizing the equipment and the measurement costs. The solar cell industry typically uses wafer weighing as a technique for monitoring wafer thickness while impedance-based techniques are often used to measure thickness of a very small number of total wafers in a single wafer production facility.
The solar energy industry has also identified a need to measure the spatial variations in wafer thickness. It has been observed that certain processes are affected by the local variations in the wafer thickness. For example, a process in solar cell fabrication involves firing a metal pattern to produce a low-resistivity contact. This process consists of screen printing a contact and spike-firing it at a temperature of about 800° C. in an infrared furnace. In this type of a furnace, the temperature acquired by a wafer depends on wafer thickness. Thus, a wafer that is thicker than the standard wafer (for which the process is optimized) will rise to a higher temperature. This can lead to the metal punching through a junction which will concomitantly degrade the open circuit photo-voltage (e.g., Voc) and fill factor of the solar cell. On the other hand, a thinner wafer may not be sintered properly, resulting (again) in a low fill factor. Of course, similar behavior may occur within different regions of a wafer if wafer thickness is not uniform.
Thus, within the solar energy industry and other industries, a need exists for methods, devices and/or systems for measurement of and determination of wafer variables (e.g., mechanical properties, mechanical behavior, electrical properties, electrical behavior, optical properties, optical behavior, etc.). In particular, a need exists for methods, devices and/or systems that can yield meaningful results for wafers that may have substantial texture (e.g., roughness, etc.) and/or substantially non-parallel surfaces. Further, a need exists for rapid, accurate, and/or low-cost methods, devices and/or systems. Various exemplary methods, devices and methods disclosed herein address aforementioned needs and/or other needs.

Wafer characteristics via reflectometry and wafer processing apparatus and method


A mechanism controls the motion of the weft insertion member in shuttleless looms. This mechanism comprises a double-threaded variable pitch cylindrical cam and a slider having two pairs of frustoconical rollers. Each pair of frustoconical rollers is mounted on a thread of the variable pitch cylindrical cam. In operation, the cylindrical cam is able to rotate in a reciprocating manner by moving the slider in a rectilinear reciprocating manner. The mechanism is characterized in that the semi-conical angle of each frustoconical roller is formed such that the profile of the two threads of the variable pitch cam screw is easy to design and manufacture. In particular, the plane formed by the axes of each pair of frustoconical rollers is inclined at a predetermined angle in relation to the plane perpendicular to the axis of the variable pitch cylindrical cam and the predetermined angle is such that the thickness of each thread of the variable pitch cam screw is near constant, and uniform strength of each thread is obtained.

Referring to FIG. 1, the conventional weaving loom primarily comprises a warp reel 1, a harness 2, a shuttle 3 a grill or reed 4 and a cloth roll 5. Ordinarily, woven fabric is produced by combining a plurality of warp yarns and a weft in a particular relation, such as in an interlacing relation. Normally, the plurality of warp yarns are divided into upper warp yarns 6a and lower warp yarns 6b. The upper warp yarn 6a and the lower warp yarns 6b are respectively held by an upper harness 2a and a lower harness 2b such that a shed is formed between the upper warp yarns 6a and the lower warp yarns 6b. In weaving operation, a weft-carrying insertion member, which is also known as a shuttle 3 (hereinafter "shuttle"), moves back and forth through the shed in a particular motion. Whenever the shuttle 3 completes a cycle, the grill (i.e., reed) 4, which acts as a comb, beats the weft to the right side to make the woven fabric dense and then returns to the left. A weaving loom of this kind is a so-called traditional weaving loom.
By contrast, a shuttleless weaving loom uses a weft-carrying gripper instead of a shuttle, for example, in the rapier weaving loom. Referring now to FIG. 2, a schematic diagram of a shuttleless weaving loom is shown. A weft-carrying gripper 30 and a weft-drawing gripper 31 are carried by a flexible strap 33 which is wrapped around a wheel 36. The wheel 36 ( for example, a belt wheel or gearwheel) is in turn driven by a driving mechanism 35. During weaving, the weft-carrying gripper 30 and weft-drawing gripper 31 move in a certain reciprocating motion, for example, in a more or less sinusoidal motion (also known as simple harmonic motion). To obtain such a motion, the driving mechanisms for the non-traditional weaving loom are mainly of three types: jet loom, gear and crank loom, and variable pitch cylindrical cam loom. Of the above three types of weaving machines, the variable pitch cylindrical cam loom is increasingly popular due to its high insertion rate of the weft end.
Genini U.S. Pat. No. 4,052,906, discloses a mechanism for controlling the motion of the weft-carrying grippers in looms. With reference to FIG. 3, the mechanism employs a cylindrical cam 29 with two pairs of cylindrical wheels 28 moving on each thread of the cam screw 29. In such a mechanism, the cylindrical cam 29 is hard to manufacture and machine. Furthermore, the cylindrical wheels 28 suffer serious wear at high insertion rates. See FIG. 4, wherein Ohmura, U.S. Pat. No. 4,535,642 is diagramatically shown. The traversing mechanism of Ohmura's patent is primarily composed of a cam shaft 41 and a cam shoe 40. The cam shoe 40 is mounted freely slidable on the helical cam groove of the cam shaft 41 for reciprocating a guide member 42. In such a traversing mechanism, the cam shoe 40 and the cam shaft 41 must be made of extremely hard material such as tungsten carbide. Pezzoli, U.S. Pat. No. 4,624,288, discloses a mechanism to control the movements of weft insertion members in shuttleless weaving looms as shown in FIG. 5. In such a mechanism, a rotary rectilinear motion of the gearwheel is achieved by a variable pitch cylindrical cam 44 with two pairs of sliding blocks 43 with an involute profile. The first drawback of such a mechanism is that the sliding blocks 43 are difficult to machine. The second drawback of such a mechanism is that the mating precision of the variable pitch cylindrical cam 44 and the sliding blocks 43 is relatively high. The third drawback of such a mechanism is the contact surface of the variable pitch cylindrical cam 44 and the sliding blocks 43 are worn out at high operation speeds. Eventually, the positioning accuracy of the weft-carrying gripper or the weft-drawing gripper deteriorates.

Variable pitch cylindrical cam mechanism for controlling the motion of weft insertion members in shuttleless weaving looms


A leakage preventing structure for water ball decorations includes an reinforcing ring fitting and rotated to fix in an anti-leak rubber plug combined in a lower portion of a glass dome filled with a liquid and a decorative figure placed in the glass dome of the water ball decoration. Then the reinforcing ring properly ring properly expands and forces the anti-leak rubber plug contact tightly the glass dome so as to strengthen preventing function of liquid leakage from the glass dome.

This invention relates to a leakage preventing structure for water ball decorations, particularly to one having excellent function of leakage prevention.
A conventional water ball decoration shown in FIG. 6 is very common, consisting of a base 1, a glass dome 2, and an anti-leak rubber plug 3. A rotating ing mechanism is contained in the base 1, not included in this application and not shown in Figures. The glass dome 2 is filled with a liquid, having an open lower side 21 for a anti-leak rubber plug 3 to fit and adhered closely therein to prevent the liquid in the dome 2 from leaking out. A decorative FIG. 31 is housed in the glass dome and fixed on the rubber plug 3. The rubber plug 3 has an annular curved projection 33 on an outer annular surface to engage an annular convex 22 formed in the open lower side of the glass dome 2, for increasing mutual contact tightness.
However, the conventional water ball decoration described above may still happen to have its leakage prevention not enough to hamper the liquid in the glass dome from leaking out. In addition, the rubber plug may wear off owing to a long period of use, causing a very small gap between the glass dome as to form air bubbles in the liquid contained in the glass dome.

Leakage preventing structure for water ball decoration


Very shallow electrical junctions may be formed in an oxide free surface of a semiconductor by introducing an inert or reducing gas into a vacuum processing chamber, heating the semiconductor to between 750.degree. C. and 1100.degree. C., introducing a dilute solution of a dopant gas into the chamber, and exposing the semiconductor to the gases for about 0.5 to about 100 minutes, preferably between 10 and 30 minutes. A relatively wide range of surface dopant concentrations may be achieved thereby with dopant concentration controlled independent of junction depth. Non-oxide free semiconductor surfaces may be made oxide free by first heating the semiconductor surface in the presence of the reducing gas. This technique provides uniform surface dopant concentrations and is suitable for the formation of junctions in deep trenches and other features having high aspect ratios.

1. Field of the Invention
This invention generally relates to the formation of electrical junctions in semi-conductors and more particularly to the formation of very shallow junctions with controlled dopant concentration and junction depth.
2. Description of the Prior Art
The formation of very shallow electrical junctions, e.g., less than about 0.2 .mu.m deep, is currently a limiting factor in the development of advanced silicon integrated circuits. Such very shallow junctions can be formed when a p-type or n-type dopant is introduced into the surface of a semiconductor of the opposite conductivity type. Such p-n or n-p junctions may be used, for example, in the formation of the source and drain of insulated-gate field-effect transistors or in the formation of the base and emitter of bipolar junction transistors.
In certain bipolar junction transistor processes, a shallow, lightly doped junction is often used to form a link between an active intrinsic base region and the extrinsic base contact region. Shallow junctions may also be used to control the conductivity of sidewalls in trenches and other features formed in silicon.
Junctions in silicon surfaces have conventionally been formed by many techniques including ion implantation, doped glass and vapor diffusion. One of the limitations of ion implantation is the difficulty of achieving sufficiently precise depth control to reliably form very shallow junctions. The doped glass technique achieves the desired shallow junction depth but may not provide the needed range of dopant concentrations. Moreover, neither the ion implant nor the doped glass technique is normally considered suitable for creating shallow junctions on a semiconductor feature having a narrow opening, such as a deep trench.
Conventional vapor diffusion techniques have been considered for use in forming electrical junctions, including the two zone furnace process and the closed box process. Both of these techniques, which are discussed in more detail below, are typically limited to forming junctions with high dopant concentrations.
In the ion implantation method, dopant atoms of the appropriate type are ionized and accelerated toward a semiconductor surface, typically silicon. The ions penetrate the lattice of the silicon atoms to a degree determined by the ion energy, the ion mass, the orientation of the lattice relative to the ion beam, and the degree of crystallinity of the silicon. This technique offers good dopant control and good uniformity across the semiconductor surface, but it is often very difficult to control the depth of shallow junctions formed by this technique.
As stated above, one factor determining the depth of penetration of the dopant ions is the mass of the ions used. Ions having a higher mass, such as arsenic, are more controllable than ions having a lower mass, such as boron. Boron ions are preferred, but they experience less energy loss when passing through crystalline silicon and tend to channel into the spaces between adjacent atoms in the lattice. This results in the boron ions forming a deeper and poorly controlled junction.
Several approaches have been proposed to avoid the channeling effect of boron ions: misorienting the semiconductor surface relative to the ion beam; randomizing the ion beam by covering the surface with an amorphous film such as silicon dioxide; and randomizing the lattice by the implantation of a heavy ion such as germanium, tin or antimony, to create an amorphous layer of silicon on the surface of the semiconductor. With the last described approach, the amorphous layer may be recrystallized during a subsequent heat treatment to restore the lattice and activate the dopant.
Although these approaches have achieved some success in the formation of very shallow junctions using boron, these conventional approaches suffer from drawbacks. The first approach of misorienting the semiconductor surface relative to the ion beam is not completely effective. A small percentage of the boron atoms still tend to channel even at large angles. The second approach of covering the surface with an amorphous film suffers from a similar limitation, unless a comparatively thick film layer is used, in which case depth control is poor.
The third approach of implanting heavy ions requires an extra implantation step, using ions not conveniently available in production implanters. Further, the use of germanium or tin ions can result in defect structures which do not anneal out completely during the subsequent heat treatment. The use of antimony ions minimizes this problem, but antimony acts as an n-type dopant which adversely affects the resistivity control of the final doped region. Further, the presence of antimony requires higher concentrations of boron ions to achieve a given carrier concentration, limiting the use of antimony to relatively heavily doped junctions.
The second technique currently used for forming shallow junctions in silicon, drives in the dopant from a doped glass. A doped glass, as will be described below in greater detail, is formed on the surface of the silicon. The glass formation is followed by a heat treatment which drives the dopant out of the glass into the silicon. This technique allows comparatively good control of dopant dose and uniformity, at high dopant concentrations, and is usable in forming reasonably shallow junctions.
However, it is difficult to control the dopant concentration at lower concentration levels because the concentration changes greatly with only a slight change in the heat treatment temperature. A further drawback of this technique is that it requires extra processing steps.
During this technique, doped glass is typically formed on the silicon surface by introducing a dopant-containing gas into a high-temperature reaction furnace. The gas is reacted with oxygen either by itself to form an oxide of the dopant, for example B.sub.2 O.sub.3, or with a silicon containing gas such as silane to form a doped silicate glass on the surface of the semiconductor. Subsequent heating of the coated semiconductor surface results in diffusion of the dopant from the glass into the semiconductor. Dopant control is achieved by controlling the concentration of the dopant in the ambient gas from which the doped glass is formed and by varying the temperature and pressure within the furnace. After the diffusion step, the doped glass may be removed from the semiconductor surface.
One disadvantage of this technique results from the difficulty in controlling dopant concentrations. At dopant concentrations below the solid solubility of the dopant in silicon at the diffusion temperature, relatively minute changes in temperature result in significant changes in the concentration of the dopant diffused into the semiconductor surface.
This typically limits the reproducibility of this method to concentrations at or near the solubility of the dopant in silicon, typically about 1.times.10.sup.20 cm.sup.-3. Such high concentrations inhibit reliable formation of very shallow junctions because of concentration dependent diffusivity and other effects.
Another disadvantage of this technique is that extra processing steps are required prior to the diffusion of the dopant into the semiconductor surface. Thin oxides such as the native oxide of silicon are commonly found on the surface of silicon semiconductors. Such thin oxides significantly reduce dopant diffusion from certain doped glasses, for example, borosilicate glass. The controlled precleaning required to remove such oxides is difficult to achieve in conjunction with the typical doped glass process.
A further disadvantage of both the ion implantation and the doped glass techniques is their limitations as to the type of surface features for which they are appropriate. For example, they are not readily suitable for doping the sidewalls of a deep trench, found in a semiconductor by, e.g., local etching of the semiconductor surface.
The ion implantation technique is essentially a line-of-sight method. If the area to be doped is "visible" to the ion source, it can be implanted. Trench sidewalls, however, present an extremely small surface area to incoming ions, creating great difficulty in controlling the ion dosage. Control of the ion dose per unit area of the sidewall is aggravated by variations in the angle of the sidewall to the ion beam.
Such variations may be caused by variation of the sidewall slope introduced during etching, shifts in orientation of the surface relative to the beam during placement in the implanter, and variation in the beam angle due to scanning of the beam across the surface. The typical results of ion implantation at slight angles onto a wafer with significant surface topography are non-uniform doped regions and regions without dopant.
Use of the doped glass technique to dope the sidewalls of a deep trench also often produces unsatisfactory results. As described above, doped glass may be formed by reacting a dopant containing gas with an oxidizer to form an oxide of the dopant. This oxide is then deposited on the surface of the semiconductor. However, depletion of reactants typically causes oxide deposition and dopant concentration to vary as a function of depth within a trench.
As noted above, various vapor diffusion techniques have also been used to form electrical junctions. One such technique is known as the two zone furnace process. This technique utilizes a furnace having two individually controllable heat zones. A dopant source is placed in the first zone, and a semiconductor surface is placed in the second zone. A slightly oxidizing gas is passed through the furnace and transports the vapor from the dopant source in the first zone to the semiconductor surface in the second zone. This process typically produces a doped oxide on the surface of the semiconductor. The first zone controls the vapor pressure of the dopant and can be eliminated if the dopant source used is sufficiently volatile at room temperature.
This technique has been used with reasonable success to produce junctions with dopant concentrations at or near the solid solubility of the dopant in silicon at the diffusion temperature. At lower concentrations, a relatively minute change in temperature results in significant changes in the concentration of the dopant diffused into the semiconductor surface. This limits the reproducibility of the two zone technique to high surface concentrations of dopant in the semiconductor.
Another vapor diffusion approach is known as the closed box technique. This technique utilizes a closed box containing a semiconductor surface and a dopant source. The dopant source is a solution of the oxide of the dopant in silicon dioxide. When the box is heated to diffusion temperature, it fills with the vapors of the dopant. The dopant then diffuses into the semiconductor surface.
This approach is limited because the system cannot approach a satisfactory near-equilibrium condition except when the box is saturated with the dopant. With such high concentrations of the dopant in the box, the dopant concentration in the semiconductor saturates at the maximum solid solubility of the dopant in silicon at the diffusion temperature. Thus, this method also is typically limited to high concentrations of dopant in the semiconductor.
What is needed therefore is a technique for forming very shallow electrical junctions which have a wider range of surface concentrations than are conveniently available with conventional methods. The technique should be adaptable for use with a wide range of semiconductor features having narrow openings, such as deep trenches. The needed technique should avoid the problems of conventional techniques, such as the channeling of the ion implantation method and the high concentration limitation of the doped glass and vapor diffusion techniques.

Method of forming doped shallow electrical junctions


A keypad is operated by the user to generate keypad data indicative of a destination telephone number. A storage area stores data related to the calling plan and containing data indicative of call restrictions that may apply to the destination telephone number. A call restriction storage area is used to store user-selectable call restriction data. A processor accepts and uses keypad data to access the data storage area. The processor compares data indicative of call restrictions that may apply to the destination telephone number with the user-selectable call restriction data to determine if any user-selectable call restrictions apply to the destination telephone number. The processor sets an enable signal to an enabled state if no call restrictions apply to the destination telephone number and sets the enable signal to a disabled state if call restrictions do apply to the destination telephone number.

I. Field of the Invention
The present invention is related generally to a wireless communication device and, more specifically, to a system and method for call restriction within a wireless communication device.
II. Description of the Related Art
Wireless communication devices, such as cellular telephones, are widely used as a replacement for conventional telephone systems. In countries such as the United States, an extensive infrastructure already exists for conventional telephone systems. In lesser developed countries where the conventional telephone infrastructure is minimal or non-existent, wireless communications technology offers the possibility of an extensive communication system without the need for an extensive corresponding infrastructure. Wireless communication devices offer the convenience of portable communication from almost any location in the world. With a wireless communication device, a party can place local, long distance, or international telephone calls without the need for physical connection between the wireless communication device and a central switching office, such as a public switched telephone network.
Each country has specific telephone number assignments and rules for dialing telephone numbers within that country. These pre-designated rules are referred to herein as dialing rules, or calling plans. For example, the United States uses seven digits to represent a local exchange and telephone number. To place a local call, a user must dial seven digits corresponding to the desired destination telephone number. To place a long distance call within the United States, the user must dial a 1, followed by the destination area code and telephone number. Thus, a long distance call in the United States is represented by eleven digits. To place an international long distance call, the user must dial 011 followed by a country code and telephone number. It can be seen that the telephone dialing rules for the United States require a predetermined sequence of digits for local calls, domestic long distance calls, and international long distance calls. It should be noted that other countries typically use a different set of dialing rules.
While a wireless communication device offers convenience in communication throughout the world, it is subject to misuse if the wireless communication device is lost, stolen, or is subjected to other forms of unauthorized use. Therefore, it can be appreciated that there is a significant need for a system and method for call restrictions that are implemented by the wireless communication device.

System and method for call restriction in a wireless communication device


Systems and methods are provided for location determination in wireless communication networks. A client device with a location provider installed is configured to provide location data to a data engine server and to obtain location service from a positioning engine server or the location provider itself. The location provider based on one or more components implements the reference data delivery function and the client location determination function. The data engine server is configured to process the location data received from one or more client devices and maintain a location database. The data engine server based on one or more components implements the reference data retrieval function, station position calculation function, reference data management function, and assistance data delivery function, as it interacts with the client device. The positioning engine server is configured to process the location request data received from one or more client devices and calculate the locations of the client devices. The positioning engine server based on one or more components implements the positioning data retrieval function and device position calculation function, as it interacts with the client device. The location database stores the previously obtained location data.

A wireless mobile device can include one or more location-aware applications that are configured to perform location based tasks such as store finding and transit routing. Location-aware applications depend on positioning method to determining a location of a wireless mobile device. A positioning method is configured to incorporate a satellite positioning system receiver in a wireless mobile device and to specify a real-time location of the wireless mobile device by use of only signals from satellites. Satellite based positioning can provide high accuracy, but require a positive line of sight between satellites and the wireless mobile device. In open sky areas where satellite positioning signals seldom are obstructed, the wireless mobile device can receive sufficient line of sight signals from satellites. However, satellite based positioning is largely ineffective while a wireless mobile device is within shadow areas. Further, receiving and processing satellite positioning signals may consume substantial energy and hence shorten battery duration.

Server-based positioning system architecture


Multiple non-blocking FIFO queues are concurrently maintained using atomic compare-and-swap (CAS) operations. In accordance with the invention, each queue provides direct access to the nodes stored therein to an application or thread, so that each thread may enqueue and dequeue nodes that it may choose. The prior art merely provided access to the values stored in the node. In order to avoid anomalies, the queue is never allowed to become empty by requiring the presence of at least a dummy node in the queue. The ABA problem is solved by requiring that the next pointer of the tail node in each queue point to a “magic number” unique to the particular queue, such as the pointer to the queue head or the address of the queue head, for example. This obviates any need to maintain a separate count for each node.

1. Technical Field
The invention is related to first-in-first-out (FIFO) queues employing non-blocking atomic compare-and-swap (CAS) instructions.
2. Background Art
A FIFO queue may be used by various application or process threads which may wish to enqueue or dequeue certain data on the queue. Typically, a queue is a list of different memory locations containing particular data, and each memory location is typically referred to as a "node" of the queue. The nodes are kept in order by providing in each node a "next" pointer that points to the memory location of the next node in the queue. The head of the queue is the first node ("head node") while the last node is the tail node. The tail node's next pointer points to a predetermined number, such as NULL. A node is enqueued by inserting it at the tail so that it becomes the new tail node of the queue. This requires the thread to first determine which node is the current tail node. Nodes are dequeued at the head, so that the head node is dequeued and the next node becomes the head node. This requires the thread to first determine which node is the current head node. The queue has a head pointer pointing to the head node and a tail pointer pointing to the tail node.
Maintaining the integrity of the queue while permitting its concurrent use by a number of different threads is a difficult problem. To solve this problem, the queue design must address all possible pathological conditions that the queue could experience. For example, after one thread has identified the tail node in preparation for an enqueue operation, another thread may interrupt and enqueue another node onto the queue (which obsoletes the one node's prior identification of the tail node). As another example: the head and tail nodes may be one and the same node because it is the only node on the queue; and one thread may identify the tail node in preparation for enqueueing a new node onto the queue; but, before it can, another thread may dequeue and move the tail node to another queue (for example) without changing its next pointer from NULL. In this case, the one thread may still succeed in attaching the new node to what it still believes is the tail node of the desired queue, but would actually be enqueueing the new node on the wrong queue. This latter case is typically referred to as the "ABA problem" and is described extensively in the literature. It is plausible that such an event could occur even if there were more than one node on the queue in the following example: after the one thread identifies the tail node, actions by other threads cause the tail node to be moved to the head and then dequeued and re-enqueued on another queue before the one thread completes its enqueueing operation. In any case, the ABA problem entails the risk of a thread unknowingly enqueueing a new node on the wrong queue or other location.
Initially, the ABA problem was solved by providing, whenever one thread was in the middle of an enqueue or dequeue operation, a lock which protected the queue from being changed by another contending thread. However, such blocking queues are susceptible to large unpredictable delays in process execution, since a single thread can monopolize the queue, particularly if it is a low priority thread that is interrupted by other higher priority threads.
As a result, the art has sought a non-blocking queue (i.e., a queue with no locks) permitting concurrent access to the queue by more than one thread without suffering failures due to the ABA problem. In such a concurrent non-blocking queue, the ABA problem has been solved in ways that burden the queue and impair performance. One such concurrent non-blocking queue is described by Michael et al., "Simple, Fast, and Practical Non-Blocking and Blocking Concurrent Queue Algorithms," PODC, 1996. This publication describes a concurrent non-blocking queue in which the ABA problem is addressed by assigning an extra "count" field to the queue pointers such as the next pointer of the tail node. Thus, for example, each time the tail node is modified by any thread, the count associated with the next pointer of the tail node would be incremented. In the ABA situation, if the tail node has been dequeued and re-enqueued on another node, a thread trying to enqueue a new node onto the first queue would recognize that the next pointer "count" field of the what it believes to be tail node has changed, even if the next pointer still has the same value as before. Therefore the thread would not complete its enqueue operation, thereby preventing an ABA problem.
Another difficulty in the implementation of a non-blocking queue is the method of handling the case where the queue is empty; in other words, when there are no nodes in the queue. Support for enqueueing a node on an empty queue, or dequeueing the last node on a queue (leaving it empty) can greatly complicate the implementation, as each enqueue and dequeue operation would then need to maintain both the head and tail pointers. To simplify this case, the queue in the Michael publication keeps at least one node in the queue at all times. To implement this, the queue in the Michael publication must control the nodes, rather than letting threads enqueue or dequeue their own nodes. In the Michael publication, each node is selected from a list maintained for the queue. The data of interest is then stored in the node. Such data is taken from a thread and copied into the node for an "enqueue" operation. It is later copied out of the node and returned to a thread for a "dequeue" operation while the node itself is not, the node always being preserved for use with the queue. If the dequeue operation determines that the node being dequeued is the last node in the queue, it is left there to ensure that there is always at least one node in the queue.
The requirement that the queue allocate and deallocate the individual nodes constricts queue performance and constricts the manner in which threads may use the queue. This is especially true with regard to situations where the enqueue or dequeue operations may take place in an execution context from which memory allocation operations cannot be invoked (such as within an interrupt handler).
It is therefore desired to provide a concurrent non-blocking queue in which it is not necessary to maintain extra count fields and in which the threads themselves enqueue and dequeue any nodes they wish on the queue without any risk of emptying the queue.

Non-blocking concurrent queues with direct node access by threads


Some examples relate to controlling network traffic pertaining to a domain name based on a Domain Name System-Internet Protocol address (DNS-IP) mapping, An example includes receiving, in a cloud computing system, a local DNS-IP mapping for a domain name from respective Access Points (APs) in a virtual local area network (VLAN) along with geographical information of respective APs; generating a global DNS-IP mapping database comprising the local DNS-IP mapping for the domain name received from respective APs in the VLAN along with geographical information of respective APs, in the cloud computing system; and determining appropriate APs to distribute the global DNS-IP mapping, based on location information of respective APs.

The Domain Name System (DNS) is a naming database in which internet domain names are translated into numerical Internet Protocol (IP) addresses. It is a hierarchical naming system for computers or other resources connected to the Internet. Its purpose is to provide a layer of abstraction between Internet services (e.g., email) and the numeric IP addresses used to uniquely identify any given resource on the Internet. Simply stated, the DNS converts a name typed in a Web browser's address bar into an IP address.

Controlling network traffic pertaining to a domain name based on a DNS-IP mapping

Hewlett Packard Enterprise Development LP


A tubing hanger assembly is provided which includes an annular tubing hanger body, a lockdown feature, an annular load member positioned on the body below the lockdown feature and rotatable relative to the body, and an annular load shoulder axially displaceable relative to the body. The load shoulder is associated with the load member such that in a first rotational position of the load member the load shoulder is spaced a first axial distance from the lockdown feature, and in a second rotational position of the load member the load shoulder is spaced a second axial distance from the lockdown feature, the second distance being greater than the first distance.

Subsea hydrocarbon production systems typically include a wellhead which is positioned at the upper end of a well bore. The wellhead comprises a central bore within which a number of casing hangers are landed. Each casing hanger is connected to the top of a corresponding one of a number of concentric, successively smaller casing strings which extend into the well bore, with the uppermost casing hanger being connected to the innermost casing string. After the innermost casing string is installed, a tubing string is run into the well bore. The top of the tubing string is connected to a tubing hanger having a downward facing circumferential load shoulder which lands on a seat formed at the top of the uppermost casing hanger. In certain tubing hangers, the load shoulder is formed on a load nut which is threadedly connected to the tubing hanger body.
The tubing hanger is usually secured to the wellhead using a lockdown mechanism, such as a lock ring or a number of locking dogs, both of which comprise a number of axially spaced, circumferential locking ridges. The locking dogs are supported on the tubing hanger body and are expandable radially outwardly into a locking profile formed in the bore of the wellhead, such as a number of axially spaced, circumferential locking grooves, each of which is configured to receive a corresponding locking ridge. In order to ensure that the tubing hanger is properly locked to the wellhead, the vertical distance between the load shoulder and the locking dogs must be the same as the vertical distance between the seat and the locking profile, which is commonly referred to as the wellhead space-out. In this regard, the term "the same as" should be interpreted to mean that the vertical distance between the seat and the locking profile is such that the locking ridges can fully engage their corresponding locking grooves.
In tubing hangers in which the load shoulder is formed on a load nut that is threadedly connected to the tubing hanger body, the vertical distance between the load shoulder and the locking dogs can be adjusted by rotating the load nut relative to the tubing hanger body. Thus, once the wellhead space-out is determined, the load nut can be rotated until the vertical distance between the load shoulder and the locking dogs is the same as the wellhead space-out.
In the prior art, a lead impression tool (LIT) is sometimes used to measure the wellhead space-out. In subsea wellheads, the LIT is lowered on a drill string and landed on the seat. The LIT is then hydraulically actuated to press typically three circumferentially spaced lead impression pads into the locking profile. After the impressions are taken, the LIT is retrieved to the surface and mounted on a storage/test stand, which is then manually adjusted to match the lead impression tool. The tubing hanger is then mounted on the storage/test stand and the load nut is adjusted until the vertical distance between the load shoulder and the locking dogs is the same as the wellhead space-out.
Although the LIT provides a useful means for determining the wellhead space-out, the time required to run and retrieve the LIT can be relatively long, especially in deep water. Also, setting the tubing hanger on the storage/test stand and adjusting the load nut can be a time consuming process and is dependent on human interpretation.

Tubing hanger assembly with adjustable load nut


The invention relates to a massage appliance comprising a generally bell-shaped hollow body having a bottom opening defined by a peripheral edge. The hollow body has an internal partition extending substantially to the level of a plane containing said peripheral edge so as to define two mutually isolated compartments both connected to a pump member which serves to generate different desired degrees of suction in each of the compartments. A wave effect is thus obtained by means of the two areas of suction, thus reproducing the palpating-and-rolling action that has hitherto been performed manually in kinesitherapy.

The effect of suction on blood circulation when the suction is exerted locally on the human body has been known for a long time, e.g. as applied with traditional suction cups placed at predetermined fixed locations.
Document GB-A-213 028 describes a suction massage appliance comprising a bell whose inside compartment is connected to a suction bulb. A diametrical roller is provided level with the thrust edge of the bell to produce a wave effect when the appliance is moved. Such a device exerts only a very limited massaging effect.
Document DE-A-668 052 describes a massage appliance based on a pressure-and-vacuum principle, with a two-compartment bell, one of which is subjected to positive pressure while the other is subjected to negative pressure. The effectiveness of such an appliance appears to be very doubtful insofar as positive pressure has very little effect on blood circulation in the zone concerned.
Subsequent attempts have been made to improve the massaging action to obtain a wave effect by relying on mechanical means in combination with suction.
Thus, document GB-A-1 077 143 describes a suction massage appliance implemented in the form of an applicator pad surrounded by a peripheral skirt defining a thrust rim, the inside face of the pad being shaped with undulations to generate a wave effect.
More recently, a massage appliance has been developed making use of motor-driven rollers combined with a suction system. In such an appliance, the skin of the zone concerned is pinched between two parallel-axis rollers so as to form a fold between the rollers, and the suction is applied to the top of the fold of skin formed in this way. The practitioner thus displaces the appliance over the zone concerned of the human body, the rollers being rotated by an electric motor, and suction is triggered together with movement of the appliance which moves under drive from the motor-driven rollers.
An appliance of that type suffers from a certain number of drawbacks, both for the practitioner and for the patient being subjected to the massaging operation. The practitioner finds it difficult to observe the single fold formed between the rollers pinching the skin, and the therapeutic action of suction is restricted to the top of the fold formed in the skin, such that said action is de facto limited. Also, for the patient, the massage operation is uncomfortable because of the sensation of pinching exerted by the rollers, thus requiring the practitioner to be highly skilled in handling the appliance. Also, that known appliance is difficult to adjust in order to adapt it to various types of skin problem to be treated. Finally, it should also be observed that the appliance is of relatively expensive design insofar as it is made up of a large number of component parts (more than two hundred).

Massage appliance for moving over a predetermined zone of the human body


A method and a central subscriber database are provided for performing a permission status check in a mobile network. A mobile station is identified using subscription related identification data and equipment based identification data. When a determination is made that current subscription related identification data and current equipment based identification data have not been previously correlated a validation procedure is performed.

With the advent of mobile stations and wireless communication systems, mobile subscribers are granted location independent mobility with a number of other features and applications. One such feature is a detachable subscriber identification module identifying a particular mobile subscriber or associated subscription account. With a mobile station having a detachable subscriber identification module, such as a Subscriber Identity Module (SIM) in a Global System for Mobile (GSM) communication system, a mobile subscriber conveniently exchanges or changes his mobile equipment by merely removing his SIM card from the old mobile equipment and re-inserting it into the new mobile equipment. As a result, the mobile user no longer has to rely on a customer support or technicians to switch his mobile equipment from the old equipment to the new equipment while still retaining the same telephone number along with his personal settings and user information. However, with the physical separation between a subscriber identity module (SIM) identifying a particular mobile subscriber and particular mobile equipment providing wireless communications, two different identification data are needed for properly validating the mobile subscriber (or subscription) as well as the associated mobile equipment within the wireless communications network. As an illustration, a mobile equipment within a GSM network for communicating voice and a General Packet Radio System (GPRS) network for communication data is identified using an International Mobile Equipment Identification (IMEI) as standardized by the 3rd Generation Partnership Project (3GPP) Standard. Separately, as discussed above, mobile subscriber identification data or subscription data are identified using an International Mobile Subscriber Identity (IMSI) as further standardized by the GSM Standard, or, alternatively, using an Universal Mobile Subscriber Telephony System (UMTS) SIM (USIM), as standardized by the 3GPP Standard.
To determine whether mobile equipment is permitted within a particular mobile communication network, a permission status check on the mobile equipment needs to be performed. A permission status check performed on an IMEI as identification data for particular mobile equipment may be referred to as IMEI check. Such a permission status check is performed for a various reasons. One such reason may be to detect stolen mobile equipment. It may also be to detect virus infected mobile equipment which should not be granted access to a mobile network. The permission status check could also be used for performing "type approval" in order to identify mobile equipment not approved for use within a particular mobile network for technical, regulatory or compatibility reasons. A regulatory reason may be to "type approve" a particular terminal type as to not disturb other technical installations. Another technical reason may be to approve a particular terminal as to properly cooperate with existing network equipment within a mobile network.
The IMEI check for conducting the above described permission status check may be performed using a mobility management component in a Visitor Location Register (VLR) within the GSM network architecture or in a Serving GPRS Support Node (SGSN) within the GPRS network architecture. More specifically, an IMEI check is performed during a call control procedure for a call setup in a VLR serving a particular mobile station within a GSM network or, during a session management procedure, for a location area update, or for an attach procedure in an SGSN serving that mobile station within a GPRS network. An IMEI check may be further performed according to one or more rules defined by a serving SGSN or VLR further specifying when or how often an IMEI check needs to be performed for a served mobile station.
Reference is now made to FIG. 1 which is a block diagram illustrating a network architecture for GSM/GPRS networks which may be used in accordance with the above described permission status check procedures. Such a mobile network (MN) 5 comprises a mobile station (MS) 1, which comprises mobile equipment (ME) 11 and subscriber identity module (SIM) or UMTS SIM (USIM) 12. The MS 1 is connectable to a serving core network (CN) 3 via a radio network (RN) 2. One skilled in the art would understand that such a radio network would include base station transceivers (BTSs, not shown in FIG. 1) and base station controllers (BSCs, not shown in FIG. 1) for providing wireless communication links to the MS 1. The core network (CN) 3 further includes a Mobile Services Switching Center & Visitor Location Register (MSC/VLR, collectively herein after also referred to as the MSC) for switching voice calls and Serving GPRS Support Node (SGSN) for switching packets or data for the serving MS 1. Even though an MSC provides voice connection for a GSM system and an SGSN provides packet or data connection within a GPRS system, the MSC and SGSN 31 are illustrated as being co-located and residing on a single platform in FIG. 1. However, one skilled in the art would understand that MSC (including VLR) and SGSN could easily be located as two separate network nodes and independently functioning and interacting with the RN 2. The CN 3 is, in turn, connected to other Public Land Mobile Network (PLMN) or other Public Switched Telephone Network (PSTN) 4 for communicating with other networks, terminals and destinations.
To provide permission status check and subscriber validation process, the core network 3 further includes two different databases—an Equipment Identity Register (EIR) 32 as an equipment related database and a Home Location Register or Home Subscriber Server (HLR/HSS) 33 as a subscriber related database. The EIR 32 stores the IMEI data along with the associated permission status for the ME 11. The permission status may be requested by the MSC/SGSN 31 as described above using permission status request signals sent via an interface between MSC/SGSN 31 and EIR 32. The interface between MSC and EIR in the GSM network architecture is refereed to as an F interface and the interface between SGSN and EIR in the GPRS network architecture is referred to as a Gf interface.
The HLR/HSS 33 on the other hand is a centralized subscriber database handling subscriber related data. Subscriber related data may be requested by the MSC/SGSN 31 via an interface towards HLR/HSS 33 using the associated IMSI data identifying a particular mobile subscriber or subscription. For example the HLR/HSS 33 stores the IMSI associated to SIM/USIM 12 as subscriber related identification data.
Reference is now made to FIG. 2 illustrating a signal sequence diagram for performing both the mobile equipment permission status check as well as the subscriber validity check as performed in the conventional GSM/GPRS system as depicted in FIG. 1. More specifically, FIG. 2 describes a permission status check performed during a "network attach" procedure "attaching" a mobile station 1 to a particular mobile network 5. To request a registration with an MSC/SGSN 31, the MS 1 sends an attach request signal 201 to the MSC/SGSN 31. The attach request 201 includes the International Mobile subscriber Identity (IMSI) number associated with the SIM/USIM 12 (shown in FIG. 1) of the MS 1. After receiving the attach request signal 201 from the MS 1, the serving MSC/SGSN 31 then determines whether there is a need to perform a permission status check on the requesting mobile equipment in a process IMSI step 231. Such a determination can be made by determining whether a permission status check on that particular mobile equipment associated with the identified IMSI number has been previously performed by the serving MSC/SGSN 31. Alternatively, the MSC/SGSN 31 may determine to perform a permission status check based on a statistical determination or, preferably, in the event the mobile equipment has not been checked for a long period of time or for a number of preceding attach procedures. In any event, in response to a determination that the mobile equipment needs to be checked, the serving MSC/SGSN 31 then requests the IMEI number associated with the mobile equipment (ME) 11 serving that particular mobile subscriber. The MSC/SGSN 31 therefore sends an identity request signal 202 to the MS 1 requesting the MS 1 to provide the network with its equipment identification number. In response, the MS 1, for example, provides the IMEI number in an identity response signal 203 back to the MSC/SGSN 31.
In response to receiving the IMEI associated with ME 11, the MSC/SGSN performs a permission status check on the IMEI associated with ME 11 by sending a check IMEI signal 211 towards the EIR 32. The EIR 32 then looks up the current permission status associated with ME 11 and responds with a check IMEI response signal 212 containing the permission status of the ME 11. Such permission status may indicate the identified ME as being "white listed" indicating that the respective mobile equipment is deemed to be permitted for use, as being "black listed" indicating that the respective mobile equipment is deemed not permitted for use and should be barred, or as being "gray listed" indicating that the respective equipment is deemed permitted for use but should be monitored. According to the permission status of ME 11 indicated in the check IMEI response signal 212, MSC/SGSN then determines whether to accept or reject the requested attach procedure 201.
In case of a positive determination that the attach request is to be approved for that particular MS1, the serving MSC/SGSN 31 then performs yet another validation process by sending a update location request signal 221 to a HLR/HSS 33 associated with the identified IMSI number. The serving HLR/HSS 33, in turn, performs subscriber validation process to determine whether this particular mobile subscriber should be granted access to that particular mobile network and provides a update location response signal 222 with the access status back to the requesting MSC/SGSN 31.
As illustrated, it is rather inefficient for the serving MSC/SGSN to perform two different status checks or validations with two multiple databases. Accordingly, there is a need for simplified network architecture and more efficient signaling procedures to perform status checks on the mobile equipment as well as the mobile subscriber.

Method and database for performing a permission status check on a mobile equipment


Methods and systems for user definable prioritization of market information are disclosed. An example method to prioritize market information displayed in a window within a trading interface includes updating the market information displayed in the window at a first frequency, wherein the first frequency is to correspond to a first window priority. The example method also includes, based on a trigger activation, assigning a second window priority to the window, wherein the second window priority is to cause the market information displayed in the window to update at a second frequency, the second frequency different from the first frequency.

An electronic trading system generally includes a trading device in communication with an electronic exchange. The electronic exchange sends information about a market, such as prices and quantities, to the trading device. The trading device sends messages, such as messages related to orders, to the electronic exchange. The electronic exchange attempts to match quantity of an order with quantity of one or more contra-side orders.
Advances in how a trading device communicates with the electronic exchange have resulted in an increased amount of market information generated by the electronic trading system. The frequency at which the market information is conveyed via the electronic trading system is also increasing. The amount of computing resources used by a trading device running a trading application to process the high-frequency market information updates and to display these updates upon a trading screen can be very high. In some instances, the cost of computing resources used to process and to display the market information can adversely impact all other processing on the trading device.
Certain embodiments will be better understood when read in conjunction with the provided figures, which illustrate examples. It should be understood, however, that the embodiments are not limited to the arrangements and instrumentality shown in the attached figures.

This patent is subject to a terminal disclaimer.

User definable prioritization of market information

Trading Technologies International, Inc.