An image printing apparatus is capable of printing an image at various resolutions, such as 300- and 360-dpi systems. To drive a printhead at a printing position corresponding to the resolution of printing data, information on whether to discharge ink separately in the forward and return passes of the printhead is stored in the storage area of a RAM in advance in correspondence with the main scanning position of the printhead. Data (0 or 1) stored in the RAM is read out by using, as a RAM address input, a count value output from a printhead position detection unit that represents the current position of the printhead. Only when the readout data is 1, a printing position pulse is generated to print an image at an arbitrary resolution. By setting ink discharge positions separately in the forward and return passes, an image can be printed at a high precision.

FIG. 9 is a schematic view showing a conventional image printing apparatus using a color inkjet printing method.
In the image printing apparatus of FIG. 9, a motor 103 is driven in printing (drawing) an image on a printing medium 140 on a platen 106. A carriage 102 having printheads 120 to 123 is moved by a driving belt 109 to the position of a home position sensor 108. While the carriage 102 is moved along a forward pass indicated by an arrow X1 in the scanning direction, inks in black K, cyan C, magenta M, and yellow Y are discharged at a predetermined position from the printheads 120, 121, 122, and 123 in accordance with input image data, printing a predetermined image 133.
After the image 133 is printed by a predetermined length represented by 134 in FIG. 9, movement of the carriage 102 along the forward pass X1 of the scanning direction stops. While the carriage 102 is moved along a return pass indicated by an arrow X2 opposite to the forward pass in the scanning direction, the carriage 102 is returned to the start position (position of the home position sensor 108) for printing/scanning of the next image. While the carriage 102 is moved along the return pass, a feed roller 110 is rotated by a feed motor 107 to convey the printing medium 140 in a subscanning direction (direction indicated by an arrow Y) perpendicular to the main scanning direction by a length corresponding to the width 134 by which the image is printed by the printheads 120 to 123.
As described above, an image is printed on a printing medium while moving the carriage 102 in the main scanning direction, and the printing medium is conveyed in the subscanning direction by the width 134 of one band. This operation is repeated to complete printing of a color image.
Image printing operation in only the forward pass in the main scanning direction has been exemplified. Bi-directional image printing operation in both the forward and return passes in the main scanning direction is also possible. In this case, an image is printed in the forward pass, and the printing medium 140 is conveyed in the subscanning direction by a length corresponding to the width 134 of one band by which the image is printed by the printheads 120 to 123. After that, image printing is executed in the return pass in the main scanning direction, printing an image in both the forward and return passes. In FIG. 9, reference numerals 100 and 101 denote second feed rollers; and 111, a medium detection sensor.
The discharge timings of ink from the nozzles of the printheads 120 to 123 are generated by using an output signal from a linear encoder to be described later as a reference. The position of each printhead is detected by the linear encoder, and the linear encoder can detect the position at a precision corresponding to a necessary resolution (e.g., 1,200 dpi). In an image printing apparatus having such linear encoder, the image printing resolution and the precision of the image printing position are determined by a position detection signal output from the linear encoder.
The image printing apparatus realizes multicolor image printing by superposing black (K), cyan (C), magenta (M), and yellow (Y) inks discharged from the printheads 120, 121, 122, and 123 for image data (printing data) corresponding to the same pixel on the basis of position information from the linear encoder and the relative positions of the printheads 120, 121, 122, and 123. Hence, position information from a linear encoder 130 greatly influences the image quality.
At present, linear encoders used in such image printing apparatuses are generally a magnetic linear encoder, and an optical linear encoder 130 shown in FIG. 9. For example, the magnetic linear encoder is comprised of a metal linear scale plate formed by many magnetization portions in the scale unit, and a magnetic sensor which is attached onto the carriage 102 and detects magnetism at the magnetization portions of the linear scale plate.
As shown in FIG. 9, the optical linear encoder 130 is comprised of a band-like scale 131 which has a graduated grid and is formed by alternately printing a light-reflecting portion and non-reflecting portion on low-expansion-coefficient glass in the scale unit, and a sensor 132 which irradiates the scale 131 with light and receives light reflected by the scale 131. The sensor 132 is generally a device (light-projecting/receiving device) constituted by a light-projecting portion formed from an LED or laser source attached onto the carriage 102, and a light-receiving portion which is formed from a photodiode or phototransistor.
Either magnetic or optical linear encoder uses a home position as a reference position. Read pulse signals which are output from the sensor in the linear scale unit in response to movement of the carriage 102 are counted up/down by an encoder counter. The count value is read to obtain position information of the carriage 102 (e.g., Japanese Patent Laid-Open No. 2000-168151).
The image printing apparatus can print an image by a 300-dpi system, i.e., at resolutions of 1,200 dpi, 600 dpi, and 300 dpi for a linear encoder resolving power of 1,200 dpi, but cannot print an image at resolutions of 1,440 dpi and 720 dpi.
In general, the resolution of the image printing apparatus belongs to two systems: a 300-dpi system having resolutions of 300 dpi, 600 dpi, 1,200 dpi, . . . and a 360-dpi system having resolutions of 360 dpi, 720 dpi, 1,440 dpi, . . . . Most of the nozzle intervals of printheads used for image printing are formed in accordance with either system.
However, some recent image printing apparatuses print an image at an arbitrary resolution other than the 300- and 360-dpi systems, like an image printing apparatus which forms a liquid crystal filter. In the image printing apparatus which forms a liquid crystal filter, the landing precision of an ink dot discharged onto a printing medium must be as high as about several μm, and the cost of the image printing apparatus becomes high. Demands have therefore arisen for an image printing apparatus which can print an image at various resolutions such as the 300- and 360-dpi systems.
On the other hand, either type of encoder described above suffers a read position error depending on the component/assembly precision and scale patterning precision in manufacturing an encoder, and further a read position error caused by thermal expansion of the scale itself. These position errors are negligible in a general inkjet printer. In the image printing (drawing) apparatus for manufacturing a liquid crystal filter, the liquid crystal filter pattern is dense, and ink must be landed on a target position at a high precision. To realize this, the read position error of the encoder depending on the component/assembly precision and scale patterning precision in manufacturing an encoder must fall within the allowable range. A feed error depending on the pitching, yawing, and straightness of the carriage and printing medium moving means must be corrected to make the ink landing position error fall within the allowable range.

Image printing apparatus and control method therefor


A method of purifying 4,4'-diaminodiphenylmethane comprising partially melting a crystal of crude 4,4'-diaminodiphenylmethane and removing a melt to obtain a high purity 4,4'-diaminodiphenylmethane. By utilizing the method, a high purity 4,4'-diaminodiphenylmethane is obtained efficiently with a low level of energy consumption.

1. Field of the Invention
The present invention relates to a method of purifying 4,4'-diaminodiphenylmethane, which is useful as an intermediate in the preparation of polyurethane or as an additive for rubbers.
2. Description of the Related Art
4,4'-Diaminodiphenylmethane can be prepared by reacting aniline and formaldehyde. But, in addition to the desired 4,4'-diaminodiphenylmethane, many by-products such as polymeric condensates (e.g. polymethylenepolyphenylamine) and diaminodiphenylmethane isomers (e.g. 4,2'-diaminodiphenylmethane and 2,2'-diaminodiphenylmethane) are produced. Therefore, further purification of 4,4'-diaminodiphenylmethane is necessary to improve its quality.
However, using conventional rectification, cause a part of the 4,4'-diaminodiphenylmethane to be lost because of thermal deterioration, or the separation of by-products having close boiling points to that of 4,4'-diaminodiphenylmethane (such as diaminodiphenylmethane isomers) is difficult. Moreover, in an industrial scale production, rectification is not advantageous in view of energy consumption, and facilities and equipment requirements.
It has been proposed to purify 4,4'-diaminodiphenylmethane by forming an adduct of 4,4'-diaminodiphenylmethane with an alkali metal halide or cyanide, separating the adduct and decomposing the adduct to recover 4,4'-diaminodiphenylmethane (GB Patent No. 1 169 127), or by condensation reacting aniline and formaldehyde, and diluting, partially neutralizing, crystallizing and neutralizing the product (Canadian Patent No. 745,173). However, these methods are troublesome or insufficient in purification effects, or provide low productivity for the desired product per unit volume. Therefore, these methods are unsatisfactory for the industrial production of 4,4'-diaminodiphenylmethane.

Method for the purification of 4,4'-diamino-diphenylmethane


In one embodiment, a data set is received at a network service element of a network service, a location record for that data set is generated, and the location record is sent to a location registry within the network service to monitored locations of that data set within a network service. The network service element is operatively coupled to a communications link. The location record is generated based on a portion of the data set and a cryptographic key associated with the network service element. The location record uniquely identifies the presence of the data set at the network service element.

On-demand, elastic, and/or dynamic network services can provide flexible data processing and/or data storage. Such services allow users to access computing and/or storage resources as needed and/or to pay only for the computing and/or storage resources accessed. Additionally, such services are often distributed and hosted at physical computing resources (e.g., computer servers) in multiple geographic locations. Furthermore, implementation details of such services are typically opaque to the user.
Typically, the user does not, therefore, know or control at which physical computing resources within the service the user's data is stored and/or processed. Rather, the service typically determines at which physical computing resources the data should be processed and/or stored based on, for example, a present load or usage of the system, scheduled maintenance of physical computing resources hosting the service, detected error or failure conditions within the service, and/or other factors. As a consequence, the user of such a system is typically unable to determine at which geographic location the user's data is stored or restrict the user's data to or from one or more geographic locations.

Methods, apparatus and systems for monitoring locations of data within a network service

Hewlett-Packard Development Company, L.P.


A method of sensing a component held by a nozzle of a pick and place machine is provided. The method includes engaging a source of illumination and recording a reference background image when no component is held by the nozzle. Then, a component is adhered to the nozzle. A shadow image of the component is detected while the component is held by the nozzle. The detected shadow image of the component is adjusted based upon the recorded reference background image. Positional information relative to the component held on the nozzle is computed using the adjusted shadow image. The component is then mounted upon a workpiece using the positional information.

Pick and place machines are generally used to manufacture electronic circuit boards. A blank printed circuit board is usually supplied to the pick and place machine, which then picks individual electronic components from component feeders, and places such components upon the board. The components are held upon the board temporarily by solder paste, or adhesive, until a subsequent step in which the solder paste is melted or the adhesive is fully cured. The individual electronic components must be placed precisely on the circuit board in order to ensure proper electrical contact, thus requiring correct angular orientation and lateral positioning of the component upon the board.
Pick and place machine operation is challenging. In order to drive the cost of the manufactured circuit board down, the machine must operate quickly to maximize the number of components placed per hour. However, as the state-of-the-art of the electronics industry has advanced, the sizes of the components have decreased and the density of interconnections has increased. Accordingly, the acceptable tolerance on component placement has decreased markedly. Actual pick and place machine operation often requires a compromise in speed to achieve an acceptable level of placement accuracy.
One way in which pick and place machine operation is efficiently sped up is in the utilization of a sensor that is able to accurately evaluate both the position and angular orientation of a picked component upon a vacuum nozzle or quill, while the component is in transit to the placement site. Such sensors essentially allow the task of determining the component position and orientation upon the vacuum quill to be performed without any impact on placement machine speed, unlike systems that require separate motion to a fixed alignment sensor. Such sensors are known, and are commercially available from CyberOptics Corporation, of Golden Valley, Minn., under the trade designation Model LNC-60. Several aspects of these sensors are described in U.S. Pat. Nos. 5,278,634; 6,490,048; and 6,583,884.
These laser-based alignment sensors are used in pick and place machines to measure the offset (x, y and θ) and size (Sx, Sy) of picked components. Laser-based alignment sensors generally transmit the measured offset values to the pick and place machine controller, so that the controller of the machine can correct for the offset and accurately place the component upon the circuit board at the placement site. Additionally, the part size (Sx, Sy) features are also measured and transmitted to the pick and place machine allowing the pick and place machine to detect incorrect part size, or other problems.
In a focused imaging system, the relatively large numerical apertures used to acquire images tend to cause dust on intervening surfaces to be appreciably out of focus, which in turn minimizes the effect of dust on the image. However, for reasons of compactness and low cost, it is often desirable to use shadow imaging. Shadow imaging is a technique where illumination is cast upon a component to be detected, and the detector is placed behind the component to detect the shadow cast by the component as the component block some of the illumination. Unfortunately, with shadow imaging, Fresnel diffraction can cause serious disturbances to the image even from a small dust mote.
Providing a shadow-image sensing component sensor for pick and place machines with an improved resistance to disturbances caused by Fresnel diffraction would benefit the art of automated electronics assembly.

Component sensor for pick and place machine using improved shadow imaging


Apparatus for feeding material, in the form of discrete sheets, seriatim from a stack of discrete sheets. The sheet feeding apparatus comprises a support for a stack of discrete sheets. A sheet in the supported stack of discrete sheets is engaged by a friction mechanism for selectively removing such sheet from the stack. Such sheet is attracted to the friction mechanism by vacuum directed adjacent to the friction mechanism. The vacuum attraction increases the force of engagement of such sheet with the friction mechanism to facilitate removal of such sheet from the stack of discrete sheets by the friction mechanism.

The present invention relates in general to sheet feeding apparatus, and more particularly, to a friction sheet feeding apparatus including a vacuum assist mechanism to improve the overall reliability of the sheet feeding apparatus.
Modern reproduction equipment, such as copiers or printers or the like, are capable of operating at very high speeds. In order to assure that the equipment functions in a manner to reliably produce desired copies of original information, such equipment must include sheet feeding apparatus for handling original information-containing document sheets and sheets of receiver material for rapid, reliable transport through the equipment. The sheet feeding apparatus must operate to feed sheets at the necessary high transport speeds without damage to the sheets, and with a maximum of stoppages due to misfeeds or multifeeds.
Sheet feeding apparatus for carrying out the desired high speed reliable transport typically employ either friction or vacuum feeding devices for separating individual sheets from a sheet stack for transport through the reproduction equipment. Friction sheet feeders utilize a friction member to scuff a sheet to remove such sheet from the top or bottom of a stack of sheets. On the other hand, vacuum feeding devices include a member which attracts the top or bottom sheet from a sheet stack by application of vacuum forces to the member. The member, and the attracted sheet, is then moved to remove the sheet from the stack.
While both friction and vacuum type feeding devices can be designed to be generally reliable, each have certain inherent inadequacies. Particularly, friction devices are highly dependent upon the frictional characteristics of the material being fed. It is therefore difficult to design a single friction feed device which can, without substantial adjustment, accommodate reliably all the different materials used as original sheets or receiver materials which the reproduction equipment may have to handle. On the other hand, vacuum devices are highly dependent on other characteristics of the material being fed, such as their weight or porosity for example. Such devices require significant control mechanisms to provide optimum vacuum to reliably feed single sheets without misfeeds or multifeeds.


A family of integrated filter forward converters includes a filter inductor is magnetically included in the transformer assembly. A basic circuit includes a DC voltage source, two cross-coupled capacitors, a clamp diode, a power switch, two identical transformers (or equivalent to a transformer and a filter inductor), two rectifying diodes, a filter capacitor and a load resistor. Several useful versions can be obtained by modifying the basic circuit for different applications. Both the input and output currents of the present invention can yield continuous current operation.

1. Field of the Invention
The present invention relates to a family of integrated filter forward converter having continuous input and output currents.
2. Description of the Prior Art
U.S. Pat. No. 5,523,936 issued to Leu et. al. discloses a built-in input filter forward converter for dc-dc applications and U.S. Pat. No. 5,640,318 issued to Leu discloses another forward converter for off-line applications. FIGS. 1A and 1B illustrate such two prior arts of forward converter each having input filter function being magnetically included in the transformer assembly. Wherein power switch, clamp diode and two cross-coupled capacitors are respectively connected to a split-winding transformer. When the power switch is turned off, the transformer leakage inductance and cross-coupled capacitors form an effective input filter without interrupting the input current of the converter. Hence, continuous input current is maintained with no external input inductor required. However, both patented forward converters are single-ended, that is, both only operate as half-wave mode and still require an output filter inductor for smoothing the output current. A full-bridge topology that integrates transformer and output inductor magnetic functions into common magnetic assembly in U.S. Pat. No. 5,555,494 to George Q. Morris. FIG. 1C illustrates such a prior art of forward converter. However, Morris converter requires a large input filter to reduce the noises caused by a pulsating input current of a full-bridge converter.


An apparatus for monitoring a reference clock signal having a clock pulse train comprises a detecting block for counting pluses of a count clock signal to produce a count value and generate a count failure signal when the count value reaches a predetermined value, wherein the frequency of the count clock signal is larger than that of the reference clock signal; and a controlling block for generating a clear signal at every clock pulse of the reference clock signal to cleat the detecting block when the clear signal is inputted thereto.

The use of an assembly of electrical conductors known as "bus" is common in electrical circuit designs. The bus transfers data and a bus clock signal synchronously; that is, the data transferred on the bus should be synchronized with the bus clock signal.
For highly reliable data transmission, a duplex bus system having two buses (one active bus through which data is currently being transferred and one stand-by bus for use when the active bus is in failure) is employed.
The bus clock signal of each bus of the duplex bus system is constantly monitored by a clock signal monitor and the data transfer will be switched to the stand-by bus when the active bus fails to transfer the bus clock signal properly. In other words, if the clock signal of the active bus does not supply pulses of a predetermined frequency, the data transfer will be made through the stand-by bus.
In a conventional clock failure detection scheme for a duplex bus, the failure of one clock signal is detected by using the other bus clock signal as a reference signal.
However, the conventional bus clock monitor cannot detect the failure of both bus clock signals occurring at the same time since there will be no reference signal working properly.


The friction drag decreases and the friction resistance decrease ship that improves fuel cost is offered.

It is known that the hull friction resistances in water will become smaller by supplying air bubbles to the surface of a moving hull.
A pipe is attached along lateral aspects of the hull as a means to send air to the bubble generator prepared in the ship's bottom (lateral surface), and a means to supply air with this pipe is described in JP 11-180380 A (Prior art 1) and JP 2000-296796 A (Prior art 2).
In order to reduce frictional resistances effectively, it is desirable that bubbles stop at the hulls surfaces for a long time, and, for that purpose, it is required that bubble diameter should be small as possible. Such microbubbles are generated according to the Kelvin-Helmholtz Instability Phenomenon as described in JP 2002-2582 A (Prior art 3).
Prior art 3 describes that, preparing a recess in the shell (immersion surface) of a ship's bottom, and connecting a gas tube which supplies air to this recess, negative pressure portion having a wedge shape is attached to the upper stream side of a recess, and generates the Kelvin-Helmholtz-instability phenomenon to make microbubbles in a recess.
Moreover, in JP 4070385 A (Prior art 4), the technology of employing a wing is disclosed as a means which make microbubbles instead of the wedge-shaped negative pressure formation part disclosed to the patented documents 3.
[Prior Art 1] JP11-180380 A
[Prior Art 2] JP2000-296796 A
[Prior Art 3] JP2002-2582 A
[Prior Art 4] JP4070385

Abstract: Duct 3 is divided into two or more independent chambers 5, with partition 4 according to the longitudinal direction; piping 6 is introduced in each chamber 5 and penetrates through partition 4 to supply air to each chamber 5. Air is supplied by assistance compressor 7 through piping 6. Opening 8 is formed in the lateral aspect of each chamber 5, and microbubble generator 10 is installed in this opening 8.


A zoom lens system includes a first lens group which has a negative refractive power, a second lens group which has a positive refractive power, and a third lens group which has a positive refractive power in this order from the object side and changes the distances among these lens groups to vary the power from the wide-angle end to the telephoto end. The second lens group has a three-element cemented lens including a positive lens c1, a negative lens c2, and a positive lens c3.

This invention relates to a zoom lens system for a digital camera, video camera or the like, particularly to a compact and axially-thin zoom lens system of, for example, a power variation ratio of 3 and a field angle of 60° or more at a wide-angle end which is fit for CCD (charge coupled device) and CMOS (complementary metal-oxide semiconductor).
Recently, there have been lots of digital still cameras and video camera which use CCDs or CMOSs. Particularly, only thin cameras have enjoyed an increasing demand. A three-element cemented lens system whose axial length is suppressed has been disclosed for such thin cameras. (See Patent Document 1.)
[Patent Document 1] Japanese Non-Examined Patent Publication 2004-325975
The second lens group of the zoom lens system of Patent Document 1 is composed of a positive single lens and a three-element cemented lens system which contains a negative lens, a positive lens, and a negative lens in this order when viewed from the object side. When the second lens group is configured in this manner, the lateral magnification of the three-element cemented lens system cannot avoid from becoming bigger. Therefore, as the lens errors of the lens thickness occur, the paraxial values such as focal lengths and back-focus and aberration changes will be greater. This is a problem.


Lawn and garden edging segments for end-to-end adjacent installation on an outdoor ground surface, with each edging segment comprising an elongate member having a pair of laterally extending arms defining separate sides of the edging segments and extending along the elongate length of the edging segments. The arms each include a lower wall, an upper wall on a top side of the edging segment and an edge wall. A lower projecting member extends outwardly from a bottom side of the edging segment between the lower walls of the arms the projecting member extending beyond planes defined by the lower walls. The edging segments are configured for installation such that the projecting members are positioned within a groove formed in the ground with the lower walls of the arms extending outwardly adjacent the groove.

The present invention is directed to an edging member or assembly for lawns and gardens, with the edging being used as a divider such as for lawns and gardens.
Edging is used as a divider between areas, such as between lawn or garden areas and landscaped areas in which mulch, rocks or other materials are placed for landscape design purposes. Conventional edging is constructed of metal or plastic material that forms a vertical wall and is positioned and retained by stakes and/or by the edging itself being driven into the ground. Such edging is often dislocated due to shifting in the ground, such as from freeze-thaw cycles, and/or must be readjusted. Conventional edging and the associated stakes may present a trip or other type of hazard as they project from the ground and include sharp edges or corners. In addition, due to the generally upright manner in which the edging is installed lawn mowers are not able to cut grass that is immediately adjacent the vertical wall defined by the edging such that additional lawn maintenance steps must be performed, such as trimming of the grass.


A personal watercraft having improved bottom hull shapes in general, and improved center keel shapes in particular. The center keel can have a substantial section over which the keel angle becomes sharper progressing from front to rear, and the concavities on either side of the center keel become deeper progressing from front to rear. The center keel can have a point of maximum downward slope on either side of the keel centerline, with the maximum vertically downward slope becoming greater with greater rearward distance over a section of the personal water craft bottom hull. The bottom hull can have keel troughs on either side of the keel centerline that become deeper over a section of the personal watercraft bottom hull, traveling from front to rear over that selected section of personal watercraft bottom hull. The center keel shape can provide a smoother ride and improved handling in rough water. When the bottom hull is in the water, the sharper keel angle and deeper troughs leading to the transition region and the tunnel of the watercraft can more effectively channel water to the tunnel and to the jet pump.

Personal watercraft hull designs typically have a center keel shape that remains essentially constant over the length of the watercraft, or transitions to a flatter, shallower keel shape as the tunnel to the rear of the watercraft is approached. Some personal watercraft have substantially rounded, shallow-angled, or even flat center regions, disposed between longitudinal chines running along the underside of the personal watercraft. The conventional design has proved adequate in the past in general, but applicants suspected that the conventional hull design could be changed to improve personal watercraft handling in rough water.


A method is described for making low-stress single crystals with a hexagonal crystal structure, which has a crystallographic c-axis perpendicular to a [0001] surface. A single crystal maintained at a temperature under the melting point of the crystal raw material is dipped in a melt of the crystal raw material, whereby a solid-liquid phase boundary is formed. The crystal is subsequently drawn with an upwardly directed drawing motion e.g. by the Czochralski method. The method is characterized by drawing the crystal along the c-axis so that a temperature gradient of at least 30 K/cm is present in the crystal within a centimeter of the solid-liquid phase boundary and by subsequently performing a tempering treatment on the resulting single crystal. The method is especially suitable for corundum crystals, such as sapphire, which are used as substrates for semiconductor components, such as LEDs.

1. The Field of the Invention
The present invention relates to a method of making low-strain or strain-poor single crystals with a hexagonal structure, especially corundum single crystals, by the Czochralski method and a subsequent tempering process, to the low-stress single crystals themselves obtained by the method, and to their use for making electronic and electrical components.
2. Description of the Related Art
The manufacture of III-nitride semiconductor elements has made the development of many electronic components for high temperature engineering and high-energy engineering, such as laser applications, possible. Above all blue and white light emitting diodes (LED) that produce high light intensity were made possible by these elements, also their mass production. The principal problem with this is sufficient availability of suitable substrate material. A suitable substrate must, above all, have a high transparency and a sufficient resistance to corrosive action during manufacture of semiconductor structural elements. It must have sufficient form-stability at temperatures above 1300 K, in order to permit a uniform semiconductor layer growth.
Thermal properties, such as thermal expansion and heat conduction, must similarly have suitable values. Moreover a so-called mismatch between the crystal lattice of the substrate and the crystal lattice of the crystalline gallium nitride layer must be as small as possible, so that the gallium nitride layer can be epitaxially applied to the substrate. Currently sapphire is used as the substrate. The physical properties of sapphire are close to those of GaN and other semi-conductor variants used with it, such as AIN, GaN, InGaN or InGaAl. So-called wafers are used as substrates. They are thin substrate disks with diameters of a few inches (2 to 4″). The smallest mismatch between sapphire and GaN results, when wafers with a <0001> orientation are used as substrates. The mismatch of the lattice constants of the sapphire in relation to the GaN is minimal with this <0001> orientation. In this <0001> orientation the [0001] surface is the wafer surface and the crystallographic c-axis is perpendicular to the wafer surface.
The so-called Czochralski method, in which a seed crystal is immersed in melted raw material and slowly drawn from this melted raw material, is a suitable method in wide spread use for sapphire growth. This Czochralski method has the advantage that a true crystal growth and thus an ordered structure is possible in contrast to other known crystal growth methods. It is generally problematical that a single crystal of high quality can only be made by the Czochralski method when the seed crystal is withdrawn from the melted raw material parallel to the crystallographic m-direction of the sapphire. This m-direction is oriented at an angle of 90 degrees with respect to the c-axis. A crystal growth also partially occurs according to the Czochralski method, when the drawing direction is oriented at an angle of 60° to the c-axis (r-direction). In this case it is disadvantageous that the desired wafer in the <0001> orientation must be costly obliquely cut out from the thus grown single crystal. This reduces the yield and requires great processing effort in sapphire because of its great hardness. Moreover the wafer so obtained has unsymmetrical relaxation behavior of the intrinsic stress and thus an unsymmetrical deformation of the wafer during subsequent temperature treatment. This behavior reveals itself as interference with later epitaxial growth process, for example growth of GaN on the wafer. It is due to the high temperatures occurring during epitaxial growth processes and thus causes the wafer to deviate from its required planarity. In the Czochralski method in which the crystal is drawn in the m-direction a comparatively great material waste measured in broken crystal volume in comparison to the obtained wafer surface area results. Also the wafer quality is disadvantageously influenced by deformation as a result of stress relaxation at temperatures above 1270 K. The deformation by stress relaxation reveals itself already during the grinding and polishing processes during manufacture of the wafer.
Up to now good results regarding crystal quality could not be obtained with the Czochralski method in the c-axis direction because the growing speed must be minimized according to the axial temperature gradient at the phase boundary. Also no economical manufacture of sapphire crystals was possible according to this process generally on account of the limited growing speed. The poor material quality was largely due to the fact that the growth occurred at the atomic smooth [0001] surface. However flaws arise already on this surface with only very little surface energy in this crystal system. Small angle grain boundaries also arise making the substrate material unusable for high quality electronic components.
The manufacture of as-uniform-as-possible stress-free oxidic single crystals is described in DD-A 202 901. A very flat temperature gradient is set in the entire growth chamber in a high frequency heating system. However it has been shown that this method is not suitable for mass produced products, such as substrates for semiconductor elements.

Method of growing hexagonal single crystals and use of same as substrates for semiconductor elements


A method corrects channel change errors in a media center personal computer system. The media center personal computer system has a personal computer coupled to an infrared (IR) remote control device and a tuner card coupled to an output of an external tuner. The method determines when channel change instructions have been sent from the IR remote control device to the external tuner. It then determines whether an output from the external tuner is changing and if not, resends the channel change instructions from the IR remote control device to the external tuner upon determining that the output from the external tuner is not changing.

Personal computers are increasingly being used to control external tuners, such as a satellite tuner, a cable set-top box, a television tuner, or the like, and record the output of these tuners. These personal computers are often known as media center personal computers (PCs) and the applications that run on them to control the external tuners and record their output are often known as media center PC applications. The PC can be programmed to tune the external tuner to a desired channel station and at a desired time. Typically, the external tuners are configured to responds to IR signals and the media center PC has one or more IR remote control device devices that transmits IR signals to one or more external tuners and one or more tuner cards to which the output(s) of the external tuner(s) is connected. In one typical media center PC configuration, the PC has an IR remote control device and tuner card for each external tuner. The IR signals transmitted by the IR remote control device include the appropriate command(s) to control the tuner, such as to change to a desired channel. For example, the IR signals include the digits of the channel to which the tuner is to change. Such personal computers often use the Windows Media Center software to run the media center application.
One problem that personal computers running media center applications using the Windows Media Center software have had is that in some cases, the tuner doesn't properly change channels when commanded to do so by the PC. For example, system delays during channel changing sometimes cause the external tuner not to receive proper channel information from the PC. For example, one or more digits of the channel may be dropped either due to the IR remote control device not properly transmitting the digits or the external tuner not properly receiving the digits. If this error causes the external tuner to tune to a channel that does not contain any video information, the media center PC will record a blank screen.
Heretofore, the solution to has been to slow down the transmission rate of the IR remote device. While this has proven effective for subsequent digits of the channel, it does not solve the problem when it is the first digit of the channel that is not properly sent by the PC or received by the external tuner.

Method of correcting channel change errors in a media center personal computer system


A water jacket is attached to an exhaust manifold connected to an exhaust port to annularly cover an outer side of an exhaust channel in the exhaust manifold. An engine cooling coolant is made to flow as a cooling medium of the water jacket of the exhaust manifold. An exhaust pipe in a siphon shape is connected to the exhaust manifold, a water jacket is attached so as to annularly cover an outer side of a front half portion of the siphon shape, and seawater is directly supplied into the water jacket to flow therein. Consequently, an exhaust device of an outboard motor practically having a compact structure and excellent exhaust performance and accordingly realizing excellent engine performance is provided.

1. Field of the Invention
The present invention relates to an exhaust device for discharging combustion gas from an engine mounted on an outboard motor.
2. Description of the Related Art
Main types of propulsion engines and propulsion systems of ships or boats include outboard motors, inboard-outdrive motors, inboard motors, and the like. Among them, in the outboard motor, which is called an outboard drive or the like, an engine, its auxiliary machines, gears and shafts of a driving system, a screw, and so on are integrally structured. Generally, the outboard motor is mounted on a transom board of a stern of a hull. Typically, it is mounted on a small boat or the like and has a steering function and a tilting function.
In the inboard-outdrive motor, which is called an inboard engine-outboard drive or the like as an installation method of a propulsion engine of a small boat or the like, an engine is mounted on an inboard stern portion, and a drive unit integrally made up of reduction gears, a forward and reverse clutch, a Propeller, and so on is disposed on an outer portion of the transom board.
In any of these outboard motors, inboard-outdrive motors, and inboard motors, when an engine being an internal combustion engine is mounted as a power source, an intake device supplying air for combustion to the engine and an exhaust device discharging exhaust gas after the combustion are very important devices because they have a great influence on engine performance. A stricter restriction is imposed on these devices when they are used in the outboard motor or the like than when they are used on land, because of their usage environment and the like. In particular, as for the exhaust device, it is very important whether this device is effectively adaptable to the use under such a condition, and various contrivances have been conventionally made.
Concretely, there have been conventionally known exhaust devices and the like in outboard motors and the like of this type, such as those described in the undermentioned patent documents. As disclosed in these patent documents, these exhaust devices have merits and problems of their own.
Further, especially regarding a muffler of an exhaust device, Patent Document 4, for instance, describes an example of dry in-air exhaust of an inboard motor (inboard-out drive motor). The structure in this example is the same as that in an automobile engine, but a portion from a catalyst to the muffler is disposed inboard.
Further, Patent Document 5 describes an example of dry in-air exhaust in PWC (Personal. Water Craft). In this example, a muffler portion has a dual structure and is water-cooled.
Further, Patent Document 6 describes an example of dry underwater exhaust of an outboard motor. In this example, it is possible to realize a compact size and enhance silencing performance, but exhaust pressure becomes high. As a solution, exhaust gas is discharged into the air by a separate system during an idling operation.
Further, Patent Document 7 describes an example of dry underwater exhaust of a POD-type inboard motor. In this example, exhaust gas is not discharged during an idling operation.    [Patent Document 1] Japanese Laid-open Patent Publication No. 2008-169707    [Patent Document 2] Japanese Patent No. 2984027    [Patent Document 3] Specification of U.S. Pat. No. 7,390,232    [Patent Document 4] Japanese Laid-open Patent Publication No. 2001-173443    [Patent Document 5] Japanese Laid-open Patent Publication No, 07-144697    [Patent Document 6] Japanese Laid-open Patent Publication No. 2003-003840    [Patent Document 7] Specification of U.S. Pat. No. 7,387,556
An outboard motor with catalyst described in Patent Document 1 has a problem that a catalyst is likely to be splashed with surrounding seawater flowing back in an exhaust channel during reverse drive because the catalyst is located near an exhaust exit end (propeller). Another problem is a need to sharply bend the exhaust channel in order to stow the catalyst in a cover, which increases a loss of exhaust pressure and does not allow an increase in engine output performance.
Further, in the device described in Patent Document 2, since a catalyst is located more downstream than a top of an exhaust pipe (riser), exhaust temperature at the position of the catalyst lowers and purification efficiency worsens. In addition, there are problems that it is difficult to discharge water resulting from the condensation (liquefaction) of vapor in the exhaust gas since the catalyst is located at a substantially horizontal position, and moreover, the catalyst is likely to be splashed with surrounding seawater flowing back from an exhaust exit end during reverse drive or the like because the catalyst is near the exhaust exit end.
The structure described in Patent Document 3 does not have the problems of the backflow water/condensed water since a catalyst is far from an exhaust open end and is located in an exhaust gas upflow region or rising section. However, it has a problem that the temperature of the catalyst cannot be increased and accordingly purification efficiency cannot be enhanced because exhaust gas is assembled in an exhaust pipe at a position far from an engine exhaust port (outside the whole length of the engine) and thereafter is connected to a pipe in which the catalyst is provided.
Further, in the inboard-outdrive motor having a dry exhaust device described in Patent Document 4, it is necessary to provide a pipe around exhaust system components and cool them by air so that surface temperature of the exhaust system components is sufficiently lowered in order to prevent thermal damage to a hull and other components. This has a problem that the hull (engine room) requires a large space and an effective use volume of the hull reduces.
Further, in the example of the dry exhaust in the PWC of Patent Document 5, since the muffler has the dual-pipe structure and seawater is supplied between the pipes for the purpose of cooling, a space around the muffler is smaller than that in an air-cooling dry exhaust method, but there is a problem of an increase in weight.
Further, in some of the other examples, indirect (circulation) cooling is adopted for cooling an engine, and dry cooling with seawater or circulation liquid is adopted for cooling an exhaust manifold and an exhaust pipe. High temperature of exhaust gas immediately after it is discharged from the engine makes sealing of bonding surfaces difficult, and in this example, though a gas channel, and a cooling water channel are separated, this structure has a problem of further increasing the weight.
In another example, indirect circulation cooling is adopted for cooling an exhaust manifold and an exhaust pipe, and sealability of bonded portions are ensured by widening the channel, but this structure has a problem that purification efficiency cannot be enhanced because a catalyst is located at a position distant from an engine exhaust port.
In the above-described Patent Document 3, indirect cooling with circulation cooling liquid is adopted for a portion up to the position of toe catalyst in the exhaust gas upflow region and indirect cooling with seawater is adopted for cooling exhaust pipes thereafter. However, not only the engine but also the portions corresponding to the exhaust manifold and the exhaust pipe are also indirectly cooled with the circulation liquid, and the catalyst is located at a position distant from the engine exhaust port. Accordingly, a large portion is a target of the circulation cooling, which necessitates a large heat exchanger.
Further, regarding particularly a muffler of the exhaust device, in Patent Document 4, since the portion from the catalyst to the muffler is disposed inboard, a large amount of air is necessary to cool this portion, and in addition, a large space is necessary for heat insulation, which has a problem that inboard residence and loading space becomes small. Further, a long distance cannot be reserved between the engine and the muffler, resulting in difficulty in decreasing the exhaust temperature, moreover, poor silencing performance.
Further, in Patent Document 5, the muffler portion has the dual structure and is water-cooled, which has a problem of an increase in weight, though the space can be reduced.
Further, in Patent Document 6, the exhaust gas is discharge in the air by the separate system during the idling operation, but in the outboard motor, it is not possible to set an exit of the separate system sufficiently high above the water. Consequently, the exit often sinks under the water during reverse drive and when the draft is deep, which makes it difficult to ensure stable performance during the idling operation. Further, for the same reason, there is a problem that it is not possible to set the catalyst sufficiently higher than the draft line.
Further, in Patent Document 7, since the exhaust gas is not discharged during the idling operation, it is necessary to increase the idling rotation speed in order to ensure stable idling performance, which necessarily worsens fuel performance and silencing performance. Another problem is that tilting occurs when a collision takes place with an obstruction in water, and it is difficult to alleviate an impact force.
Further, in the example of the wet in-air exhaust of the outboard motor among the other examples, the structure is compact and the inboard residence and loading space is large compared with the dry in-air exhaust, but the wetting water is beaten due to exhaust pulsation during the idling (deceleration) operation, and silencing performance becomes low.
Further, in the other example of the wet underwater exhaust of the inboard-outdrive motor, though silencing performance is high and the structure is compact, bellows of a main exhaust channel bends in accordance with steering and tilting of a propulsion unit. Consequently, durability and reliability of the bellows are low and in the worst case, water might flow inboard from the bellows.


In a Raman spectroscopy, the surface of metal film which is formed on a dielectric substrate in thickness of 50 to 200 nm and is characterized in that a plurality of fine holes satisfying the conditions defined by the following formulae are formed is caused to adsorb the material to be analyzed, light is projected onto the surface and the scattering light scattered by the surface is separated to obtain a spectrum of the scattering light,

1. Field of the Invention
This invention relates to a Raman spectroscopy method, a Raman spectroscopy system and a Raman spectroscopy device and more particularly to a Raman spectroscopy device for increasing Raman scattering.
2. Description of the Related Art
The Raman spectroscopy method is a method where a spectrum (Raman spectrum) is obtained by separating scattering light obtained by projecting light of a single wavelength onto a material and light (Raman scattering light) having a wavelength different from that of the projected light is detected. Since being very weak, the Raman scattering light is generally difficult to detect. However, it has been reported that the intensity of the Raman scattering light is increased to 104 to 106 when light is projected onto the material adsorbed on the surface of metal. Especially it has been known that when metal particles in the order of nanometers are distributed on the surface on which the material is adsorbed, the Raman scattering light is greatly increased. See, for instance, "Brilliant Optical Properties of Nanometric Noble Metal Spheres, Rods, and Aperture Arrays", Peter C. Andersen and Kathy L. Rowlen, Applied Spectroscopy, Volume 56, Number 5, 2002. The increase of the Raman scattering light is said to be due to local plasmon resonance. That is, it is said that strong electric fields are generated around metal particles when the free electrons in the metal particles vibrate resonating with an electric field of light, and the Raman scattering light is increased under the influence of the electric fields.

Raman spectroscopy method, raman spectroscopy system and raman spectroscopy device

Abstract: λ  =      a                                        (                              ɛ                                                                                1              ·              ɛ2                                            ɛ1            +            ɛ2                          )                    1        2            d<λ

Abstract: wherein λ represents the wavelength of the projected light, a represents the cycle of the fine holes, d represents the diameter of the fine holes, ε 1 represents the dielectric constant of the metal film and ε 2 represents the dielectric constant of the medium around the surface of the metal film.


A map update system includes: a navigation apparatus that provides guidance from a current position to a destination having been set based upon map data stored therein and downloads various types of information requested by a user; and a providing apparatus that provides the various types of information to be downloaded at the navigation apparatus, and: the providing apparatus transmits the various types of information and update information related to an update of map data to the navigation apparatus in response to a download request transmitted from the navigation apparatus; and the navigation apparatus issues a notice related to the update of the map data based upon the update information transmitted from the providing apparatus, while downloading the various types of information.

1. Field of the Invention
The present invention relates to a technology for updating map information stored in a navigation apparatus.
2. Description of Related Art
There is a method known in the related art that is adopted to update map data recorded in a hard disk drive (HDD) and used in an on-vehicle navigation apparatus (see Japanese Laid Open Patent Publication No. 2002-333323).

Map update system, navigation apparatus and providing apparatus


A highly efficient retransmission control method is achieved by preventing the order of data from being changed by one revolution of a modulo without adding extra overhead. The transmitting side continues to continuously transmit frames assigned frame numbers circulating by a modulo M to the receiving side. Upon detecting an error in the received frame, the receiving side returns a reject provided with the frame number of the frame. The transmitting side retransmits the frame to the receiving side in response to the reject. In a case where such retransmission control is carried out, the maximum number of times Nr a reject of the same frame is returnable is previously determined. The receiving side discontinues the return of the reject of the same frame until the number of times of the return exceeds the maximum number of times Nr. Consequently, the return of the reject of the same frame can be discontinued before the modulo of the frame number revolves once. As a result, it is possible to prevent the order of data from being changed by one revolution of the modulo.

1. Field of the Invention
The present invention relates generally to a retransmission control method, and more particularly, to a retransmission control method of performing error correction when a transmission error occurs in data by retransmitting the data.
2. Description of the Prior Art
A mobile/portable data communication service is one of the services whose demand toward realization has increased greatly in recent years, as represented by a word "Mobile Multimedia". A personal handyphone system (PHS) has been expected to be an infrastructure having a high bearer transmission rate, i.e., 32 kbit/s and being effective in realizing a multimedia in a radio environment. In order to realize data communication in a mobile communication environment which is lower in line quality than a wire circuit, an error control technique plays an important role. As an example of such an error control technique, a retransmission control method of an SR (Selective-Repeat) system has been conventionally proposed.
In the conventional SR retransmission control method, blocks are continuously transmitted even during a round trip delay period (RTD), and only a frame to which a reject (a retransmission request) is returned is retransmitted. Therefore, the receiving side has a buffer for preserving correct frames received after a frame including an error. If there is no error in a retransmitted frame, the receiving side outputs the retransmitted frame and the frames stored in the buffer to a user in accordance with the order of their frame numbers.
FIG. 12 illustrates a frame structure in the conventional SR retransmission control system. Portion (a) of FIG. 12 illustrates the structure of a frame for transmitting transmit data (hereinafter referred to as a transmit frame), and portion (b) of FIG. 12 illustrates the structure of a reject frame returned from the receiving side when an error occurs in received data or a retransmission wait timer times out.
As shown in portion (a) of FIG. 12, the transmit frame comprises a transmit data block 401, a frame number 402, an error-detecting code 403, and a synchronous flag 404 for frame synchronization. On the other hand, as shown in portion (b) of FIG. 12, the reject frame comprises a frame number 402, a reject code 405, and an error-detecting code 406 of a return frame. The transmission side divides the transmit data into a plurality of transmit data blocks 401, adds the frame number 402 to each of the transmit data blocks 401, then generates the error-detecting code 403 for making it possible to detect whether an error occurs in the data block or the frame number, and appends the error-detecting code 403 to the transmit data block 401. There are several methods of frame synchronization. A method of attaching a synchronous code with a particular bit pattern to the head of a frame is illustrated herein. Examples of the frame number include a modulo 8 (3 bits), a modulo 16 (4 bits), a modulo 32 (5 bits), a modulo 64 (6 bits), and a modulo 128 (7 bits). Generally speaking, the frame number of a modulo M starts with zero, is increased by one for each frame, and is returned to zero if it exceeds M-1, after which the foregoing is cyclically repeated.
FIG. 13 illustrates one example of transmission/receiving timing in the conventional SR retransmission control system. Portion (a) of FIG. 13 illustrates the timing of transmit frames and frame numbers, portion (b) of FIG. 13 illustrates the presence or absence of frame errors and return frames, portion (c) of FIG. 13 illustrates the timing of received frames and frame numbers, and portion (d) of FIG. 13 illustrates the frame numbers of data stored in a receive buffer.
In the specification, a frame assigned a frame number n shall be denoted by "frame (n)".
In the example shown in FIG. 13, an error occurs in frame (3), it is judged that there is an error in the frame (3) at the time where frame (4) is received, and a reject corresponding to the frame (3) is returned by a return frame. A round trip delay period (RTD) is a period corresponding to four frames. Since the round trip delay period deviates by a period corresponding to one frame in order to know the frame number of an error frame, however, a period corresponding to five frames (=RTD+1=4+1) is required until the return frame is returned to the transmission side. The transmission side continues to transmit new frames until it receives the reject with respect to the frame (3). As soon as the reject with respect to the frame (3) is received, the frame (3) is retransmitted. A case where an error occurs also in the retransmitted frame (3) is illustrated herein. The receiving side discards the received error frame or holds the error frame when it is later used for error correction, and eventually returns the reject with respect to the frame (3) again at the time where a time-out period (T.times.F) of a retransmission wait timer started from when the reject is returned has elapsed. The time-out period (T.times.F) of the retransmission wait timer is set to be longer than the round trip delay period (RTD). In the case shown in FIG. 13, the frame (3) reaches the receiving side without error upon being retransmitted twice. The receiving side adds data of the frame (3) to the heads of data of received frames (4) to (14) which have been stored in the buffer, and transfers the frames to a user.
As described in the foregoing, in the conventional SR retransmission control method, the new frames are continuously transmitted even during the round trip delay period (RTD), and only the frame having the reject returned is retransmitted. Even if a transmission line in which a long round trip delay period (RTD) is used, it is possible to perform efficient error correction.
FIG. 14 illustrates an example of retransmission control in a case where the round trip delay period (RTD) is a period corresponding to eight frames. FIG. 14 is the same as FIG. 13 except that the round trip delay period differs. In the case shown in FIG. 14, a modulo is 16 as in the case shown in FIG. 13. In the case shown in FIG. 14, a modulo of a transmit frame number revolves once before the second reject with respect to frame (3) reaches the transmission side. Therefore, a new frame (3) having the same frame number as that of the frame (3) which is the oldest frame which waits for retransmission on the receiving side is transmitted, and is received on the receiving side. In this case, the receiving side cannot judge whether the received frame (3) is a new frame or a retransmit frame. Thus, there occurs a situation where the receiving side adds data of the frame (3) to the heads of data of received frames (4) to (14) which have been stored in the buffer, and transfers the frames to the user regardless of the fact that the received frame (3) is a new frame. As a result, a row of data in which the order of data blocks is changed is handed to the user. It is considered that an identification bit for identifying a new or old frame is added, and the number of bits of the modulo is increased. In such a method, there arises another problem that the overhead of the frames is increased.
A method of calculating, on a network to which a plurality of terminals are connected, the number of times of retransmission Nr from a response wait period Tw and a retransmission interval Tr between the terminals and a transmission abandoning period Tk determined from the viewpoint of the response of the network is disclosed in Japanese Patent Laid-Open No. 252978/1994. In a method of calculating the number of times of retransmission which is disclosed in the gazette, the response wait period Tw is first calculated by the following equation (1): EQU Tw=K1.multidot.(Lf.multidot.Sg) (1)
K1: a coefficient of response wait time (K1>1) PA1 Lf: the maximum length of a data transmission frame (bit) PA1 Sg: an apparent transmission rate (bps) PA1 K2: a coefficient of a retransmission interval (K2.gtoreq.K1.gtoreq.1)
The foregoing equation (1) holds on the assumption that the apparent transmission rate varies due to the fact that the network is used upon being divided by the plurality of terminals, and a period required to transmit a data frame in a certain data amount at a decreased transmission rate is a response wait period. In such a case, a plurality of frames are not transmitted during the response wait period, so that the effect of the SR retransmission control is not obtained. Further, the modulo does not revolve once.
In the method of calculating the number of times of retransmission which is disclosed in the above gazette, the data retransmission interval Tr is calculated by the following equation (2), and the calculated data retransmission interval Tr, the transmission abandoning period Tk determined from the viewpoint of the response of the network, and the response wait period Tw are substituted in the following equation (3), to determine the number of times of retransmission Nr: EQU Tr=K2.multidot.(Lf/Sg) (2) EQU Nr=(Tk-Tw)/Tr (3)
The response of the network can be always held in a stable state by determining the number of times of retransmission in conformity with the varying apparent transmission rate, as described above.
An object of the invention which is disclosed in Japanese Patent Laid-Open No. 252978/1994 is to ensure the response of the network. It is not considered that the present invention is applied to prevention of one revolution of a modulo, not to speak of application to SR retransmission control.

Matsushita Electric Industrial Co., Ltd.


Systems and methods for determining whether a television is on and in as near proximity are provided. An example system includes a sensor, an analog-to-digital converter, and a digital signal processor. The digital signal processor processes a set of digital audio samples detected by the sensor to determine if the sensor is in near proximity to a television in an on state.

1. Field of the Invention
The present invention relates to apparatus and methods for determining whether a television is on and in near proximity to a sensor, and, more particularly, to apparatus and methods for determining whether a television audience member is in the same room as a television that is turned on.
2. Description of the Related Art
Television audience measurement systems are based either on portable devices carried by members of the audience, or on fixed devices placed in the vicinity of a television set. In both these applications, a microphone on the device picks up an audio signal associated with a television program. The usual objective is to determine the program or channel being viewed from an analysis of the audio signal. For example, in one approach, the device computes a "signature" for subsequent matching with a reference signature recorded at a central facility. Alternatively, in a second approach, the device extracts embedded identification codes that have been inserted into the audio stream at the broadcast facility, in order to identify the program.
One of the problems encountered by a portable device is to determine whether the audio signal picked up by the microphone is originating from a nearby television set. The microphone in such devices, being extremely sensitive, can respond to audio signals emitted in a neighboring room. There is a need to disregard such audio and process only the audio emanating from within a room in which the carrier of the device is present. In the case of the fixed device, it is essential to determine whether or not the television set is turned on or off.


A machine-implemented method of encoding/decoding data is described. The encoding method comprises steps of receiving a message of a given size, the message being represented by a series of units of data, configuring multiple encoding elements (50) in an arrangement having a given frame size, and encoding the message by passing each unit of data through the arrangement so that each unit is processed by at least one of the encoding elements. The frame size of the arrangement is the maximum number of units of data that can pass through the arrangement without any unit of data passing through the arrangement and being processed in the same way as another unit of data. The configuring of the arrangement defines how each unit of data is processed by the encoding elements and creates an arrangement corresponding to a frame size that is dependent upon the number of units of data in the series, for example so that the frame size of the arrangement is guaranteed to be greater than the number of units of data in the series.

In the field of internet and network security, there is a prevalent need for secure means of transmitting and sharing data between different parties, for example between content providers and content users. Encryption of data is a widely used technique for securing messages; however, as the sophistication of attacks increases, there is a growing need for increasingly complex encryption techniques, requiring large amounts of computer processing power.
Data is typically broken down into smaller blocks which are then processed in a way that encrypts the data. Many encryption methods of the prior art process similar blocks in the same way, leading to potential weaknesses in the system.
Certain methods of cryptography of the prior art use known protocols for encoding a message, where the only unknown parameter is the knowledge of a single secret, or private key. Once the private key is discovered by an eavesdropper, the encoded message may be decoded by the eavesdropper. Certain cryptography methods may be vulnerable to brute-force attacks, for example. There may be certain applications for encryption that require a greater level of security.
The use of complex variable, or reconfigurable networks of encoding elements which encrypt each message in a different way increases the challenge posed to attackers attempting to decode encrypted messages. However, complex, reconfigurable networks are likely to be computationally expensive and may not mitigate the security risks associated with repeating the same action on multiple parts of the message.
US2007/255941 describes a method of securing data sets that involves dynamically hopping amongst a variety of encryption protocols, in a manner determined by a reconfigurable logic array. This improves security of messages by encrypting each message in a different way, but may be computationally expensive. Similarly, U.S. Pat. No. 6,823,069 describes a programmable logic device for dynamically changing encryption algorithms.
The present invention seeks to mitigate one or more of the above-mentioned problems. Alternatively or additionally, the present invention seeks to provide an encryption method with increased security. Alternatively or additionally, the present invention seeks to provide an improved method of encoding data. Alternatively or additionally, the present invention seeks to provide an alternative encryption system.

Machine-implemented method of dynamically encrypting data


A security device detaches a combination electronic article surveillance (EAS) and radio frequency identification (RFID) tag (EAS/RFID tag), and includes a detacher (magnet) to selectively disengage a clutch release disposed in a first portion of the combination EAS/RFID tag, a near field circular microstrip antenna configured to electronically read information stored in a second portion of the combination EAS/RFID tag. The antenna encircles the detacher and reads information from the second portion of the combination EAS/RFID tag at a position relative to the detacher when the second portion of the tag is disposed at any angle relative to the detacher and only when the detacher is positioned to disengage the clutch release. As long as the portion of the EAS/RFID tag containing the clutch end mechanism is located over the detaching magnet, the RFID label is in a valid detection zone regardless of its orientation relative to the antenna.

1. Technical Field
This disclosure relates to the field of electronic article surveillance (EAS) and radiofrequency identification (RFID) tags and more particularly, to a RFID read antenna for a combination EAS and RFID tag.
2. Background of Related Art
The use of a combination EAS/RFID security tag offers an added benefit of inventory control capability along with the traditional anti-theft deterrence from the EAS technology. The combination EAS/RFID security tag may be attached to clothing items using a pin attachment mechanism. This attachment mechanism may be removed by a detacher that may employ a magnetic means to release the pin.
It is advantageous to read the RFID information when the pin is being removed. Furthermore, it may be of interest to enable the removal of the pin by first reading and verifying the RFID information.
To detach the pin of the combination EAS/RFID security tag, the user places the end of the tag in a defined center region of the detacher. It should be noted that the security tag may rotate about the detacher magnet region at any arbitrary angle. Therefore, the orientation of the RFID element with respect to the detacher center may be quite arbitrary. If the RFID element must be read in this position, then either the detachment orientation needs to be fixed in order to allow a fixed position RFID near-field antenna to read exactly at this fixed position or a new omni-directional RFID near-field antenna is needed.
Therefore, there exists a need for the development of an RFID read antenna which enables a combination EAS/RFID hard tag to be detached and read consistently and accurately at all times independently of the angle of the EAS/RFID tag relative to the RFID antenna.

This patent is subject to a terminal disclaimer.

Antenna for a combination EAS/RFID tag with a detacher


A contact probe for a testing head effective to test a plurality of semiconductor-integrated electronic devices comprises a rod-like probe body having a cross section of prefixed contour and provided in correspondence with at least one end with an eccentric contact tip. The contact tip is positioned within the contour of the cross section of the probe body.

1. Field of the Invention
The present invention relates to a contact probe for a testing head effective to test a plurality of semiconductor-integrated electronic devices comprising a plurality of so-called contact pads.
The invention particularly, but not exclusively, relates to a testing head having vertical probes for testing semiconductor-integrated electronic devices and the following description is made with reference to this field of application for convenience of illustration only.
2. Description of the Related Art
As it is well known, a testing head is essentially a device effective to electrically interconnect a plurality of contact pads of a semiconductor-integrated electronic device with corresponding channels of a testing machine which performs the test thereof.
The test carried out on integrated electronic devices is effective to detect and isolate devices already faulty during the manufacturing step. Normally, testing heads are thus used for the electric test of the semiconductor-integrated electronic devices, or integrated on a silicon wafer, before cutting and assembling the same inside a package for containing chips.
The connection between the testing apparatus and the contact pads of the tested integrated electronic device being tested is carried out by using a plurality of contact elements or probes.
In particular, these contact probes are normally made of wires of a special alloy having good electrical and mechanical properties.
The good connection between the probes and the contact pads is also ensured by the pressure of each contact probe on the respective contact pad.
A testing head having vertical probes comprises at least a pair of dies or plate-like parallel holders placed at a certain distance from one another in order to leave an air gap as well as a plurality of contact probes.
Each plate-like holder, called die in the technical field here considered and hereafter in the description, is provided with a respective plurality of through-going guide holes, each hole in one of the dies corresponding to a hole in the other die, wherein a respective contact probe is slidingly engaged and guided. In particular, the movable contact probes elastically flex inside the air gap between the two dies.
Testing heads of this type are commonly called "vertical probes".
As schematically shown in FIG. 1, a testing head 1 of the known type comprises at least an upper die 2 and a lower die 3, having respective upper 4 and lower 5 through-going guide holes wherein at least one contact probe 6 is slidingly engaged.
The contact probe 6 has a contact end or tip 7. In particular, the contact tip 7 is in mechanical contact with a contact pad 8 of an integrated electronic device to be tested, performing at the same time the electrical contact between said device and a testing apparatus (not shown) of which this testing head is a terminal element.
The upper 2 and lower 3 dies are suitably spaced from an air gap 9 which allows the deformation or inclination of the contact probes 6 during the normal operation of the testing head, i.e. when this testing head comes into contact with the integrated electronic device to be tested. Moreover, the upper 4 and lower 5 guide holes are sized in order to guide the contact probe 6.
FIG. 1 schematically shows a testing head 1 having loose-fitting probes associated with a micro-contact strip or space transformer, globally indicated with 10.
In this case, the contact probes 6 have a further contact tip towards a plurality of contact pads 11 of the space transformer 10, the good electrical contact between probes and space transformer 10 being ensured in a similar way to the contact with the integrated electronic device to be tested through the pressure of the probes 6 on the contact pads 11 of the space transformer 10.
A very felt problem in the specific technical field is that of the reduction of the distance which separates the contact pads 8 of the device being tested, this distance being known in the field as "pitch".
In particular, the technological development and the miniaturization of the chips requires the continuous reduction of the pitch of the integrated electronic device to be tested, and thus the distance between two adjacent probes 6 of the testing head which performs the test thereof.
The minimum pitch depends on the geometrical conformation and on the sizes of the probes 6, according to the relation:Pitch min=E+2A min+W min
being A min=(F−E)/2
Where, as illustrated in FIG. 2 which shows a section view of a part of the testing head 1 according to the prior art:
Pitchmin is the minimum pitch, i.e. the minimum distance between the centers of two adjacent contact pads 8 of the integrated electronic device to be tested;
E is the value of the cross section axis of the probe 6.
Wmin is the minimum value of the wall thickness between a guide hole 4 and 5 and the subsequent, such as to guarantee a certain mechanical strength to the structure of the testing head 1; and
F is the value of the cross section axis of the guide hole 4.
In the current vertical technologies, normally using probes having circular cross section, a reduction of the pitch value is obtained by reducing the size of the probe 6, in particular their minimum axis E (corresponding to the minimum diameter in the case of probes having circular section), being the other factors of the preceding relation practically fixed by the technological limits of realization of the testing heads.
This solution collides with the need of using probes 6 having sufficiently high section, able to guarantee a strength of the contact carried out by means of these probes, still miniaturizing the contacts.
Moreover, most integrated devices have contact pads arranged on all the four sides of the device to be tested. In this case the arrangement of the probes in correspondence with the device angles is to be taken into account, so as to avoid the contact with one another which would invalidate the outcome of the test performed.
It is known from the Italian patent application No. MI2001A000567 filed on Mar. 19, 2001 in the name of Technoprobe S.r.l., as well as from the corresponding European patent application No. 1 243 931 of Mar. 15, 2002 and from the corresponding U.S. patent application Ser. No. 10/102,449, now issued U.S. Pat. No. 6,768,327, to realize contact probes for testing heads provided with a rigid arm laterally projecting from a probe body, as schematically shown in FIG. 3.
In particular, the testing head 30 shown in FIG. 3 comprises an upper die 12A and a lower die 12B having respective guide holes 13A and 13B effective to house a contact probe 14.
The contact probes 14 have contact tips 15 intended for abutting on a plurality of contact pads 16 of an integrated electronic device to be tested, schematically indicated with 17.
The testing head 30 shown in FIG. 3 comprises loose-fitting probes having a further end 18 in contact with a micro-contact strip or space transformer 19.
A rigid arm 20 extends along a direction being perpendicular or sloping of a suitable angle with respect to the probe 14, i.e. it has an axis B-B being perpendicular or sloping with respect to an axis A-A of the contact probe 14, and it ends with the contact tip 15 of the probe 14 for the contact pads 16 of the integrated electronic device 17 to be tested.
In this way, the contact between the tip 15 of the probe 14 and the pad 16 is spaced of a value Z with respect to the axis A-A of the contact probe 14 itself thus allowing to reduce the value of the minimum pitch of the contact tips 15 and making it possible to test integrated electronic devices with contact pads 16 with close contact centers C, i.e. reduced pitches, Z being the distance between the axis AA and a parallel axis passing through the contact center C of the probe.
Although advantageous under several aspects, the testing head 30 realized according to the prior art has different drawbacks.
The first among all stays in the need of deforming the probe body 21 so as to realize the rigid arm 20. The method for realizing the contact probe has thus to provide a deformation step which must be very precise and repeatable, in order to guarantee the fittingness of all the probes belonging to a same testing head.
Beside adding a critical step to the method for realizing the contact probes, this deformation introduces weakness elements in the body 21 of the probe itself.
Moreover, the total space of the contact probe thus realized suffers from the longitudinal size D introduced by the rigid arm 20.

Testing head contact probe with an eccentric contact tip


An elementary antenna includes a planar radiating device comprising a substantially plane radiating element and a transmit and/or receive circuit comprising at least one amplification chain of a first type and at least one amplification chain of a second type, each amplification chain of the first type being coupled to at least one excitation point of a first set of at least one excitation point of the radiating element and each amplification chain of the second type being coupled to at least one point of a second set of points, the excitation points of the first and second set being distinct and the amplification chain of the first type being different from the amplification chain of the second type so that they exhibit different amplification properties.

A so-called array antenna comprises a plurality of antennas that may be of the planar type that is to say of the printed circuit type and often called patch antennas. The technology of planar antennas makes it possible to produce slender, directional antennas by producing the radiating elements by etching metallic patterns on a dielectric layer furnished with a metallic ground plane at the rear face. This technology leads to very compact directional electronic-scanning antennas that are simpler to produce and therefore less expensive than Vivaldi-type antennas.
An active antenna conventionally comprises a set of elementary antennas each comprising a substantially plane radiating element coupled to a transmit/receive module (or T/R circuit for "Transmit/Receive circuit"). Each transmit/receive circuit is linked to an excitation point. Each transmit/receive circuit comprises, in electronic warfare applications, a power amplification chain which amplifies an excitation signal received from centralized signal-generating electronics and excites the excitation point as well as a low noise amplification chain which amplifies, in receive mode, a reception signal, of low level, received by the radiating element at the level of the excitation point and sends it to a concentration circuit which sends it to a centralized acquisition circuit.
Array antennas of this type exhibit a certain number of drawbacks. Indeed, the low noise amplification chains exhibit different optimal input impedances from the optimal output impedances of the power amplification chains. Usually, the impedance of the excitation points is adjusted to 50 Ohms, since the instrumentation equipment is provided for this impedance. However, this is not the optimal impedance for HPA power amplifiers (with reference to the expression "High Power Amplifier") or for LNA low noise amplifiers (with reference to the expression "Low Noise Amplifier"). To alleviate this drawback, it is customary to dispose an impedance transformer at the output of the power amplification chain and at the input of the low noise amplification chain. This transformer leads to less good efficiency in transmission, giving rise to significant energy losses resulting in thermal dissipation. It also leads to a less good noise figure NF in reception, the signal-to-noise ratio of the received signal being degraded.
One might be required to transmit signals exhibiting different powers by means of one and the same array antenna. One may for example transmit high-power so-called radar signals exhibiting a narrow frequency spread band (of the narrowband type i.e. 10 to 20% of the central frequency) and telecommunication, or radar jamming, signals exhibiting a wide frequency spread band (of the wideband type whose spread band may be up to three octaves) and a lower power. These signals may be transmitted simultaneously or in a sequential manner. A planar radiating device in MMIC (for "Monolithic Microwave Integrated Circuit") technology is for example known, comprising a transformer produced in the MMIC and enabling these two types of signals to be amplified in terms of frequency and power as a function of the spread bandwidths and of the powers required and enabling them to be summed before injecting them onto an antenna at one and the same excitation point.
This solution exhibits drawbacks however. This type of transformer with signal summator integrated upstream of the radiating element, in the MMIC, is voluminous and gives rise to significant energy losses. In order to limit the heating of the integrated circuit, it is indispensable to cool it, thus requiring specific equipment and involving significant energy consumption.

Elementary antenna comprising amplification chains for delivering signals to and amplifying signals arising from a planar radiating device thereof

CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE