A method of generating caption abstract, including: generating a target text from a predetermined caption, analyzing a morpheme of a word included in the target text, and analyzing a grammatical structure of the target text by referring to the morpheme; extracting and removing low content words from the target text by using the morpheme or information on the grammatical structure and determining a main predicate; extracting a major sentence component with respect to the main predicate by referring to the information on the grammatical structure, as a candidate abstract word; substituting a relevant word for a complex noun phrase or a predicate phrase from the candidate abstract words by referring to a predetermined database; and generating an abstract by rearranging the candidate abstract words according to a predetermined rule.

1. Field of the Invention
The present invention relates to a data summarization method and apparatus, and more particularly, to a method and apparatus for generating a suitable abstract by analyzing a morpheme and grammatical structure of a caption.
2. Description of the Related Art
Due to development of data compression and data transmission technologies, an increasing amount of multimedia data is being generated and transmitted. Due to a large number of multimedia data capable of being accessed on Internet, it is very difficult to retrieve desired multimedia data. Also, many users want to receive only important information in a short time via an abstract of data, which is made by summarizing multimedia data. In response to requests of users, there are provided various methods of generating an abstract of multimedia data. From the methods of generating an abstract of multimedia data, there is a method of generating an abstract by extracting a noun from closed caption text. However, the abstract generated by extracting a noun is too long and is not refined to be provided to users. Also, since there is no context because of extracting only a noun, a meaning of the abstract cannot be precisely conveyed. For example, when extracting only a noun from closed caption text such as "It was confirmed the artificial fish reef that was installed in order to protect marine resources cannot do its job", awkward abstract content is extracted such as "fish reef, resources, and job".
Also, in a conventional method of generating an abstract by recognizing a caption added to video data, since a caption has to be directly recognized and processed from video data, an amount of data that has to be processed to generate the abstract is increased. Also, since a caption included in the video data is generally made to be condensed in order to convey content together with the video data, a text of the caption may not precisely reflect the content.
Accordingly, a data summarization method and apparatus capable of generating a natural abstract by extracting an abstract word by reflecting a morpheme of a text included in a closed caption, grammatical structure, a meaning of a word, and rearranging the extracted abstract words in a form suitable for recognition are required.


A wearable alert device includes an audio transducer and driver circuit that allows selection of either a high or low volume setting for driving the transducer. The driver circuit is operable in a single ended mode for low volume and a double ended mode for high volume. The single ended mode holds one terminal of the transducer low while the other is driven in correspondence with a clock signal, while the double ended mode drives one terminal in correspondence with the clock signal and the other terminal is inverted from the clock signal. The transducer is activated in response to an alert event, and can be driven according to a profile or pattern.

Alert devices have been in use for some time, and are typically used with a proprietary base unit. These devices can be worn, such as in the form of a necklace, and typically have a button that can be pressed by the user, causing the device to send a signal to the base unit. The base unit is usually connected to a phone line to place an automated call to a monitoring agency, which charges a fee for the monitoring service. Given the limited functionality of these devices, they are typically only used for medical emergencies or other situations where the user is unable to help themselves. Conventional alert devices, however, are one way devices. That is, they only transmit a signal to the base unit. Furthermore, they have a limited range since the base unit is not moveable.
More recently, some manufacturers have developed wearable devices that can connect with mobile communication device using, for example, the BlueTooth protocol. When these devices are connected to each other wirelessly, they are "paired." These devices, however, tend to be fairly sophisticated. They often include, for example, a graphical display for visually displaying information. Essentially they are scaled-down version of the mobile device with which they are paired, providing limited access to resources on the mobile communication device. As a result, they can be somewhat expensive, as well as complicated to use for simple alert applications.
Accordingly, there is a need for a wearable alert device that can be paired with a mobile communication device that can be used to both receive alert messages and alert the user, as well as to send alert events to the mobile communication device that can accomplish these goals without the expense of devices that merely replicate functions of the mobile communication device.
Those skilled in the field of the present disclosure will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein. Well known elements, structure, or processes that would be necessary to practice the invention, and that would be well known to those of skill in the art, are not necessarily shown and should be assumed to be present unless otherwise indicated.

Wearable alert device having selectable alert volume and method of operating same


An electrophoretic display apparatus driving method that allows DC balance to be achieved and reduces variations in size and color tone of a displayed image that may occur in a partial-screen drive method and related apparatus are provided. The drive method includes a first image display step (S2) of displaying a first image in a first color on a display section, a first image adjustment step (S3) of displaying a background of the first image in a second color, a first image deletion step (S4) of displaying the background of the first image in the first color, a second image display step (S12) of displaying a background of a second image in the second color, a second image adjustment step (S13) of displaying the second image in the first color, and a second image deletion step (S14) of displaying the second image in the second color.

1. Field of the Invention
The present invention relates to a method for driving an electrophoretic display apparatus, an electrophoretic display apparatus, an electronic apparatus, an electronic timepiece, and other related apparatus and methods.
2. Background Information
In recent years, a display panel having a memory capability that can hold an image even when the display panel is powered off has been developed and used in an electronic timepiece and other apparatus. Known examples of the display panel having a memory capability include an EPD (electrophoretic display) and a memory-capable liquid crystal apparatus.
An electrophoretic display apparatus has excellent advantages, such as a wide angular field of view, a high contrast ratio, high flexibility, and low power consumption because an electrophoretic display apparatus is a reflective display.
On the other hand, as described in JP-T-2005-530201 (Patent Literature 1), the operating life of an electrophoretic display apparatus may be shortened if the time average of an electric field applied between electrodes in the apparatus is not nearly zero. That is, to ensure long-time reliability of an electrophoretic display apparatus, it is necessary to achieve DC balance or to make the time average of the applied electric field nearly zero.

Method for driving electrophoretic display apparatus, electrophoretic display apparatus, electronic apparatus, and electronic timepiece


Ripple counter circuits in integrated circuit devices can have fast terminal count capability. A terminal count circuit can be configured to mask selected unstable counter bits generated by a ripple counter circuit using an indication that a terminal state of the ripple counter circuit has been reached. Related methods are also disclosed.

Asynchronous ripple counter circuits are known to be used, for example, as frequency divider circuits. Some asynchronous ripple counter circuits include a number of synchronous state devices (such as flip-flops) connected in series so that the data output of each stage is connected to the clock input of the following stage. The asynchronous ripple counter circuit is typically driven by a clock signal, provided to the first stage or least significant bit (LSB), of the ripple counter circuit. Accordingly, the output of each of the flip-flips operates at a frequency that is one half of the frequency of the output of the preceding stage of the counter. For example, the output of the first stage (LSB) of the ripple counter transitions once in response to two transitions of the clock signal input. Similarly, the second order bit of the counter transitions once for every four transitions of the input clock signal. For this reason, asynchronous ripple counter circuits are sometimes referred to as frequency dividers. Asynchronous ripple counter circuits are further discussed, for example, in U.S. Pat. No. 5,060,243 to Eckert.
It is known that as the number of bits included in an asynchronous ripple counter circuit is increased, there is an increased likelihood that the more significant bits in the counter circuit will remain unstable for an extended period after each clock transition at the input of the counter circuit. In particular, the more significant bits of the asynchronous ripple counter circuit may transition through several intermediate states before reaching a final correct state (which actually reflects the number of clock transitions input to the ripple counter circuit). It is further known that as the frequency of the clock signal applied to the asynchronous ripple counter circuit increases, the likelihood that the more significant bits of the counter circuit will be unstable for periods subsequent to a clock signal transition also increases. As such, asynchronous ripple counters may not be suitable for high frequency applications.

Ripple counter circuits in integrated circuit devices having fast terminal count capability and methods of operating the same


A test element (10) used to determine concentration levels of free and total chlorine in a water sample comprises a test pad (12) adhered to a substrate (14), wherein the test pad (12) is impregnated with a stabilized DPD solution. The test pad (12) is color responsive to different concentration levels of chlorine in the water and compared to a color chart to determine the level of free chlorine and/or total chlorine in the water. The stabilized DPD solution may include N,N-diethyl-p-phenylenediamine oxalate salt, a polymeric anhydride such as a methyl-vinyl anhydride and an organo-sulfate such as dimethylsulfone.

The DPD (N,N-diethyl-p-phenylenediamine) method for testing chlorine levels was introduced in 1957, and has become the most widely used method for determining free and total chlorine in water. The test has always been used as a liquid test and not developed as a reagent strip for dipping and reading the color by comparing it to a color chart. Current tests in the market that are called DPD strip tests are merely transfer tests not for dip-and-read.
Two standard DPD colorimetric methods are generally recognized in the international community and approved by most states for testing pools and spas. DPD test methods are based on liquid test kits that involve mixing a sample of pool water with chemicals dispensed from a dropper bottle and reading the color developed with a photometer. Those that are currently called DPD test strips have DPD powder attached to a paper or plastic strip/stick. The strip is dipped in a tube of water collected from a pool or spa allowing the powder to dissolve in the water sample and react with any chlorine to give a pink color. The developed color is then read by comparison to a color chart, or on a colorimeter or photometer type device. In essence, the strip-type device is merely a transfer agent for the DPD powder. Each of the U.S. Pat. Nos. 7,491,546; 7,333,194; and, 6,004,820 disclose delivery-type devices, not dip-and-read test strips.
Some prior art (U.S. Pat. Nos. 3,937,613 and 4,275,031) describe reagent delivery devices that include inert plastic strips that are rigid enough to release the reagents by stirring the stick and reading the pink color with a photometer. In U.S. Pat. No. 4,275,031, Fisher et al. describe the use of polyvinyl alcohol (PVA) as an embedding polymer for DPD sulfate and waiting for ten minutes instead of immediate reading. Supposedly, the PVA dissolves in the sample and releases the DPD sulfate suggesting the PVA is an embedding polymer that retards the release of the DPD sulfate. Again, the color developed is read by use of a hand-held color reading device. The transfer agent can be of variable thickness or texture, but it must be able to deliver enough analytical reagent for immediate photometric analysis of free chlorine with accuracy. What is needed is a more stable formulation of DPD for use on test strips.

Chlorine analytical test element and a stabilized N, N-diethyl-p-phenylenediamine solution


An ink-jet printer is provided capable of performing a printing operation across the entire width of a recording medium such as a tape without producing a non-printed area at edges of the recording medium. In the ink-jet printer, the printing position is defined by an guide element disposed so that the guide element faces an ink-jet print head. The guide element is provided with excess ink capturing apparatus having a mesh screen with a size greater than the width of the tape being carried, and also provided with an ink absorbing surface disposed at the back of the above-described screen. To perform a solid printing operation onto the tape, the printing range is set greater than the tape width without producing a non-printed area at the edges. The ink droplets which are ejected from the print head when the print head is located in regions outside the tape are all absorbed into an ink absorber via the mesh screen disposed at the surface of the guide element thereby enduring that the surface of the tape is not dirtied with ink.

Various types of ink-jet printers are known in the art. In these types of printers, maximum printing areas are defined for individual standard sizes of recording media. In general, the maximum printing area is defined in terms of top-, bottom-, right- and left-margins so that the printing area is smaller than the size of a recording medium by the amount defined by the margins. Each margin is set to a value in the range from 3 mm to 13 mm, and no printer has been proposed which can perform a printing operation in an area including the end portion of the recording medium.
Furthermore, in another known small-sized ink-jet printer, a tape having a color selected from various colors can be employed as the recording medium, and color printing can be performed onto the selected tape. In the small-sized ink-jet printer of this type, a color printing operation is performed onto a tape with inks supplied to ink-jet print heads from ink tanks for color inks of cyan (C), magenta (M), and yellow (Y).
As for the tape, it is known to provide a tape which has a releasable sheet covering the back surface of the tape via an adhesive layer. After completion of printing, the tape is cut into a piece having a proper size. Then the releasable sheet is removed and the tape is affixed to a desired object. The printer of the type designed to perform a printing operation onto this type of tape is called a label printer or label word processor and is now popular in the market.
However, when the conventional ink-jet printer is used to perform a solid printing operation across the entire area of a recording medium such as a tape, there occurs a problem in that a non-printed area is produced at an end portion of the width of the tape.
To perform a solid printing operation by moving a print head in a reciprocating fashion across the width of a tape without producing a non-printed area at the edges of the tape, it is required to start a printing operation at one end of the width of the tape and stop the printing operation at the other end of the width of the tape.
However, it is generally difficult to precisely drive the print head so that the printing operation is started precisely at one edge of the width of the tape and is stopped precisely at the other edge of the width of the tape. This difficulty arises from a slight deviation in the tape carrying position in a direction across the width of the tape, or from a timing error between the ink ejection operation and the reciprocating movement of the print head.
If the printing operation is not controlled precisely, a non-printed area is produced at a region near the edge of the width. This could occur, for example, if the start of the printing operation is delayed from the time at which the print head is at the edge of the width of the tape.
In view of the above, it is an object of the present invention to provide an ink-jet printer capable of performing a printing operation for a limited area at an edge of the width or the entire area of the tape without producing a non-printed part in the selected area, or across the entire width or along the entire length of the tape without producing a non-printed part in the selected direction (hereafter, these printing operation modes are represented by a generic term "solid printing mode").
Furthermore, it is another object of the present invention to provide an ink-jet printer that does not make a recording medium dirty with ink droplets which are deposited on a guide element or the like during a solid printing operation.
It is a further object of the present invention to provide a recording medium suitable for use with an ink-jet printer capable of performing a solid printing operation.
To achieve the above objects, the present invention provides an ink-jet printer in which a print head is controlled so as to make possible performing a printing operation in an area which is deviated outward from the leading or trailing edge or either side of a recording medium such as a tape being carried (this printing operation will also be referred to as a "passing-over" printing operation). With this arrangement, the print head is driven in such a manner that the printing operation is performed continuously until the print head has moved past the edge of the width of the length of the recording medium thereby accomplishing the solid printing operation without producing a non-printed area at the end portion of the recording medium.
Furthermore, in addition to the above construction, the ink-jet printer of the present invention also has excess ink capturing means for capturing the ink droplets which are ejected from the print head when the print head is at a passing-over position. According to this technique, it is possible to avoid the deposit of the ejected ink droplets onto the guide element disposed facing the print head and thus it is possible to prevent the following recording medium from being dirtied with the deposited ink.
More specifically, according to an aspect of the present invention, there is provided an ink-jet printer comprising: a recording medium supplying source; a carrying path along which a recording medium supplied from the recording medium supplying source is carried; recording medium carrying means for carrying the recording medium along the carrying path; an ink-jet print head disposed on the carrying path, the ink-jet print head being adapted to move in a reciprocating fashion along a first direction relative to the recording medium to be carried; ink supplying means for supplying ink to the print head; and printing operation control means having the capability of setting the printing range of the print head in the first direction so that the printing range includes a region outside the edge of the recording medium.
In the above-described ink-jet printer, the printing range in the first direction, that is the range in which a solid printing operation is possible, is for example a direction across the width of the recording medium perpendicular to the carrying direction along which the recording medium is carried. Alternatively, the first direction may be a direction along the length of the recording medium parallel to the carrying direction along which the recording medium is carried. Furthermore, it is also possible to set the printing range in such a manner that, in addition to the first direction, the printing range also includes an area which is deviated outward from an edge of the recording medium in a second direction different from the above first direction. For example, if the first and second directions are selected so that they are perpendicular to each other, it is possible to accomplish a solid printing operation over the entire area of a recording medium.
In another aspect of the invention, the ink-jet printer further includes excess ink capturing means for capturing the ink droplets which are ejected from the print head when the print head is located at a position deviated outward from the edge of the recording medium.
The above-described excess ink capturing means is disposed at a location facing the printing head via the carrying path, and the excess ink capturing means is formed over the entire range including the printing range of the print head, wherein the printing range includes an area outside the edge of the recording medium. To achieve such a construction, the excess ink capturing means is disposed on a guide element which defines the position of printing performed by the print head onto the recording medium being carried. In this case, the surface of the guide element facing the recording medium can be formed of a stainless steel mesh.
Furthermore, it is desirable that the excess ink capturing means include ink exhausting means for exhausting captured ink thereby preventing the excess ink capturing means from becoming full of the captured ink and thus maintaining the capability of capturing excess ink droplets.
In the case of an ink-jet printer for performing a printing operation onto a large-size recording media, it is not economical to dispose the excess ink capturing means across the entire width or along the entire length. The above problem can be avoided if the excess ink capturing means is adapted to move in one piece with the print head. This construction may also be applied to a small-size recording medium.
A tape having a great length and having a constant width can be employed as the recording medium. In this case, a tape cartridge can be employed as the recording medium supplying source in which the tape, wound in the form of a roll, is accommodated wherein the tape cartridge is adapted to be removably mounted in the main part of the ink-jet printer.
In this case, the tape cartridge can accommodate various tapes having different widths. Therefore, to make it possible to correctly set the printing range of the solid printing operation corresponding to the width of a tape used, the tape cartridge further includes width indication means for indicating the width of the tape accommodated in the tape cartridge; the printing operation control means includes reading means for reading the width indicated by the width indication means; and the printing range of the print head in the first direction is set according to the width read by the reading means so that the printing range includes an area outside the edge of the recording medium.
Furthermore, a transparent medium such as a transparent tape may be employed as the recording medium.

Ink-jet printer for printing across an entire surface of a recording medium


The present invention discloses a halo test method for an optical chip in an integrated circuit. A captured image array is processed as a circle by: dividing the array into circular patterns on the basis of the radius, reconstructing the circular patterns into a two-dimensional array according to coordinates, and then performing corresponding operations on the obtained array to obtain a desired value. By the halo test method for an optical chip in an integrated circuit provided in the present invention, without increasing any extra hardware cost and under the primary test conditions, the technical problem in the prior art that there is no well-developed method and algorithm for testing halo on a fingerprint on display (FOD) chip is solved.

In the prior art, in order to test halo on an optical chip in an integrated circuit, generally, the light-sensing array of the chip is irradiated by vertical and uniform light. Each pixel output is uniformly distributed. Due to the chip's own characteristics, pixels in the middle have high light sensitivity and pixels at the edge have low light sensitivity. FIG. 1 shows an image restored from the captured data by an FOD chip in a 208*160 array. In a conventional test, after capturing the data of the array, a mean value of the image and a mean value of rows/columns are calculated by the present well-developed algorithms to find any bad row/column, bad point in the image, shading (with great difference in luminance), etc. Those detection methods or algorithms are all based on rows, columns, points and blocks of the array. Halo may appear on FOD chips in certain faults or conditions. Pixel units with halo do not have a maximum or minimum value in a row, column or region. Therefore, by those algorithms, it is unable to detect the halo fault. The halo test method for an optical chip in an integrated circuit, as provided in the present application, is intended to solve this problem in halo test.

Halo test method for an optical chip in an integrated circuit


A coarse reference ladder provides a plurality of coarse references. A coarse ADC receives an input voltage. The coarse ADC performs a first comparison of the input voltage and the plurality of coarse references and outputs a coarse output. A switch matrix is configured to close a switch based on the coarse output. An input line corresponding to a coarse reference is coupled to the switch matrix. The input line is precharged to the input voltage. The input line settles from the precharged input voltage to the coarse reference. A fine reference ladder provides a plurality of fine references based on the coarse reference. A fine ADC receives the input voltage and performs a second comparison of the input voltage and the plurality of fine references and outputs a fine output. Logic outputs a digital output for the input voltage based on the coarse output and the fine output.

The present disclosure generally relates to analog-to-digital converters (ADCs) and more specifically to reference pre-charging for ADCs.
Unless otherwise indicated herein, the approaches described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
A two-step subranging ADC architecture performs an analog-to-digital conversion in two steps. FIG. 1 depicts a conventional two-step subranging ADC architecture 100. Architecture 100 includes a coarse ADC 102 and a fine ADC 104. Coarse ADC 102 includes a coarser or poorer resolution than fine ADC 104 and can quickly determine an approximate subrange that a sample of an input analog signal falls within. This narrows the range of analog voltages in which the sample of the input analog signal may correspond. Fine ADC 104 then further defines the analog voltage from within the subrange selected by coarse ADC 102.
The input analog signal is received at a track-and-hold stage (T/H) 106. Track-and-hold stage 106 tracks the input analog signal and stores an input voltage for the sample of the input analog signal. For example, the input analog signal may be sampled for a half clock cycle and the input voltage from the sample is stored for another half clock cycle.
Coarse ADC 102 compares the stored voltage to a plurality of coarse references received from a reference ladder 108. Reference ladder 108 may include a plurality of tap points. Each tap point may be at a different voltage level for each coarse reference. Coarse ADC 102 performs a first comparison of the input voltage to the coarse references to determine a subrange in which the input voltage falls within.
A result of the first comparison is then used to select finer references or finer subdivisions of the selected subrange for fine ADC 104. For example, certain switches in a switch matrix 110 are closed to provide a second subrange of fine references to fine ADC 104. Fine ADC 104 then performs a second comparison of the fine references and the input voltage.
Encoding and digital correction logic 112 uses the results of the first comparison and the second comparison to determine a first digital code and a second digital code. The first and second digital codes are used to determine a digital output for the sample of the input analog signal. For example, the first and second digital codes may be appropriately weighted, error corrected, and combined to generate the digital output, which may be a digital representation of the sample of the input analog signal.
The determination of the first digital code and second digital code each needs to be made within a half clock period, T/2, where T is a clock period. When the sampling rate goes up, the time that coarse ADC 102 needs to make a decision becomes a larger part of its half clock period T/2.
Reference ladder 108 needs time to settle from a voltage level of a previous sample to set up the fine references. FIG. 2 shows a timing diagram for the conventional two-step subranging architecture 100. At each clock cycle, the input analog signal is tracked (T) and held (H). During the hold period, coarse ADC 1-102 makes its decision within a portion of the T/2 period. Then, in the remaining part of the same T/2 period, coarse output encoding, fine reference selection and subsequent setting of the fine reference takes place. When the sampling rate goes up, coarse output encoding, fine reference selection and subsequent setting of the fine reference combined together take a longer part of the T/2 period, which means less time for reference settling is allotted.
The first digital code from coarse ADC 102 is used to select the switches in switch matrix 110. This reproduces a quantized version of the analog input sample that is used to determine the fine references. For example, the quantized version is the input voltage plus a quantization or rounding error. The output of the switch matrix needs to settle to the voltage of the quantized version. The settling time may become a speed bottleneck as ADC resolution and conversion speed become higher due to large loading from the number of switches and comparators in coarse ADC 102 and fine ADC 104.
FIG. 3 depicts a waveform of a conventional method of precharging using architecture 1-100. At 302, the voltage at the output of switch matrix 1-110 is V1, which is the quantized voltage of the previous sample. At 304, coarse ADC 1-102 is strobed. Then, coarse ADC 1-102 performs the comparison as discussed above. At 306, the switches in switch matrix 1-110 are selected based on the first digital code that was determined. The voltage level needed to set up the fine references is a voltage V2 shown at 308. At 310, a fine reference settling time is needed to move the voltage level from V1 to V2 (ΔV). When the last sample was at a significantly different voltage level as the current sample, a large amount of time is dedicated to fine reference settling to move the voltage from V1 to V2.

Reference pre-charging for two-step subranging ADC architecture


A compact sweeping vehicle has steerable front wheels of variable track with a minimum track dimension for sweeping and a maximum track dimension for travel to and from the workplace. The front wheels are steerable and independently driven by hydraulic motors and are each supported on extendable parts of a telescopic axle beam which is supported on trailing arms supported by ball joints from the chassis of the vehicle. The extendable parts are extended and retracted by track change cylinders and steering is by a hydraulic cylinder extending between the axle beam and a steering arm of a bell crank lever for one of the wheels, which is connected by a forwardly extending drag link to a bell crank forming part of a steering relay mechanism which is connected by a cross link to a second bell crank lever, one arm of which is connected to a rearwardly extending drag link to a steering arm of the other wheel.

1. Field of the Invention
This invention relates to a sweeping machine with variable wheel tracking.
Small compact sweeping machines are well known in the marketplace and comprise a four-wheeled vehicle with a cab at its front end behind which is a rubbish hopper capable of taking up to about a ton of rubbish or other material, the machines having steerable front wheels controllable from the cab and a pair of contra-rotating brushes extending forwardly in front of the cab and easily visible to the operator within the cab. The brushes are able to sweep a width varying from about 1 meter to 2 meters, the width of which is again controllable from within the cab. The machines are normally provided with a suction arrangement to pick up rubbish swept to a central location between the contra-rotating brushes and with some form of dust separation equipment to separate out dust from the exhaust air stream from the suction arrangement. The machines may be provided with other operator comforts such as full suspension, electronic control systems for reduced operator workload, heated windscreen, adjustable steering wheel, adjustable driver's seat, a forward tilting cab and air conditioning. It is also important that the machine has excellent operator visibility. In order to improve rear vision, a reversing camera may also be provided. It is also preferable to provide the machines with four-wheel drive to improve stability in wet conditions and for good kerb climbing.
2. Description of Related Art
The machine of the present invention is of the compact type and accordingly it needs to have a narrow wheel track to allow it to fit between bollards in shopping precincts, to allow it to sweep on foot paths and generally to minimise the disruption of pedestrians. However, because of the requirement for the narrow wheel track, and because of the weight of the rubbish which can be carried in the rubbish hopper behind the operator which hopper necessarily needs to sit in a upper area of the machine, the machine tends to be unstable and prone to tipping over. To prevent this tendency, manufacturers have in the past tried to lower the centre of gravity, but in a small compact machine this is not particularly easy, especially if the machine is to carry up to a ton of rubbish. Accordingly, in order to prevent tipping over of a full machine, it has been necessary in the past for manufacturers to have to limit the speed of the machine to approximately 10 miles per hour. However, when the speed of the machine is limited, this means that it takes some considerable time for the machine to travel to and from the job, i.e. from the depot of the local council to a city centre. Furthermore, of course, it also takes the machine some considerable time to return to the depot to tip the contents of the hopper once it is full. Accordingly, small or compact slow sweeping machines are not attractive and there is a requirement for a small fast sweeper, but it has to be safe and stable when it is travelling fast.

Sweeping machine with variable wheel tracking


A power generation control system which includes: a fuel cell (201); a target power provider (101) for the fuel cell (201); a operation status monitoring system (102) for monitoring output power from the fuel cell (201), in which the detected output power includes actual output voltage (AV) of the fuel cell (201); and a controller (214). The controller (214) includes: a target current computing unit (104) which calculates a target current (TI) from the target power (TPW) given by the target power provider (101), based on PW-I characteristic obtained from I-V characteristic of the fuel cell (201); and a command output power computing unit (106) which calculates a command output power (CPW) of the fuel cell (201) based on the target current (TI) and the actual output voltage (AV).

In a fuel cell system of a fuel-cell vehicle, output of a fuel cell thereof is controlled based on instructions from a vehicle control system.
While the fuel cell system is in warm-up right after the start-up thereof, or due to the deterioration of the system with age, the output characteristics of the fuel cell thereof change to have a lower output voltage. In order to obtain the required output power from the fuel cell at the lower output voltage, an operation point (output current and output voltage) of the fuel cell is shifted to have the output current increased to thereby compensate for shortage of the output power. However, under heavy load conditions at a relatively high output current, the output voltage sharply drops with increasing output current, which further decreases the output power. The system controls to have the output current further increased in order to gain the output power. This brings about a further drop in the output voltage, and consequently in this vicious circle, the required output power cannot be obtained.
Japanese Patent Application Laid-open No. 2002-231295 discloses a power control system in which an output characteristic of the fuel cell is corrected based on actual output current and voltage thereof, and an operation point is adjusted based on the corrected output characteristic.

Power generation control system for fuel cell


Single-control mixer cartridge for hot and cold water, comprising a body which is associated with a bottom for containing a fixed plate and a movable plate provided with a plate cover which is coupled to an actuation lever pivoted on a rotating coupling; characterized in that the bottom is provided with elements for the stable engagement of a supplemental bottom.

The invention relates to a single-control mixer cartridge for hot and cold water.
As known, devices known as mixer cartridges are widely used in the field of faucets; these cartridges are inserted in the faucets and allow, by acting on a single actuation lever, to vary both the flow-rate delivered by the faucet from zero to a maximum value and the temperature of the delivered water by appropriately mixing the hot water and the cold water that arrive at said faucet.
These devices comprise a bottom provided with two inlet openings for the separate inflow of hot and cold water and with an outlet opening for hot, cold or mixed water, and a body which is associated with said bottom so as to define a portion of space suitable to contain a fixed plate, made of ceramic material and provided with holes corresponding to the openings of the bottom, and a movable plate, also made of ceramic material, which comprises a mixing chamber.
Said movable plate is coupled, with a plate covering element interposed or not, to the above mentioned actuation lever, which is pivoted on a rotating coupling inside said body; in this manner it is possible to make the movable plate assume different positions with respect to the fixed plate, thus obtaining different flow-rates and temperatures of the water delivered by the faucet, according to methods which are too well-known to delve into them.
Known cartridges have a bottom which, by virtue of the shape and arrangement of the openings, is excellently suited for inserting the cartridge in very simple faucets, such as ordinary flush-mount faucets for bathtubs and showers, whereas it is troublesome to insert said cartridge in different faucets, such as for example faucets for washbowls or bidets or for bathtub fittings.
So-called adapter devices have thus been proposed; they are inserted between the cartridge and the base of the cartridge accommodation cavity formed in the faucet; however, these adapter devices are not capable of meeting all the requirements of the various kinds of faucet, and most of all they create maintenance problems since, as they usually remain stuck in said cavity due to the hardening of the gaskets or to lime concretions, they cannot be removed and thus cleaned or replaced when necessary.
There are also cartridges in which the bottom is shaped so that it adapts in optimum conditions to individual types of faucet which are different from flush-mount ones for bathtubs and showers; however, obviously they do not allow interchangeability, since they are targeted for a single type of faucet, with all the consequent and well-known disadvantages.
It should also be noted that known cartridges, and particularly those meant to be inserted in small faucets, often have an inadequate performance as regards delivered water flow-rate and functionality, considered as ease in adjusting the temperature of the water and as ease in sliding during actuation.


An example method for transmitting a random access preamble comprises selecting (502) a random access preamble configuration from a plurality of predetermined random access preamble configurations. The method further includes determining (504) a time interval in which to transmit the random access preamble. The method further comprises transmitting (506) the random access preamble according to the selected random access preamble configuration. Each of the plurality of random access preamble configurations comprises a combination of (a) a single root sequence from a predetermined set of one or more root sequences, (b) a single cyclic shift of a predetermined plurality of cyclic shifts for the root sequence, and (c) a single starting position of two or more predetermined starting positions within time intervals allocated for random access preamble transmission.

The random access (RA) procedure is a key function in cellular communication systems. In the Long-Term Evolution (LTE) wireless communications system standardized by members of the 3rd-Generation Partnership Project (3GPP), a wireless device ("user equipment," or UE) that would like to access the network initiates the random access procedure by transmitting a preamble (Msg1) in the uplink, on the Physical Random Access Channel (PRACH). A base station, access node, or other transmission and receiving point (RTP) receives and detects the preamble and responds in the downlink by transmitting a random access response (RAR, or Msg2). The RAR carries an uplink scheduling grant for the wireless device, with which the wireless device continues the procedure by transmitting a subsequent message in the uplink (Msg3), for terminal identification.
A similar procedure is envisioned for the 5th-generation (5G) wireless network design that is currently under development, in which the radio access network (RAN) may be referred to, for example, as New Radio Access Technology, or simply "NR". FIG. 1 illustrates an example of the basic steps in the initial access procedure for NR, which includes a random access procedure.
As seen in FIG. 1, before transmission of the PRACH preamble, the UE receives one or several Synchronization Signals (SS), which may be referred to as or include, for example, a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), an NR-PSS, and/or a NR-SSS. The UE further receives various configuration parameters on one or more broadcast channels, which may be referred to as or include, for example, a Physical Broadcast Channel (PBCH) and/or NR-PBCH, possibly complemented with configuration parameters received on yet another channel.
A PRACH resource that is common for several SSs (NR-PSS and NR-SSS) has been defined, as described in the 3GPP document R1-1609670, "NR random access procedure," 3GPP TSG-RAN WG1 #86bis, Lisbon, Portugal, Sep. 10-14, 2016. FIG. 2 illustrates the relationship between the PRACH resource timing and SSs and/or the Master Information Blocks (MIBs). The timing from the SS to the PRACH resource (e.g., from a known reference point in the SS to the beginning of the time interval allocated to the PRACH resource) can be indicated in the MIB. Alternatively, this timing is conceivably in the SS itself or another related field, if another system information format should be agreed upon. Different SSs can then be used for different timings, such that the detected sequence within an SS gives the PRACH resource. This PRACH configuration might be specified as a timing relative to SS and PBCH, and can be given as a combination of the payload in the MIB and other broadcasted system information. As seen in FIG. 2, the proposed approach allows for dynamic timing between the SSs and time intervals allocated for the PRACH resource, i.e., the time intervals allocated for transmission of random access preambles. This flexible timing indication of the PRACH resource has lower resource overhead compared to using a fixed timing.
A PRACH preamble design is described in the 3GPP document R1-1609671, "NR PRACH preamble design," 3GPP TSG-RAN WG1 #86bis, Lisbon, Portugal, Sep. 10-14, 2016. This design is illustrated in FIG. 3, where the PRACH is shown along with a Physical Uplink Shared Channel (PUSCH). This PRACH format is based on repeating the same PRACH sequence, i.e., the same PRACH Orthogonal Frequency Division Multiplexing (OFDM) symbol, several times, without a cyclic prefix between the repetitions. Because the repeated symbols are the same, one PRACH OFDM symbol acts as a cyclic prefix for the next PRACH OFDM symbol.
For NR, an OFDM sub-carrier spacing of 15 kHz or 30 kHz is expected to be typically used, for carrier frequencies below 6 GHz. The small sub-carrier spacing formats can be used in larger cells as compared to larger sub-carrier spacing. The large sub-carrier spacing is suitable for time critical initial access, low latency data channels and high-speed scenarios.
NR is also expected to support PRACH preambles of different lengths. FIG. 4 illustrates six formats (x0 to x5) with different lengths of the PRACH preamble. The different formats can be used for different coverage situations, or for different receiver beamforming sweeps. The length of each format is changed depending on the sub-carrier spacing (SCS)—this rescaling of the PRACH preamble formats with respect to the sub-carrier spacing is also illustrated in FIG. 4. Here, a slot is used as the time unit on the horizontal axis, with 14 PUSCH OFDM symbols in each slot.
Further details of the random access procedure for NR, including further details of the random access preamble configuration, remain to be defined.


A material aerating and mixing machine having a material elevator which elevates, mixes and aerates the material to be processed. The material from the elevator is discharged onto a pair of conveyors, a cross conveyor that can be side shifted for windrow turning, and a discharge conveyor that is pivotally mounted for swingable movement in a horizontal plane into a different positions, one position being in line with the cross conveyor for truck loading, another at an angle for stack turning, and a third position where the conveyor is folded for windrow turning or transport. Each of the conveyors is independently powered depending upon the mode in which the machine is operated.

Because of increasing environmental concerns, the disposal and recycling of waste products has created a demand for more efficient ways of treating wastes for conversion into recycled products that have some commercial value. Therefore, composting is being used with increased frequency to convert waste of all types to valuable soil conditioners. Also, soil that has been contaminated by toxic substances must be removed, cleaned of the toxic material and replaced free of the contaminants. Machines are known and available for the bioremediation of soil and for windrowing disposed waste material into rows or stacks so as to allow the naturally occurring bacterial action to biologically digest the organic materials and convert the waste into a useful product. Since these are aerobic processes, the composted material or soil must be processed in order to introduce and trap oxygen in the material to provide for the proper bioremediation. The composted material or soil must be regularly and thoroughly mixed and aerated to allow the natural biological process to work. This bioremediation process will remove the toxic substances from the soil so that the soil can be replaced free of the contaminants. The process will also convert otherwise waste material into a stable and relatively odorless material which can be used as a soil conditioner.
A variety of machines are known and available for aerating and mixing soil or compost material that is either stored in stacks or windrows. Examples of such machines are shown in U.S. Pat. No. 4,932,196 entitled "Compost Windrow Turner" and U.S. Pat. No. 4,976,095 also entitled "Compost Windrow Turner". Machines shown in these two patents are excellent machines for processing contaminated soil or waste material stored in windrows by elevating and completely agitating and inverting the material and returning it to windrows. Other known machines utilize drums or high speed flails or knives that thrash through the stored material to pulverize it. Generally, the typical machine is designed to aerate either windrowed material or stacked material, but not both. Processors of contaminated soil or waste material will commonly use a windrowing machine or a stacking machine, but not both, because of the expense involved. There are situations, however, where a single user may wish to windrow some of the soil or waste material and stack other of the material. In such instances, there is a need for a single machine that can both aerate material in a windrow configuration or aerate material that is in a stacked configuration. It is also highly desirable that such a machine have the capability of loading the material into a truck or other carrier for transport to another site. Also, machines of this type must frequently be moved from one site to another, and it is desirable that such machines be compact for ease of transport with a minimum amount of loading and set-up time.


A global navigation satellite system (GNSS) receiver using phase lock loops for strong GNSS signals and automatic frequency control (AFC) loops for weak GNSS signals on a satellite-by-satellite basis. The phase lock loops or the AFC loops associated with particular GNSS satellites generate frequency feedback adjustments for tracking the carrier frequencies of the incoming GNSS signals in order to determine pseudoranges for calculating a location fix. The transition from an AFC loop to a phase lock loop is controlled for each GNSS signal depending on location quality parameters including a history of previous loop transitions, knowledge of whether a transition is in-progress, and a conditional PDOP. The conditional PDOP is the calculated PDOP where the pseudorange from the particular GNSS signal is removed from the computation of the location fix.

1. Field of the Invention
The invention relates generally to global navigation satellite system (GNSS) receivers and more particularly to GNSS receivers and methods for tracking weak and strong GPS signals by switching between an AFC loop and a phase lock loop.
2. Description of the Background Art
Global navigation satellite system (GNSS) receivers operate by adjusting the phase of a local replica code to the phase of a pseudorandom (PRN) code carried on an incoming GNSS signal. A global positioning system (GPS) is an example of a GNSS receiver.
The local code phase in a GNSS receiver is converted to a range between the local antenna location and the location-in-space of the GNSS satellite transmitting the GNSS signal carrying that particular code. The range is termed a "pseudorange" because the range includes local receiver clock error. In the simplest case, four pseudoranges are needed for resolving the phase offset error and computing a location fix having time and three dimensions of geographic location. Fewer than four pseudoranges can be used if some other information such as altitude or time is available.
More than four pseudoranges can be used for an over-determined solution in order to improve the accuracy of the location fix. GNSS receivers for survey and other applications that require precise locations use carrier phase and differential pseudorange corrections provided by a reference GNSS receiver.
The GNSS receiver must track the frequency of the carrier of the incoming GNSS signal before measuring the pseudorange. The carrier frequency is tracked by generating a frequency feedback adjustment to adjust the frequency of an internal local oscillator (LO) signal (or combination of LO signals) to match the frequency of the carrier. It is important that the LO signal frequency have as little phase noise as possible because phase noise on the LO signal causes noise on the pseudoranges. Noise on the pseudoranges results in less accurate location fixes.
Existing GNSS receivers use a phase lock loop (PLL) for generating a low noise LO signal. However, phase lock loops can cycle-slip or lose lock unless the GNSS signal is relatively strong. In order to operate with weak GNSS signals, some GNSS receivers use an automatic frequency control (AFC) loop for the LO signal. The LO signal frequency provided with an AFC loop is noisier than with a phase lock loop, and the AFC loop does not output the higher accuracy carrier phase measurements, but the AFC loop operates more reliably at lower GNSS signal strengths.
Phase locking with a phase lock loop may take several seconds in order for the phase lock loop to settle to an equilibrium state. During this time period the pseudorange measurement is not available. When that pseudorange measurement is one of the minimum set that is being used for a location fix (four in the simplest case) then no location fix is available during the time that the phase lock loop is settling.
Even when the location fix is using more than the minimum set of pseudoranges, the location fix is subject to jumps before and after the phase lock loop settles when the GNSS receiver makes the transition to the phase lock loop. These problems may be tolerable when the signal strength does not often change between weak and strong. Unfortunately, there are cases where the GNSS signal strength changes rapidly such as when the GNSS signal is subject to multipath or the GNSS receiver is beneath a tree canopy. When the GNSS receiver is beneath a tree canopy, the loop transition problem may occur each time the GNSS satellite or the GNSS receiver moves just enough to pass by a branch or leaf in the line-of-sight between the satellite and the receiver.

GPS receiver having a phase lock loop hold off


A method and an apparatus are disclosed for monitoring and protecting a program system against buffer overrun attacks. The method includes identification of whether there is an unsafe combination of rights for a loaded memory segment; a check to determine whether an unsafe combination of rights is permissible as an exception, and a defense measure, through deletion of the right if there is an unsafe combination of rights and this combination of rights is not permissible. The method also may include a repair measure which repairs the damage which has been caused by the deletion of the right.

One of the most frequent security gaps is what is known as buffer overrun or buffer overflow. This basically involves damage which is caused by a buffer or a memory area of a program being filled beyond its boundaries. Data are written beyond the end of the buffer. Thus, the data which are relevant to program execution are overwritten. Some of the aforementioned attacks are based on the principle of writing an executable code to the stack, which is then executed and can cause errors which are in some cases serious.
Errors of this type arise predominantly in traditionally compiled programming languages, such as C+ and C++, since these languages do not offer automatic checking of access operations to fields and memory segments for performance reasons. Programming errors can also cause the aforementioned security problems by making inadequate requests for the boundaries of the fields which are written to the stack dynamically. A hacker can exploit this by feeding a hacking code into the local buffer which will be executed at a later time.
In the operating systems which are popular today (Windows 95 and above), each processor has its own logical address space. An area in this address space is taken up by a stack. When a program is started, the operating system usually creates three segments in the virtual memory: the code segment, the data segment (heap segment) and the stack segment. The stack is a buffer store for local variables, transfer parameters for functions and also for return addresses for subprograms. The stack starts at a defined address, principally at the end of the address space, and grows downward and on the basis of the last-in-first-out principle (LIFO buffer). Its size is mainly dependent on the recursion depth of the respective program. Possible instructions for editing the stack are the push and pop instructions for writing data to the stack and reading the data from the stack. In addition, it is possible to address individual stack elements directly.
During a hack, information is deliberately written to the stack beyond its end, so that the return address of a function is overwritten with a fed address. When the function has been executed, the program is therefore no longer able to return to the calling function, but rather jumps to the fed address. If the fed address is a randomly selected address, the program in question is usually merely terminated without causing further damage. If the fed address is a valid address in the program, the program is executed in manipulated fashion and hence incorrectly. Most attacks feed an address which refers to stack addresses onto which the hacking code has previously been loaded and hence can cause massive and extensive damage.
To be able to ensure protection against such attacks, it is known practice in systems from the prior art to use what are known as virus scanners, security updates and firewalls. A virus scanner uses the patterns known to it (code patterns for known viruses) to detect an attack. A drawback of this known solution is that the virus scanner works only when it has a pattern for the respective worm or virus so as to be able to trigger an alarm. That is to say that the patterns need to be constantly updated and their quality is dependent on the update level.
Security updates are normally modified operating system components which are provided by the manufacturer and repair security gaps which have already been detected. A fundamental problem of security updates can be seen in that the system basically has no protection in the time between release by the manufacturer and identification of the security gaps. In addition, another problem is that it is not possible to provide protection for security gaps which are not yet general knowledge, that is to say those which, although already known to a limited group of users, have not yet been listed.
Firewalls are active network communication components. They work in the manner of a barrier which passes on only particular network traffic. One difficulty of programming firewalls is not setting the firewall's barrier too high, so that the computer communication is restricted too much, and similarly not setting the barrier too low, which would result in an increased security gap.
In addition, it is known practice in Windows-based operating systems to resort to the processor technology. In this context, the processor technology from the company AMD provides what is known as the No-execute-Page-Protection processor feature (NX). The processor technology from the company Intel has a similar feature, known as the Execute-Disable-Bit-Feature. The 64-bit architectures in Windows support the aforementioned hardware, which provides an instruction rejection function (Data Execution Prevention, DEP). Stack and heap are marked as data by the Windows operating system. If an application now attempts to call a memory page marked as NX, the processor triggers an "exception", which results in the triggering process being terminated or interrupted.
A fundamental drawback of this solution can be seen in that earlier applications are no longer able to work following installation of the Microsoft Service Pack. Earlier programs therefore may need to be completely revived, which entails a high cost risk. Furthermore, it is disadvantageously necessary to use a particular processor technology. Other computer architectures, particularly the 32-bit architecture, are therefore excluded from protection. A further drawback of this approach can be seen in that there is no protection for attacks which relate to memory segments other than the stack or the heap.

Method and apparatus for protecting against buffer overrun attacks


An imaging system comprises a device to excite mechanical waves in elastic tissue, a device for measuring the resulting tissue motion at a plurality of locations interior to the tissue at a number of time instances, a computing device to calculate the mechanical properties of tissue from the measurements, and a display to show the properties according to their location. A parameter identification method for calculating the mechanical properties is based on fitting a lumped dynamic parametric model of the tissue dynamics to their measurements. Alternatively, the mechanical properties are calculated from transfer functions computed from measurements at adjacent locations in the tissue. The excitation can be produced by mechanical vibrators, medical needles or structures supporting the patient. The measurements may be performed by a conventional ultrasound imaging system and the resulting properties displayed as semi-transparent overlays on the ultrasound images.

1. Field of the Invention
This invention relates to diagnostic imaging in general, and to measurement of the mechanical properties of tissue in particular.
2. Description of the Related Art
The basis of medical imaging is the measurement of a property of tissue that varies with tissue composition. Medical images are formed by displaying intensities as a function of these properties measured at multiple locations in the body. From such images, a depiction of anatomy or pathology is gained. Each different imaging modality in common use, such as X-ray, computed tomography, ultrasound and magnetic resonance imaging, measures a different property of tissue.
Mechanical properties of tissue are important indicators of disease potential. Indeed, palpation techniques are commonly used by medical doctors to determine the potential for disease—for example, stiffer tissue regions that can be felt as harder objects can indicate the presence of breast or liver malignancies. There are a number of in-vivo techniques for measuring mechanical properties of tissue.
Static Elastography is a new medical imaging modality that aims to depict elasticity, a mechanical property of tissue. Elasticity is also referred to as stiffness, or the inverse compliance. The variation of elasticity among tissue types and pathology is well known. A number of journal articles describing the clinical applications of elastography are listed by Hall et al. in U.S. Pat. No. 6,508,768. In fact, elastography can be considered as an extension of the traditional diagnostic technique of palpation—the pressing of tissue to feel for differences in elasticity.
The history and development of elastography is given in the following reviews:
J. Ophir, S. K. Alam, B. Garra, F. Kallel, E. Konofagou, T. Krouskop and T. Varghese, "Elastography: ultrasonic estimation and imaging of the elastic properties of tissue", J. Eng. Med., 213:203-233, 1999.
J. Ophir, I. Cespedes, H. Ponnekanti, and Y. Yazdi, "Elastography: ultrasonic imaging of tissue strain and elastic modulus in vivo", Eur. J. Ultrasound, 3:49-70, 1996.
L. Gao, K. J. Parker, R. M. Lemer and S. F. Levinson, "Imaging of the elastic properties of tissue—a review", Ultrason. Med. Biol., 22(8):959-977, 1996.
Depending on the technique of generating the measured tissue displacement, static elastography methods can be classified as employing global deformation or local deformation.
Measurement of applied global deformation. In static elastography, two images are taken of a region of tissue. One image is taken during compression of the tissue with a nominal static external force. The second image is taken during compression with a higher static external force. The difference between the images is used to calculate relative elasticity. The external force refers to axial pressure applied typically to the surface of the skin above a region of interest. The basic principle is that stiff tissues will compress less than compliant tissues. Dividing each image into small regions and comparing the movement of these regions between the two images provides a quantitative measurement of the local strain. Provided the stress induced from the external force is uniform throughout the tissue, then local elasticity estimates can be made. The underlying assumption is that the strain is linearly related to the stress and that this relationship is described mathematically by a linear scale factor called the Young's modulus, or simply elasticity. Ultrasound is a common imaging modality for this method because it is ubiquitous, non-invasive, safe, inexpensive and portable. Patents of this approach include those by Ophir et al., in U.S. Pat. Nos. 5,107,837, 5,178,147, 5,293,870, 5,474,070, Konofagou et al in U.S. Pat. No. 6,270,459, Alam et al. in U.S. Pat. No. 6,514,204, Steinberg et al. in U.S. Pat. No. 5,839,441, Hall et al. in U.S. Pat. No. 6,508,768, VonBehren et al. in U.S. Pat. No. 6,558,324 and Cohen-Bacrie et al. in U.S. Pat. No. 6,176,827. The differences among these patents are mainly in the construction of the apparatus, the methods to compute strain from the ultrasound data and the display of the results.
Measurement of local deformation in response to focused ultrasound excitation. The second category of static elastography describes methods that excite only a small volume of tissue interior to the body using high intensity focused ultrasonic waves. In Nightingale et al. in U.S. Pat. No. 6,371,912 the high intensity ultrasound produces an acoustic radiation force and is measured with a second set of low-intensity ultrasound images. The high intensity pushing pulses are interleaved with the low intensity imaging pulses to provide more rapid measurements. The relative local displacement is measured at different locations and displayed. The displacements are related to the local elasticity. Tissue dynamics are not captured in the process.
The major disadvantage of all static elastography methods is that they measure only static properties of tissue. In addition, because static elastography uses information at a single frequency (zero Hz or dc), the method is sensitive to noise and measurement bias.
In what we will call dynamic elastography, a force is applied to tissue and the resulting tissue motion is measured, i.e., multiple tissue displacement or velocity measurements are made over a period of time. These measurements can be displayed directly (e.g., measured magnitude of tissue velocity generated by a vibration source) or following some excitation-dependent signal processing (e.g., the quality factor of the tissue velocity frequency response to a vibration source acting at different frequencies).
There are many methods proposed for dynamic elastography. We will classify these broadly into the following four categories, based on whether tissue excitation and measurement is local, and whether there is an underlying tissue model whose parameters are being identified.
We will start by discussing three approaches that do not rely upon fitting the data to a parameterized tissue model.
Velocity response to an external vibration source. The first category of dynamic elastography describes methods that apply mechanical waves globally to a region of tissue using an external vibration source and then measure the resulting tissue motions. The tissue response is usually measured by ultrasound as described in Parker et al. in U.S. Pat. Nos. 5,086,775, 5,099,848, and Lin in U.S. Pat. Nos. 5,919,139, and 6,068,597. Ultrasound is normally used here because Doppler imaging is widely available on commercial ultrasound machines. The Doppler signals measure local velocity and the absence of velocity can indicate the presence of stiff inclusions such as tumors. As an alternative, magnetic resonance imaging offers improvements in image quality, at the expense of speed and cost. See for example, U.S. Pat. No. 6,486,669 described later.
In the methods disclosed in U.S. Pat. Nos. 5,086,775, 5,099,848, 5,919,139, and 6,068,597, the tissue is excited with a vibrator at audio frequencies and the tissue response is measured by power Doppler measurements. In U.S. Pat. Nos. 5,086,775 and 5,099,848, a mechanical exciter sweeps through a range of audio frequencies until a resonant frequency is detected. In U.S. Pat. No. 5,086,775 Doppler shifted signals are analyzed to find the vibration amplitude of a given region of interest. In U.S. Pat. No. 5,099,848, Doppler shifted signals are analyzed to find the vibration amplitude, the discrete eigenmodes, and eigenfrequency of the tissue. These measurements are then converted into other properties such as shear velocity and Q parameter—the quality factor—and displayed. In U.S. Pat. No. 5,919,139, the Doppler shifted signals are analyzed to find the tissue vibration amplitude, the frequency, and the variance. Various combinations of these properties are displayed. In U.S. Pat. No. 6,068,597, the tissue is vibrated with a wide range of frequencies to obtain the full frequency spectrum of the tissue at different locations. Various measurements of the shape of the spectrum around the resonance peak are then displayed.
In all four of these dynamic imaging patents, measurements are made of the velocity and resonance behavior of the tissue, but they are not based on modelling the underlying properties of the tissue, such as the elasticity, viscosity and density that produces the resonance behavior. Moreover, the measurements must be made with an excitation of only one frequency at a time, making the acquisition of data slow.
Tissue response from localized displacements. Sarvazyan in U.S. Pat. No. 5,606,971 uses high-intensity focused ultrasonic waves that are amplitude modulated to generate shear waves at a single location in the tissue. To obtain an image, localized excitations and measurements are repeated at different locations. The shear waves are detected by measuring their amplitude and phase on the surface of the tissue. At least one propagation parameter of the shear waves in the tissue is determined from the phase and amplitude measurements. The parameter can be one of the following group of parameters: shear wave velocity, shear wave attenuation coefficient, amplitude and velocity of shear displacement of tissue particles in the propagating shear wave, spatial an temporal dependencies of these amplitude and velocity of shear displacement of tissue particles. From these calculations, at least one mechanical parameter of tissue is derived, such as shear elasticity modulus, Young's modulus, dynamic shear viscosity, and mechanical impedance. The way the data is analyzed is local in the sense that the calculation of a tissue parameter at a single location is done without considering the effect of the properties of the neighboring tissue regions. This type of analysis is possible because the spatial decay of shear waves is rapid, so neighboring effects are neglected. The requirement that localized shear waves be used constitutes a significant drawback. Only one small region can be excited at a time and the excitation-measurement process must be repeated for multiple regions. This reduces the speed of forming a complete image. And again, the use of high intensity focused ultrasound poses a possible hazard to the patient.
Acoustic emissions from localized displacements. These dynamic elastography methods directly measure the acoustic emissions produced by tissue vibrating as a result of a localized oscillating radiation force. For a constant frequency radiation force, tissues with different viscoelastic properties will produce different emissions. The main idea is to create an oscillating point force in the tissue and measure the emission with a hydrophone. By raster scanning the point source across a region of interest, an image is formed from the magnitude or phase of the measured emissions. The oscillating point force is produced by the intersection of two focused continuous wave ultrasound beams at different frequencies. The interference of the beams at the focal point produces sinusoidal modulation of the ultrasound energy, effectively vibrating the tissue at that point. The use of such systems is called vibro-acoustography. See Greenleaf et al. in U.S. Pat. Nos. 5,903,516 and 5,991,239. The drawbacks of this approach include the need for specialized equipment for both producing the oscillating point force and measuring the emissions. It also does not measure the underlying properties of the tissue, only the resonance behavior. Moreover, it requires raster scanning of a region of interest, instead of allowing simultaneous measurements. This reduces the speed of forming a complete image.
Both localized methods—tissue response and acoustic emissions—produce images of one or more aspects of the tissue response to the dynamic excitations, but do not identify a specific model of the tissue dynamics. Alternatively, the tissue dynamics can be modelled using a parametric model, and the model parameters can be obtained from the measured responses to tissue excitation. The dynamic response of human tissue depends on both the amplitude and the frequency of the excitation (Y. C. Fung, "Biomechanics: Mechanical Properties of Living Tissues", Springer, 1993). Nevertheless, if the amplitude of excitation is small, and frequencies are low, then a linear viscoelastic model can used as a reasonable approximation of the tissue dynamics. We now discuss two approaches that attempt to fit the data to a linear parameteric tissue model.
Parameter identification based on the wave equation and sinusoidal excitation. Sinkus et al. in U.S. Pat. No. 6,486,669 use a mechanical external excitation and magnetic resonance imaging to extract tissue properties from a linear viscoelastic model. This is therefore categorized as having global excitation with model parameter identification. A method is disclosed for vibrating the tissue to create longitudinal mechanical waves with periodic signals, preferably sinusoids, and to obtain the phase and amplitude of the single tone sinusoidal vibrations. To obtain both phase and amplitude, the images and the excitation must be carefully synchronized. From these measurements, they solve the wave equation for the viscoelastic model and calculate the model parameters of elasticity, Poison's ratio, tissue density and attenuation. In particular, the time independent solution of the partial differential wave equations is used. With a time independent approach, the tissue must be excited with a periodic signal, such as one or more toned sinusoids, and an equilibrium must be reached to eliminate the transient responses. Thus, this method is restricted to using excitations with periodic amplitudes to be able to reach equilibrium, and where the ratios of the frequencies is an integer.
The requirement that the excitation consist of carefully controlled frequencies and phases in synchronization with magnetic resonance imaging means that a very complicated system is needed compared to other techniques. Another limitation is the need to reach an equilibrium state before measurements can begin. Since tissue relaxation in response to an excitation may take seconds, the reported times required to obtain an image of parameters is of the order of 30 minutes (R. Sinkus, J. Lorenzen, D. Schrader, M. Lorenzen, M. Dargatz, and D. Holz, "High-resolution tensor MR elastography for breast tumour detection", Phys. Med. Biol. 45, 2000).
Measurement and parameter fit to localized time response to focused ultrasound excitation. In a paper by F. Viola and W. Walker, "Imaging viscoelastic properties of the vitreous", IEEE Ultrasonics Symposium, 2001, focused ultrasound is used to generate a step force in a localized region of tissue. This tissue region is displaced as a result, and its displacement as a function of time is used to identify the relative stiffness and relative viscosity with which this region is connected to neighboring tissue. This is therefore categorized as having local excitation with model parameter identification. While this method does measure dynamic properties of tissue (relative viscosity), it suffers from a number of drawbacks. First, while focused ultrasound can produce a step force in a small isolated region, this process must be repeated many times at many locations to form a complete image. The speed of the repeated measurements is limited by the need for the tissue to relax from the step force. Viola et al. do not describe a method to speed up the imaging of a larger region and such method is not obvious. Second, the identification technique Viola et al. use to compute relative stiffness and viscosity relies upon the step response of tissue. In essence, a fit to an exponentially decaying tissue region displacement must be obtained. It is well known to experts in parameter identification (see for example L. Ljung, "System Identification, Theory For The User", Prentice Hall, 1999) that such an approach can fail in the presence of noise. Third, in order to obtain dynamic tissue parameters, Viola et al. fit the actual tissue region response to a model using nonlinear optimization techniques. Many iterations may be required for such an approach to produce a set of parameters. Furthermore, there may be local minima.
So in summary, the static elastography methods (both local and global excitation methods) are incapable of measuring the dynamic properties of tissue. The dynamic elastography methods with local excitation have shown an ability to measure some dynamic properties, but the local nature of excitation makes the imaging procedure slow. The current dynamic methods with global excitation are also slow because of the need to either synchronize with the imaging device after equilibrium, or sweep through a range of excitation frequencies. Those methods that excite only a single frequency can only characterize a subset of the dynamic properties, compared to methods that excite a range of frequencies. Moreover, no dynamic elastography method (including the dynamic methods with either local or global excitations) has so far proposed a method of excitation combining multiple frequency components together, so that robust system identification techniques can be employed to identify the tissue properties.

Method for imaging the mechanical properties of tissue


To stabilize the arc bright point position of a discharge lamp and suppress deformation of an electrode when an ultrahigh-pressure discharge lamp is operated with extremely low electric power, the lamp is operated by supplying power from a power supply device having a step-down chopper circuit and a full bridge circuit, a rectangular wave alternating current being supplied when it is operated with rated power or dimmed power (about 60 to 80% of rated power), a DC current being supplied during standby power operation of at most 0.5×P (W) with respect to the maximum operating power P (W). Moreover, the high-pressure discharge lamp light source device may be mounted on a projector for projecting images and the mode being changed to standby power operation when there is no change in an image signal, for example, for a prescribed period of time.

1. Field of Invention
The present invention relates to a high-pressure discharge lamp light source device and a projector in which the high-pressure discharge lamp light source device is mounted. Particularly, the present invention relates to an alternating current type high-pressure discharge lamp having a light emitting tube in which at least 0.2 mg/mm3 of mercury is sealed, and therefore, the mercury vapor pressure is high (e.g., 110 atm or higher), the high-pressure discharge lamp being suitably used as a projection light source for projection type projector devices, rear projection televisions and the like, a high-pressure discharge lamp light source device comprised of the high-pressure discharge lamp and its light source device, and a projector on which the high-pressure discharge lamp light source device is mounted.
2. Description of Related Art
It is required for a projection type projector device to illuminate images on a rectangular screen uniformly with sufficient color rendition. Accordingly, a metal halide lamp in which mercury or a metal halide is sealed is used as a light source. In addition, the recent trend has been to reduce the size more and more to the level of a point light source, and one having an extremely small distance between the electrodes has practically been used.
Under these circumstances, a high-pressure discharge lamp having an extremely high mercury vapor pressure (e.g., 20 MPa (about 190 atm) or higher) has recently been used in place of a metal halide lamp. The purpose of this lamp is to narrow down the width of the arc by increasing the mercury vapor pressure and further increase the light output. In the above-mentioned ultrahigh-pressure discharge lamp, a pair of electrodes is disposed inside a light emitting tube made of quartz glass in a manner of facing each other with a distance of at most 2 mm, for example, and mercury of not less than 0.20 mg/mm3, a rare gas, and a halogen in the range of 10−6 μmol/mm3 to 102 μmol/mm3 are sealed inside the light emitting tube (See, e.g., Published Unexamined Japanese Patent Application No. H2-148561 and corresponding U.S. Pat. No. 5,109,181).
This type of discharge lamp and its light source device are disclosed in Published Unexamined Japanese Patent Application No. 2001-312997 and corresponding U.S. Pat. No. 6,545,430, for example.
In the high-pressure discharge lamp disclosed in Published Unexamined Japanese Patent Application No. 2001-312997 and corresponding U.S. Pat. No. 6,545,430, the mercury vapor pressure inside the tube is in the range from 15 MPa to 35 MPa during steady lighting state; halogen in the range of 10−6 μmol/mm3 to 102 μmol/mm3 is sealed inside the light emitting tube; a pair of electrodes is provided inside the light emitting tube; and a protrusion is provided in the vicinity of the center of the tip end of the electrode so as to suppress the occurrence of the so-called arc jump phenomenon, the arc jump phenomenon being a phenomenon in which the position of the discharge arc generated between the electrodes becomes unstable and moves around between the center of the tip end of the electrode and the periphery thereof. An alternating voltage is applied between the pair of the electrodes for operation using a power source device comprised of a DC/DC converter, a DC/AC inverter and a high-voltage generator.
On the other hand, as the size of the projector is so reduced recently, so that it can be used in ordinary homes, there is a need for considering a screen that is not too bright in synch with the brightness of the use environment and the type of images to be projected. In response to such a need, a projector having a function referred to as the dimming function has been designed (See, e.g., Published Unexamined Japanese Patent Application No. 2000-131668). Here, the dimming function refers to a function for adjusting the brightness of a lamp and reducing the consumed electric power by operating a high-pressure discharge lamp with electric power lower than the rated electric power. As used herein, the term "dimmed power operation" refers to operation with electric power lower than the rated electric power.
The present high-pressure discharge lamp light source device is usually provided with both the "rated power operation" and the "dimmed power operation." As used herein, the operation with the "rated power operation" and the "dimmed power operation" is defined as the steady operation. Besides, the "dimmed power operation" is generally operated with electric power that is 60 to 80% of the "rated power operation."
FIG. 18 shows one example of the electric current waveform when a high-pressure discharge lamp is operated using a light source device having the dimming function. As shown in the figure, the electric power is reduced to about 60 to 80% of the rated power operation for operating a lamp when the dimmed power operation command signal is turned on during the rated power operation.
Furthermore, a projector having a function referred to as the AV mute has recently been designed, for example, that stops projecting images temporarily when the projection of images on a screen is not required.
Such a function can be achieved by mechanically shutting down the discharge lamp considering the fact that relighting is not available immediately after turning off the light of the discharge lamp because the internal pressure is high, by shutting down light to be projected onto a screen by adjusting the voltage to be applied to a liquid crystal panel, or the like. As used herein, the term "standby power operation" refers to the operation of a lamp in a state where images are not projected on a screen deliberately.
In the standby power operation, it is desirable that the power is as low as possible. This is because the operation with power as low as possible allows markedly decreasing heat generated from the lamp and stopping or significantly decreasing the drive of a cooling fan, which is the major cause of noise generated by a projector, thereby making the noise generated by the projector as small as possible.
Moreover, since the thermal load of the lamp can be reduced by operating the lamp with low electric power, the lifespan of the lamp can be prolonged by combining the case in which projection is required with the case in which projection is not required. As used herein, the term "thermal load" refers to the thermal load on the light emitting tube and electrodes, which can be reduced with smaller input power.
Besides, one of the properties of a projector is the contrast ratio. The contrast ratio refers to the ratio between the brightness on a white screen for projection (bright state) and the brightness on a black screen (dark state). When the contrast ratio is high, an image having a clear distinction between brightness and darkness can be projected and, therefore, is an important property of a projector together with the brightness.
In order to increase the contrast ratio, a technology for creating the black state using the above-mentioned shutting down function (iris adjusting function) has recently been adopted.
There is a need for a high-pressure discharge lamp that enables brightness of a prescribed level or higher during the rated power time to be achieved and allows not only for the dimmed power operation as described above, but also the standby power operation, which is achieved by lowering the dimming power as much as possible.
As described above, there is a need for a high-pressure discharge lamp that allows for the standby power operation, which is achieved by lowering the electric power as much as possible. However, the following problems may occur when the power is significantly decreased in a state where rectangular wave alternating current is being supplied.
In this type of high-pressure discharge lamps, as described in Published Unexamined Japanese Patent Application No. 2006-332015, for example, a protrusion is formed on the tip end of the electrode during operation and a stable arc discharge is formed centering on the protrusion. It is described in Japanese Patent Application No. 2006-332015 that the stable operation is possible by maintaining the protrusion, which is the starting point of an arc, wherein the stability can be achieved by changing the frequency or the number of waves of a stationary frequency and a low frequency, which is intermittently (periodically) inserted, depending on lamp voltage or lamp operation power. However, the starting point of the arc became unstable and the so-called flicker phenomenon frequently occurred when a high-pressure discharge lamp (e.g., a lamp with the rated power of 180 W) was operated with 90 W using the abovementioned technology, which problem occurred in any combination of frequencies. Particularly, this problem markedly occurred with 70 W relative to the rated power of 180 W.
In order to solve the abovementioned problem, the object of the present invention is to provide a high-pressure discharge lamp light source device that can positionally stabilize the starting point of an arc in a discharge lamp, thereby preventing the occurrence of the so-called flickers, even when the lamp operation power is extremely low, i.e., the operating power is at most 0.5×P (W) with respect to the maximum operating power P (W) in the steady operation state and that does not influence the lighting operation in the screen projection mode by suppressing the deformation of the electrode as well as a projector on which the high-pressure discharge lamp light source device is mounted.

High-pressure discharge lamp light source device having a power supply device with a switching state for switching from a direct current drive in a standby state to an alternating current drive in an operating state and projector


A hybrid resource manager is provided for use in a computing environment. The hybrid resource manager serves as the single resource manager that cooperates with an operating system to manage each of the individual device drivers associated with the various functions of a multifunction hardware device. In one example the hybrid resource manager implements a consistent management and policy framework to prevent conflicts from arising when multiple functions are simultaneously requested by various applications.

Operating systems employ resource management schemes to limit the interference between applications, implement policies that prioritize and otherwise control resource allocations, and generally manage the overall behavior of a system that is running many independent software applications. Usually, a resource manager is provided for each class of devices. Examples of such device classes include, peripheral devices such as keyboards, printers, facsimile machines, scanners, CD and DVD players, network interfaces, smartcard readers, biometric scanners, and memory storage devices (e.g., flash memory). Each of the different classes of devices typically have their own resource manager. Because particular devices within a given class are generally slightly different from one another, an additional software component known as the device driver is commonly provided with each particular hardware device. The device driver acts as a translation layer between the resource manager and the particular hardware device.
Device drivers are commonly used in computer systems as the lowest level software component to communicate with hardware devices. Typically, these device drivers are associated with the devices they control in a one-to-one relationship. For example, a serial port driver is associated with the data/fax serial modem of the computer, an Integrated Switched Digital Network (ISDN) driver is associated with an ISDN interface device, and a network driver provides the interface to a Wide Area Network (WAN) data interface device. In such an arrangement, each dedicated driver manages the start-up, shutdown, maintenance, and functional operations for the hardware device.
Due to advances in technology, it has become possible to integrate multiple hardware devices into a single multifunction device. For example, a single hardware device may be capable of performing one or all of the functions of a data/fax modem, ISDN, and WAN interface. Another example may be a keyboard that has an integrated smart carder reader and a biometric scanner. Such multifunction devices have several advantages over multiple single function devices, including reduced cost, smaller size, reduced load on the host system and easier installation. However, to remain compatible with legacy applications, these multifunction devices still require dedicated drivers for each function, e.g., keyboard, smart card reader, and biometric scanner, etc. Since each device driver functions independently, situations can arise in which multiple device drivers send commands to the single hardware device. Thus, there exists the possibility that the commands sent by one driver may conflict with the commands sent by another driver, resulting in a system malfunction. For example, one driver may send a command to shutdown the hardware device while other independent drivers are using the device. Another example is where one driver attempts to run a diagnostic test that requires exclusive access to the multifunction device to ensure valid results, and another driver attempts to access the multifunction device during this diagnostic test. There are numerous conflicts that can occur with multiple device drivers accessing a single multifunction hardware device.
FIG. 1 illustrates a computer system 10 having a plurality of device drivers, i.e., device driver A 2, device driver B 4, and device driver C 6 being connected to a multifunction device 8. In operation, an application residing on computer system 10 may request a first function to be carried out by multifunction device 8. When a function is requested, computer system 10 directs the driver corresponding to the requested function to send commands to multifunction device 8 in order for it to perform the requested function. For example, if function A is requested, computer system 10 directs device driver A 2 to send commands to multifunction device is 8 to perform function A. However, as described above, some device drivers may issue conflicting commands to the multifunction device. Conflicting commands being sent from different drivers may result from numerous scenarios in a system with a multifunction device. For example, while multifunction device 8 is being directed to perform function A by device driver A 2, computer system 10 may direct device driver B 4 to issue commands to multifunction device 8 to perform function B. Part of the commands issued by device driver B 4 may be device initialization commands which conflict with the commands being issued by device driver A 2. In such cases, the multifunction device may not perform some or all of the requested functions because of the conflict.
In addition to conflicts, another problem that arises when multiple drivers are used with a multifunction device concerns security. For example, it is often necessary to ensure that at any given time, an application is using only one specific function of the multifunction device 8 and that all others are locked down.
One possible solution to this problem is to combine the device drivers into a single multifunction driver, and thereby prevent conflicting commands using programmatic methods. However, this approach may require that a large portion or all of the software code of the existing drivers be rewritten to be able to work as a single driver. This solution also reduces the modularity of the software. A single combined driver is larger and more complex, and therefore is more difficult to create, test, maintain, and upgrade. Combining multiple drivers into a single multifunction driver can increase the total number of drivers required, when all the different permutations and combinations of drivers and multifunction devices are considered. Thus, it is highly desirable to keep the drivers separate.