An apparatus, method and computer program for correcting a common phase error (CPE) of symbols of a received OFDM signal is described, in which FFT processing may be performed on a time domain OFDM to transform the received signal to a signal in the frequency-domain. Reordered output values resulting from the FFT processing and locations of the reordered output values may be stored. One or more of the stored reordered output values for a current symbol of the OFDM signal may be transferred based on receipt of an address, and each of the transferred reordered output values may be multiplied by a corresponding reordered output value of a previous OFDM signal symbol, so as to determine phase differences between the reordered output values of the current and previous OFDM signal symbols. The CPE of the transformed OFDM signal may be corrected based on the detected phase differences.

1. Field of the Invention
The present invention generally relates to an apparatus, method and computer program for correcting a common phase error (CPE) of symbols of a received orthogonal frequency division multiplexing (OFDM) signal.
2. Description of the Related Art
In general, a digital High Definition Television (HDTV) broadcast system may be divided into two parts, i.e., an image encoder and a modulator. The image encoder may compress about 1 Gbps of digital data, obtained from a high definition image source, for example, into about 15˜18 Mbps of data. The modulator may transmit several Mbps of digital data to a receiving part of the HDTV broadcast system through a substantially narrow channel having about a 6˜8 MHz frequency band.
A modulation technique used in an HDTV broadcast system typically may need high frequency band efficiency in order to transmit several Mbps of digital data through such a limited frequency band to a receiving part of the system. In addition, since an HDTV broadcast system may adopt a simultaneous terrestrial broadcast manner using VHF/UHF channels originally allotted for a conventional analog television broadcast, the HDTV broadcast system may require given characteristics so that the system may be sufficiently robust against channel interference that may be caused by analog television signals.
In an effort to enhance the efficiency of data transmission per bandwidth, and also to reduce and/or possibly prevent interference, orthogonal frequency division multiplexing (OFDM) has been adopted as a next-generation HDTV terrestrial broadcast technique. OFDM is digital modulation in which a column of symbols input in series is transformed into parallel data symbols, and the parallelized symbols are multiplexed into different subcarrier frequencies. In OFDM, multiple carriers which are orthogonal to one another may be used. Two carrier waves ('carriers') may be said to be orthogonal if the dot product of the two carrier waves is equal to zero. The use of orthogonal subcarriers allows the subcarriers' spectra to overlap, thus possibly increasing spectral efficiency. As long as orthogonality is maintained, it may still be possible to recover the individual subcarriers at the receiver with accuracy, despite the overlapping spectrum of the subcarriers.
Since OFDM signals may be generated by multiple carrier frequencies, OFDM signals may be vulnerable to tuner phase noise. Tuner phase noise may affect an OFDM signal in at least two different ways. For example, tuner phase noise may introduce low-frequency phase variations. The result of these variations may be a constant phase rotation for all of the subcarriers in the frequency domain. This phenomenon is referred to as a common phase error (CPE). Second, tuner phase noise may cause inter-carrier interference (ICI), which is determined by high-frequency phase noise variations. The result of the ICI may be signal-to-noise ratio degradation due to interference from the other subcarriers. The occurrence of the two phenomena, i.e., CPE and ICI, may depend on the spectral properties of the phase noise and frequency spacing between adjacent subcarriers of the OFDM signal.
CPE generally may cause HDTV broadcast system performance to deteriorate. However, CPE may be estimated based on the received OFDM signals and then corrected. Conventional CPE correction methods have been suggested by J. H. Scott in the article entitled "The DVB Terrestrial (DVB-T) Specification and Its Implementation to a Practical Modem" (International Broadcasting Convention, 1996) and P. Robertson and S. Kaiser in the article entitled "Analysis of the Effects of the Phase Noise in Orthogonal Frequency Division Multiplexing (OFDM) Systems" (IEEE Int. Conf. On Communication, ICC'95).
FIG. 1 is a block diagram of a prior art OFDM signal receiving apparatus. An OFDM signal; in general, may include a plurality of subcarriers having a given frequency, amplitude, and phase. These subcarriers may be referred to as continual pilots (CPs). For example, a Digital Video Broadcast-Terrestrial (DVB-T) system uses 45 CPs in a 2K mode and uses 177 CPs in a 8K mode. Referring to FIG. 1, in a OFDM signal receiving apparatus 100, an input signal IN may be converted into an intermediate frequency signal by a tuner 102 and a local oscillator 104. The intermediate frequency signal may be converted into a digital signal by an A/D converter 106 and converted into a complex baseband signal by an IQ demodulator 108. The output of the IQ demodulator 108 may be provided to a Fast Fourier Transform (FFT) unit 110 so that a guard interval is removed from each OFDM symbol of the received complex baseband signal (i.e., of the OFDM signal) for carrying out fast Fourier transformation in order to transform time-domain signals into frequency-domain signals.
A first CP extractor 114 may extract first CP signals CP1 of a given symbol of the OFDM signal from an output of the FFT unit 110, and may transmit the CP1 signals to a complex conjugate multiplier 118. The output of the FFT unit 110 may also be transmitted to a second CP extractor 116 via a one-symbol delay unit 112. The second CP extractor 116 may extract second CP signals CP2 from a previous symbol of the OFDM signal passing through the one-symbol delay unit 112, and may transmit the CP2 signals to the complex conjugate multiplier 118. The complex conjugate multiplier 118 may multiply the CP1 and CP2 signals, which may have the same frequencies, thus detecting phase differences between the CP1 and CP2 signals.
An output of the complex conjugate multiplier 118 may be transmitted to an averaging circuit 120. The averaging circuit 120 may average detected phases of all CP signals in a given symbol received from the complex conjugate multiplier 118, in order to remove noise components. The averaging circuit 120 may output a complex signal to a phase extractor 122. The phase extractor 122 may detect the phase of the complex signal. Phase detection outputs of the phase extractor 122 may be accumulated in an accumulator 124. The accumulator 124 may provide an accumulated output to a phase rotator 126, so that the one-symbol-delayed signal, output from the one-symbol delay unit 112, may be rotated in an opposite direction.
CPE correction by the prior art OFDM signal receiving apparatus 100 may be performed as follows. CP subcarriers of a current OFDM symbol may be multiplied by complex conjugates of subcarriers from a previous OFDM symbol, which may be expressed by Equation (1).
                                                        Ri                                            [                kcp                ]                                      ·            Ri                    -                      1            *                          [              kcp              ]                                      =                                                            ⅇ                                  j                                                        (                                                                  ϕ                        i                                            -                                              ϕ                                                  i                          -                          1                                                                                )                                                                                                                      H                                                              [                      kcp                      ]                                                                                        2                                                          Xi                                                  [                  kcp                  ]                                                          Xi                        -                          1              *                              [                kcp                ]                                              =                                    16              9                                                                                                    H                                                        [                    kcp                    ]                                                                              2                                                  ⅇ                              (                                                      ϕ                    i                                    -                                      ϕ                                          i                      -                      1                                                                      )                                                                        (        1        )
In Equation (1), Ri[k] may represent a signal received after FFT, i.e., a k-th subcarrier of an i-th OFDM symbol. H[k] may represent a channel frequency response to the k -th subcarrier, kcp may represent the location of a CP, and 16/9 represents the power of a CP subcarrier, as defined by the standards specified for DVB-T systems.
A differential phase error, ΔCPEi,i−1, may then be obtained by averaging one OFDM symbol and by extracting the phase of an averaged signal, expressed by Equation (2).
                              Δ                                                                          CPE                          i              ,                              i                -                1                                                    =                              ∠                                      [                                                E                                                        (                                                                  16                        9                                                                                                                                      H                                                                                [                              k                              ]                                                                                                                                2                                                                                ⅇ                                                  j                                                                                (                                                                                ϕ                                i                                                            -                                                              ϕ                                                                  i                                  -                                  1                                                                                )                                                                                )                                                                                ❘                                      k                    ⋐                    kcp                                                              ]                                =                                    ∠ⅇ                              j                                                  (                                                            ϕ                      i                                        -                                          ϕ                                              i                        -                        1                                                                              )                                                      =                                          ϕ                i                            -                              ϕ                                  i                  -                  1                                                                                (        2        )
A CPE, which may be obtained by accumulating differential phase errors, may be calculated using Equation (3).
                              CPE          i                =                                            ∑                              j                =                1                            i                                                                                Δ                                                                                CPE                                  j                  ,                                      j                    -                    1                                                                                =                                    (                                                ϕ                  i                                -                                  ϕ                                      i                    -                    1                                                              )                        +                          (                                                                    ϕ                                          i                      -                      1                                                        -                                      ϕ                                          i                      -                      2                                                        +                  …                  +                                      (                                                                  ϕ                        i                                            -                                              ϕ                        0                                                              )                                                  =                                                      ϕ                    1                                    -                                      ϕ                    0                                                                                (        3        )
The calculated CPE includes a given level of phase offset φ0. However, since the given phase offset φ0 may be compensated for by the equalizer 128, the given phase offset φ0 may have a minimal adverse affect on HDTV system performance.
FIG. 2 illustrates the structure of an OFDM frame; and FIG. 3 is a diagram illustrating the structure of an OFDM symbol. FIGS. 2 and 3 are provided to illustrate the relatively complicated hardware structure of the OFDM signal receiving apparatus 100 of FIG. 1, due to the inclusion of the one-symbol delay unit 112.
As shown in FIG. 2, OFDM symbols may be classified into 2K mode OFDM symbols and 8K mode OFDM symbols according to the FFT sizes specified by the DVB-T standards. As shown in FIG. 3, CPs included within a given OFDM symbol may have corresponding designated locations within the given symbol. These designated locations may be different from designated locations in another given OFDM symbol. Therefore, as seen from a direction of time, one OFDM symbol may be understood as a continuous signal comprised of data, CPs, and transmission parameter signals, as shown in FIG. 3.
In DVB-T 8K mode, an OFDM symbol includes 6817 subcarriers. Supposing that I and Q data are each represented by 10 bits, the one-symbol delay unit 112 thus requires memory capable of storing as many as 136340 bits (6817×10×2=136340). Accordingly, the hardware structure of the OFDM signal receiving apparatus 100 may be cumbersome and require a relatively complex configuration, which may also require additional space or area to accommodate a larger OFDM signal receiving apparatus 100.

Apparatus, method and computer program for correcting common phase error of OFDM signal symbols


A mobile communications system including one or more mobile communications devices and a mobile communications network, the mobile communications network including a radio network part and a core network part and being configured to communicate data packets to and/or from mobile communications devices. Data packets can be communicated to or received from the mobile communications devices using either a broadband packet network or a dedicated messaging network. The dedicated messaging network is arranged to communicate short data grams more efficiently than larger data communications. Therefore by selecting either the dedicated messaging network or the broadband network as a function of content of the data packet a more efficient use of available communications resources and hardware resources is realized.

Mobile communication systems have evolved over the past ten years or so from the GSM System (Global System for Mobiles) to the 3G system and now include packet data communications as well as circuit switched communications. The third generation partnership project (3GPP) has now began to develop a fourth generation mobile communication system referred to as Long Term Evolution (LTE) in which a core network part has been evolved to form a more simplified architecture based on a merging of components of earlier mobile communications network architectures and a radio access interface which is based on Orthogonal Frequency Division Multiplexing (OFDM) on the downlink and Single Carrier Frequency Division Multiple Access (SC-FDMA) on the uplink. The core network components are arranged to communicate data packets in accordance with an enhanced packet communications system.
Third and fourth generation mobile telecommunication systems, such as those based on the 3GPP defined UMTS and Long Term Evolution (LTE) architecture are able to support more sophisticated services than simple voice and messaging services offered by previous generations of mobile telecommunication systems.
For example, with the improved radio interface and enhanced data rates provided by LTE systems, a user is able to enjoy high data rate applications such as mobile video streaming and mobile video conferencing that would previously only have been available via a fixed line data connection. Third and fourth generation mobile communication networks therefore typically employ advanced data modulation techniques on the radio interface which can require more complex and expensive radio transceivers to implement. However not all communications are of a nature which requires the full bandwidth capability of for example the LTE system. Accordingly, it is may be more appropriate to adopt a technique which communicates some types of data as more efficiently than using the full-bandwidth capability of a mobile communications system.

Mobile communications system, infrastructure equipment, base station and method


Methods and systems for a platform development version control system for monitoring contributors to software platform development. The methods and systems generate data analytics on contributors to software platform development using group affiliations as listed in a group directory (e.g., a corporate directory for an entity providing the software platform) as a common organizing factor. For example, by organizing the methods and systems according to the group affiliations, the methods and systems may generate data analytics on contributions of contributors within those groups, irrespective of whether or not the group members are working on the same project. The methods and systems may then provide recommendations and graphical representations based on the data analytics.

Computer programming is typically a team-based activity, in which the responsibilities for the features and source code necessary to produce a given product (e.g., a software application) are shared among team members. To facilitate this team activity, team members may submit contributions to the product to a distributed version control system. This system may include a codebase that features a full history of the product that is mirrored on every contributor's computer. Team members may submit changes to an external repository, which is reviewed before being added to the repository of the codebase. The system may enable automatic management of different branches of the product as well as the merging of different contributions. The team may also utilize one or more issue management and bug-tracking tools. The team may further outsource some issues to software-as-a-service providers. Accordingly, project management for computer programming often involves multiple team members and service providers sharing multiple versions of a single codebase for the project.
In contrast to management of a computer programming project for a product, programming for a platform is far more difficult. Computer programming to create a platform exacerbates the problems of programming for a product while also introducing new ones. For example, a platform may comprise a backbone connecting multiple products together for a given entity. Furthermore, platforms are meant to be more malleable and allow new products and features to be continuously added. As the platform provides the foundation upon which new products are continuously stacked, each contribution to the platform must ensure that no issues are created for the platform, the stacked products, and/or the relationships between different products and/or the platform itself. For example, the platform may act as a foundational service or master data repository that other software and services may use. Thus, any changes to the source code and/or data of the master data repository may affect all products as well as how the products interact with the platform and each other. Therefore, careful monitoring and review of any changes to the master data repository is needed.

This patent is subject to a terminal disclaimer.

Methods and systems for monitoring contributors to software platform development


Videos of a scene are processed for view synthesis. The videos are acquired by corresponding cameras arranged so that a view of each camera overlaps with the view of at least one other camera. For each current block, motion or disparity vector is obtained from neighboring blocks. A depth block is based on a corresponding reference depth image and the motion or disparity vector. A prediction block is generated based on the depth block using backward warping. Then, predictive coding for the current block using the prediction block.

Multiview video coding is essential for applications such as three dimensional television (3DTV), free viewpoint television (FTV), and multi-camera surveillance. Multiview video coding is also known as dynamic light field compression. As used herein, coding can include encoding, decoding or both in a codec, for example.
Depth images are assumed part of the data format in an emerging 3D video coding standard. Using the depth images as side information to perform predictive coding is known as view synthesis prediction (VSP).
In conventional video coding, e.g., coding according to the H.264 AVC (Advanced Video Coding) and H.265 HEVC (High Efficiency Video Coding) standards, motion information from neighboring blocks is used to derive a motion vector. The derived motion vector is then used as a motion vector predictor (MVP) to predict the motion vector for the current block. Then, the motion vector difference (MVD) between the current motion vector and the MVP is encoded and transmitted.
FIG. 1 shows a conventional method to code a current block. Step 110 derives a motion or disparity vector from a neighboring block, referred to as MotionDerive. Step 120 determines a motion or disparity vector, referred to as MotionCurrent, for the current block by applying motion estimation techniques that aim to minimize residual differences. Step 130 calculates and codes the motion vector difference: (MotionDiff=MotionCurrent−MotionDerive). Finally, step 140 codes the residual block.
FIG. 2 shows the corresponding prior-art encoder. Element 201 shows blocks in a portion of a picture. In element 201, a current block is denoted by a star "*", and a neighboring block is denoted by a dot "•". From the neighboring blocks as shown in element 201, derive 202 a motion vector or disparity vector. The derived motion or disparity vector from 202 serves as motion vector predictor (MVP) 203.
By referencing the texture reference picture buffer 204, motion estimation is performed 205 for the current block to produce a motion vector (MotionCurrent) 206 for the current block.
After calculating 207 the difference between MVP and MotionCurrent, a motion vector difference (MVD) 208 is obtained, which is encoded 209 into the bitstream 210.
Another output from motion estimation 205 is the reference picture, which serves as texture predictor 211. Then, the texture residual 211 is obtained by performing 212 texture prediction based on the texture predictor 211 and the current picture 215. The texture residual 213 is also encoded 214 as part of the bitstream.
FIG. 3 shows the decoder. From the neighboring blocks as shown in element 301, derive 302 a motion vector or disparity vector. The derived motion or disparity vector serves as the motion vector predictor (MVP) 303.
From the coded bitstream 310, motion vector difference (MVD) 308 is decoded 309 and fed to an adder 307. The motion vector predictor 303 and motion vector difference 308 are added 307, and the motion vector used for the current block MotionCurrent 306 is then obtained.
From the coded bitstream 310, the texture residual picture 313 is decoded 314. The current motion vector 306 and the texture residual picture are inputs to the motion compensation module 305. Together with texture reference buffer 304, the motion compensation is performed, and finally the decoded picture is outputted 315.

Method and system for backward 3D-view synthesis prediction using neighboring blocks

Mitsubishi Electric Research Laboratories, Inc.


A mobile terminal and a control method of a mobile terminal are disclosed. The mobile terminal and a control method thereof provide a user interface allowing for a user to easily and effectively control the mobile terminal through an interaction between a certain case and the mobile terminal when the mobile terminal is accommodated in the case in a lock mode.

Field
The present invention relates to a mobile terminal and a control method thereof.
Related Art
Recently, various functions have been provided to users according to a remarkable advancement of software and hardware in various electronic device fields including mobile terminals.
Thus, the necessity of developing and supplying of multiple user interfaces allowing users to easily and effectively control a mobile terminal providing diverse, complicated functions is increasing.


A golf shaft is attached to a removable sphere at a first end portion below an offset in the shaft. The sphere is mounted within a pocket of a top portion of a putter head and seats within a first cavity in a bottom portion of the putter head when the top and bottom portions of the putter head are joined. Set screws located in the bottom portion of the putter head retain the sphere and a half sphere located in a second cavity in the bottom portion seated in place. Retraction of the set screws to the sphere permits movement of the shaft so that its angle with respect to the putter head can be adjusted.

1. Field of the Invention
This invention relates to a golf putter. More particularly, it relates to a golf putter with an adjustable shaft to adjust the angle of the shaft with respect to the putter head and a variable weight distributing putter head.
2. Description of Prior Art
The principal of adding weights to putter heads and providing a means to transfer the shaft connection in the putter head to accommodate either a right handed or left handed golfer is well known as seen from U.S. Pat. Nos. 3,397,888, 5,116,047 and 5,121,922.
In U.S. Pat. No. 3,397,888, a golf club has a shaft which can be inserted into a hole selected from a linear row of holes on two separate surfaces of the club head. This permits the use of the club by either a right or left handed golfer and provides for selection from two different golf faces for use in striking a golf ball.
In U.S. Pat. No. 5,116,047, the putter head has three threaded holes so that an end of the golf shaft can be locked in place in any one of the holes to permit use of the putter for either a right handed or left handed golfer. In addition, two weights can be added to the putter head.
In U.S. Pat. No. 5,121,922, there is a rearwardly extending head portion containing weights to alter the center of gravity of the putter head.
While the prior art patents are useful for their intended purpose, golfers are continuously on the look out for improved putters which will enhance their putting skills. Such an improved putter is the subject of the present invention.


A coupling circuit, including: a coupler including a first conductive line and a second conductive line coupled to the first one; at each end of the second line of the coupler, a two-output signal splitter; and at each output of each splitter, a filtering function.

1. Technical Field
The present disclosure generally relates to electronic circuits and, more specifically, to radio transmit-receive chains. The present disclosure more specifically relates to the forming of a wide-band coupler.
2. Discussion of the Related Art
Couplers are circuits intended to extract part of the power conveyed by a transmission line for measurement purposes. In an application to radio transmission chains, the coupler typically has the function of controlling the gain of a transmit amplifier or the parameters of an impedance-matching network according to the response of the antenna.
There are two large categories of couplers. So-called lumped element couplers, which are formed of resistive, inductive, and capacitive components, and so-called distributed couplers, which are formed of coupled conductive lines. The present disclosure relates to the second category of couplers.
The multiplication of frequency bands capable of being processed by telecommunications device raises issues in terms of parasitic coupling between antennas dedicated to these different bands, and in particular when frequency bands overlap.


A messaging system implements a group call in a controller (110, 120) by receiving (306) first and second messages intended for first and second recipients and determining (416) that the first and second messages are identical to one another. In response to making that determination, the controller transmits (522) the first and second messages as a single group call message.

With the growing use of email and personal computer software applications to interface to messaging systems, messages are being sent to ad hoc groups at an increasing rate. Message originators commonly use email to send a message to a group of recipients informing them of upcoming meetings, breaking news, lunch plans, and the like. The airtime required for long messages sent to multiple recipients is large, and messaging service providers are anxious to find a way to combine such messages into a single transmission whenever possible.
Some messaging protocols provide a mechanism to allow an unlimited number of recipients to receive the same message. Motorola's FLEX.TM. protocol, for example, can use individual addresses to send each recipient an instruction to listen at a future time and to use a temporary address shared by all the recipients. This is referred to as a dynamic group call. Unfortunately, current network interface protocols do not provide a mechanism for instructing messaging system controllers to form dynamic group call messages. Nor do current controllers have the ability to implement dynamic group call messages on their own initiative.
Thus, what is needed is a method and apparatus that will allow the implementation of dynamic group call messages in messaging systems. The method and apparatus preferably should perform automatically to detect messages that can be combined, and to combine such messages by transmitting them as a dynamic group call message when doing so will save airtime.

Method and apparatus in a messaging system for implementing a group call


A tube lens includes a singlet and a doublet with a long front tube length between a lens stop and the tube lens. The front tube length is 1.0 to 1.5 times an effective focal length of the tube lens. The front tube length provides sufficient space for an optical platform, a folding mirror, and a telescope. The telescope rotates between a 2× mode with front and back doublets and a 1× mode with a clear aperture. The field angle of the tube lens is 4.0 degrees. Specific glass types correct the lateral color in a system for digital pathology with a white LED and a color CCD sensor. The system for digital pathology further includes an objective lens with a numerical aperture at 0.50-0.55, and a Kohler illumination system with a numerical aperture of critical illumination at 0.75-0.85 times the numerical aperture of the objective lens.

Haemotoxilyn and Eosin: Two of the most common tissue stains in pathology are haemotoxilyn and eosin. FIG. 1 displays the spectral transmission of tissue components stained with haemotoxilyn and eosin. The data of FIG. 1 is from the following article: Bautista, Abe, Yamaguchi, Yagi and Ohyama, "Digital staining of pathological tissue specimens using spectral transmittance," Proc. of SPIE Vol. 5747, 1892-1903 (2005).
Color Human Vision: Color vision in humans is typically described with a small set of spectral lines. The relevant spectral lines for the invention disclosed herein are as follow: g (436 nm), F (486 nm), e (555 nm), d (588 nm), and C (656 nm). The relative sensitivities of human vision at these lines are roughly: 7% at g, 24% at F, 100% at e, 68% at d, and 5% at C.
Human vision has poor spatial resolution at blue wavelengths. The fovea of the retina contains very few blue cones while the smaller foveola contains none. Human vision is largely based upon the red and green cones. These cones are commonly designated by wavelength as short (blue), middle (green) and long (red).
In a typical optical design for human vision, the F (486 nm), d (588 nm), and C (656 nm) spectral lines are specified. These three lines include a small portion of the blue range (440-490 nm). The g (436 nm) line is frequently ignored due to lack of blue sensitivity and blue resolution in human vision.
Color Machine Vision: Color machine vision is defined by the spectrum of the source and sensitivity of the detector. FIG. 2 displays the relative color sensitivity of the combination of a white LED and a color CCD. The LED is a CBT-90 by Luminus Devices, Inc. of Billerica, Mass., USA. The CCD is a KAI-08050 by the Eastman Kodak Company of Rochester, N.Y., USA.
A CCD sensor has large sensitivity at both the g and F lines. The quantum efficiencies of the color KAI-08050 sensor are: 38% at the g line, 45% at the F line, 20% at the d line, and 30% at the C line. The blue channel is more sensitive than the green or red.
A typical white LED comprises a blue gallium-nitride LED with phosphor coating. The emission spectrum comprises a peak at 450 nm from the LED, and broad phosphorescence from 450 nm to 700 nm.
The typical dyes of pathology are haemotoxilyn and eosin. The typical dyes of pathology create images with strong components at the g and F lines.
Correction of the g-line in film or CCD sensors requires the use of special glass. A combination of long crown and short-flint is common in objective lenses for both photography and microscopy.
There are two common formats of color vision by CCD sensors. A first format of color vision employs three CCD sensors and two beamsplitters. Consistent orientation of the images to the CCDs requires precise alignment of optical hardware, which is difficult and expensive. A shifted or rotated image requires interpolation for conversion to the correct location and angle. The sampling rate is defined by the width of a single pixel. A second format of color vision employs a Bayer pixel which comprises 1 blue pixel, 2 green pixels, and 1 red pixel. The image sampling rate of a Bayer is defined by the width of 2 pixels.
Glass Types: The refractive index of glass is defined by dipole current. A dipole comprises positive and negative charge with finite separation. The electric field of a dipole counters the external field of the electromagnetic wave. The opposing electric field of the dipole drives the total electric field back to zero faster than outside of the glass. Thus, the dipole current shortens the spatial wavelength. The effects of dipole current upon wavelength are represented by refractive index.
The growth in refractive index within a wavelength range is described by dispersion. The Abbe number defines dispersion as
            v      d        =                            n          d                -        1                              n          F                -                  n          C                      ,
wherein n specifies the refractive index according to spectral lines. Partial dispersion defines the growth in refractive index of a first range as a fraction of growth in refractive index of a second range. An example of partial dispersion is
      P    gF    =                              n          g                -                  n          F                                      n          F                -                  n          C                      .
The normal partial dispersion of glass types is defined by Schott North America, Inc. of Elmsford, N.Y., USA (hereinafter "Schott") asPgFn=+(0.6438)−(0.001682)νd.
The relative partial dispersion is defined by a departure from the normal partial dispersion as below.ΔPgF=PgF−PgFn
A crown glass employs tightly bound electrons with a resonant frequency in the near ultraviolet range. Consequently, a crown glass displays a refractive index that grows faster at shorter wavelengths. A crown glass displays a normal dispersion with nearly zero relative partial dispersion. Examples of crown glass are borosilicate and fused silica. A long crown employs tightly bound electrons with a resonant frequency in the deep ultraviolet. Consequently, the refractive index is smaller than crown glass, and the dispersion is very small as represented by a large Abbe number. The relative partial dispersion of a long crown is positive. The "long spectrum" is due to a large spectral separation of absorption peaks. Examples of long crown are fluorophosphate glass and calcium fluoride crystal. Both materials are more expensive and more difficult to process than crown glass.
A short flint employs defects that reduce the lifetime of dipole oscillations. Consequently, the amplitude of the dipole current grows less rapidly while approaching resonance, and the partial dispersion is reduced. The relative partial dispersion of a short flint is negative. Consequently, a short flint may counter the partial dispersion of a crown. The reduced dipole current also indicates a broadening of the ultraviolet absorption band. This broadened absorption band shortens the spectral length between absorption bands. The broadened ultraviolet absorption band might penetrate the blue spectrum. A broadened spectrum of the infrared band has no effect upon the red spectrum. Examples of short flint are lead borate, and niobium silicate. A recently developed short flint is zirconium-doped tantalum silicate.
A lanthanum flint employs the tightly bound electrons of a rare earth metal. The high atomic number of a rare earth metal provides a much larger electron density than a long crown. A lanthanum flint typically displays a negative relative partial dispersion.
A dense crown provides a higher refractive index than a crown or long crown. The higher refractive index can reduce astigmatism and spherical aberration. A dense crown typically displays a positive relative partial dispersion.
A dense flint provides a higher refractive index than a crown or long crown. The higher refractive index can reduce astigmatism and spherical aberration. A dense flint displays increasing dispersion at shorter wavelengths. Consequently, the benefits of a dense flint often create more lateral color in the blue spectra.
Recent developments of short flints were motivated by ecological concerns about lead borate. The use of niobium, tantalum, and zirconium has created new short flints with superior qualities. In particular, N-KSFS11 by Schott employs zirconium-doped tantalum oxide within a largely silica glass network. The tantalum oxide provides a higher refractive index than past short flints. The zirconium doping shortens the resonant lifetime of the tantalum oxide. Other vendors such as Ohara Inc. of Japan (hereinafter "Ohara") did not employ zirconium doped tantalum oxide as of 2011. Thus, N-KSFS11 was unique to Schott North America, Inc, at least as of 2011.
CCD Size: A KAI-08050 sensor by the Eastman Kodak Company of Rochester, N.Y., USA (hereinafter "Kodak") employs four CCDs on a single chip. The sensor diagonal is 22.66 mm. Each sub-sensor has its own external circuitry. A large CCD is desired for rapid mapping of a large specimen such as a tissue specimen. However, the large angular size of the KAI-08050 detector occupies a compromised portion of the field of tube lens in the prior art. Thus, implementation of a larger CCD with 25 mm diagonal has been limited by the quality of the tube lens. In particular, the lateral color of tube lens is compromised at field margin. Astigmatism and Petzval curvature of the tube lens are also common at large diagonals of 25 mm.
20× Objective Lens: A popular objective lens for pathology is an apochromat, such as part number UPLSAPO 20×, by Olympus America, Inc. of Center Valley, Pa., (hereinafter "Olympus") at 20× at 0.75 NA. Herein, the vision NA is defined by the objective NA. The brightness of the image background is determined by the 0.75 NA of vision when the NA of illumination is larger. However, the resolution is not determined by 0.75 NA of vision. The typical cover strata of a tissue specimen create spherical aberration beyond the correction of the objective lens. Consequently, the diffraction limit of the objective is circa 0.50 NA. The annular NA of vision from 0.50 to 0.75 provides space for an illumination lens stop at 0.60 NA. A properly designed vision lens-stop at 0.50 NA can stop the illumination at 0.60 NA to 0.50 NA without scatter by the inside faces of the glass elements. A sharp edge to aperture defines a proper design for a vision lens stop. The effective NA of illumination at 0.50 can precisely match the NA of vision without background fog from scatter.
The measured densities of glass components of the Olympus UPLSAPO 20× indicate fluorophosphate and niobium silicate as two of the glass types. The fluorophosphate is a long crown, and the short flint is a niobium silicate. Thus, the apochromat at 20× at 0.75 NA includes long crown and short flint as glass types.
Critical Illumination: In 1875, Nelson empirically determined that an optical system is spatially incoherent when the illumination NA exceeds 0.75 times the vision NA. This condition defines the "critical illumination" of Nelson. In practice of the current invention, an illumination NA at 0.80 times the vision NA creates a small edge overshoot which is highly beneficial to image quality. The edge overshoot is created by a negative partial coherence between adjacent point spreads of the objective lens. The partial coherence of the illumination field is defined by the Fourier transform of the angular profile of the source. Thus, a nominal range for Nelson's critical illumination is defined as an illumination NA at 0.75-0.85 times the vision NA. Nelson employed an image of the source at the object of illumination. Consequently, numerous authors erroneously indicate "critical illumination" as a source image located at the object. Thus, "critical illumination" must be defined by the relation of illumination NA to objective NA.
Kohler Illumination: In 1893, Kohler defined an illumination system with the source image at a great distance from the object of illumination. Typically, the distant image of the source is created by location of a source image at the front focal point of the condenser lens. However, the lens stop of the objective lens is frequently not located at the back focal point of the objective. Thus, the location of the source conjugate must be carefully considered.
A Kohler illumination system is defined by Seward in Optical design of microscopes published by SPIE Publications in 2010. There, the illumination system has a source, a source lens, an illumination field stop, an illumination lens stop, a condenser lens, and an illumination field. The Kohler illumination system creates a distant image of the source from the illumination field.
Bistable Telescope: There are two common formats of a refractive telescope: a Keplerian, and a Galilean. A Keplerian telescope employs an objective lens and ocular lens, both with positive power. A Galilean telescope employs an ocular lens with negative power. A Galilean telescope is shorter than a Keplerian telescope at the same magnification. The reduction in length between Galilean and Keplerian telescopes is twice the effective focal length of the ocular lens. The shorter path length of a Galilean telescope is preferred in the tube of a microscope.
The prior art contains examples of telescopes within microscopes. For example, U.S. Pat. No. 4,195,903 to Kawase describes a rotatable Galilean telescope within the tube region of an infinity-corrected microscope. In U.S. Pat. No. 4,673,973, Ledley describes a Galilean telescope within one arm of a split optical system.
The bistable telescope is related to numerous patents. In U.S. Pat. No. 3,804,506, for example, Fletcher describes a camera shutter with rotary solenoids operative to actuate shutter blades. An inertial damper and a stop plate are built into each solenoid to prevent shock and rebounding.
With U.S. Pat. No. 4,262,989, Waters teaches changeable sets of Galilean optics mounted on a rotary shaft that is rotated by a rotary solenoid. Three magnifications are achieved by a single Galilean telescope at three orientations: forward along the optic axis, backward along the optic axis, and across the optic axis. The shaft and the optics are fixed at angular dispositions by engagement of a detent ball with grooves in a detent plate.
U.S. Pat. No. 7,245,425 to Miyashita is directed to an optical system with an objective lens and an intermediate magnification varying part in the form of a telescope. The telescope rotates by 180 degrees to reverse direction. At magnification of 1.4×, the telescope achieves a 2× change in magnification between modes. The system also includes a reduction stop in one mode.
Nyquist Parameters: The cut-off frequency of a diffraction-limited objective lens is
      f    CO    =                    2                                                  NA            λ        .
At 0.588 um, the cutoff frequency for the diffraction-limited 0.50 NA objective is 1.70 cycles per um. The Nyquist rate is the minimum sampling rate at which there is no overlap of the replicated spectra. The replicated spectra are centered at the harmonic frequencies of the sampling wave form. An overlap between replicated spectra creates aliasing. The Nyquist rate at 0.50 NA and 0.588 um wavelength is 3.4 cycles per um. FIGS. 3A and 3B display examples of replicated spectra with and without aliasing.
In FIG. 3A, an 11.00 um pixel and 20× magnification defines the sampling frequency as 1.82 cycles per um. There is significant aliasing from the replicated spectrum. The optical transfer function (OTF) of the irradiance is defined as the addition of the replicated spectrum to the original spectrum. Thus, the OTF is artificially large near the cut-off frequency at 1.70 cycles per um. The magnitude of the replicated spectrum is defined by the duty cycle of the pixel sampling pattern. Thus, the magnitude of the replicated is smaller than unity. At any magnitude of the replicated spectrum, the aliasing creates an artificially large OTF near the cut-off frequency at 1.70 cycles per um.
In FIG. 3B, an 11.00 um pixel and 40× magnification defines the sampling frequency as 3.64 cycles per um. There is no aliasing from the replicated spectrum. Thus, the optical transfer function (OTF) is a true description of the optical system up to the onset of replicated spectrum. The original spectrum may extend to one-half of the sampling frequency without aliasing. This condition lays the foundation for the Nyquist frequency, which has been defined as one-half of the sampling frequency. The Nyquist frequency represents the largest spatial frequency that can be sampled without aliasing. In a system with an 11.00 um pixel, the Nyquist frequency is 0.91 cycles per um at 20× as FIG. 3A, and 1.82 cycles per um at 40× as in FIG. 3B. The Nyquist frequency at 40× exceeds the cut-off frequency at 1.70 cycles per urn, while the Nyquist frequency at 20× does not.
The Nyquist parameters of the current invention are summarized in Table 1 below. The 11.0 um pixel is defined by use of the Bayer pixel of a Kodak KAI-08050 as referenced hereinabove, which has a pixel size of 5.5 μm. Clearly, the 40× mode satisfies both Nyquist conditions for sampling without aliasing, while the 20× does not. A 0.50 NA microscope with 11.0 um Bayer pixel displays aliasing. Thus, a 2× telescope is essential for the elimination of aliasing in a typical 20× microscope for pathology.
TABLE 1Nyquist parameters of the 20X and 40X magnificationsParameterValuePixel5.50 μmBayer pixel11.00 μmProjected Bayer pixel at 20X0.55 μmProjected Bayer pixel at 40X0.28 μmCut-off frequency (588 nm, 0.50 NA)1.70 cyc/μmNyquist rate (2X cut-off fequency)3.40 cyc/μmSampling frequency at 20X1.82 cyc/μmSampling frequency at 40X3.64 cyc/μmNyquist frequency at 20X0.91 cyc/μmNyquist frequency at 40X1.82 cyc/μm

Tube lens with long front tube length within optical system for digital pathology


A radio frequency (RF) power divider/combiner circuit prevents an unbalance in current consumption according to a variation of the load, and reduces size of a power amplifier when employed therein. In an exemplary embodiment, the RF power divider/combiner circuit includes an input terminal, first and second output terminals, a first microstrip line connected to the input terminal and a second microstrip line vertically connected to the first microstrip line. A first capacitor is connected between a middle of the second microstrip line and ground. A first inductor has a first end connected to an end of the second microstrip line, a second inductor has an end connected to another end of the second microstrip line, and a second capacitor is connected between a second end of the first inductor and a second end of the second inductor. A third microstrip line is connected between the second end of the first inductor and the first output terminal, a fourth micro-strip line is connected between the second end of the second inductor and the second output terminal, and a resistor is connected in parallel with the second capacitor.

1. Field of the Invention
The present invention relates to a radio frequency power divider/combiner circuit, and more particularly to a radio frequency power divider/combiner circuit realized by using a microstrip line and lumped elements.
2. Description of the Related Art
In a conventional radio communication system, a power divider/combiner circuit (i.e., divider or combiner circuit) is generally used in a radio frequency (RF) power amplifier. Typically both a divider and a combiner are used--the divider divides an input signal into two or more divided signals, where each divided signal is applied to the input of a separate RF power transistor for amplification; and the combiner combines the output power of the power transistors. Such a power divider/combiner circuit is realized by using a micro-strip line, or a 3 dB hybrid coupler.
The power divider/combiner circuit which is realized by printing a transmission line (e.g., microstrip line) on a substrate, is designed to convert impedance by using a .lambda./4 line (where .lambda. is wavelength). In this case, input and output terminals of a power divider are respectively composed of 50.OMEGA. lines, and the .lambda./4 line is designed as a 70.7 .OMEGA. transmission line to achieve impedance matching. An example of this type of power divider is a "Wilkinson" type power divider.
It is known that the electrical length of a transmission line is determined based on a functional relation of the substrate permittivity and the operating frequency. That is, the physical length of a .lambda./4 transmission line needs to be longer for a relatively lower substrate permittivity and operating frequency. Therefore, it is difficult to realize the .lambda./4 line within a limited space (substrate) in an ultra high frequency (UHF) band. If the power divider/combiner is realized at UHF by using a .lambda./4 line such as in the Wilkinson divider, the power amplifier becomes too large in size for certain applications.
FIG. 1 illustrates a power amplifier which is realized by using a 3 dB hybrid coupler (or a 90.degree. hybrid coupler). In the drawing, an RF signal input from an input terminal INPUT is applied to a hybrid input circuit 110. A resistor R having a resistance of 50 ohms is connected between input terminal ISO and the hybrid input circuit 110. The signals at output terminals, points A and B, of the hybrid input circuit 110 have equal RF power and a 90.degree. phase difference. These signals are inputted to input matching circuits 112A and 112B which provide output signals to transistors 114A and 114B, respectively, which in turn provide output signals to output matching circuits 116A and 116B. In the power amplifier shown in FIG. 1, the current consumption of transistors 114A and 114B becomes different from each other, according to a characteristic, i.e., a return loss of the load. The different current consumption may cause serious damage to one of the transistors having the higher current consumption. As a result, the power amplifier will not operate or will generate decreased output power at terminal OUTPUT of hybrid output circuit 120. A resistor R having a resistance of 50 ohms is connected between the hybrid output circuit 120 and output terminal ISO.
It can be appreciated from the Smith chart shown in FIG. 2 that the current consumption varies according to the characteristic of the load. For instance, consider an impedance locus 202 with an output power being lower by about 1 dB than output power at an optimal point 201 at which the maximum power of the power amplifier is generated, in light of its characteristic. Here, if it is assumed that a reflection coefficient of the output load is a constant, i.e., k, which is generally derived by taking into consideration the resistivity of the load, i.e., .rho..sub.L, the reflection coefficient looking into a point A of FIG. 1, i.e., .GAMMA.A, is represented by .GAMMA.A=k+.theta., where .theta. is the phase of the signal inputted into point A, and the reflection coefficient looking into a point B, i.e., .GAMMA.B, is represented by .GAMMA.B=k+.theta.+180.degree.. For example, if the current has a relationship of I2<I1=I3<I4, where points 1, 2, 3, and 4 represent points on the impedance locus 202 corresponding to the current values I1, I2, I3 and I4, respectively, which show the variation of current consumption as a function of the load, as shown in FIG. 2, the reflection coefficient .GAMMA.A corresponds to a position (4) and the reflection coefficient .GAMMA.B corresponds to a position (2). As a result, the transistor 114A (see FIG. 1) has the minimum current consumption and the transistor 114B (see FIG. 1) has the maximum current consumption, thereby resulting in the maximum current consumption difference between the two transistors. Then, a junction temperature (hot spot) of the transistor 114B increases, which results in serious damage to the transistor 114B.
As described above, if the power amplifier is realized in microstrip line, the power amplifier increases in size undesirably at lower operating frequencies such as the UHF band. Further, if the power amplifier is realized by using the 3 dB hybrid coupler, the outputs and the current consumption of the transistors 114A and 114B of the power amplifier vary according to the load characteristic (i.e., the reflection coefficient).

Radio frequency power divider/combiner circuit having conductive lines and lumped circuits


A high-tension steel sheet suitable for deep drawing and having superior surface treatment characteristics is made of a steel consisting essentially of, by weight: 0.001 to 0.05% of C; not more than 1.0% of Si; not more than 2.5% of Mn; 0.05 to 1.0% of Mo; one or both of 0.001 to 0.2% of Nb and not more than 0.3% of Ti, wherein Ti*%+(48/93)Nb%.gtoreq.(48/12)C% in which Ti*%=Ti%-(48/32) S%-(48/14)N%, wherein, when Ti*%<0, Ti*% is regarded as being 0; 0.0005 to 0.01% of B; 0.01 to 0.10% of Al; not more than 0.15% of P; not more than 0.010% of S; not more than 0.006% of N; Si, Mn and P meeting the condition of 0.2<(Si%+10P%)/Mn%<3.3; and the balance substantially Fe and incidental impurities. This steel sheet is produced by a process which includes: hot-rolling the steel slab to obtain a hot rolled steel strip at a final hot-rolling temperature not lower than the Ar.sub.3 transformation temperature; coiling the steel strip at a temperature not lower than 300.degree. C. but not higher than 615.degree. C. when Nb is not contained and not lower than 500.degree. C. but not higher than 700.degree. C. when Nb is contained; cold-rolling the steel strip to obtain a cold rolled steel strip at a rolling reduction not smaller than 65%; and recrystallization-annealing the cold rolled strip at a temperature not lower than the recrystallization temperature but below the Ac.sub.3 transformation temperature.

1. Field of the Invention
The present invention relates to a cold-rolled high-tension steel for deep drawing suitable for use as the materials of automotive inner and outer panels. The steel has a ferrite single-phase structure, exhibits a tensile strength not lower than 40 kgf/mm.sup.2 and has excellent forming workability, as well as superior surface treatment characteristics. The invention also is concerned with a method for producing such a cold-rolled high-tension steel sheet.
2. Description of the Related Art
Cold-rolled steel steels have been used as materials of automotive parts such as structural members and outer panels. In particular, cold-rolled high-tension steel has been used as the material of such steel sheets in order to meet the requirement for reducing the weight of automobile. Important requisites for cold-rolled high-tension steels for use in automobiles are high forming workability, in particular press-workability, strength large enough to provide security of automobiles, and anti-secondary embrittlement characteristic which prevents embrittlement which may occur during secondary processing conducted after the forming work. In recent years, there is an increasing demand for rust prevention of steel sheets and, therefore, surface treating characteristics of the steel sheets are also becoming a matter of great significance.
Legal controls on total exhaust emissions from automotive engines are becoming more strict, which naturally requires reduction in weights of automobiles for reducing fuel consumption. In order to cope with such a demand, it is very important to develop light-weight and strong steel sheets.
Hitherto, various high-tension steel sheets having excellent workability have been proposed. For instance, Japanese Patent Laid-Open No. 57-181361 discloses a cold-rolled steel sheet which has a high Young's modulus and which is suitable for large-size works, as well as a method of producing such a steel sheet. Japanese Patent Laid-Open No. 58-25436 discloses a method of producing a cold-rolled steel sheet which is suitable for deep drawing and which has a high resistance to aging, as well as small anisotropy. These steel sheets are very-low-carbon steels containing a small amount of Nb and Ti and are produced through a continuous annealing conducted under specific conditions. These steels further contain P as reinforcement elements, in order to develop higher tensile strength.
The present inventors have conducted tests on several high-P steels having compositions similar to those shown in the above-mentioned Japanese Patent Laid-Open publications and found that such steels commonly exhibit a reduction in the mean Lankford value after cold-rolling and annealing, as well as inferior performance after painting.
Very-low-carbon steels having a high P content, in particular those having a C content less than 0.002 wt. %, exhibit tensile strength which is 40 kgf/mm.sup.2 at the highest, which is still too low to meet the requirements for steel sheets to be used as automotive parts having reduced weight and high strength.
Japanese Patent Publication No. 63-9579 discloses a high-strength cold-rolled steel sheet which contains, as a reinforcement element, Cu in addition to P and which exhibits high tensile strength not smaller than 40 kgf/mm.sup.2, as well as a high quality sheet surface. This steel sheet, however, still exhibits inferior surface treatment characteristics.

Cold-rolled high-tension steel sheet having superior deep drawability and method thereof


A device (20) comprising a pressure measurement surface (28) functionally attached to a proof body (22) and a rigid component (30), functionally attached to the proof body (22), the measurement surface (28) forming a surface of the rigid component (30). In addition, the device comprises a support (38), functionally separated from the proof body (22), of generally annular shape, housing the rigid component (30) and a flexible mass (40) radially inserted between the support (38) and the rigid component (30) such that the contour of the measurement surface (28) is bounded by the flexible mass (40), this flexible mass (40) adhering to the support (38) and to the rigid component (30).

It is known that tires can be manufactured by heating a rubber-based raw blank of the tire in a mould of generally annular shape around an axis of revolution. The heating of the raw blank leads to its vulcanization.
More particularly, during vulcanization, the pressure exerted by the mass of rubber on an inner wall of the mould must be checked, especially to determine the transition from raw state to cured state of the mass of rubber.
It is known that this pressure can be checked using a pressure sensor comprising for example a box equipped with a lateral wall and an end side forming a pressure measurement surface on which the pressure to be measured is exerted. The box is also intended to house a proof body functionally attached to the measurement surface.
Traditionally, the measurement surface deforms itself under the effect of a pressure force and transmits this mechanical deformation to the proof body which converts this deformation into a physical quantity intended for a detector sensitive to this quantity.
In order to measure the pressure exerted by the rubber on the inner wall of the mould, the pressure sensor is inserted in a housing provided for this purpose inside the mould such that its measurement surface is in contact with the rubber.
When the blank is raw, however, a rubber residue may flow inside the sensor housing, especially along the outer wall of its box. During vulcanization, this rubber residue may expand and exert a pressure on the wall of the box deforming the wall as well as the sensor measurement surface.
This unwanted deformation of the measurement surface generates incorrect pressure measurements.

Pressure measurement device and mould for vulcanizing rubber for tires


A method for manufacturing a sheet heating element includes preparing a sheet member containing a metal or alloy, and performing anodic oxidizing treatment on the sheet member until only a surface layer of the sheet member is oxidized while a center portion thereof is not oxidized.

(i) Technical Field
The present invention relates to a method for manufacturing a sheet heating element, a fixing device, and an image forming apparatus.
(ii) Related Art
In the related art, sheet heating elements are used in order to heat the inside of a tubular member of a pipe or the like.
As the sheet heating elements, there is known 1) a sheet heating element having a structure in which a heating element made of a nichrome wire or a stainless steel wire is covered with silicone rubber.

Method for manufacturing sheet heating element, fixing device, and image forming apparatus


A cold-cathode discharge tube having an anode and a cathode is provided with a proximity conductor which is divided into a first and second proximity conductor members arranged on the outer bottom surface of the discharge tube below the cathode and below the anode respectively. A high voltage is applied to the first conductor member below the cathode, and the second conductor member below the anode is grounded.

While liquid crystal displays are in wide use in recent years, liquid crystals per se are not luminescent, so that for use in the dark, the liquid display needs to be provided with a backlight at a rear portion thereof for the user to view presentations with the light passing through the liquid crystal. Cold-cathode discharge tubes having a long life are chiefly used as such backlights. With these cold-cathode discharge tubes, however, initiation of discharge causing stabilized firing due to estabilished discharge after energization is dependent on the number of electrons or cations remaining within the tube. Accordingly, if the amount of electrons or cations present is insufficient, there arises the problem of delayed initiation of discharge. Electrons and cations are produced primarily by external light, so that in the case where the liquid display is used as incorporated in other devices, external light through the liquid crystal is not expectable, and the problem becomes more serious owing to scarcities of electrons and cations.
FIG. 21 shows a discharge tube 1 which is provided with a conductor 2 as is already known to overcome the above drawback ("Shomei Kogaku (Illumination Engineering)," edited by Denki Gakkai, p. 72, published by Ohm Co., Ltd. in Jul., 1963). With reference to the drawing, the discharge tube 1 has a cathode 3 at its one end and an anode 4 at the other end thereof. The conductor 2 is adhered to the outer bottom surface of the tube 1 to extend from below the cathode 3 to below the anode 4. (Such a conductor is positioned close to the cathode and anode and will hereinafter be referred to as a "proximity conductor.") The cathode 3 and the anode 4 are connected via a switch 5 to a d.c. power source 6, the high-voltage side being connected to the anode 4, and the ground side to the cathode 3. The proximity conductor 2 is at the same potential as the cathode 3. The discharge tube 1 has a vacuum inside thereof and has small amounts of mercury and argon gas enclosed therein.
When a high voltage is applied to the anode 4 by closing the switch 5, a high electric field is set up across the anode 4 and a portion of the proximity conductor 2 close to the anode 4 since the conductor 2 has the same potential as the cathode 3, highly accelerating electrons and cations present in very small amounts within the discharge tube 1. While migrating toward the anode 4, the accelerated electrons vigorously collide with mercury atoms. A majority of accelerated cations vigorously collide with the proximity conductor 2. These collisions produce secondary electrons, which further collide with mercury atoms to cause emission of additional secondary electrons. Repeated collisions thus taking place produce rapidly increased quantities of electrons and cations, leading to expedited initiation of discharge. Nevertheless, the conventional method of FIG. 21 is not fully effective; many discharge tubes thus adapted still include some which can not be initiated into operation without a delay.

Device for initiating discharge of cold-cathode discharge tube


A system software solution for testing various network elements/entities and processes in a telecommunications network is provided. A network under test contains network entities which save data to a common database that is associated with processing particular test cases. A server correlates database data from the network under test and compares it to anticipated test case results. A disposition of the test cases is determined. Various elements of the invention interface appropriately, and process accordingly, to accomplish the testing and test result(s) disposition. In addition, the test system provides a means to verify billing records within the telecommunications network. Integrated into the system is logic that captures timepoints associated with critical events in a phone call from a test application perspective (particularly the events important to correct billing) and comparing those timepoints with actual results from the tested network. Timepoints are time information with milestones in the progress of call processing. Time information of applicable network elements is first assured to be synchronized, or translated for consistency. The test application timepoints are gathered, compared to billing records associated with the test case (e.g. call), and used to produce an accurate test case result.

Testing telecommunication services can be a laborious and time-consuming task. This is especially true in today's environment where a wide variety of new telecommunication services are being deployed on a rapid basis. Further, the increased use of intelligent network elements including automation devices such as audio response units (ARUs), and intelligent switches such as automatic call distributors, complicate the task of testing new telecommunication services. Telecommunication services are typically tested and re-tested at various stages throughout the development process.
For example, as new services are being developed they are typically modified and refined on a frequent basis. The modifications are generally based on several factors including marketing studies, customer feedback, hardware and software design changes, and network element changes. To implement such modifications during the development cycle, product development organizations modify the software that drives the various network elements used to support the new service. The modified software versions are then released to testing organizations that are responsible for verifying the functionality and performance of the new service. Accordingly, during a typical product development cycle, many different software versions may be released to the testing organizations as the features and functions of the new service evolve.
Thus, testing organizations typically perform many iterations of various test activities to verify that new services operate as designed and do not adversely affect existing telecommunication services. The dynamic nature of the development of new services, and the time-to-market pressures imposed upon the telecommunications industry, drive the need for timely and efficient test procedures.
Often these requirements are met by automating test procedures. Once test cases are automated they can be repeated with minimal effort. This automation facilitates regression testing, which verifies common features among different software versions. In addition, automated test cases are generally more reliable than manual test cases due to the reduction of human factor errors. Further, automated test systems are more efficient and reliable because they execute test cases repeatedly in exactly the same manner.
However, in order to gain the maximum benefit from automation, test cases must be designed for execution without human interaction. This not only reduces test staff requirements, but also enables one to run test cases continuously during the day or night. In order for test cases to run unattended, they must be able to verify the correct operation of telecommunication services and they must be able to detect errors when they occur. Typically, test cases are designed to accomplish this by dynamically comparing the test case results against predefined expected results. Alternatively, test cases can be programmed to generate test result logs or the like, which can be analyzed at a later time.
In addition, in order for test cases to run unattended, the telecommunication service under test must not require human interaction. For example, telecommunication services such as voice mail systems, automated collect call services and the like, generally require human interaction. Human interaction can be in the form of speech and/or telephone keypad input. As such, testing these types of telecommunication services are conventionally performed manually.
Another difficulty arises when testing telecommunication services that include the use of manual operators. Typically such services involve human operators interacting with customers from manual operator consoles. The very nature of such human interaction makes the testing of such service inherently difficult to automate. Thus, these types of services are also conventionally tested manually. Moreover, today's hardware is increasingly dependent upon and tightly coupled with software that enables many of the features that consumer's demand. As the software and hardware are joined, the complexity of the software components and the difficulty of testing the union of the software and the hardware has increased in complexity.
Former software and hardware development tools included editors, debuggers and a lot of programmer sweat time. With the complexity of modern software and hardware, and the many possible scenarios that must be tested to assure proper system function, it is necessary to replace older, primitive tools with a testing system that is flexible and capable of testing many, diverse permutations of software enabled hardware features.

System, method and article of manufacture for time point validation


A reference signal generating circuit is provided that generates a reference signal corresponding to an input signal for power factor compensation of a power converter. The reference signal generating circuit includes a detector sampling the input signal according to a reference clock to detect and hold the maximum input signal and a phase measuring unit measuring a phase of the sampled input signal based on the sampled input signal and the detected maximum input signal. The circuit also includes a reference signal generating unit configured to generate a reference signal having a specific value in response to the measured phase.

1. Field
The following description relates to a reference signal generation and a power factor compensation technique. The following description also relates to a reference signal generating circuit and a power factor compensation apparatus that measures a phase for an input signal of a power converter, in order to generate a reference signal having a specific amplitude and in order to improve power factor correction.
2. Description of Related Art
A power converter converts inputted power into another, outputted power, such as an outputted power having a different current, voltage or frequency. For example, the power converter receives inputted power to provide outputted power to a load, for example, a LED lamp. Herein, the inputted power may correspond to an alternating current AC power and the outputted power may correspond to a direct current DC power.
A waveform of a current flowing into the load is similar to that of a current of the inputted power. However, a reactive power loss may occur due to a phase difference between a voltage and a current of the inputted power.
In order to decrease the reactive power loss and to improve a power factor correction of the power converter, the phase difference between a voltage and a current of the inputted power may be decreased.
Some power converters perform a full-wave rectification on an inputted alternating current power source to generate an input voltage and sense the input voltage to generate a reference signal. Such power converters compare the reference signal and the current flowing into the load to control a level of the current flowing into the load based on the reference signal. The reference signal is varied according to the input voltage. Accordingly, a level of the current flowing into the load is varied according to the reference signal. Therefore, a frequency and a phase for the current flowing into the load are similar to those of the input voltage. For example, when the input voltage corresponds to a sine wave, the input current waveform becomes similar to a sine wave. As a result, the phase difference between a voltage and a current of the inputted power may be decreased, as discussed above.
However, when such power converters use a resistor element in order to detect the input current, it may be difficult to integrate a control unit for controlling the power converter into the architecture of the power converter due to difficulties of integrating resistors that resist a high input voltage.
FIG. 1 is a waveform diagram illustrating a reference signal that is generated by a power converter. Referring to FIG. 1, the power factor correction circuit approximately measures a single period, such as T1 through T3, to generate a corresponding reference clock RCLK signal. Therefore, the power factor correction circuit generates a sine wave SREF programmed in a digital/analog converter (D/A converter), based on the generated reference clock RCLK.
In the power factor correction circuit, an error of the reference clock RCLK may occur due to an error of single period information, such as T1 through T3. However, a correction for the error in the D/A converter is not performed and a distortion between the input voltage Vin and the sine wave SREF occurs according as the sine wave SREF programmed regardless of how the input signal Vin is generated.

Reference signal generating circuit and method using a sampled input signal and a reference clock signal, and power factor compensation apparatus having the same


A cartridge for containing material in paste form, having a cylindrical container unit, an outlet tip with an outlet passage disposed at one end of the container unit at an angle to its axis, a protective cap encasing the outlet tip, a mounting disposed at the second end of the cylindrical container unit, which is provided for mounting the cartridge in an ejector device, and a piston having a cylindrical circumferential surface and disposed for movement in the longitudinal direction of the cartridge which is provided for sealing off the cartridge interior as well as for dispensing the paste material. In order to attach the cartridge securely to an ejector device and assure a high standard of hygiene, the end of the outlet tip remote from the container unit, at which an outlet orifice is disposed, is at a radial distance from the axis of the container unit that is no more than exactly as great as the radius of the container unit. The mounting is configured as a screw thread and the protective cap as a cylinder closed at one end, whose inside diameter is at least just as great as the outside diameter of the container unit, the protective cap encasing the container unit.

The invention relates to a cartridge for containing material in paste form, having a cylindrical container unit, an outlet tip with an outlet passage at one end of the container at an angle to its axis, a cap protecting the outlet nozzle, a fastening means disposed at the second end of the cylindrical container unit and provided for attaching the cartridge to an ejector device, and having a piston which has a cylindrical outer surface and is disposed for movement lengthwise of the cartridge so as to eject the paste material. The invention furthermore relates to a cap to protect a cartridge and an ejector device for manipulating the cartridge.
Such cartridges and corresponding ejectors are disclosed, for example, in U.S. Pat. No. 4,391,590. These cartridges serve for the dispensing of dental material by the dentist. A filling material for teeth, for example, is loaded into the cartridge. The cartridge is placed in an ejector device whereby the material is forced out of the cartridge with a piston, into a tooth cavity for example. For this purpose the known cartridge has a mounting flange with which it is held in the ejector device. The cartridge itself has an outlet tip which is closed with a cap. The back end of the cartridge is closed by a piston. The mounting of such a cartridge is relatively complicated, because the force required for the ejection of the dental material has to be withstood by the relatively small flange. To insert the cartridge into an ejector device, the cartridge has to be grasped by the dentist or by an assistant, with the result that germs can be transferred to its surface. Since such cartridges are held by their cylindrical barrel, any germs on the ejector device can be transferred directly onto the cartridge, and can pass from there into the patient's mouth.

Cartridge for containing material in paste form


A system is described for transmitting video signals over various communication media using digital signal processing techniques. An embodiment of the system uses an orthogonal frequency division multiplexing (OFDM) modulation process that enables high-speed data communications of Ethernet and/or MPEG or JPEG or H264 compressed or uncompressed digital video. A second embodiment frequency modulates the OFDM modulated signal (FM-OFDM). The first and second embodiments are implemented with a transmit Ethernet interface, an MPEG or JPEG or H264 compressed or uncompressed digital video capture device, and a modem including a modulator and demodulator that provides communication with several other modem devices along communication media such as power lines, wireless (air), cable, or twisted pairs.

The present invention relates to a system for transmitting digital data over a variety of communications media.
Ethernet protocol has seen tremendous growth in the past few years. Video compression techniques such as MPEG, JPEG, H264 are also in larger and larger demand. A wide variety of applications are expected to be based on video compression techniques including: surveillance cameras in grocery stores and parking lots, Internet imaging, IP video, and cameras for underground or underwater exploration. Due to technology limits, Ethernet protocol and compressed digital video communications are currently supported on only a limited number of physical media. New technology advancements proposed herein make possible the use of Ethernet protocol and compressed and uncompressed digital video with a variety of communication media.
One digital signal processing technique suitable for transmitting video over a variety of communications media is called orthogonal frequency division multiplexing (OFDM). OFDM is used in the telecommunications industry with multi-modulated carrier frequency transmission and reception. OFDM can be combined with adaptive coding and modulation techniques, such as 64QAM, 32QAM, 16QAM, QPSK and BPSK modulation. In order to approach channel capacity, a certain signal-to-noise ratio (SNR) is required for each coding and modulation combination to achieve a desired bit error rate (BER) performance. Even higher SNRs are needed if the system uses a larger alphabet size for achieving a higher data rate. Adaptive coding can also be used with OFDM to combat SNR variations. For example, when the signal is heavily attenuated through the channel, the same data can be repeated several times to boost the SNR at the receiver end for a reliable data recovery. However, repeating the data reduces the throughput of the communication system.
Other digital signal processing techniques include spread spectrum, quadrature phase shift keying (QPSK); phase shift keying (PSK); 16, 32 and 64 quadrature amplitude modulation (xxQAM); frequency shift keying (FSK), and frequency offset keying modulation.
In order to achieve desired SNRs for reliable communication and to keep the throughput high, the digital data stream may be frequency modulated before transmission and frequency demodulated before being decoded. Frequency modulating the digital data stream gains 10-20 dB in SNR. Resulting in: (1) significantly longer distance communication without increasing the transmit power level and (2) significantly higher throughput to maintain high speed through the communication media. Suitable communication media includes but is not limited to AC and DC power lines, wireless media, cable, telephone lines, twisted pairs, and coaxial cable. DC power line communications includes the communication over the DC wiring harness of moving vehicles like trucks, buses, SUV's and etc. With the advantage of using frequency modulated digital signal processing, Ethernet protocol and compressed or uncompressed digital video with or without audio from a digital camera, digital camcorder, monitor or TV input can be supported over all the above mentioned media.
Frequency offset (ON/OFF) keying is another digital modulation technique that is being used in the communication industry. Differential frequency offset keying (FOK) can improve the SNR through the communication media. Furthermore multiple FOK modulated carrier frequencies can be used to create frequency division multiplexing (FDM) or OFDM where, instead of using QPSK, BPSK, or 16QAM modulation, FOK modulation can be used for multi modulated carrier frequencies. This can further improve SNR by using the frequency modulated DSP technique, where FOK modulation is used for the carrier frequencies.

Apparatus and method for transmitting digital data over various communication media


A method of modeling a speech recognition system includes decoding a speech signal produced from a training text to produce a sequence of predicted speech units. The training text comprises a sequence of actual speech units that is used with the sequence of predicted speech units to form a confusion model. In further embodiments, the confusion model is used to decode a text to identify an error rate that would be expected if the speech recognition system decoded speech based on the text.

The present invention relates to speech recognition. In particular, the present invention relates to modeling the performance of speech recognition systems.
In speech recognition, an acoustic signal is converted into a sequence of words using an acoustic model and a language model. The acoustic model converts features of the acoustic signal into possible sequences of sub-word speech units such as phones with probabilities. The language model provides probability distributions for various sequences of words that can be formed from the sequences of phones identified by the acoustic model.
Acoustic models are typically trained by having a speaker read from a known text and then crafting the acoustic model so that it predicts the training text from the training speech. Language models are typically trained from large corpora of text by simply identifying the probability of various word sequences in the corpora.
The performance of the resulting speech recognition system is somewhat tied to the training text used to train the acoustic model and the language model. As a result, in certain task domains, the speech recognition system will perform better than in other task domains. In order to determine how a speech recognition system will work in a particular task domain, someone must speak the words that a user is expected to use when performing the task in order to generate acoustic data that can be decoded by the system. Hiring people to generate a sufficient amount of acoustic data to determine the performance of the speech recognition system is expensive and forms a barrier to developing speech enabled computer applications.
In addition, because it is expensive to produce acoustic data, such data has not been generated for the entire corpora used to train the language model. As a result, the language model has typically been trained without examining how the acoustic model will perform on the language model corpora. Thus, it would be beneficial to have a system that allowed a corpus of text to be used in measuring the performance of the combination of an acoustic model and a language model without the need for acoustic data. This would allow for discriminative training of language models in combination with acoustic models.

Method and apparatus for predicting word error rates from text


An exemplary embodiment of a multi-tenant database system is provided. The system includes a multi-tenant database, an entity definition table, and a data processing engine. The database has database objects for multiple tenants, including an existing object for a designated tenant. Each entry in the existing object has a respective entity identifier. The definition table has metadata entries for the database objects, including a metadata entry for the existing object. This metadata entry has a tenant identifier for the designated tenant, an entity name for the existing object, and an old key prefix for the existing object. Each entity identifier of the existing object begins with the old key prefix. The engine performs a data truncation operation on the existing object by updating the metadata entry to replace the old key prefix with a new key prefix. This results in an updated object that is identified by the new key prefix and the tenant identifier.

Modern software development is evolving away from the client-server model toward network-based processing systems that provide access to data and services via the Internet or other networks. In contrast to traditional systems that host networked applications on dedicated server hardware, a "cloud" computing model allows applications to be provided over the network "as a service" supplied by an infrastructure provider. The infrastructure provider typically abstracts the underlying hardware and other resources used to deliver a customer-developed application so that the customer no longer needs to operate and support dedicated server hardware. The cloud computing model can often provide substantial cost savings to the customer over the life of the application because the customer no longer needs to provide dedicated network infrastructure, electrical and temperature controls, physical security and other logistics in support of dedicated server hardware.
Multi-tenant cloud-based architectures have been developed to improve collaboration, integration, and community-based cooperation between customer tenants without sacrificing data security. Generally speaking, multi-tenancy refers to a system wherein a single hardware and software platform simultaneously supports multiple user groups (also referred to as "organizations" or "tenants") from a common data store. The multi-tenant design provides a number of advantages over conventional server virtualization systems. First, the multi-tenant platform operator can often make improvements to the platform based upon collective information from the entire tenant community. Additionally, because all users in the multi-tenant environment execute applications within a common processing space, it is relatively easy to grant or deny access to specific sets of data for any user within the multi-tenant platform, thereby improving collaboration and integration between applications and the data managed by the various applications. The multi-tenant architecture therefore allows convenient and cost effective sharing of similar application features between multiple sets of users.
Certain operations that are common or routinely executed in a traditional database environment may be difficult or impractical to execute in a multi-tenant database architecture. For example, a standard "Truncate" operation cannot be effectively utilized in a multi-tenant database architecture where database objects for different tenants are maintained in a common table. Consequently, it may require a significant amount of time to physically delete a large amount of data from a database object maintained in a multi-tenant database system. For example, it may require hours or days of system time to physically delete a large database object that includes millions of rows of data, due to the nature of the multi-tenant environment, limitations of a database management application, or the like. For various reasons, database users would prefer to have deleted data removed from a database object as quickly as possible. One possible workaround for this scenario is to drop and recreate a custom object. Unfortunately, this workaround is not ideal because the user must rework any associated applications and customizations to refer to the new custom object.

Truncating data associated with objects in a multi-tenant database


In a fuel cell in which an electrode and a separator are stacked together, a rib which is provided on the separator and forms a reaction gas flow path is fixed to an electrode by a liquid sealant, and the porosity of a portion of the electrode which has been impregnated with the liquid sealant is lower than the porosity of another portion of the electrode. In order to store surplus liquid sealant, the separator may also have a liquid sealant storage portion that is depressed in the thickness direction from the top of the rib.

1. Field of the Invention
The invention relates to a fuel cell. More particularly, the invention relates to an improvement in the structure of a fuel cell.
2. Description of the Related Art
A fuel cell (such as a polymer electrolyte fuel cell) is typically made by stacking together a plurality of cells each having an electrolyte sandwiched between separators. These separators are provided with ribs (gas flow path ribs) which form flow paths by dividing the area through which reaction gases (i.e., fuel gas and oxidizing gas) flow. These gas flow path ribs are generally parallel with one another, for example.
Conventionally, when a separator is provided with such ribs, ribs that divide adjacent flow paths where the reaction gas flows in opposite directions are often wider than ribs that divide adjacent flow paths where the reaction gas flows in the same direction (see Japanese Patent Application Publication No. JP-A-2001-76746, for example). This is mainly in order to inhibit the reaction gas from taking a shortcut to an adjacent flow path by seeping past the ribs, a phenomenon referred to as path cutting, and is often used in fuel cells or the like that have so-called serpentine gas flow paths.
However, even with ribs that are structured in the manner described above, it is difficult to sufficiently inhibit path cutting of the reaction gas. When such path cutting occurs and the reaction gas takes a shortcut in the course of its flow, the flow of the gases along their gas flow paths becomes disturbed which reduces the gas stoichiometry in the power generating region, thus reducing power generating performance.


Systems, methods and apparatus are provided for determining corrected population based on a meter drive signal. Systems, methods, and apparatus are additionally provided for determining a stability metric based on a meter drive signal. A method for monitoring a seed application rate of a seed planter includes measuring a rotation of a seed disc of a seed meter, measuring a performance value corresponding to the seed meter, and calculating the population value based on the rotation and the meter performance value.

In recent years, farmers and agronomists have increasingly recognized the importance of population (i.e., the number of seeds planted per acre) in maximizing yield and profit in the cultivation of corn and other crops. Thus there is a need in the art for improved systems and methods for controlling and monitoring application rates, particularly seed planting population.

Application control and monitoring apparatus, systems and methods