A device and a method are provided in which stable tracking control can be carried out even in an arbitrary phase by optically reading pits provided in a disk when information is recorded on and reproduced from the disk with a magnetic head. With respect to difference signals obtained from a main beam signal and sub-beam signals obtained through three-beam type photodetectors, gain correction is executed in variable gain amplifiers, respectively, so that output signals therefrom have same amplitude levels and are different in phase by 90 degrees in a track crossing direction, and thus a tracking error signal is generated by being synthesized from the output signals. Based on the tracking error signal, tracking control is carried out.

1. Field of the Invention
The present invention relates generally to a tracking signal generating device for obtaining a tracking error signal for positioning an optical head or a magnetic head in recording and/or reproducing information with respect to an information recording medium such as a high-density floppy disk, optical disk, or the like and to a magnetic recording/reproducing system carrying out tracking control using the tracking signal generating device.
2. Related Background Art
The intervals between tracks where a series of information is recorded are reduced with the increase in recording density with which information is recorded on a magnetic disk such as a floppy disk. This makes it difficult to position a magnetic head or the like in a direction perpendicular to the tracks with a mechanical precision. Consequently, an optical positioning technique has been required.
For instance, in a high-density floppy disk, tracks formed of tracking pit rows are arranged at an interval of about 20 xcexcm so that a magnetic head can track information tracks arranged at an interval of about 10 xcexcm. In this case, using an optical system with an numerical aperture NA of about 0.04 on a disk side with a wavelength of a light source of 780 nm, a tracking error signal can be obtained. The tracks to be tracked are formed of pit rows whose lengths are 40 to 70 xcexcm. The lengths of the pit rows are determined depending on the radial position so that signals from the tracks obtained at a revolution rate of 720 per minute have a frequency of 20 kHz. A conventional example used for obtaining a tracking signal from such a disk is described with reference to FIG. 15 as follows.
Light emitted from a semiconductor laser 101 as a light source is incident on a diffraction grating 162 provided at a first plane of a diffraction element 160 to generate xc2x11st-order diffracted lights (not shown in the figure). In this case, zero-order light is referred to as a main beam (M) and xc2x11st-order diffracted lights as sub-beams (S1 and S2).
The main beam and the sub-beams pass through a diffraction grating 161 provided at a second plane of the diffraction element 160 and are converged by a lens 104 as a converging means. The main beam and the sub-beams that have become converged lights are focused on a disk 107 as an information recording medium with an aperture being limited so that a desirable numerical aperture (NA) is obtained through an aperture 105.
With reference to FIG. 16, the relationship between the beams and a pit row on the disk is described. There are tracks 204 formed of rows of pits 205 on the disk 107. On the disk 107, a beam row formed of a main beam (M) 201 and two sub-beams (S1 and S2) 202 and 203 is positioned so as to have a predetermined angle xcex80 with respect to a track 204 of the disk 107.
In the figure, l denotes an interval between M and S1 or S2 on the disk 107, Tp indicates an interval between two adjacent tracks 204, and Tpp denotes a radial distance from M to S1 or S2. A tangential direction is a circumferential direction in the disk 107 and a radial direction is a direction of the radius of disk 107.
Returning to FIG. 15, the main beam and the sub-beams reflected from the disk 107 pass through the aperture 105 and the lens 104 again and are diffracted by the diffraction grating 161, and then enter a photodetector 108R or 108L.
The photodetectors 108R and 108L include a plurality of detection regions to receive the main beam and the sub-beams separately, and output signals corresponding to the quantity of received beams. The three beams irradiate locations different in a direction perpendicular to the tracks on the disk 107. Therefore, signals obtained from the three detection regions are different in modulation degree from one another. Through calculation of these signals by a tracking error signal generating device shown in FIG. 17, the relative positional relationship between the track and the beam irradiation locations can be detected.
Next, the following description is directed to the tracking error signal generating device shown in FIG. 17. One sub-beam S1 of the two sub-beams is received by a detection region 301 of the photodetector 108L and a detection region 304 of the photodetector 108R and the respective photodetectors 108L and 108R output currents corresponding to the quantity of the received beams. The currents are converted to a voltage signal by an I-V amplifier 401, which then is output. Similarly, the main beam M is received by a detection region 302 of the photodetector 108L and a detection region 305 of the photodetector 108R, and current signals corresponding to the quantity of the received beams are converted to a voltage signal by an I-V amplifier 402, which then is output. Furthermore, another sub-beam S2 also is received by a detection region 303 of the photodetector 108L and a detection region 306 of the photodetector 108R, and current signals corresponding to the quantity of the received beams are converted to a voltage signal by an I-V amplifier 403, which then is output.
In this case, generally, the three beams M, S1, and S2 generated by the diffraction grating 161 are affected by diffraction efficiency and their quantities received by the photodetectors 108L and 108R are different from one another. Therefore, the I-V amplifiers 401, 402, and 403 have a gain ratio canceling the influence of the diffraction efficiency.
Next, the signals output from the I-V amplifiers 401, 402, and 403 are input into bandpass filters 404, 405, and 406, respectively, and are subjected to bandpass with signals of 20 kHz as a frequency used for the reproduction of a pit row being centered. The signals output from the bandpass filters 404, 405, and 406 are input into detection circuits 407, 408, and 409, respectively. From the signals of 20 kHz, their envelope signals are extracted. The amplitudes of the envelope signals reflect the positional relationships between the track and the beams on the disk 107 and vary accordingly.
The signal output from the detection circuit 407 is indicated as Ss1, the signal output from the detection circuit 408 as Sm, and the signal output from the detection circuit 409 as Ss2.
Further, an amplitude level of the signal Sm (xc2xd of the difference between a maximum value and a minimum value of the signal Sm when an optical beam moves for a distance equal to or more than the interval Tp in the radial direction on the disk 107) is indicated as Lm, amplitude levels of the signals Ss1 and Ss2 as L1 and L2, respectively, a phase of the signal Ss1 with respect to the signal Sm as xcfx861, and a phase of the signal Ss2 with respect to the signal Sm as xcfx862. In this case, the signals Sm, Ss1, Ss2 and the phases xcfx861 and xcfx862 are expressed by
Sm=Lmxc3x97sin xcex8,xe2x80x83xe2x80x83Eq. 1
Ss1=L1xc3x97sin(xcex8xe2x88x92xcfx861),xe2x80x83xe2x80x83Eq. 2
Ss2=L2xc3x97sin(xcex8+xcfx862), andxe2x80x83xe2x80x83Eq. 3
xcfx861=xcfx862=2xcfx80xc3x97Tpp/Tp,xe2x80x83xe2x80x83Eq. 4
wherein xcex8 can be obtained by xcex8=2xcfx80xc3x97Lj/Tp, where Lj denotes a radial distance between the track 204 and the main beam M.
Next, a differential operational circuit 410 receives the signals Ss1 and Sm and outputs a difference signal Sa thereof. In addition, a differential operational circuit 411 receives the signals Sm and Ss2 and outputs a difference signal Sb thereof. These difference signals Sa and Sb are expressed by
Sa=Smxe2x88x92Ss1=Laxc3x97sin(xcex8+xcfx86a) andxe2x80x83xe2x80x83Eq. 5
Sb=Ss2xe2x88x92Sm=Lbxc3x97sin(xcex8+xcfx86b),xe2x80x83xe2x80x83Eq. 6
wherein the amplitude levels La and Lb of the signals Sa and Sb and the phase differences xcfx86a and xcfx86b are expressed by                               tan                                xe2x80x83                              φ                                xe2x80x83                              a                =                                            -              L1                        *            sin                                      xe2x80x83                                    φ                                      xe2x80x83                                    1                                              -              Lm                        +                          L1              *              cos                                            xe2x80x83                                                          φ                                1                                                                        Eq. 7                                La        =                                            Lm              2                        +                          L1              2                        +                          2              *              Lm              *              L1              *              cos                                            xe2x80x83                                          φ                                            xe2x80x83                                          1                                                          Eq. 8                                          tan                                xe2x80x83                              φ                                xe2x80x83                              b                =                                            -              L2                        *            sin                                      xe2x80x83                                                  φ                            2                                            Lm            -                          L2              *              cos                                            xe2x80x83                                                          φ                                2                                                                        Eq. 9                                Lb        =                                            Lm              2                        +                          L2              2                        +                          2              *              Lm              *              L2              *              cos                                            xe2x80x83                                          φ                                            xe2x80x83                                          2                                                          Eq. 10
Then, a signal synthesizing circuit 412 receives the difference signals Sa and Sb and synthesizes a tracking error signal TE. This signal TE is expressed by
TE=xcex1jxc3x97Sa+xcex2jxc3x97Sb,xe2x80x83xe2x80x83Eq. 11
wherein xcex1j and xcex2j are given by
xcex1j=cos xcfx86j andxe2x80x83xe2x80x83Eq. 12
xcex2j=sin xcfx86j,xe2x80x83xe2x80x83Eq. 13
where xcfx86j is defined as
xcfx86j=xe2x88x92xcfx80/4+2xcfx80xc3x97c/Tp.xe2x80x83xe2x80x83Eq. 14
When a distance between a magnetic head 170 and the main beam M on the disk 107 is indicated as Lo-m, Lo-m is expressed by
Lo-m=nxc3x97Tp+c,xe2x80x83xe2x80x83Eq. 15
wherein n denotes an integer, 0 less than c less than Tp holds, and the values of xcex1j and xcex2j are determined by a control circuit 413 so that the tracking error signal TE crosses zero when the magnetic head is positioned on a track.
Practically, the device seeks to position the magnetic head 170 (FIG. 15) in the vicinity of a magnetic track on which predetermined magnetic data have been recorded, and the value of xcfx86j (i.e. the values of xcex1j and xcex2j) is determined through learning so that a maximum amplitude of signals can be obtained or a minimum error ratio can be achieved.
The following description is directed to the reason why the value of xcfx86j must be determined through learning. In a magnetic recording/reproducing system for recording or reproducing information using the magnetic head 170 and detecting the tracking error signal TE using the optical system, the distance Lo-m between the magnetic head and the main beam on the disk 107 must be at least several hundreds of micrometers to several millimeters. In other words, a point P1 where the magnetic head 170 contacts with the disk 107 and a focal point P2 of the main beam M scan different tracks on the disk 107.
In the assembly of the magnetic recording/reproducing system, when the point P1 is positioned exactly on a track of the disk 107, the distance Lo-m is adjusted so that the operating point of the tracking control is positioned in the midpoint of the amplitude of the tracking error signal TE. However, the disk 107 expands and contracts when the temperature or humidity varies and the track pitch Tp varies accordingly. In addition, disks used as the disk 107 may have variations in track pitch Tp, respectively. Therefore, the point P1 deviates from the track to be tracked and the information reproduction characteristic of the magnetic head 170 deteriorates considerably unless the value of xcfx86j (i.e. the values of xcex1j and xcex2j) is determined to correct the tracking error signal TE. In order to avoid such deterioration, the value of xcfx86j is determined through learning.
Values in a table recorded in a memory or the like are used as the values of xcex1j and xcex2j. Based on the tracking error signal TE thus obtained, the tracking control is carried out and the magnetic head 170 tracks an information track to write or readout information.
In a conventional operational circuit or method for obtaining the tracking error signal TE, when the positional relationship between a beam row formed of the main beam M and the two sub-beams S1 and S2 and a track formed of a pit row on the disk deviates from an ideal state, the amplitude level of the tracking error signal TE varies depending on the phase of the tracking error signal to be synthesized. In order to carry out stable tracking control, it is required that the amplitude level of the tracking error signal TE does not vary even when the tracking error signal TE is obtained in an arbitrary phase.
Therefore, the present invention is intended to solve the aforementioned problem, and it is an object of the present invention to provide a tracking signal generating device and method and a magnetic recording/reproducing system, which enable stable tracking control even in an arbitrary phase.
In order to achieve the above-mentioned object, a first tracking signal generating device according to the present invention includes a light source for emitting light, an optical system, photodetectors, position signal generating sections, intermediate signal generating sections, and a signal synthesizing circuit. With the optical system, an information recording medium with a track from which information can be readout optically is irradiated with the light emitted from the light source as at least three optical beams. The photodetectors receive optical beams reflected from the information recording medium. The position signal generating sections output three position signals Sm, Ss1, and Ss2 corresponding to a positional relationship between the three optical beams and the track from signals obtained corresponding to the quantity of the optical beams entering the photodetectors. The intermediate signal generating sections receive the three position signals Sm, Ss1, and Ss2, calculate differences between Sm and Ss1 and between Sm and Ss2 with the position signal Sm being taken as a reference, execute calculation for correction, and generate two intermediate signals Sa and Sb. The signal synthesizing circuit synthesizes a zero-crossing tracking signal in an arbitrary phase with respect to the track from the intermediate signals Sa and Sb. The intermediate signal generating sections execute the correction so that the intermediate signals Sa and Sb have same amplitude levels and are different in phase by xcfx80/2 rad in a track crossing direction, and output them.
In the tracking signal generating device, preferably the signal synthesizing circuit multiplies the two intermediate signals Sa and Sb input thereinto by coefficients xcex1 and xcex2 given by
xcex1=Cxc2x7sin xcfx86 and
xcex2=Cxc2x7cos xcfx86
or
xcex1=Cxc2x7cos xcfx86 and
xe2x80x83xcex2=Cxc2x7sin xcfx86,
where C and xcfx86 are constants, and adds them.
In order to achieve the above-mentioned object, a second tracking signal generating device according to the present invention includes a light source for emitting light, an optical system, photodetectors, position signal generating sections, a first variable gain amplifier, a second variable gain amplifier, a third variable gain amplifier, a fourth variable gain amplifier, a first differential operational circuit, a second differential operational circuit, and a signal synthesizing circuit. With the optical system, an information recording medium with a track from which information can be readout optically is irradiated with the light emitted from the light source as at least three optical beams. The photodetectors receive optical beams reflected from the information recording medium. The position signal generating sections output three position signals Sm, Ss1, and Ss2 corresponding to a positional relationship between the three optical beams and the track from signals obtained corresponding to the quantity of the optical beams entering the photodetectors. The first variable gain amplifier has a coefficient Fm1, receives the position signal Sm, and outputs a signal Fm1xc2x7Sm. The second variable gain amplifier has a coefficient Fm2, receives the position signal Sm, and outputs a signal Fm2xc2x7Sm. The third variable gain amplifier has a coefficient F1, receives the position signal Ss1, and outputs a signal F1xc2x7Ss1. The fourth variable gain amplifier has a coefficient F2, receives the position signal Ss2, and outputs a signal F2xc2x7Ss2. The first differential operational circuit receives the signals Fm1xc2x7Sm and F1xc2x7Ss1 output from the first and third variable gain amplifiers and obtains a difference signal Sa3 of the signals Fm1xc2x7Sm and F1xc2x7Ss1. The second differential operational circuit receives the signals Fm2xc2x7Sm and F2xc2x7Ss2 output from the second and fourth variable gain amplifiers and obtains a difference signal Sb3 of the signals Fm2xc2x7Sm and F2xc2x7Ss2. The signal synthesizing circuit multiplies the difference signals Sa3 and Sb3 from the first and second differential operational circuits by predetermined coefficients and adds them, which is output as a tracking signal. The coefficients Fm1, Fm2, F1, and F2 are determined with respect to the first to fourth variable gain amplifiers so that the difference signals Sa3 and Sb3 have the same amplitude level and are different in phase by xcfx80/2 rad in a track crossing direction.
In the second tracking signal generating device, preferably the respective coefficients Fm1, Fm2, F1, and F2 of the first to fourth variable gain amplifiers satisfy
Fm1/F1=L1xc3x97(cos xcfx861+sin xcfx861)/Lm,
Fm2/F2=L2xc3x97(cos xcfx862+sin xcfx862)/Lm, and
F1/F2=L2xc3x97|sin xcfx862|/(L1xc3x97|sin xcfx861|),
wherein xcfx861 denotes a phase difference between the position signals Sm and Ss1, xcfx862 a phase difference between the position signals Sm and Ss2, Lm an amplitude of the position signal Sm, L1 an amplitude of the position signal Ss1, and L2 an amplitude of the position signal Ss2.
In the second tracking signal generating device, preferably the signal synthesizing circuit multiplies the two difference signals Sa3 and Sb3 input thereinto by coefficients xcex1 and xcex2 given by
xcex1=Cxc2x7sin xcfx86 and
xcex2=Cxc2x7cos xcfx86
or
xcex1=Cxc2x7cos xcfx86 and
xcex2=Cxc2x7sin xcfx86,
where C and xcfx86 are constants, and adds them.
In order to achieve the above-mentioned object, a third tracking signal generating device according to the present invention includes a light source for emitting light, an optical system, photodetectors, position signal generating sections, a first differential operational circuit, a second differential operational circuit, and a signal synthesizing circuit. With the optical system, an information recording medium with a track from which information can be readout optically is irradiated with the light emitted from the light source as at least three optical beams. The photodetectors receive optical beams reflected from the information recording medium. The position signal generating sections output three position signals Sm, Ss1, and Ss2 corresponding to a positional relationship between the three optical beams and the track from signals obtained corresponding to the quantity of the optical beams entering the photodetectors. The first differential operational circuit receives the position signals Sm and Ss1 and outputs a difference signal Sa thereof. The second differential operational circuit receives the position signals Sm and Ss2 and outputs a difference signal Sb thereof. The signal synthesizing circuit multiplies the difference signals Sa and Sb output from the first and second differential operational circuits, respectively, by predetermined coefficients xcex1 and xcex2 and adds them, which is output as a tracking signal. The coefficients xcex1 and xcex2 are given by
xe2x80x83xcex1=(Cxc2x7cos xcfx86)/La and
xcex2=(Cxc2x7sin xcfx86)/Lb
or
xcex1=(Cxc2x7sin xcfx86)/La and
xcex2=(Cxc2x7cos xcfx86)/Lb,
wherein La and Lb denote amplitudes of the difference signals Sa and Sb, respectively, and C and xcfx86 are constants.
In order to achieve the above-mentioned object, a fourth tracking signal generating device according to the present invention includes a light source for emitting light, an optical system, photodetectors, position signal generating sections, a first differential operational circuit, a second differential operational circuit, a signal synthesizing circuit, and a variable gain amplifier. With the optical system, an information recording medium with a track from which information can be readout optically is irradiated with the light emitted from the light source as at least three optical beams. The photodetectors receive optical beams reflected from the information recording medium. The position signal generating sections output three position signals Sm, Ss1, and Ss2 corresponding to a positional relationship between the three optical beams and the track from signals obtained corresponding to the quantity of the optical beams entering the photodetectors. The first differential operational circuit receives the position signals Sm and Ss1 and outputs a difference signal Sa thereof. The second differential operational circuit receives the position signals Sm and Ss2 and outputs a difference signal Sb thereof. The signal synthesizing circuit multiplies the difference signals Sa and Sb output from the first and second differential operational circuits, respectively, by predetermined coefficients and adds them. The variable gain amplifier receives a signal output from the signal synthesizing circuit and multiplies it by a suitable coefficient, which is output as a tracking signal. In the variable gain amplifier, the suitable coefficient is determined so that the signal input into the variable gain amplifier has a predetermined amplitude level during track crossing.
In order to achieve the above-mentioned object, a first tracking signal generating method according to the present invention is carried out by irradiating an information recording medium with a track from which information can be readout optically with light emitted from a light source as at least three optical beams and receiving optical beams reflected from the information recording medium by photodetectors. The first tracking signal generating method includes: generating three position signals Sm, Ss1, and Ss2 corresponding to a positional relationship between the three optical beams and the track from signals obtained corresponding to the quantity of the optical beams entering the photodetectors; receiving the three position signals Sm, Ss1, and Ss2, calculating differences between Sm and Ss1 and between Sm and Ss2 with the position signal Sm being taken as a reference, executing calculation for correction, and generating two intermediate signals Sa and Sb so that they are different in phase by xcfx80/2 rad in a track crossing direction and have same amplitude levels; and synthesizing a zero-crossing tracking signal in an arbitrary phase with respect to the track from the intermediate signals Sa and Sb.
In the first tracking signal generating method, preferably the synthesizing of the zero-crossing tracking signal is executed by multiplying the two intermediate signals Sa and Sb by coefficients xcex1 and xcex2 given by
xcex1=Cxc2x7sin xcfx86 and
xcex2=Cxc2x7cos xcfx86
or
xcex1=Cxc2x7cos xcfx86 and
xcex2=Cxc2x7sin xcfx86,
where C and xcfx86 are constants, and adding them.
In order to achieve the above-mentioned object, a second tracking signal generating method according to the present invention is carried out by irradiating an information recording medium with a track from which information can be readout optically with light emitted from a light source as at least three optical beams and receiving optical beams reflected from the information recording medium by photodetectors. The second tracking signal generating method includes: generating three position signals Sm, Ss1, and Ss2 corresponding to a positional relationship between the three optical beams and the track from signals obtained corresponding to the quantity of the optical beams entering the photodetectors; multiplying the position signal Sm by a coefficient Fm1 to generate a signal Fm1xc2x7Sm; multiplying the position signal Sm by a coefficient Fm2 to generate a signal Fm2xc2x7Sm; multiplying the position signal Ss1 by a coefficient F1 to generate a signal F1xc2x7Ss1; multiplying the position signal Ss2 by a coefficient F2 to generate a signal F2xc2x7Ss2; calculating a difference signal Sa3 of the signals Fm1xc2x7Sm and F1xc2x7Ss1; calculating a difference signal Sb3 of the signals Fm2xc2x7Sm and F2xc2x7Ss2; and multiplying the difference signals Sa3 and Sb3 by predetermined coefficients and adding them, thus synthesizing a tracking signal. The coefficients Fm1, Fm2, F1, and F2 are determined so that the difference signals Sa3 and Sb3 have constant amplitude levels and are different in phase by xcfx80/2 rad in a track crossing direction.
In the second tracking signal generating method, preferably the coefficients Fm1, Fm2, F1, and F2 satisfy
Fm1/F1=L1xc3x97(cos xcfx861+sin xcfx861)/Lm,
Fm2/F2=L2xc3x97(cos xcfx862+sin xcfx862)/Lm, and
F1/F2=L2xc3x97|sin xcfx862|/(L1xc3x97|sin xcfx861|),
wherein xcfx861 denotes a phase difference between the position signals Sm and Ss1, xcfx862 a phase difference between the position signals Sm and Ss2, and Lm, L1, and L2 amplitudes of the position signals Sm, Ss1, and Ss2, respectively.
In the second tracking signal generating method, preferably the synthesizing of the tracking signal is executed by multiplying the two difference signals Sa3 and Sb3 by coefficients xcex1 and xcex2 given by
xcex1=Cxc2x7sin xcfx86 and
xcex2=Cxc2x7cos xcfx86
or
xcex1=Cxc2x7cos xcfx86 and
xcex2=Cxc2x7sin xcfx86,
where C and xcfx86 are constants, and adding them.
In order to achieve the above-mentioned object, a first magnetic recording/reproducing system according to the present invention includes a magnetic head, a light source for emitting light, an optical system, photodetectors, position signal generating sections, intermediate signal generating sections, and a signal synthesizing circuit. The magnetic head records or reproduces information with respect to an information recording medium with a track from which information can be readout optically. With the optical system, the information recording medium is irradiated with the light emitted from the light source as at least three optical beams. The photodetectors receive optical beams reflected from the information recording medium. The position signal generating sections output three position signals Sm, Ss1, and Ss2 corresponding to a positional relationship between the three optical beams and the track from signals obtained corresponding to the quantity of the optical beams entering the photodetectors. The intermediate signal generating sections receive the three position signals Sm, Ss1, and Ss2, calculate differences between Sm and Ss1 and between Sm and Ss2 with the position signal Sm being taken as a reference, execute calculation for correction, and generate two intermediate signals Sa and Sb. The signal synthesizing circuit synthesizes a zero-crossing tracking signal in an arbitrary phase with respect to the track from the intermediate signals Sa and Sb. The intermediate signal generating sections execute the correction so that the intermediate signals Sa and Sb have same amplitude levels and are different in phase by xcfx80/2 rad in a track crossing direction, and output them. Tracking control is carried out according to the tracking signal output from the signal synthesizing circuit.
In the first magnetic recording/reproducing system, preferably the signal synthesizing circuit multiplies the two intermediate signals Sa and Sb input thereinto by coefficients xcex1 and xcex2 given by
xcex1=Cxc2x7sin xcfx86 and
xcex2=Cxc2x7cos xcfx86
or
xcex1=Cxc2x7cos xcfx86 and
xcex2=Cxc2x7sin xcfx86,
where C and xcfx86 are constants, and adds them.
In order to achieve the above-mentioned object, a second magnetic recording/reproducing system according to the present invention includes a magnetic head, a light source for emitting light, an optical system, photodetectors, position signal generating sections, a first variable gain amplifier, a second variable gain amplifier, a third variable gain amplifier, a fourth variable gain amplifier, a first differential operational circuit, a second differential operational circuit, and a signal synthesizing circuit. The magnetic head records or reproduces information with respect to an information recording medium with a track from which information can be readout optically. With the optical system, the information recording medium is irradiated with the light emitted from the light source as at least three optical beams. The photodetectors receive optical beams reflected from the information recording medium. The position signal generating sections output three position signals Sm, Ss1, and Ss2 corresponding to a positional relationship between the three optical beams and the track from signals obtained corresponding to the quantity of the optical beams entering the photodetectors. The first variable gain amplifier has a coefficient Fm1, receives the position signal Sm, and outputs a signal Fm1xc2x7Sm. The second variable gain amplifier has a coefficient Fm2, receives the position signal Sm, and outputs a signal Fm2xc2x7Sm. The third variable gain amplifier has a coefficient F1, receives the position signal Ss1, and outputs a signal F1xc2x7Ss1. The fourth variable gain amplifier has a coefficient F2, receives the position signal Ss2, and outputs a signal F2xc2x7Ss2. The first differential operational circuit receives the signals Fm1xc2x7Sm and F1xc2x7Ss1 output from the first and third variable gain amplifiers and obtains a difference signal Sa3 of the signals Fm1xc2x7Sm and F1xc2x7Ss1. The second differential operational circuit receives the signals Fm2xc2x7Sm and F2xc2x7Ss2 output from the second and fourth variable gain amplifiers and obtains a difference signal Sb3 of the signals Fm2xc2x7Sm and F2xc2x7Ss2. The signal synthesizing circuit multiplies the difference signals Sa3 and Sb3 from the first and second differential operational circuits by predetermined coefficients and adds them, which is output as a tracking signal. The coefficients Fm1, Fm2, F1, and F2 are determined with respect to the first to fourth variable gain amplifiers so that the difference signals Sa3 and Sb3 have the same amplitude level and are different in phase by xcfx80/2 rad in a track crossing direction. Tracking control is carried out according to the tracking signal output from the signal synthesizing circuit.
In the second magnetic recording/reproducing system, preferably the respective coefficients Fm1, Fm2, F1, and F2 of the first to fourth variable gain amplifiers satisfy
Fm1/F1=L1xc3x97(cos xcfx861+sin xcfx861)/Lm,
Fm2/F2=L2xc3x97(cos xcfx862+sin xcfx862)/Lm, and
F1/F2=L2xc3x97|sin xcfx862|/(L1xc3x97|sin xcfx861|),
wherein xcfx861 denotes a phase difference between the position signals Sm and Ss1, xcfx862 a phase difference between the position signals Sm and Ss2, and Lm, L1, and L2 amplitudes of the position signals Sm, Ss1, and Ss2, respectively.
In the second magnetic recording/reproducing system, preferably the signal synthesizing circuit multiplies the two difference signals Sa3 and Sb3 input thereinto by coefficients xcex1 and xcex2 given by
xcex1=Cxc2x7sin xcfx86 and
xcex2=Cxc2x7cos xcfx86
or
xcex1=Cxc2x7cos xcfx86 and
xcex2=Cxc2x7sin xcfx86,
where C and xcfx86 are constants, and adds them.
In order to achieve the above-mentioned object, a third magnetic recording/reproducing system according to the present invention includes a magnetic head, a light source for emitting light, an optical system, photodetectors, position signal generating sections, a first differential operational circuit, a second differential operational circuit, and a signal synthesizing circuit. The magnetic head records or reproduces information with respect to an information recording medium with a track from which information can be readout optically. With the optical system, the information recording medium is irradiated with the light emitted from the light source as at least three optical beams. The photodetectors receive optical beams reflected from the information recording medium. The position signal generating sections output three position signals Sm, Ss1, and Ss2 corresponding to a positional relationship between the three optical beams and the track from signals obtained corresponding to the quantity of the optical beams entering the photodetectors. The first differential operational circuit receives the position signals Sm and Ss1 and outputs a difference signal Sa thereof. The second differential operational circuit receives the position signals Sm and Ss2 and outputs a difference signal Sb thereof. The signal synthesizing circuit multiplies the difference signals Sa and Sb output from the first and second differential operational circuits, respectively, by predetermined coefficients xcex1 and xcex2 and adds them, which is output as a tracking signal. The coefficients xcex1 and xcex2 are given by
xcex1=(Cxc2x7cos xcfx86)/La and
xcex2=(Cxc2x7sin xcfx86)/Lb
or
xcex1=(Cxc2x7sin xcfx86)/La and
xcex2=(Cxc2x7cos xcfx86)/Lb,
wherein La and Lb denote amplitudes of the difference signals Sa and Sb, respectively, and C and xcfx86 are constants. Tracking control is carried out according to the tracking signal output from the signal synthesizing circuit.
In order to achieve the above-mentioned object, a fourth magnetic recording/reproducing system according to the present invention includes a magnetic head, a light source for emitting light, an optical system, photodetectors, position signal generating sections, a first differential operational circuit, a second differential operational circuit, a signal synthesizing circuit, and a variable gain amplifier. The magnetic head records or reproduces information with respect to an information recording medium with a track from which information can be readout optically. With the optical system, the information recording medium is irradiated with the light emitted from the light source as at least three optical beams. The photodetectors receive optical beams reflected from the information recording medium. The position signal generating sections output three position signals Sm, Ss1, and Ss2 corresponding to a positional relationship between the three optical beams and the track from signals obtained corresponding to the quantity of the optical beams entering the photodetectors. The first differential operational circuit receives the position signals Sm and Ss1 and outputs a difference signal Sa thereof. The second differential operational circuit receives the position signals Sm and Ss2 and outputs a difference signal Sb thereof. The signal synthesizing circuit multiplies the difference signals Sa and Sb output from the first and second differential operational circuits, respectively, by predetermined coefficients and adds them. The variable gain amplifier receives a signal output from the signal synthesizing circuit and multiplies it by a suitable coefficient, which is output as a tracking signal. In the variable gain amplifier, the suitable coefficient is determined so that the signal input into the variable gain amplifier has a predetermined amplitude level during track crossing. Tracking control is carried out according to the tracking signal output from the variable gain amplifier.
According to the above-mentioned configurations, even when the three optical beams are not aligned on a straight line, an ideal tracking error signal with a constant amplitude level can be obtained and the variation in gain of tracking servo can be suppressed to 0 dB, thus achieving stable tracking control. As a result, signals can be readout with a low error ratio.
Since the shift of the three beams from the straight line is acceptable, high precision alignment of the optical system is not required, thus reducing the cost of the optical system. In addition, since variations in the alignment are acceptable, the degree of freedom in design of the optical system is increased.
Further, even when the angle formed between the track and the beam row formed of three optical beams is different from an ideal angle, a tracking error signal with a constant amplitude is obtained. Therefore, it is not required to adjust the angle formed between the beam row and the track, thus reducing the manufacturing cost of the magnetic recording/reproducing system using this tracking signal generating device.
In addition to the case where the angle formed between the beam row and the track is different from an ideal angle xcex80, even in a case where the amplitude levels of the signals output from the photodetectors vary, a tracking error signal with a constant amplitude can be obtained. Therefore, adjustment of not only the angle formed between the beam row and the track but also the amplitude levels becomes unnecessary, thus reducing the manufacturing cost of the magnetic recording/reproducing system using this tracking signal generating device.

Tracking signal generating device and method, and magnetic recording/reproducing system

Matsushita Electric Industrial Co., Ltd.


A vestigial sideband (VSB) modulation transmission system and a method for encoding an input signal in the system are disclosed. According to the present invention, the VSB transmission system includes a convolutional encoder for encoding an input signal, a trellis-coded modulation (TCM) encoder for encoding the convolutionally encoded signal, and a signal mapper mapping the trellis-coded signal to generate a corresponding output signal. Different types of the convolutional encoders are explored, and the experimental results showing the performances of the VSB systems incorporating each type of encoders reveals that a reliable data transmission can be achieved even at a lower input signal to noise ratio when a convolutional encoder is used as an error-correcting encoder in a VSB system.

1. Field of the Invention
The present invention relates to a digital communication system, and more particularly, to a vestigial sideband (VSB) modulation transmission system including a TCM (Trellis-Coded Modulation) encoder and an additional ½ rate convolutional encoder having a superior state transition property when connected to the TCM encoder in the system.
2. Background of the Related Art
The TCM coded 8-VSB modulation transmission system has been selected as a standard in 1995 for the U.S. digital terrestrial television broadcasting, and the actual broadcasting incorporating the system has started since the second half of the year 1998.
In general, a digital communication system performs error correcting processes to correct the errors occurred at the communication channels. The total amount of the transmitting data is increased by such error correcting coding processes since it creates additional redundancy bits added to the information bits. Therefore, the required bandwidth is usually increased when using an identical modulation technique. Trellis-coded modulation (TCM) combines multilevel modulation and coding to achieve coding gain without bandwidth expansion. Also an improved signal to noise ratio can be achieved by using the trellis-coded modulation (TCM) technique.
FIG. 1A and FIG. 1B illustrate a typical TCM encoder used in a typical ATSC 8-VSB system and corresponding set partitions used by the TCM encoder. According to the FIG. 1A, an input bit d0 is output as c1 and c0 after trellis-coded modulation, and then a subset is selected among (−7,1), (−5,3), (−3,5), and (−1,7). Thereafter, an input bit d1 selects a signal within the selected subset. In other words, when d1 and d0 are inputted, one of eight signals (−7,−5,−3,−1,1,3,5,7) is selected by c2, c1, and c0 generated by the TCM encoder. d1 and d0 are called an uncoded bit and a coded bit, respectively.
FIG. 1B illustrates the set partitions used by the TCM encoder used in the ATSC 8-VSB system. Eight signal levels are divided into four subsets, each of which including two signal levels. Two signals are assigned to each subset such that the signal levels of each subset are as far as possible from each other as shown in FIG. 1B.


Provided are recombinant antibodies comprising one or more peptides fused to the C-terminus of the light chain constant region. Recombinant immunocytokines comprising a cytokine fused to the C-terminus of the light chain constant region are described and shown to be surprisingly active.

Immunocytokines (antibody-cytokine fusion proteins) were first reported in the literature in the early 1990s and consisted of whole antibody fusions with cytokines such as lymphotoxin (TNF-β) or interleukin 2 (IL2). Subsequent studies in GD2-expressing tumor models in mice indicated that the ch14.18 antibody and ch14.18-IL2 immunocytokine both had anti-tumor activity but that the immunocytokine was far more potent than the antibody, even when combined with free IL2. Sabzevari H et al. (1994) Proc Natl Acad Sci USA 91:9626-30; Pancook J D et al. (1996) Cancer Immunol Immunother 42:88-92; Becker J C et al. (1996) Proc Natl Acad Sci USA 93:2702-7. In addition, immune-competent mice treated with the immunocytokine, but not the antibody plus IL2, developed an adaptive immune response dependent on CD8+ T cells that prevented subsequent tumor challenge. Becker J C et al. (1996) J Exp Med 183:2361-6; Becker J C et al. (1996) Proc Natl Acad Sci USA 93:7826-31. Thus, the targeting of IL2 to the tumor microenvironment induces an anti-tumor vaccine effect that is not possible with the antibody, either alone or together with the free cytokine. A related humanized immunocytokine, hu14.18-IL2, has recently achieved clinical proof of concept in relapsed neuroblastoma as monotherapy where it induced a significant number of complete responses in patients with no other treatment options. Many publications describe the ability of this molecule to activate several components of the immune system to kill tumor cells and to evoke a long lasting CD8 T cell memory response that resists subsequent tumor challenge.

Light chain immunoglobulin fusion proteins and methods of use thereof


A perforating gun, adapted to be disposed in a deviated borehole, includes an intra-gun swivel located between a first plurality of charges and a second plurality of charges of the perforating gun. The swivel includes a first housing, a second housing, and thrust and radial bearings disposed between the surfaces of the first and second housing for allowing the first housing to rotate with respect to the second housing and therefore the first plurality of charges to rotate with respect to the second plurality of charges of the perforating gun.

The subject matter of the present invention relates to a swivel disposed in a perforating gun for enabling opposite parts of the perforating gun to independently swivel about an axis.
Perforating guns are sometimes disposed in deviated boreholes. When disposed in the deviated borehole, the perforating gun is rotated in order to direct the charges in a selected direction into the formation. Normally, a swivel located in the tubing string above the firing head of the perforating gun enables the perforating gun to rotate. However, since the swivel is located in the tubing string above the firing head of the gun, certain problems are created: (1) alignment error builds up in oriented guns, (2) torque builds up along the gun string, and (3) the swivel interferes with certain components above the gun string, such as hydraulic flow tubes, drop bars and slickline tools.


A system directed to analyzing technology resources in terms of many different factors to determine a need to alter/adjust the technology resource. Specifically, the present invention correlates data associated with (i) a level of performance of a technology resource relative to technology resource users, (ii) results of the technology resource relative to facility users, and (iii) a qualitative value associated with the technology resource to determine a technology resource metric that indicates a need to alter/adjust the technology resource and trigger one or more actions associated with altering/adjusting the technology resource. In specific embodiments, the technology resource metric of one facility is compared to one or a plurality of other facilities to determine a technology resource index for the technology resource.

Facilities have need to alter technology resources, such as increase or decrease hardware, middleware, software or the like. Such alteration to technology resources may have an effect on the overall volume of resources generated by the facility. However, it is often difficult to determine when and the degree of technology resource alteration without properly assessing determinative factors that drive technology resource alteration.
For example, while level of performance of the technology resource relative to the technology resource users and a qualitative value of the technology resources may be determinative of altering resources, such determinative factors may not provide for a comprehensive assessment as to when technology resource alteration should occur and the degree of the technology resource alteration.
Moreover, in determining when and to what degree a technology resource should be altered it may be beneficial to compare the determinative factors of one facility to the same determinative factors of one or more other similar facilities in order to assess or otherwise predict the overall volume of resources that are expected to be generated based on an increase in the qualitative value and or a change in other determinative factors (e.g., level of performance, results and the like).
Therefore, a need exists to provide for a system that analyzes technology resources in terms of many different determinative factors to determine a need to alter/adjust the technology resource. Specifically, a need exists to analyze the technology resource so as to insure that altering/adjusting the technology resource maximizes the qualitative value of the technology resource. In addition, a need exists to compare the same technology resource alteration determinative factors from one facility to one or more similar facilities to predict the overall volume of resources that are expected to be generated based on an increase in the qualitative value and or a change in other determinative factors (e.g., level of performance, results and the like).

System for resource utilization analysis and resource alteration


Barcode decoding bypassing binarization is provided which relies on deformable templates to makes use of all the gray level information of each pixel in the barcode image. Parameterization of the deformable templates allow for efficiently performing maximum likelihood estimation independently on each barcode digit and enforcing spatial coherence across the barcode digits.

Today, virtually every item on the market is labeled with at least one form of barcode, generally a flavor of either the EAN or the UPC standards. The success of barcode technology for identification, tracking, and inventory derives from its ability to encode information in a compact fashion with low associated cost.
Barcode reading via dedicated scanners is a mature technology. Commercial laser-based hand-held barcode scanners achieve robust reading with a reasonable price tag. Recently, there has been growing interest in accessing barcodes also with regular cellphones, without the need for a dedicated device. Indeed, a number of cellphone applications (apps) have appeared that provide access via barcode reading to the full characteristics of and user reviews for a product found at a store.
Unfortunately, images taken by cellphone cameras are often of low quality. Many cellphone cameras on the market are equipped with low-grade lenses, often lacking focusing capability, which often produce blurred images. Few cellphones have a flash and, therefore, motion blur and noise can be expected with low ambient light. All of these factors, possibly combined with low image resolution, make barcode reading difficult in certain situations. Indeed, all existing image-based barcode readers have limited performance when it comes to images taken in difficult light conditions, or when the camera is not close enough to the barcode. To improve accuracy, barcode reading apps usually prompt the user to precisely position the camera to ensure that the barcode covers as much of the frame as possible. This operation can be somewhat bothersome, as it requires a certain amount of interaction with the user, who needs to frame the barcode correctly using the viewfinder.
This invention presents new techniques for barcode reading advancing the art and overcoming at least some of the current problems or shortcomings with existing barcode reading techniques.

The Regents of the University of California


A motor-driving circuit includes: a plurality of output transistors; a first-comparator circuit to compare a voltage of each phase of driving coils of a plurality of phases in a motor, with a neutral-point voltage; a position-detecting circuit to detect a rotor position of the motor based on a comparison result of the first-comparator circuit; a switching-control circuit to supply switching signals to the plurality of output transistors according to the rotor position; and a current-limiting circuit to limit the driving currents to a first-current value so that the motor rotates at a target-rotation speed when the current-limiting circuit determines that the motor is rotating at a speed higher than or equal to a predetermined-reference-rotation speed, and limit the driving currents to a second-current value smaller than the first-current value when the current-limiting circuit determines that the motor is not rotating at the speed higher than or equal to the predetermined-reference-rotation speed.

1. Field of the Invention
The present invention relates to a motor driving circuit.
2. Description of the Related Art
A sensorless method, which does not require a position detecting device such as a Hall element, is known as a driving method for a brushless DC motor which includes driving coils of a plurality of phases (e.g., three phases). In the sensorless method, a counter electromotive force which is generated in each of the driving coils is used, and a voltage of each of the driving coils of the phases is compared with a voltage of a neutral point, so that a position of a rotor (rotator) can be detected.
In addition to a PWM (Pulse Width Modulation) method, a PAM (Pulse Amplitude Modulation) method disclosed in Japanese Laid-Open Patent Publication Nos. 2000-350490, 2002-142484, and 2008-259340 is known as a control method of output transistors that supply driving currents to the driving coils, for example. According to the PAM method, a pulse-amplitude-modulated switching signal is supplied to the output transistors.
FIG. 4 depicts an example of a configuration of a common motor driving circuit configured to drive a sensorless three-phase motor by the PAM method.
In a motor driving circuit lb depicted in FIG. 4, a comparator circuit 21 compares voltages U, V, and W of the phases of driving coils 61 to 63 with a voltage COM of a neutral point. A position detecting circuit 11 detects the position of a rotor of a motor 6 based on a comparison result signal CMP. A switching control circuit 12 generates switching signals S41 to S43 and S51 to S53, which are pulse-amplitude-modulated according to a rotor position signal RP, and supplies the switching signals to output transistors 41 to 43 and 51 to 53, respectively. The output transistors supply driving currents to the driving coils 61 to 63, and the current value of the driving currents is detected as a voltage RF.
In the motor driving circuit 1b, a comparator circuit 14 compares the voltage RF with a voltage V1, and outputs a current limit signal LMT. The switching control circuit 12 limits the amplitude of each of the switching signals according to the current limit signal LMT, and limits the driving currents to a predetermined current value. Therefore, the comparator circuit 14 functions as a current limiting circuit that limits the driving currents, so that the motor driving circuit 1b can rotate the motor 6 at a target rotation speed.
In this manner, the sensorless three-phase motor can be driven in the PAM method and can be rotated at the target rotation speed.
The sensorless motor driving circuit is not able to detect the position of the rotor at the time of startup. Therefore, the switching control circuit generates predetermined switching signals so that predetermined startup currents are supplied as the driving currents. When the motor starts to be rotated by the startup currents, the position of the rotor can be detected, and therefore, the switching control circuit generates the switching signal corresponding to the position of the rotor.
However, when the target rotation speed of the motor is set at a high speed, great startup currents are supplied to the driving coils, and therefore, the motor may start to rotate at a speed faster than a speed of the switching timings of the switching signals. Therefore, the motor may lose its synchronization or may rotate in the reverse direction at the time of startup.


A computer-implemented method for determining an origin of a target source code for a computer program or a part thereof. The method involves: Searching a plurality of software archives from different sources in a global computer network to find occurrences of the target source code among code files in said software archives. For every found occurrence of the target source code, the method further involves collecting key information about the matching source code files and, from the key information collected a frequency map is built that contains, for each keyword found in the key information, a keyword count value being indicative of the number of times the keyword occurs in the key information. The method may further involves applying a scoring scheme to the matching source code files based on the built frequency map (310), determining a highest score (Vmax) among the matching source code files after the scoring scheme has been applied, and determining the origin of the target source code as the matching source code file having the highest score.

Computer systems are used virtually everywhere in modern society. As is well known, a general computer system comprises at least one processing device which is configured to execute at least one computer program being defined by at least one source code. The source code defines computer program code instructions, that may be run by the processing device to perform certain intended functionality.
Our daily lives strongly depend on computer systems being operationally stable in the sense that they must function flawlessly (i.e., perform the intended functionality without malfunctions) while remaining operational for long periods of time without interruptions. Since the source code in effect controls the behavior of the computer system, it is of paramount importance that it contains the correct computer program code instructions. With a massive code quantity in global software archives together with the open-source model for open collaboration between projects, it is becoming increasingly difficult to confirm the true origin of the code.
Software vulnerabilities and toxic code snippets are being discovered and recorded, both constantly and massively, in global software archives. When a vulnerability is found in an application or a software library, the authors of the code are typically responsible for having well-defined processes to share the relevant information to anyone importing and operating on this code. This information needs to be shared immediately, since it may affect critical security flaws of the code. If a code snippet has been imported from a third party source, this source is not necessarily obliged to share the relevant information, and is much less likely to have a well-defined process for communicating information to code importers. Additionally, outdated and license-violating online code clones are much less likely to be communicated.
Hence, as the validity of the author or organization behind the code in operation may not be credible, operational stability may not be ensured for an operator, host or user of a computer system importing this code.
It may, however, be far from trivial for the operator, host or user to correctly monitor, audit or validate the origins of imported files due to a potentially massive project with a large amount of code contributors. If the origin of the code in a program is unknown, security of the program can't be guaranteed.
In light of the observations above, the present inventor has realized that there is room for improvements when it comes to technical provisions for assessing operational stability of computer systems.

Determining an origin of a target source code for a computer program or a part thereof


The present invention includes a molten metal pump and associated components that enable gas to be released into a stream of molten metal. The gas may be released into the molten metal stream (preferably into the bottom of the stream) flowing through a passage. Such a stream may be within the pump discharge and/or within a metal-transfer conduit extending from the pump discharge. The gas is released by using a gas-transfer foot that is positioned next to and is preferably attachable to the pump base or to the metal-transfer conduit. Preferably, the conduit (and/or discharge) in which the gas is released comprises two sections: a first section having a first cross-sectional area and a second section downstream of the first section and having a second cross-sectional area, wherein the second cross sectional area is larger than the first cross-sectional area. Preferably, the gas is released into or near the second section so that the gas is released into an area of relatively lower pressure.

As used herein, the term "molten metal" means any metal or combination of metals in liquid form, such as aluminum, copper, iron, zinc and alloys thereof. The term "gas" means any gas or combinations of gases, including argon, nitrogen, chlorine, fluorine, Freon, and helium, which are released into molten metal.
Known pumps for pumping molten metal (also called "molten metal pumps") include a pump base (also called a housing or casing), one or more inlets, an inlet being an opening to allow molten metal to enter a pump chamber (and is usually an opening in the pump base that communicates with the pump chamber), a pump chamber, which is an open area formed within the pump base, and a discharge, which is a channel or conduit communicating with the pump chamber (in an axial pump the pump chamber and discharge may be the same structure or different areas of the same structure) leading from the pump chamber to the molten metal bath in which the pump base is submerged. A rotor, also called an impeller, is mounted in the pump chamber and is connected to a drive shaft. The drive shaft is typically a motor shaft coupled to a rotor shaft, wherein the motor shaft has two ends, one end being connected to a motor and the other end being coupled to the rotor shaft. The rotor shaft also has two ends, wherein one end is coupled to the motor shaft and the other end is connected to the rotor. Often, the rotor shaft is comprised of graphite, the motor shaft is comprised of steel, and the two are coupled by a coupling, which is usually comprised of steel.
As the motor turns the drive shaft, the drive shaft turns the rotor and the rotor pushes molten metal out of the pump chamber, through the discharge, which may be an axial, tangential or any type of discharge, and into the molten metal bath. Most molten metal pumps are gravity fed, wherein gravity forces molten metal through the inlet (either a top inlet, bottom inlet or both) and into the pump chamber as the rotor pushes molten metal out of the pump chamber.
Molten metal pump casings and rotors usually employ a bearing system comprising ceramic rings wherein there is one or more rings on the rotor that align with rings in the pump chamber (such as rings at the inlet (which is usually at the top of the pump chamber and/or bottom of the pump chamber) when the rotor is placed in the pump chamber. The purpose of the bearing system is to reduce damage to the soft, graphite components, particularly the rotor and pump chamber wall, during pump operation. Known bearing systems are described in U.S. Pat. Nos. 5,203,681, 5,591,243 and 6,093,000 to Cooper, the respective disclosures of which are incorporated herein by reference. Further, U.S. Pat. No. 2,948,524 to Sweeney et al., U.S. Pat. No. 4,169,584 to Mangalick, U.S. Pat. No. 5,203,681 to Cooper and U.S. Pat. No. 6,123,523 to Cooper (the disclosure of U.S. Pat. No. 6,123,533 to Cooper is also incorporated herein by reference) all disclose molten metal pumps.
Furthermore, copending U.S. patent application Ser. No. 10/773,102 to Cooper, filed on Feb. 4, 2004 and entitled "Pump With Rotating Inlet" discloses, among other things, a pump having an inlet and rotor structure (or other displacement structure) that rotate together as the pump operates in order to alleviate jamming. The disclosure of this copending application is incorporated herein by reference.
The materials forming the components that contact the molten metal bath should remain relatively stable in the bath. Structural refractory materials, such as graphite or ceramics, that are resistant to disintegration by corrosive attack from the molten metal may be used. As used herein "ceramics" or "ceramic" refers to any oxidized metal (including silicon) or carbon-based material, excluding graphite, capable of being used in the environment of a molten metal bath. "Graphite" means any type of graphite, whether or not chemically treated. Graphite is particularly suitable for being formed into pump components because it is (a) soft and relatively easy to machine, (b) not as brittle as ceramics and less prone to breakage, and (c) less expensive than ceramics.
Three basic types of pumps for pumping molten metal, such as molten aluminum, are utilized: circulation pumps, transfer pumps and gas-release pumps. Circulation pumps are used to circulate the molten metal within a bath, thereby generally equalizing the temperature of the molten metal. Most often, circulation pumps are used in a reverbatory furnace having an external well. The well is usually an extension of a charging well where scrap metal is charged (i.e., added).
Transfer pumps are generally used to transfer molten metal from the external well of a reverbatory furnace to a different location such as a ladle or another furnace. Examples of transfer pumps are disclosed in U.S. Pat. No. 6,345,964 B1 to Cooper, the disclosure of which is incorporated herein by reference, and U.S. Pat. No. 5,203,681.
Gas-release pumps, such as gas-transfer pumps, circulate molten metal while releasing a gas into the molten metal. In the purification of molten metals, particularly aluminum, it is frequently desired to remove dissolved gases such as hydrogen, or dissolved metals, such as magnesium, from the molten metal. As is known by those skilled in the art, the removing of dissolved gas is known as "degassing" while the removal of magnesium is known as "demagging." Gas-release pumps may be used for either of these purposes or for any other application for which it is desirable to introduce gas into molten metal. Gas-release pumps generally include a gas-transfer conduit having a first end that is connected to a gas source and a second submerged in the molten metal bath. Gas is introduced into the first end and is released from the second end into the molten metal. The gas may be released downstream of the pump chamber into either the pump discharge or a metal-transfer conduit extending from the discharge, or into a stream of molten metal exiting either the discharge or the metal-transfer conduit. Alternatively, gas may be released into the pump chamber or upstream of the pump chamber at a position where it enters the pump chamber. A system for releasing gas into a pump chamber is disclosed in U.S. Pat. No. 6,123,523 to Cooper, and in copending U.S. application Ser. No. 10/773,101 entitled System for Releasing Gas Into Molten Metal filed on Feb. 4, 2004.
The advantage of a system for releasing gas into molten metal within the confines of a metal-transfer conduit is that the gas and metal should have a better opportunity to thoroughly interact. One problem with releasing gas into a metal-transfer conduit is that, in some systems, the conduit (called a gas-transfer conduit) that transfers the gas from a gas source into the molten metal stream typically extends into the metal-transfer conduit, usually extending downward from the top of the metal-transfer conduit, and disrupts the flow of molten metal passing through the conduit and creating a low-pressure area behind the portion of the gas-transfer conduit extending into the metal-transfer conduit. The low-pressure area can interfere with the released gas mixing with molten metal passing through the metal-transfer conduit because, among other things, the gas immediately rises into the low-pressure area instead of mixing with molten metal throughout the metal-transfer conduit. This can create a phenomenon known as "burping" because a large gas bubble will build up in the low pressure area and then be released from the discharge instead of thoroughly mixing with the molten metal.


A seismic survey design generation method is disclosed for generating seismic survey design data for performing a seismic survey. The survey design data purposefully violates Freznel zone constraints related to source and/or receiver bin sizes by providing exceptionally small bin sizes. In particular, the seismic survey design generation method and apparatus therefor generates seismic survey design data where the Freznel zone constraints are violated in order to obtain enhanced resolution seismic images not possible in the prior art.

Data for imaging underground geologic formations is used to locate various deposits of, e.g., oil, gas, water, as well as various precious metal and mineral deposits. However, to obtain such data, seismic surveys of the geologic underground formations is typically required. However, such seismic surveys are time consuming and expensive. Moreover, such surveys become more expensive as the bin sizes for the seismic signal sources and receivers decrease.
It is well known in the geophysical industry that there are limits to the resolution of seismic data obtained from performing a seismic survey, and such limits are well known to be dictated by the Fresnel zone constraints as such are applied to the survey site and the underground depth to be imaged. Provided in Appendix A herein is a collection of prior art references that assert that the Fresnel zone constraints are the limiting factor on the resolution that can obtain in transforming seismic survey data to a corresponding seismic image wherein geologic features at great depths can be resolved. In particular, it is well known in the seismic survey art that if high enough signal frequencies are transmitted into the ground at great depths, the constraints asserted by the Freznel Zone are presumed to be limits as to the extent that such seismic data can be effectively noise reduced and resolution enhanced as one skilled in the art will understand.
Accordingly it would be advantageous to have a method and system for enhancing seismic data obtained from a seismic survey wherein additional resolution beyond what would be dictated by the Fresnel zone constraints even though the seismic survey may be substantially more expensive to perform.
Definitions
    Super stack: A method of summing adjacent bins in larger bins which will decrease spatial resolution and increase fold.    Fold: The number of traces that are summed into a single summed trace, wherein the summed traces are received from a single receiver bin. As an example, if the bin size is 15 feet (on each side of rectangular bins), and there are 10 traces received in each receiver bin, then binning the trace data into 30 foot bins yields a fold of 40, and binning the trace data into 45 foot bins yields a fold of 90.    Seismic Signals: Downwardly propagated in ground signals generated at one or more predetermined surface sources, wherein such signals (e.g., shock waves) are purposefully generated at the source(s) so that the reflections of such signals (these reflection also denoted as "traces" herein) from one or more subsurface geologic formations are detected by receivers positioned relative to the source(s) at a predetermined surface locations for thereby detecting these reflections.    Trace: A reflection of seismic signals from a single source that is received at single receiver.    Trace Data: Data obtained from one or more traces for use in modeling or imaging underground geologic formations or structures.    Common Depth Points: Subsurface reflection points of seismic signals, wherein these reflection points are presumed to be at a substantially common in ground depth. For a given pair of a seismic signal source and a seismic signal receiver, such Common Depth Points for this pair are presumed to be generally midway between the source and receiver of the pair. Common Depth Points are also referred to as "common mid-points" in the art.    Regular Pattern of Common Depth Points: A desired pattern in the traces for common depth points of a given subsurface depth. In particular, the pattern is expected to have a substantially uniform resolution at the given depth.

Generation and use of seismic survey designs violating Freznel zone constraints


A primary drainage process, a core aging process, a spontaneous water imbibition process, a forced water imbibition process, a spontaneous hydrocarbon imbibition process, and a secondary drainage process is conducted on a rock sample. For each of the primary drainage process, the spontaneous water imbibition process, the forced water imbibition process, the spontaneous hydrocarbon imbibition process, and the secondary drainage process, a pressure distribution and a fluid saturation distribution are measured across multiple locations along the rock sample. For each of the locations, the pressure distribution and the fluid saturation distribution are combined to produce a capillary pressure bounding curve and scanning loop for the rock sample, and a relative permeability bounding curve and scanning loop are determined at least based on the measured fluid saturation and pressure distributions at the respective location. A wettability distribution along the rock sample is determined based on the bounding curves and scanning loops.

For multiphase fluid flow, the relative permeability, capillary pressure, and wettability are dynamic parameters that govern the multiphase flow behavior in porous media. The study of such parameters can be valuable in evaluating and predicting hydrocarbon recovery from hydrocarbon-containing reservoirs.
The characteristics of capillary pressure, relative permeability, and wettability distribution in such reservoirs, however, can be complex. Furthermore, both capillary pressure and relative permeability can depend not only on fluid saturation but also on fluid saturation path and history, which is a phenomenon that is sometimes referred to as hysteresis. Several hydrocarbon recovery processes involve changing directions of fluid saturation paths, such as water alternating gas (WAG) enhanced oil recovery (EOR) processes and cyclic injection processes, such as huff and puff operations in heavy oil recovery.

Determination of scanning loops of capillary pressure and relative permeability curves and wettability distribution of rock samples


A semiconductor device includes: a waveguide mesa structure including at least an optical absorption layer for photoelectric conversion; and a heat radiation semiconductor layer in contact directly with at least a part of the optical absorption layer for heat radiation from the optical absorption layer, and the heat radiation semiconductor layer being lower in refractive index and larger in energy band gap than the optical absorption layer.

1. Field of the Invention
The present invention relates to a semiconductor photodetector, and more particularly to a waveguide semiconductor photodetector to be used for a light receiving module or a light transmitting module in an optical communication system.
2. Description of the Related Art
Research and development to the waveguide semiconductor photodetector have been progressed (or a light receiving module or a light transmitting module in an optical communication system. The waveguide semiconductor photodetector has an optical absorption layer. A light is incident in parallel to a surface of the optical absorption layer. Even if the optical absorption layer is designed to be thin for obtaining high speed performances, then a sufficiently long waveguide length of the optical absorption layer ensures a high photoelectric conversion efficiency. The waveguide semiconductor photodetector may be designed for obtaining both a high speed response due to a shortened carrier traveling time and a high photoelectric conversion efficiency.
One of the conventional waveguide semiconductor photodetector is disclosed in Third Optoelectronics And Communications Conference Technical Digest, July 1998, pp. 354-355. FIG. 1 is a fragmentary cross sectional elevation view illustrative of a conventional waveguide semiconductor photodetector.
An n+xe2x88x92InP cladding layer 102 overlies a semi-insulating InP substrate 101. An n+xe2x88x92InAlGaAs optical guide layer 103 overlies on a selected region of the n+xe2x88x92InP cladding layer 102. The n+xe2x88x92InAlGaAs optical guide layer 103 has a thickness of 0.8 micrometers, and also has a refractive index which is an intermediate level between a core layer and a cladding layer. An i-InGaAs optical absorption layer 104 overlies the n+xe2x88x92InAlGaAs optical guide layer 103. The i-InGaAs optical absorption layer 104 has a thickness of 0.5 micrometers. A p+xe2x88x92InAlGaAs optical guide layer 105 overlies the i-InGaAs optical absorption layer 104. The p+xe2x88x92InAlGaAs optical guide layer 105 has a thickness of 0.1 micrometer. A p+xe2x88x92InP cladding layer 106 overlies the p+xe2x88x92InAlGaAs optical guide layer 105. A p+xe2x88x92InGaAs contact layer 107 overlies the p+xe2x88x92InP cladding layer 106. The lamination of the n+xe2x88x92InAlGaAs optical guide layer 103, the i-InGaAs optical absorption layer 104, the p+xe2x88x92InAlGaAs optical guide layer 105, the p+xe2x88x92InP cladding layer 106 and the p+xe2x88x92InGaAs contact layer 107 forms a waveguide mesa structure.
A silicon nitride film 108 extends over the n+xe2x88x92InP cladding layer 102 and also on side walls and a top of the waveguide mesa structure. The silicon nitride film 108 has a first opening over the p+xe2x88x92InGaAs contact layer 107, and second and third openings over the n+xe2x88x92InP cladding layer 102. N-electrodes 110 are provided in the second and third openings over the n+xe2x88x92InP cladding layer 102. A p-electrode 109 is provided in the first opening over the p+xe2x88x92InGaAs contact layer 107.
The n-electrodes 110 are provided in contact with the n+xe2x88x92InP cladding layer 102 relatively near the waveguide mesa structure so as to reduce a parasitic resistance. The i-InGaAs optical absorption layer 104 is designed to be thin, for example, at 0.5 micrometers in order to obtain a high speed response with a cut-off frequency of not less than 40 GHz at 3 dB-down. The waveguide structure ensures a high photoelectric conversion efficiency at 77%.
The above-described conventional waveguide semiconductor photodetector may reduce, a device resistance. The waveguide mesa structure is directly coated with a thin silicon nitride film, whereby a heat radiation characteristic is poor. An incidence of a high power light into the device is likely to result in an undesirable heat accumulation which may deteriorate or break the waveguide semiconductor photodetector.
In the above circumstances, the development of a novel waveguide semiconductor photodetector free from the above problems is desirable.
Accordingly, it is an object of the present invention to provide a novel waveguide semiconductor photodetector free from the above problems.
It is a further object of the present invention to provide a novel waveguide semiconductor photodetector with a reduced device resistance, a high performance and a high reliability to a heat generation due to an incidence of a high power light without deterioration and break-down.
The present invention provides a semiconductor device including: a waveguide mesa structure including at least an optical absorption layer for photoelectric conversion; and a heat radiation semiconductor layer in contact directly with at least a part of the optical absorption layer for heat radiation from the optical absorption layer, and the heat radiation semiconductor layer being lower in refractive index and larger in energy band gap than the optical absorption layer.


A mechanism is provided for making information about the virtual disk image file and/or its associated virtual image configuration file more readily available to a user. The virtual disk image file format is expanded to include fields in which information about the data in the file can be stored. Extensible information on file content, compatible HW configurations, compatible host OSes, timeout status, DRM status, patch state, and network topology, tag data for indexing, configuration files, saved state files, operation history data, and the like is stored in a location within a virtual disk image file that can be read without executing the virtual machine. This information can then be used to search the contents of the virtual disk image, to enforce usage policies, to provide extensibility for vendors, and the like.

To create a virtual machine (VM), virtual machine software, such as Microsoft's Virtual Server, starts an instance of a virtual machine creator that creates the desired VM from multiple stored files. As shown in FIG. 1, the virtual machine creator 10 creates a first VM (VM1) using a VM configuration file (VM Config1) that includes information explaining the machine (system) configuration of the VM to be created and a virtual hard disk (VHD1) that stores a virtual disk image file representing a hard drive (disk) in a VM environment. In other words, the files VHD1 and VM Config1 together provide the information needed by VM creator 10 to create VM1. Similarly, the files VHD2 and VM Config2 together provide the information needed by VM creator 10 to create VM2. As illustrated in FIG. 1, a saved state of the memory contents of the VM may be used by VM creator 10 to relaunch VM2 so that VM2 starts at a preselected saved state. Conventional virtual machine applications, such as Virtual VPC 2004 and Virtual Server 2005 from Microsoft Corporation, allow users to save the running state of a virtual machine and restore it at a later point of time. The saved state file contains all the memory contents of a VM at the point it was saved as well as the state of all the devices that were running in the VM.
As illustrated in FIG. 1, a virtual machine application needs a minimum of two files to launch a virtual machine. They are the virtual disk image file (VHD) and the virtual machine configuration file (VM CONFIG). The virtual machine creator application 10 may read information from this file and construct a virtual machine. However, to move a VM from one physical machine to another, the user has to move both the VHD and VM CONFIG files. Moreover, there is no way an administrator can enforce that a particular VM configuration file is used with a particular disk image. As a result, a user can create a new VM and attach a disk image to it, even if it is from the wrong one. Also, if virtual machines are check-pointed, then there are multiple saved state files that represent the virtual machine at different points in time. Maintaining all these saved state files can be a tedious process and make migration of virtual machines cumbersome. An improved VM migration technique is desired.
Virtual machine hard disks (VHDs) are virtualized in the form of files that reside on the native host file system. Each virtual hard disk type has its own standard file format that varies by VHD type. There are several types of VHDs; the following types of VHD formats are supported by Microsoft Virtual PC and Virtual Server:                Fixed hard disk;        Dynamic hard disk;        Differencing hard disk;
Unfortunately, as noted below, the file structures and file formats of conventional VHDs limit the uses of VHDs by the VM creator 10.
In particular, conventional VHD file formats provide a mechanism to layout the VM disk data in a file; however, conventional VHD file formats do not provide a mechanism to store information that provides more detail about what data is stored in the VHD and the characteristics of that data. Accordingly, to learn more about the stored VHD data from the disk image, the user has to attach the disk image to the VM, launch the VM using the VM creator 10, and then read the contents through the VM. This is an expensive and tedious operation.
To illustrate this, suppose a user needs the ability to find out if a VM has been patched or not. If it has been patched, the user would like to know to what level it has been patched and whether it is safe to start up the VM or not. This information is very valuable as the user would prefer to find out the patch information and make a decision if he/she wants to start a virtual machine. By checking the patch state, the user can potentially stop an un-patched VM from connecting to the network and create a vulnerable point on the network. Unfortunately, as just noted, the user conventionally has to start the VM to check the patch state. A solution is desired whereby the user may check the VHD data without starting the VM.
The conventional VHD file formats also do not provide any mechanism to store information that can help a policy engine to make decisions on whether a virtual disk image could be used by a particular hardware environment, or by a particular user. As a result, the conventional VHD file formats do not permit a user to create a virtual disk image and install operating systems and/or applications and to safely distribute the VM on the Internet. This is because any virtual machine product which understands the current file format will be able to use the operating system and application present in the virtual disk image. It is desired to provide a mechanism whereby a policy engine can decide if a particular user may or may not use the operating system/application present in a particular virtual disk image.
The conventional VHD file formats further do not provide a mechanism to store information that specifies the type of physical hardware on which the operating system inside the virtual hard disk image can run. This is desirable since a VM can typically move from one physical machine to another, provided that some of the hardware components (e.g. processors) are identical. This knowledge is crucial to enable a VM system to decide if it can move a live VM to another physical machine. It is thus desirable to provide a mechanism by which a policy engine can decide if a particular VM can move from one physical machine to another physical machine.
The conventional VHD file formats do not provide a robust mechanism to enforce a timeout policy that would allow an administrator to publish disk images which can be used only for a certain period, or only during a certain period of time in the day. It is desirable to provide a mechanism by which the policy engine may monitor if the virtual disk image has expired or is unusable at a particular time of day.
The conventional VHD file formats do not provide any mechanism to store DRM information. Without any DRM information, the virtual disk image cannot be used as a vehicle for software distribution. It is desired to provide sufficient DRM protections so as to enable a software vendor to create a virtual disk image with its application installed in it for distribution on the Internet to users, who would be able to download their license keys separately to use the virtual disk image.
The conventional VHD file formats do not provide any mechanism to control the usage of a virtual disk image in a particular network environment such that, for example, a system administrator may setup certain virtual machines so that they can run only in a secure network environment. It is desired to create a VM environment in which an illegal user cannot get access to the virtual disk images and launch a virtual machine from a virtual disk image in an environment different from the intended one.
As a convenience to VM users, it is also desirable for VM users to be able to quickly search a virtual disk image to determine its contents. Conventionally, given a large number of disk images, if a user has to find a particular disk image, he has to attach the virtual disk image to a virtual machine and start it up to find out if it contains what he is looking for. The other option is for the user to uniquely name the disk images or to store them in separate uniquely named folders that may be very tedious to setup and maintain. A better way to search virtual disk images is desired.
In addition, the conventional virtual disk image file format does not allow third party vendors to add custom information without modifying the file format. This restricts the extensibility of the format. For example, an anti-virus product might want to store some information that indicates whether a virtual machine disk image was checked for infection. Unfortunately, in the conventional implementation of the VHD there is no way to store this information in the file without modifying the file format. An extensible mechanism is desired that enables metadata to be stored in a virtual machine disk image.
In conventional virtual disk image file formats, there is also no mechanism for a user to store notes related to the modifications made to a virtual disk image. Such a mechanism is desired.

Mechanism to store information describing a virtual machine in a virtual disk image


A vacuum cleaner includes a dirt tank, a tank cover mounted on the dirt tank, and a blower detachably mounted on the tank cover and including a main body. The blower forms a single handle which is located on a top face of the main body. Thus, the vacuum cleaner can be easily lifted up by one single hand of an operator due to the single handle located on a top face of the main body of the blower. A locking assembly for a vacuum cleaner including a tank cover and a blower detachably engaged with the tank cover is arranged between the tank cover and the blower. The locking assembly includes a latch, a resilient member and a locking shoulder, the resilient member being connected between the blower and the latch, the latch being pivotally mounted at the blower and engageable with the locking shoulder. Therefore, the blower is easily and reliably attached with or detached from the tank cover via the locking assembly which includes the latch and the locking shoulder simply latching with or detaching from each other.

Presently, one type of vacuum cleaner having a detachable blower may perform blowing or sucking operation. The detachable blower is commonly attached to or detached from a body of the vacuum cleaner via a locking assembly. When the vacuum cleaner needs to perform blowing operation, the blower is detached from the body for separately processing blowing operation, such as blowing debris from a machine table to the ground before sucking operation, or blowing dispersive debris or leaves together for conveniently vacuum or clearing. As shown in U.S. Pat. No. 4,880,364 and U.S. Patent Publication Number 2002/0108205, a vacuum cleaner having a detachable blower disclosed in either of them forms two hand grip portions on two opposite sides of the detachable blower for the user to grip the blower. However, for such a vacuum cleaner, the user must grip the two hand grip portions with both hands to lift the whole vacuum cleaner. If one hand of the user is wounded or carrying other objects, she/he can not lift the whole vacuum cleaner, thereby such a vacuum cleaner is inconvenient in use.
In a vacuum cleaner having a detachable blower, the body commonly includes a dirt tank and a tank cover located between the dirt tank and the blower. A drive motor and an impeller are mounted in a housing of the blower for generating low pressure suction force in the dirt tank to thereby suck debris, dust or liquid waste into the dirt tank through a hose mounted at the dirt tank. The vacuum cleaner has blowing and sucking function, and when it is used for blowing function, the blower is detached from the vacuum cleaner for independently processing blowing function. Accordingly, a locking assembly is arranged between the dirt tank and the blower, for attaching or detaching the blower from the dirt tank. However, referring to U.S. Patent Publication Number 2002/0138938, a locking assembly disclosed therein can not reliably lock the blower with the dirt tank, so the blower maybe accidentally break away from the dirt tank.

Vacuum cleaner having detachable blower and related locking assembly

Suzhou Cleva Electric Appliance Co. Ltd.


An improved carrier strap assembly for carrying a plurality of fishing rods and reels includes a first elongate strap or spine member having opposed adjustable size loops at each end thereof. A second strap means is mounted perpendicularly to said first strap means and slidably therealong the one of the opposed end loops. A third strap means is mounted slidably along the first strap means between the two end loops. Both the second and third strap means are fitted with hook and loop fasteners provided for selectably releasable engagement of one side of the strap means to the other side thereof. In the operation, the bottom loop on the first strap is enlarged until it fits around the fishing rod handles under the reels and then is cinched up until snug. At the opposite end of the first strap, the top loop on the first strap is adjusted in size until the second strap is positioned to extend around the upper end of the fishing poles under the first full eyelet on the rod. The second strap means is engaged around the fishing poles and around itself until the hoop and loop fasteners retain same in a desired loose or snug position. The third strap means is moved along the spine of the first strap means and fitted around the fishing rods and around itself until securly engaged to allow the portion of the first strap means between the third strap means and the bottom loop to be utilized as a carrying handle or shoulder strap for carrying the fishing rods and reels.

This invention relates generally to carriers for fishing equipment, namely fishing rods and reels and, more particularly, to an adjustable, multiple strap assembly for carrying a plurality of fishing rods and reels.
Heretofore, carriers for fishing rods and reels have been of a type that enclosed the entire rod and reel in a fabric such as shown in U.S. Pat. Nos. 3,575,327 and 3,972,144, or cover the reel and rod handle of a plurality of fishing rod assemblies, such as shown in U.S. Pat No. 3,674,190, or provide individual pouches to surround the rod handle and reel for one or more fishing rods as shown in U.S. Pat. Nos. 4,136,748 and 4,726,141.
The fabric or man-made sheet material used in these rod and reel covers is bulky and tends to collect dirt and/or undesirable foreign matter which may accumulate near water, boats, etc. and find its way into the interior of the fabric, or carrier pouches, covers and the like.
A need has developed for a simplified fishing equipment carrier capable of maintaining a plurality of assembled or partly assembled fishing rods and reels in ordered orientation without the need for a large flexible sheet-type structure which may accumulate water, dirt, grime, etc. while performing its intended function. Further, the provision of large sheet type fabric structures in fishing rod and reel carriers requires that each carrier have a minimum of fabric material which may not always be needed if the number of fishing rods and reels carried is less than the maximum number supportable by the carrier structure.
Therefore, it is an object of the present invention to provide a new and improved carrier for efficiently transporting a plurality of assembled fishing rod and reel assemblies.
Another object of the present invention is the provision of a carrier for assembled fishing rods and reels which adjustably provide for efficient carrying of differing number of assembled fishing rods and reels.