All The Claims

1. An image forming apparatus for forming a color image using color materials of a plurality of colors that include a basic color, black and at least one special color, comprising:
an input unit for inputting color image data for which an image is to be formed;
a color separation unit for generating color data in which the color image data has been separated into each of the plurality of colors; and
an image forming unit for forming a color image based upon the color data;
wherein said color separation unit generates the color data so that the color data has a region in which amount of the color material of the color black used is increased and amount of the color material of the special color used is increased as brightness declines in a low-brightness region in the hue of the special color.
2. The apparatus according to claim 1, wherein said color separation unit sets, as a high-brightness region, a brightness region from maximum brightness to a brightness corresponding to a maximum saturation that the color material of the special color is capable of reproducing; and
in the high-brightness region, generates color data in such a manner that the amount of color material of the special color used increases as brightness declines.
3. The apparatus according to claim 1, wherein said color separation unit sets, as an intermediate-brightness region, a brightness region from a lower-limit brightness of a high-brightness region to a brightness at which maximum saturation is obtained by a mixed color of the two basic colors;
in the intermediate-brightness region, generates color data in such a manner that the amounts of color materials of the two basic colors used increase as brightness declines with amount of color material of the special color used being maximized until a limit on total amount of the color materials used is reached; and
generates color data in such a manner that the amount of color material of the special color used decreases and amounts of color materials of the two basic colors used increase as brightness declines, after the amount of color materials used reaches the limit on total amount used.
4. The apparatus according to claim 1, wherein said color separation unit sets, as a low-brightness region, a brightness region from a lower-limit brightness of an intermediate-brightness region to a brightness at which maximum saturation is obtained by a mixed color of the special color and black; and
in the low-brightness region, generates color data in such a manner that the amounts of color materials of the two basic colors used decrease and amounts of the materials of the special color and black used increase as brightness declines.
5. The apparatus according to claim 1, wherein said color separation unit sets a brightness region from a lower-limit brightness of a low-brightness region to minimum brightness as a near-black region; and
in the near-black region, generates color data in such a manner that amount of color material of the special color used decreases and amount of material of the black color used increases as brightness declines.
6. The apparatus according to claim 1, wherein the color material of the special color expresses a brightness higher than that of a secondary color in a hue near the hue of the special color expressed by a mixed color of two of the basic colors.
7. The apparatus according to claim 1, wherein the color material of the special color has an unwanted absorption component of spectral reflectance that is smaller than that of two color materials, which have hues near the special color, from among the basic colors.
8. The apparatus according to claim 1, wherein in a case where a first mixed color obtained by mixing the color material of the special color and the material of the black color is adjusted to a hue and brightness that are the same as those of a second mixed color obtained by mixing two color materials, which have hues near the special color, from among the basic colors and the color material of the color black, an image based upon the first mixed color has an unwanted absorption component of spectral reflectance that is small in comparison with an image based upon the second mixed color.
9. The apparatus according to claim 1, wherein the special color is any color from among red, green and blue.
10. The apparatus according to claim 9, wherein the basic colors include cyan, magenta and yellow.
11. The apparatus according to claim 1, wherein said color separation unit uses a color material of a complementary color with respect to the special color instead of the material of the black color in a low-brightness region of the hue of the special color.
12. A method of controlling an image forming apparatus for forming a color image using color materials of a plurality of colors that include a basic color, black and at least one special color, said method comprising:
an input step of an input unit inputting color image data for which an image is to be formed;
a color separating step of a color separation unit generating color data in which the color image data has been separated into each of the plurality of colors; and
an image forming unit of an image forming unit forming a color image based upon the color data;
wherein the color data is generated at said color separation step so that the color data has a region in which amount of the color material of the color black used is increased and amount of the color material of the special color used is increased as brightness declines in a low-brightness region of the hue of the special color.
13. A computer-readable storage medium storing a computer program for implementing the image forming apparatus set forth in claim 1 by being run on a computer within the image forming apparatus.

The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.

What is claimed is:

1. A method for measuring an output multiplixer (OMUX) transfer function, comprising:
receiving a broadcast downlink signal from a satellite;
demodulating the broadcast downlink signal;
remodulating the demodulated signal; and
comparing the received broadcast downlink signal to the remodulated signal to estimate the OMUX transfer function of the satellite.
2. The method of claim 1, wherein the steps are performed by a receiver.
3. The method of claim 1, wherein input multiplexor effects are negligible.
4. The method of claim 1, wherein the remodulating includes accounting for traveling wave tube amplifier (TWTA) maps.
5. The method of claim 1, wherein the estimated OMUX transfer function comprises a ratio of the received broadcast downlink signal to the remodulated signal.
6. The method of claim 1, wherein the received broadcast downlink signal comprises an estimated OMUX output due to noise.
7. The method of claim 1, wherein the estimated OMUX transfer function includes bandwidth, flatness, and group delay.
8. The method of claim 1, further comprising utilizing the estimated OMUX transfer function to assist to layered modulation signal processing.
9. The method of claim 1, further comprising utilizing the estimated OMUX transfer function as part of satellite payload system monitoring.
10. An apparatus for measuring an output multiplixer (OMUX) transfer function, comprising:
means for receiving a broadcast downlink signal from a satellite;
means for demodulating the broadcast downlink signal;
means for remodulating the demodulated signal; and
means for comparing the received broadcast downlink signal to the remodulated signal to estimate the OMUX transfer function of the satellite.
11. The apparatus of claim 10, wherein the apparatus comprises a receiver.
12. The apparatus of claim 10, wherein input multiplexor effects are negligible.
13. The apparatus of claim 10, wherein the means for remodulating includes means for accounting for traveling wave tube amplifier (TWTA) maps.
14. The apparatus of claim 10, wherein the estimated OMUX transfer function comprises a ratio of the received broadcast downlink signal to the remodulated signal.
15. The apparatus of claim 10, wherein the received broadcast downlink signal comprises an estimated OMUX output due to noise.
16. The apparatus of claim 10, wherein the estimated OMUX transfer function includes bandwidth, flatness, and group delay.
17. The apparatus of claim 10, further comprising means for utilizing the estimated OMUX transfer function to assist to layered modulation signal processing.
18. The apparatus of claim 10, further comprising means for utilizing the estimated OMUX transfer function as part of satellite payload system monitoring.
19. A system for measuring an output multiplixer (OMUX) transfer function, comprising:
a downlink signal broadcast from a satellite;
a receiver configured to receive the downlink signal;
a demodulator within the receiver configured to demodulate the downlink signal;
a remodulator within the receiver configured to remodulate the demodulated signal; and
a comparator configured to compare the received downlink signal to the remodulated signal to estimate the OMUX transfer function of the satellite.
20. The system of claim 19, wherein input multiplexor effects are negligible.
21. The system of claim 19, wherein the remodulator accounts for traveling wave tube amplifier (TWTA) maps.
22. The system of claim 19, wherein the estimated OMUX transfer function comprises a ratio of the received broadcast downlink signal to the remodulated signal.
23. The system of claim 19, wherein the downlink signal received by the receiver comprises an estimated OMUX output due to noise.
24. The system of claim 19, wherein the estimated OMUX transfer function includes bandwidth, flatness, and group delay.
25. The system of claim 19, further comprising a layered modulation module configured to utilize the estimated OMUX transfer function to assist to layered modulation signal processing.
26. The system of claim 19, further comprising a system monitoring module configured to utilize the estimated OMUX transfer function as part of satellite payload system monitoring.

1. A process for preparing a rigid polyurethane foam, comprising
a) forming a reactive mixture consisting of
1) a polyol mixture that includes (i) a reaction product of a C2-C4 alkylene oxide with 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, or a mixture thereof, the reaction product having a hydroxyl functionality of 3.7 to 4.0 and a hydroxyl equivalent weight of from 100 to 130, (ii) 20 to 70% of a sorbitol or sucrose and glycerin initiated polyether polyol having an average functionality of 4.5 to 7 hydroxyl groups and a hydroxy equivalent weight of 100 to 175 (iii) 2 to 20% by weight of an ethylenediamine-initiated polyol having an equivalent weight of 100 to 225 and (iv) 0 to 15% by weight of a non-amine-initiated polyol having a functionality of 2.0 to 3.0 and a hydroxyl equivalent weight of 200 to 500;
2) at least one hydrocarbon, hydrofluorocarbon, hydrochlorofluorocarbon, fluorocarbon, dialkyl ether or fluorine-substituted dialkyl ether physical blowing agent; and
3) at least one polyisocyanate;
4) water;
5) one or more catalysts for the reaction of the polyols and water with the polyisocyanate;
6) a surfactant; and
7) optionally one or more of a filler, a colorant, an odor mask, a flame retardant, a biocide, an antioxidant, a UV stabilizer, an antistatic agent; and

b) subjecting the reactive mixture to conditions such that the reactive mixture expands and cures to form a rigid polyurethane foam.
2. The process of claim 1, wherein the alkylene oxide is ethylene oxide, propylene oxide or a mixture of ethylene oxide and propylene oxide.

The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.

What is claimed is:

1. In a tape drive system performing readwrite operations for a tape by inserting a tape cartridge into a tape drive, said tape cartridge having a tape on which servo and data tracks are arranged longitudinally and a predetermined servo pattern is recorded on each of said servo tracks, a method for stabilizing a servo system for said tape drive comprising the step of:
re-setting coefficients of a low-pass filter for servo control of said tape drive, each time said tape cartridge is inserted into said tape drive, in response to the characteristics of the inserted tape cartridge.
2. The method according to claim 1, further comprising the steps of:
reading a servo pattern recorded on the tape in said tape cartridge inserted into said tape drive;
performing a frequency analysis of said read servo pattern;
detecting, from frequency components obtained by said frequency analysis, a singularity that exceeds a predetermined spectrum range; and
setting said coefficients of said low-pass filter so as to cancel a power spectrum of said singularity.
3. The method according to claim 2, wherein said servo pattern consists of a pattern of repetitive magnetic transitions recorded in non-parallel directions, and said step for performing a frequency analysis of said servo pattern includes the steps of measuring intra-pattern and inter-pattern intervals in said repetitive pattern and performing a fast Fourier transform on the measured results.
4. The method according to claim 3, wherein said step for detecting a singularity includes the steps of setting multiple windows each having a predetermined frequency at its center, for data obtained by said fast Fourier transform, and detecting a singularity in each of said windows.
5. The method according to claim 4, wherein said step for detecting a singularity compares a median for all signal values in each of said windows with each of said signal values, and defines as said singularity a frequency of a signal value having a difference from said median which exceeds a predetermined threshold value.
6. The method according to one of claims 2 to 5, wherein said step for setting coefficients of a low-pass filter includes the steps of preparing multiple sets of filter coefficients in advance by simulation, and selecting a set of filter coefficients in accordance with said detected singularity.
7. A tape drive into which a tape cartridge is inserted, said tape cartridge having a tape on which servo and data tracks are arranged longitudinally and a predetermined servo pattern is recorded on each of said servo tracks, comprising:
servo control means including a low-pass filter for servo signals; and
means for re-setting coefficients of said low-pass filter each time a tape cartridge is inserted, in response to the characteristics of the inserted tape cartridge.
8. The tape drive according to claim 7, wherein said re-setting means comprises:
means for reading a servo pattern recorded on the tape in said tape cartridge inserted into said tape drive;
means for performing a frequency analysis of said servo pattern;
means for detecting, from frequency components obtained by said frequency analysis, a singularity that exceeds a predetermined spectrum range; and
means for setting said coefficients of said low-pass filter so as to cancel a power spectrum of said singularity.
9. The tape drive according to claim 8, wherein said servo pattern consists of a pattern of repetitive magnetic transitions recorded in non-parallel directions, and said means for performing a frequency analysis of said servo pattern includes means for measuring intra-pattern and inter-pattern intervals in said repetitive pattern and performing a fast Fourier transform on the measured results.
10. The tape drive according to claim 9, wherein said means for detecting a singularity includes means for setting multiple windows each having a predetermined frequency at its center, for data obtained by said fast Fourier transform, and detecting a singularity in each of said windows.
11. The tape drive according to claim 10, wherein said means for detecting a singularity compares a median for all signal values in each of said windows with each of said signal values, and defines as said singularity a frequency of a signal value having a difference from said median which exceeds a predetermined threshold value.
12. The tape drive according to one of claims 8 to 11, wherein said means for setting coefficients of said low-pass filter includes means for preparing multiple sets of filter coefficients in advance by simulation, and selecting a set of filter coefficients in accordance with said detected singularity.