초록 ▼

A method of marine seismic surveying, whereby a seismic streamer is towed in a body of water while deploying three (3) sensors in close proximity to each other. In one embodiment of the invention, the first sensor generates a first signal indicative of pressure of the water, the second sensor genera

A method of marine seismic surveying, whereby a seismic streamer is towed in a body of water while deploying three (3) sensors in close proximity to each other. In one embodiment of the invention, the first sensor generates a first signal indicative of pressure of the water, the second sensor generates a second signal indicative of vertical movement of water, and the third sensor generates a third signal indicative of vertical movement of the streamer relative to the water. A seismic signal is generated in the water and the resulting signal is detected with each of the three (3) sensors simultaneously during time intervals following the generation of the seismic signal. The second signal is combined with the third signal to generate a fourth signal that measures vertical movement of the water with noise due to streamer vibration attenuated. The first signal is combined with the fourth signal to give a signal that attenuates the ghost due to the water surface. In a second embodiment of the invention, the third sensor is sensitive to the pressure in the water and the vertical motion of the sensor. By combining the output of the three sensors, a substantially noise-free and ghost-free seismic signal is obtained.

대표청구항 ▼

A method of marine seismic surveying, whereby a seismic streamer is towed in a body of water while deploying three (3) sensors in close proximity to each other. In one embodiment of the invention, the first sensor generates a first signal indicative of pressure of the water, the second sensor genera

A method of marine seismic surveying, whereby a seismic streamer is towed in a body of water while deploying three (3) sensors in close proximity to each other. In one embodiment of the invention, the first sensor generates a first signal indicative of pressure of the water, the second sensor generates a second signal indicative of vertical movement of water, and the third sensor generates a third signal indicative of vertical movement of the streamer relative to the water. A seismic signal is generated in the water and the resulting signal is detected with each of the three (3) sensors simultaneously during time intervals following the generation of the seismic signal. The second signal is combined with the third signal to generate a fourth signal that measures vertical movement of the water with noise due to streamer vibration attenuated. The first signal is combined with the fourth signal to give a signal that attenuates the ghost due to the water surface. In a second embodiment of the invention, the third sensor is sensitive to the pressure in the water and the vertical motion of the sensor. By combining the output of the three sensors, a substantially noise-free and ghost-free seismic signal is obtained. sed in a film. 9. The photoselective absorbing filter of claim 2, wherein the light selective absorbing coloring material is uniformly dispersed in a film. 10. The photoselective absorbing filter of claim 3, wherein the light selective absorbing coloring material is uniformly dispersed in a film. 11. The photoselective absorbing filter of claim 1, wherein the light selective absorbing coloring material is dispersed in a solvent comprising an alcohol, ant a glass is coated with the dispersion using a sol-gel method. 12. The photoselective absorbing filter of claim 2, wherein the light selective absorbing coloring material is dispersed in a solvent comprising an alcohol, and a glass is coated with the dispersion using a sol-gel method. 13. The photoselective absorbing filter of claim 3, wherein the light selective absorbing coloring material is dispersed in a solvent comprising an alcohol, and a glass is coated with the dispersion using a sol-gel method. 14. A color display device comprising the photoselective absorbing filter of claim 1. 15. A color display device comprising the photoselective absorbing filter of claim 2. 16. A color display device comprising the photoselective absorbing filter of claim 3. mode, the vehicle speed is greater than the speed constant K4, and the vehicle acceleration is less than the acceleration constant K5. 13. The method of claim 12 wherein the speed constant K4 is at least 50 kph. 14. The method of claim 12 wherein the speed constant K4 is at least 95 kph. 15. The method of claim 12 wherein the acceleration constant K5 is less than 1.5 g. 16. The method of claim 12 wherein the acceleration constant K5 is less than 0.8 g. 17. The method of claim 12 wherein the slip constant K6 is in the range of 2 to 8% slip. 18. The method of claim 12 wherein the slip constant K6 is in the range of 3 to 4% slip. 19. A computer readable medium storing a computer program for ABS stability control, said computer program comprising: computer readable code for determining whether a first rear wheel is in an ABS mode; computer readable code for determining whether the first rear wheel is in an apply mode; computer readable code for determining whether a second rear wheel is in a release mode; computer readable code for calculating an adjusted wheel slip if the first rear wheel is in the ABS mode, the first rear wheel is in the apply mode, and the second rear wheel is in the release mode; and computer readable code for determining a control mode for the first rear wheel using the adjusted wheel slip. 20. The computer readable medium of claim 19, the computer program further comprising: computer readable code for selecting a slip offset as the lesser of a first constant K1, or a second constant K2 times vehicle speed with the product added to a third constant K3; and computer readable code for adding the slip offset to a measured wheel slip from the first rear wheel to calculate the adjusted wheel slip. 21. A system for ABS stability control, comprising: means for determining whether a first rear wheel is in an ABS mode; means for determining whether the first rear wheel is in an apply mode; means for determining whether a second rear wheel is in a release mode; means for calculating an adjusted wheel slip if the first rear wheel is in the ABS mode, the first rear wheel is in the apply mode, and the second rear wheel is in the release mode; and means for determining a control mode for the first rear wheel using the adjusted wheel slip. 22. The system of claim 21 wherein the means for calculating an adjusted wheel slip further comprises: means for selecting a slip offset as the lesser of a first constant K1, or a second constant K2 times vehicle speed with the product added to a third constant K3; and means for adding the slip offset to a measured wheel slip from the first rear wheel to calculate the adjusted wheel slip. 23. A computer readable medium storing a computer program for ABS stability control, said computer program comprising: computer readable code for determining whether a first front wheel is in an ABS mode; computer readable code for determining whether the first front wheel is in an apply mode; computer readable code for determining whether a second front wheel is in a release mode; computer readable code for determining whether a vehicle speed is greater than a speed constant K4; computer readable code for determining whether a vehicle acceleration is less than an acceleration constant K5; computer readable code for calculating an adjusted wheel slip by adding a slip constant K6 to a measured wheel slip for the first front wheel if the first front wheel is in the ABS mode, the first front wheel is in the apply mode, the second front wheel is in the release mode, the vehicle speed is greater than the speed constant K4, and the vehicle acceleration is less than the acceleration constant K5; and computer readable code for determining a control mode for the first front wheel using the adjusted wheel slip. 24. A system for ABS stability control, comprising: means for determining whether a first front wheel is in an ABS mode; means for determining whether the fir