1. A method of reducing noise in a vehicle propelled by an electric motor having a plurality of phases, the method comprising the steps of:
observing noise produced within the vehicle for at least one of the plurality of phases;
determining a transfer function between the noise produced by the at least one of the plurality of phases; and
applying the transfer function to produce a control signal for the motor, wherein the control signal is asymmetric with respect to the at least one of the plurality of electrical phases to thereby adjust acoustic signals produced by the electric motor.
2. The method of claim 1 wherein the applying step comprises generating the control signal so as to reduce the noise produced within the vehicle with the acoustic signals.
3. The method of claim 1 further comprising the step of adjusting the control signal for the motor in response to feedback measurements obtained by an acoustic sensor.
4. The method of claim 1 further comprising the step of adjusting the control signal for the motor in response to a change in vehicle speed.
5. The method of claim 1 further comprising the step of adjusting the control signal for the motor in response to a change in vehicle loading.
6. A device having active acoustic damping, the device comprising:
a motor comprising a plurality of independently actuatable regions;
a noise sensor configured to measure a noise and to provide a noise measurement as a function thereof and
a controller configured to receive the noise measurement and to provide a control signal to the motor as a function of the noise measurement, wherein the control signal comprises a plurality of phases, each phase corresponding to one of the independently actuatable regions, and wherein the controller is further configured to adjust the plurality of phases with respect to each other to thereby produce acoustic vibrations with the motor.
7. The device of claim 6 wherein the vibrations are configured to cancel at least a portion of the noise measured by the noise sensor.
8. The device of claim 6 wherein the controller is further configured to produce the control signal using a transfer function of the noise.
9. The device of claim 6 wherein the device is a vehicle.
10. The device of claim 6 wherein the device is an unmanned underwater vehicle (UUV).
11. A method of actively damping a noise with a motor, the method comprising the steps of:
obtaining a measurement of the noise;
processing the measurement to produce a control signal for the motor as a function of the noise; and
providing the control signal to the motor to thereby adjust an acoustic signal produced by the motor, wherein the acoustic signal is configured to produce a tone that cancels at least a portion of the noise.
12. The method of claim 11 wherein the processing step comprises applying an inverting transfer function to the measurement.
13. The method of claim 11 wherein the control signal comprises a plurality of phase controls, each provided to an independently-actuatable phase of the motor.
14. The method of claim 11 wherein the processing step comprises altering one of the plurality of phase controls to be unequal to the remaining phase controls.
15. The method of claim 14 wherein the altering step comprises altering a magnitude of the unequal one of the plurality of phase controls.
16. The method of claim 14 wherein the altering step comprises altering a frequency of the noise canceling portion.
17. A noise canceling control system for a motor, the control system comprising a processor and memory coupled to a noise sensor, wherein die memory is configured to store instructions for the processor, the instructions comprising:
a first code module configured to receive a noise measurement from the noise sensor; and
a second code module configured to provide a control signal to the motor in response to the noise measurement to thereby produce a vibration with the motor, wherein the vibration produces a tone configured to cancel at least a portion of the noise at the noise sensor.
18. A noise-canceling control system for a device having a motor, the control system comprising:
means for generating a control signal for the motor, wherein the control signal comprises a plurality of phases; and
means for adjusting at least one of the plurality of phases of the control signal to thereby produce a vibration with the motor, wherein the vibration produces a tone that cancels at least a portion of the noise.
19. A noise-canceling control system for a device having a motor, the control system comprising:
means for receiving a measurement of the noise;
means for processing the measurement to produce a control signal for the motor as a function of the noise; and
means for providing the control signal to the motor to thereby adjust an acoustic signal produced by the motor, wherein the acoustic signal is configured to produce a tone that cancels at least a portion of the noise.
20. A system for reducing noise in a vehicle propelled by an electric motor having a plurality of phases, the system comprising:
means for observing noise produced within the vehicle for at least one of the plurality of phases;
means for determining a transfer function between the noise produced by the at least one of the plurality of phases; and
means for applying the transfer function to produce a control signal for the motor, wherein the control signal is asymmetric with respect to the at least one of the plurality of electrical phases to thereby adjust acoustic signals produced by the electric motor.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method for separating water from a saline solution using a directional solvent, the method comprising:
a) providing a directional solvent;
b) providing a saline solution comprising water and at least one salt at an initial salt concentration;
c) making an emulsion of the saline solution in the directional solvent in liquid form;
d) heating the directional solvent before or after contact with the saline solution to produce a first phase that includes the directional solvent and a concentration of water from the saline solution dissolved in the directional solvent, and a second phase that includes a highly concentrated remainder of the saline solution;
e) separating the first phase from the second phase;
f) cooling the first phase after the separation to precipitate the water from the directional solvent, wherein the precipitation is a liquid-liquid phase separation, wherein the water is precipitated with a salt concentration substantially less than the initial salt concentration of the saline solution, and wherein the concentration of water that dissolves in the directional solvent is at least 10 times greater than the concentration of the directional solvent in the precipitated water;
g) removing the precipitated water from the directional solvent; and
h) reusing the directional solvent in multiple repetitions of (b) through (g),
wherein the water is dissolved in and precipitated from the solvent in an atmosphere with a pressure below 10 atm.
2. A method for separating water from a saline solution using a directional solvent, the method comprising:
a) providing a directional solvent, wherein the directional solvent includes a compound with a hydrophilic hydroxide group, and wherein the hydrophilic hydroxide group binds to water from the saline solution;
b) providing a saline solution comprising water and at least one salt at an initial salt concentration;
c) making an emulsion of the saline solution in the directional solvent in liquid form;
d) heating the directional solvent before or after contact with the saline solution to produce a first phase that includes the directional solvent and a concentration of water from the saline solution dissolved in the directional solvent, and a second phase that includes a highly concentrated remainder of the saline solution;
e) separating the first phase from the second phase;
f) cooling the first phase after the separation to precipitate the water from the directional solvent, wherein the precipitation is a liquid-liquid phase separation, wherein the water is precipitated with a salt concentration substantially less than the initial salt concentration of the saline solution, and wherein the concentration of water that dissolves in the directional solvent is at least 10 times greater than the concentration of the directional solvent in the precipitated water;
g) removing the precipitated water from the directional solvent; and
h) reusing the directional solvent in multiple repetitions of (b) through (g).
3. The method of claim 2, wherein the hydrophilic hydroxide group is part of a carboxyl group.
4. The method of claim 3, wherein the directional solvent includes a carboxylic acid that incorporates the carboxyl group.
5. The method of claim 4, wherein the carboxylic acid has an unbranched aliphatic chain.
6. The method of claim 5, wherein the unbranched aliphatic chain has a length from 6 to 13 carbon atoms.
7. The method of claim 2, wherein the directional solvent is heated to a temperature of no more than 110\xb0 C. to dissolve water from the saline solution into the directional solvent.
8. The method of claim 2, wherein the saline solution is a product of oil or gas extraction.
9. A method for separating water from a saline solution using a directional solvent, the method comprising:
a) providing a directional solvent, wherein the directional solvent is a solid at temperatures of 15\xb0 C. and below;
b) providing a saline solution comprising water and at least one salt at an initial salt concentration;
c) making an emulsion of the saline solution in the directional solvent in liquid form;
d) heating the directional solvent before or after contact with the saline solution to produce a first phase that includes the directional solvent and a concentration of water from the saline solution dissolved in the directional solvent, and a second phase that includes a highly concentrated remainder of the saline solution;
e) separating the first phase from the second phase;
f) cooling the first phase after the separation to precipitate the water from the directional solvent, wherein the precipitation is a liquid-liquid phase separation, wherein the water is precipitated with a salt concentration substantially less than the initial salt concentration of the saline solution, and wherein the concentration of water that dissolves in the directional solvent is at least 10 times greater than the concentration of the directional solvent in the precipitated water;
g) removing the precipitated water from the directional solvent; and
h) reusing the directional solvent in multiple repetitions of (b) through (g).
10. The method of claim 9, wherein the directional solvent includes a compound with a hydrophilic hydroxide group, and wherein the hydrophilic hydroxide group binds to water from the saline solution.
11. The method of claim 9, wherein the directional solvent is heated to a temperature of no more than 110\xb0 C. to dissolve water from the saline solution into the directional solvent.
12. A method for separating water from a saline solution using a directional solvent, the method comprising:
a) providing a directional solvent;
b) providing a saline solution comprising water and at least one salt at an initial salt concentration;
c) making an emulsion of the saline solution in the directional solvent in liquid form;
d) heating the directional solvent before or after contact with the saline solution to a temperature of no more than 110\xb0 C. to produce a first phase that includes the directional solvent and a concentration of water from the saline solution dissolved in the directional solvent, and a second phase that includes a highly concentrated remainder of the saline solution;
e) separating the first phase from the second phase;
f) cooling the first phase after the separation to precipitate the water from the directional solvent, wherein the precipitation is a liquid-liquid phase separation, wherein the water is precipitated with a salt concentration substantially less than the initial salt concentration of the saline solution, and wherein the concentration of water that dissolves in the directional solvent is at least 10 times greater than the concentration of the directional solvent in the precipitated water;
g) removing the precipitated water from the directional solvent; and
h) reusing the directional solvent in multiple repetitions of (b) through (g).
13. The method of claim 12, further comprising using dielectrophoresis to separate the precipitated water from the directional solvent.
14. The method of claim 12, wherein the directional solvent is heated using energy from a low-temperature heat source of no greater than 40\xb0 C.
15. The method of claim 12, wherein separation of the water from the saline solution using the directional solvent is a first stage in a multi-stage desalination process, the method further comprising subjecting the precipitated water, after extraction, to a second stage of desalination to reach a higher level of purity.
16. The method of claim 15, wherein the second stage of desalination includes reverse osmosis or flash distillation.
17. The method of claim 12, wherein the saline solution is a product of oil or gas extraction.
18. The method of claim 17, wherein the saline solution is fracking water or produced water.
19. The method of claim 12, wherein the directional solvent includes a compound with a hydrophilic hydroxide group, and wherein the hydrophilic hydroxide group binds to water from the saline solution.
20. The method of claim 12, wherein the directional solvent is heated to a temperature of no more than 75\xb0 C. to dissolve water from the saline solution into the directional solvent.