1. A space perception device comprising:
a transceiver unit transmitting and receiving a signal;
a processing unit analyzing signals transmitted and received through the transceiver unit to search location information of an obstacle at a space; and
a vibration unit providing a user with location information of an obstacle at a space in response to a control of the processing unit,
wherein the vibration unit includes a plurality of vibrators having different three-dimensional coordinates.
2. The space perception device of claim 1, wherein the processing unit comprises:
a signal analyzing unit analyzing signals transmitted and received through the transceiver unit; and
a coordinate determining unit determining a three-dimensional coordinate on a location of an obstacle at a space, based on an analyzed result of the signal analyzing unit.
3. The space perception device of claim 2, further comprising:
a control unit controlling the coordinate determining unit,
wherein the control unit selects at least one of the plurality of vibrators by comparing a three-dimensional coordinate of the obstacle determined at the coordinate determining unit and three-dimensional coordinates of the plurality of vibrators.
4. The space perception device of claim 3, wherein the control unit varies a coordinate axis of the three-dimensional coordinate.
5. The space perception device of claim 1, wherein the plurality of vibrators provides a user with location information of an obstacle at a space through vibration.
6. The space perception device of claim 1, wherein the plurality of vibrators is formed of a piezoelectric element.
7. The space perception device of claim 1, wherein the transceiver unit transmits at least two transmission signals in different directions, and the at least two transmission signals transmitted in different directions have different modulation values.
8. The space perception device of claim 7, wherein the transceiver unit selectively receives signals corresponding to the at least two transmission signals transmitted in different directions according to a modulation value.
9. The space perception device of claim 8, wherein the transceiver unit includes an array of transmitters and receivers to transmit at least two transmission signals in different directions and to receive at least two transmission signals from different directions.
10. The space perception device of claim 1, wherein the transceiver unit includes first to third transceivers configured to be directed in different directions.
11. The space perception device of claim 10, wherein the first to third transceivers include first to third image collectors collecting images with respect to different directions, respectively.
12. The space perception device of claim 11, wherein the first to third image collectors measure focal distances on different images on the basis of an infrared ray.
13. The space perception device of claim 12, wherein when the first to third collectors collects the same image, the same images collected by the first to third collectors have different focal distances.
14. The space perception device of claim 1, further comprising:
a stick unit searching information associated with an obstacle on a footpath of a user.
15. The space perception device of claim 1, wherein the plurality of vibrators is configured to include a sensor measuring a function of the human body.
16. The space perception device of claim 1, wherein the processing unit includes a GPS device detecting information about a location of a user.
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 composition, comprising:
methyl esters derived from vegetable oils, the methyl esters comprising less than about 3% by weight of saturated fatty acid methyl esters; and
the composition having a cloud point of less than about \u221230\xb0 C.
2. The composition of claim 1, wherein the methyl esters consist essentially of methyl oleate, methyl linoleate and methyl linolenate.
3. The composition of claim 2, wherein the methyl linolenate comprises less than about 10% by weight of the methyl esters.
4. The composition of claim 3, wherein the methyl stearate comprises less than about 0.1% by weight of the methyl esters.
5. The composition of claim 3, wherein the methyl linoleate comprises at least about 50% by weight of the methyl esters.
6. The composition of claim 4, wherein the methyl linoleate comprises at least about 60% by weight of the methyl esters.
7. The composition of claim 1, wherein the cloud point is less than about \u221235\xb0 C.
8. The composition of claim 1, wherein the cloud point is less than about \u221240\xb0 C.
9. The composition of claim 1, wherein the cloud point is less than about \u221245\xb0 C.
10. The composition of claim 1, wherein the cloud point is less than about \u221250\xb0 C.
11. The composition of claim 1, wherein the cloud point is less than about \u221255\xb0 C.
12. The composition of claim 1, wherein the methyl esters comprise less than about 2% saturated methyl esters.
13. The composition of claim 1, wherein the methyl esters comprise less than about 1.5% saturated methyl esters.
14. The composition of claim 1, wherein the methyl esters comprise less than about 0.5% saturated methyl esters.
15. The composition of claim 1, wherein the vegetable oils from which the methyl esters are derived comprise soy oil.
16. The composition of claim 1, further comprising a petroleum based component.
17. The composition of claim 16, wherein the petroleum based component comprises fossil fuel derived diesel fuel.
18. The composition of claim 1, comprising less than about 1% methyl stearate.
19. The composition of claim 1, comprising less than about 0.5% methyl stearate.
20. The composition of claim 1, comprising less than about 0.1% methyl stearate.
21. The composition of claim 1, further comprising animal fat derived methyl esters.
22. A method of lowering the cloud point of methyl esters derived from vegetable oil, comprising:
mixing vegetable derived methyl esters, urea and alcohol with sufficient heat to form a homogenous mixture;
cooling the homogeneous mixture to a temperature where a solid phase and a liquid phase are formed, the solid phase being enriched in saturated fatty acid methyl esters and the liquid phase being enriched in unsaturated fatty acid methyl esters;
separating the solid phase from the liquid phase; and
removing alcohol and unused urea from the liquid phase to form a liquid composition having a cloud point of less than about \u221230\xb0 C. and less than about 3% by weight saturated fatty acid methyl esters.
23. The method of claim 22, wherein the alcohol comprises methanol.
24. The method of claim 23, further comprising, before the step of forming the homogeneous mixture, mixing vegetable derived oil, sodium hydroxide and methanol to form the vegetable derived methyl esters.
25. The method of claim 24, wherein the homogeneous mixture contains methanol in an amount of about 3 to 10 times by weight of the amount of the fatty acid methyl ester.
26. The method of claim 25, wherein excess methanol is provided in the step of mixing the vegetable derived oil, sodium hydroxide and methanol to form the vegetable derived methyl esters, whereby adding methanol during the step of forming the homogeneous mixture is unnecessary.
27. The method of claim 23, further comprising separating glycerin from the vegetable derived methyl esters before the step of forming the homogeneous mixture.
28. The method of claim 22, wherein the ratio of urea to methyl esters in the homogeneous mixture is from about 0.9:1 to about 1:1.
29. The method of claim 22, wherein the solid phase is separated from the liquid phase by filtration, centrifugation, sedimentation, or decantation of the liquid phase.
30. The method of claim 22, wherein the liquid composition comprises less than about 2 percent by weight of saturated fatty acid methyl esters.
31. The method of claim 22, wherein the liquid composition comprises less than about 1.5 percent by weight of saturated fatty acid methyl esters.
32. The method of claim 22, wherein the removal of the alcohol is by evaporation.
33. The method of claim 22, wherein the removal of the alcohol is by applying vacuum.
34. The method of claim 22, wherein the removal of unused urea is by washing with acidified water, wherein the washed unused urea is separated by a liquid-liquid centrifugal extractor or by a gravity separation.
35. The method of claim 22, wherein the yield of the liquid composition is at least 43% by weight of the vegetable-derived methyl esters used to form the homogeneous mixture.
36. The method claim of 35, wherein cloud point of the liquid composition is less than \u221234\xb0 C.
37. The method claim of 35, wherein cloud point of the liquid composition is less than \u221240\xb0 C.
38. The method claim of 35, wherein cloud point of the liquid composition is less than \u221250\xb0 C.