1. A pharmaceutical composition for release control of methylphenidate comprising:
a plurality of particles comprising a core material containing methylphenidate and a polymer coating layer formed on the core material,
wherein the plurality of particles are identical in terms of the composition of the polymer in the polymer coating layer, but are divided into two or more particle groups based on the average thickness of the polymer coating layer, and
wherein the particle groups comprise a first particle group having an average coating layer thickness of 1 to 30 \u03bcm, and a second particle group having an average coating layer thickness of 45 to 250 \u03bcm.
2. The pharmaceutical composition according to claim 1, wherein the polymer coating layer comprises a single layer or two or more layers.
3. The pharmaceutical composition according to claim 2, wherein, in the polymer coating layer comprising two or more layers, each layer is identical or different in terms of the composition of the polymer.
4. The pharmaceutical composition according to claim 1, wherein the particles further comprise a coating selected from a sub-coating inside the polymer coating layer and an over-coating outside the polymer coating layer.
5. The pharmaceutical composition according to claim 1, wherein the polymer of the polymer coating layer is one or more selected from a group consisting of a water-insoluble polymer, a water-soluble polymer, an enteric polymer, and a gastric polymer.
6. The pharmaceutical composition according to claim 1, wherein the particles have an average diameter of 30 to 3500 \u03bcm.
7. The pharmaceutical composition according to a claim 1, wherein the particle groups further comprise a third particle group.
8. The pharmaceutical composition according to claim 1 7, wherein the first particle group has an average coating layer thickness of 2 to 30 \u03bcm, and the second particle group has an average coating layer thickness of 45 to 90 \u03bcm.
9. The pharmaceutical composition according to claim 7, wherein the weight ratio of the first particle group:the second particle group:the third particle group is 1:0.1-10:0.1-10.
10. The pharmaceutical composition according to claim 1, wherein the release profile of the pharmaceutical composition tested according to the method 2(paddle method) of \u201c36. release test method\u201d of the Korean Pharmacopoeia, 8th edition (KP VIII) in 500 mL of water at 50 rpm exhibits:
5 to 50% of the total drug is released within 1 hour,
10 to 65% of the total drug is released within 2 hours,
20 to 80% of the total drug is released within 4 hours,
30 to 95% of the total drug is released within 6 hours, and
50% or more of the total drug is released within 8 hours.
11. The pharmaceutical composition according to claim 10, wherein the release profile of the pharmaceutical composition tested according to the method 2 (paddle method) of \u201c36. release test method\u201d of KP VIII in 500 mL of water at 50 rpm exhibits:
10 to 40% of the total drug is released within 1 hour,
15 to 50% of the total drug is released within 2 hours,
30 to 75% of the total drug is released within 4 hours,
50 to 90% of the total drug is released within 6 hours, and
70% or more of the total drug is released within 8 hours.
12. The pharmaceutical composition according to claim 1, wherein the core material and the polymer coating layer further comprise one or more selected from a group consisting of a sugar, a sugar alcohol, a polymer material, a colorant, an aromatic, a sweetener, a surfactant, a lubricant, a stabilizer, an antioxidant, a foaming agent, paraffin, wax, and a plasticizer.
13. The pharmaceutical composition according to claim 12, wherein the plasticizer is one or more selected from a group consisting of acetyl triethyl citrate, dibutyl phthalate, tributyl citrate, triethyl citrate, acetyl triethyl citrate, propylene glycol, triacetin, polyethylene glycol, diethyl phthalate, dibutyl sebacate, diethyl sebacate, cetyl alcohol, stearyl alcohol, and cetostearyl alcohol.
14. The pharmaceutical composition according to claim 1, wherein the pharmaceutical composition is an oral formulation.
15. The pharmaceutical composition according to claim 14, wherein the oral formulation is an orally disintegrating tablet, a chewable tablet, a capsule, a general tablet, a granule, or a syrup.
16. The pharmaceutical composition according to claim 7, wherein the difference between the average coating layer thickness of the second particle group and the third particle group is 10 to 80 \u03bcm.
17. The pharmaceutical composition according to claim 1, wherein the polymer of the polymer coating layer is water-insoluble ethyl acrylate-methyl methacrylate-chlorotrimethylammoniumethyl methacrylate copolymer.
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 seismic data telemetry system, comprising:
a seismic vessel;
a seismic data gathering unit in operative connection with at least one seismic sensor;
at least one of a seismic data telemetry transmitter and telemetry receiver disposed on the data gathering unit;
at least one of a seismic data telemetry receiver and telemetry transmitter disposed on the seismic vessel;
at least one directionally sensitive antenna disposed on one of the seismic vessel and the data gathering unit, the antenna operatively coupled to the at least one of the telemetry transmitter and receiver;
means for determining a geodetic position of the vessel associated with the vessel;
means for determining a geodetic position of the data gathering unit associated with the data gathering unit;
a geodetic position telemetry transceiver and omnidirectional antenna associated with each of the vessel and the data gathering unit;
means for determining a geodetic direction between the vessel and the data gathering unit in response to position data transmitted using the geodetic position telemetry transceiver; and
means for orienting and maintaining an orientation of a sensitive direction of the directionally sensitive antenna toward a corresponding antenna on the other one of the data gathering unit and the seismic vessel, the corresponding antenna operatively coupled to the at least one of the telemetry receiver and transmitter the means for orienting operative in response to the means for determining geodetic direction.
2. The system of claim 1 wherein the directionally sensitive antenna comprises a parabolic reflector rotatably mounted to the at least one of the gathering unit and the seismic vessel, and the means for rotating comprises a motor rotationally coupled to the reflector.
3. The system of claim 2 further comprising a directional sensor coupled to the reflector, and wherein the means for rotating comprises means for comparing a direction measured by the directional sensor to the geodetic direction.
4. The system of claim 3 wherein the directional sensor comprises a two channel magnetometer.
5. The system of claim 1 wherein the means for determining geodetic direction comprises a global positioning system receiver disposed on each of the gathering unit and the seismic vessel.
6. The system of claim 1 wherein the directionally sensitive antenna comprises a plurality of dipole antennas each coupled to a respective output of a phase shifter, and the means for rotating comprises means for determining a phase shift to be applied to each antenna such that a combined sensitivity thereof has a direction corresponding to the geodetic direction, the means for determining phase shift operatively coupled to the phase shifter.
7. The system of claim 1 wherein the means for orienting comprises a signal amplitude detector operatively coupled to the means for rotating, and the means for rotating comprises means for stopping rotation when a detected telemetry signal amplitude reaches a maximum value.
8. The system of claim 7 wherein the directionally sensitive antenna comprises a parabolic reflector rotatably mounted to the at least one of the gathering unit and the seismic vessel, and the means for rotating comprises a motor rotationally coupled to the reflector.
9. The system of claim 7 wherein the directionally sensitive antenna comprises a plurality of dipole antennas each coupled to a respective output of a phase shifter, and the means for rotating comprises means for determining a phase shift to be applied to each antenna such that a combined sensitivity thereof has a direction corresponding to a direction of maximum telemetry signal amplitude, the means for determining phase shift operatively coupled to the phase shifter.
10. The system of claim 1 wherein the seismic sensor is disposed in an ocean bottom cable.