What is claimed is:
1. A method of handling comminuted cellulosic fibrous material in a cylindrical vessel having a first diameter, a discharge having a second diameter at least 20% less than the first diameter, and a discharge agitator having a power requirement, said method comprising:
(a) storing or treating the material in the vessel at the first diameter portion thereof;
(b) passing the material through a transition from the first diameter to the second diameter;
(c) agitating the material with the discharge agitator while in the transition;
(d) discharging the material from the vessel through the discharge; and
practicing (b) and (c) so that the power requirement of the discharge agitator is at least 10% less than the power requirement without the transition.
2. A method as recited in claim 1 wherein (b) is practiced using a substantially smooth interior surface, substantially frusto-conical, transition.
3. A method as recited in claim 2 wherein (b) is further practiced using a substantially frusto-conical transition having an interior surface with a slope angle of between about 40-50 degrees to an imaginary line substantially perpendicular to the direction of flow of material through the transition.
4. A method as recited in claim 2 wherein the transition comprises a first transition; and further comprising (e) passing the material through a single-convergent second transition prior to passing the material through the first transition, and wherein (b) and (c) are practiced so that the power requirement is at least 20% less.
5. A method as recited in claim 4 wherein (e) is practiced by passing the material through a change in cross-section from substantially circular to substantially race-track-oval, and from substantially race-track-oval back to substantially circular.
6. A method as recited in claim 2 wherein (c) is practiced by rotating an agitator, having at least two arms with paddles, about an axis substantially parallel to and substantially concentric with the direction of flow of material through the transition, and wherein (b) and (c) are practiced so that the power requirement is at least 20% less.
7. A method as recited in claim 6 wherein (c) is further practiced by rotating an agitator having a deflector cone.
8. A method as recited in claim 1 wherein the vessel initially does not have the transition; and comprising the further step (e) of retrofitting the transition into the vessel prior to the practice of (b) and (c).
9. A method as recited in claim 1 wherein (a) is practiced by digesting or impregnating the material.
10. A method as recited in claim 9 wherein (a) is further practiced by removing liquid from the vessel through a screen assembly just before the transition in the direction of movement of the material through the discharge.
11. A method as recited in claim 2 comprising the further step (e) of moving the transition during the practice of (b).
12. A vessel assembly for handling comminuted cellulosic fibrous material, comprising:
a substantially cylindrical substantially upright vessel having a first diameter material storing or treating portion above a second diameter discharge, said second diameter at least 20% less than said first diameter; and
a substantially smooth interior surface, substantially frusto-conical transition between said first and second diameter portions.
13. An assembly as recited in claim 12 wherein said transition interior surface comprises polished stainless steel.
14. An assembly as recited in claim 12 wherein said transition interior surface has a slope angle of between about 5-50 degrees to the vertical, the first diameter is at least about 10 feet, and the second diameter is at least about 2 feet.
15. An assembly as recited in claim 12 further comprising an agitator disposed in said discharge and said transition which agitates material in said transition.
16. An assembly as recited in claim 15 wherein said transition interior surface slope angle is between about 40-50 degrees to the horizontal.
17. An assembly as recited in claim 16 wherein said vessel comprises a digester or impregnation vessel; and further comprising a withdrawal screen assembly located in said vessel just above said transition.
18. An assembly as recited in claim 12 wherein said transition comprises a first transition; and further comprising a single-convergent second transition disposed above said first transition.
19. An assembly as recited in claim 18 wherein said second transition changes in cross-section, from most remote from said first transition toward said first transition, from substantially circular to substantially race-track-oval, and from substantially race-track-oval back to substantially circular.
20. An assembly as recited in claim 15 wherein said agitator has at least two arms with paddles, and is mounted for rotation about a substantially vertical axis substantially concentric with said second diameter.
21. A method of handling comminuted cellulosic fibrous material in a cylindrical vessel having a first diameter, a discharge having a second diameter at least 20% less than the first diameter, said method comprising:
(a) storing or treating the material in the vessel at the first diameter portion thereof;
(b) passing the material through a substantially smooth interior surface, substantially frusto-conical transition from the first diameter to the second diameter; and
(c) discharging the material from the vessel through the discharge.
22. A method as recited in claim 21 wherein (b) is further practiced without agitating the material within the transition, and using a substantially frusto-conical transition having an interior surface with a slope angle of between about 5-20 degrees to an imaginary line substantially parallel to the direction of flow of material through the transition.
23. A method as recited in claim 22 wherein the transition comprises a first transition; and further comprising (d) passing the material through a single-convergent second transition prior to passing the material through the first transition.
24. A method as recited in claim 23 wherein (d) is practiced by passing the material through a change in cross-section from substantially circular to substantially race-track-oval, and from substantially race-track-oval back to substantially circular.
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 radio access network system having a synchronous server and at least one node, wherein
the synchronous server comprises:
a clock generator configured to periodically generate a clock; and
a synchronous message transmitter configured to generate a synchronous message for notifying information regarding the generated clock, and to transmit the generated synchronous message to the node using an IP packet; and
the node comprises:
a time calculator configured to obtain a time of receiving the synchronous message; and
a clock correction processor configured to calculate a clock correction value in accordance with the time of receiving the synchronous message and the information regarding the clock notified by the synchronous message, and to correct a generated timing of a clock in the node in accordance with the clock correction value.
2. A radio communication method in a radio access network system having a synchronous server and at least one node, the method comprising the steps of:
generating a clock periodically in the synchronous server;
generating a synchronous message for notifying information regarding the generated clock in the synchronous server;
transmitting the generated synchronous message to the node using an IP packet in the synchronous server;
calculating a clock correction value in accordance with a time of receiving the synchronous message and the information regarding the clock notified by the synchronous message in the node; and
correcting a generated timing of a clock in accordance with the clock correction value in the node.
3. A synchronous server in a radio access network system having at least one node, the server comprising:
a clock generator configured to periodically generate a clock; and
a synchronous message transmitter configured to generate a synchronous message for notifying information regarding the generated clock, and to transmit the generated synchronous message to the node using an IP packet.
4. The synchronous server according to claim 3, wherein the synchronous message transmitter sets a time of transmitting the synchronous message as the information regarding the clock in the synchronous message.
5. A node in a radio access network system having a synchronous server, the node comprising:
a receiver configured to receive a synchronous message for notifying information regarding a clock generated in the synchronous server;
a time calculator configured to obtain a time of receiving the synchronous message; and
a clock correction processor configured to calculate a clock correction value in accordance with the time of receiving the synchronous message and the information regarding the clock notified by the synchronous message, and to correct a generated timing of a clock in the node in accordance with the clock correction value.
6. The node according to claim 5, wherein the time calculator measures a reception interval of the synchronous message, and calculates the clock correction value without using the synchronous message when the reception interval of the synchronous message is more than a predetermined threshold.
7. The node according to claim 5, the node further comprising a memory configured to associate a time of transmitting set in the synchronous message with the time of receiving the synchronous message in the node, upon receiving the synchronous message.
8. The node according to claim 7, wherein the time calculator obtains the time of transmitting the synchronous message and the time of receiving the synchronous message from the memory, calculates a transmission interval of the synchronous message and a reception interval of the synchronous message, and calculates the clock correction value in accordance with a comparison between the transmission interval and the reception interval.