1. A system for measuring a concentration of magnetic ballast in a slurry comprising:
a detection conduit surrounded by a first detection coil, the detection conduit configured to receive the slurry, and the first detection coil comprising a first section and a second section both positioned coaxially along the detection conduit;
a reference conduit surrounded by a first reference coil;
a second detection coil surrounding the detection conduit and positioned between the first and second sections of the first detection coil along a common axis of the detection conduit;
a second reference coil surrounding the reference conduit and positioned in proximity to the first reference coil;
an AC power source configured to generate a magnetic field in the first detection coil and the first reference coil; and
a measurement device configured to measure a differential induced voltage between the second detection coil and the second reference coil to determine the concentration of the magnetic ballast in the slurry based on the measured differential induced voltage.
2. The system of claim 1, wherein the slurry is a static slurry.
3. The system of claim 1, wherein the slurry is a moving slurry.
4. The system of claim 1, wherein the first detection coil and the first reference coil are symmetrical.
5. The system of claim 1, wherein the first and second detection coils and the first and second reference coils are positioned on a common plane of symmetry perpendicular to each other.
6. The system of claim 1, wherein the first and second detection coils and the first and second reference coils are located on a common plane of symmetry parallel to each other.
7. The system of claim 1, wherein the first and second detection coils are identical to the first and second reference coils.
8. The system of claim 1, configured to measure a concentration of magnetic ballast in a range of about 0.1 mgl to about 500,000 mgl.
9. The system of claim 1, wherein the differential induced voltage between the second detection coil and the second reference coil voltage is proportional to the concentration of the magnetic ballast in the slurry.
10. A method for measuring a concentration of magnetic ballast in a slurry comprising:
providing a system comprising
a detection conduit surrounded by a first detection coil, comprising a first section and a second section both positioned coaxially along the detection conduit;
a reference conduit surrounded by a first reference coil;
a second detection coil surrounding the detection conduit and positioned between the first and second sections of the first detection coil along a common axis of the detection conduit; and
a second reference coil surrounding the reference conduit and positioned in proximity to the first reference coil;
introducing the slurry into the detection conduit;
generating a magnetic field in the first detection coil and the first reference coil; and
measuring an induced voltage between the second detection coils and the second reference coil to determine the concentration of the magnetic ballast in the slurry based on the measured differential induced voltage.
11. The method of claim 10, wherein introducing the slurry into the detection conduit comprises at least a partially immersing the system in a component of a wastewater treatment system.
12. The method of claim 11, wherein the component includes a component selected from the group consisting of a reaction tank, a mixing tank, and aeration tank, a settling tank, a clarifier, a conduit, line or pipe, an impregnation subsystem, a return activated sludge subsystem, a weighting agent recovery subsystem, a wasting system, and combinations thereof.
13. The method of claim 10, wherein the concentration of the magnetic ballast in the slurry is in a range of about 0.1 mgl to about 500,000 mgl.
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 network device, comprising:
a memory including first and second groups of memory locations, wherein the device is configured to implement a primary queue in the first group of memory locations and a congestion queue in the second group of memory locations;
wherein the network device is configured to:
receive one or more packets to be transmitted by the network device and, in response, store the one or more packets in one or more memory locations of the primary queue implemented in the first group of memory locations;
receive information specifying that a particular output port of a downstream network device is congested; and
based at least in part on the information specifying that the particular output port of the downstream network device is congested and that a route for the one or more packets includes the particular output port of the downstream network device, transfer the one or more packets from within the primary queue implemented in the first group of memory locations to one or more memory locations of the congestion queue implemented in the second group of memory locations.
2. The network device of claim 1, wherein the one or more packets include information specifying that the one or more packets are to be transmitted by the network device via a first of a plurality of output ports of the network device, and wherein the one or more packets further include information usable to determine that the one or more packets are to be transmitted via the particular output port of the downstream network device;
wherein the first group of memory locations is for use by the network device to store packets to be transmitted via the first output port of the network device, but not packets to be transmitted via other ones of the plurality of output ports.
3. The network device of claim 2, wherein the network device is configured to:
make a determination that the particular output port of the downstream network device is no longer congested; and
transmit at least one packet in the congestion queue based at least in part on the determination.
4. The network device of claim 2, wherein a third group of memory locations is for use by the network device to store packets to be transmitted via the first output port of the network device, but not packets to be transmitted via other ones of the plurality of output ports; and
wherein the first group of memory locations is for use by the network device to store packets having a first traffic class, and wherein the third group of memory locations is for use by the network device to store packets having a different traffic class.
5. The network device of claim 1,
wherein the network device is configured to transfer the one or more packets to the second group of memory locations based, at least in part, on one of the one or more packets reaching a head of the primary queue.
6. The network device of claim 1, wherein the network device is configured to determine the route for the one or more packets based, at least in part, on information contained in one or more packet headers corresponding to the one or more packets.
7. A method, comprising:
a first network device receiving a plurality of packets to be routed;
the first network device storing the plurality of packets in a primary queue implemented in one or more memory locations of a first group of locations in a memory of the first network device; and
the first network device transferring one or more of the plurality of packets from within the primary queue implemented by the first group of locations to one or more memory locations of a congestion queue implemented in a second group of locations in the memory of the first network device, wherein said transferring is based, at least in part, on an indication of congestion specifying congestion at a particular output port of a second network device and on information that indicates a route for the plurality of packets includes the particular output port of the second network device.
8. The method of claim 7, wherein the plurality of packets includes information specifying that the plurality of packets is to be transmitted by the first network device via a first of a plurality of output ports of the first network device, and wherein the one or more packets include information specifying that the one or more packets are to be transmitted via the particular output port of the second network device after arrival of the one or more packets at the second network device;
wherein the first group of memory locations is for use by the first network device to store packets to be transmitted via the first output port of the first network device, but not packets to be transmitted via other ones of the plurality of output ports.
9. The method of claim 7, further comprising the first network device scheduling the one or more packets for transmission to the second network device based, at least in part, on a determination that the particular output port of the second network device is no longer congested.
10. The method of claim 9, further comprising the first network device receiving from the second network device information usable to determine that the particular output port of the second network device is no longer congested.
11. The method of claim 7,
wherein said transferring the one or more packets is based, at least in part, upon the one or more packets reaching a head of the primary queue.
12. The method of claim 7, wherein said transferring the one or more of the plurality of packets is based, at least in part, on a traffic class corresponding to the one or more packets.
13. A device, comprising:
a memory system, including:
a primary queue implemented by a first group of memory locations; and
a congestion queue implemented by a second group of memory locations;
wherein the device is configured to:
receive an indication of congestion specifying congestion at a particular output port of a downstream network device;
receive a group of one or more packets;
store the received group of one or more packets in the primary queue; and
based at least in part on the received indication of congestion and on information indicating a path associated with the group of one or more packets includes the particular output port of the downstream network device, transfer the group of one or more packets from the primary queue to the congestion queue.
14. The device of claim 13, wherein the memory system further comprises:
a congestion queue control memory configured to store a plurality of entries corresponding to received indications of congestion at downstream network devices.
15. The device of claim 14, wherein the congestion queue control memory is a content addressable memory.
16. The device of claim 13, further comprising:
one or more additional primary queues;
wherein the primary queue and the one or more additional primary queues are configured to store packets corresponding to different traffic classes.
17. The device of claim 13, further comprising:
one or more additional congestion queues;
wherein the congestion queue and the one or more additional congestion queues are configured to store packets corresponding to different traffic classes.
18. The device of claim 13, wherein individual packets in the group of one or more packets include packet headers, and wherein individual ones of the packet headers specify one or more outputs of downstream network devices.
19. The device of claim 13, wherein the device is configured to:
determine that congestion at the particular output port of the downstream network device is alleviated; and
in response to said determining that the congestion is alleviated, transmit the group of one or more packets stored in the congestion queue to the downstream network device.
20. The device of claim 19, wherein said determining that the congestion is alleviated includes receiving a communication from the downstream network device subsequent to receiving the indication of congestion.