| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | John Rice |
| Physics operator(s): | Robert Granetz |
| Engineering operator(s): | Unknown |
| Engineering Operator Run Comment |
| MP 312: Ohmic H-mode rotation profiles. Rice/Granetz |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Entered: Jul 7 2004 03:49:30:913PM |
| Author: To Be Determined |
| Session Leader Run Summary for 1021001 MP301* ITB Foot, Ip Scan This run got off to a slow start. The first few shots were dedicated to Ohmic ITBs, a few of which were obtained. The RF was firing late in the shots and since it appeared to be good, the plan was to move the ITB foot at lower current. This run was again plaqued with RF trips and H-L transitions. No good ITBs were obtained at lower current. |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:37:16:380PM |
| Author: To Be Determined |
| Physics operator summary for run 1021001 (Tuesday): MP 312: Ohmic H-mode rotation profiles Session leader: J. Rice Physics operator: R. Granetz Engineers in charge: Summary: The tokamak ran very reliably today, but we were not able to get EDA H-modes that transitioned to ITB's, due to a variety of issues, including difficulty in getting the RF to couple reliability into these shots. We tried loading a number of different starting discharges, which all worked as expected, but then tweaking the parameters failed to get the desired behavior. See John's session leader summary for more details. The beginning of the run was delayed by more than an hour in order to finish checking the repairs to the OH2 commutation pulse forming network, and to debug a problem with the TCI Bragg cell RF amplifier. Scorecard: 22 plasmas 2 fizzles 0 duds 1 tests 1 aborted and/or screwed up by computer problems ---------- 26 total ------------------------------------------------------------------------------- Engineering setup for Tuesday, 01 Oct 2002 MP 312: Ohmic H-mode rotation profiles Session leader: J. Rice Physics operator: R. Granetz Power Systems as on 1020926035 ECDC overnight in D2 at 2e-4 Torr, stopping by 07:00. Bake at 60 C overnight as well. Set up for possible ECDC in D2 between shots. Run begins at 09:00 and ends at 17:00. Power systems the same as on 1020926035 (0.8 MA, 3.1-5.4 T, lower single null) *** NOTE: *** We will have to begin the run with at least one commutation test to check the repair of yesterday's problem with OH2L. Gas setup: fill B-Top with 6 psi D2 Hybrid enabled (PG4) fill B-side lower with 1 psi Ar Hybrid enabled (PG1) fill B-side upper with 10 psi D2 Hybrid DISABLED (PG2) (for ECDC) fill C-side with 30 psi D2 Hybrid enabled (PG3) leave J-Bottom as is Hybrid DISABLED (PG5) Enable the following gate valves, assuming no vacuum problems: ECE, VUV, DNB ------------------------------------------------------------------------------- RF Setup: All 4 transmitters Run On by 07:00. ------------------------------------------------------------------------------- Run Plan: Repeat the best ohmic ITB shots from last Thursday's run (1020926), but this time with the argon puffing enabled, in order to get ion rotation and temperature profiles with the Hirex systems. ------------------------------------------------------------------------------- ECDC was done overnight, as well as a bake at 60 C. Hybrid coldstart done by the engineering group; no errors found Loaded PCS from shot 1000926035 (0.8 MA, 5.4 -> 3.1 -> 4.6 T). Programmed in a 40 ms argon pulse starting at t=0.35 s. Jim Irby reports that the TCI is out of service today, so I loaded in the NL_ZMETER wire from 1020903020 and adjusted the setting to 0.25, which should give us about the desired density of nl_04=7e19 m-2. We will have to begin the run with at least one commutation test to check the repair of yesterday's problem with OH2L. ------------------------------------------------------------------------------- There was a 1 hour delay to the start of the run in order to do some more work on the commutation circuits and to repair the TCI. Shot 01 -- Test. Charging test of OH2L PFN cap bank. OK. Next shot: go for plasma. Use z-meter for density feedback. Shot 02 -- Plasma. Disrupted at t=0.97 s ... not sure why, although it was not a VDE. There was bright spot on the J-antenna (wide2 view) at t=0.61 s, without any apparent deleterious effect. Density (with z-meter) was about right (0.8e20 m-2). TCI worked fine. ELMfree H-mode starts at t=0.77 s. Next shot: put NL_04 wire back (remove NL_ZMETER) Shot 03 -- Plasma. Disrupted at t=1.00 s. Virtually identical to the last shot. No bright spots on J-antenna this time though. ELMfree H-mode starts at t=0.77 s again. Note: I did not actually load the wire change to NL_04 for shot 3. Next shot: reduce argon puff from 40 to 30 ms. NL_04 wire has definitely been loaded for the next shot. Shot 04 -- Fizzle. Next shot: reduce pre-fill 2 ms and add -10 amps to IC_EF4 to reduce Bz0 a bit. Shot 05 -- Plasma. Good shot...ramped all the way down. Good ITB up until the RF turns on at t=1.2 s. Prf=3.0 MW. Looks like reducing the argon puff was the right thing to do. ITB shows up on the stored energy and the neutron rate. Next shot: move RXL in a little to try and get an EDA H-mode to start earlier. Shot 06 -- Plasma. Good shot. H-mode starts earlier (ELMfree), and ITB starts earlier (t=1.0 s), but stops after only a short time. Prf=2.2 MW from D and E only, because JR asked that J-port be turned off. Next shot: move RXU in a little starting earlier in the flattop (to try and get an EDA earlier, and start Btor re-rampup 50 ms earlier. Shot 07 -- Plasma. Good shot. ITB still is very short-lived. Prf=2.2 MW. Since the RF is working well, John has decided to switch gears and do the MP involving control of the foot of the ITB. The rest of the day will involve RF H-modes, rather than ohmic H-modes. Next shot: change the Btor programming to ramp down only to 4.6 T and stay there. The RF will fire earlier in the shot, in order to get us into H-mode. Shot 08 -- Plasma. Good shot. Lots of short H-modes, maybe because E-port was faulting alot. Btor=4.67 T (constant during Ip flattop). Current rise is getting slightly slower each shot. Next shot: reduce pre-fill puff by 1 ms, and reduce Btor to 4.47 T. Shot 09 -- Plasma. Good shot. Still had multiple H-modes. Both D and E had faults, and D then shut off. Btor=4.48 T. Current rise did indeed get a little faster. Next shot: no PCS changes Shot 10 -- Plasma. Good shot. Lots of short H-modes. Upper triang=0.3. Next shot: reduce RXU by 1 cm starting slightly before t=0.5 s to try and get higher triangularity and EDA H-modes. Shot 11 -- Plasma. Good shot. Still lots of short H-modes. Upper triang went up by about 0.03. Next shot: reduce RXU another 2 cm, and delay the start of RF. Shot 12 -- Plasma. Good shot. H-modes were delayed until t>1.1 s, even though RF was only delayed until t=0.7 s. Upper triang increased up to 0.40! First H-mode was ELMfree, 2nd was EDA. Next shot: increase RXU by 1 cm (halfway between the preceding two shots), and raise the density from nl_04=0.7e20 to 0.8e20 m-2. Shot 13 -- Plasma. Good shot. But we're still plagued by multiple short ELMfree H-modes, which is not what we want. Current startup is getting faster. Next shot: load segment 2 from shot 11 yesterday (1020930011), which had a good long EDA H-mode. (And constant Btor of 5.4 T). Also add 1 ms to pre-fill puff. Shot 14 -- Plasma. Good shot. Nice long steady EDA H-mode. No ITB, since the field stayed at 5.4 T. Prf=2.4 MW from D&E, and no faults. Next shot: reduce Btor to 5.1 T by t=0.5 s. Shot 15 -- Plasma. Good shot. Multiple EDA H-modes, leading to more ELMfree- like H-modes, not due to RF faults. Maybe it's the lower q due to the lower Btor. Prf=2.4 MW. Next shot: add 5 ms to argon puff, and repeat. See if this H-mode behavior repeats itself. Shot 16 -- Plasma. Good shot. Virtually the same as the previous shot, which is not the long EDA H-mode that we want. Next shot: reduce Btor to 4.8 T Shot 17 -- Plasma. Good shot. Again, lots of short H-modes. Current startup is slowing down again. Next shot: reduce Ip to 0.6 MA (It's been 0.8 MA all day up until now.) Also reduce pre-fill puff by 1 ms. Shot 18 -- Plasma. Good shot. 0.6 MA, 4.8 T. Prf=1-2 MW, mostly 1 MW. No H-modes. Next shot: reduce Btor to 4.5 T. Shot 19 -- Aborted. No-power shot cycle due to EF4 fault during INIT. Next shot: Btor=4.5 T. Shot 20 -- Plasma. Good shot. Another L-mode shot, even though Prf=1.5 MW. Btor=4.5 T. Next shot: repeat with higher RF power. Shot 21 -- Plasma. Good shot. Another L-mode shot. Prf=1.5+ MW. Next shot: at the request of the RF operator, reduce the lower triangularity by moving RXL out 2 cm. Also reduce pre-fill puff by 1 ms. Shot 22 -- Fizzle. Next shot: reduce pre-fill puff another 1 ms. Shot 23 -- Plasma. Good shot. Another L-mode shot. Next shot: load segment 2 from 1020925007 (0.8 MA, 4.5 T, low triangularities). Shot 24 -- Plasma. Good shot. Ip=0.8 MA, Btor=4.5 T. Got H-modes back. There's also an ITB, although the central YAG density didn't work on this shot. The GPC is cutoff, however, which is a good ITB indicator. Next shot: reduce Ip to 0.6 MA. Also reduce pre-fill puff another 1 ms. Shot 25 -- Plasma. Good shot. Ip=0.6 MA, Btor=4.5 T. Three short H-modes, the last of which might have developed an ITB. Prf=1+ MW. Next shot: no PCS changes Shot 26 -- Plasma. Good shot. One short little H-mode. End of run. |
| Session Leader Comments | |||
| Oct 1 2002 11:12:12:740AM | 1021001001 | John Rice | test |
| Oct 1 2002 11:12:25:943AM | 1021001002 | John Rice | OH H-mode |
| Oct 1 2002 11:18:22:467AM | 1021001003 | John Rice | OH H-mode, disrupted |
| Oct 1 2002 11:31:40:423AM | 1021001004 | John Rice | phizzle |
| Oct 1 2002 11:46:14:010AM | 1021001005 | John Rice | good OH ITB, but confused by ICRF late |
| Oct 1 2002 12:05:20:087PM | 1021001006 | John Rice | earlier OH ITB, but short-lived |
| Oct 1 2002 12:18:16:327PM | 1021001007 | John Rice | early H-L transition killed ITB |
| Oct 1 2002 12:43:18:753PM | 1021001008 | John Rice | 4.67 T, multiple RF trips, no ITB |
| Oct 1 2002 01:05:13:130PM | 1021001009 | John Rice | 4.47 T, multiple RF trips, no ITB |
| Oct 1 2002 01:05:21:987PM | 1021001010 | John Rice | 4.47 T, multiple RF trips, no ITB |
| Oct 1 2002 01:42:21:793PM | 1021001011 | John Rice | 4.47 T, multiple H-L, no ITB |
| Oct 1 2002 01:42:35:790PM | 1021001012 | John Rice | 4.47 T, multiple H-L, no ITB |
| Oct 1 2002 02:11:36:407PM | 1021001013 | John Rice | many trips |
| Oct 1 2002 02:11:00:660PM | 1021001014 | John Rice | 5.4 T, good EDA, no RF trips |
| Oct 1 2002 02:19:44:390PM | 1021001015 | John Rice | 5.1 T, many H-L |
| Oct 1 2002 02:41:07:540PM | 1021001016 | John Rice | 5.1 T, many H-L |
| Oct 1 2002 02:51:10:910PM | 1021001017 | John Rice | 4.8 T, many H-L |
| Oct 1 2002 03:09:56:983PM | 1021001018 | John Rice | 4.8 T, 600 kA, no H-mode, E port problems |
| Oct 1 2002 03:28:23:690PM | 1021001019 | John Rice | test |
| Oct 1 2002 03:37:53:303PM | 1021001020 | John Rice | no H-mode, no ITB |
| Oct 1 2002 03:55:51:180PM | 1021001021 | John Rice | no H-mode, no ITB |
| Oct 1 2002 04:24:30:453PM | 1021001022 | John Rice | phizzle |
| Oct 1 2002 04:24:02:047PM | 1021001023 | John Rice | no H-mode, no ITB |
| Oct 1 2002 04:47:34:560PM | 1021001024 | John Rice | .8 kA, ITB |
| Oct 1 2002 04:54:14:480PM | 1021001024 | John Rice | .6 kA, trips |
| Oct 1 2002 04:54:25:823PM | 1021001025 | John Rice | .6 kA, trips |
| Physics Operator Comments | |||
| Sep 30 2002 05:05:21:680PM | Robert Granetz | Engineering setup for Tuesday, 01 Oct 2002 MP 312: Ohmic H-mode rotation profiles Session leader: J. Rice Physics operator: R. Granetz Power Systems as on 1020926035 ECDC overnight in D2 at 2e-4 Torr, stopping by 07:00. Bake at 60 C overnight as well. Set up for possible ECDC in D2 between shots. Run begins at 09:00 and ends at 17:00. Power systems the same as on 1020926035 (0.8 MA, 3.1-5.4 T, lower single null) *** NOTE: *** We will have to begin the run with at least one commutation test to check the repair of yesterday's problem with OH2L. Gas setup: fill B-Top with 6 psi D2 Hybrid enabled (PG4) fill B-side lower with 1 psi Ar Hybrid enabled (PG1) fill B-side upper with 10 psi D2 Hybrid DISABLED (PG2) (for ECDC) fill C-side with 30 psi D2 Hybrid enabled (PG3) leave J-Bottom as is Hybrid DISABLED (PG5) Enable the following gate valves, assuming no vacuum problems: ECE, VUV, DNB ------------------------------------------------------------------------------- RF Setup: All 4 transmitters in Run On by 07:00. ------------------------------------------------------------------------------- Run Plan: Repeat the best ohmic ITB shots from last Thursday's run (1020926), but this time with the argon puffing enabled, in order to get ion rotation and temperature profiles with the Hirex systems. | |
| Oct 1 2002 08:47:54:330AM | Robert Granetz | ECDC was done overnight, as well as a bake at 60 C. Hybrid coldstart done by the engineering group; no errors found Loaded PCS from shot 1000926035 (0.8 MA, 5.4 -> 3.1 -> 4.6 T). Programmed in a 40 ms argon pulse starting at t=0.35 s.. Jim Irby reports that the TCI is out of service today, so I loaded in the NL_ZMETER wire from 1020903020 and adjusted the setting to 0.25, which should give us about the desired density of nl_04=7e19 m-2. We will have to begin the run with at least one commutation test to check the repair of yesterday's problem with OH2L. | |
| Oct 1 2002 10:11:55:617AM | Robert Granetz | There was a 1 hour delay to the start of the run in order to do some more work on the commutation circuits and to repair the TCI. | |
| Oct 1 2002 10:13:25:443AM | 1021001001 | Robert Granetz | Shot 01 -- Test. Charging test of OH2L PFN cap bank. OK. Next shot: go for plasma. Use z-meter for density feedback. |
| Oct 1 2002 11:03:01:193AM | 1021001002 | Robert Granetz | Shot 02 -- Plasma. Disrupted at t=0.97 s ... not sure why, although it was not a VDE. There was bright spot on the J-antenna (wide2 view) at t=0.61 s, without any apparent deleterious effect. Density (with z-meter) was about right (0.8e20 m-2). TCI worked fine. ELMfree H-mode starts at t=0.77 s. Next shot: put NL_04 wire back (remove NL_ZMETER) |
| Oct 1 2002 11:23:15:867AM | 1021001003 | Robert Granetz | Shot 03 -- Plasma. Disrupted at t=1.00 s. Virtually identical to the last shot. No bright spots on J-antenna this time though. ELMfree H-mode starts at t=0.77 s again. Note: I did not actually load the wire change to NL_04 for shot 3. Next shot: reduce argon puff from 40 to 30 ms. NL_04 wire has definitely been loaded for the next shot. |
| Oct 1 2002 11:33:27:397AM | 1021001004 | Robert Granetz | Shot 04 -- Fizzle. Next shot: reduce pre-fill 2 ms and add -10 amps to IC_EF4 to reduce Bz0 a bit. |
| Oct 1 2002 11:53:21:130AM | 1021001005 | Robert Granetz | Shot 05 -- Plasma. Good shot...ramped all the way down. Good ITB up until the RF turns on at t=1.2 s. Prf=3.0 MW. Looks like reducing the argon puff was the right thing to do. ITB shows up on the stored energy and the neutron rate. Next shot: move RXL in a little to try and get an EDA H-mode to start earlier. |
| Oct 1 2002 12:07:32:950PM | 1021001006 | Robert Granetz | Shot 06 -- Plasma. Good shot. H-mode starts earlier (ELMfree), and ITB starts earlier (t=1.0 s), but stops after only a short time. Prf=2.2 MW from D and E only, because JR asked that J-port be turned off. Next shot: move RXU in a little starting earlier in the flattop (to try and get an EDA earlier, and start Btor re-rampup 50 ms earlier. |
| Oct 1 2002 12:27:01:650PM | 1021001007 | Robert Granetz | Shot 07 -- Plasma. Good shot. ITB still is very short-lived. Prf=2.2 MW. Since the RF is working well, John has decided to switch gears and do the MP involving control of the foot of the ITB. The rest of the day will involve RF H-modes, rather than ohmic H-modes. Next shot: change the Btor programming to ramp down only to 4.6 T and stay there. The RF will fire earlier in the shot, in order to get us into H-mode. |
| Oct 1 2002 12:42:20:097PM | 1021001008 | Robert Granetz | Shot 08 -- Plasma. Good shot. Lots of short H-modes, maybe because E-port was faulting alot. Btor=4.67 T (constant during Ip flattop). Current rise is getting slightly slower each shot. Next shot: reduce pre-fill puff by 1 ms, and reduce Btor to 4.47 T. |
| Oct 1 2002 01:05:34:113PM | 1021001009 | Robert Granetz | Shot 09 -- Plasma. Good shot. Still had multiple H-modes. Both D and E had faults, and D then shut off. Btor=4.48 T. Current rise did indeed get a little faster. Next shot: no PCS changes |
| Oct 1 2002 01:12:09:770PM | 1021001010 | Robert Granetz | Shot 10 -- Plasma. Good shot. Lots of short H-modes. Upper triang=0.3. Next shot: reduce RXU by 1 cm starting slightly before t=0.5 s to try and get higher triangularity and EDA H-modes. |
| Oct 1 2002 01:41:39:480PM | 1021001012 | Robert Granetz | Shot 12 -- Plasma. Good shot. H-modes were delayed until t>1.1 s, even though RF was only delayed until t=0.7 s. Upper triang increased up to 0.40! First H-mode was ELMfree, 2nd was EDA. Next shot: increase RXU by 1 cm (halfway between the preceding two shots), and raise the density from nl_04=0.7e20 to 0.8e20 m-2. |
| Oct 1 2002 01:59:33:510PM | 1021001013 | Robert Granetz | Shot 13 -- Plasma. Good shot. But we're still plagued by multiple short ELMfree H-modes, which is not what we want. Current startup is getting faster. Next shot: load segment 2 from shot 11 yesterday (1020930011), which had a good long EDA H-mode. (And constant Btor of 5.4 T). Also add 1 ms to pre-fill puff. |
| Oct 1 2002 02:12:49:903PM | 1021001014 | Robert Granetz | Shot 14 -- Plasma. Good shot. Nice long steady EDA H-mode. No ITB, since the field stayed at 5.4 T. Prf=2.4 MW from D&E, and no faults. Next shot: reduce Btor to 5.1 T by t=0.5 s. |
| Oct 1 2002 02:29:19:797PM | 1021001015 | Robert Granetz | Shot 15 -- Plasma. Good shot. Multiple EDA H-modes, leading to more ELMfree- like H-modes, not due to RF faults. Maybe it's the lower q due to the lower Btor. Prf=2.4 MW. Next shot: add 5 ms to argon puff, and repeat. See if this H-mode behavior repeats itself. |
| Oct 1 2002 02:49:37:023PM | 1021001016 | Robert Granetz | Shot 16 -- Plasma. Good shot. Virtually the same as the previous shot, which is not the long EDA H-mode that we want. Next shot: reduce Btor to 4.8 T |
| Oct 1 2002 02:58:15:397PM | 1021001017 | Robert Granetz | Shot 17 -- Plasma. Good shot. Again, lots of short H-modes. Current startup is slowing down again. Next shot: reduce Ip to 0.6 MA (It's been 0.8 MA all day up until now.) Also reduce pre-fill puff by 1 ms. |
| Oct 1 2002 03:14:27:787PM | 1021001018 | Robert Granetz | Shot 18 -- Plasma. Good shot. 0.6 MA, 4.8 T. Prf=1-2 MW, mostly 1 MW. No H-modes. Next shot: reduce Btor to 4.5 T. |
| Oct 1 2002 03:22:06:350PM | 1021001019 | Robert Granetz | Shot 19 -- Aborted. No-power shot cycle due to EF4 fault during INIT. Next shot: Btor=4.5 T. |
| Oct 1 2002 03:47:30:290PM | 1021001020 | Robert Granetz | Shot 20 -- Plasma. Good shot. Another L-mode shot, even though Prf=1.5 MW. Btor=4.5 T. Next shot: repeat with higher RF power. |
| Oct 1 2002 04:00:04:390PM | 1021001021 | Robert Granetz | Shot 21 -- Plasma. Good shot. Another L-mode shot. Prf=1.5+ MW. Next shot: at the request of the RF operator, reduce the lower triangularity by moving RXL out 2 cm. Also reduce pre-fill puff by 1 ms. |
| Oct 1 2002 04:08:14:720PM | 1021001022 | Robert Granetz | Shot 22 -- Fizzle. Next shot: reduce pre-fill puff another 1 ms. |
| Oct 1 2002 04:28:47:603PM | 1021001023 | Robert Granetz | Shot 23 -- Plasma. Good shot. Another L-mode shot. Next shot: load segment 2 from 1020925007 (0.8 MA, 4.5 T, low triangularities). |
| Oct 1 2002 04:40:23:720PM | 1021001024 | Robert Granetz | Shot 24 -- Plasma. Good shot. Ip=0.8 MA, Btor=4.5 T. Got H-modes back. There's also an ITB, although the central YAG density didn't work on this shot. The GPC is cutoff, however, which is a good ITB indicator. Next shot: reduce Ip to 0.6 MA. Also reduce pre-fill puff another 1 ms. |
| Oct 1 2002 04:58:20:283PM | 1021001025 | Robert Granetz | Shot 25 -- Plasma. Good shot. Ip=0.6 MA, Btor=4.5 T. Three short H-modes, the last of which might have developed an ITB. Prf=1+ MW. Next shot: no PCS changes |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 10:09:17:953AM | Test | Ok | OH2 charging test |
| 2 | 10:41:09:863AM | Plasma | Ok | |
| 3 | 11:05:19:993AM | Plasma | Ok | |
| 4 | 11:23:39:880AM | Plasma | Ok | |
| 5 | 11:37:29:403AM | Plasma | Ok | |
| 6 | 11:55:48:977AM | Plasma | Ok | |
| 7 | 12:09:42:750PM | Plasma | Ok | |
| 8 | 12:29:30:250PM | Plasma | Ok | |
| 9 | 12:44:13:850PM | Plasma | Ok | |
| 10 | 12:59:28:073PM | Plasma | Ok | |
| 11 | 01:14:17:783PM | Plasma | Ok | |
| 12 | 01:29:26:503PM | Plasma | Ok | |
| 13 | 01:43:47:523PM | Plasma | Ok | |
| 14 | 02:01:12:723PM | Plasma | Ok | |
| 15 | 02:16:54:147PM | Plasma | Ok | |
| 16 | 02:32:51:087PM | Plasma | Ok | |
| 17 | 02:49:04:053PM | Plasma | Ok | |
| 18 | 03:04:22:930PM | Plasma | Ok | |
| 19 | 03:19:29:313PM | Plasma | Bad | EF1L SCR Not Conducting Fault |
| 20 | 03:32:20:073PM | Plasma | Ok | |
| 21 | 03:48:59:480PM | Plasma | Ok | |
| 22 | 04:04:17:617PM | Plasma | Ok | |
| 23 | 04:18:01:600PM | Plasma | Ok | |
| 24 | 04:31:42:310PM | Plasma | Ok | |
| 25 | 04:45:49:137PM | Plasma | Ok | |
| 26 | 05:00:04:850PM | Plasma | Ok | |