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The sperm whale has adapted to cope with drastic pressure changes when diving. The flexible ribcage allows lung collapse, reducing nitrogen intake, and metabolism can decrease to conserve oxygen.[23][24] Myoglobin, which stores oxygen in muscle tissue, is much more abundant than in terrestrial animals.[25] The blood has a high red blood cell density, which contain oxygen-carrying hemoglobin. The oxygenated blood can be directed towards the brain and other essential organs only when oxygen levels deplete.[26][27][28] The spermaceti organ may also play a role by adjusting buoyancy (see below).[29]
While sperm whales are well adapted to diving, repeated dives to great depths have long term effects. Bones show pitting that signals decompression sickness in humans. Older skeletons showed the most extensive pitting, whereas calves showed no damage. This damage may indicate that sperm whales are susceptible to decompression sickness, and sudden surfacing could be lethal to them.[30]
Between dives, the sperm whale surfaces to breathe for about eight minutes before again diving.[4] Odontoceti (toothed whales) breathe air at the surface through a single, S-shaped blowhole. Sperm whales spout (breathe) 3–5 times per minute at rest, increasing to 6–7 times per minute after a dive. The blow is a noisy, single stream that rises up to 15 metres (49 ft) above the surface and points forward and left at a 45° angle. On average, females and juveniles blow every 12.5 seconds before dives, while large males blow every 17.5 seconds before dives.[31]
The spermaceti organs may help adjust the whale's buoyancy. Before diving, cold water enters the organ and the wax solidifies.[29][37] The increase in specific density generates a down force of about 40 kilograms (88 lb)[clarification needed] and allows the whale to dive with less effort. During the hunt, oxygen consumption produces heat and melts the spermaceti, increasing its buoyancy, enabling easy surfacing.[38]
Herman Melville's Moby Dick suggests that the "case" containing the spermaceti evolved as a kind of battering ram for use in fights between males.[39] This hypothesis is consistent with the well-documented sinking of the ships Essex and Ann Alexander by attackers estimated to weigh only one-fifth as much as the ships.[40]
Another possibility is that the case aids echolocation (see melon).[5] The organ's variable shape narrows or spreads the sound.[41]
The sperm whale has two nostrils. An external nostril forms the blow hole, and an internal nostril presses against the bag-like spermaceti container.[5] The male's spermaceti organ is much larger than the female's. This may be a case of sexual selection, enabling males to compete for females using sound displays.[42]
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| 큐이름 | Wall Clock Limit (시간) |
작업 실행 노드 | 작업별 CPU수 |
Priority | SU Charge Rate |
비 고 |
|
normal |
48 |
tachyon001-188 |
17-1536 |
normal |
1 |
|
| long | 168 | tachyon001-188 | 1-128 | Low | 1 | Long running 작업 |
| strategy | TBD | tachyon001-188 | 32-3008 | High | 1 | Grand Challenge 작업 |
| Option | Result |
| no option | 명령을 실행한 사용자 job의 상세 list를 보여줌 |
| -f | 명령을 실행한 사용자에 대한 queue와 job의 상세 리스트를 보여줌 |
| -u user_id | 명시한 user_id에 대한 상태를 보여줌. ?u "*"는 전체 사용자의 상태를 보여줌. 주로 ?f 옵션과 함께 쓰임. |
| -r | Job의 resource requirement를 display |
| -ext | Job의 Extended information을 display |
| -j <iobid> | Pending/running job에 대한 information을 보여줌 |
| -t | Job의 subtask에 대한 추가 정보 display |
※ 작업 스크립트 옵션 리스트 |
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