94 research outputs found
Surface drifting floats serial numbers 327-352 March 1976: tables of times and positions. Diagrams showing trajectories and components of displacement
No full textExploring beneath the PIG Ice Shelf with the Autosub3 AUV
No full textOn 31st January 2009, two numbers: “range and
bearing” flashing up on a laptop screen, indicated that Autosub3
had returned from its last mission beneath the Pine Island Glacier
(PIG) Ice Shelf in the Western Antarctic. The Autosub technical
team from NOCS, Southampton, onboard the US ice breaker
Nathanial B Palmer breathed a collective sigh of relief. Any
significant technical failure would have resulted in total loss of the
multi million Euro Autonomous Underwater Vehicle with no hope
of recovery from 60 km into the ice shelf cavity. This was the last
of six successful missions to investigate the shape the ice shelf, the
sea bed bathymetry, the currents and the physical oceanography
within the ice cavity. Each are vital to understanding the
interaction between the sea water and the ice shelf, and
quantifying whether the melting rate is changing. During the
cruise, Autosub3 had run beneath the ice for almost 4 days and
for 510 km.
Autosub3 had been exploring the Pine Island Glacier, a floating
extension of the West Antarctic ice sheet, as part of an
international team effort lead by Dr Adrian Jenkins of the British
Antarctic Survey and Dr Stanley Jacobs of the Lamont-Doherty
Earth Observatory, New York. Autosub3 was launched from the
Nathaniel B Palmer, an American icebreaker, as part of the two
month cruise to investigate the oceanography, biology and
glaciology of the Southern Amundsen Sea.
This paper will concentrate on the technical aspects of the
Autosub3 vehicle and its missions under the PIG, and seek to
answer a number of questions: How did the AUV successfully
dead reckon navigate for over 24 hours, and return accurately to
the rendezvous point? How did we cope with the possibility of ice
bergs or sea ice drifting over the recovery position ? How did
Autosub3 (almost always) avoid collision with the jagged ice shelf
above, or the unknown depths of the seabed? How did we
communicate with the vehicle at the start and the end of missions?
How did we manage risk, and prior to the cruise, what
modifications and testing did we apply to the AUV to improve the
overall reliability? What measures did we take during the cruise
to further improve our chances of a successful outcome ?
The paper will outline the history of the use of AUVs for polar
science. Results from the recent cruise will be presented showing
the actual mission tracks, with the echo sounder isonified ice draft
and seabed. Not all went completely to plan: the paper will also
describe the events of Autosub’s close scrape on its 4th mission
under the PIG.
This work was fun
A randomized controlled trial of an appearance-based dietary intervention
No full textObjective: Inadequate fruit and vegetable consumption precipitates preventable morbidity and mortality. The efficacy of an appearance-based dietary intervention was investigated, which illustrates the beneficial effect that fruit and vegetable consumption has on skin appearance. Methods: Participants were randomly allocated to three groups receiving information-only or a generic or own-face appearance-based intervention. Diet was recorded at baseline and 10 weekly follow-ups. Participants in the generic and own-face intervention groups witnessed on-screen stimuli and received printed photographic materials to illustrate the beneficial effect of fruit and vegetable consumption on skin color. Results: Controlling for baseline diet, a significant effect of intervention group was found on self-reported fruit and vegetable intake among 46 completers who were free of medical and personal reasons preventing diet change. The own-face appearance-based intervention group reported a significant, sustained improvement in fruit and vegetable consumption whereas the information-only and generic appearance-based intervention groups reported no significant dietary changes. Conclusions: Seeing the potential benefits of fruit and vegetable consumption on own skin color may motivate dietary improvement.Peer reviewe
An investigation of avoidance by Antarctic krill of RRS "James Clark Ross" using the Autosub-2 autonomous underwater vehicle
No full textThe autonomous underwater vehicle (AUV) Autosub-2 was deployed on eight missions ahead of RRS James Clark Ross in the northern Weddell Sea and in the Bransfield Strait, Southern Ocean, to assess avoidance of the research vessel by Antarctic krill Euphausia superba. The AUV was equipped with the same type of scientific echosounder as the research vessel (Simrad EK500 operating at 38 and 120 kHz) and measured the density of krill along transect acoustically (g m-2 wet mass) prior to the ship's arrival. We hypothesised that if krill avoided the ship, perhaps in response to radiated noise, then the ship should detect less krill than the AUV which is known to have much lower noise levels than the ship. We were unable to detect any significant difference between the density of krill detected by the ship or the AUV, either at the transect level or at finer scales within transects. We conclude, therefore, that avoidance by krill of RRS James Clark Ross will not significantly bias acoustic estimates of krill abundance by this vessel
Multidisciplinary ocean science applications of an AUV: the AUTOSUB science missions programme
No full textThe Eskimo book of knowledge
No full textThe Eskimo Book of KnowledgeThe British Empire to which you belong. King George and Queen Mary who are your rulers -- How the empire of the King and Queen was formed -- Canada and the Company -- The laws of Canada and Newfoundland -- The men of God -- Health. The change that has come to the Innuit -- Health -- The power of food in the body -- The trail towards health -- For Innuit wives -- The building and care of houses -- Work. The nature of work among all men -- Trapping and care of skins -- The example of white workers -- Care in work -- Conclusion. The pledge of the company to the InnuitEnglish and Inuktitut on facing pages ; added title page in Inuktitu
Skeletal muscle purine nucleotide levels in normal and phosphorylase kinase deficient mice
No full textThe use of computational fluid dynamics to assess the hull resistance of concept autonomous underwater vehicles
No full textAutonomous Underwater Vehicles (AUV’s) provide an important tool for collecting detailed scientific information from the oceans depths. The hull resistance of an AUV is an important factor in determining the powering requirements and range of the vehicle. This paper discusses the use of Computational Fluid Dynamics (CFD) to determine the hull resistance of three existing AUV’s, of differing shape and size. The predictions are compared with available experimental data and good agreement found. This work has demonstrated that with use of suitable shape parameterisation it is possible to carry out concept design evaluation using a RANS flow solver
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