46,428 research outputs found
Cruise Report 69-S-3: Pelagic fish and trawling survey of Santa Barbara oil spill
(PDF contains 5 pages
AN EDUCATION IN DISTANCE LEARNING: THE CASE OF AGRIBUSINESS 101
A Cal Poly introductory agribusiness class is taught via distance education to a Southern California junior college as part of a pilot project of a USDA grant to increase diversity in agribusiness education. Live, interactive video presents new challenges to on-campus students, distant students and the instructor.distance education, Teaching/Communication/Extension/Profession,
Bostonia. Volume 28
Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs
Stable isotopes, chronology and Bayesian models for the Viking archaeology of north-east Iceland
This paper reviews the results of a long-term research project that used stable isotope analyses (Ī“13C, Ī“15N, Ī“34S) and Bayesian mixing models to better model the chronology for a presumed Viking Age cemetery at HofstaĆ°ir, near Lake MĆ½vatn in north-east Iceland. Ī“13C and radiocarbon dating indicated that many of the individuals consumed a large amount of marine protein, which results in a marine reservoir effect (MRE), making ages older than expected. In addition to the MRE, geological activity in the region has the potential to introduce massive quantities of radioactive ādeadā carbon into the freshwater system, resulting in a very large freshwater reservoir effect (FRE) that can offset radiocarbon ages on the order of a few thousand years. The radiocarbon dates of organisms that derive an unknown proportion of their carbon from both marine and freshwater reservoirs are extremely difficult to ācorrectā, or, more appropriately, model. The research not only highlights the complexities of dealing with multiple reservoirs, but also how important it is to develop models that are temporally and geographically relevant to the site under study. Finally, it shows how this data can be used to inform the development of chronological models for refining the dating for archaeological activity
Who will leave? Oil, migration, and Scottish island youth
Rural communities facing the prospect of rapid energy development consider tradeāoffs between economic benefits and āway of lifeā; as disruption. One of tenācited but unproved benefit of development is increased retention of local youth, who otherwise tend to migrate away. Using survey data from high school students of Scotland\u27s Shetland and Orkney Islands (affected by North Sea oil development), we explore relations between intentions to migrate and individual background, aspirations, and attitudes. Attitudes toward oil development do not predict migration intentions. Instead, migration intentions are predicted by essentially the same variables identified in other studies, in areas where energy development was not occurring. Thus, we found no evidence that oil development fundamentally changed young people\u27s thoughts about leaving
The News You Choose: News Media Preferences Amplify Views on Climate Change
How do choices among information sources reinforce political differences on topics such as climate change? Environmental sociologists have observed large-scale and long-term impacts from news media and think-tank reports, while experimental science-communication studies detect more immediate effects from variations in supplied information. Applying generalized structural equation modeling to recent survey data, previous work is extended to show that political ideology, education and their interaction predict news media information choices in much the same way they predict opinions about climate change itself. Consequently, media information sources serve as intervening variables that can reinforce and, through their own independent effects, amplify existing beliefs about climate change. Results provide empirical support for selective exposure and biased assimilation as mechanisms widening political divisions on climate change in the United States. The findings fit with the reinforcing spirals framework suggesting partisan media strengthens climate change beliefs which then influences subsequent use of media
Direct EIT Reconstructions of Complex Admittivities on a Chest-Shaped Domain in 2-D
Electrical impedance tomography (EIT) is a medical imaging technique in which current is applied on electrodes on the surface of the body, the resulting voltage is measured, and an inverse problem is solved to recover the conductivity and/or permittivity in the interior. Images are then formed from the reconstructed conductivity and permittivity distributions. In the 2-D geometry, EIT is clinically useful for chest imaging. In this work, an implementation of a D-bar method for complex admittivities on a general 2-D domain is presented. In particular, reconstructions are computed on a chest-shaped domain for several realistic phantoms including a simulated pneumothorax, hyperinflation, and pleural effusion. The method demonstrates robustness in the presence of noise. Reconstructions from trigonometric and pairwise current injection patterns are included
Preliminary design of an auxiliary power unit for the space shuttle. Volume 4: Selected system supporting studies
Selected system supporting analyses in conjunction with the preliminary design of an auxiliary power unit (APU) for the space shuttle are presented. Both steady state and transient auxiliary power unit performance, based on digital computer programs, were examined. The selected APU provides up to 400 horsepower out of the gearbox, weighs 227 pounds, and requires 2 pounds per shaft horsepower hour of propellants
Preliminary design of an auxiliary power unit for the space shuttle. Volume 5: Selected system cycle performance data
Detailed cycle steady-state performance data are presented for the final auxiliary power unit (APU) system configuration. The selection configuration is a hydrogen-oxygen APU incorporating a recuperator to utilize the exhaust energy and using the cycle hydrogen flow as a means of cooling the component heat loads. The data are given in the form of computer printouts and provide the following: (1) verification of the adequacy of the design to meet the problem statement for steady-state performance; (2) overall system performance data for the vehicle system analyst to determine propellant consumption and hydraulic fluid temperature as a function for varying mission profiles, propellant inlet conditions, etc.; and (3) detailed component performance and cycle state point data to show what is happening in the cycle as a function of the external forcing functions
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