2,976 research outputs found
Large-scale Reservoir Simulations on IBM Blue Gene/Q
This paper presents our work on simulation of large-scale reservoir models on
IBM Blue Gene/Q and studying the scalability of our parallel reservoir
simulators. An in-house black oil simulator has been implemented. It uses MPI
for communication and is capable of simulating reservoir models with hundreds
of millions of grid cells. Benchmarks show that our parallel simulator are
thousands of times faster than sequential simulators that designed for
workstations and personal computers, and the simulator has excellent
scalability
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Towards outcomes-based assessment:an unfinished story of triangulation and transformation
Over the past ten years Higher Education in the United Kingdom (UK) has changed in many ways, mainly influenced by the recommendations of the Dearing Report (published in 1997). One paragraph in the report instigated a fundamental reorientation in the articulation within higher education of teaching, learning and assessment in terms of learning outcomes. Subsequent quality assurance initiatives have reinforced this approach. For the last ten years, the Centre for Outcomes-Based Education (COBE) in the UK Open University (UK OU) has been leading the transformation of the OU curriculum into an outcomes-based approach. The key to this process has been the
'triangulation' between curriculum, staff and student development. Throughout the process, our main concern has been to describe, develop and implement an appropriate way to assess learning outcomes both at course and award level. This paper re-views the process and poses some fundamental questions about an outcomes-based approach to the design and delivery of the curriculum and to the development of staff and students
The effect of opening up ANWR to drilling on the current price of oil
The Effect of Opening up ANWR to Drilling on the Current Price of Oil R. Morris Coats and Gary M. PecquetEveryone knows that oil discovered today, perhaps in the Alaskan National Wildlife Refuge (ANWR), has no effect on prices until that oil hits the market. For instance, on its website, the Democratic Policy Committee, (http://democrats.senate.gov/~dpc/pubs/107-1-72.html) states that “it will require seven to twelve years from approval before there is any oil production from the ANWR area. Therefore, production in ANWR will have no impact on current or short-term gasoline and oil supplies and prices.” While this is something that everyone seems to know, it is a case that the theory held by everyone just happens to be wrong. Since future prices are expected to be lower, future profits are also lower, so the value of oil not produced now, but held for future sales, is lower, making it more profitable to go ahead and produce and sell now instead of waiting for future profits. Using oil now reduces the amount of oil available for the future, which involves the opportunity cost of forgone future profits, which are sometime called the marginal user costs or scarcity rents. In this paper, we use simple two-period models to show that if an amount of newly discovered oil is significant enough to reduce prices in the future, any drop in future prices reduces the future profitability of oil, reducing the marginal user costs of oil now. That reduction in the marginal user costs reduces the current price of oil just as if there were a reduction in the marginal costs of extracting oil now. We explore the effects of the reduction in marginal user costs in the competitive or price-taker case as well as the price-searcher case, where a monopolist or dominant supplier responds to a substantial discovery by another seller, but where the discovery will not contribute to production for some years to come. In both cases, we find that oil that is expected to reach the market at some time in the future has an immediate impact on oil prices. Topic Area: Q4 EnergyANWR; resource discovery; timing of price impact; speculation
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Physiological monitoring in the complex multimorbid heart failure patient - Conclusions.
Comorbidities are increasingly recognized as crucial components of the heart failure syndrome. Main specific challenges are polypharmacy, poor adherence to treatments, psychological aspects, and the need of monitoring after discharge. The chronic multimorbid patient therefore represents a specific heart failure phenotype that needs an appropriate and continuous management over time. This supplement issue covers the key points of a series of meeting coordinated by the Heart Failure Association of the European Society of Cardiology (ESC), that have discussed the issues surrounding the effective monitoring of our ever more complex and multimorbid heart failure patients. Here, we present an overview of the complex issues from a healthcare delivery perspective
“Extermination or Removal”: The Knights of the Forest and Ethnic Cleansing in Early Minnesota
The Knights of the Forest was an 1863 secret society that formed in Mankato, MN, during the aftermath of the U.S.-Dakota War. They took an oath to advocate for the banishment of “all Indians” from the state of Minnesota. But newspaper articles written by and about four members show that the organization was only concerned with the exile of the Ho-Chunk people, who had not participated in the U.S.-Dakota War. In the winter of 1862-1863, settlers in the Mankato region pressured the federal government for Ho-Chunk removal under the threat of extermination of the Ho-Chunk people. Their reservation had comprised the majority of prime farmland in Blue Earth County just southeast of Mankato since 1855. The Knights of the Forest sent armed men to surround the Ho-Chunk land and shoot anyone who crossed the line. Once the Ho-Chunk were forced from the county in May of 1863, the secret society ceased to exist. Hundreds of Ho-Chunk people died because of their removal from Minnesota. Conditions at Crow Creek Reservation in South Dakota were so desolate many left to Omaha or back to their Wisconsin homeland within months. Meanwhile, new settlers moved onto their former southwestern Minnesota reservation, and Blue Earth County experienced its earliest economic expansion at the expense of the Ho-Chunk Nation
Elemol and amyris oil repel the ticks Ixodes scapularis and Amblyomma americanum (Acari: Ixodidae) in laboratory bioassays.
The essential oil from Amyris balsamifera (Rutaceae) and elemol, a principal constituent of the essential oil of Osage orange, Maclura pomifera (Moraceae) were evaluated in in vitro and in vivo laboratory bioassays for repellent activity against host-seeking nymphs of the blacklegged tick,Ixodes scapularis, and the lone star tick, Amblyomma americanum. Both bioassays took advantage of the tendency of these host-seeking ticks to climb slender vertical surfaces. In one bioassay, the central portion of a vertical strip of filter paper was treated with test solution and ticks placed or allowed to crawl onto the untreated lower portion. In the other bioassay, a strip of organdy cloth treated with test solution was doubly wrapped (treatment on outer layer) around the middle phalanx of a forefinger and ticks released on the fingertip. Both amyris oil and elemol were repellent to both species of ticks. Elemol did not differ significantly in effectiveness against A. americanum from the widely used repellent deet. At 2 and 4 h after application to filter paper, 827 μg amyris oil/cm2 paper repelled 80 and 55%, respectively, of A. americanum nymphs. Ixodes scapularis was repelled by lower concentrations of amyris oil and elemol than A. americanum
Adventitial ablation technique that permits the assessment of adventitial-dependent contribution to microvascular contractile function
Resistance arteries have been implicated as major contributing factor in the sequela of disease conditions such as hypertension and diabetes and as such are a major focus of cardiovascular research. The paracrine influence of the intimal endothelial layer of resistance arteries is well established. Considering the growing body of evidence substantiating a functionally relevant vascular adventitia in this present study we have established a technique which permits determination of the functional influence of the adventitial layer on resistance artery tone. Isolating adventitial-dependent function, analogous to isolating endothelial function, has potentially significant implication for studying the as yet unexplored role of the microvascular adventitial layer in modulating acute vascular contractile function
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