415 research outputs found
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EOR as sequestration: Geoscience perspective
CO2 Enhanced Oil Recovery (EOR) has a development and operational history several decades longer than geologic sequestration of CO2 designed to benefit the atmosphere and provides much of the experience on which confidence in the newer technology is based. With modest increases in surveillance and accounting, future CO2 EOR using anthropogenic CO2 (CO2-A) captured to decrease atmospheric emissions can be used as part of a sequestration program.Bureau of Economic Geolog
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Operation of a Public Geologic Core and Sample Repository in Houston, Texas
In the spring of 2002, the Department of Energy (DOE) allocated an initial 1-year grant to the Bureau of Economic Geology (BEG) at The University of Texas at Austin (UT). This grant covered the operational expenses for one year of a world-class core and cuttings facility located in Houston, Texas, which was generously donated to BEG by BP America. The DOE investment totaled 75,000 contribution from UT. These funds provided crucial support in the first year, greatly supplemented by BP's donation of 30,000 for the month of May 2003. A 5-year plan is underway to establish a permanent endowment to sustain the facility indefinitely, and progress is on track according to schedule. Named the Houston Research Center, this facility serves as an exemplary model of collaboration between the Federal government, universities, and private entities to achieve national objectives.
This report outlines the activities supported by the initial DOE grant during the first 13 months of operation and offers insights into the facility's activities and requirements for its second year of operation.Bureau of Economic Geolog
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Economic analysis for a national ultra-deepwater and unconventional oil and gas supply research fund
This study provides an analysis of future incremental Federal lands and U.S. oil and gas production, and its associated economic benefits, that could be achieved through the establishment of a supply research fund. The supply research fund is based on H.R. 6, Subtitle E - Fossil Energy, Part 1, Sec. 21501(b) and Part 3 - Ultra-deepwater and Unconventional Natural Gas and Other Petroleum Resources, submitted to the 108th U.S. Congress. The legislation provides for the establishment of a supply research fund from a percentage of the amount of royalties, rents, and bonuses derived from Federal onshore and offshore oil and gas leases issued under the Outer Continental Shelf Lands Act and the Mineral Leasing Act for each of fiscal years 2003 through 2010. This report is an update to a previous report, "Benefit/cost analysis of GRI's gas supply research initiative" (Kim and others, 2000), which contains an analysis of the benefits and costs of a gas supply research fund.
The value of technology developed and advanced through the supply research fund was examined in terms of resulting incremental production. Incremental production was expected to be greatest among complex and new resource areas such as the deepwater offshore and unconventionals. Federal lands' incremental oil and gas production forecast by technological advancements achieved by the supply research fund during the period from 2003 through 2025 was calculated as 4,202 million bbl and 28.79 Tcf, respectively. The resulting incremental production and royalty revenue were 28,749 million, respectively.Bureau of Economic Geolog
Perspectives on ‘novel’ techniques for designing age-friendly homes and neighborhoods with older adults
Worldwide, growth in the older population creates a pressing need to develop supportive environments that enhance quality of life as people age. Too often, built environments present barriers and challenges to older adults that compromise independent living and adversely affect health and life outcomes. Designing homes, buildings, and neighborhoods with older adults, through exercises in participatory or co-design, could help ensure that environments are better able to facilitate healthy aging. However, while it is potentially advantageous to involve this age group in environmental design decisions, doing so can be difficult. Analysis of and guidance on effective ways to involve older adults in these activities could make the challenge easier. With this aim in mind, this article provides critical perspectives on eight “less traditional” engagement techniques—walking interviews, photovoice, photo-elicitation, Talking Mats®, participatory mapping, drawing, model-making, and the “Design Fair”. Insights into the strengths and limitations of these techniques, gained from observation of their use in participatory design activities, as well as feedback collected from older co-design participants, are presented. The article concludes by offering a number of practical recommendations for those interested in designing age-friendly homes and neighborhoods with older people
Redshift space 21 cm power spectra from reionization
We construct a simple but self-consistent analytic ionization model for rapid
exploration of 21cm power spectrum observables in redshift space. It is fully
described by the average ionization fraction and HII patch size
and has the flexibility to accommodate various reionization scenarios. The
model associates ionization regions with dark matter halos of the number
density required to recover and treats redshift space distortions
self-consistently with the virial velocity of such halos. Based on this model,
we study the line-of-sight structures in the brightness fluctuations since they
are the most immune to foreground contamination. We explore the degeneracy
between the HII patch size and nonlinear redshift space distortion in the one
dimensional power spectrum. We also discuss the limitations experimental
frequency and angular resolutions place on their distinguishability. Angular
resolution dilutes even the radial signal and will be a serious limitation for
resolving small bubbles before the end of reionization. Nonlinear redshift
space distortions suggest that a resolution of order 1 -- 10\arcsec and a
frequency resolution of 10kHz will ultimately be desirable to extract the full
information in the radial field at . First generation instruments
such as LOFAR and MWA can potentially measure radial HII patches of a few
comoving Mpc and larger at the end of reionization and are unlikely to be
affected by nonlinear redshift space distortions.Comment: 13 pages, 10 figures. Revised version. Includes minor changes. Adds
appendix on accomodating a distribution of radii for the HII regions.
Accepted for publication in Ap
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Operation of a Public Geologic Core and Sample Repository in Houstion, Texas
The Bureau of Economic Geology's Houston Research Center (HRC) is well established as a premier regional research center for geologic research serving not only Houston, but geoscientists from around Texas, the U. S., and even the world. As reported in the FY05 and FY06 technical progress reports to the DOE, the HRC provides a state-of-the-art core viewing facility, two fully equipped conference rooms, and a comprehensive technical library, all available for public use. In addition, the HRC currently now houses over 725,000 boxes of rock material (as of January 2008), and has space to hold approximately 300,000 more boxes. Use of the facility has remained strong; the number of patrons averaged over 100 per month from June 1, 2006 to October 2007, and 90,000 boxes of core were donated to, and received by, the HRC during this time. Usage is a combination of individuals describing core, groups of geoscientists holding seminars and workshops, and various industry and government-funded groups holding short courses, workshops, and seminars. These numbers are in addition to the numerous daily requests from patrons desiring to have rock material shipped offsite to their own offices. The BEG/HRC secured several substantial donations of rock materials and cash totaling approximately 2.2 million from Shea Homes (heritage Unocal rock material),Chevron and others this operating year, the HRC endowment now totals 10 million in endowment; after several years of operation we realize we require an 3 million to fully fund the endowment. To meet these goals in the 2007 operating year will require DOE support for the fifth and final year. DOW support will allow for {approx}1 million, and set the plan way back. We recognize that DOE budgets for oil and gas research, against best efforts, have been cut substantially this year. Any support available for HRC operation, during continuing resolution or otherwise, would have a very positive impact on this critical final year of the original business plan
Evaluation of Joint Space Width and Narrowing After Isolated Partial Medial Meniscectomy for Degenerative Medial Meniscus Tears
BACKGROUND: Few studies have evaluated the effect of existing articular cartilage damage and sex on joint space measurements after isolated degenerative medial meniscus tears.
PURPOSE: To determine what factors affected joint space width and narrowing in patients after removal of isolated degenerative medial meniscus tears.
STUDY DESIGN: Cohort study; Level of evidence, 2.
METHODS: A total of 62 patients (15 women and 47 men) with all ligaments intact, no previous surgery to either knee, and an isolated degenerative medial meniscus tear removed in 1 knee were examined. The mean age at examination was 58.2 years at a mean follow-up of 9.4 years (range, 4-20 years). Subjective results were obtained with the International Knee Documentation Committee (IKDC) knee survey. Radiographs were taken using 45° weightbearing posteroanterior views. Midpoint and perceived minimum joint space width of the medial and lateral compartments of both knees were measured to the nearest 0.1 mm by 2 observers at different times, and they were blinded as to the previous measurements (Pearson intra- and interclass correlations, >0.93). Joint space narrowing was found by calculating the difference in joint space width between knees. Percentage of normal joint space loss was calculated by dividing joint space narrowing by the joint space width in the contralateral knee. Other factors considered were patient sex and Outerbridge grading of articular cartilage.
RESULTS: Women had a mean 1.5 mm less normal joint space width than men in the involved and noninvolved knees (P 50% of the normal joint space as measured in the noninjured knee (P = .016). The mean IKDC total score was 66.1 points for women, which was statistically significantly lower than the mean of 82.7 points for men (P < .01).
CONCLUSION: Patients undergoing partial medial meniscectomy have greater joint space narrowing and lower subjective scores after surgery if they also have existing Outerbridge grade 3-4 damage. Women have less normal joint space than men, and more women than men experience >50% joint space narrowing after surgery
A Performance Comparison of a Technical Trading System with ARIMA and VAR Models for Soybean Complex Prices
Both technical trading systems and standard economic time series models are based upon the assumption that current market prices are not independent of past market behavior. This study examines the relative performance of a Channel (CHL) technical trading system with an Autoregressive Integrated Moving Average (ARIMA) model and a Vector Autoregressive (VAR) model in forecasting soybean, soybean meal, and soybean oil prices over the period January 1984-June 1988. ARIMA and VAR models are developed over the time period January 1974-December 1983 and then are used to forecast out-of-sample from January 1984 through June 1988. The CHL trading signals and out-of-sample two month ahead forecasts from the ARIMA and VAR models are used to take positions in the futures markets. The resulting trading returns are evaluated to determine the relative economic performance of the models within the soybean complex. Of these models, the CHL technical trading system exhibits consistent trading returns across the soybean complex. Furthermore, the CHL technical trading system is robust across the two subperiods of the out-of-sample period, one of which is characterized by rising commodity prices and the other by declining commodity prices. These results suggest that in the short run, regularities within a single price series can be used to forecast prices within the soybean complex. Further, technical trading system prove more useful in utilizing such regularities for forecasting than the autoregressive or moving average processes found in either ARIMA or VAR modeling techniques
The Drought Monitor
There is a need for improved drought monitoring and assessment methods in the United States. Drought is the most costly natural disaster [Federal Emergency Management Agancy (FEMA 1995; Wilhite 2000)], but it is often neglected by developers of assessment and forecast products. Drought is more nebulous than other disasters and does not lend itself to traditional assessments or forecast methods. Its relatively slow onset and the complexity of its impacts are reasons for the new assessment methodology. Improvements in drought monitoring and forecasting techniques will allow for better preparation, lead to better management practices, and reduce the vulnerability of society to drought and its subsequent impacts.
The Drought Monitor (additional information available online at http://drought.unl/edu/dm) was created with the goal of tracking and displaying the magnitude and spatial extent of drought and its impacts across the United States. The Drought Monitor is produced weekly and classifies drought severity into four major categories, with a fifth category threshold assigned to locations on a map are determined from a number of indicators, or tools, blended with subjective interpretation
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Operation of a Public Geologic Core and Sample Repository in Houstion, Texas
The Bureau of Economic Geology's Houston Research Center (HRC) is well established as a premier regional research center for geologic research serving not only Houston, but geoscientists from around Texas, the US, and even the world. As reported in the 2004-2005 technical progress report to the DOE, the HRC provides a state-of-the-art core viewing facility, two fully equipped conference rooms, and a comprehensive technical library, all available for public use. In addition, the HRC currently now houses over 600,000 boxes of rock material, and has space to hold approximately 300,000 more boxes. Use of the facility has remained strong during this fourth year of operation; the number of patrons averaged nearly 150 per month from June 1, to 2005 May 31, 2006. This usage is a combination of individuals describing core, groups of geoscientists holding seminars and workshops, and various industry and government-funded groups holding short courses, workshops, and seminars. These numbers are in addition to the numerous daily requests from patrons desiring to have rock material shipped offsite to their own offices. The BEG/HRC secured several substantial donations of rock materials and cash totaling approximately 2.2 million from Shea Homes (heritage Unocal rock material), Chevron and others this operating year, the HRC endowment now totals 10 million in endowment; after several years of operation we realize we require an 3 million to fully fund the endowment. To meet these goals in the 2006-2007 operating year will require DOE support for the fifth and final year. DOE support will allow for {approx}1 million, and set the plan way back. We recognize that DOE budgets for oil and gas research, against best efforts, have been cut substantially this year. Any support available for HRC operation, during continuing resolution or otherwise, would have a very positive impact on this critical final year of the original business plan
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