609 research outputs found

    Climate dynamics experiments using a GCM simulations

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    The study of surface-atmosphere interactions has begun with studies of the effect of altering the ocean and land boundaries. A ten year simulation of global climate using observed sea surface temperature anomalies has begun using the NCAR Community Climate Model (CCM1). The results for low resolution (R15) were computed for the first 8 years of the simulation and compared with the observed surface temperatures and the MSU (Microwave Sounding Unit) observations of tropospheric temperature. A simulation at higher resolution (T42) was done to ascertain the effect of interactive soil hydrology on the system response to an El Nino sea surface temperature perturbation. Initial analysis of this simulations was completed

    Benchmarking of Flexibility and Needs - 2004

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    ITRC interviewed irrigation district personnel from 25 agricultural districts in eastern Washington, northern Idaho and western Montana. Data were analyzed to determine the degree of water delivery flexibility provided to farmers and the extent of existing and planned district modernization. This is the fourth such report the Irrigation Training and Research Center (ITRC) has published for irrigation districts in the western US. The first two evaluations were conducted on behalf of the Mid-Pacific Region of the US Bureau of Reclamation (USBR) and included California irrigation districts that had long-term federal contracts. The third report was prepared on behalf of the California Department of Water Resources (DWR) and did not include irrigation districts with long-term federal contracts. The first three evaluations were conducted in 1996, 2000 and 2002, respectively. All three reports can be downloaded from the ITRC’s Reports web page (http://www.itrc.org/reports/reportsindex.html). This report was prepared on behalf of the USBR Yakima Office of Water Conservation, Upper Columbia Area of the Pacific Northwest Region and includes districts that receive at least some water from federal facilities. The interview process identified a strong perceived need by the districts for more direct technical assistance and training. This perceived need is greater than what ITRC has seen in California irrigation districts. These needs varied by district and region. In addition to general support, some districts acknowledged interest in small, specialized training efforts customized for single or small groups of districts at local facilities. Interest is especially high for information about automation and Supervisory Control and Data Acquisition (SCADA) systems. The data also indicated that more Rapid Appraisal Process (RAP) visits are needed to determine possible physical and operational improvements (modernization and efficiency) for districts to accommodate the ever-changing needs of their consumers and the environment. Direct technical assistance to individual districts has been and will continue to be a key element of continuing success in modernization. Other key items include: Many of the districts, and their farmers, are heavily dependent upon electric power to convey and distribute irrigation water. Presently, the power rates are lower than in other areas of the West. Irrigation district personnel, on the average, consider on-farm water usage/conservation to be beyond their scope of responsibility. This indicates that the “Bridging the Headgate” initiative by USBR and others may need more effort. Although 24 of the 25 districts provide water on at least an “arranged” basis, there is still room for improvement of the water delivery flexibility provided to farmers. The overall Flexibility Index was 11.5 (max. possible = 15; min. possible = 3). This compares with an overall Flexibility Index of 10.9 for sixteen non-Federal irrigation districts ranked by ITRC in 2002, and an Index of 12.9 for 58 Federal irrigation districts ranked by ITRC in 2000. Since 1995 the irrigation districts have made numerous improvements, including both software and hardware. This report summarizes the results and provides brief comments on various aspects of those results

    Global water cycle

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    The primary objective is to determine the scope and interactions of the global water cycle with all components of the Earth system and to understand how it stimulates and regulates changes on both global and regional scales. The following subject areas are covered: (1) water vapor variability; (2) multi-phase water analysis; (3) diabatic heating; (4) MSU (Microwave Sounding Unit) temperature analysis; (5) Optimal precipitation and streamflow analysis; (6) CCM (Community Climate Model) hydrological cycle; (7) CCM1 climate sensitivity to lower boundary forcing; and (8) mesoscale modeling of atmosphere/surface interaction

    Examining \u3cem\u3eDSM\u3c/em\u3e Criteria for Trichotillomania in A Dimensional Framework: Implications for \u3cem\u3eDSM-5\u3c/em\u3e And Diagnostic Practice

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    Background: Diagnosis of Trichotillomania (TTM) requires meeting several criteria that aim to embody the core pathology of the disorder. These criteria are traditionally interpreted monothetically, in that they are all equally necessary for diagnosis. Alternatively, a dimensional conceptualization of psychopathology allows for examination of the relatedness of each criterion to the TTM latent continuum. Objectives: First, to examine the ability of recently removed criteria (B and C) to identify the latent dimensions of TTM psychopathology, such that they discriminate between individuals with low and high degrees of hair pulling severity. Second, to determine the impact of removing criteria B and C on the information content of remaining diagnostic criteria. Third, to determine the psychometric properties of remaining TTM diagnostic criteria that remain largely unchanged in DSM-5; that is, whether they measure distinct or overlapping levels of TTM psychopathology. Fourth, to determine whether information content derived from diagnostic criteria aid in the prediction of disease trajectory (i.e., can relapse propensity be predicted from criteria endorsement patterns). Method: Statistics derived from Item Response Theory were used to examine diagnostic criteria endorsement in 91 adults with TTM who underwent psychotherapy. Results: The removal of two criteria in DSM-5 and psychometric validity of remaining criteria was supported. Additionally, individual trait parameters were used to predict treatment progress, uncovering predictive power where none previously existed. Conclusions: Diagnostic criteria for TTM should be examined in dimensional models, which allow for nuanced and sensitive measurement of core symptomology in treatment contexts

    Mandated data archiving greatly improves access to research data

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    The data underlying scientific papers should be accessible to researchers both now and in the future, but how best can we ensure that these data are available? Here we examine the effectiveness of four approaches to data archiving: no stated archiving policy, recommending (but not requiring) archiving, and two versions of mandating data deposition at acceptance. We control for differences between data types by trying to obtain data from papers that use a single, widespread population genetic analysis, STRUCTURE. At one extreme, we found that mandated data archiving policies that require the inclusion of a data availability statement in the manuscript improve the odds of finding the data online almost a thousand-fold compared to having no policy. However, archiving rates at journals with less stringent policies were only very slightly higher than those with no policy at all. At one extreme, we found that mandated data archiving policies that require the inclusion of a data availability statement in the manuscript improve the odds of finding the data online almost a thousand fold compared to having no policy. However, archiving rates at journals with less stringent policies were only very slightly higher than those with no policy at all. We also assessed the effectiveness of asking for data directly from authors and obtained over half of the requested datasets, albeit with about 8 days delay and some disagreement with authors. Given the long term benefits of data accessibility to the academic community, we believe that journal based mandatory data archiving policies and mandatory data availability statements should be more widely adopted

    Parallel ODETLAP for terrain compression and reconstruction

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    We introduce a parallel approximation of an Over-determined Laplacian Partial Differential Equation solver (ODETLAP) applied to the compression and restoration of terrain data used for Geographical Information Systems (GIS). ODET-LAP can be used to reconstruct a compressed elevation map, or to generate a dense regular grid from airborne Light Detection and Ranging (LIDAR) point cloud data. With previous methods, the time to execute ODETLAP does not scale well with the size of the input elevation map, resulting in running times that are prohibitively long for large data sets. Our algorithm divides the data set into patches, runs ODET-LAP on each patch, and then merges the patches together. This method gives two distinct speed improvements. First, we provide scalability by reducing the complexity such that the execution time grows almost linearly with the size of the input, even when run on a single processor. Second, we are able to calculate ODETLAP on the patches concurrently in a parallel or distributed environment. Our new patchbased implementation takes 2 seconds to run ODETLAP on an 800 Ă— 800 elevation map using 128 processors, while the original version of ODETLAP takes nearly 10 minutes on a single processor (271 times longer). We demonstrate the effectiveness of the new algorithm by running it on data sets as large as 16000 Ă— 16000 on a cluster of computers. We also discuss our preliminary results from running on an IBM Blue Gene/L system with 32,768 processors
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