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Sensitivity Assessment (sensitivity + assessment)
Selected AbstractsCLIMATE CHHANGE SENSITIVITY ASSESSMENT ON UPPER MISSISSIPPI RIVER BASIN STREAMFLOWS USING SWAT,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 4 2006Manoj Jha ABSTRACT: The Soil and Water Assessment Tool (SWAT) model was used to assess the effects of potential future climate change on the hydrology of the Upper Mississippi River Basin (UMRB). Calibration and validation of SWAT were performed using monthly stream flows for 1968,1987 and 1988,1997, respectively. The R2 and Nash-Sutcliffe simulation efficiency values computed for the monthly comparisons were 0.74 and 0.69 for the calibration period and 0.82 and 0.81 for the validation period. The effects of nine 30-year (1968 to 1997) sensitivity runs and six climate change scenarios were then analyzed, relative to a scenario baseline. A doubling of atmospheric CO2 to 660 ppmv (while holding other climate variables constant) resulted in a 36 percent increase in average annual streamflow while average annual flow changes of ,49, ,26, 28, and 58 percent were predicted for precipitation change scenarios of ,20, ,10, 10, and 20 percent, respectively. Mean annual streamflow changes of 51,10, 2, ,6, 38, and 27 percent were predicted by SWAT in response to climate change projections generated from the CISRO-RegCM2, CCC, CCSR, CISRO-Mk2, GFDL, and HadCMS general circulation model scenarios. High seasonal variability was also predicted within individual climate change scenarios and large variability was indicated between scenarios within specific months. Overall, the climate change scenarios reveal a large degree of uncertainty in current climate change forecasts for the region. The results also indicate that the simulated UMRB hydrology is very sensitive to current forecasted future climate changes. [source] Field simultaneous measurements, modeling, and simulation of harmonic components in a small generation-transmission networkEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 1 2007S. Ríos M Abstract This paper presents a detailed deterministic model for a small electrical transmission network (110,kV), representing a large (150,MVA) industrial Copper mine production plant. This model is developed and validated with simultaneous field measurements. The network topology allows two operating modes, ring and open ring operation, without disturbing the busbar loads. Experimental results of,simultaneous,measurements at the three load busbars confirm the simulation results obtained with a state space deterministic model. A sensitivity assessment of busbar harmonic distortions, based on singular and eigenvalues analysis, is also presented. Copyright © 2006 John Wiley & Sons, Ltd. [source] A method to assess the sensitivity of sedimentary communities to fishing activitiesAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 3 2009Harvey Tyler-Walters Abstract 1.Methods of sensitivity assessment to identify species and habitats in need of management or protection have been available since the 1970s. 2.The approach to sensitivity assessment adopted by the Marine Life Information Network (MarLIN) assumes that the sensitivity of a community or biotope is dependent on the species within it. However, the application of this approach to sedimentary communities, especially offshore, is complex because of a lack of knowledge of the structural or functional role of many sedimentary species. 3.This paper describes a method to assess the overall sensitivity of sedimentary communities, based on the intolerance and recoverability of component species to physical disturbance. A range of methods were applied to identify the best combinations of abundant, dominant or high biomass species for the assessment of sensitivity in the sedimentary communities examined. 4.Results showed that reporting the most frequent species' sensitivity assessment, irrespective of the four methods used to select species, consistently underestimated the total sensitivity of the community. In contrast, reporting the most sensitive assessment from those species selected resulted in a range of biotope sensitivities from very low to very high, that was better able to discriminate between the sensitivities of the communities examined. 5.The assumptions behind the methodology, its limitations and potential application are discussed. © Crown copyright 2008. Reproduced with permission of Her majesty's stationery office. Published by John Wiley & Sons, Ltd. [source] Sensitivity Analysis for Nonrandom Dropout: A Local Influence ApproachBIOMETRICS, Issue 1 2001Geert Verbeke Summary. Diggle and Kenward (1994, Applied Statistics43, 49,93) proposed a selection model for continuous longitudinal data subject to nonrandom dropout. It has provoked a large debate about the role for such models. The original enthusiasm was followed by skepticism about the strong but untestable assumptions on which this type of model invariably rests. Since then, the view has emerged that these models should ideally be made part of a sensitivity analysis. This paper presents a formal and flexible approach to such a sensitivity assessment based on local influence (Cook, 1986, Journal of the Royal Statistical Society, Series B48, 133,169). The influence of perturbing a missing-at-random dropout model in the direction of nonrandom dropout is explored. The method is applied to data from a randomized experiment on the inhibition of testosterone production in rats. [source] New paediatric contrast test: Hiding Heidi low-contrast ,face' testCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 5 2003Clinical Research ABSTRACT Background:,The Hiding Heidi low-contrast ,face' test is a new paediatric contrast test to evaluate the ability to detect objects with low contrast. The purpose of the present study was to compare the Hiding Heidi low-contrast ,face' test (HH) with the Pelli,Robson contrast sensitivity test (PR) and the functional acuity contrast test (FACT) in the low-contrast assessment. Methods:,Thirty university students participated in the present study. The contrast ability was evaluated by using three different methods: HH, PR and FACT. The HH was repeated on two separate occasions to test the repeatability. Results:,There was a significant positive correlation between HH and PR (r = 0.65, P < 0.01); between HH and FACT at 6 cycles per degree (c.p.d.; r = 0.64, P < 0.01); between HH and FACT at 3 c.p.d. (r = 0.91, P < 0.01); and between HH and FACT at 1.5 c.p.d. (r = 0.56, P < 0.01). The paired t -test showed a significant difference between HH and PR (t = ,6.05, P < 0.01); between HH and FACT at 6 c.p.d. (t = ,11.16, P < 0.01); between HH and FACT at 3 c.p.d. (t = ,8.35, P < 0.01); and between HH and FACT at 1.5 c.p.d. (t = ,5.64, P < 0.01). They had good agreement. The HH had a high repeatability. Conclusions:,The HH had a positive correlation but produced significantly different readings when compared with FACT and PR. The features and role of HH in clinical contrast sensitivity assessment are discussed. [source] Maternal sensitivity in interactions with three- and 12-month-old infants: Stability, structural composition, and developmental consequencesINFANT AND CHILD DEVELOPMENT, Issue 3 2004Arnold Lohaus This study addresses three topics related to the structural components of maternal sensitivity: (a) The stability of sensitivity over a nine-month period, (b) the predictability of maternal sensitivity assessed at 12 months from early parameters of parenting and (c) the relation between maternal sensitivity and developmental outcomes assessed at 12 months. Maternal sensitivity and its components (signal perception, correct interpretation, prompt, and appropriate reaction) were evaluated for 60 mother,infant-dyads when their infants were aged three and 12 months. Additional parameters of early parenting were maternal emotional warmth and behavioural contingency. Developmental outcome measures were the amount of infant crying and the quality of attachment at twelve months. The results showed close correlations between the sensitivity components suggesting a unidimensional structure for maternal sensitivity. The sensitivity assessments were significantly related to measures of maternal warmth. Stability of maternal sensitivity over time was, however, quite low. There was no relation between the early sensitivity assessments and later developmental outcomes, whereas there was a significant relation between the sensitivity parameters assessed at twelve months and developmental outcomes. The results indicate changes in the meaning of maternal sensitivity during infants' development. Copyright © 2004 John Wiley & Sons, Ltd. [source] | ||||||||||