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Minor Adjustments (minor + adjustment)
Selected AbstractsUsing SWAT to Model Streamflow in Two River Basins With Ground and Satellite Precipitation Data,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 1 2009Kenneth J. Tobin Abstract:, Both ground rain gauge and remotely sensed precipitation (Next Generation Weather Radar , NEXRAD Stage III) data have been used to support spatially distributed hydrological modeling. This study is unique in that it utilizes and compares the performance of National Weather Service (NWS) rain gauge, NEXRAD Stage III, and Tropical Rainfall Measurement Mission (TRMM) 3B42 (Version 6) data for the hydrological modeling of the Middle Nueces River Watershed in South Texas and Middle Rio Grande Watershed in South Texas and northern Mexico. The hydrologic model chosen for this study is the Soil and Water Assessment Tool (SWAT), which is a comprehensive, physical-based tool that models watershed hydrology and water quality within stream reaches. Minor adjustments to selected model parameters were applied to make parameter values more realistic based on results from previous studies. In both watersheds, NEXRAD Stage III data yields results with low mass balance error between simulated and actual streamflow (±13%) and high monthly Nash-Sutcliffe efficiency coefficients (NS > 0.60) for both calibration (July 1, 2003 to December 31, 2006) and validation (2007) periods. In the Middle Rio Grande Watershed NEXRAD Stage III data also yield robust daily results (time averaged over a three-day period) with NS values of (0.60-0.88). TRMM 3B42 data generate simulations for the Middle Rio Grande Watershed of variable qualtiy (MBE = +13 to ,16%; NS = 0.38-0.94; RMSE = 0.07-0.65), but greatly overestimates streamflow during the calibration period in the Middle Nueces Watershed. During the calibration period use of NWS rain gauge data does not generate acceptable simulations in both watersheds. Significantly, our study is the first to successfully demonstrate the utility of satellite-estimated precipitation (TRMM 3B42) in supporting hydrologic modeling with SWAT; thereby, potentially extending the realm (between 50°N and 50°S) where remotely sensed precipitation data can support hydrologic modeling outside of regions that have modern, ground-based radar networks (i.e., much of the third world). [source] INVESTIGATION OF ELASTIC INVERSION ATTRIBUTES USING THE EXPANSIBLE CLAY MODEL FOR WATER SATURATIONJOURNAL OF PETROLEUM GEOLOGY, Issue 2 2009J. O. Ugbo Quantitative X-ray diffraction has been used to characterize water saturation levels in complex shaly sand reservoirs (i.e. shaly sands with infrequent carbonates and minor proportions of iron-rich minerals such as pyrite and siderite). The results led to the design of a total expansible clay model for water saturation, which is similar in form to the Dual Water model except that the excess effect of the clay minerals has been accounted for by a volume-conductivity relationship, rather than one of the usual volume-porosity translations, effectively reducing the uncertainties in estimating water saturation. Given the ambiguities associated with predicting these petrophysical properties from data on rock properties, such as mineralogy, an investigation of the relationship of estimated water saturation based on the total expansible clay model to independently determined rock properties was undertaken using well log inversion and forward modelling techniques. The results show that there is consistency in the relationship between water saturation estimates made from the total expansible clay model and known elastic parameters such as primary and shear-wave sonic velocity (Vp, Vs), bulk density (,b) and impedance (I), when the Raymer-Gardner-Hunt model is used. Use of the Raymer-Gardner-Hunt model to reconstruct the required rock-physics relationship avoids the classic limitation of the more advanced Gassman model, which assumes that the dry shear modulus is equivalent to the wet shear modulus (,dry=,wet). The present work raises further questions on the application of the Voigt-Reuss-Hill (VRH) limits, or the Hashin Shtrikman bounds for averaging the effective shear modulus of the dry matrix in complex shaly sand reservoirs, where a two-mineral matrix is normally assumed. The study shows the inapplicability of the VRH or Hashin-Shtrikman averaging techniques but provides a minor adjustment to the averaging that solves the problems faced in reconstructing the relationships between directly measured elastic properties and derived petrophysical properties for this type of reservoir rock. [source] Understanding anorexia nervosa through analysis of thematic content of letters in an adolescent sampleEUROPEAN EATING DISORDERS REVIEW, Issue 5 2006Glen Freedman Abstract Objective Positive and negative themes about their illness have been identified in an adult population with anorexia nervosa. It was our goal to explore the thematic content of the letters written by an adolescent population in order to better our understanding of how this different population relates to the illness. Method Twenty-seven adolescents with anorexia nervosa were asked to write two letters to their eating disorder, one addressing it as a friend and the other, as an enemy. The coding scheme initially developed by Serpell and Treasure, with minor adjustments, was used to code the letters by two trained raters, with high inter-rater reliability. Results Many similarities and a few notable differences between the adolescent population and an adult population were noted. Compared to an adult population, adolescents valued to a greater degree the sense of feeling looked after by the disorder and the increased attention that they felt the disorder provided. In contrast, they did not view loss of periods as a benefit. Regarding perceived costs of anorexia nervosa, adolescents described a greater degree of psychological distress in relation to the disorder, and a greater sense of having been tricked by the disorder. They did not describe as much frustration with preoccupation with thoughts about food or of being controlled by food. All other themes were not considered appreciably different in terms of percentage of statements or of subjects. Discussion An understanding of how adolescents relate to their illness in terms of themes can help to provide the therapist with a sense of where a patient is in terms of motivation and readiness for recovery. This in turn can aid in the determination of an appropriate treatment approach that is most likely to foster an optimal therapeutic alliance and to enhance motivation to recover. Copyright © 2006 John Wiley & Sons, Ltd and Eating Disorders Association. [source] Landscape and Coast Development of A Lowland Fjord Margin Following Deglaciation, East GreenlandGEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 3 2001Louise Hansen The landscapes of western Jameson Land bordering Hall Bredning fjord comprise upper river basins, glacial landscapes, lower river basins and a near-shore zone. The upper river basins are incised into bedrock and display no cover of young sediments whilst the glacial landscapes, located closer to the coast, are dominated by Pleistocene deposits and an irregular topography with hills and ridges. The lower river basins, dissecting the glacial landscapes, are connected to the upper river basins and contain well-defined Holocene delta terraces. The near-shore zone, which includes the present coast, displays a few raised shorelines. Geomorphological observations combined with stratigraphic work and 14C dates provide a chronological framework for the development of landscape and shoreline, as presented by a four-stage reconstruction. The first stage covers the deglaciation of western Jameson Land at the Weichselian-Holocene transition after a collapse of the main fjord glacier in Hall Bredning. The sea inundated the low-lying areas on Jameson Land forming small side-entry fjord basins that possibly follow the track of older valleys. This was followed by a second stage, the paraglacial period, when large meltwater production and sediment transport resulted in a fast infilling of the side-entry fjord basins by deltas. These are now exposed in terraces in the lower river basins at 70,80 m a.s.l. During a third stage, the relaxation period, fluvial activity decreased and the land surface was increasingly occupied by a cover of tundra vegetation. A glacio-isostatic rebound resulted in a relative sea level fall and fluvial incision. During stages two and three the coast was exposed to shallow marine processes that aided the alignment of the coast. Stages one to three presumably lasted for less than 2000 years. During stage four, the stable period, lasting for several thousand years till the present, there were minor adjustments of shoreline and landscape. The four-step reconstruction describes the sedimentary response of a lowland fjord margin to dramatic changes in climate and sea level. The distribution of erosion and sedimentation during this development was mainly controlled by topography. The reconstruction of the latest environmental development of Jameson Land puts new light on Jameson Land's long and complex Quaternary stratigraphic record. The reconstruction may also be used as a model for the interpretation of deposits in similar areas elsewhere. [source] The utility of the Dutch Arthritis Impact Measurement Scales 2 for assessing health status in individuals with haemophilia: a pilot studyHAEMOPHILIA, Issue 6 2000N. L. U. Van Meeteren The aim of this pilot study was to examine the usefulness of the Dutch version of the Arthritis Impact Measurement Scales 2 (D-AIMS2)in assessing the health status of Dutch individuals with haemophilia. Sixty-eight individuals with mild, moderate, and severe haemophilia attending our clinic for their annual check-up participated. They first completed the Canadian Occupational Performance Measure (COPM). The D-AIMS2 was filled in afterwards at home. With the COPM, individuals rated their specific problematic activities of daily life (ADL), as well as the severity and importance of each problem. The D-AIMS2 is a comprehensive, self-administered questionnaire that evaluates functional health status. Fifty-seven individuals completed and returned the D-AIMS2. Reliability analysis demonstrated good internal consistency for the scales (Cronbach's ,=0.76,1.00), as well as for the components (,=0.80,0.88), except for the component ,social interaction' (,=0.44). Criterion validity of the D-AIMS2 was assessed by comparison with COPM outcomes; 80% of the problematic ADLs were included in the questionnaire, 20% were missing. Correlations between the D-AIMS2 components ,physical health' and ,symptoms' with predicted scores of those individuals by a highly experienced physiotherapist (r=0.63 and 0.53, respectively) substantiated its concurrent validity. Based on these results we concluded that the D-AIMS2, with minor adjustments, can be an appropriate tool for assessing the health status of Dutch haemophilia patients. [source] Modeling, experimenting, and improving skid steering on a 6 × 6 all-terrain mobile platformJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 2 2010J.-C. Fauroux Multiple-wheel all-terrain vehicles without a steering system must use great amounts of power when skid steering. Skid steering is modeled with emphasis put on the ground contact forces of the wheels according to the mass distribution of the vehicle. To increase steering efficiency, it is possible to modify the distribution of the normal contact forces on the wheels. This paper focuses on two aspects: first, it provides a model and an experimental study of skid steering on an all-road 6 × 6 electric wheelchair, the Kokoon mobile platform. Second, it studies two configurations of the distribution of the normal forces on the six wheels, obtained via suspension adjustments. This was both modeled and experimented. Contact forces were measured with a six-component force plate. The first results show that skid steering can be substantially improved by only minor adjustments to the suspensions. This setting decreases the required longitudinal forces applied by the engines and improves the steering ability of the vehicle or robot. Skid-steering characteristic parameters, such as the position of the center of rotation and absorbed skid power, are also dealt with in this paper. © 2010 Wiley Periodicals, Inc. [source] A new fabrication technique utilizing a composite material applied to orthopedic bracingPOLYMER COMPOSITES, Issue 1 2002Bryan J. Morrison An orthopedic brace fabrication and fitting technique was explored as a rapid and cost-effective alternative process to polypropylene fabrication. Other potential benefits could also be reduced weight and lower profile with the added advantage of allowing profile and firmness variation where desired. The novel process concept is based on the finding that a partially cured composite remains somewhat malleable. Clinicians conceivably can adjust an ankle-foot brace to the patient directly before fully curing the brace. Flexure experiments assessed both the partial curing concept and the ability to post-form. Results indicate that partial curing followed by ambient or heated adjustments and full curing compromises the strength by no more than 7%. However, adjustments resulted in a net displacement change averaging only 50% of that desired when heat was applied. It is also possible to post-form the fully cured brace. This compromises the material strength significantly in the deformed area, but it may be feasible for minor adjustments where applied loads are not extreme. This research demonstrates the feasibility of the process as an alternative to current techniques, especially for patients needing a strong brace. [source] Microsatellite DNA analysis of success in conserving genetic diversity after 33 years of refuge management for the desert pupfish complexANIMAL CONSERVATION, Issue 4 2008H. Koike Abstract Refuge populations of Cyprinodon macularius and Cyprinodon eremus, the extant members of the endangered desert pupfish complex, have been maintained for up to 33 years in semi-natural refuges. We examined the success of the refuge program in maintaining diversity at four microsatellite DNA loci in 24 refuge populations of C. macularius and six of C. eremus that include, respectively, seven and four lineages representing original translocations from the wild. These lineages have been maintained with essentially no inoculations of genetic material from the wild and, except for one refuge, no intermixing of lineages. Comparison with wild-source populations showed marked declines in diversity within local refuges and within lineages, but relatively minor declines for the composite of all refuge populations for each species. In genetic makeup, the refuge populations generally clustered by lineage, indicating significant genetic drift early in lineage history. The results indicate that, with relatively minor adjustments in management, the refuge program can successfully preserve a large portion of the wild genetic diversity in the desert pupfish complex. [source] | ||||||||||