323 research outputs found
ERTS-1 evaluation of natural resources management applications in the Great Basin
The relatively cloud free weather in the Great Basin has allowed the accumulation of several dates of excellent ERTS-1 imagery. Mountains, valleys, playas, stream courses, canyons, alluvial fans, and other landforms are readily delineated on ERTS-1 imagery, particularly with MSS-5. Each band is useful for identifying and studying one or more natural resource features. For example, crested wheatgrass seedings were most easily identified and measured on MSS-7. Color enhancements simulating CIR were useful for depicting meadow and phreatophytic vegetation along water bodies and stream courses. Work is underway to inventory and monitor wildfire areas by age and successional status. Inventories have been completed on crested wheatgrass seedings over the entire State of Nevada, and inventories of playa surfaces, water surfaces, phreatophytic vegetation, snow cover, meadows, and other features is continuing. Vegetation ecotones are being delineated for vegetation mapping. The pinyon/juniper-northern desert shrub ecotone has been identified with considerable success. Phenology changes can be used to describe vegetation changes for management
Validation of current body composition estimation equations for men over 60 years of age
This study compared five skinfold equations for body composition (Jackson & Pollock\u27s Sum of 7 {dollar}\{{dollar}JP7{dollar}\}{dollar} and Sum of 3 {dollar}\{{dollar}JP3{dollar}\}{dollar}; Jackson & Pollock\u27s Sum of 4 {dollar}\{{dollar}Y4{dollar}\}{dollar} and Sum of 3 {dollar}\{{dollar}Y3{dollar}\}{dollar} for the YMCA, and Durnin and Womersley\u27s Sum of 7 {dollar}\{{dollar}DW{dollar}\}){dollar} with percent fat obtained from underwater weighing. Subjects were ninety-seven adult males aged 60-80 years. Skinfold measurements were taken with Lange calipers and underwater weight (UWW) was determined in a seated position utilizing a load cell system with residual volume (RV) measured at the time of weighing; The skinfold equations achieved a mean correlation of.74 with underwater weighing. JP7 yielded the highest correlation (.78) and DW the lowest (.72). A 1RM-ANOVA indicated that all five equations produced significantly different results than UWW. The data showed that these equations are not as valid with the present study\u27s population as with those from which the equations were derived
The Impact of Guided Practice in Argument Analysis and Composition via Computer-Assisted Argument Mapping Software on Students’ Ability to Analyze and Compose Evidence-Based Arguments
The purpose of this quantitative action research study was to document the impact of the use of computer-assisted argument mapping (CAAM) upon high school students’ ability to analyze and compose evidence-based arguments. The study used a one-group pretest posttest design with a convenience sample of the participant researcher’s seventy-one high school sophomores. During the six-week study, each participant generated four sets of artifacts, each consisting of two argument analysis maps from provided source arguments and one argument composition map representing the participant’s position on the given topic. Artifacts were generated at four separate benchmarks, the pretest, week four, week five, and the posttest. Between the pretest and week four, students completed a self-paced computerized tutorial on critical thinking (CT) that emphasized argumentation skills, such as grouping ideas, the parts of an argument, locating arguments in a text, evaluating arguments for errors in logic and credibility, and creating argument maps. In weeks four and five of the study, students applied the skills learned in the tutorial to full-length argumentative articles provided by the participant researcher. Benchmarks for weeks four, five, and the posttest consisted of the same task as the pretest, two analysis maps reconstructing the authors’ arguments and one argument composition map representing the participant’s position on the given topic. Composite scores were analyzed to determine an overall effect, while each component score, analysis and composition, provided an indication of reading comprehension ability and argument construction ability, respectively. The use of CAAM as a means of fostering the CT skills necessary for the comprehension and composition of arguments (analysis, synthesis, and organization) proved beneficial, with the results of the study showing both significance (t=7.7077, crit. t=1.67, ∝= 05, 95% confidence level) and an appreciable effect size (d = .9147)
Natural resource inventories and management applications in the Great Basin
ERTS-1 resolution capabilities and repetitive coverage have allowed the acquisition of several statewide inventories of natural resource features not previously completed or that could not be completed in any other way. Familiarity with landform, tone, pattern and other converging factors, along with multidate imagery, has been required. Nevada's vegetation has been mapped from ERTS-1. Dynamic characteristics of the landscape have been studied. Sequential ERTS-1 imagery has proved its usefulness for mapping vegetation, following vegetation phenology changes, monitoring changes in lakes and reservoirs (including water quality), determining changes in surface mining use, making fire fuel estimates and determining potential hazard, mapping the distribution of rain and snow events, making range readiness determinations, monitoring marshland management practices and other uses. Feasibility has been determined, but details of incorporating the data in management systems awaits further research and development. The need is to accurately define the steps necessary to extract required or usable information from ERTS imagery and fit it into on-going management programs
Trophic structure of soil animal food webs of deciduous forests as analyzed by stable isotope labeling
Characterization of ultrafiltration membranes by tracer's retention:Comparison of methods sensitivity and reproducibility
Previous studies have shown that the absolute membrane cut-off and the value quoted by the manufacturers may be very different because of differences in methodologies and testing conditions. The origin of this discrepancy is often difficult to identify as the characterization method used by the membrane manufacturers is not specified. The goal of this study is to evaluate in terms of sensitivity, repeatability and reproducibility the methodologies used by a working group including membrane manufacturers, end-users and a research laboratory. The five selected membranes are hollow fibers used in drinking water production. They are made of various materials with different configurations (internal–external and external–internal type) and molecular weight cut-offs. Different types of tracers are used: dextrans, poly (ethylene glycol)s, poly(ethylene oxide)s, MS2 bacteriophage filtrated in single sized solution or in mixture. Results collected lead to a better understanding of the origin of discrepancies and allow to define the best operating conditions (tracer's type, working conditions range, data treatment methods,…) providing the most appropriate, accurate and reproducible testing protocol according to the selected application
Submerged membrane bioreactor for waste water treatment: determination of the shear stresses produced by coarse bubbles
Submerged membrane bioreactor for waste water treatment: determination of the shear stresses produced by coarse bubble
Rheological study of sludge of membranes bioreactors for water treatment: protocol, limitations and link with the filtration
The submerged membranes bio-reactors (sMBR) are more and more visible in the field of waste water treatment. The membrane fouling, that causes a drastic fall of the performances, can be limited by the application of a swarm of bubbles close to the membrane surfaces. This aeration as a major factor of the energetic expense of these processes, lets numerous studies to focus on the understanding of the mechanisms linking the bubbles swarm with fouling.. In this background, the rheological tools appeared to be useful to understand the behaviour of sludge under shear stress. In order to be sure to get significant results, we used three types of rheological measurements: i) the influence of shear rate on shear stress; ii) the influence of upward then downward stages of shear stress on viscosity; iii) the influence of the alternation of two stages of shear stress with implementation times identical to those of sMBR aeration. Besides a viscoplastic behaviour previously observed, a phenomenon of hysteresis appeared. The transparent upper plan used on the rheometer exhibited formations of aggregative structures “in roll”. Sludges of a sMBR using different sequencing of aeration are compared: the developed protocols enabled to differentiate those sludges, with characteristic results depending on mechanical applications. The aim of this work is, eventually, to propose some correlations between usual characteristics of the process and aeration operating parameters, in order to propose an aeration policy improving energetic performances
- …