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Improvement of the Soil Moisture Diagnostic Equation for Estimating Root-Zone Soil Moisture

Description: Soil moisture information can be used accurately in determining the timing and amount of irrigation applied to plants. Pan and Pan et al. proposed a robust and simple daily diagnostic equation for estimating daily soil moisture. The diagnostic equation evaluates the relationship between the soil moisture loss function and the summation weighted average of precipitation. The loss function uses the sinusoidal wave function which employs day of the year (DOY) to evaluate the seasonal variation in soil moisture loss for a given year. This was incorporated into the daily diagnostic equation to estimate the daily soil moisture for a location. Solar radiation is an energy source that drives the energy and water exchanges between vegetation and the atmosphere (i.e., evapotranspiration), and thus impacts the soil moisture dry-down. In this paper, two parameters (the actual solar radiation and the clear sky solar radiation) are introduced into loss function coefficient to improve the estimation of soil moisture. After the Introduction of the solar radiation data into soil moisture loss function, a slight improvement was observed in the estimated daily soil moisture. Pan observed that generally the correlation coefficient between the estimated and the observed soil moisture is above 0.75 and the root mean square error is below 5.0 (%v/v). The introduction solar radiation data (i.e. clear sky solar radiation and actual solar) improve the correlation coefficient average for all the sites evaluated by 0.03 when the root mean square error is generally below 4.5(%v/v) for the entire root zone.
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Date: May 2018
Creator: Omotere, Olumide Olubunmi
Partner: UNT Libraries

Final Report for Formulation of Moist Dynamicsa nd Physics for Future Climate Models

Description: In this project, one of our goals is to develop atmospheric models, in which innovative ideas on improving the quality of moisture predictions can be tested. Our other goal is to develop an explicit time integration scheme based on the multi-point differencing (MED) that does the same job as an implicit trapezoidal scheme but uses information only from limited number of grid points. Below we discuss the work performed at Colorado State University toward these goals during the funding period indicated above.
Date: June 1, 2006
Creator: Konor, Celal S.
Partner: UNT Libraries Government Documents Department

Forecasting Trafficability of Soils, Report Number 3, The Development of Methods for Predicting Soil Moisture Content: Volume 2, Prediction Sites at Vicksburg Mississippi

Description: Preface: The study was initiated in early 1951 to develop methods of predicting the moisture content of several soils in the vicinity of Vicksburg, Mississippi.
Date: October 1954
Creator: Waterways Experiment Station (U.S.)
Partner: UNT Libraries Government Documents Department

MODEL 9975 SHIPPING PACKAGE: IMPACT OF CAPLUG REMOVAL ON FIBERBOARD MOISTURE LEVEL

Description: Two 9975 shipping packages were removed from KAC and provided to SRNL for test purposes, after both packages were found to exceed the 1 inch maximum criterion for the axial gap at the top of the package. Package 9975-01818 was found with an axial gap of 1.437 inch, and an estimated 2.5 liters of excess moisture in the lower fiberboard layers. Package 9975-02287 was found with an axial gap of 1.008 inch, and only slightly elevated moisture levels relative to typical packages. Prior data from the 9975 Surveillance Program has shown that the 9975 drum provides a degree of isolation, and will tend to preserve fiberboard moisture levels for an extended period of time. Both packages were provided to SRNL to identify whether removal of the 4 caplugs in each package would allow moisture to escape the package. Following testing with the caplugs removed for approximately 1 year, this report documents the findings from this effort. Two 9975 shipping packages removed from service in K-Area Complex (KAC) due to an excessive axial gap have been tested in SRNL to determine if caplug removal would facilitate the reduction of excess fiberboard moisture. An additional question to be answered through this testing was whether the resulting moisture loss would reduce the axial gap, reversing the effect seen during storage with excess moisture present. These packages have completed approximately 1 year in test, during which time the weight of each package has steadily decreased as a result of moisture migration out of the package. However, elevated moisture levels still remain in the packages. During this test period, the bottom fiberboard layers of package 9975-01818 (which contained the greater amount of excess moisture) experienced further compaction, and the axial gap of both packages has increased. This effort has shown that removal of the caplugs ...
Date: June 23, 2011
Creator: Daugherty, W.
Partner: UNT Libraries Government Documents Department

Formulation of Moist Dynamics and Physics for Future Climate Models

Description: In this project, one of our goals is to develop atmospheric models, in which innovative ideas on improving the quality of moisture predictions can be tested. Our other goal is to develop an explicit time integration scheme based on the multi-point differencing that does the same job as an implicit trapezoidal scheme but uses information only from limited number of grid points.
Date: April 30, 2008
Creator: Arakwa, Celal S. Konor and Akio
Partner: UNT Libraries Government Documents Department

Measurement of Tritium in Gas Phase Soil Moisture and Helium-3 in Soil Gas at the Hanford Townsite and 100 K Area

Description: In 1999, eight soil gas sampling points ranging in depth from 4.9 ft to 32 ft below ground surface (bgs) in two clusters were installed adjacent to well 699-41-1, south of the Hanford Townsite. Fifteen soil gas sampling points, ranging in depth from 7.0 ft to 10.4 ft bgs, were installed to the north and east of the 100-K East Reactor facility. Gas phase soil moisture samples were collected using silica gel traps from all eight sampling locations adjacent to well 699-41-1 and eight locations at the 100-K Area. Soil gas samples for helium-3 measurements were collected at all sampling points. No detectable tritium (<240 pCi/L) was found in the soil moisture samples from either the Hanford Townsite or 100-K Area sampling points. This behavior suggests that tritiated moisture from groundwater is not migrating upward to the sampling points and there are no large vadose zone sources of tritium at either location. Helium-3 analyses of the soil gas samples showed significant enrichments relative to ambient air helium-3 concentrations with a depth dependence consistent with a groundwater source from decay of tritium. Helium-3/helium-4 ratios (normalized to the abundances in ambient air) at the Hanford Townsite ranged from 1.012 at 5 feet below ground surface (bgs) to 2.157 at 32 feet bgs. Helium-3/helium-4 ratios at the 100-K area ranged from 0.972 to 1.131. Based on results from the 100-K area, we believe that a major tritium plume does not lie within that study area. The data also suggest there may be a tritium groundwater plume or a source of helium-3 to the southeast of the study area. We recommend that the study be continued by the placement of additional soil gas sampling points along the perimeter road to the west and to the south of the initial study area.
Date: July 5, 2000
Creator: Olsen, Khris B.; Patton, Gregory W.; Poreda, R.; Dresel, P Evan & Evans, John C.
Partner: UNT Libraries Government Documents Department

Use of Borehole Geophysical Methods in Determining in Situ Bulk Densities and Water Contents in Unconsolidated Materials: Final Report

Description: Introduction: The purpose of this study was to assess the capabilities of the WES geophysical downhole logging equipment for obtaining in situ bulk densities and water contents in unconsolidated materials, to establish a log analysis procedure applicable from one site to another, and to compare geophysically derived properties with those obtained from laboratory analysis of samples.
Date: September 1977
Creator: Hunt, Richard W.
Partner: UNT Libraries Government Documents Department

The Use of Radar Methods to Determine Moisture Content in the Vadose Zone

Description: The objective of our three-year research project is to determine the optimal way to use radar methods to obtain information about moisture content in the vadose zone. In our research we will focus on two specific aspects of the link between radar images and moisture content. The first aspect or question we address is: Can we use a measure of the dielectric constant of a volume of the subsurface to determine the moisture content of that volume? The second question we address is involved specifically with the issue of spatial heterogeneity. Rather than using radar data to get estimates of moisture content at specific locations, can we use the radar data to directly obtain information about the way in which the level of moisture content varies spatially?
Date: June 1, 2000
Creator: Knight, Rosemary
Partner: UNT Libraries Government Documents Department

The Use of Radar Methods to Determine Moisture Content in the Vadose Zone

Description: Moisture content is a critical parameter affecting both liquid-phase and vapor-phase contaminant transport in the vadose zone. The objective of our three-year research project is to determine the optimal way to use radar methods as a non-invasive means of determining in situ moisture content.
Date: June 1, 2003
Creator: Knight, Rosemary
Partner: UNT Libraries Government Documents Department

Irrigation in Humid Climates

Description: Report discussing and promoting irrigation practices in the eastern United States, which, although its climate is humid, does not have sufficient soil moisture in drier seasons to produce a maximum crop yield.
Date: 1896
Creator: King, F. H. (Franklin Hiram), 1848-1911
Partner: UNT Libraries Government Documents Department

The Use of Radar Methods to Determine Moisture Content in the Vadose Zone

Description: Moisture content is a critical parameter affecting both liquid-phase and vapor-phase contaminant transport in the vadose zone. The objective of our three-year research project is to determine the optimal way to use radar methods as a non-invasive means of determining in situ moisture content.
Date: June 1, 2002
Creator: Knight, Rosemary
Partner: UNT Libraries Government Documents Department

The Use of Radar Methods to Determine Moisture Content in the Vadose Zone

Description: Moisture content is a critical parameter affecting both liquid-phase and vapor-phase contaminant transport in the vadose zone. The objective of our three-year research project is to determine the optimal way to use of radar methods--both surface and borehole--as a noninvasive means of determining in situ moisture content. In our research we focus on two specific aspects of the link between radar images and moisture content. The first question we address is: Can we use a measure of the dielectric constant of a volume of the subsurface to determine the moisture content of that volume? The second question we address is: Can we use the radar data to characterize the spatial variability in moisture content?
Date: June 1, 2001
Creator: Knight, Rosemary
Partner: UNT Libraries Government Documents Department

Moisture Metrics Project

Description: the goal of this project was to determine the optimum moisture levels for biomass processing for pellets commercially, by correlating data taken from numerous points in the process, and across several different feedstock materials produced and harvested using a variety of different management practices. This was to be done by correlating energy consumption and material through put rates with the moisture content of incoming biomass ( corn & wheat stubble, native grasses, weeds, & grass straws), and the quality of the final pellet product.This project disseminated the data through a public website, and answering questions form universities across Missouri that are engaged in biomass conversion technologies. Student interns from a local university were employed to help collect data, which enabled them to learn firsthand about biomass processing.
Date: August 31, 2011
Creator: Schuchmann, Mark
Partner: UNT Libraries Government Documents Department

INL Subsurface Wireless Sensor Platform

Description: The Idaho National Laboratory is developing a versatile micro-power sensor interface platform for periodic subsurface sensing of environmental variables important to waste disposal sites such as volumetric moisture, water potential, and temperature. The key characteristics of the platform architecture are that the platform is passive until externally energized --no internal power source is required -- and that it communicates with a "reader" via short-range telemetry - no wires penetrate the subsurface. Other significant attributes include the potential for a long service life and a compact size that makes it well suited for retrofitting existing landfill structures. Functionally, the sensor package is "read" by a short-range induction coil that activates and powers the sensor platform as well as detects the sensor output via a radio frequency signal generated by the onboard programmable interface controller microchip. As a result, the platform has a functional subsurface communication range of approximately 10 to 12 ft. and can only accept sensors that require low power to operate.
Date: October 1, 2005
Creator: Kunerth, Dennis C.; Svoboda, John M. & Johnson, James T.
Partner: UNT Libraries Government Documents Department

Monitoring Moisture Content in Surface Barriers Using a Passive Sensor Platform

Description: Work is being performed to develop a versatile micro-power sensor platform for the purpose of periodic, remote sensing of environmental variables such as subsurface moisture or radiation. The key characteristics of the platform architecture are that the components are passive, thereby requiring no internal power source and that it communicates with a &#34;reader&#34; via short range telemetry, i.e. no wires need penetrate barrier structure. Other significant attributes include the potential for a long service life and a compact size that makes it well suited for retrofitting existing barrier structures. Functionally, the sensor package is read by a short range induction coil that both activates/powers the sensor platform and detects the sensor output via a radio frequency signal generated by the onboard programmable interface controller microchip. To date, a prototype of the platform has been constructed and tested with a commercial moisture sensor. Work is now in progress to extend the capabilities of the existing platform to permit moisture sensing through landfill surface barriers (caps). Specifically, work is being performed to extend the telemetry range for transmission through a cap, select/develop low power sensor elements, and package the components to survive subsurface conditions. Considerations are being given to minimize package dimensions to permit retrofit applications.
Date: September 1, 2001
Creator: Kunerth, Dennis Clyde; Svoboda, John Mark & Lee, James Edwin
Partner: UNT Libraries Government Documents Department

Moisture-Strength Characteristics of Selected Soils in Thailand, Volume 1: Analysis and Application of Data

Description: Partial summary: "Soil moisture, soil strength, and other relevant data were collected in Thailand during two wet seasons and one dry season for use in the development of methods to predict soil trafficability for off-road ground contact vehicles in Southeast Asia. Data were collected at 75 test sites distributed in eight geographic areas which had differences in soils, weather regimes, terrain, and land use" (p. xi).
Date: August 1967
Creator: Kennedy, James Garland; Collins, J. G. & Smith, M. H.
Partner: UNT Libraries Government Documents Department

Moisture performance of sealed attics in the mixed-humid climate

Description: Oak Ridge National Laboratory studied 8 homes in the mixed-humid climate, 4 with vented attics and 4 with sealed attics. ORNL wanted to understand the moisture performance of the sealed attic and how it affected the interior environment. We found that the attic and interior of sealed attic homes were more humid than the attic and interior observed in vented attic homes. This is due to the lack of ventilation in the sealed attic. Historically attics have been vented to dehumidify the attic and interior of the home. A sealed attic design greatly reduces the venting potential and thus this drying pathway and can cause elevated interior moisture over a vented attic home. Despite the elevated attic and interior moisture in the sealed attic homes, so far no mold or material degradation has been found. The roof sheathing moisture content has stayed below 20%, indicating low potential for material degradation. Also the relative humidity at the roof sheathing has stayed within the ASHRAE 160 design criteria except for a short time during the 2011/2012 winter. This was due to a combination of the sealed attic design (minimal venting to the outside) and the duct work not being operated in the attic which usually provides a dehumidification pathway. It was also found that when the humidity was controlled using the HVAC system, it resulted in 7% more cooling energy consumption. In the mixed-humid climate this reduces the cost effectiveness of the sealed attic design as a solution for bringing ducts into a semi-conditioned space. Because of this we are recommending the other alternatives be used to bringing ducts into the conditioned space in both new construction and retrofit work in the mixed-humid climate.
Date: December 1, 2013
Creator: Boudreaux, Philip R; Pallin, Simon B & Jackson, Roderick K
Partner: UNT Libraries Government Documents Department