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Full-Text Articles in Bioresource and Agricultural Engineering

Report Of The Poplar Working Group, Steve Strauss Jan 1999

Report Of The Poplar Working Group, Steve Strauss

United States Department of Energy: Publications

Poplars consist of all species of the genus Populus, including cottonwoods, aspens, and the many interspecies hybrids in common use (Dickmann and Stuart 1983). Our working group focused on the fungal pathogens, arthropod herbivores, and weed competitors of Populus in the United States. However, bacterial and viral diseases of Populus are significant in Europe, and genetic engineering approaches toward their control or management are being studied. The key aspects of poplar biology important to understanding the use of pest resistance genes are described below.


2h Solid-State Nmr Investigation Of Terephthalate Dynamics And Orientation In Mixed-Anion Hydrotalcite-Like Compounds, Robert S. Maxwell, Ravi K. Kukkadapu, James E. Amonette, Herman Cho Jan 1999

2h Solid-State Nmr Investigation Of Terephthalate Dynamics And Orientation In Mixed-Anion Hydrotalcite-Like Compounds, Robert S. Maxwell, Ravi K. Kukkadapu, James E. Amonette, Herman Cho

United States Department of Energy: Publications

The dynamics and orientations of interlayer terephthalate (TA) anions in mixed-anion hydrotalcite-like compounds [Mg1-x Alx(OH)2](AyB1-y)x/2•nH2O, where A = p-C6D4(COO)22- and B ) CO32-] were investigated by 2H variable-temperature solid-state nuclear magnetic resonance (NMR) spectroscopy. Two dominant 003 d spacings, 7.6 and 14.2 Å, were observed by X-ray diffraction (XRD) in these samples, suggesting that there were at least two interlayer environments. Over the range of layer charges studied (0.37 ≥ x ≥ 0.29), the intensity …


Metal Oxide Surfaces And Their Interactions With Aqueous Solutions And Microbial Organisms, Gordon E. Brown Jr., Victor Henrich, William Casey, David Clark, Carrick Eggleston, Andrew Felmy Andrew Felmy, D. Wayne Goodman, Michael Gratzel, Gary Maciel, Maureen I. Mccarthy, Kenneth H. Nealson, Dimitri Sverjensky, Michael Toney, John M. Zachara Jan 1999

Metal Oxide Surfaces And Their Interactions With Aqueous Solutions And Microbial Organisms, Gordon E. Brown Jr., Victor Henrich, William Casey, David Clark, Carrick Eggleston, Andrew Felmy Andrew Felmy, D. Wayne Goodman, Michael Gratzel, Gary Maciel, Maureen I. Mccarthy, Kenneth H. Nealson, Dimitri Sverjensky, Michael Toney, John M. Zachara

United States Department of Energy: Publications

During the past decade, interest in chemical reactions occurring at metal oxide-aqueous solution interfaces has increased significantly because of their importance in a variety of fields, including atmospheric chemistry, heterogeneous catalysis and photocatalysis, chemical sensing, corrosion science, environmental chemistry and geochemistry, metallurgy and ore beneficiation, metal oxide crystal growth, soil science, semiconductor manufacturing and cleaning, and tribology. The metal oxide-aqueous solution interface is reactive due to acid-base, ligand-exchange, and/or redox chemistry involving protons (hydronium ions), hydroxyl groups, aqueous metal ions, and aqueous organic species and also complexes among these species. Interfacial localization of those species (adsorption) may result from electrostatic, …


Climate Change Impacts On The Potential Productivity Of Corn And Winter Wheat In Their Primary United States Growing Regions, Robert Brown, Norman Rosenberg Jan 1999

Climate Change Impacts On The Potential Productivity Of Corn And Winter Wheat In Their Primary United States Growing Regions, Robert Brown, Norman Rosenberg

United States Department of Energy: Publications

We calculate the impacts of climate effects inferred from three atmospheric general circulation models (GCMs) at three levels of climate change severity associated with change in global mean temperature (GMT) of 1.0, 2.5 and 5.0 _C and three levels of atmospheric CO2 concentration ([CO2]) – 365 (no CO2 fertilization effect), 560 and 750 ppm – on the potential production of dryland winter wheat (Triticum aestivum L.) and corn (Zea mays L.) for the primary (current) U.S. growing regions of each crop. This analysis is a subset of the Global Change Assessment Model (GCAM) which has …


Below-Ground Respiratory Responses Of Sugar Maple And Red Maple Saplings To Atmospheric Co2 Enrichment And Elevated Air Temperature, Nelson Edwards, Richard Norby Jan 1999

Below-Ground Respiratory Responses Of Sugar Maple And Red Maple Saplings To Atmospheric Co2 Enrichment And Elevated Air Temperature, Nelson Edwards, Richard Norby

United States Department of Energy: Publications

The research described in this paper represents a part of a much broader research project with the general objective of describing the effects of elevated [CO2] and temperature on tree growth, physiological processes, and ecosystem-level processes. The specific objective of this research was to examine the below-ground respiratory responses of sugar maple (Acer saccharum Marsh.) and red maple (Acer rubrum L.) seedlings to elevated atmospheric [CO2] and temperature. Red maple and sugar maple seedlings were planted in the ground in each of 12 open-top chambers and exposed from 1994 through 1997 to ambient air …


Loss Detection In The Dairy Industry., Michael Quealy Jan 1999

Loss Detection In The Dairy Industry., Michael Quealy

Theses

In any waste management program, the primary objective must be minimizing product loss without having an affect on product quality. Good waste management is recognized as good manufacturing practice and optimizes the processes to gain the highest possible yield from the available raw materials. A good waste management program must involve the daily monitoring of effluent from the plant for volume and strength. This data needs to be analyzed sufficiently to obtain clear pictures of what problems are present and where they are originating. If this is achieved then the task of reducing the product loss is made much easier. …


A Case Study Of Bioengineering In America: Profits, Risks And Standards Of Value In The Commercialization Of Monsanto Company's Newleaf Potato, Bridget Lyons, Teresa Ralabate, Nadhim Frangul Jan 1999

A Case Study Of Bioengineering In America: Profits, Risks And Standards Of Value In The Commercialization Of Monsanto Company's Newleaf Potato, Bridget Lyons, Teresa Ralabate, Nadhim Frangul

WCBT Faculty Publications

Last year, approximately 45 million acres of American farmland were planted with crops that had been genetically engineered to either produce their own pesticides, or withstand herbicides. The long and short-term effects of this biotechnology on humans and the environment, are being studied, but remain unknown. Leading the way in the field of bioengineered crops is the Missouri-based Monsanto Company. Monsanto believes that current agricultural practices are inconsistent with sustainable development. The NewLeaf potato is one of three products Monsanto has created to feed the growing world population. The genetically engineered crop produces, in every cell of the plant, a …


Problems Of Irrigation In Developing Countries, Phillip Z. Kirpich, Dorota Z. Haman, Stuart W. Styles Jan 1999

Problems Of Irrigation In Developing Countries, Phillip Z. Kirpich, Dorota Z. Haman, Stuart W. Styles

BioResource and Agricultural Engineering

This paper describes the crucial importance of irrigated agriculture to developing countries and to the world as a whole. This is followed by a summary of key problems that restrict and diminish the benefits of irrigated agriculture. Solution of these problems will above all require a holistic approach and will require changes in the institutions involved. These institutions include those of the developing countries, of the developed countries that provide aid, and of the international financing and technical-assistance agencies. Engineers in the developed countries have had, and will continue to have, a leading role but will need some redirection. ASCE …


Fertigation Basics, Charles M. Burt Nov 1998

Fertigation Basics, Charles M. Burt

BioResource and Agricultural Engineering

Fertigation is widely practiced with drip irrigation, yet remains very unsophisticated. Major areas which need improvement are (i) making certain the irrigation system applies water with a high DU (uniformity), (ii) using proper injection pumps and protection hardware, (iii) recognizing that chemicals can interact with each other and with water to form precipitates which will clog emitters, (iv) understanding of nutrient ratios in plants and soil, (v) recognizing that nitrogen fertilization requires attention to the type of nitrogen, and (vi) developing programs for spoon-feeding chemicals. This paper covers the first 4 topics, plus discusses some specific fertilizers.


Comparison Of Water And Temperature Distribution Profiles Under Sand Tube Irrigation, Masoud Meshkat, Richard C. Warner, Stephen R. Workman Nov 1998

Comparison Of Water And Temperature Distribution Profiles Under Sand Tube Irrigation, Masoud Meshkat, Richard C. Warner, Stephen R. Workman

Biosystems and Agricultural Engineering Faculty Publications

Drip irrigation is one of the most efficient systems in delivering water to the plant root zone. Research has shown that the saturated, or nearly saturated, surface beneath the emitter may increase evaporation thereby reducing the irrigation efficiency. To increase the efficiency of surface applied drip irrigation on permanent tree crops a sand tube irrigation (STI) method was developed and tested. The sand tube method consists of removing a soil core beneath the emitter and filling the void with coarse sand. A weighing lysimeter was designed and instrumented to directly measure temporal evaporation during irrigation and for a period of …


Chemicals For Fertigation, Charles M. Burt Nov 1998

Chemicals For Fertigation, Charles M. Burt

BioResource and Agricultural Engineering

No abstract provided.


Modern Water Control And Management Practices In Irrigation: Impact On Performance, Charles M. Burt, Stuart W. Styles Oct 1998

Modern Water Control And Management Practices In Irrigation: Impact On Performance, Charles M. Burt, Stuart W. Styles

BioResource and Agricultural Engineering

This research addressed the basic questions of what levels of water delivery service are presently provided by irrigation projects having some aspect of modernization; what hardware and software features impact those levels of service; whether modern water control and management practices in irrigation make a positive difference in performance; and what universal lessons can be learned and applied.


Geotextile Feeding/Traffic Surfaces And Costs, Larry W. Turner Oct 1998

Geotextile Feeding/Traffic Surfaces And Costs, Larry W. Turner

Agricultural Engineering Extension Updates

Mud robs Kentucky beef and dairy producers of performance from their cattle herds in winter and spring conditions. To help avoid the problems associated with mud and reduced performance, concrete pads or lower-cost all-weather surfaces should be used wherever animals congregate--- feeding areas, animal traffic areas and loafing areas. Although concrete is probably the most desirable surface for durability and low maintenance, an all-weather surface can be constructed of geotextile fabric, rock and fine surface cover for less than 1/3 of the cost of concrete. Rock over bare soil in Kentucky requires approximately 12" of depth for stability. In contrast, …


Optimization Of Solid-State Fermentation Parameters For The Production Of Xylanase By Trichoderma Longibrachiatum On Wheat Bran, Elizabeth R. Ridder, Sue E. Nokes, Barbara L. Knutson Sep 1998

Optimization Of Solid-State Fermentation Parameters For The Production Of Xylanase By Trichoderma Longibrachiatum On Wheat Bran, Elizabeth R. Ridder, Sue E. Nokes, Barbara L. Knutson

Biosystems and Agricultural Engineering Faculty Publications

Solid-state fermentation has the potential to produce inexpensive enzymes for use in high-volume industrial applications. Process parameters such as substrate moisture content and length of fermentation can have a significant effect on the amount and timing of enzyme production. This study was conducted in two stages, a screening stage and an optimization stage, to determine the effects of moisture content of the substrate, surfactant addition upon inoculation, depth of the substrate, and duration of fermentation on xylanase activity produced by Trichoderma longibrachiatum. Screening fermentations were conducted at 25°C, 50 and 75% wet basis moisture content (w.b.), 0.0 and 0.2% …


Vegetated Filter Strip Removal Of Cattle Manure Constituents In Runoff, Teng T. Lim, Dwayne R. Edwards, Stephen R. Workman, Brian T. Larson, Lloyd Dunn Sep 1998

Vegetated Filter Strip Removal Of Cattle Manure Constituents In Runoff, Teng T. Lim, Dwayne R. Edwards, Stephen R. Workman, Brian T. Larson, Lloyd Dunn

Biosystems and Agricultural Engineering Faculty Publications

Pasture runoff can contribute to elevated concentrations of nutrients, solids, and bacteria in downstream waters. The objective of this study was to determine the effects of vegetative filter strip (VFS) length on concentrations and transport of nitrogen, phosphorus, solids and fecal coliform in runoff from plots treated with cattle manure. Three plots with dimensions of 2.4 × 30.5 m were used. The upper 12.2 m of each plot was treated with cattle manure, while the lower 18.3 m acted as a VFS. Runoff produced by rainfall simulators was sampled at VFS lengths of 0, 6.1, 12.2, and 18.3 m and …


Response Of Runoff Diazinon Concentration To Formulation And Post-Application Irrigation, Joshua R. Evans, Dwayne R. Edwards, Stephen R. Workman, R. Michael Williams Sep 1998

Response Of Runoff Diazinon Concentration To Formulation And Post-Application Irrigation, Joshua R. Evans, Dwayne R. Edwards, Stephen R. Workman, R. Michael Williams

Biosystems and Agricultural Engineering Faculty Publications

Pesticides used in urban environments can be transported in runoff to downstream waters and cause adverse environmental consequences. This experiment assessed the effects of post-application irrigation depth (0, 6.4, and 12.7 mm) and formulation (liquid and granular) on concentration and transport of diazinon (a pesticide commonly used for lawn insect control) in runoff from “tall” fescue (Festuca arundinacea Schreb.) plots. The post-application irrigation was applied using rainfall simulators immediately following diazinon application. The rainfall simulators were again used approximately 2 h after diazinon application to apply the equivalent of a heavy rainfall (64 mm/h for approximately 1.5 h) to generate …


Selection Of Irrigation Methods For Agriculture: Drip/Micro Irrigation, Charles M. Burt Aug 1998

Selection Of Irrigation Methods For Agriculture: Drip/Micro Irrigation, Charles M. Burt

BioResource and Agricultural Engineering

The ASCE On-Farm Committee has recently completed a draft of a manual (Bliesner et al, 1998) on "Selection of Irrigation Methods for Agriculture." One of the chapters describes drip/micro irrigation methods. Numerous variations of drip/micro designs are discussed, along with advantages and disadvantages. This paper provides an overview of some aspects of that chapter.


Drip/Micro Irrigation Survey For Delano-Earlimart Irrigation District, Charles M. Burt Jul 1998

Drip/Micro Irrigation Survey For Delano-Earlimart Irrigation District, Charles M. Burt

BioResource and Agricultural Engineering

Delano-Earlimart ID (DEID) has kept informal statistics on the use of drip and micro-irrigation (drip/micro) within its boundaries for several years. These statistics showed that there has been only a slight increase in the acreage of these systems over the past 10 years. Because the rate and extent of conversion to drip/micro may influence the type of future water delivery service needed from DEID, DEID management is interested in knowing more about farmer perceptions regarding these newer irrigation methods.

DEID obtained a grant from USBR Mid-Pacific region to examine perceptions of its farmers regarding future conversions to drip and micro-irrigation. …


Comparison Of Observed And Simulated Grow-Finish Swine Performance Under Summer Conditions, Larry W. Turner, Thomas C. Bridges, Richard D. Coffey, Richard S. Gates, Gary R. Parker, Tami M. Brown-Brandl, Douglas G. Overhults Jul 1998

Comparison Of Observed And Simulated Grow-Finish Swine Performance Under Summer Conditions, Larry W. Turner, Thomas C. Bridges, Richard D. Coffey, Richard S. Gates, Gary R. Parker, Tami M. Brown-Brandl, Douglas G. Overhults

Biosystems and Agricultural Engineering Faculty Publications

As a part of a National Pork Producers Council educational program, our research and extension team at the University of Kentucky was linked with an independent commercial swine producer to test the NCPIG model against observed commercial on-farm data. This experience provided improved information for model development as well as increased producer insight into the data input needs and potential benefits of modeling. Detailed production information comparisons between the NCPIG model and producer data are presented for summer time conditions to assess the validity of the NCPIG model for simulation of grow-finish swine performance. Results demonstrated that the NCPIG model …


Quality Of Runoff From Plots Treated With Municipal Sludge And Horse Bedding, Elizabeth L. Busheé, Dwayne R. Edwards, Philip A. Moore Jr. Jul 1998

Quality Of Runoff From Plots Treated With Municipal Sludge And Horse Bedding, Elizabeth L. Busheé, Dwayne R. Edwards, Philip A. Moore Jr.

Biosystems and Agricultural Engineering Faculty Publications

Land application of horse stall bedding and municipal sludge can increase runoff concentrations of nutrients, organic matter, and bacteria as well as steroidal hormones such as estrogen. Concentrations of materials in runoff from sites treated with animal manure can be reduced by aluminum sulfate, or alum [Al2(SO4)3•14H2O] treatment. The objectives of this study were to assess plots treated with horse stall bedding or municipal sludge for: (a) runoff quality [concentrations of nitrate nitrogen (NO3-N), ammonia nitrogen (NH3-N), orthophosphate-phosphorus (PO4-P), fecal coliform (FC), chemical oxygen demand (COD) …


Improving Water Properties To Increase Infiltration Characteristics, Richard W. O. Soppe, Stuart W. Styles Jun 1998

Improving Water Properties To Increase Infiltration Characteristics, Richard W. O. Soppe, Stuart W. Styles

BioResource and Agricultural Engineering

Water properties, such as the viscosity and surface tension, can be affected by temperature and surfactants to Increase infiltration rates into soils. Specifically, they will change the hydraulic conductivity of the soil. A simple soap solution and the new material PAM (inexpensive polymer chemical) were evaluated as surfactants. Laboratory experiments and field tests on a site in Davis, California were done to quantify the effects of changing the water properties. Additional effects, like the improved soil structure during infiltration and less soil particles in tailwater (reduced erosion due to runoff) were observed and are described in this paper. The conclusions …


On Farm Irrigation - The Shift From Art To Science, Charles M. Burt May 1998

On Farm Irrigation - The Shift From Art To Science, Charles M. Burt

BioResource and Agricultural Engineering

Excellent on-farm irrigation management and design have traditionally been promoted for reasons of improved yields and farm input costs. More recently, external pressures require even more detail to on-farm irrigation. These external pressures include competition for water by urban and environmental interests, plus degradation of aquifers and rivers. As irrigation progresses from an art to a science, new concepts must be adopted. Key points made in the paper relate to flexible water deliveries to farms, improved fertigation practices, the importance of on-farm irrigation evaluations, the use of an Irrigation Consumer Bill of Rights by dealers and farmers, and irrigation system …


Diffuse Reflectance Changes During The Culture Of Cottage Cheese, Frederick Alan Payne, R. Carol Freels, Sue E. Nokes, Richard S. Gates May 1998

Diffuse Reflectance Changes During The Culture Of Cottage Cheese, Frederick Alan Payne, R. Carol Freels, Sue E. Nokes, Richard S. Gates

Biosystems and Agricultural Engineering Faculty Publications

A sensor for measuring diffuse reflectance of milk during the typical 6-h culture of cottage cheese was installed in a local manufacturing facility. Diffuse reflectance was found to increase slowly during the first three hours of the culture and increase rapidly toward the end of fermentation. The correlation between parameters generated from the diffuse reflectance profile and cutting time was sufficient to develop an algorithm for cutting time prediction. An algorithm incorporating tmax (time from adding culture to the maximum rate of change in reflectance) and slope of the reflectance curve at tmax predicted the operator selected cutting …


Manipulation Of High Spatial Resolution Aircraft Remote Sensing Data For Use In Site-Specific Farming, Gabriel B. Senay, Andrew D. Ward, John G. Lyon, Norman R. Fausey, Sue E. Nokes Mar 1998

Manipulation Of High Spatial Resolution Aircraft Remote Sensing Data For Use In Site-Specific Farming, Gabriel B. Senay, Andrew D. Ward, John G. Lyon, Norman R. Fausey, Sue E. Nokes

Biosystems and Agricultural Engineering Faculty Publications

Three spatial data sets consisting of high spatial resolution (1 m) remote sensing images acquired in 12 spectral bands, an on-the-go yield map, and a Digital Elevation Model were co-registered and evaluated for spatial variability studies in a Geographic Information Systems environment. Separate on-the-go yield maps were developed for 3, 5, and 12 statistically significant mean yield classes. For each yield class, the corresponding mean spectral and elevation data were extracted. The relationship between mean spectral and yield data was strongly linear (r = 0.99). Also, a strong linear relationship between mean yield and elevation data (r = 0.92) was …


Water Level Sensor And Datalogger Testing And Demonstration, A. Burt, Mike Lehmkuhl, Charles M. Burt, Stuart W. Styles Feb 1998

Water Level Sensor And Datalogger Testing And Demonstration, A. Burt, Mike Lehmkuhl, Charles M. Burt, Stuart W. Styles

BioResource and Agricultural Engineering

Electronic water level sensing equipment is becoming increasingly important for the implementation of water conservation programs in irrigation districts. A need has risen for information on costs, advantages/disadvantages, required support equipment, and required maintenance for the various options. ITRC conducted a yearlong study on water level sensors and dataloggers and produced this report.


Influence Of Canal Geometry And Dynamics On Controllability, Theodor S. Strelkoff, Jean Luc Deltour, Charles M. Burt, Albert J. Clemmens, Jean Pierre Baume Jan 1998

Influence Of Canal Geometry And Dynamics On Controllability, Theodor S. Strelkoff, Jean Luc Deltour, Charles M. Burt, Albert J. Clemmens, Jean Pierre Baume

BioResource and Agricultural Engineering

This paper presents the results of the Task Committee on Canal Automation Algorithms with regard to the influence of canal properties on the controllability of irrigation canals. While the control provided by individual algorithms was not evaluated, studies were performed to illustrate inherent hydraulic limitations—the inability of canal pools to recover rapidly from disturbances or flow perturbations. Studies were performed in nondimensional form to develop a better understanding of how pool properties influence pool response. Three such studies were performed. First, nondimensional backwater curves were developed for a range of canal conditions. The second study involved the propagation of waves …


Binder Containing Plant Protein And Densified Refuse Fuel Cubes Made Using Same And Methods Of Making Them, Jerry D. Eastin, David Jones, Darin Dux, Harold Earl Egger Jan 1998

Binder Containing Plant Protein And Densified Refuse Fuel Cubes Made Using Same And Methods Of Making Them, Jerry D. Eastin, David Jones, Darin Dux, Harold Earl Egger

Department of Agricultural and Biological Systems Engineering: Faculty Publications

To form a binder from naturally occurring products or a fuel brick or pellet using the binder without extraction or purification steps, the binder utilizes proteins from the germ or endosperm of cereal grasses or from the seed of buckwheat, oil seed plants, Amaranthus or leguminous plants or from leaves or from grain stillage. The protein has a thermoplastic microstructure with linear polymers of molecular weight of at least 2,000 linked with peptide linkages of at least 50 in number. The binder is mixed with waste such as municipal waste without further processing and processed in a pelleting machine.


Biogenic Iron Mineralization Accompanying The Dissimilatory Reduction Of Hydrous Ferric Oxide By A Groundwater Bacterium, James K. Fredrickson, John M. Zachara, David Kennedy, Hailang Dong, Tullis Onstott, Nancy Hinman, Shu-Mei Li Jan 1998

Biogenic Iron Mineralization Accompanying The Dissimilatory Reduction Of Hydrous Ferric Oxide By A Groundwater Bacterium, James K. Fredrickson, John M. Zachara, David Kennedy, Hailang Dong, Tullis Onstott, Nancy Hinman, Shu-Mei Li

United States Department of Energy: Publications

Dissimilatory iron-reducing bacteria (DIRB) couple the oxidation of organic matter or H2 to the reduction of iron oxides. The factors controlling the rate and extent of these reduction reactions and the resulting solid phases are complex and poorly understood. Batch experiments were conducted with amorphous hydrous ferric oxide (HFO) and the DIRB Shewanella putrefaciens, strain CN32, in well-defined aqueous solutions to investigate the reduction of HFO and formation of biogenic Fe(II) minerals. Lactate-HFO solutions buffered with either bicarbonate or 1,4-piperazinediethanesulfonic acid (PIPES) containing various combinations of phosphate and anthraquinone-2,6-disulfonate (AQDS), were inoculated with S. putrefaciens CN32. AQDS, a humic …


The Effects Of Catalyst, Free Fatty Acids, And Water On Transecterification Of Beef Tallow, Fangrui Ma, L. D. Clements, Milford Hanna Jan 1998

The Effects Of Catalyst, Free Fatty Acids, And Water On Transecterification Of Beef Tallow, Fangrui Ma, L. D. Clements, Milford Hanna

Industrial Agricultural Products Center: Publications and Information

Transesterification of beef tallow and methanol is affected by many factors. Catalyst, free fatty acids, and water in beef tallow, and reaction time were investigated. Sodium hydroxide (NUOH) was a more effective catalyst than sodium methoxide (NaMeOj. NaOH and NaMeO reached their maximum activities at 0.3% and 0.5%, w/w of beef tallow, respectively. The presence of water had more negative effect on transesterification than did the presence of free fatty acids (FFA). For best results, the water content of beef tallow should be kept not beyond 0.0696, w/w. FFA content of beef tallow should be kept below 0.596, w/w. The …


Effect Of Parameter Distributions On Uncertainty Analysis Of Hydrologic Models, C. Thomas Haan, Daniel E. Storm, T. Al-Issa, Sandeep Prabhu, George J. Sabbagh, Dwayne R. Edwards Jan 1998

Effect Of Parameter Distributions On Uncertainty Analysis Of Hydrologic Models, C. Thomas Haan, Daniel E. Storm, T. Al-Issa, Sandeep Prabhu, George J. Sabbagh, Dwayne R. Edwards

Biosystems and Agricultural Engineering Faculty Publications

Increasing concern about the accuracy of hydrologic and water quality models has prompted interest in procedures for evaluating the uncertainty associated with these models. If a Monte Carlo simulation is used in an uncertainty analysis, assumptions must be made relative to the probability distributions to assign to the model input parameters. Some have indicated that since these parameters can not be readily determined, uncertainty analysis is of limited value. In this article we have evaluated the impact of parameter distribution assumptions on estimates of model output uncertainty. We conclude that good estimates of the means and variances of the input …