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Articles 2491 - 2520 of 3083
Full-Text Articles in Bioresource and Agricultural Engineering
Development Of A Finite-Element Stored Grain Ecosystem Model, Michael D. Montross, Dirk E. Maier, Kamyar Haghighi
Development Of A Finite-Element Stored Grain Ecosystem Model, Michael D. Montross, Dirk E. Maier, Kamyar Haghighi
Biosystems and Agricultural Engineering Faculty Publications
An axisymmetric finite–element model was developed that predicts the heat, mass, and momentum transfer that occurred in upright corrugated steel storage structures due to conduction, diffusion, and natural convection using realistic boundary conditions. Weather data that included hourly total solar radiation, wind speed, ambient temperature, and relative humidity were used to model the temperature, moisture content, dry matter loss, and maize weevil development during storage with no aeration, and with ambient and chilled aeration. Periods of aeration were simulated assuming a uniform airflow rate through the grain mass. Heat and mass balances were used to calculate the temperature and absolute …
Validation Of A Finite-Element Stored Grain Ecosystem Model, Michael D. Montross, Dirk E. Maier, Kamyar Haghighi
Validation Of A Finite-Element Stored Grain Ecosystem Model, Michael D. Montross, Dirk E. Maier, Kamyar Haghighi
Biosystems and Agricultural Engineering Faculty Publications
An axisymmetric finite–element model was validated with respect to predicting the heat, mass, and momentum transfer that occurred in upright corrugated–steel storage bins due to conduction, diffusion, and natural convection using realistic boundary conditions. Hourly weather data that included hourly total solar radiation, wind speed, ambient temperature, and relative humidity were used to model the corn temperature and moisture content during storage with no aeration, and with ambient and chilled aeration. Periods of aeration were simulated assuming a uniform airflow rate through the grain mass. Sixteen bins with a capacity of 11.7 t each and instrumented with temperature cables were …
Water Delivery Service As A Determinant Of Irrigation Project Performance, Stuart W. Styles, M. A. Marino
Water Delivery Service As A Determinant Of Irrigation Project Performance, Stuart W. Styles, M. A. Marino
BioResource and Agricultural Engineering
Performance of an irrigation system is represented by its measured levels of achievement in terms of one or several parameters that are chosen as indicators of the system’s goals. The purpose of this paper is to utilize and refine a set of evaluation indicators that can be used to describe the irrigation performance for sixteen international irrigation projects in less-developed countries. The irrigation performance of many international irrigation projects in less-developed countries has been reported as poor. The cause of the poor irrigation performance has been blamed on technical, financial, managerial, social, and/or institutional causes. This study is specifically designed …
Electric Load Shifting In Irrigation Districts - California's Program, Charles M. Burt, Ricardo Amón, Darren Cordova
Electric Load Shifting In Irrigation Districts - California's Program, Charles M. Burt, Ricardo Amón, Darren Cordova
BioResource and Agricultural Engineering
During the 2000-2001 winter, California experienced a severe imbalance in electricity supply and demand that resulted in blackouts and brownouts. The state legislature initiated a number of emergency programs, one of which (Senate Bill 5x) was targeted for irrigation districts. The primary goal of SB 5x is to reduce peak period electricity demand. The California Energy Commission (CEC), acting under authority of Section 5(b) of the legislation, developed the "Agricultural Peak Load Reduction Program". The program was announced on June 1, 2001, and Cal Poly ITRC administers the irrigation district portion of the program for CEC. During the first 9 …
Advances In Plc-Based Canal Automation, Charles M. Burt, Xianshu Piao
Advances In Plc-Based Canal Automation, Charles M. Burt, Xianshu Piao
BioResource and Agricultural Engineering
A short history of canal automation is given. PLC-based canal automation is relatively new. Advances in PLC-based canal automation are listed. Also listed are some of the remaining challenges. Recent advances have been made in understanding unsteady flow simulation procedures, the form of the control algorithms used, the tuning procedures for these control algorithms, and the field programming of the algorithms into PLCs. The experiences of the Cal Poly Irrigation Training and Research Center (ITRC) in automating a variety of canals with upstream and downstream control are given.
Case Study: Installation Of Canal Control Structures On The Government Highline Canal, Ram Dhan Khalsa, Stuart W. Styles, Charles M. Burt, Bob Norman
Case Study: Installation Of Canal Control Structures On The Government Highline Canal, Ram Dhan Khalsa, Stuart W. Styles, Charles M. Burt, Bob Norman
BioResource and Agricultural Engineering
The Government Highline Canal Modernization Study was completed in April 2000 to evaluate options for reducing the flow rate requirement of the Government Highline Canal in order to increase the water supply in the “15-Mile Reach” of the Colorado River, thereby helping sustain habitat for fish species identified as endangered. The intent was to develop a design for which Colorado River diversions could be better matched to on-farm demands. It was determined that canal modernization, in the form of automated canal structures, in-system storage, and new operational procedures could significantly reduce operational spill. A systematic evaluation of the existing canal …
Modernizing Irrigational Facilities At Sutter Mutual Water Company: A Case Study, Frederick F. Schantz, Stuart W. Styles, Beau J. Freeman, Charles M. Burt, Doughlas Stevens
Modernizing Irrigational Facilities At Sutter Mutual Water Company: A Case Study, Frederick F. Schantz, Stuart W. Styles, Beau J. Freeman, Charles M. Burt, Doughlas Stevens
BioResource and Agricultural Engineering
In 1999 Sutter Mutual Water Company (SMWC) began an effort to modernize its water-distribution system in an attempt to reduce operation and maintenance costs and conserve water and power resources. The primary technical support was provided by professionals from the Irrigation Training and Research Center (ITRC), California Polytechnic State University (Cal Poly), San Luis Obispo. Additional technical expertise was provided by Concepts in Controls of Visalia, California and Wilson Pumps of Woodland, California. This modernization project was partially funded by the United States Bureau of Reclamation (USBR), Mid-Pacific Region, Northern Area Office, though a Field Services Program Grant and technical …
Glenn-Colusa Irrigation District Flow Monitoring Program, Dennis Perkins, Stuart W. Styles, Marcus Y. Yasutake
Glenn-Colusa Irrigation District Flow Monitoring Program, Dennis Perkins, Stuart W. Styles, Marcus Y. Yasutake
BioResource and Agricultural Engineering
In 1996, the United States Bureau of Reclamation (USBR), Mid-Pacific Region, Northern California Area Office began the Willows Flow Monitoring Program. The program objective was to monitor, in near real-time, 85% of the Sacramento River Diversions from Shasta Dam to Sacramento. Several site visits were conducted to the District and their diversion points along the Sacramento River by USBR and Irrigation Training and Research Center (ITRC) staff from California Polytechnic state University (Cal Poly), San Luis Obispo. One of the sites identified for flow monitoring was the Glen-Colusa Irrigation District (GCID) canal at the Stoney Creek Siphon. At question was …
Breaking The Technology Barriers Imposed By Cast-In Place Concrete Pipe In Irrigation Districts: Case Study Of South San Joaquin Irrigation District, Charles M. Burt, Michael B. Gilton, Kevin Johnson, Keith Crowe
Breaking The Technology Barriers Imposed By Cast-In Place Concrete Pipe In Irrigation Districts: Case Study Of South San Joaquin Irrigation District, Charles M. Burt, Michael B. Gilton, Kevin Johnson, Keith Crowe
BioResource and Agricultural Engineering
South San Joaquin Irrigation District (SSJID) in Manteca, California, is beginning an ambitious modernization program to increase its water delivery flexibility. The district has over 200 miles of 30-60 inch cast-in-place (CIP) concrete pipeline that currently allow for little flexibility. SSJID will install four reinforced concrete interceptor pipelines and regulating reservoirs to redistribute water among the CIP pipelines and provide improved flexibility. The district's goal is to improve efficiency and encourage farmers with pressurized irrigation systems to shift from well water to surface water.
Closure To "Flap Gate Design For Automatic Upstream Canal Water Level Control", Charles M. Burt, Russdon Angold, Mike Lehmkuhl, Stuart Styles
Closure To "Flap Gate Design For Automatic Upstream Canal Water Level Control", Charles M. Burt, Russdon Angold, Mike Lehmkuhl, Stuart Styles
BioResource and Agricultural Engineering
No abstract provided.
Comparison Of Repair Costs Of Two Wheel Drive Tractors Under Tanzania Conditions, S. M. Mpanduji
Comparison Of Repair Costs Of Two Wheel Drive Tractors Under Tanzania Conditions, S. M. Mpanduji
Tanzania Journal of Engineering and Technology (TJET)
The repair costs of 2WD tractors were investigated in order to provide important information, which lacks in the scope of agricultural mechanization in Tanzania. Previously repair cost functions established for tractors in developed countries were used for both theoretical and practical purposes. The findings of this study have revealed that repair costs of tractors vary substantially from one make to another. The prediction functions developed in this study indicated that the magnitudes of repair costs in Tanzania are higher than the repair costs established in Europe and North America. The reason for this could be either due to high cost …
Investigation Of Forces Acting On Plain Discs, S. M. Mpanduji
Investigation Of Forces Acting On Plain Discs, S. M. Mpanduji
Tanzania Journal of Engineering and Technology (TJET)
An investigation was carried out to study the mutually perpendicular forces generated by rotating and non-rotating plain discs similar to those used in disc ploughs. Experiments were conducted in a soil bin containing sand loam soil (Ryton sand) where forces were measured while changing disc rake and sweep angles. The results showed that draught forces were higher for non-rotating discs, while vertical and lateral forces were lower compared to rotating discs. Rotating discs were found to be suitable for counteracting high side forces because of less draught and higher lateral forces. The recommended optimum angles are between 8°–12° for disc …
Cattle Handling Facilities: Planning, Components, And Layouts, José R. Bicudo, Samuel G. Mcneill, Larry W. Turner, Roy Burris, John Anderson
Cattle Handling Facilities: Planning, Components, And Layouts, José R. Bicudo, Samuel G. Mcneill, Larry W. Turner, Roy Burris, John Anderson
Agricultural Engineering Extension Publications
Cattle handling facilities are used to confine cattle safely and efficiently for close observation and to perform routine health and management procedures. Adequate facilities are an essential part of an efficient cattle operation for any producer who wants to improve marketing, cattle health, and production. A well-planned handling facility can help you save money by making easier practices such as preventive health management, pregnancy testing, implanting, controlling parasites, vaccinating, castrating, and dehorning.
A Reduced–Cost Mechanized System For Handling And Curing Mechanically–Harvested Burley Tobacco, Greg A. Camenisch, Larry G. Wells, Timothy D. Smith, George A. Duncan
A Reduced–Cost Mechanized System For Handling And Curing Mechanically–Harvested Burley Tobacco, Greg A. Camenisch, Larry G. Wells, Timothy D. Smith, George A. Duncan
Biosystems and Agricultural Engineering Faculty Publications
An experimental system was tested in which mechanically harvested burley tobacco plants placed onto steel slotted receivers were retrieved from a field, transported to a field curing structure, and placed onto the structure for air curing by a single worker. The system consisted of a tractor–towed, trailer mechanism that engaged and hoisted loads of approximately 360 burley plants of approximately 1 Mg mass. Ten slotted steel rails, 3.05 m long, holding 36 notched plants were placed onto parallel wooden beams suspended at a height of 2.13 m by wooden posts set in the ground. Burley tobacco was cured in this …
A Portable Rainfall Simulator For Plot–Scale Runoff Studies, J. Byron Humphry, Tommy C. Daniel, Dwayne R. Edwards, Andrew N. Sharpley
A Portable Rainfall Simulator For Plot–Scale Runoff Studies, J. Byron Humphry, Tommy C. Daniel, Dwayne R. Edwards, Andrew N. Sharpley
Biosystems and Agricultural Engineering Faculty Publications
Rainfall simulators have a long history of successful use in both laboratory and field investigations. Many plot–scale simulators, however, have been difficult to operate and transport in the field, especially in remote locations where water or electricity is unavailable. This article describes a new rainfall simulator that is relatively easy to operate and transport to and from the field while maintaining critical intensity, distribution, and energy characteristics of natural rainfall. The simulator frame is constructed from lightweight aluminum pipe with a single 50 WSQ nozzle centered at a height of 3 m (9.8 ft). An operating nozzle pressure of 28 …
Friction Of Wheat: Grain-On-Grain And On Corrugated Steel, Marek Molenda, Jozef Horabik, I. Joe Ross, Michael D. Montross
Friction Of Wheat: Grain-On-Grain And On Corrugated Steel, Marek Molenda, Jozef Horabik, I. Joe Ross, Michael D. Montross
Biosystems and Agricultural Engineering Faculty Publications
Coefficients of friction of wheat for grain–on–grain and on galvanized corrugated steel sheet were investigated using a modified direct shear apparatus. Tests were conducted under a normal pressure of 20.7 kPa using soft red winter wheat at a moisture content of 11.2% (w.b.) and an uncompressed bulk density of 740 kg/m3. Three consolidation procedures and three methods of deposition of grain in the test chamber were used. Test results of grain–on–grain friction showed that consolidation procedure markedly influenced the force–displacement relationship, while its influence on the coefficients of friction were small. Shearing to peak strength as a consolidation …
Review Of: Eat Your Genes: How Genetically Modified Food Is Entering Our Diet (Stephen Nottingham Ed.), Natalie Duval
Review Of: Eat Your Genes: How Genetically Modified Food Is Entering Our Diet (Stephen Nottingham Ed.), Natalie Duval
RISK: Health, Safety & Environment (1990-2002)
Review of the book: "Eat Your Genes: How Genetically Modified Food Is Entering Our Diet," by Stephen Nottingham, (St. Martin's Press 1999). Introduction, Glossary, Bibliography, Index. ISBN 1-85649-578-7 [212 pp. $17.95. Softbound, St. Martin's Press, Inc., New York, NY 10010].
Characterization Of Vadose Zone Sediment: Uncontaminated Rcra Borehole Core Samples And Composite Samples, R. J. Serne, B. N. Bjornstad, H. T. Schaef, B. A. Williams, D. C. Lanigan, D. G. Horton, R. E. Clayton, A. V. Mitroshkov, V. L. Legore, M. J. O’Hara, C. F. Brown, K. E. Parker, I. V. Kutnyakov, J. N. Serne, G. V. Last, Steven Smith, C. W. Lindenmeier, John M. Zachara, D. B. Burke
Characterization Of Vadose Zone Sediment: Uncontaminated Rcra Borehole Core Samples And Composite Samples, R. J. Serne, B. N. Bjornstad, H. T. Schaef, B. A. Williams, D. C. Lanigan, D. G. Horton, R. E. Clayton, A. V. Mitroshkov, V. L. Legore, M. J. O’Hara, C. F. Brown, K. E. Parker, I. V. Kutnyakov, J. N. Serne, G. V. Last, Steven Smith, C. W. Lindenmeier, John M. Zachara, D. B. Burke
United States Department of Energy: Publications
The overall goal of the of the Tank Farm Vadose Zone Project, led by CH2M HILL Hanford Group, Inc., is to define risks from past and future single-shell tank farm activities. To meet this goal, CH2M HILL Hanford Group, Inc. asked scientists from Pacific Northwest National Laboratory to perform detailed analyses on vadose zone sediment from within the S-SX Waste Management Area. This report is one in a series of four reports to present the results of these analyses. Specifically, this report contains all the geologic, geochemical, and selected physical characterization data collected on vadose zone sediment recovered from Resource …
Evaporation From Irrigated Agricultural Land In California, Charles M. Burt, Andrew Mutziger, Daniel Howes, Kenneth H. Solomon
Evaporation From Irrigated Agricultural Land In California, Charles M. Burt, Andrew Mutziger, Daniel Howes, Kenneth H. Solomon
BioResource and Agricultural Engineering
No abstract provided.
Variable Frequency Drives And Scada — Are They Worthwhile Investments?, Charles M. Burt, Daniel J. Howes
Variable Frequency Drives And Scada — Are They Worthwhile Investments?, Charles M. Burt, Daniel J. Howes
BioResource and Agricultural Engineering
Managers and personnel from five California irrigation districs were interviewed to determine if installing variable frequency drives (VFDs) and supervisory control and data acquisition (SCADA) systems were worthwhile investments.
Infrared Inspection, Charles M. Burt, Daniel J. Howes
Infrared Inspection, Charles M. Burt, Daniel J. Howes
BioResource and Agricultural Engineering
Infrared thermography is the use of infrared radiation to qualitatively and quantitatively express heat signatures and heat differences. Infrared inspection can help identify weak connections in an electrical box, uneven heating of pump windings, overheating of bearings, and many other possibly devastating problems well before any failure occurs. The use of thermography as a preventative tool can increase system reliability and efficiency.
Modeling The Inhibition Of The Bacterial Reduction Of U(Vi) By Β-Mno2(S), Chongxuan Liu, John M. Zachara, James K. Fredrickson, David W. Kennedy, Alice Dohnalkova
Modeling The Inhibition Of The Bacterial Reduction Of U(Vi) By Β-Mno2(S), Chongxuan Liu, John M. Zachara, James K. Fredrickson, David W. Kennedy, Alice Dohnalkova
United States Department of Energy: Publications
Pyrolusite (β-MnO2(s)) was used to assess the influence of a competitive electron acceptor on the kinetics of reduction of aqueous uranyl carbonate by a dissimilatory metal-reducing bacterium (DMRB), Shewanella putrefaciens strain CN32. The enzymatic reduction of U(VI) and β-MnO2(s) and the abiotic redox reaction between β-MnO2(s) and biogenic uraninite (UO2(s)) were independently investigated to allow for interpretation of studies of U(VI) bioreduction in the presence of β-MnO2(s). Uranyl bioreduction to UO2(s) by CN32 with H2 as the electron donor followed Monod kinetics, with a maximum specific reduction rate of 110 µM/h/10 …
Basic Design Of Replogle Flumes, Charles M. Burt, Stuart W. Styles
Basic Design Of Replogle Flumes, Charles M. Burt, Stuart W. Styles
BioResource and Agricultural Engineering
To facilitate accurate flow measurement, this paper describes specific design and construction considerations applicable to Replogle flumes in irrigation applications. A design example is provided to illustrate these concepts.
Side Mounted Doppler Flow Meter For Canals, Stuart W. Styles
Side Mounted Doppler Flow Meter For Canals, Stuart W. Styles
BioResource and Agricultural Engineering
The Irrigation Training and Research Center has undertaken a performance review of advanced electronic flow measurement technologies in irrigation applications. An example is the SonTek Argonaut Side-Looking (SL) Doppler Flow Meter.
Doppler Flow Meters For Turnouts, Stuart W. Styles
Doppler Flow Meters For Turnouts, Stuart W. Styles
BioResource and Agricultural Engineering
Irrigation districts, farmers and other agricultural and environmental water users need reliable and low-cost flow meters with integrated dataloggers to measure water velocity and depth with a high level of precision. The Irrigation Training and Research Center has undertaken a performance review of advanced electronic flow measurement technologies in irrigation applications. Examples are the Unidata STARFLOW and the MACE AgriFlo Ultrasonic Doppler Meters.
Variable Frequency Drives - Planning Your System, Charles M. Burt
Variable Frequency Drives - Planning Your System, Charles M. Burt
BioResource and Agricultural Engineering
Many irrigation districts are installing Variable Frequency Drives (VFDs) to increase their level of service to their customers and/or to reduce their energy consumption. This brochure is intended to help irrigation districts properly evaluate what type of VFD they need and how to install it.
However, not all VFDs are the same. The performance quality of a VFD will depend on the characteristics of the particular VFD, as well as how the VFD system is set up. Many times it is the seemingly small details that will have a large impact on performance in the long run. This brochure is …
Biomineralization Of Poorly Crystalline Fe(Iii) Oxides By Dissimilatory Metal Reducing Bacteria (Dmrb), John M. Zachara, Ravi K. Kukkadapu, James K. Fredrickson, Yuri A. Gorby, Steven C. Smith
Biomineralization Of Poorly Crystalline Fe(Iii) Oxides By Dissimilatory Metal Reducing Bacteria (Dmrb), John M. Zachara, Ravi K. Kukkadapu, James K. Fredrickson, Yuri A. Gorby, Steven C. Smith
United States Department of Energy: Publications
Dissimilatory metal reducing bacteria (DMRB) catalyze the reduction of Fe(III) to Fe(II) in anoxic soils, sediments, and groundwater. Two-line ferrihydrite is a bioavailable Fe(III) oxide form that is exploited by DMRB as a terminal electron acceptor. A wide variety of biomineralization products result from the interaction of DMRB with 2-line ferrihydrite. Here we describe the state of knowledge on the biotransformation of synthetic 2-line ferrihydrite by laboratory cultures of DMRB using select published data and new experimental results. A facultative DMRB is emphasized (Shewanella putrefaciens) upon which most of this work has been performed. Key factors controlling the identity of …
Reduction Kinetics Of Fe(Iii), Co(Iii), U(Vi), Cr(Vi), And Tc(Vii) In Cultures Of Dissimilatory Metal-Reducing Bacteria, Chongxuan Liu, Yuri A. Gorby, John M. Zachara, James K. Fredrickson, Christopher F. Brown
Reduction Kinetics Of Fe(Iii), Co(Iii), U(Vi), Cr(Vi), And Tc(Vii) In Cultures Of Dissimilatory Metal-Reducing Bacteria, Chongxuan Liu, Yuri A. Gorby, John M. Zachara, James K. Fredrickson, Christopher F. Brown
United States Department of Energy: Publications
The reduction kinetics of Fe(III)citrate, Fe(III)NTA, Co(III)EDTA−, U(VI)O22+, Cr(VI)O42−, and Tc(VII)O4− were studied in cultures of dissimilatory metal reducing bacteria (DMRB): Shewanella alga strain BrY, Shewanella putrefaciens strain CN32, Shewanella oneidensis strain MR-1, and Geobacter metallireducens strain GS-15. Reduction rates were metal specific with the following rate trend: Fe (III)citrate ≥ Fe(III)NTA > Co(III)EDTA− ›› UO2 2+ > CrO42− > TcO4−, except for CrO42− when H2 was used as electron donor. The metal reduction rates were also electron donor dependent with faster rates …
Influence Of Mn Oxides On The Reduction Of Uranium(Vi) By The Metal-Reducing Bacterium Shewanella Putrefaciens, James K. Fredrickson, John M. Zachara, David Kennedy, Chongxuan Liu, Martine Duff, Douglas Hunter, Alice Dohnalkova
Influence Of Mn Oxides On The Reduction Of Uranium(Vi) By The Metal-Reducing Bacterium Shewanella Putrefaciens, James K. Fredrickson, John M. Zachara, David Kennedy, Chongxuan Liu, Martine Duff, Douglas Hunter, Alice Dohnalkova
United States Department of Energy: Publications
The potential for Mn oxides to modify the biogeochemical behavior of U during reduction by the subsurface bacterium Shewanella putrefaciens strain CN32 was investigated using synthetic Mn(III/IV) oxides (pyrolusite [β-MnO2], bixbyite [Mn2O3] and K+-birnessite [K4Mn14O27 • 8H2O]). In the absence of bacteria, pyrolusite and bixbyite oxidized biogenic uraninite (UO2[s]) to soluble U(VI) species, with bixbyite being the most rapid oxidant. The Mn(III/IV) oxides lowered the bioreduction rate of U(VI) relative to rates in their absence or in the presence of gibbsite …
Sorption Of Cs+ To Micaceous Subsurface Sediments From The Hanford Site, Usa, John M. Zachara, Steven Smith, Chongxuan Liu, James Mckinley, R. Jeffrey Serne, Paul Gassman
Sorption Of Cs+ To Micaceous Subsurface Sediments From The Hanford Site, Usa, John M. Zachara, Steven Smith, Chongxuan Liu, James Mckinley, R. Jeffrey Serne, Paul Gassman
United States Department of Energy: Publications
The sorption of Cs+ was investigated over a large concentration range (10-9–10-2 mol/L) on subsurface sediments from a United States nuclear materials site (Hanford) where high-level nuclear wastes (HLW) have been accidentally released to the vadose zone. The sediment sorbs large amounts of radiocesium, but expedited migration has been observed when HLW (a NaNO3 brine) is the carrier. Cs+ sorption was measured on homoionic sediments (Na+, K+, Ca2+) with electrolyte concentrations ranging from 0.01 to 1.0 mol/L. In Na+ electrolyte, concentrations were extended to near saturation with …