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Simulating Nitrogen Management Effects Of Subsurface Drainage Water Quality, A S. Azevedo, P. Singh, Ramesh S. Kanwar, Lajpat R. Ahuja Dec 1997

Simulating Nitrogen Management Effects Of Subsurface Drainage Water Quality, A S. Azevedo, P. Singh, Ramesh S. Kanwar, Lajpat R. Ahuja

Agricultural and Biosystems Engineering Publications

Increased level of NO3-N in the drinking water supplies is a major health concern these days. The long-term effects of actual nitrogen (N) fertilizer management practices are not well understood. The use of computer models allows the simulation of different N management practices on a long-term basis and their related effects on water quality. The RZWQM (Root Zone Water Quality Model, Version 3.0) was used to simulate the long-term (1978–1992) impacts of N management practices (single N applications at 50, 100, 150, and 200 kg per ha; and single and split N applications at 150 and ...


Effects Of Swine Manure Management Options On Groundwater Quality, Thad Hardeman Nov 1997

Effects Of Swine Manure Management Options On Groundwater Quality, Thad Hardeman

Proceedings of the Integrated Crop Management Conference

In 1994, there were 31 hog farms across the United States owning at least 10,000 sows and in 1995, there were 44 (Freese, 1994). This increasing number of large hog farms is evidence of the growing swine industry. This growth, however, has independent farmers, neighbors, environmentalists, and legislators in a quandary as to how the industry will evolve. These growing pains are of both an economic and environmental nature. Many topics need to be addressed as the production expands. One of the primary concerns of the growing hog industry is the issue of swine (Sus spp.) manure production.


Manue Application Effects On Residue, Odor, And Placement, H. Mark Hanna, Dwaine S. Bundy, Jeffery C. Lorimor, Steven K. Mickelson, Stewart W. Melvin Nov 1997

Manue Application Effects On Residue, Odor, And Placement, H. Mark Hanna, Dwaine S. Bundy, Jeffery C. Lorimor, Steven K. Mickelson, Stewart W. Melvin

Proceedings of the Integrated Crop Management Conference

Field experiments in no-till soybean and corn residue were conducted to evaluate six liquid swine manure application methods. The methods were injection with a conventional knife or sweep, incorporation with tandem disk after broadcast application, broadcast application, injection with a narrow-profile knife, and surface application behind row cleaners. The row cleaner and all injection treatments used finger-closing wheels. Air samples over the soil surface were obtained during and after application and residue cover was measured. Odor level was measured by the amount of air dilutions to reach odor threshold. Placement of material into the soil was evaluated with dye. Incorporation ...


The Role Of Water Stress In Creating Spatial Yield Variability In Soybeans, William D. Batchelor, Joel O. Paz Nov 1997

The Role Of Water Stress In Creating Spatial Yield Variability In Soybeans, William D. Batchelor, Joel O. Paz

Proceedings of the Integrated Crop Management Conference

Recent advancements in yield monitors and global positioning systems that can create spatial yield maps has generated much excitement and controversy among farmers and researchers. Site-specific field management promises to maximize field level net return and minimize environmental impact by managing fields using spatially variable management practices. The success of site-specific field management depends upon discovery of relationships between environment, management, and resulting yield variability, and ultimately, how these relationships can be exploited to compute optimum prescriptions. Farmers are faced with trying to determine how to manage variability to improve profits. Researchers are trying to develop methods to analyze causes ...


Iowa State University Extension Iowa Grain Quality Initiative, Darren Jarboe, Charles R. Hurburgh Jr. Nov 1997

Iowa State University Extension Iowa Grain Quality Initiative, Darren Jarboe, Charles R. Hurburgh Jr.

Proceedings of the Integrated Crop Management Conference

The worldwide emphasis on quality management is beginning to affect grain marketing in that users are identifying specific attributes that have additional economic importance. The Iowa Grain Quality Initiative (IGQI), a consortium of producer, industry, government and university experts, was formed to assist in the development of user-driven marketing strategies. Value-added grains, grains that exceed normal commodity grain in user performance or function, will present a wide range of challenges for producers and handlers, but represent potential value increases of 10-30 cents per bushel, more in very specialized applications.


Compost Quality Considerations For Crop Utilization, Tom L. Richard Nov 1997

Compost Quality Considerations For Crop Utilization, Tom L. Richard

Proceedings of the Integrated Crop Management Conference

Over the past several years compost production has increased dramatically in the agricultural, industrial, and municipal sectors. This expansion has been driven by increasing solid waste management costs, heightened public enthusiasm for organic matter recycling, and recognition that composting provides a way to manage manures and other organic solid wastes in an environmentally sound manner.


Tools For Value-Added Grain Marketing, Benjamin R. Winborn, Charles R. Hurburgh Jr. Nov 1997

Tools For Value-Added Grain Marketing, Benjamin R. Winborn, Charles R. Hurburgh Jr.

Proceedings of the Integrated Crop Management Conference

Grain producers face many decisions each year concerning the practices they will engage in and the products they will use. Markets for grains in the United States and the world over are changing. Due to the availability of affordable and reliable testing, the value of intrinsic characteristics like oil and protein can be realized at receiving points. Once identified and preserved, value-added grains can be directed to the best end use. Soybean processors are measuring protein and oil levels as reflected in higher value of oil and meal. As demand for value-added commodities increases in the United States, seed companies ...


Livestock Industry Facilities And Environment: Swine Breeding Systems—The Breeding Square System, Jay D. Harmon, Carl Watson Sep 1997

Livestock Industry Facilities And Environment: Swine Breeding Systems—The Breeding Square System, Jay D. Harmon, Carl Watson

Agriculture and Environment Extension Publications

The breeding square is arranged with four breeding pens that are surrounded by turn-around crates. The two sides of the square facing each other are the same sex animal. The corners hold the gilts in pens. The center is divided into four breeding pens, each 11 ft by 11 ft. This system is designed for twenty boars, twenty sows, and sixteen gilts.


Livestock Industry Facilities And Environment: Swine Cooling Methods—Evaporative Pads, Jay D. Harmon Sep 1997

Livestock Industry Facilities And Environment: Swine Cooling Methods—Evaporative Pads, Jay D. Harmon

Agriculture and Environment Extension Publications

Evaporative pads are porous pads that are mounted on the sidewall of a building, wet with water, either by running water down it from the top or by spraying water on it with nozzles, and then air is drawn through the pad. This process, called evaporative cooling, uses heat in the air to evaporate water, thereby reducing the air temperature but increasing the humidity.


Livestock Industry Facilities And Environment: Swine Cooling Methods—Sprinkling, Jay D. Harmon Sep 1997

Livestock Industry Facilities And Environment: Swine Cooling Methods—Sprinkling, Jay D. Harmon

Agriculture and Environment Extension Publications

Sprinkling is a cooling method in which pigs are sprinkled with water and then the water is allowed to evaporate. Evaporation of water removes heat from the skin surface of the animals, thereby making them feel cooler.


Livestock Industry Facilities And Environment: Swine Breeding Systems—The Levis System, Jay D. Harmon, Carl Watson Sep 1997

Livestock Industry Facilities And Environment: Swine Breeding Systems—The Levis System, Jay D. Harmon, Carl Watson

Agriculture and Environment Extension Publications

The Levis System was developed by Dr. Don Levis at the University of Nebraska. The basic concept is housing of sows and boars in separate rooms. To heat check, sows are walked into the boar room. Because they have not been exposed to boars on a continuous basis, sows in standing estrus will “lock up” immediately because they are more sensitive to boar stimuli. Pens or stalls may be used for gestation housing.


Livestock Industry Facilities And Environment: Swine Breeding Systems—Effects Of Heat Stress, Jay D. Harmon Sep 1997

Livestock Industry Facilities And Environment: Swine Breeding Systems—Effects Of Heat Stress, Jay D. Harmon

Agriculture and Environment Extension Publications

The thermal environment in the breeding facility plays an important role in total herd management. This manifests itself in poor conception and farrowing rates that may not be detected until weeks or months past the occurrence of an improper thermal environment. Because of this, it is important to anticipate these potential lulls in breeding performance and counteract them by managing the breeding facility environment properly and adding additional open females to keep the facilities full.


Livestock Industry Facilities And Environment: Swine Cooling Methods—Drip Cooling, Jay D. Harmon Sep 1997

Livestock Industry Facilities And Environment: Swine Cooling Methods—Drip Cooling, Jay D. Harmon

Agriculture and Environment Extension Publications

Drip cooling systems are used to drip water on the shoulder of sows or boars in a crated situation. This allows evaporation of the water which removes heat from the neck where a large blood supply is present. It is best used for systems where the animal is confined below the drip nozzle. In farrowing crate usage it has been shown to reduce sow respiration rate, increase feed consumption and improve litter weights.


Livestock Industry Facilities And Environment: Swine Breeding Systems—The Lubbock System, Jay D. Harmon, Carl Watson Sep 1997

Livestock Industry Facilities And Environment: Swine Breeding Systems—The Lubbock System, Jay D. Harmon, Carl Watson

Agriculture and Environment Extension Publications

The Lubbock System places weaned sows in crates with a boar placed in a pen directly behind them. Usually one boar is housed behind five or six sows. The boar pen is used not only to house the boar but for breeding. Females are backed into the breeding pen when estrus is detected. Generally all five sows are not from the same weaning group. This prevents the boar from being over-used.


Livestock Industry Facilities And Environment: Swine Breeding Systems—The Mo-Flex System, Jay D. Harmon, Carl Watson Sep 1997

Livestock Industry Facilities And Environment: Swine Breeding Systems—The Mo-Flex System, Jay D. Harmon, Carl Watson

Agriculture and Environment Extension Publications

The MO-Flex Swine Building System allows for any production stage (Farrowing, Nursery, Grow-Finish and Breeding/Gestation) to be built using the same structural building shell design.


Safe Farm: 1996 Iowa Farm Injury And Fatality Data By County, Charles V. Schwab, Laura J. Miller Sep 1997

Safe Farm: 1996 Iowa Farm Injury And Fatality Data By County, Charles V. Schwab, Laura J. Miller

Agriculture and Environment Extension Publications

Injury and fatality data are listed by hospitalized or not hospitalized, and work or leisure related.


Livestock Industry Facilities And Environment: Swine Cooling Methods—Stirring Fans, Jay D. Harmon Sep 1997

Livestock Industry Facilities And Environment: Swine Cooling Methods—Stirring Fans, Jay D. Harmon

Agriculture and Environment Extension Publications

Stirring fans are used to increase the air flow across animals during hot weather or to reduce temperature stratification in ventilated rooms. Stirring fans may be either the basket type or the ceiling fan type. Both have distinctive uses.


A Relative-Flux-Correction Scheme For Analyzing Three Dimensional Data Of A Tile-Drained Agricultural Plot, Binayak P. Mohanty Jul 1997

A Relative-Flux-Correction Scheme For Analyzing Three Dimensional Data Of A Tile-Drained Agricultural Plot, Binayak P. Mohanty

Agricultural and Biosystems Engineering Publications

The use of simple geostatistical tools is often constrained by data trend (nonstationarity) to characterize the spatial variability of soil properties in the subsurface environment influenced by any site-specific feature(s). Adaptive approaches, such as site-specific robust-resistant schemes, median polishing, trend analysis, etc., are thus used to preprocess the spatial data before analyzing for their spatial structures. Soil water nitrate–nitrogen (NO3–N) concentration (mg l−1) and soil moisture content (cm) data collected jointly from 175 sites arranged on a 5×7×5 three-dimensional (3-D) grid network of 7.6 m×7.6 m×0.3 m spacings ...


Use Of Ultimate Load Theories For Design Of Drilled Shaft Sound Wall Foundations, Matthew J. Helmers Jun 1997

Use Of Ultimate Load Theories For Design Of Drilled Shaft Sound Wall Foundations, Matthew J. Helmers

Matthew J. Helmers

A study was performed to investigate the factors that affect the accuracy of the procedures used by the Virginia Department of Transportation for design of drilled shaft sound wall foundations. Field load tests were performed on eight inch and nine inch diameter drilled shafts, and the results were compared to theoretical solutions for ultimate lateral load capacity. Standard Penetration Tests were run in the field and laboratory strength tests were performed on the soils from the test sites. It was found that published correlations between blow count and friction angle for sands and gravels can be used to estimate friction ...


The Cost Of Regulating Hog Manure Storage Facilities And Land Application Techniques, Bruce A. Babcock, Ronald A. Fleming, Dwaine S. Bundy Jun 1997

The Cost Of Regulating Hog Manure Storage Facilities And Land Application Techniques, Bruce A. Babcock, Ronald A. Fleming, Dwaine S. Bundy

CARD Briefing Papers

Much of the recent public concern over Iowa livestock production is focused on hogs, especially on the manner in which hog manure is stored and land applied. This report estimates the financial costs of implementing two regulations regarding the storage and disposition of manure: the first would require that all outside earthen storage basins and anaerobic lagoons be covered; the second would require that manure applied to crop acreage be immediately incorporated into the soil. The report also estimates the possible aggregate impact of the two regulations on the competitiveness of the Iowa hog industry.


Relevant Design Experiences For Agricultural And Biosystems Engineers: Team Focus Through Competition, D. Raj Raman, Ronald E. Yoder Jun 1997

Relevant Design Experiences For Agricultural And Biosystems Engineers: Team Focus Through Competition, D. Raj Raman, Ronald E. Yoder

D. Raj Raman

The multitude of specializations within biosystems engineering makes traditional capstone design courses, which typically focus on a single topic, less relevant. In our department, our year-long capstone design experience involves machine component design. While this experience is useful to students in all concentrations, ideally, students concentrating on biological-, food-, and soil and water-engineering will have a capstone design experience that integrates their unique technical capabilities. New capstone courses should also enhance the broader skills of undergraduate engineers, including teamwork, time and resource management, oral and written communication, and integrated computer skills. However, a variety of issues militate against simply adding ...


The Evolution Of An Introductory Biological Engineering Course: Design Is The Endpoint!, D. Raj Raman Jun 1997

The Evolution Of An Introductory Biological Engineering Course: Design Is The Endpoint!, D. Raj Raman

D. Raj Raman

Four the past four years, I have taught the sophomore level course, Agricultural Engineering 243 Material and Energy Flows in Biological Systems each spring semester. During the first offering, I used the lecture method to transmit information, and homework assignments and exams to reinforce skills and test comprehension. The greatest weakness of this technique seemed the lack of hands-on experience which I gave my students, and their subsequent lack of physical intuition. Enhancing their physical intuition drove the first curricular revision—using in-class demonstrations and simulations of key physical and biological processes. This technique did not work as well as ...


Have You Checked Your Grain Bin?, Charles R. Hurburgh Jr. Mar 1997

Have You Checked Your Grain Bin?, Charles R. Hurburgh Jr.

Agriculture and Environment Extension Publications

The problem is with low test weight corn that was either slow to mature or did not fully mature before it was harvested last fall. Corn with a high moisture content may have been dried to 13-14 percent last fall, but those readings might not be reliable.


Photoacoustic Measurement Of Unburned Carbon In Fly-Ash, David Waller, Robert C. Brown Jan 1997

Photoacoustic Measurement Of Unburned Carbon In Fly-Ash, David Waller, Robert C. Brown

Iowa State University Patents

The present invention provides a method and an apparatus for measuring the amount of unburned carbon in a sample of fly ash using infrared photoacoustic absorption. One preferred method according to the present invention involves directing modulated infrared radiation at a sample of fly ash and measuring the acoustic signal produced when the unburned carbon in the sample absorbs the radiation producing a thermal wave which propagates through the sample to generate a minute acoustic wave at interfaces between the carbon particles and gas surrounding the particles. One preferred apparatus includes a source of modulated infrared radiation, a chamber for ...


Reacting Interior Protein Of Grain To Fluoresce, Gerald Davis Christenbury, Wesley F. Buchele Jan 1997

Reacting Interior Protein Of Grain To Fluoresce, Gerald Davis Christenbury, Wesley F. Buchele

Iowa State University Patents

A method of measuring mechanical damage to a grain, such as corn, includes applying a reacting solution to a sample of corn. The solution contains a material, such as 8-anilino-1-naphthalene sulfonic acid, that reacts selectively with the damaged portion of the corn kernels, i.e., the internal protein that is exposed when the outer shell is penetrated or breached. Excess solution is washed off; and the kernels are dried for convenience of handling. The dried corn is ground to a uniform fineness and then spread over a predetermined area. What is inherently a three-dimensional or volume phenomena (damage) is converted ...


Aerodynamics Study Of The Flowfield At A Shelterbelt , Chien-Jung Yu Jan 1997

Aerodynamics Study Of The Flowfield At A Shelterbelt , Chien-Jung Yu

Retrospective Theses and Dissertations

Shelterbelts are used world-wide for such purposes as reduction of soil errosion, control of snow drift, and provision of an effective agrometeorological method of field microclimate management and yield enhancement. Whether performing a wind tunnel test, conducting a field observation, or implementing a numerical simulation to investigate shelterbelt effects, researchers are more interested in an optimum reduction in a thin air lasier near the ground on the leeside of the shelterbelt rather than total wind-speed reduction in the whole flowfield. The purpose of this study is to formulate a Navier-Stokes based scheme to simulate the turbulent aerodynamic characteristics of a ...


Development Of A Biofilm Bioreactor For Enhanced Propionic And Acetic Acid Production , Ferhan Ozadali Jan 1997

Development Of A Biofilm Bioreactor For Enhanced Propionic And Acetic Acid Production , Ferhan Ozadali

Retrospective Theses and Dissertations

Ten support materials including plastic-composite supports and six strains of propionibacteria were tested for their possible use in biofilm systems for enhanced production of propionic and acetic acid by fermentation. From screening experiments Propionibacterium thoenii strain P20 and fire bricks were chosen for further investigations;Propionibacterium thoenii P20 resists low-pH conditions, produces acid rapidly, forms luxuriant biofilms, and resists solvent inhibition better than other strains. Fire bricks are inexpensive, reusable, and compare favorably to commercial supports in ease of use and structural stability. A modified ilifesaveri shape for the individual fire brick particles was found to provide increased available surface ...


Design Of A Tractor Guidance System Using Simulation Trajectory Results Of Multibody Dynamic Program "Dads" , Elniema Mordos Moslim Jan 1997

Design Of A Tractor Guidance System Using Simulation Trajectory Results Of Multibody Dynamic Program "Dads" , Elniema Mordos Moslim

Retrospective Theses and Dissertations

Recent trends in agricultural industry indicate that automatic guidance of agricultural machines is indispensable for precision farming. The purpose of automatic guidance is to make the machine follow a prescribed path. A successful guidance system must be able to control the position of the machine to within a few centimeters;This study used two of the powerful software for design and analysis of mechanical and control systems, DADS and MATLAB. Also a Fortran code was written for the purpose of PMF system identification;First, DADS was used to model and perform tractor dynamic analysis. DADS animation feature was utilized to ...


Comparing Rolling Coulters Based On Soil Disturbance , Ravindra Dattatray Godbolé Jan 1997

Comparing Rolling Coulters Based On Soil Disturbance , Ravindra Dattatray Godbolé

Retrospective Theses and Dissertations

Rolling coulters are widely used as a leading element on modem conservation till planters. Few studies have predicted or measured how coulters interact with the soil and what soil conditions they create. This research was initiated to study and compare popular rolling coulter designs; bubble, plain, 8-wave and 25-wave, based on the soil disturbance they cause. Soil disturbance was measured in terms of surface disturbance using a photoscanning technique, surface roughness using soil profiles, and strength changes using cone index profiles. Testing was conducted in rototilled and no-till clay loam, and in compacted and loose clay and sandy soils. Soil ...


Classification Of Swine Thermal Comfort Behavior By Image Processing And Neural Network , Junqing Shao Jan 1997

Classification Of Swine Thermal Comfort Behavior By Image Processing And Neural Network , Junqing Shao

Retrospective Theses and Dissertations

In confinement swine production, environment controllers have conventionally been using air temperature as the standard, single control variable. Although the air temperature may be precisely controlled as designed, this method has its inherent drawbacks of not being interactive with the thermal needs of the pigs. Better performance of the animals may be achieved if the control is directly based on their thermal comfort behavior, which is not only affected by air temperature, but also by other thermal, social, and nutritional factors--floor type, air velocity, radiation, group size, etc;An interactive, behavior-based control scheme was thus proposed in this dissertation. This ...