227 research outputs found

    Optimum cereal combine harvester operation by means of automatic machine and threshing speed control

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    The method by which automation of agricultural machinery can be developed is illustrated in the case of cereal combine harvesting. The controlled variables are machine forward speed and threshing cylinder peripheral speed. Four control systems have been developed that optimise these speeds on the basis of harvest costs minimisation, which includes variable and fixed costs of the machine and those of machine- and timeliness losses. The evaluated systems make use of a varying number of input process variables and control the machine speed exclusively, or both machine speed and threshing speed. The financial benefits from these control systems were calculated by means of a computer simulation. The research required in developing the models and control systems is discussed in detail. The simulation results demonstrate that control of low-frequency variations in crop properties brings some slight benefit and indicate that timeliness losses are of great importance to optimisation.<p/

    Agricultural Research Division 100th Annual Report, July 1, 1985, to June 30, 1986

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    This 100th Annual Report contains lists of current faculty, active projects, refereed journal publications, brief descriptions of research in selected areas, and the financial report for the period July 1, 1985, through June 30, 1986. Research programs in agriculture, home economics, and natural resources at the University of Nebraska have changed greatly since the U.S. Congress approved the establishment of an Agricultural Experiment Station in each state with the passage of the Hatch Act on March 2, 1887. Although Hatch funds account for a smaller proportion of the total research expenditures in the program today, this legislation continues to be an important source of funding for addressing priority problems that require long-term research projects. Faculty conducting research in agriculture, home economics, and natural resources in the University of Nebraska Institute of Agriculture and Natural Resources carry research appointments in the Agricultural Research Division. Most faculty are on joint appointments with teaching responsibilities in the College of Agriculture or the College of Home Economics or serve as extension specialists with appointments in the Cooperative Extension Service. As of June 30, 1986, the 136 full-time equivalents in the Agricultural Research Division were distributed among 200 faculty. The Agricultural Research Division faculty are located on the East Campus of the University of Nebraska in Lincoln and at the District Research and Extension Centers at Clay Center, Concord, North Platte, and Scottsbluff. The University of Nebraska Agricultural Researc

    Agricultural Research Division 100th Annual Report, July 1, 1985, to June 30, 1986

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    This 100th Annual Report contains lists of current faculty, active projects, refereed journal publications, brief descriptions of research in selected areas, and the financial report for the period July 1, 1985, through June 30, 1986. Research programs in agriculture, home economics, and natural resources at the University of Nebraska have changed greatly since the U.S. Congress approved the establishment of an Agricultural Experiment Station in each state with the passage of the Hatch Act on March 2, 1887. Although Hatch funds account for a smaller proportion of the total research expenditures in the program today, this legislation continues to be an important source of funding for addressing priority problems that require long-term research projects. Faculty conducting research in agriculture, home economics, and natural resources in the University of Nebraska Institute of Agriculture and Natural Resources carry research appointments in the Agricultural Research Division. Most faculty are on joint appointments with teaching responsibilities in the College of Agriculture or the College of Home Economics or serve as extension specialists with appointments in the Cooperative Extension Service. As of June 30, 1986, the 136 full-time equivalents in the Agricultural Research Division were distributed among 200 faculty. The Agricultural Research Division faculty are located on the East Campus of the University of Nebraska in Lincoln and at the District Research and Extension Centers at Clay Center, Concord, North Platte, and Scottsbluff. The University of Nebraska Agricultural Researc

    Laser Based Density Detection of Standing Wheat Stubble

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    Penetration of a laser beam through wheat stubble was used as a measure of stubble density. A low power, heliumneon laser was positioned perpendicular to travel direction. A photo detector was used to determine penetration duty cycle after the beam passed through the stubble. Penetration duty cycle measured on a simulated wheat crop gave a good indication of crop density. The laser beam appeared to penetrate the simulated crop at densities where direct transmission was blocked. Some reflection of the laser beam occurred through simulated wheat stalks and off the filter on the sensor. Tests in standing wheat stubble offered little indication that the detector could accurately indicate crop density. Correlataon coefficients between stalk density and detector readings ranged between 0.60 and 0.07. A statistical model was developed to describe the system and eliminate the affect of hidden stalks. The model demonstrated the insensitivity experienced at higher stubble densities.Agricultural Engineerin

    Institute of Terrestrial Ecology Annual Report 1984

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    Alternative Crops for Ethanol Fuel Production: Agronomic, Processing, and Economic Considerations

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    This report is a result of the fuel alcohol research team\u27s broadened focus during 1983. A comprehensive literature review was carried out to explore alternative starch and sugar crop alternatives for ethanol fuel production. Although the literature search was quite inclusive with respect to geographic regions, special emphasis was given to the agronomic and economic potential of various fuel alcohol crops in the Northern Plains region of the U.S., of which South Dakota is a part, and in LDCs of Asia, Africa, and Latin America. Our intent was to thereby determine possible energy crops deserving of more fuel alcohol research attention in the Northern Plains and also provide a document of use to ourselves and others considering various crops for fuel alcohol production in LDCs. Development assistance agencies, and universities such as SDSU which work with them, must be able to assess the energy producing potential of agricultural economies, along with food and fiber producing potentials. One kind of energy production that may be technically and economically feasible in some LDCs is fuel alcohol production from starch and sugar crops. (In this report, the terms alcohol and ethanol are used interchangeably.

    Biomass Wastes for Energy Production

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    Environmental problems are forcing a rethinking of the world’s energy supply system. In parallel, there is an increasing amount of global solid waste production. A fundamental shift toward greater reliance on biomass wastes in the world’s energy system is plausible because of ongoing major technological advances that hold the promise of making the conversion of biomass into high-quality energy carriers, like electricity and gaseous or liquid fuels, economically competitive with fossil fuels. Therefore, waste-to-energy systems have become a paramount topic for both industry and researchers due to interest in energy production from waste and improved chemical and thermal efficiencies with more cost-effective designs. This biomass shift is also important for industries to become more efficient by using their own wastes to produce their own energy in the light of the circular economy concept. This book on “Biomass Wastes for Energy Production” brings novel advances on waste-to-energy technologies, life cycle assessment, and computational models, and contributes to promoting rethinking of the world’s energy supply systems
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