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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

An evaluation of machine vs. hand harvest method for crisphead lettuce

Finch, Edwin Orville, 1937- January 1964 (has links)
No description available.
2

Development of a continuously moving three-level man positioning tree fruit harvesting aid.

Thorburn, George Alexander. January 1970 (has links)
No description available.
3

A study of mechanization alternatives in fruit harvesting

Yomchinda, Vitawas January 1970 (has links)
Fruit-growers in the lower mainland of British Columbia are facing a potential labor shortage for hand harvesting of fruit. Prices paid to hand picking labor have increased by more than 100 percent in the last three years. These factors have prompted interest in mechanical harvesting methods. The purpose of this research was to investigate the feasibility of introducing mechanical harvesting methods in raspberry production and to determine optimum machine parameters. A review of methods used for determining the optimum size of agricultural equipment was conducted and the methods were summarized. Due to the nature of small fruit production some commonly used methods were not applicable and modifications were necessary. A fruit yield function and a timeliness function were developed for Willamette raspberries. The fruit yield function based on actual yield data, was used for determining the potential income from a raspberry plantation. The timeliness function, based on the reduction of fruit quality due to variations in the length of the interval between subsequent harvests, was used to determine a suitable charge for untimeliness at any part of the harvest season. An optimum fruit removal efficiency for mechanical harvesting of Willamette raspberries was determined by assessing the loss in potential income due to the removal of green fruit and the production of over mature fruit. This was based on published results of mechanical harvesting trials. Results indicated that the mechanical harvesting of raspberries could be potentially much more profitable than hand harvesting. A machine with a fruit removal efficiency of 80 percent and with an operating speed of 1.5 miles per hour, or greater, appeared to be optimum. At operating speeds above 1.5 miles per hour, the cost of mechanical harvesting was not significantly influenced by the purchase price of the harvester. The cost of untimely operation was large. Extending the interval between subsequent harvests by one day resulted in an annual profit reduction of approximately 200 dollars per acre. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate
4

Development of a continuously moving three-level man positioning tree fruit harvesting aid.

Thorburn, George Alexander. January 1970 (has links)
No description available.
5

The mechanics of sugar beet lifting

Miller, P. C. H. January 1982 (has links)
No description available.
6

Harvesting lettuce by severing with a water jet

Schield, Michael Loyd, 1942- January 1972 (has links)
No description available.
7

Drying of conditioned hay in windrows as influenced by orientation of stems and environmental conditions.

Duggal, Devendra Singh. January 1969 (has links)
No description available.
8

Effect of microclimatic factors on the field drying of hay.

Lu, Fuming January 1971 (has links)
No description available.
9

A conceptual framework for the economic evaluation of water harvesting

Scrimgeour, Francis Gordon January 1989 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1989. / Includes bibliographical references. / Microfiche. / xiii, 145 leaves, bound ill. (some col.) 29 cm
10

An economic evaluation of water harvesting technology

Coupal, Roger H. January 1985 (has links) (PDF)
Thesis (M.S. - Agricultural Economics)--University of Arizona, 1985. / Includes bibliographical references (leaves 95-97).

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