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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.
11

The performance and design of a mechanical cherry harvesting machine

Halderson, James L. January 1963 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1963. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 45-46).
12

Optimization of the performance of the cylinder type forage harvester cutterhead

Ige, Moses Toye. January 1975 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1975. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
13

Mechanical strawberry harvesting

Shikaze, George January 1973 (has links)
Total strawberry production in both Canada and the United States has been steadily declining for the past decade. This trend can, to a large extent, be attributed to the increasing cost and difficulty of getting this crop manually harvested. This research, therefore, is directed toward development of a mechanical harvesting system for strawberries. During initial development of any new concept, a system analysis should be undertaken to ensure that excessively complicated problems will not arise unexpectedly and to ensure that redundant research is not undertaken. Such an analysis indicated that the development of a once-over harvesting system is more feasible than the development of a selective harvesting system. The analysis also indicated that system development will require input from engineers, fruit growers, fruit processors and horticulturalists. An attempt is made to allocate appropriate areas of investigation and research to each of these groups. Group interactions are also investigated. To successfully develop the proposed system, one essential step is development of a mechanical picking machine. A design, based on the physical and mechanical properties of the strawberry fruit and plant, was used to build a picking -machine model. This model was field tested and evaluated. Limited field tests indicated that some field preparation for mechanical harvesting is essential and that a vacuum fruit pick up device should be considered to assist machine feeding. Tests indicated, however, that the proposed concept can be used to remove berries from the plant with very little fruit damage. / Land and Food Systems, Faculty of / Graduate
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14

Mechanical raspberry harvesting

Nyborg, Erling Orvald January 1970 (has links)
Raspberry growers in the lower mainland of British Columbia are contending with increasing production costs and are facing problems in obtaining seasonal labour for fruit picking. Since cost of hand harvesting represents a large proportion of the total production cost, the purpose of this research was to investigate the feasibility of mechanical raspberry harvesting and to design a mechanical harvesting system suitable for the lower mainland of British Columbia. A systematic design procedure, oriented toward design and testing of a bio-machine system, was employed and the selected design was based upon the physical and mechanical properties of the raspberry plant and its fruit. An economic analysis, comparing the mechanical harvesting system to present hand harvesting methods was used to determine the necessary relationships among machine cost, machine capacity and machine efficiency. The selected design for a mechanical raspberry harvesting system included tools for feeding, cane orientation, selective harvesting, fruit collection, fruit conveying and fruit storage. Mathematical models for these tools were constructed, based on a series of tests determining pertinent physical and mechanical properties of the raspberry plant and fruit. In addition, tests to define fruit quality were undertaken and the relationships among fruit quality and selective harvesting parameters were investigated. The use of chemical growth, regulator's to alter fruit retention force was also investigated. Force-deformation moduli, resulting from flat plate compression tests of raspberry fruit, were found to be good indicators of fruit quality. Correlations among force-deformation moduli and fruit properties indicated that either fruit retention force or F/W ratio could be used as control variables for a selective harvesting tool. Prototype units for feeding, cane orientation and selective harvesting tools were designed and fabricated. The selective harvesting tool was a fixed displacement shaker designed to apply equal maximum acceleration to all fruiting portions of the plant, independent of plant properties. F/W ratio was used as the control variable for selective harvesting. Limited field testing indicated that the tools for feeding, cane orientation and selective harvesting could satisfactorily be used in a mechanical raspberry harvesting system. Results also indicated that mechanical harvesting could be substantially more profitable than hand harvesting. The Willamette variety of raspberries as commonly grown in British Columbia was found not especially suitable for mechanical harvesting. Due to the high ratio of fruit retention force to fruit stem strength in the Willamette variety, the quality of machine harvested fruit must be lower than the quality of hand harvested fruit. Since fruit retention force is dependent upon fruit variety, investigation of physical properties of other suitable raspberry varieties should be undertaken in order to find a variety having properties more compatible with mechanical harvesting methods. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate
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15

Mathematical model for the selection of haying machinery

Jeffers, John Percival Weldon January 1966 (has links)
Surveys of hay harvesting machinery in the Lower Fraser Valley of British Columbia indicated wide variation in sizes of machines employed on farms of comparative size. Quality hay depends on 1. the types of forages grown 2. the stage of growth at which the crop is harvested and 3. the influence of weather as it effects curing. Bleaching, leaf shatter, and leaching of soluble nutrients are the worst hazards to which the crop is exposed. The system of harvesting will affect the time the crop is exposed to the effects of the weather. Methods that reduce the time needed for curing in the field tend to produce a better quality hay. Factors affecting the selection of least cost combinations of machines used in sequence are 1. the cost which bears a linear relationship to the capacity of the machines, 2. the area they have to service and 3. the time available for the performance of the operations. The time available for a sequence of operations to be performed in this case is a function of the weather. A study of the weather of the Lower Fraser Valley indicated that in any given ten day period during the months of June, July and August, the probabilities of two or more, three or more or four or more open days for field curing hay are constant. Using this linear cost capacity relationship, acreages from ten to one hundred acres, and the time available obtained from weather probability data, a mathematical model is derived to select least cost machinery combinations for hay harvesting in the Lower Fraser Valley. A computer programme for the I.B.M. 7040 digital computer is also developed. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate
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16

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.
17

Effect of microclimatic factors on the field drying of hay.

Lu, Fu-Ming January 1971 (has links)
No description available.
18

Maturity measurements of sweet corn.

Johnson, William Bradford 01 January 1951 (has links) (PDF)
No description available.
19

RainScapes

Daily, Cado, Wilkins, Cyndi 02 1900 (has links)
2 pp. / RainScapes are the ultimate in water efficient landscaping. RainScapes are beautiful landscapes that once established rely entirely on rain and stormwater (gray water too if available)while preserving tap water for indoor and drinking water needs.
20

Instrumented testing device for establishing crop condition

Corn, David January 2011 (has links)
Typescript. / Digitized by Kansas Correctional Industries

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