Engineering Commons^™

Watershed Delineation In The Field: A New Approach For Mobile Applications Using Lidar Elevation Data, Samuel Adam Noel

Open Access Theses

With the advancement of mobile devices, opportunities to take watershed management tasks out of the office and into the field can be realized. In turn, field workers can utilize these technologies to expedite the decision-making process so that they may focus on meeting with clients and addressing agricultural watershed management issues. High-resolution (∼1.5 m postspacing) elevation data gathered by light detection and ranging (LiDAR) provides the topographic detail necessary to model hydrology at the field-scale (∼1 km2).

Non-artifactual surface depressions lead to erroneous surface flow patterns when using existing algorithms. So a sequential depression-filling algorithm (SDFA) has been developed to …

Using Energy-Efficient Technologies To Produce Bedding Plants And Microgreens In Protected And Controlled Environments, Joshua R. Gerovac

Open Access Theses

Gerovac, Joshua R. M.S., Purdue University, December 2014. Using Energy-Efficient Technologies to Produce Bedding Plants and Microgreens in Protected and Controlled Environments. Major Professor: Roberto G. Lopez. Production of bedding plants in commercial greenhouses (GHs) located in northern latitudes begins in late winter and continues through late spring when low outdoor temperatures generally necessitate active heating to maintain temperatures suitable for growth and development. Meanwhile, year-round production of microgreens using multi-layer systems requires sole-source (SS) photosynthetic lighting for production. Energy used to provide active heating in commercial GHs or SS lighting in multi-layer systems is second only to labor as …

Differences In Carbon Dioxide Evolution From Samples Of Shelled Corn Subjected To Various Storage Treatments, Cininta Alp Pertiwi

Open Access Theses

Shelled corn was collected from two sources - commercial grain elevators and corn harvested from Purdue University farms and then frozen until tested. Using a carbon dioxide (CO₂) test kit manufactured by Woods End Laboratories, CO₂ evolution measurements were conducted on shelled corn from both sources, after the samples were re-wetted to approximately 21% moisture content, placed in a 473 ml glass jar, and incubated at room temperature for 72 hours. The CO₂ test kit uses a gel that changes color in response to a change in the level of CO₂ in the surrounding air. …

Solvent System Selection For Xylooligosaccharides Separation By Centrifugal Partition Chromatography Using Conductor-Like Screening Model For Real Solvents, He Zhang

Open Access Theses

The production of value-added, bio-based industrial commodity chemicals is an important area in science right now and this study provides an initial step in the recovery of bio-based chemicals from hemicellulose. Hemicellulose is a long chain polymer mostly consisting of xylose, which is a five-carbon sugar, and a variety of other compounds that are ubiquitous in plant life. The hemicellulose polymer chain can be depolymerized into smaller components, called xylooligosaccharides (XOS) with different chain lengths of xylose linked by beta-1-4 glycosidic bonds, using either hot water, or dilute sulfuric acid. The xylooligosaccharides can then be purified from one another from …

Physical And Chemical Attributes Of A Genetically Modified Fruit Pectin, Carl Patrick Littrell

Open Access Theses

Pectin is an important polymer used in the food industry as a thickening and gelling agent. Though pectin is ubiquitous in plants, chemical and structural differences among pectin molecules prevent most from being viable for industrial use. Enzymes found naturally in fruit cell walls during the ripening process impair many desirable attributes of fruit pectins, rendering them unsuitable for industrial applications. Pectin methylesterase (PME) is one such enzyme whose expression can be altered during ripening through the use of recombinant genetic engineering. Reduction in levels of PME results in increased degree of methylation and molecular size of pectin, greatly increasing …

Sustainable Development Of Biogas Resources In East Africa Using Transdisciplinary Design Models, Christopher M. Limiac

Open Access Theses

Installation of anaerobic digestion systems in urban developing communities has the potential to address multiple problems related to energy and sanitation in a combined systems approach. Anaerobic digesters are used to generate a relatively clean and rich source of energy in the form of biogas to address energy poverty issues. The design resources available for anaerobic digestion projects must be improved to provide greater technical support and project transparency. In order to develop holistic solutions to grand challenges like energy poverty, engineers must be prepared to operate with the complexities of diverse environments. Globalization and the improvement of transdisciplinary project …

Design And Development Of A Novel Test Method To Measure The Slipper / Swashplate Interface Fluid Film In A Positive Displacement Machine, Natalie A. Spencer

Open Access Theses

Although robust models of fluid film behavior between the slipper / swashplate lubricating interface in positive displacement machines have been developed, measuring this same fluid film thickness to a highly accurate degree inside a relatively unaltered axial piston unit has never been accomplished until now. A test method was created to close this gap in available data by measuring fluid film thickness between the slipper and swashplate in a 130cc axial piston pump. Precise knowledge of the gap height between the slipper and swashplate at various shaft angle locations during operation provides critical insight into machine behavior. The design, validation, …

Quality Changes In Hermetically Stored Corn Caused By Fungi And Sitophilus Zeamais, Nda-Agyima Addae-Mensah K

Open Access Theses

Hermetic storage has been shown to be effective in controlling insect pests and maintaining grain quality of dry grains at 13% moisture and below. However, the feasibility and use of hermetic storage for grains at intermediate mid-moisture levels under the influence of the sub-Saharan African weather conditions is relatively unknown. Hermetic storage experiments were conducted on grade 1 "6297 and 6333 VT RIB" hybrid corn under controlled temperature conditions at 10 degrees centigrade and 25 degrees centigrade at target approximate moisture content levels of 11, 15, 18 and 21% wet basis for a total storage period of 6 months. Corn …

Developing An Unstructured Model To Investigate The Effect Of Ethanol On Product Yields For Glucose And Xylose Cofermentation In Saccharomyces Cerevisiae 424a (Lnh-St), Shane D. Clingenpeel

Open Access Theses

Production of bio-ethanol from lignocellulose requires the efficient fermentation of glucose and xylose, even in the presence of inhibitors. The desired product, ethanol itself, will inhibit the fermentation. A further understanding of how ethanol affects the organism is critical to overcoming its inhibition.

This thesis evaluated the effect of ethanol on the cofermentation of glucose and xylose in two different cases. The first case had an unstructured model created for Saccharomyces cerevisiae 424A (LNH-ST), a genetically modified strain of yeast capable of cofermenting glucose and xylose. The differential equations were based around sugar consumption, and the product yields were investigated …

A Farm Management Information System With Task-Specific, Collaborative Mobile Apps And Cloud Storage Services, Jonathan Tyler Welte

Open Access Theses

Modern production agriculture is beginning to advance beyond deterministic, scheduled operations between relatively few people to larger scale, information-driven efficiency in order to respond to the challenges of field variability and meet the needs of a growing population. Since no two farms are the same with respect to information and management structure, a specialized farm management information system (FMIS) which is tailored to the realities on the ground of individual farms is likely to be more effective than generalized FMIS available today.

This thesis presents the design of a FMIS using proven user-centered design principles. This approach resulted in the …