Browsing by Subject "Cotton -- Quality"
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Item Agronomic and economic evaluation of Bollgard cotton on the South Plains(Texas Tech University, 2002-05) Miller, Jeff WayneNot availableItem Assessment of trash content of cotton using 2D x-ray imagery(Texas Tech University, 2004-08) Dogan, Mehmet SerdarTrash content of raw cotton is a critical quality attribute. Therefore, its assessment is crucial for evaluating its processing and market value. Current technologies, including gravimetric and surface scanning methods, suffer from various limitations. Furthermore, worldwide, the most commonly used method still is human grading. Thus, the need for implementing new technologies is growing. One of the best alternatives to aforementioned approaches is x-ray imaging since it allows a thorough analysis of contaminants in a very precise and quick manner. In other work, we have successfully used x-ray tomographic imaging in the detection and classification of cotton contaminants. In this work, we choose to use x-ray radiographic imaging because of its real-time applicability. The segmentation of trash particles in 2D transmission images is difficult since the background cotton is not uniform. In addition, there is considerable overlap between the gray levels of subtle trash types and dense cotton. We dealt with this problem by characterizing and identifying the background cotton via scale-space filtering followed by a "background normalization" process that removes the background cotton successfully, while leaving the trash particles intact. Furthermore, we have successfully employed stereo x-ray vision for recovering the depth information of the piled trash in controlled samples. While adding to the accuracy with which the trash is counted, this method is much faster than the tomographic approach, as it requires only two projections. We tested our technique on 280 cotton radiographs—graded from 1 to 7 according to its trash content by expert graders—and compared the results with the existing systems of cotton trash evaluation. Results obtained with the proposed method were highly correlated with those obtained using the current systems. Given that the approach described here provides the trash mass in real-time, when realized, it will have a wide-spread usage in the cotton industry.Item Inheritance of fiber length mutants of upland cotton and relationships among lint yield, fiber quality, and economic indices(Texas Tech University, 2002-12) Moffett, Scott WThe narrow germplasm base of upland cotton iGossypium hirsutum L.) varieties grown on the Texas High Plains has historically been limited by relatively poor fiber quality. Prior work at Texas Tech University identified two chemically induced mutants (TTU 202 and TTU 271) that appeared to carry at least one partially dominant gene that increased fiber length. In 1998, a series of eight crosses were made with these two mutant lines and four established commercial cultivars (SC 9023, Holland 338, Explorer and Atlas) to determine the effectiveness of selection for fiber quality, lint yield and gross return in the segregating populations. Narrow-sense heritabilities, correlation coefficients and parent-offspring regression coefficients for HVI fiber quality, lint yield, loan value and gross return were also estimated. From their performance in the F3 and F4 generations, 56 lines that were among the top 25% for various indices were selected for: (1) superior fiber quality, lint yield and gross return (24 lines); (2) good fiber quality (11 lines); and (3) high lint yield and gross return (21 lines). These lines were advanced to the F5 generation where individual plants will be selected for additional testing. Parent-offspring Regression coefficients generated in this study showed that micronaire, fiber length, uniformity, and strength could be predicted from parental performance, while, loan value, lint yield and gross return could not be consistently predicted from the parental generation. In the F3 versus F2 generations, the highest narrow-sense heritability estimates were found in length (h^ 2n.s. = 0.10 to 0.59) and strength (h^ n.s. = 0.06 to 0.58). Micronaire, uniformity and loan value had heritability estimates ranging from h^ n.s. = 0.00 to 0.25. In the F4 versus F2 generation, fiber length had the highest heritability estimates (h^2 n.s. = 0.04 to 0.70). The heritability estimates of micronaire, uniformity, strength, and loan value ranged from h^2 n.s. = 0.00 to 0.28. In the F4 versus F3 generations, length had the highest heritability estimates (h n.s. = 0.33 to 0.76). Micronaire, uniformity and strength had intermediate heritability estimates (h^ n.s. = 0.05 to 0.66), while loan value, lint yield and gross return had low heritability estimates (h^ n.s. = 0.00 to 0.16). Results of individual correlation analyses on all crosses, the parent varieties and a collection of commercial cultivars showed there was a positive and significant correlation between lint yield and gross return (r = 0.86** to 1.00**). The impact of fiber length on loan value; strength on loan value; micronaire on loan value; length on strength; micronaire on length; and micronaire on strength had a wide range of variation in the correlation coefficients. The correlation and for loan value on gross return; fiber length on gross return; strength on gross return; micronaire on gross return; lint yield on loan value; fiber length on lint yield; strength on lint yield; and micronaire on lint yield, were mostly negative and inconsistent. The cross of SC 9023 X TTU 202 was the only cross to show a positive, significant correlation between fiber length and gross return (r = 0.37**) and fiber length on lint yield (r = 0.25**). These results indicate that selection in crosses between commercial cultivars and two enhanced fiber mutants evaluated in the study could improve fiber quality, lint yield and gross return in High Plains Cotton. The heritability estimates of micronaire, fiber length, uniformity, and strength show potential for improvement of these traits through selection. The highly positive, significant correlations showed that lint yield was the most important factor in determining gross return; fiber length and strength were the most important factors in determining loan value.Item Optimization of fiber quality, production rate, and lint turnout for the powered roll gin stand utilizing response surface methodology and desirability functions(Texas Tech University, 2004-12) Holt, Gregory AlanThe power roll gin stand is a new saw gin technology developed at the United States Department of Agriculture - Agricultural Research Service's cotton ginning laboratory in Lubbock, Texas. The technology was initially developed to regin cottonseed to solve processing problems with a cottonseed coating process (Easiflo™). Evaluation of the fiber properties from reginning the cottonseed indicated the potential for this technology to be utilized for ginning seed cotton. Since then, numerous studies have been conducted evaluating the power roll gin stand's potential for ginning seed cotton. Past results have shown increased production and lint turnout without adversely affecting fiber properties and in some cases improvements in fiber properties over conventional gin stands were demonstrated. However, a majority of the initial studies were conducted at operational settings that were optimal when reginning cottonseed and not seed cotton. The power roll gin stand consists of three main components: paddle roll, saw, and seed finger roll. The operational settings of speed and/or loading rate at which these components operate influence fiber properties and/or processing rate, items which are important to either the producer, cotton gin management, and/or textile mills. This dissertation reports on two studies, on different makes of gin stands, to optimize the power roll gin stand's operational components for optimal production rate, lint turnout, and fiber properties in the ginning of seed cotton. The optimizations were performed using response surface methodology and desirability functions. Since the power roll gin stand is a new technology, understanding how the various components of the gin stand can be manipulated to enhance operational performance while preserving fiber properties is paramount to successful implementation of this technology in the cotton ginning industry. The first study consisted of a prototype Lummus-116 gin stand located at the United States Department of Agriculture - Agricultural Research Services gin lab in Lubbock, Texas. The second gin stand was installed in a commercial cotton gin and operated during the 2003 ginning season in Courtland, Alabama. Results from the studies produced several optimal solutions depending on the response variables evaluated and the weighting factors used in the desirability functions. Once the optimization studies were completed, validation and comparison studies were conducted. Validation studies evaluated the results obtained from the optimization studies while the comparison tests were performed versus conventional gin stands to see if the optimized gin stand performed to expectations. Results from these studies indicated some improvements over conventional gin stands in fiber properties, lint turnout, and/or processing rate. Overall, the power roll gin stand has demonstrated the potential for improvements in processing rate, lint turnout, and preserving fiber properties. Likewise, the power roll gin stand has the potential to be utilized in real-time process control applications where the gin stand is dynamically adjusted to produce optimum fiber properties based on the quality of the seed cotton being ginned. Being able to dynamically adjust the gin stand while ginning seed cotton allows the possibility of "prescription ginning" at the very heart of the cotton gin, the gin stand.Item U.S. textile mill manufacturers' valuation of cotton quality attributes(Texas Tech University, 1995-08) Chen, ChangpingThe innovation and adoption of the High Volume Instrument grading system present the U.S. cotton industry with both new opportunities and challenges. While more accurate information about cotton quality is available for market participants, the understanding and comprehension of the price-quality relationships under the new grading system have increased importance in production, marketing, and use of cotton. This study analyzed and determined the patterns of the market values paid by U.S. textile mills for cotton fiber attributes. Hedonic price models, based on Rosen's analytical framework, were developed to analyze the information of bona fide market transactions in the textile mill market for the U.S. as a whole and three individual U.S. cotton regions during the period 1992-1995. These models explained how fiber attributes (i.e., trash content, color, staple, strength, micronaire), and other nonfiber factors affected cotton prices. Results suggest that textile mill manufacturers paid different premiums and/or discounts for different fiber attributes for each individual region in the U.S. The textile mill industry seems to differentiate cotton by the region of origin in both fiber premiums and/or discounts and base prices. Fiber premiums and discounts are substantially different between the West and South Central region. Staple premiums and discounts were significantly different between the West and the South. Micronaire discounts differed across all three regions. Textile mill manufacturers only paid strength premiums for the cotton produced in the Western region. This analysis provides the market participants with information relevant to government cotton programs, cotton preparation, variety selection, and cotton marketing strategies. It also demonstrates methods for collecting and analyzing hedonic market data collected from individual firms.Item X-ray microtomographic image analysis for identification of cotton contaminants(Texas Tech University, 2002-08) Pai, Ajay STechnologies currently used for cotton contaminant assessment suffer from some fundamental limitations. These limitations severely restrict the ability of existing technologies to accurately detect and classify contaminants in cotton. Such inaccuracies result in the misassessment of the cotton quality, and have a serious impact on its economic value. The fundamental limitations of existing methods include the inability to detect contaminants under the surface of cotton, the inability to accurately measure shapes and sizes, sample preparation requirements, and poor spatial resolution. These limitations may be easily overcome by the use of x-ray tomographic imaging, which allows for highly accurate imaging of the internal features of an object in a non-destructive fashion. This thesis describes in detail the design of a GUI based interactive cotton contaminant analysis tool. Through the use of an x-ray microtomographic scanner and image processing algorithms, it is shown that x-ray tomographic imaging can provide very accurate information regarding shape, size, and density of cotton contaminants. This information has been analyzed using a fuzzy-logic-based classification scheme to create a highly accurate contaminant analysis tool. Despite its obvious advantages, x-ray imaging does have some drawbacks, principle among which pertains to the time taken to perform the procedure. These drawbacks, along with possible solutions have also been discussed in this thesis. It is our firm belief, however, that if realized in real-time, this procedure will have a definite impact on the cotton cleaning process, and indeed on the economic value of cotton.