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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.
21

Experimental study of elastoplastic mechanical properties of coke drum materials

Chen, Jie 06 1900 (has links)
Coke drums are vertical pressure vessels used in the delayed coking process in petroleum refineries. Significant temperature variation during the delayed coking process causes the useful life of coke drums to be shortened. In order to better understand the failure mechanisms, a experimental study of elastic/plastic mechanical properties and deformation behaviors of typical coke drum materials was performed. A new biaxial thermal-mechanical material testing system has been successfully developed. Basic characterization of mechanical properties of coke drum materials is achieved through uniaxial monotonic and cyclic loading tests. In addition, strain-rate dependence and creep of coke drum materials were further experimentally investigated. Complex thermal-mechanical cyclic tests were conducted. The experimental findings help us to understand the damage mechanisms of coke drums such as bulging. In addition, experimental data serve as benchmark data to verify the predictions of the temperature dependent elastoplastic constitutive model.
22

Evaluation of fisheries by-catch and by-product meals in diets for red drum (Sciaenops ocellatus)

Whiteman, Kasey 12 April 2006 (has links)
By-catch and wastes from processed fish and shrimp constitute a sizeable portion of commercial fishery landings. This discarded material is potentially valuable, for its content of fish meals and other substances. Fish meals, in particular, are increasingly in short supply for the manufacture of animal feeds, including feeds for farmed fish. Therefore, in this study, various by-catch and by-product meals of marine origin were evaluated with red drum (Sciaenops ocellatus), a carnivorous fish species native to the Gulf of Mexico that has been cultured over the past two decades for stock enhancement as well as for food. Four different kinds of by-catch or by-product meals [shrimp by-catch meal, shrimp processing waste meal, red salmon (Oncorhynchus nerka) head meal, and Pacific whiting (Merluccius productus) meal] were substituted for Special Select™ menhaden fish meal at two different levels (33% or 67% of crude protein) in prepared diets for red drum. Another treatment consisted of shrimp processing waste meal formulated on a digestible-protein basis to replace 33% of the protein from menhaden fish meal. Levels of calcium carbonate were reduced in two additional diets containing Pacific whiting, to evaluate the effects of ash content. Diets were formulated to contain 40% crude protein, 12% lipid, and 3.5 kcal digestible energy/g. Each diet was fed to triplicate groups of juvenile red drum in 38-l aquaria containing brackish water (7 ± 1 ppt) in two separate 6-week feeding trials. Survival, weight gain, feed efficiency, protein efficiency ratio and body composition responses were measured in each trial. Fish fed the by-catch meal at either level of substitution performed as well as fish fed the control diet containing protein solely from menhaden fish meal; whereas, fish fed the shrimp processing waste meal diets did significantly (P ≤ 0.05) worse than the controls, even when fed a diet formulated to be equivalent on a digestible-protein basis. Fish fed the red salmon head meal diet fared poorly, probably owing to an excessive amount of lipid in the diet that tended to become rancid. Overall, by-catch meal associated with shrimp trawling appears to be a very suitable protein feedstuff for red drum.
23

Replacement of Fishmeal with Plant Feedstuffs in the Diet of Red Drum Sciaenops ocellatus: An Assessment of Nutritional Value

Moxley, Joseph 2012 May 1900 (has links)
The expansion of aquaculture has increased demand for fishmeal supplies around the world; this, in turn, has resulted in dramatic increases in the cost of fishmeal, which has sparked interest in alternative feedstuffs. The development of new processing technologies, as well as the expanding generation of by-products from ethanol production has resulted in the development of novel protein sources that have the potential for replacing fishmeal in aquafeeds. The present study assessed the nutritional value of soy protein concentrate (SoyPC), barley protein concentrate (BarPC) and corn protein concentrate (CornPC) in the diet of red drum. Three sequential feeding trials were conducted; in these 50%, 75%, or 90% of the protein provided by Special SelectTM menhaden fishmeal in the reference diet was replaced with either SoyPC, BarPC, or CornPC in isonitrogenous (40% CP), isoenergetic (3.1kcal g-1) diets. Red drum with an average weight of 2.5 g, 1.6 g, and 1.5 g for trials 1, 2, and 3, respectively, were stocked in a recirculating system and fed twice daily at a rate approaching apparent satiation for 6 to 8 weeks. Along with the substitution of the selected plant feedstuffs, supplementation of DL-methionine and L-lysine was provided to exceed the established requirements of red drum for lysine and methionine, and glycine was added for palatability. Performance parameters of weight gain, feed efficiency, survival, hepatosomatic index, intraperitoneal fat ratio, and apparent digestibility coefficients for protein along with proximate composition of whole-body tissues were determined in the various trials. Results showed that 50% replacement of fishmeal protein by each of the protein concentrates produced fish performance, condition indices, and whole-body composition similar to those produced by the reference diet. However, replacing 75% and 90% of fishmeal protein with each of the plant protein concentrates reduced fish performance but not as severely as replacing all of the fishmeal protein with equal (33%) contributions from SoyPC, BarPC, and CornPC. Contrarily, these dietary substitutions did not reduce the apparent protein digestibility of the experimental diets. Based on the various results of this study, SoyPC, BarPC, and CornPC can readily replace 50% of the protein provided by menhaden fishmeal without adversely affecting the performance of cultured red drum.
24

Evaluation of fisheries by-catch and by-product meals in diets for red drum (Sciaenops ocellatus)

Whiteman, Kasey 12 April 2006 (has links)
By-catch and wastes from processed fish and shrimp constitute a sizeable portion of commercial fishery landings. This discarded material is potentially valuable, for its content of fish meals and other substances. Fish meals, in particular, are increasingly in short supply for the manufacture of animal feeds, including feeds for farmed fish. Therefore, in this study, various by-catch and by-product meals of marine origin were evaluated with red drum (Sciaenops ocellatus), a carnivorous fish species native to the Gulf of Mexico that has been cultured over the past two decades for stock enhancement as well as for food. Four different kinds of by-catch or by-product meals [shrimp by-catch meal, shrimp processing waste meal, red salmon (Oncorhynchus nerka) head meal, and Pacific whiting (Merluccius productus) meal] were substituted for Special Select™ menhaden fish meal at two different levels (33% or 67% of crude protein) in prepared diets for red drum. Another treatment consisted of shrimp processing waste meal formulated on a digestible-protein basis to replace 33% of the protein from menhaden fish meal. Levels of calcium carbonate were reduced in two additional diets containing Pacific whiting, to evaluate the effects of ash content. Diets were formulated to contain 40% crude protein, 12% lipid, and 3.5 kcal digestible energy/g. Each diet was fed to triplicate groups of juvenile red drum in 38-l aquaria containing brackish water (7 ± 1 ppt) in two separate 6-week feeding trials. Survival, weight gain, feed efficiency, protein efficiency ratio and body composition responses were measured in each trial. Fish fed the by-catch meal at either level of substitution performed as well as fish fed the control diet containing protein solely from menhaden fish meal; whereas, fish fed the shrimp processing waste meal diets did significantly (P ≤ 0.05) worse than the controls, even when fed a diet formulated to be equivalent on a digestible-protein basis. Fish fed the red salmon head meal diet fared poorly, probably owing to an excessive amount of lipid in the diet that tended to become rancid. Overall, by-catch meal associated with shrimp trawling appears to be a very suitable protein feedstuff for red drum.
25

Winter habitat use of fishes in the Ohio River

Lenz, Benjamin Ernst, January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains ix, 85 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references.
26

Inventing taiko

Carter, Carrie Alita. January 2013 (has links)
In the mid-1950s, Japan’s Daihachi Oguchi revived the taiko piece Suwa Ikaduchi, which had traditionally been played at the Nagano Prefecture Suwa Shrine. Until then, the song was played by a single male drummer for ritual at the shrine, a common use of Japanese drums throughout history. Oguchi made changes to the music, creating an ensemble of drums that emulated the Western drum kit, resulting in a new musical genre, which we now refer to as “taiko” in English. Nearly 60 years later, this musical form has spread across the globe with great popularity. The main points of this thesis are to clarify the distinct reference to an historic past required to discuss taiko within Hobsbawm’s theory of invented tradition, to present individuals and communities involved in the formalization of taiko, and to consider what can be learned from the ordinary musician. All of these lead to a better understanding of the process of the formalization, or metamorphosis of taiko, which has not previously been examined. Following the Introduction, Chapters One and Two provide background on both the instruments and the music of taiko. A survey of the inception of pioneer taiko groups in Japan and the United States, where taiko developed simultaneously, can be found in Chapter Four. The preceding Chapter Three presents new research regarding the community where the Suwa Ikaduchi score was discovered, and begins to consider the relationship between the taiko ensemble and the community in which it is formed. This connection between the taiko ensemble and community is reinforced by the story of Eitetsu Hayashi in the fifth chapter, a former member of one of Japan’s first professional taiko groups. Taiko is still developing as a music and a performance art, but we are able to draw conclusions about what is special about taiko in considering the relationship between taiko and community throughout these early years of development. The final chapter tells the stories of two non-professional taiko musicians, one in the United States and one in Japan, concluding that the “traditional” roots of taiko helped to develop a musical genre today with a purpose greater than the music itself. Appendix I includes a copy of the Suwa Ikaduchi drum score, instructions on how to read it using taiko’s system of oral transmission, and a chart explaining the basic rhythmic value of the system. A chronology of events in Japanese American history can be found in Appendix II. Appendix III includes figures of the different kinds of taiko, photos of the Osaka region’s danjiri, and newspaper articles printed during taiko’s formative years. / published_or_final_version / Music / Master / Master of Philosophy
27

Representations of African American Fife and Drum Music in North Mississippi

Danser, Kathleen Unknown Date
No description available.
28

Experimental study of elastoplastic mechanical properties of coke drum materials

Chen, Jie Unknown Date
No description available.
29

Mass Transfer Phenomena in Rotating Corrugated Photocatalytic Reactors

Xiang, Yuanyuan 18 December 2013 (has links)
Photocatalysis is a green technology that has been widely used in wastewater treatment. In this work, mass transfer processes in corrugated photocatalytic reactors were characterized both experimentally and through computer simulations. For the experimental work, various drum rotational speeds, reactor liquid volumes and number of corrugations were studied to elucidate their effects on mass transfer phenomena. The mass transfer rate was found to increase with increasing rotational speed. Liquid volumes in the reactor significantly affect the mass transfer rate when 20% of the surface area of the drum was immersed. A higher mass transfer rate was found using the drum with 28 corrugations, which had the lowest mass transfer coefficient when compared to the drums with 13 and 16 corrugations. In the computer simulations, velocity and concentration fields within the corrugated reactors were modelled to explore the characteristics of mass transfer processes. The mass transfer coefficients predicted by the simulations were lower than those measured experimentally due to mass transfer limitations occurring between the corrugation volume and bulk solution in the simulations. Based on mass transfer characteristics, it was determined that the drum with 28 corrugations was the most efficient photocatalytic reactor, and had the lowest mass transfer coefficient among those studied.
30

Melodic Drumming in Contemporary Popular Music: An Investigation into Melodic Drum-Kit Performance Practices and Repertoire.

Jordan, Michael, mjordan@iprimus.com.au January 2009 (has links)
This project is an investigation of melodic drum-kit practices in popular and contemporary music. The development of melodic drum-kit playing techniques has helped create a more inclusive role for drum-kit players within ensembles and has increased the potential for drum-kit players to present solo elements in performance. The project artefacts of my research are six compositions presented on CD. They demonstrate performance and compositional techniques that encourage a melodic approach to drum-kit performance. My research involved several methodological approaches these included: a) professional practice-based research, b) music composition and transcription, c) interviews with significant musicians familiar with drum-kit melodic practices and d) elements of autoethnography. I refer to particular drum-kit performance techniques and practices such as mirroring, thinking melodically, spatial relationships between drum-kit instruments and ensemble players, as well as, internalising melodic and harmonic ideas and being in the moment. I have shown in my compositional project that melodic elements in drum-kit performance and composition encourage a broader and more inclusive role for drummers in improvised performance. This is evident in the ensemble versions of compositions submitted as part of this study.

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