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Swanson, G. A.; Haley, M. (Energy Systems Laboratory (http://esl.tamu.edu)Texas A&M University (http://www.tamu.edu), 2005)[more][less]
Abstract: If your company is looking at energy management as part of its overall strategy to reduce costs and improve profits, it is not alone. While energy prices have increased at a shocking rate, so has interest in environmental responsibility. Progressive organizations are exploring ways to conserve energy and reduce greenhouse gases. Some are even creating new positions for these issues, placing someone in charge of corporate social responsibility (CSR). The CSR's job is to help a company be more socially responsible and reduce harmful emissions. Energy management can accomplish both conservation and emission goals- plus, it lowers utility costs and strengthens your bottom line! In the past, reasonably priced energy made it difficult to justify new conservation projects. It was hard to meet the standard criteria of 2-3 years payback. However, natural gas prices have tripled in the last five years from $2 to over $6 per Dekatherm (Dth). Electric prices also have increased dramatically-by more than 100% in some parts of the country. These increased energy costs have made conservation projects more desirable. A natural gas improvement project that had a six-year payback five years ago may have less than a two-year payback today. New technologies also have helped drive down the payback of projects and opened up new areas for potential savings. The following paper looks at how the new market offers opportunities to reduce overall energy costs. URI: http://handle.tamu.edu/1969.1/5605 Files in this item: 1
ESL-IE-05-05-44.pdf (365.0Kb) -
Jung, Jae Won, 1969- (Texas A&M University, May 2003)[more][less]
Abstract: A beta-emitting glass seed was proposed for the brachytherapy treatment of prostate cancer. Criteria for seed design were derived and several beta-emitting nuclides were examined for suitability. 142Pr was selected as the isotope of choice. Seeds 0.08 cm in diameter and 0.9 cm long were manufactured for testing. The seeds were activated in the Texas A&M University research reactor. The activity produced was as expected when considering the meta-stable state and epi-thermal neutron flux. The MCNP5 Monte Carlo code was used to calculate the quantitative dosimetric parameters suggested in the American Association of Physicists in Medicine (AAPM) TG-43/60. The Monte Carlo calculation results were compared with those from a dose point kernel code. The dose profiles agree well with each other. The gamma dose of 142Pr was evaluated. The gamma dose is 0.3 Gy at 1.0 cm with initial activity of 5.95 mCi and is insignificant to other organs. Measurements were performed to assess the 2-dimensional axial dose distributions using Gafchromic radiochromic film. The radiochromic film was calibrated using an X-ray machine calibrated against a National Institute of Standards and Technology (NIST) traceable ion chamber. A calibration curve was derived using a least squares fit of a second order polynomial. The measured dose distribution agrees well with results from the Monte Carlo simulation. The dose was 130.8 Gy at 6 mm from the seed center with initial activity of 5.95 mCi. AAPM TG-43/60 parameters were determined. The reference dose rate for 2 mm and 6 mm were 0.67 and 0.02 cGy/s/mCi, respectively. The geometry function, radial dose function and anisotropy function were generated. URI: http://handle.tamu.edu/1969.1/5738 Files in this item: 1
etd-tamu-2007A-NUEN-Jung.pdf (2.847Mb) -
Hoskins, Sara Grace (Texas A&M University, December 2003)[more][less]
Abstract: Within the collections of the Museu de Angra do Heroismo (Terceira Island, Azores, Portugal) are nine cast bronze guns from the 16th century. Most were raised from the seafloor between the 1960s and 1990s, but this study comprises the first in-depth research into their design and manufacture. The importance of this kind of study lies in the fact that ordnance is commonly found on shipwrecks of this time. A greater knowledge of guns will help provide information about the ships from which they came. Careful documentation and study of the Museu de Angra cannon will add greatly to their value as museum exhibits, by allowing museum patrons to better understand where the guns came from, how they were cast, and why they were important. This documentation adds to our knowledge of Western European gunfounding technology during the sixteenth century, as four different countries commissioned the guns: Portugal, Spain, France, and England. With detailed documentation and publication, the Museu de Angra bronze guns can be added to the bibliography of ordnance of this period, which will aid future researchers who encounter similar pieces. The Museu de Angra bronze guns, as symbols of the military and naval power of the countries that commissioned them, were sent aboard ships, into the field, and mounted on fortress walls. Bronze guns of this time period are particularly important, as bronze was an expensive commodity, and the demand for ordnance was increasing rapidly. Countries developed more effective ways to make use of iron for the founding of guns, and the use of bronze became more symbolic of wealth. The information that each gun contains includes both the cutting-edge military technology of the time and the artistic statement of the founder. Some of the finest metalwork of the period was displayed in cast bronze guns, and due to the founding techniques, no two are the same, making each an important piece of history. URI: http://handle.tamu.edu/1969.1/556 Files in this item: 1
etd-tamu-2003C-ANTH-Hoskins-1.pdf (10.11Mb) -
Ward, Ruby; Chen, Chi Chung; McCarl, Bruce A.; Keplinger, Keith O. (Texas Water Resources Institute, February 1998)[more][less]
Abstract: The EAA implemented a pilot irrigation suspension program in 1997 on 9,669 acres mainly in Medina and Uvalde counties with the objective of increasing springflow at Comal Springs, and providing relief to municipalities in meeting Critical Period (drought) Management Rules. The Aquifer region, however, experienced a wet Spring in 1997, so that even irrigators not enrolled in the program applied little or no irrigation water. If conditions were dry in Spring 1997, aquifer simulation results indicate that suspending irrigation on enrolled acreage would have reduced pumping by 23,206 acre-feet and would have augmented Comal springflow by 6,498 acre-feet during the program year and by 17.7 cfs in August. The level of the eastern portion of the Aquifer would have been expect to rise by about 3.8 feet, and the cost per acre-foot of suspended irrigation would have been about $99. Payments to irrigators totaled $2,350,000. The ISP Program did cause farmer adjustments. Participants in the ISP program planted less corn, cotton, vegetables, and peanuts in favor of more sorghum and wheat. Irrigators who converted to dryland purchased somewhat less fertilizer, seed, and labor, but secondary effects on the local economy appeared to be small. The price paid per suspended acre was much higher than regional lease rates and average cropping profit margins in many instances. Factors which may have accounted for the high bids include: 1) lack of experience with an ISP, 2) its late start up, 3) the belief that bids might affect future water prices or offers, 4) tendencies to bid high enough to cover costs under a worst case scenario of a total loss of dryland crops, 5) collusion and need to bid high enough to compensate all under current land lease arrangements. Bids in future ISP solicitations might be lower, or might not. Given the substantial difference between local irrigated land rental rates and ISP bids, it seems unlikely that the EAA could attract sufficient acreage by capping bids at rental rates. There may be, however, some latitude for the EAA to set a maximum per acre rate somewhere between local rental rates and the ISP bids. This, combined with announcing the program and executing contracts in October or November, has the possibility of substantially reducing program cost. The EAA may also want to consider offering an option contract which when implemented would suspend irrigation in April or May. Waiting until April or May would provide the EAA more information on current year weather allowing better information on whether irrigation suspension is really necessary since: 1) more time would have elapsed allowing administrators to know Aquifer elevation at a later date, and 2) information of weather, irrigation use to date and projected irrigation for the remainder of the cropping year is increased this point. The cost of a single implementation of such a program may be substantially higher than a January 1 contract, since irrigators may sustain greater loss. Expected program cost, however, could be lower, since this option would be exercised less frequently, offsetting over higher cost of implementation. Good alternatives to an ISP are limited. We evaluated the potential of 1) implementing more efficient irrigation technology and 2) buying land and leasing it back during wet or average years. The ISP is a more cost effective source of critical water than is the use of subsidized irrigation efficiency largely because the ISP can put in place only when water is needed. Also, while not considered here, evidence in areas such as the High Plains suggests that irrigator pumping is not reduced by the amount an increase in irrigation efficiency would imply. This is because irrigators may choose to irrigate more water intensive crops and/or irrigate more acreage when efficiency is increased. The high bids experienced in the 1997 program compared to price of land in the Aquifer region suggests that a buy-leaseback arrangement could substantially reduce the cost to the EAA of suspending irrigation. This, of course, would require an alternate set of administrative costs by the EAA and may be less expensive than the ISP. Also the picture may be altered by the adjudication of water rights in the Aquifer which will likely be finished within three to five years. After water rights adjudication, however, buying and leasing back water rights may be a very appropriate and cost effective strategy for the EAA. In sum, we conclude that the 1997 pilot ISP was a reasonable response to the drought condition experienced in 1996. Fine-tuning the selection criteria, bid arrangement, allowing greater lead time, and/or implementing an ISP or option contract later in the year, holds the potential for reducing the cost of program implementation. A land-based ISP is an interim arrangement that can be implemented in the absence of a fully functioning permit system. After water rights are adjudicated in the region, ISP and option contracts will take on more conventional forms involving buy, lease, and option contracts for water rights. It is expected that water-based versus land-based arrangements would likely facilitate the transfer of water at lower rates. URI: http://hdl.handle.net/1969.1/6152 Files in this item: 1
tr178.pdf (244.9Kb) -
Stefanou, Nikolaos, 1978- (Texas A&M University, May 2006)[more][less]
Abstract: Hard disk drive applications require a high Spurious Free Dynamic Range (SFDR), 6-bit Analog-to-Digital Converter (ADC) at conversion rates of 1GHz and beyond. This work proposes a robust, fault-tolerant scheme to achieve high SFDR in an av- eraging flash A/D converter using comparator chopping. Chopping of comparators in a flash A/D converter was never previously implemented due to lack of feasibility in implementing multiple, uncorrelated, high speed random number generators. This work proposes a novel array of uncorrelated truly binary random number generators working at 1GHz to chop all comparators. Chopping randomizes the residual offset left after averaging, further pushing the dynamic range of the converter. This enables higher accuracy and lower bit-error rate for high speed disk-drive read channels. Power consumption and area are reduced because of the relaxed design requirements for the same linearity. The technique has been verified in Matlab simulations for a 6-bit 1Gsamples/s flash ADC under case of process gradients with non-zero mean offsets as high as 60mV and potentially serious spot offset errors as high as 1V for a 2V peak to peak input signal. The proposed technique exhibits an improvement of over 15dB compared to pure averaging flash converters for all cases. The circuit-level simulation results, for a 1V peak to peak input signal, demon- strate superior performance. The reported ADC was fabricated in TSMC 0.18 ??mCMOS process. It occupies 8.79mm2 and consumes about 400mW from 1.8V power supply at 1GHz. The targeted SFDR performance for the fabricated chip is at least 45dB for a 256MHz input sine wave, sampled at 1GHz, about 10dB improvement on the 6-bit flash ADCs in the literature. URI: http://handle.tamu.edu/1969.1/2469 Files in this item: 1
etd-tamu-2005A-ENGR-Stefanou.pdf (1.120Mb) -
Garrison, M. (Energy Systems Laboratory (http://esl.tamu.edu)Texas A&M University (http://www.tamu.edu), 2006)[more][less]
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Klinefelter, Danny A. (March 26, 2009)[more][less]
Abstract: Farm income in 2009 will likely decline from previous years, and the value of rural land is likely to flatten out also. Producers need to increase their emphasis on financial and risk management. Description: 2 pp. URI: http://handle.tamu.edu/1969.1/87601 Files in this item: 1
pdf_2712.pdf (767.8Kb) -
Ayala, Julio Enqrique, II, 1979- (Texas A&M University, December 2005)[more][less]
Abstract: Recently, there is a growing interest in applying electronic circuit design for biomedical applications, especially in the area of nuclear magnetic resonance (NMR). NMR has been used for many years as a spectroscopy technique for analytical chem- istry. Previous studies have demonstrated the design and fabrication of planar spiral inductors (microcoils) that serve as detectors for nuclear magnetic resonance mi- crospectroscopy. The goal of this research was to analyze, design, and test a prototype integrated sensor, which consisted of a similar microcoil detector with analog components to form a multiple-channel front-end for a magnetic resonance imaging (MRI) system to perform microspectroscopy. The research has succeeded in producing good function- ality for a multiple-channel sensor. The sensor met expectations compared to similar one-channel systems through experiments in channel separation and good signal-to- noise ratios. URI: http://handle.tamu.edu/1969.1/4729 Files in this item: 1
etd-tamu-2005C-ELEN-Ayala.pdf (1.933Mb) -
Kaltenberg, Amanda May, 1980- (Texas A&M University, December 2004)[more][less]
Abstract: A hull-mounted 38-kHz phased-array acoustic Doppler current profiler (ADCP) was used to acoustically survey the continental margin of the northern Gulf of Mexico (GOM) during 6 cruises in 2002-2003. This is the first backscatter survey with a 38-kHz ADCP in the Gulf of Mexico. ADCPs have been used as a proxy to measure the volume backscatter return from plankton in the water column, however previous studies were restricted to the upper 200 to 300 meters due to the relatively high frequency of operation (150-300 kHz) of the transducers. In addition to measuring deep water current velocities, the 38-kHz phased-array ADCP can measure Relative Acoustic Backscatter Intensity (RABI) as deep as 1000 meters. The daytime depth of the main deep scattering layer at 400 to 500 meters was resolved, and locally high backscatter intensity can be seen down to 800 meters. The objectives were to determine how to analyze RABI from the instrument to resolve scattering layers, and then to seek secondary deep scattering layers of potential prey species below the main deep scattering layer, from 600 to 800 meters in the feeding range for Gulf of Mexico sperm whales. Based on RABI from the 38-kHz ADCP, secondary DSLs in sperm whale diving range were more commonly recorded over the continental shelf than in the deep basin region of the Gulf of Mexico. The daytime depths of migrating plankton showed variation depending on physical circulation features (cyclone, anticyclone, proximity to Mississippi river, and Loop Current) present. Vertical migrations compared between concurrently running 38 and 153-kHz ADCPs showed an overlap of acoustic scatterers recorded by the two instruments, however the 153-kHz instrument has much finer vertical resolution. Vertical migration rates were calculated and simultaneous net tow samples from one of the cruises was used to compare abundance estimates by the two methods. URI: http://handle.tamu.edu/1969.1/1387 Files in this item: 1
etd-tamu-2004C-2-OCNG-Kaltenbe.pdf (1.442Mb) -
Zhuang, Wei, 1974- (Texas A&M University, May 2003)[more][less]
Abstract: A three dimensional (3-D) capacitance extraction algorithm based on a kernel independent hierarchical method and geometric moments is described. Several techniques are incorporated, which leads to a better overall performance for arbitrary interconnect systems. First, the new algorithm hierarchically partitions the bounding box of all interconnect panels to build the partition tree. Then it uses simple shapes to match the low order moments of the geometry of each box in the partition tree. Finally, with the help of a fast matrix-vector product, GMRES is used to solve the linear system. Experimental results show that our algorithm reduces the linear system's size greatly and at the same time maintains a satisfying accuracy. Compared with FastCap, the running time of the new algorithm can be reduced more than a magnitude and the memory usage can be reduced more than thirty times. URI: http://handle.tamu.edu/1969.1/5794 Files in this item: 1
etd-tamu-2006A-CEEN-Zhuang.pdf (1.740Mb) -
Malagon Nieto, Camilo, 1978- (Texas A&M University, May 2003)[more][less]
Abstract: The complex interrelations among the different physical processes involved in acid fracturing make it difficult to design, and later, to predict the outcome of stimulation jobs. Actual tendencies require the use of computational models to deal with the dynamic interaction of variables. This thesis presents a new study of acidized surface textures by means of a laser profilometer to improve our understanding of the remaining etched surface topography and its hydraulic response. Visualization plots generated by the profilometer identified hydrodynamic channels that could not be identified by the naked eye in acidized surfaces. The plots clarified the existence of rock heterogeneities and revealed how the processes of dissolution function in chalk rock. Experimental data showed clearly that the effect of dissolution depends on the type of rock and the fluid system; dolomite, for example, dissolves more rapidly but more roughly than limestone. Fluid leakoff rate and temperature also affect the dissolution. Further research is necessary to clarify the effects of conductivity. URI: http://handle.tamu.edu/1969.1/5771 Files in this item: 1
etd-tamu-2007A-PETE-Malagon.pdf (35.27Mb) -
Anderson, Christopher Dean, 1979- (Texas A&M University, December 2003)[more][less]
Abstract: The purpose of this project is to develop a software framework, a 3D engine, which will generate images to be projected onto facets of a spatially immersive display (SID). The goal is to develop a software library to support the creation of images of specified 3D environments which are specific to the display geometries of a polyhedral class of SIDs. Part of this goal is developing auxiliary software to allow this library to be thoroughly tested. When properly working, the images being displayed on adjoining faces of the SID appear spatially and temporally consistent with one another, creating the illusion that the user is within a surrounding three-dimensional space. URI: http://handle.tamu.edu/1969.1/1307 Files in this item: 1
etd-tamu-2003C-VIZA-Anderson-1.pdf (2.118Mb) -
Lau, Ryan, 1981- (Texas A&M University, May 2003)[more][less]
Abstract: Relatively little is known about marine controlled-source electromagnetic surveys (MCSEM) used to detect hydrocarbon reservoirs. Typical MCSEM require the use of inversion to generate a model of the subsurface. We utilize a 3D finite-element forward model to simulate a MCSEM survey. With the results we were able to determine the strengths and weaknesses of each transmitter and receiver configuration that would best detect a shallow hydrocarbon target. Careful selection of the correct configuration is important as we have found that incorrect transmitter orientation, offset and receiver measurement component can yield misleading results. Using the ideal configuration we were able to directly image the hydrocarbon target without the use of inversion modeling. The direct image is able to show the hydrocarbon target's shape and edges without any ambiguity. The direct image of the target can potentially be used to refine 3D inversion modeling, or be used in conjunction with seismic profiles to refine seismic picks. URI: http://handle.tamu.edu/1969.1/5790 Files in this item: 1
etd-tamu-2006A-GEOP-Lau.pdf (384.0Kb) -
Naz, Asma, 1971- (Texas A&M University, December 2004)[more][less]
Abstract: The objective of my research is to revive and practice the art of traditional pictorial maps in 3D cartographic visualization. I have chosen to create both graphical and statistical pictorial maps which can be used for the purpose of tourism and data representation respectively. Some traditional hand-drawn and sculptural pictorial maps of famous artists have been picked out to start as a base for my work. The goal was to recreate or imitate the style, character and features of these traditional hand-drawn and sculptural maps with 3D computer graphics and to analyze how effectively 3D tools can be used to communicate map information. I also wanted to explore ways to make these maps interactive on the Web and have them accessible to a large number of viewers. The results show a number of interactive 3D pictorial maps of different countries and continents. These maps are initially built with Maya, a 3D modeling software, and converted into web pages using the Viewpoint Technology. For statistical maps, Mel scripts have been used in Maya to take input from the user and change the shape of models accordingly to represent data. These maps are interactive and navigable and are designed to be easily accessible on the Web. URI: http://handle.tamu.edu/1969.1/1571 Files in this item: 1
etd-tamu-2004C-VIZA-Naz.pdf (3.134Mb) -
Thomas, Ryan Douglas (Texas A&M University, August 2003)[more][less]
Abstract: In the northern Gulf of Mexico, seafloor hydrocarbon fluid and gas seepage is an ubiquitous process on the continental margin. Although seafloor seepage and seep-related features (mud volcanoes, carbonate formation) have been studied for many years, little is known about their mechanisms of formation and the relationship of sub-surface structure to current seep activity. In this study, we examined three seafloor seeps in the Garden Banks and Mississippi Canyon areas using exploration and reprocessed 3D multi-channel seismic (MCS) data augmented with side-scan sonar (Garden Banks site) to characterize hydrocarbon seep activity and develop an understanding of the processes that led to their formation. Side-scan sonar data provided high resolution coverage of the seafloor while the exploration seismic data were used to image near and deep sub-surface features. Additionally, the 3D amplitude extraction maps were useful in delineating amplitude anomalies often associated with seep related activity. The reprocessed 3D seismic data were used to map in greater detail near seafloor features and amplitude anomalies. Using remote sensing geophysical data, we were effectively able to map sub-surface features such as salt topography, seep-related faults and geophysical indicators of hydrocarbons and correlate them with seafloor amplitude anomalies and fault traces in order to characterize seep activity level. The southern mud volcano in the Garden Banks site is characterized as an established high flux seep vent owing to signs of active seepage and sediment flows as well as the build-up of hard grounds. The northern mud volcano in the area, with greater hard ground build-up and fewer signs of active seepage represents an established low flux seep vent. In the Mississippi Canyon area, the data suggest that the seep mound can be characterized as a mature high flux vent due to the extensive build-up of hard ground, evidence of gas hydrates and signs of active seepage and sediment flows. The mechanisms of formation are similar between the two study sites. Upwelling salt appears to have fractured the sub-surface leading to the formation of fault induced depressions. Mapping of geophysical indicators of hydrocarbons implies that hydrocarbon migration is occurring along bedding planes to the fault systems underlying the depressions. Here they appear to migrate vertically to the seafloor creating the topographic features and seafloor amplitude anomalies that characterize the seeps URI: http://handle.tamu.edu/1969.1/1176 Files in this item: 1
etd-tamu-2003B-2003070408-Thom-1.pdf (4.113Mb) -
Arzuman, Sadun (Texas A&M University, December 2002)[more][less]
Abstract: In this study, the structure, depositional system, and the seismic stratigraphy of the VLE 196 area, Block V in Lamar Field were interpreted using 3-D seismic data and well logs to characterize structural and depositional settings of the Guasare-Misoa interval. To demonstrate structural settings of the study area 3-D seismic data were interpreted. Three main seismic reflectors, which are the Late Eocene unconformity, Guasare, and La Luna formations, were picked. The most dominant structure in the area is the VLE 400 Fault which was interpreted as a left-lateral strike-slip reverse fault due to its behaviors as a reverse fault in cross sections and as a strike-slip fault in strike sections. The VLE 400 Fault subdivides the VLE 196 area into two main structural blocks, a downthrown block in the western part and the upthrown block in the eastern part of the field where the hydrocarbons were trapped. Several en echelon normal and reverse faults were located along the both sides of the area. The main importance of these faults are that they fractured the La Luna source rock and created migration pathways through the reservoir layers of the Misoa Formation. To interpret depositional system of the Guasare-Misoa interval, tops of the C4 and C5 intervals and associated C4 layers were picked based on well logs and lithofacies maps were prepared. The results of this part of the study show that the sandstones of the Misoa Formation are delta front and fluvial/distributary channel facies of delta system. The net sand thickness map of the C4 interval also exhibits southeast northwest contour patterns reflecting depositional axes in the area. Shaly units of the C4 interval interpreted as potential seals and are of variable thickness and extend. Seismic stratigraphic interpretation of the area shows that the four main seismic facies are dominant which mainly represent the recent sediments, "C" sands of the Misoa Formation, underlying Colon and Mito Juan shales, and basement respectively. Some distributary eroded channel fill structures were also observed within the Misoa Formation, but they were not continuous through the area because of the intensive faulting. URI: http://handle.tamu.edu/1969.1/557 Files in this item: 1
etd-08192002-204126-1.pdf (9.269Mb) -
Howard, Jeff W. (May 10, 2005)[more][less]
Abstract: 4-H activities offer young people many exciting opportunities for personal development. These activities often are a part of their projects. This publication outlines activity options. Description: 2 pp. URI: http://handle.tamu.edu/1969.1/87241 Files in this item: 1
pdf_1970.pdf (532.7Kb) -
Howard, Jeff W. (May 10, 2005)[more][less]
Abstract: 4-H activities offer young people many exciting opportunities for personal development. These activities often are a part of their projects. This publication outlines activity options. Description: 2 pp. URI: http://handle.tamu.edu/1969.1/87323 Files in this item: 1
pdf_2147.pdf (576.7Kb) -
Howard, Jeff W. (May 10, 2005)[more][less]
Abstract: The strength and success of a local 4-H club are directly related to the amount of support provided by local people. To strengthen community support and participation, follow these guidelines when planning activities. Description: 2 pp. URI: http://handle.tamu.edu/1969.1/87243 Files in this item: 1
pdf_1972.pdf (514.7Kb) -
Howard, Jeff W. (May 10, 2005)[more][less]
Abstract: The strength and success of a local 4-H club are directly related to the amount of support provided by local people. To strengthen community support and participation, follow these guidelines when planning activities. Description: 2 pp. URI: http://handle.tamu.edu/1969.1/87325 Files in this item: 1
pdf_2149.pdf (557.1Kb)
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