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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.
61

A Charge-Balancing Incremental Analog to Digital Converter for Instrumental Applications

Zrilić, D., Skendzić, D., Pajavić, S., Ghorishi, R., Fu, F., Kandus, G. 10 1900 (has links)
International Telemetering Conference Proceedings / October 17-20, 1988 / Riviera Hotel, Las Vegas, Nevada / A switched-capacitor technique for realization of one bit serial A/D converter is presented. A conversion accuracy that is higher than 15 bits can be expected from its integrated realization. Results of simulation are presented. It is shown that arithmetic operations on bit serial signals are possible. Using arithmetic operations on delta-modulated signals, it is possible to build inexpensive options necessary in instrumentation.
62

A comparison of full swing and partial swing SRAM read topologies

Truong, Bao Gia 2009 August 1900 (has links)
This paper outlines design considerations and implementation details of full swing and of partial swing SRAM arrays. Comparisons between the two methods based on performance, power, and noise rejection are then presented. Finally, a decision matrix will be provided that selects the better topology based on varying design constraints. / text
63

Superconducting Transformer Design and Construction

Chew, En Phin January 2010 (has links)
This thesis first outlines the testing undertaken on a partial core superconducting transformer under open circuit, short circuit, full load and endurance test conditions. During the endurance test, a failure occurred after 1 minute and 35 seconds. During the failure, voltage dipping and rapid liquid nitrogen boil off was observed. This prompted a failure investigation which concluded that the lack of cooling in the windings was the most probable cause to the failure. Full core transformer and superconductor theories are then introduced. A copper winding transformer model, based on a Steinmetz equivalent circuit and a reverse design method, is described. A superconductor loss model which outlines the different types of losses experienced under AC conditions is used to determine the resistance of the windings in the Steinmetz equivalent circuit. This resistance changes with the magnitude of current and the strength of the magnetic field that is present in the gaps between each layer of the windings. An alternative leakage flux model is then presented, where the flux is modelled based on the combination of the reluctance of the core and the air surrounding the windings. Based on these theories, an iterative algorithm to calculate the resistance of the superconductor is developed. A new design of a 15kVA single phase full core superconducting transformer, operating in liquid nitrogen, is presented. The issues with building the superconducting transformer are outlined. First, a copper mockup of the superconducting transformer was designed where the mockup would have the same tape and winding dimensions as the superconducting transformer, which means the same core can be used for two different sets of windings. This led to designing a core that could be easily taken apart as well as reassembled. Construction of the core, the copper windings and the superconductor windings ensued. The process of cutting the core laminations, insulating the copper and superconductor tapes, and making the steel fasteners and terminations are described. The copper mockup and superconducting transformers was then tested under open circuit, short circuit, different load and endurance conditions at both liquid nitrogen and room temperatures. These test results were then compared with the those from two models. The comparison showed a significant inaccuracy in the reactances in the models. This introduced a correction factor into the superconductor model which ii made it more accurate. However, further work is required to explain and quantify the correction factors for the copper transformer model under different load conditions.
64

Nutritional value of soya beans for broiler chicks

Clarke, Emily Jane January 2001 (has links)
No description available.
65

Quality Assessment for HEVC Encoded Videos: Study of Transmission and Encoding Errors

Ansari, Yousuf Hameed, Siddiqui, Sohaib Ahmed January 2016 (has links)
There is a demand for video quality measurements in modern video applications specifically in wireless and mobile communication. In real time video streaming it is experienced that the quality of video becomes low due to different factors such as encoder and transmission errors. HEVC/H.265 is considered as one of the promising codecs for compression of ultra-high definition videos. In this research, full reference based video quality assessment is performed. The raw format reference videos have been taken from Texas database to make test videos data set. The videos are encoded using HM9 reference software in HEVC format. Encoding errors has been set during the encoding process by adjusting the QP values. To introduce packet loss in the video, the real-time environment has been created. Videos are sent from one system to another system over UDP protocol in NETCAT software. Packet loss is induced with different packet loss ratios into the video using NETEM software. After the compilation of video data set, to assess the video quality two kind of analysis has been performed on them. Subjective analysis has been carried on different human subjects. Objective analysis has been achieved by applying five quality matrices PSNR, SSIM, UIQI, VFI and VSNR. The comparison is conducted on the objective measurement scores with the subjective and in the end results deduce from classical correlation methods.
66

Full Costing in the Petroleum Industry and its Implications for Accounting Principles and Practices

Klingstedt, John P. 05 1900 (has links)
The study of the full cost method of accounting for finding costs in the petroleum industry is significant because it offers a unique opportunity to examine and emerging accounting practice and will indicate some of the reasons for a shift in the reporting practices of a portion of the industry.
67

Thermal Driven Water Treatment Systems for Full Separation of Solute-Water

Mehta, Sahib, Mehta, Sahib January 2016 (has links)
This work encompasses the study of a novel thermal driven desalination system to accomplish full separation of water and solute. This process advantageous over other process because it involves zero recirculation and zero liquid discharge, thus having minimum environmental impact. Since this system provides full separation, salts and other valuable products can be obtained in addition to pure water. This system can operate at high energy efficiencies using medium temperature heat source like industrial reject or solar cells. This plant consists of two technologies, the full separation and multi effect distillation which when integrated together 8ive us water and salt separately. Three different configuration of the FS-MED system have been presented, naming concurrent feed, variable feed, and counter current feed. They vary depending on their flow and feed distribution. Numerical procedure has been developed to solve the energy and mass balance equation for steady state condition has been presented.
68

Eternal Return

Kopacz, Timothy N. January 2013 (has links)
Thesis advisor: John Houchin / The objective of this project was to attempt not only to adapt the novel "The Master and Margarita" by Mikhail Bulgakov to the stage, but rather to translate it in both time and place to the stage. It has been more than 60 years since the novel was written, and as such the concerns of the characters have changed both in time and locale. Not only are their objectives adjusted, but the novel is ultimately that: a novel. Being a theatrical adaptation, the play must acknowledge its own existence as such and take issue with its form as much as "The Master and Margarita" does its own. The play is, ultimately, a failed one in my opinion. The greatest downfall thereof being the fact that theatre, drama, is centered around a single thing: conflict. The devil can be in conflict with no one but the divine, and as such any time he is on stage there is simply something missing. The failure is, to a certain extent, befitting of the piece for what it takes to heart as its issues. Enjoy. / Thesis (BA) — Boston College, 2013. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: College Honors Program. / Discipline: Theater.
69

Development of a Computer Program for the Verification and Validation of Numerical Simulations in Roadside Safety

Mongiardini, Mario 06 May 2010 (has links)
Roadside safety hardware has traditionally been approved on the basis of full-scale crash tests. In recent years, nonlinear dynamic Finite Element (FE) programs like LS-DYNA, PAM-Crash or ABAQUS Explicit have been widely used in evaluating new or improved design of roadside hardware. Although a powerful tool, numerical models must be properly verified and validated in order to provide reliable results. Typically, the verification and validation (V&V) process involves a visual comparison of two curves and is based on a purely subjective judgment. This research investigated the use of comparison metrics, which are mathematical measures that quantify the level of agreement between two curves, for comparing simulation and experimental outcomes in an objective manner. A computer program was developed in Matlab® to automatically evaluate most of the comparison metrics available in literature. The software can be used to preprocess and compare either single or multiple channels, guiding the user through friendly graphical interfaces. Acceptance criteria suitable to represent the typical scatter of experimental tests in roadside safety were determined by comparing ten essentially identical full-scale vehicle crash tests. The robustness and reliability of the implemented method were tested by comparing the qualitative score of the computed metrics for a set of velocity waveforms with the corresponding subjective judgment of experts. Moreover, the implemented method was applied to two real validation cases involving a numerical model in roadside safety and a model in biomechanics respectively. Eventually, the program showed to be an effective tool to be used for assessing the similarities and differences between two curves and, hence, for assisting engineers and analysts in performing verification and validation activities objectively.
70

Smoke Movement Analysis (Smoke Transport Within a Corridor)

Cummings, W. Mark 18 November 2004 (has links)
"A series of full-scale fire tests were performed, using a fire compartment and an adjoining long (30+ m) corridor, as part of an effort to quantify the dynamics associated with smoke transport within a corridor. The tests were performed at the U.S. Coast Guard Research and Development Center’s Fire and Safety Test Detachment in Mobile, Alabama on board the Test Vessel Mayo Lykes. The resulting empirical data was analyzed in an effort to develop a method that could be used to estimate the movement of smoke within a corridor. The objective is to potentially incorporate this method into a smoke movement analysis “tool” that could, in turn, be used in conjunction with a fire safety analysis methodology previously developed by the U.S. Coast Guard; the Ship fire Safety Engineering Methodology (SFSEM). The goal is to develop a smoke movement analysis “module” that can be utilized in conjunction with the SFSEM when conducting an overall fire safety analysis of a ship. Of particular interest is the speed at which the smoke propagates along the length of the corridor. The focus of a smoke movement module would be life safety. A conservative assumption is made that if smoke is present in sufficient quantities to fill a corridor, then the corridor is to be considered untenable and not available as a means of egress. No attempt is made to address toxicity or density issues associated with smoke. This analysis developed correlations for the corridor smoke velocity, both as a function of the heat release rate of the associated fire and the upper layer temperatures within the fire compartment. Problems associated with the data collection and the narrow range of fire sizes used had a detrimental impact on the confidence level in the correlation based on heat release rate. The data do appear to confirm the results of previous efforts that indicated a weak relationship between the heat release rate and smoke velocity, on the order of the one-third to one-fourth power. The temperature data tended to be less problematic. This correlation shows promise for potential use with both the SFSEM and other existing computer models/routines. However, unlike previous studies of this relationship, the results of these data suggest that the velocity-temperature relationship is linear and not a square-root function. The test data were compared to predictive results using the CORRIDOR routine within FPETOOL. In general, the CORRIDOR results provided a reasonable good correlation to the tests data. Both the wave depth and temperature loss within the wave, as a function of distance, were consistently over-predicted. The velocity results were mixed, but were generally within 20 percent of the test data. The results of this study show promise, with respect to developing a correlation that can be used a method for predicting smoke movement in a corridor. However, due to the questionable nature of some of the data estimates, coupled with both a lack of sufficient number of tests and a limited range of fire sizes used, additional test data will be required to further validate the accuracy and refine the correlation(s) suggested by this work."

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