Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1995. / Includes bibliographical references (leaves 95-99). / by Joshua Allen Joseph, Jr. / M.S.

Thesis (S.M.)--Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2013. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 127). / Both vibration-based structural health monitoring methodologies and seismic performance analysis rely on estimates of the base-line dynamic behavior of a structure. A common method for making this estimate is through measuring structural motions using sensors deployed in the structure of interest. This procedure was applied to the Green Building, a 20 story structure on the campus of the Massachusetts Institute of Technology. Using a network of 36 accelerometers installed in the structure by the United States Geological Survey, the response accelerations from ambient vibrations, seismic loading, and firework excitations were collected. Spectral analysis methods were applied to the collected data to identify the frequencies and general mode shapes of eight normal modes of the structure. These frequencies were 0.68 Hz, 2.45 Hz, and 8.10 Hz in the east-west direction; 0.75 Hz, 2.85 Hz, and 8.25 Hz in the north-south direction; and 1.45 Hz and 5.05 Hz in torsion. The building was found to have strong torsional responses, an asymmetry in the dynamic behavior of the eastern and western sides, and substantial base rocking motion, even under ambient excitations. Using the original design documents, the Green Building was numerically modeled with a lump-mass stick model and a mixed-element beam-shell finite element model. These models were validated and refined using the collected acceleration data. Initial simulations of seismic excitations demonstrated both models to have good agreement with measured values. The numerical models and structural characterization of the Green Building will be used to further develop vibration-based damage detection methodologies and to predict structural performance during strong seismic events. / by Peter Adam Trocha. / S.M.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1996. / Vita. / Includes bibliographical references (p. 216-221). / by Qihang Li. / Ph.D.

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2004. / Includes bibliographical references (leaves 81-83). / Slow sand filtration is a method of water treatment that has been used for hundreds of years. In the past two decades, there has been resurgence in interest in slow sand filtration, particularly as a low-cost, household-scale method of water treatment. During January 2004, the author traveled to the northwestern Dominican Republic to evaluate the performance of BioSand filters installed over the past two years. BioSand filter performance was evaluated based on flow rate, turbidity removal and total coliform removal in communities surrounding the cities of Mao, Puerto Plata and Dajabon. Filter owners were interviewed about general filter use, water storage methods, filter maintenance practices, and water use. Data analysis revealed that even though the majority of filters were removing large portions of both total coliform and E. coli contamination, no filters met the WHO water quality guideline of less than one CFU/100 ml. Analysis also revealed that at low turbidities, turbidity removal and total coliform removal are not correlated. Examination of flow rate and bacterial removal near Puerto Plata revealed that filters with fast flow rates and intermittent chlorination were observed to have the lowest total coliform removal rates. Analysis of storage data revealed that failure to use safe water storage containers leads to recontamination of filtered water. During Spring of 2004, a laboratory was conducted to examine longer-term thermotolerant coliform and turbidity removal. The study compared removal rates between two BioSand filters, one of which was paired with a geotextile prefilter used in the construction of the Peruvian Table Filter. The study revealed that thermotolerant coliform removal rates by the BioSand filter without / (cont.) the geotextile stabilized after an initial period of lower bacterial removal efficiency. Thermotolerant coliform removal in the BioSand filter with the geotextile prefilter dropped throughout the experiment, suggesting that pairing a BioSand filter with a prefilter is detrimental to filter performance. Combining the results of the survey analysis and data gathered in the Dominican Republic with the results of the laboratory analysis of Spring 2004 suggests that BioSand filter users in the Dominican Republic should continue to use their filters. If possible, BioSand filter use should be combined with post-filtration chlorination to kill the remaining bacteria. The BioSand filter is a valuable and effective household-scale water treatment method for the Dominican Republic. / by Kori S. Donison. / M.Eng.

Massachusetts Institute of Technology. Dept. of Civil Engineering. Thesis. 1966. M.S. / MICROFICHE COPY ALSO AVAILABLE IN BARKER ENGINEERING LIBRARY. / Bibliography: leaves 123-124. / M.S.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2000. / Includes bibliographical references (p. 205-208). / by Elton K.L. Lin. / S.M.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2004. / Includes bibliographical references (leaves 63-66). / Statistical analysis methods used for interrogating functional magnetic resonance imaging (fMRI) data are complex and continually evolving. There exist a scarcity of educational material for fMRI. Thus, an instructional based software application was developed for teaching the fundamentals of statistical analysis in fMRI. For wider accessibility, the application was designed with a client/server architecture. The Java client has a layered design for flexibility and a nice Graphical User Interface (GUI) for user interaction. The application client can be deployed to multiple platforms in heterogeneous and distributed network. The future possibility of adding real-time data processing capabilities in the server led us to choose CGI/Perl/C as server side technologies. The client and server communicates via a simple protocol through the Apache Web Server. The application provides students with opportunities for hands-on exploration of the key concepts using phantom data as well as sample human fMRI data. The simulation allows students to control relevant parameters and observe intermediate results for each step in the analysis stream (spatial smoothing, motion correction, statistical model parameter selection etc.). Eventually this software tool and the accompanying tutorial will be disseminated to researchers across the globe via Biomedical Informatics Research Network (BIRN) portal. / by Vijay Singh Choudhary. / S.M.

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2005. / Includes bibliographical references (leaves 117-120). / One of the main components necessary for providing safe drinking water for users who lack piped water in the home is the ability to safely store it in the home. Users in the Nyanza Province of Kenya frequently carry water from some distance or purchase vended water and traditionally store this water in their homes in clay pots. CARE/Kenya, a non-governmental organization working in conjunction with local women potters and the Centers for Disease Control and Prevention, modified these clay pots so that they fit the definition of designated safe storage water containers, which contain the following three characteristics: a narrow mouth, a lid, and a tap to prevent recontamination. Three pottery production sites were visited in order to document, analyze, and suggest improvements for the design of the modified clay pots, specifically with regards to the standardization of the size and shape of the pots, so as to allow simple and convenient standardized household chlorine dosing, and the tap design and attachment, because the current tap design is expensive and prone to leaking. / (cont.) The modified clay pots displayed little variability in pot dimensions, and the 20 liter modified clay pots from the Amilo location showed a less than or equal to 10% volume variability that is acceptable according to the Centers for Disease Control and Prevention household chlorine dosing procedure. A reference rope tool developed to help standardize the size of modified clay pots can be used to train new potters but is not necessary for experienced potters. The spring-operated plastic tap was found to be the most promising design to replace the current metal tap design. The material cost of the modified clay pots at the three sites was determined with some certainty to range from 202-370 KSH (US$2.70-US$4.90). However, labor costs, transportation costs, profit margins and the role of subsidies, if they exist, were unable to be accurately determined. Therefore, cost recovery of the modified clay pot is unclear at all three pottery sites due to insufficient data. / by Suzanne E. Young. / M.Eng.

Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1908. / by Herbert C. Elton, H. Wiley Griswold. / B.S.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1998. / Includes bibliographical references (leaf 89). / by Gerld D. King. / M.S.