Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1999. / Includes bibliographical references (leaves 114-116). / by Chad W. Cox. / M.Eng.

Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2000. / Includes bibliographical references (leaf 55). / by James M. Collins. / M.Eng.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2001. / Includes bibliographical references (p. 196-203). / Shifts in the US water industry are characteristic of the flux found across all infrastructure sectors. Economic, environmental, market, regulatory and systemic forces are pushing the industry toward a different future where challenges of significant capital formation, competitiveness, efficiency and resource allocation will be prevalent. Amidst these drivers, longstanding assumptions about water provision and management are under scrutiny. The path forward remains unsettled as industry players debate the role of the federal government in financing pending capital challenges. The two sides of the debate describe divergent paths, and the one taken will define the industry's near-term structure. One hand indicates a pending crisis that necessitates substantial federal assistance while the other suggests staying the course towards self-sufficiency. / (cont.) Missing from these discussions is objective evidence concerning the state of the industry. To supply the missing component, this thesis develops and applies a rational methodology to characterize a national cross section of large water systems. The methodology provides a basis for (a) understanding the state of systems within the national portfolio and (b) guiding strategic assessment and policy development. A set of common, core indicators are deployed that rely upon widely available operating and financial data and make use of thresholds that serve as estimates of industry-wide averages or standards. Once applied, the indicators provide grounds for describing an enterprise's structure and core functions as well as assessing both capital needs and opportunities. The evidence indicates that large systems are adequately positioned to handle near-term capital challenges, so an expanded federal role is unnecessary. In addition, alternatives that might improve national water provision remain largely untested, so policies and strategies that support exploration of these approaches are recommended. The work presented is a key step toward normalizing an industry. / by Michael J. Garvin. / Ph.D.

Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2002. / Includes bibliographical references (p. 74-77). / by Jurt D. Herman. / M.Eng.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1994. / Includes bibliographical references (leaves 148-163). / by Yoshihiko Fukuchi. / M.S.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2005. / Includes bibliographical references. / (cont.) and, to a lesser extent, cold cloud patterns over the Amazon. Through complex interactions, the results reported in this thesis may have important implications for the local ecosystem dynamics of the Amazon, for the geomorphology of the Amazon river basin, for the flow regimes of the Amazon river, and for global climate. / The climatic impact of the current state of deforestation in the Amazon basin is examined in this thesis. Past modeling studies have shown that complete deforestation of the Amazon basin could result in dramatic decreases in regional rainfall and evaporation leading to desertification (e. g., Salati and Vose [1984], Shukla et al. [1990]). Yet, although 15% of the 4,000,000 km² Brazilian Amazon has already been deforested [INPE, 2003], current deforestation patterns in the Amazon basin are not uniform, nor do their extents surpass tens of kilometers. Numerical simulations indicate that idealized heterogeneities of land-surface properties could lead to organized mesoscale circulations that enhance convection (e. g., Anthes [1984], Chen and Avissar [1994a], Avissar and Liu [1996], Wang et al. [1998]); similar results were found in case-study simulations of actual Amazon deforestation (e. g., Wang et al. [2000], Roy and Avissar [2002]). Qualitative observations of enhanced shallow cloud cover over cleared areas have provided preliminary indications of episodic land-cover-driven mesoscale circulations in the Amazon basin (e. g., Cutrim et al. [1995], Durieux et al. [2003], Negri et al. [2004]). Based on these studies, the effects of the "fishbone" patterns of deforestation on shallow vection were thought to occur only episodically during few precious weeks toward the end of the dry season, and were largely accepted as being climatically insignificant. However, through the use of satellite data from the Geostationary Operational Environmental Satellite (GOES) and the Tropical Rainfall Measuring Mission (TRMM), this thesis quantitatively demonstrate that the complex pattern of deforestation in the Amazon has resulted in a climatic shift in shallow cloud, rainfall / by Frédéric J. F. Chagnon. / Ph.D.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1995. / Includes bibliographical references (leaves 165-172). / by Yoshiyasu Murashige. / M.S.

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1997. / Includes bibliographical references (leaves 92-95). / by Jill Anna Manning. / M.Eng.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2008. / Pages 211-212 blank. / Includes bibliographical references. / Increasing world energy demand combined with decreasing discoveries of new and accessible hydrocarbon reserves are necessitating optimal recovery from the world's current hydrocarbon resources. Advances in drilling and monitoring technologies have introduced intelligent oilfields that provide real-time measurements of reservoir conditions. These measurements can be used for more frequent reservoir model calibration and characterization that can lead to improved oil recovery though model-based closed-loop control and management. This thesis proposes an efficient method for probabilistic characterization of reservoir states and properties. The proposed algorithm uses an ensemble data assimilation approach to provide stochastic characterization of reservoir attributes by conditioning individual prior ensemble members on dynamic production observations at wells. The conditioning is based on the second-order Kalman filter analysis and is performed recursively, which is suitable for real-time control applications. The prior sample mean and covariance are derived from nonlinear dynamic propagation of an initial ensemble of reservoir properties. Realistic generation of these initial reservoir properties is shown to be critical for successful performance of the filter. When properly designed and implemented, recursive ensemble filtering is concluded to be a practical and attractive alternative to classical iterative history matching algorithms. A reduced representation of reservoir's states and parameters using discrete cosine transform is presented to improve the estimation problem and geological consistency of the results. The discrete cosine transform allows for efficient, flexible, and robust parameterization of reservoir properties and can be used to eliminate redundancy in reservoir description while preserving important geological features. / This improves under-constrained inverse problems such as reservoir history matching in which the number of unknowns significantly exceeds available data. The proposed parameterization approach is general and can be applied with any inversion algorithm. The suitability of the proposed estimation framework for hydrocarbon reservoir characterization is demonstrated through several water flooding examples using synthetic reservoir models. / by Behnam Jafarpour. / Ph.D.

Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2003. / Includes bibliographical references (leaves 68-69). / The proposed construction of a new high-speed rail link between Amsterdam and Brussels involves construction of embankments overlying soft clay and peat deposits with very stringent requirements on the time frame of construction and allowable settlements. A field program of instrumented test embankments, referred to as No-Recess, has compared the performance of five schemes for stabilizing the soft ground behavior. This thesis summarizes the No-Recess project and compares the measured performance for two instrumented using finite element analysis. The results confirm the benefits of geotextile encased sand columns as a practical technique for stiffening underlying soft soils, accelerating consolidation and reducing settlements. / by Isabella Santini Batista. / M.Eng.