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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.
81

A comparative analysis of supply chain management practices by Boeing and Airbus : long-term strategic implications

Horng, Tzu-Ching January 2007 (has links)
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, February 2007. / Includes bibliographical references (p. 127-131). / The goal of this research is to develop an improved understanding of supply chain management strategies and practices being pursued by Boeing and Airbus in the 787 Dreamliner and the A380 Navigator programs, respectively, and to identify their long-term strategic implications for supply chain management in the future. The research takes as its point of departure a review and synthesis of supply chain management principles and practices, with particular emphasis on lean supply chain management concepts. Guided by this review, the research focuses on the common set of suppliers supporting both programs and employs a questionnaire survey, followed by telephone interviews with representatives of selected suppliers. The research also makes extensive use of the open source information on both companies, on both programs and on the common suppliers. / (cont.) A major finding is that Boeing's new supply chain model in the 787 program represents a significant break with past practices in the aerospace industry, allowing major partnering suppliers an unprecedented role in terms of design, development, production and after-market support, where they are integrated early in the concept development stage and are incentivized to collaborate with Boeing, as well as among themselves, as risk-sharing partners with deep responsibility for system integration, involving detailed interface control at the system and subsystem levels. Airbus, as well, is found to rely heavily on its major suppliers in connection with the A380 program, but acting as the primary system integrator in the more traditional mode and exercising much greater control of all design interfaces. Also, both Boeing and Airbus have been outsourcing more and more activities to suppliers located in non-traditional regions, such as Eastern Europe and the Asia-Pacific region. Finally, aerospace manufacturers, in general, are aggressively adopting information technologies (e.g., EDI, PLM, 3-D Digital Model, RFID) to facilitate greater data sharing and communications with their partners and lower-tier suppliers dispersed in many geographical regions, as part of a broader trend involving more collaborative supplier relationships reaching down to the subtier level. / by Tzu-Ching Horng. / S.M.
82

Water supply enhancement in Cyprus through evaporation reduction

Cox, Chad W. (Chad Wayne), 1970- January 1999 (has links)
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.
83

The strategic potential of design-build in the information age

Collins, James M. (James Michael), 1966- January 2000 (has links)
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.
84

Strategic indicators for characterization of water system infrastructure and management

Garvin, Michael J. (Michael Joseph) January 2001 (has links)
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.
85

Basin-scale modeling of nutrient impacts in the Eel River Watershed, Plymouth, Massachusetts

Herman, Kurt D. (Kurt David), 1974- January 2002 (has links)
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.
86

Animation for computer integrated construction

Fukuchi, Yoshihiko January 1994 (has links)
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.
87

Patterns of shallow clouds and rainfall over the Amazon : climatic impacts of deforestation

Chagnon, Frédéric J. F. (Frédéric Jacques F.), 1975- January 2005 (has links)
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.
88

Drivers' evaluation of advanced traveller information systems for inter-city expressways in Japan

Murashige, Yoshiyasu January 1995 (has links)
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.
89

Water resources of west Cape Cod : an investigation of water supply and demand planning

Manning, Jill Anna January 1997 (has links)
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.
90

Oil reservoir characterization using ensemble data assimilation

Jafarpour, Behnam January 2008 (has links)
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.

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