• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 880
  • 22
  • 6
  • Tagged with
  • 1137
  • 1137
  • 175
  • 169
  • 145
  • 69
  • 52
  • 45
  • 44
  • 44
  • 42
  • 41
  • 41
  • 41
  • 40
  • 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.
231

Variable ballast system design for an unmanned submersible

Carroll, Alf L January 1983 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1983. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING / Includes bibliographical references. / by Alf L. Carroll, III. / M.S.
232

Government intervention in the shipping industry

Kokkalas, Georgios, 1974- January 2002 (has links)
Thesis (S.M. in Ocean Systems Management)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 2002. / Includes bibliographical references (leaves 125-127). / by Georgios Kokkalas. / S.M.in Ocean Systems Management
233

Econometric modeling of ocean freight rates : the case of tankers

Ayvatoglu, Dimitris, 1976- January 2001 (has links)
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 2001. / Includes bibliographical references (p. 99-100). / by Dimitris Ayvatoglu. / S.M.
234

Vessel valuation : an options approach

Largiadèr, Caspar Andri, 1965- January 1999 (has links)
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1999. / Includes bibliographical references (p. 74-75). / In the field of capital budgeting traditionally the widely accepted net-present-value (NPV) technique is used to capture a project's value. However, this approach fails to quantify managerial and operational flexibility and strategic interactions. The underlying analysis deals with the subject of resource allocation or capital budgeting under uncertainty, particularly with the valuation of managerial and operating flexibility as real options. Similar to options on financial assets, real options involve decisions or rights, with no obligation, to acquire or exchange an asset or project for a pre-specified price. Within the shipping industry the application of real options on operating vessels as strategic decision tools has so far been more or less neglected, since only few players are familiar with the option theory. A charterer operating a vessel may have an agreement with the owner to acquire the ship at some future date, giving him the option, without obligation, to do so. This flexibility to undertake a vessel acquisition provides the charterer with a certain value, depending on the movements of the market. This paper initially introduces the general option pricing theory applied to financial securities. Furthermore, an alternative way of modeling the stochastic nature of time charter. equivalent spot rates for the bulk freight market is presented. It is proposed to abandon the Geometric Brownian motion and, instead, to apply a mean reverting process, such as the OmsteinUhlenbeck process, to replicate the freight rates. Based on these findings, closed form option valuation tools are applied to a Panamax vessel type for one specific route, capturing the mean reverting character of the ship's cash flows. The results of the option valuation are discussed considering their practicability. Finally, recommendations for future research are given. / by Caspar Andri Largiadèr. / S.M.
235

Design procedures for submarine-deployable bistatic sonar systems

Dondey, Philippe Porter January 1984 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1984. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / by Philippe Porter Dondey. / M.S.
236

Scattering from sub-critically insonified buried elastic shells

Lucifredi, Irena January 2005 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, February 2005. / Includes bibliographical references (p. 211-217). / Buried mines have been so far generally considered undetectable by conventional high frequency sonars mostly due to the low levels of energy penetrating into the sediment at high frequencies. Furthermore, in a shallow water environment a high frequency high grazing angle mine-hunting sonar approach is vastly limited by the coverage rate, making the detection and classification of buried objects using subcritical grazing incidence an attractive alternative. In mine countermeasurements (MCM) applications resonance of man-made elastic targets is a pivotal concept that distinguishes them from rocks or other clutter that may have a similar mine-like shape. Nevertheless, burial of an elastic target in the seabed results in a variety of modifications to the scattered response caused by different physical mechanisms, geometric constrains, and intrinsic properties of the sediment. The goal of this thesis was to identify, analyze and explain the fundamental effects of the outer sediment and the proximity of the seabed interface on the scattering of sound from elastic shells insonified using low frequencies at subcritical incident angles. / (cont.) The approach to scattering from buried elastic shells consisted of the development and the evaluation of ways of computing the scattered field, and the interpretation of the physical events taking place. A class of numerical models called virtual source models was developed and used, which take into account and are able to represent all of the, to our problem, significant physical mechanisms comprising the scattering effect observable in an at-sea experiment. Time-frequency and array processing methods for extracting properties of buried target signatures that can be used to classify the targets based on their re-radiated returns, have been developed. A theoretical time-of-arrival tool was created and implemented to obtain the expected times of arrival of specular and elastic responses of buried elastic targets and therefore identify the target elastic waveforms. In addition, a novel focused beamforming approach that was formulated and implemented, was used to determine the elevation angles at which specular and elastic returns emerge from the seabed into the water-column. / (cont.) Through the analysis of GOATS98 experimental data, validation of target scattering models, and hypothesis validation, the frequency and the amplitude content as well as the times of arrival of target elastic response have been examined. For the first time in literature, a difference in the frequency content of clockwise and counter-clockwise Lamb wave components under subcritical insonification was observed and explained. Using focused beamforming, specular and elastic arrivals were identified, demonstrating the different elevation angles at which they emerge from the seabed into the water-column. As a result, a hypothesis about the physics of propagation of elastic waves under evanescent insonification was validated, thus confirming that the nature of the physical processes taking place can not be described using the traditional wave-tracing arguments, rendering them inadequate under these circumstances. Furthermore, related to the detection of fully buried targets, which was so far considered a challenging problem, the shown specifics of the structural waves radiation and propagation process provide a distinct way of determining the presence of these otherwise hardly detectable targets. / by Irena Lucifredi. / Ph.D.
237

A comparison of fatigue crack propagation in Inconel 625 and 3.25 Ni steel.

Long, Thomas Albert January 1972 (has links)
Massachusetts Institute of Technology. Dept. of Ocean Engineering. Thesis. 1972. Ocean E. / MICROFICHE COPY ALSO AVAILABLE IN BARKER ENGINEERING LIBRARY. / Includes bibliographical references. / Ocean E.
238

Propulsive efficiency of a flexible hull underwater vehicle

Barrett, David Scott January 1996 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1996. / Includes bibliographical references (leaves 183-186). / by David Scott Barrett. / Ph.D.
239

Trace metal sources for the Atlantic inflow to the Mediterranean Sea

Geen, Alexander F. M. J. van January 1989 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1989. / Vita. / Includes bibliographical references. / by Alexander F.M.J. van Geen. / Ph.D.
240

The propagation of water waves over sediment pockets.

Lassiter, J. B January 1972 (has links)
Massachusetts Institute of Technology. Dept. of Ocean Engineering. Thesis. 1972. Ph.D. / MICROFICHE COPY ALSO AVAILABLE IN BARKER ENGINEERING LIBRARY. / Vita. / Bibliography: leaves 52-53. / Ph.D.

Page generated in 0.0913 seconds