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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

Plane-Based Calibration for Multibeam Echo Sounder System Mounting Parameters

Her, Zhi-Wei 22 August 2003 (has links)
Multibeam sonar systems are much more efficient than the convectional single-beam echo sounders for seafloor-mapping in hydrographic surveying. On the other hand, the operation of multibeam sonar systems needs to integrate more auxiliary sensor units. Because the world coordinates of each footprint is calculated based on the geometry of the sonar head relative to the GPS of the ship. Therefore, the resulting survey quality highly depends on the accuracy of the estimated mounting configuration of the sonar head, and other sensor units. Basically, the configuration parameters include the three Euler's angles, three linear translations and the asynchronous latency of signals between the transducer and other sensors. These parameters can not be measured directly. They can only be estimated from the post-process of the bathymetry data called patch test. Generally, the patch test requires the survey ship to follow several designated paths which are parallel, reciprocal or perpendicular to each other. Furthermore, the choice of seabed slope is also an important factor for the quality of the result. The contour plots of the seabed for the different paths are used to estimate the mounting configuration of the sonar head. In this work, we propose best-fitting a small flat patch to represent the seabed right beneath a segment of the path. A pair of patches from the two adjacent segments of reciprocal or perpendicular paths are selected for comparison. The difference between the two patches gives us an idea how the mounting parameters, i.e. the rolling, pitching and yawing angles, might be. If the parameters are accurately estimated, the two patches should be co-plane. We design several semi-positive definite functions and feed back control algorithms to steer the mounting angles to search for the solutions. One more advantage of this approach is that the variation of each mounting angles as the survey undergoes can be monitored. We test this idea with simulated seabed data, and field data as well. The result is within 1\% difference compared with respect to the angles calibrated by commercial software, such as Hypack.
82

Factors for success in community-based corrections : a regression analysis /

Cox, Dawn Ann. January 2009 (has links)
Thesis (M.S.)--Youngstown State University, 2009. / Includes bibliographical references (leaf 59). Also available via the World Wide Web in PDF format.
83

Investigation into the effectiveness of an inquiry-based curriculum in an introductory biology laboratory /

Harris, Molly Ann, January 2009 (has links)
Thesis (M.S.) in Teaching--University of Maine, 2009. / Includes vita. Includes bibliographical references (leaves 131-135).
84

Selected Bachelor of Science in nursing programs variables impacting graduate scores on the National Council Licensure Examination for Registered Nurses

Borek, Lois B. January 2006 (has links)
Thesis (Ed.D.)--Liberty University School of Education, 2006. / Includes bibliographical references.
85

Has it happened in Mpumalanga? an evaluation of the implementation of Curriculum 2005 /

Mtetwa, Albert Charles. January 2003 (has links)
Thesis (M.A. (Research Psychology))--University of Pretoria, 2003. / Includes bibliographical references.
86

A probabilistic similarity framework for content-based image retrieval /

Aksoy, Selim. January 2001 (has links)
Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 245-272).
87

Parent perceptions, interests and involvement in a campus childcare center

Wolf, Marcia A. January 2001 (has links) (PDF)
Thesis--PlanB (M.S.)--University of Wisconsin--Stout, 2001. / Includes bibliographical references.
88

Testing in the schools individualized intelligence tests and curriculum based measurements /

Emery, Kristine Louise. January 2003 (has links) (PDF)
Thesis--PlanB (M.S.)--University of Wisconsin--Stout, 2003. / Includes bibliographical references.
89

Calibration of and attitude error estimation for a spaceborne scatterometer using measurements over land /

Wilson, Clarence J., January 1998 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Electrical and Computer Engineering, 1998. / Includes bibliographical references (leaves 63-64).
90

Online professional development a study of first year online teachers /

Boyarko, Maria A. January 2009 (has links)
Thesis (Ph.D.)--Kent State University, 2009. / Title from PDF t.p. (viewed Jan. 22, 2010). Advisor: Steven L. Turner. Keywords: Online professional development. Includes bibliographical references (p. 191-197).

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