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Adjustment theory: an introduction
Peter Teunissen · TU Delft Open · 2024
Adjustment theory can be regarded as the part of mathematical geodesy that deals with the optimal combination of redundant measurements together with the estimation of unknown parameters. It is essential for a geodesist, its meaning comparable to what mechanics means to a civil engineer or a mechanical engineer. Historically, the first methods of combining redundant measurements originate from the study of three problems in geodesy and astronomy, namely to determine the size and shape of the Earth, to explain the long-term inequality in the motions of Jupiter and Saturn, and to find a mathematical representation of the motions of the Moon. Nowadays, the methods of adjustment are used for a much greater variety of geodetic applications, ranging from, for instance, surveying and navigation to remote sensing and global positioning. The two main reasons for performing redundant measurements are the wish to increase the accuracy of the results computed and the requirement to be able to check for errors. Due to the intrinsic uncertainty in measurements, measurement redundancy generally leads to an inconsistent system of equations. Without additional criteria, such a system of equations is not uniquely solvable. In this introductory course on adjustment theory, methods are developed and presented for solving inconsistent systems of equations. The leading principle is that of least-squares adjustment together with its statistical properties. The inconsistent systems of equations can come in many different guises. They could be given in parametric form, in implicit form, or as a combination of these two forms. In each case the same principle of least-squares applies. The algorithmic realizations of the solution will differ however. Depending on the application at hand, one could also wish to choose between obtaining the solution in one single step or in a step-wise manner. This leads to the need of formulating the system of equations in partitioned form. Different partitions
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Aerodynamics and Aircraft Performance
James Marchman III · Virginia Tech Libraries · 2004
Aerodynamics and Aircraft Performance, 3rd edition is a college undergraduate-level introduction to aircraft aerodynamics and performance. This text is designed for a course in Aircraft Performance that is taught before the students have had any course in fluid mechanics, fluid dynamics, or aerodynamics. The text is meant to provide the essential information from these types of courses that is needed for teaching basic subsonic aircraft performance, and it is assumed that the students will learn the full story of aerodynamics in other, later courses. The text assumes that the students will have had a university level Physics sequence in which they will have been introduced to the most fundamental concepts of statics, dynamics, fluid mechanics, and basic conservation laws that are needed to understand the coverage that follows. It is also assumed that students will have completed first year university level calculus sequence plus a course in multi-variable calculus. Separate courses in engineering statics and dynamics are helpful but not necessary. Any student who takes a course using this text after completing courses in aerodynamics or fluid dynamics should find the chapters of this book covering those subjects an interesting review of the material. The 236-page text was created specifically for use by undergraduate students in Aerospace Engineering and was based on Professor Marchman’s many years of experience teaching related subject matter as well as his numerous wind tunnel research projects related to aircraft aerodynamics and his personal experience as the owner and pilot of a general aviation airplane. It has been used at Virginia Tech and other universities. Instructors reviewing, adopting, or adapting parts or the whole of the text are requested to register their interest at: https://bit.ly/aerodynamics_interest.
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Stability of Ships and Other Bodies
Genick Bar-Meir · Potto Project · 2021
This book, Stability of Ships and Other Bodies, describes the fundamentals when and why floating bodies are stable. In addition, it describes steps that transforms un–stable bodies to stable. This book is designed to replace all the other books and inseminate that recent developed technology and advances. The material in standard books is so entrenched, old, and outdated material that one can be only amazed. For example, concept like potential stability is not discussed or even mentioned in any of all the books that this author review. This book written from physical point of view rather then construction point of view like all the books review by this author on stability. It is hoped that the book could be used as a reference book for people who have at least some basics knowledge of science areas such as algebra, basic physics, etc. Even without deep understating the graphs in this book can be used to find necessarily quantities needed to understand if to fix your vessel.