作者：
Bennett, GG[a1 ](C. N. Systems
Mosman New South Wales)About ten years ago this author wrote the software for a suite of navigation programmes which was resident in a small hand-held computer. In the course of this work it became apparent that the standard text books of navigation were perpetuating a flawed method of calculating rhumb lines on the Earth considered as an oblate spheroid. On further investigation it became apparent that these incorrect methods were being used in programming a number of calculator/computers and satellite navigation receivers. Although the discrepancies were not large it was disquieting to compare the results of the same rhumb line calculations from a number of such devices and find variations of some miles when the output was given and therefore purported to be accurate to a tenth of a mile in distance and/or a tenth of a minute of arc in position. The problem has been highlighted in the past and the references at the end of this show that a number of methods have been proposed for the amelioration of this problem. This paper summarizes formulae that the author recommends should be used for accurate solutions. Most of these may be found in standard geodetic text books such as but also provided are new formulae and schemes of solution which are suitable for use with computers or tables. The latter also take into account situations when a near-indeterminate solution may arise. Some examples are provided in an appendix which demonstrate the methods. The data for these problems do not refer to actual terrestrial situations but have been selected for illustrative purposes only. Practising ships' navigators will find the methods described in detail in this paper to be directly applicable to their work and also they should find ready acceptance because they are similar to current practice. In none of the references cited at the end of this paper has the practical task of calculating using either a computer or tabular techniques been addressed.
Blog This Article:Highlight allPractical Rhumb Line Calculations on the SpheroidG. G. Bennett (1996).Journal of Navigation, ">Volume 49, Issue01, January 1996 pp 112-119http://***/action/displayAbstract?aid=6...
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The code will display like thisPractical Rhumb Line Calculations on the Spheroid G. G. BennettJanuary 1996 Journal of Navigation,,Volume49, Issue01,January 1996 pp 112-119 http://***/abstract_S0373463300013151G. G. Bennett (1996). Practical Rhumb Line Calculations on the *** of Navigation,49, pp 112-119. doi:10.1017/S0373463300013151. Copyright StatementRights and PermissionsPrivacy PolicyTerms of UseFeedbackPress Releases? Cambridge University Press
Although precedences are often used to resolve ambiguities in programming language descriptions, there has been no parser-independent definition of languages which are generated by grammars with precedence rules. This...
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ISBN:
(纸本)3540600175
In this paper we show that the critical part of a correctness proof for implementations of higher-order functional languages is amenable to machine-assisted proof. An extended version of the lambda-calculus is considered, and the congruence between its direct and continuation semantics is proved. The proof has been constructed with the help of a generic theorem prover - Isabelle. The major part of the problem lies in establishing the existence of predicates which describe the congruence. This has been solved using Milne's inclusive predicate strategy [5]. The most important intermediate results and the main theorem as derived by Isabelle are quoted in the paper.
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作者：
FAIRHEAD, DLHALL, CCSince graduating from Cleveland State University in 1965 with a Bachelor of Science degree in Mathematics
he has worked for the Navy at Annapolis participating in several different automation efforts ranging from design aids to surface ship bridge control. Mr. Fairhead has completed graduate work in Computer Science at the University of Maryland has a certificate in Computer Programming holds a patent and is a member of the Association for Computing Machinery (ACM). Upon graduation from Morgan State in 1962
Mr. Hall was employed as a physicist at the Naval Surface Warfare Center Carderock Division Annapolis until 1994. During that time period he served as program technical manager for propulsion technology and as senior project scientist for several automation projects including the Automated Ships Bridge project. Mr. Hall also served as a member of the initial Technical Director's Technology Application Team and of the Autonomic Ship Innovation Center Team. Mr. Hall is a member of the American Institute of Physics and Sigma Pi Sigma (National Physics Honor Society).
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