30 research outputs found
Hyperbolic Geometry: A Guide to Models and Motion
Get PDFTwentieth century mathematics can be characterized by the study of functions. The most interesting functions are those that preserve the structure at hand. In many branches of mathematics transformations are looked at and classified. In geometry, transformations of a plane are very important. A transformation that distance is called an isometry. The classification of isometries is known in Euclidean geometry, and one will learn about each of them in any geometry course. Classification of isometries for the hyperbolic plane are not as well known, but they have been classified. In this paper we will discover hyperbolic geometry, investigate some of the models used to view hyperbolic geometry and discuss some of the isometries of the hyperbolic plane
OPERATIONALIZING METAL ADDITIVE MANUFACTURING FOR EXPEDITIONARY EMPLOYMENT BY THE UNITED STATES MARINE CORPS
Get PDFThis thesis examines four metal additive manufacturing (AM) processes and assesses their suitability for ground expeditionary operations by the United States Marine Corps (USMC) through a cost effectiveness analysis. Metal AM, while in use in industrial applications for many years, has reached a maturity level where expeditionary employment is viable. However, a knowledge gap exists in understanding which technology is best suited for deployed operations. Concurrent with metal AM technology advancements, the USMC is conducting a significant reorganization and refocus on supporting distributed naval operations against peer threats, requiring new sustainment concepts. This thesis examines the cost effectiveness of each AM process to enable a reduced logistics footprint through production of parts as far forward and close to the point of need as possible, limiting supply stockpile size and minimizing transportation costs. Using AM process characteristics, printer cost data, and total quantity of parts produced over a five-year period, the cost-effectiveness (CE) ratio determined for each candidate process supports the recommendation of a hybrid AM process as the most cost-effective alternative.Lieutenant Colonel, United States Marine CorpsApproved for public release. Distribution is unlimited
Transistors
Get PDFContains reports on eight research projects.Lincoln Laboratory under Contract AF19(122)-45
The Components of the Science Collection
Get PDFPrevious papers have discussed the various aspects of
science literature for general reading so presumably all previous
steps already have been taken into consideration when the
basic ingredients of the collection- -or components, as the term
appears in the title of this paper are analyzed. This phrase,
somewhat anticlimatic, lands the author somewhere on the circumference
of a circle --perhaps that vicious one containing the
chicken and the egg. Or to put it another way, some may feel
that we had the "cart before the horse "--that, for example, one
does not select until he knows what to select for whom, why,
when, how, and where.
Much time could be wasted on the question of priorities
but, since this is the last discussion in the second series, we
cannot turn back and start all over again. Let us proceed,
therefore, to think about the composition of the collection, built
or re-built, in the light of what the reading public wants, where
to get it and how, as well as of other types of materials the general
reader might use to advantage once he becomes aware of
their existence. In this paper some suggestions may, of necessity,
emphasize those made by previous speakers; in fact, they
may be repetitive in spots. On the other hand there may be
some difference of opinion. By this time one gathers that the
general reader is a person of ordinary intelligence who has not
had recent training nor, up to now, specific knowledge of the
subject in which he has indicated an interest.published or submitted for publicatio
