A fast, simple, and stable Chebyshev-Legendre transform using an asymptotic formula

A fast, simple, and numerically stable transform for converting between Legendre and Chebyshev coefficients of a degree $N$ polynomial in $O(N(\log N)^{2}/ \log \log N)$ operations is derived. The basis of the algorithm is to rewrite a well-known asymptotic formula for Legendre polynomials of large degree as a weighted linear combination of Chebyshev polynomials, which can then be evaluated by using the discrete cosine transform. Numerical results are provided to demonstrate the efficiency and numerical stability. Since the algorithm evaluates a Legendre expansion at an $N+1$ Chebyshev grid as an intermediate step, it also provides a fast transform between Legendre coefficients and values on a Chebyshev grid

Trifort: A Toy Prototype

Repeated triangular modules provide the user direct interaction with physical forces, gaining insight into a world governed by geometry

Exploring site formation and building local contexts through wiggle-match radiocarbon dating: re-dating of the Firth of Clyde Crannogs, Scotland

There are at least four wooden intertidal platforms, also known as marine crannogs, in the Firth of Clyde, on the west coast of Scotland. The interpretation of these sites partly depends on their dating and, if coeval, they could point to the presence of a native maritime hub. Furthermore, the spatial coincidence with the terminus of the Antonine Wall has led to speculation about the role they may have played in Roman-native interaction during the occupation of southern Scotland in the early first millennium cal ad. Hence, a better absolute chronology is essential to evaluate whether the marine crannogs were contemporary with one another and whether they related to any known historic events. This article presents results of a wiggle-match dating project aimed at resolving these uncertainties at two of the sites in question, Dumbuck and Erskine Bridge crannogs. The results show that the construction of these sites pre-date direct Roman influence in Scotland. Furthermore, the results indicate that the two sites were built at least 300 years apart, forcing us to consider the possibility that they may have functioned in very different historical contexts. Other findings include technical observations on the fine shape of the radiocarbon calibration curve near the turn of the first millennia bc/ad and potential evidence for persistent contamination in decayed and exposed sections of waterlogged alder

Starter House for an ARchitect

The Starter House is a 1000 sq. ft. home situated on a wooded site in Ames, Iowa. Students designed these homes imagining themselves as a recently-graduated client, emphasizing spatial efficiency and the act of dwelling - particularly in a natural environment. This project served as a springboard into a more developed design with passive solar considerations

App-licable Techology

Autism Spectrum Disorder (ASD) has seen an increase in prevalence in the United States presenting in 1 in 59 children. ASD presents with an array of symptoms that impact various aspects of life including but not limited to, social interaction, attention, and behavioral modulation (Voss et al., 2019). Meristem is a transitional program for individuals ages 18-28 that prepares young adults on the transition of adulthood while coping with the various symptoms of ASD. At our fieldwork site, our collective mission has been to focus on sensory and mood self-regulation to improve the individual\u27s independence during situations. Technology can play a vital role in helping achieve this goal through the utilization of personal device applications

Radiocarbon wiggle-match dating in the intertidal zone

Radiocarbon wiggle-match dating is a technique that can combine the versatility of radiocarbon dating with chronological information from tree-rings. This makes it useful in contexts where timbers are preserved, but dendrochronological dating is impossible. As intertidal and marine timbers are waterlogged, this can favor their preservation and hence allow wiggle-match 14C dating, which can be of significant help in deriving relatively precise chronologies for a range of coastal structures. As the technique depends on making multiple radiocarbon measurements towards a single date, efficiency in application is the key and hence a number of practical considerations need to be taken into account in advance of conducting a dating program. This paper discusses some of these practical concerns and reviews them in the context of the intertidal crannogs in the Firth of Clyde on the west coast of Scotland

3D heritage visualisation and the negotiation of authenticity: the ACCORD project

This article examines the question of authenticity in relation to 3D visualisation of historic objects and monuments. Much of the literature locates their authenticity in the accuracy of the data and/or the realism of the resulting models. Yet critics argue that 3D visualisations undermine the experience of authenticity, disrupting people’s access to the materiality, biography and aura of their historic counterparts. The ACCORD project takes questions of authenticity and 3D visualisation into a new arena – that of community heritage practice – and uses rapid ethnographic methods to examine whether and how such visualisations acquire authenticity. The results demonstrate that subtle forms of migration and borrowing occur between the original and the digital, creating new forms of authenticity associated with the digital object. Likewise, the creation of digital models mediates the authenticity and status of their original counterparts through the networks of relations in which they are embedded. The current pre-occupation with the binary question of whether 3D digital models are authentic or not obscures the wider work that such objects do in respect to the cultural politics of ownership, attachment, place-making and regeneration. The article both advances theoretical debates and has important implications for heritage visualisation practice