Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Reconstruction of vertical and L-shaped ancient Egyptian sundials and
  methods for measuring time   The article presents the results of the study of design features of vertical
and L-shaped ancient Egyptian sundials. With the help of astronomical methods
were developed their models, based on which the reconstruction of a sundial was
held. Also, the original scheme is a simple way to fairly precise of
measurement of time with them has been developed. Large urgency of the task due
to the lack of similar models and schemes to date. Model offered by us, which
describes the vertical sundial, is a vertical sundial, with a sloping gnomon,
which takes into account latitude of area. It is based on the assumption of the
existence in ancient Egypt representations about an hour (and a half hour) of
equal duration throughout the day, does not depend on the time of year. Offered
by us model is characterized by marking hour lines from 6 to 12 hours after
each hour. From 12 to 12.5 hours produced displacement in the markup of hour
lines on half an hour, then the markup is repeated every hour. As a
consequence, the reconstruction of the vertical sundials, we have developed and
proposed a model that describes the design features and operation of the
L-shaped sundials of two types. They had to work together with the inclined
gnomon, like vertical sundials or directly with vertical sundials. In this
case, L-shaped sundials can complement vertical sundials, providing an
opportunity to read the caption to hour markers and interpret the indications
of vertical sundials because vertical sundials inscription missing. The article
also describes explanation of the inscriptions from the tomb of Seti I, long
intriguing researchers. It is proved that the inscription contains the length
of the intervals between adjacent markers L-shaped sundial of the second type,
where the first interval corresponds to a half of hour. Keywords: sundial,
model, astronomical methods, archaeoastronomy, ancient Egypt.

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The categories of this paper are: econ
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The categories of this paper are: atom-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: gr-qc
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The categories of this paper are: eess
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The categories of this paper are: hep-lat
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The categories of this paper are: comp-gas
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The categories of this paper are: nlin
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The categories of this paper are: hep-ex
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The categories of this paper are: plasm-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: chem-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: hep-th
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The categories of this paper are: dg-ga