New Models to Estimate Daytime and Shadow Length by Tracking the Shadow
DOI:
https://doi.org/10.61841/y8922q35Keywords:
Fitting Function, Shadow Length, Shadow Angle, Algorithm, Mathematical Model.Abstract
In this study, models are presented to estimate the time from an object's shadow angle and estimate the shadow length from daytime. A stick length of 10 cm was used to measure the shadow length and shadow angle from 7 am to 5 pm on the 1st, 11th, 12th, 13th, 21st, 22nd, and 30th of September 2019. A new algorithm is presented to extract the shadow length and angle automatically from the work images quickly and with high accuracy. The presented algorithm results for both shadow length and shadow angle show a good matching of the measured data. The introduced models' results, for daytime and shadow length, have good agreement with the real data. The highest value of normalized mean square error (NMSE), used as a criterion for daytime data (from the first model) and real daytime, was 0.029%. The NMSE for the real shadow length and shadow length (online) was 0.011%, while the value (NMSE) between the real shadow length and the resulting model was less than 0.010%. This small percentage shows a good match in the estimation of the daytime and shadow length of an outdoor object at different times of day. The presented models can generalize globally.
Downloads
Published
Issue
Section
License
Copyright (c) 2020 AUTHOR

This work is licensed under a Creative Commons Attribution 4.0 International License.
You are free to:
- Share — copy and redistribute the material in any medium or format for any purpose, even commercially.
- Adapt — remix, transform, and build upon the material for any purpose, even commercially.
- The licensor cannot revoke these freedoms as long as you follow the license terms.
Under the following terms:
- Attribution — You must give appropriate credit , provide a link to the license, and indicate if changes were made . You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
- No additional restrictions — You may not apply legal terms or technological measures that legally restrict others from doing anything the license permits.
Notices:
You do not have to comply with the license for elements of the material in the public domain or where your use is permitted by an applicable exception or limitation .
No warranties are given. The license may not give you all of the permissions necessary for your intended use. For example, other rights such as publicity, privacy, or moral rights may limit how you use the material.