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1. Clustering Honeybees by Its Daily Activity [Clustering Honeybees by Its Daily Activity]

   https://doi.org/10.5220/0007387505980604  

   Acuna, Edgar; Palomino, Velcy; Agosto, José; Mégret, Rémi; Giray, Tugrul; Prado, Alberto; Alaux, Cédric; Conte, Yves (February 2019, Proceedings of the 8th International Conference on Pattern Recognition Applications and Methods)

   In this work, we analyze the activity of bees starting at 6 days old. The data was collected at the INRA (France) during 2014 and 2016. The activity is counted according to whether the bees enter or leave the hive. After data wrangling, we decided to analyze data corresponding to a period of 10 days. We use clustering method to determine bees with similar activity and to estimate the time during the day when the bees are most active. To achieve our objective, the data was analyzed in three different time periods in a day. One considering the daily activity during in two periods: morning and afternoon, then looking at activities in periods of 3 hours from 8:00am to 8:00pm and, finally looking at the activities hourly from 8:00am to 8:00pm. Our study found two clusters of bees and in one of them clearly the bees activity increased at the day 5. The smaller cluster included the most active bees representing about 24 percent of the total bees under study. Also, the highest activity of the bees was registered between 2:00pm until 3:00pm. A Chi-square test shows that there is a combined effect Treatment× Colony on the clusters formation. 

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2. Microwave Microscopy and Its Applications

   https://doi.org/10.1146/annurev-matsci-081519-011844  

   Chu, Zhaodong; Zheng, Lu; Lai, Keji (July 2020, Annual Review of Materials Research)

   Understanding the nanoscale electrodynamic properties of a material at microwave frequencies is of great interest for materials science, condensed matter physics, device engineering, and biology. With specialized probes, sensitive detection electronics, and improved scanning platforms, microwave microscopy has become an important tool for cutting-edge materials research in the past decade. In this article, we review the basic components and data interpretation of microwave imaging and its broad range of applications. In addition to the general-purpose mapping of permittivity and conductivity, microwave microscopy is now exploited to perform quantitative measurements on semiconductor devices, photosensitive materials, ferroelectric domains and domain walls, and acoustic-wave systems. Implementation of the technique in low-temperature and high-magnetic-field chambers has also led to major discoveries in quantum materials with strong correlation and topological order. We conclude the review with an outlook of the ultimate resolution, operation frequency, and future industrial and academic applications of near-field microwave microscopy. Expected final online publication date for the Annual Review of Materials Research, Volume 50 is July 1, 2020. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates. 

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3. Stokes drift and its discontents

   https://doi.org/10.1098/rsta.2021.0032  

   Vanneste, Jacques; Young, William R. (June 2022, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences)

   The Stokes velocity u S , defined approximately by Stokes (1847, Trans. Camb. Philos. Soc. , 8 , 441–455.), and exactly via the Generalized Lagrangian Mean, is divergent even in an incompressible fluid. We show that the Stokes velocity can be naturally decomposed into a solenoidal component, u sol S , and a remainder that is small for waves with slowly varying amplitudes. We further show that u sol S arises as the sole Stokes velocity when the Lagrangian mean flow is suitably redefined to ensure its exact incompressibility. The construction is an application of Soward & Roberts’s glm theory (2010, J. Fluid Mech. , 661 , 45–72. ( doi:10.1017/S0022112010002867 )) which we specialize to surface gravity waves and implement effectively using a Lie series expansion. We further show that the corresponding Lagrangian-mean momentum equation is formally identical to the Craik–Leibovich (CL) equation with u sol S replacing u S , and we discuss the form of the Stokes pumping associated with both u S and u sol S . This article is part of the theme issue ‘Mathematical problems in physical fluid dynamics (part 1)’. 

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4. Exploratory Analysis and Its Malcontents

   https://doi.org/10.1162/99608f92.3b3cf5be  

   Heer, Jeffrey (July 2021, Harvard Data Science Review)

   null (Ed.)
5. Braided Zesting and Its Applications

   https://doi.org/10.1007/s00220-021-04002-4  

   Delaney, Colleen; Galindo, César; Plavnik, Julia; Rowell, Eric C.; Zhang, Qing (August 2021, Communications in Mathematical Physics)

   null (Ed.)