Motivated by multiplication algorithms based on redundant number representations, we study representations of an integer n as a sum n=∑kεkUk, where the digits εk are taken from a finite alphabet Σ and (Uk)k is a linear recurrent sequence of Pisot type with U0=1. The most prominent example of a base sequence (Uk)k is the sequence of Fibonacci numbers. We prove that the representations of minimal weight ∑k|εk| are recognised by a finite automaton and obtain an asymptotic formula for the average number of representations of minimal weight. Furthermore, we relate the maximal number of representations of a given integer to the joint spectral radius of a certain set of matrices.
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http://dx.doi.org/10.1016/j.tcs.2011.08.018 | DOI Listing |
J Anim Sci
January 2025
Faculdade de Medicina Veterinária e Zootecnia, Universidade Estadual Paulista, Botucatu, SP 18618-970, Brazil.
We evaluated the effects of breed and mineral source on heifer performance during periods of nutrient restriction and grazing. On day -7, ½ Angus × ½ Nelore (ANE) and Nelore (NE) heifers (12 heifers per breed; body weight, BW = 264 ± 35 kg; age = 15 ± 1 mo) were assigned to individual drylot pens to receive ad libitum Tifton 85 (Cynodon sp.) hay and white salt for 7 days.
View Article and Find Full Text PDFEnviron Health Perspect
January 2025
Department of Environmental Health, Boston University School of Public Health, Boston, Massachusetts, USA.
Background: Various countries have instituted risk governance measures to control and minimize the risks of chemicals at the national and international levels. Activities typically include risk assessment based on ) hazard and exposure assessments; ) setting limits on the production, use, and emissions of chemicals; ) enforcement of regulations; and ) monitoring the effectiveness of the measures taken. These steps largely depend on chemical analysis and access to pure chemical reference standards.
View Article and Find Full Text PDFActa Paediatr
January 2025
Department of Pediatric Cardiology, Queen Silvia Children's Hospital at the Sahlgrenska University Hospital, Gothenburg, Sweden.
Aim: Newborn infants with critical aortic arch obstruction are often undiagnosed at discharge, despite screening. This study investigated if adding the perfusion index improved early detection.
Methods: We retrospectively studied 38 newborn infants with critical aortic arch obstruction, who were routinely screened in 2014-2019 by 13 Swedish hospitals using pulse oximetry and the perfusion index.
The electron-bombarded active pixel sensor (EBAPS) is a highly sensitive vacuum-solid hybrid low-light imaging device capable of functioning in ultra-low illumination environments as low as 10-4 lx. However, this high sensitivity also causes problems, such as a low signal-to-noise ratio and complex noise. To enhance the quality of low-light night vision images captured by EBAPS and achieve effective imaging in ultra-low illumination, this study proposes a noise reduction algorithm based on the noise characteristics of EBAPS images.
View Article and Find Full Text PDFBiotechnol Biofuels Bioprod
January 2025
Institute for Pulsed Power and Microwave Technology (IHM), Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany.
Background: The gradual extrusion of water-soluble intracellular components (such as proteins) from microalgae after pulsed electric field (PEF) treatment is a well-documented phenomenon. This could be utilized in biorefinery applications with lipid extraction taking place after such an 'incubation' period, i.e.
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