Abstract Effective absorption of low-frequency waterborne sound with subwavelength absorbers has always been a challenging work.In this paper, dabcaps we derive two theoretical requirements for broadband perfect absorption of low-frequency waterborne sound by ultrathin acoustic metasurface under a finite-thickness steel plate followed by semi-infin
This study aimed to evaluate the acceptability of coronavirus disease of 2019 (COVID-19) vaccination among ophthalmology residents in Poland.An online, self-administered, anonymous survey was distributed among Polish ophthalmology residents in early 2021.Of 126 residents who completed the survey, 71.4% indicated that they would get vaccinated, 17.5
Customers often get attracted by lucrative deals and discounts offered by firms.These, attracted customers are termed as encouraged arrivals.In this paper, we developed a multi-server Feedback Markovian lt1 corvette engine covers queuing model with encouraged arrivals, customer impatience, and retention of impatient customers.The stationary system
Locating and analysing the location of new stores or outlets is one of the common issues facing retailers and franchisers.This is due to assure that new opening stores are at their strategic location to attract the highest possible number of customers.Spatial information is used to manage, maintain and analyse these store locations.However, since t